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Dong F, Hao L, Wang L, Huang Y. Clickable nanozyme enhances precise colonization of probiotics for ameliorating inflammatory bowel disease. J Control Release 2024; 373:749-765. [PMID: 39084465 DOI: 10.1016/j.jconrel.2024.07.064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2024] [Revised: 07/25/2024] [Accepted: 07/26/2024] [Indexed: 08/02/2024]
Abstract
Convincing evidence suggests that aberrant gut microbiota changes play a critical role in the progression and pathogenesis of inflammatory bowel disease (IBD). Probiotic therapeutic interventions targeting the microbiota may provide alternative avenues to treat IBD, but currently available probiotics often suffer from low intestinal colonization and limited targeting capability. Here, we developed azido (N3)-modified Prussian blue nanozyme (PB@N3) spatio-temporal guidance enhances the targeted colonization of probiotics to alleviate intestinal inflammation. First, clickable PB@N3 targets intestinal inflammation, simultaneously, it scavenges reactive oxygen species (ROS). Subsequently, utilizing "click" chemistry to spatio-temporally guide targeted colonization of dibenzocyclooctyne (DBCO)-modified Lactobacillus reuteri DSM 17938 (LR@DBCO). The "click" reaction between PB@N3 and LR@DBCO has excellent specificity and efficacy both in vivo and in vitro. Despite the complex physiological environment of IBD, "click" reaction can prolong the retention time of probiotics in the intestine. Dextran sulfate sodium (DSS)-induced colitis mice model, demonstrates that the combination of PB@N3 and LR@DBCO effectively mitigates levels of ROS, enhances the colonization of probiotics, modulates intestinal flora composition and function, regulates immune profiles, restores intestinal barrier function, and alleviates intestinal inflammation. Hence, PB@N3 spatio-temporal guidance enhances targeted colonization of LR@DBCO provides a promising medical treatment strategy for IBD.
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Affiliation(s)
- Fang Dong
- Department of Gastroenterology, Pediatric Inflammatory Bowel Disease Research Center, National Children's Medical Center, Children's Hospital of Fudan University, Shanghai 201102, China
| | - Liangwen Hao
- The Institute for Biomedical Engineering and Nano Science School of Medicine, Tongji University, Shanghai 200072, China
| | - Lin Wang
- Department of Gastroenterology, Pediatric Inflammatory Bowel Disease Research Center, National Children's Medical Center, Children's Hospital of Fudan University, Shanghai 201102, China
| | - Ying Huang
- Department of Gastroenterology, Pediatric Inflammatory Bowel Disease Research Center, National Children's Medical Center, Children's Hospital of Fudan University, Shanghai 201102, China.
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2
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Li Q, Zhang C, Zhu M, Shan J, Qian H, Ma Y, Wang X. W-GA nanodots restore intestinal barrier functions by regulating flora disturbance and relieving excessive oxidative stress to alleviate colitis. Acta Biomater 2024; 182:260-274. [PMID: 38777175 DOI: 10.1016/j.actbio.2024.05.030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2024] [Revised: 05/10/2024] [Accepted: 05/15/2024] [Indexed: 05/25/2024]
Abstract
Inflammatory bowel disease (IBD) may arise due to disruption of mucosal barriers as a result of dysregulation of the intestinal flora and excessive oxidative stress. The creation of nanomaterials with only microbiota-regulating effects often leads to inadequate therapeutic outcomes caused by the disruption of a healthy microbial balance and the emergence of tissue harm caused by excessive oxidative stress. This report describes the multifunctional activity of ultrasmall W-GA nanodots, which can precisely regulate the intestinal microbiome by inhibiting the abnormal expansion of Enterobacteriaceae during colitis and alleviating the damage caused by oxidative stress to the reconstructive microflora, ultimately restoring intestinal barrier function. W-GA nanodots have been synthesized through a simple coordination reaction and can be dispersed in various solvents in vitro, demonstrating favorable safety profiles in cells, significant clearance of reactive oxygen and nitrogen species (RONS), and increased cell survival in models of oxidative stress induced by hydrogen peroxide (H2O2). Through oral or intravenous administration, the W-GA nanodots were shown to be highly safe when tested in vivo, and they effectively reduced colon damage in mice with DSS-induced colitis by restoring the integrity of the intestinal barrier. W-GA nanodots have enabled the integration of microflora reprogramming and RONS clearance, creating a potent therapeutic strategy for treating gut inflammation. Consequently, the development of W-GA nanodots represents a promising strategy for enhancing the formation and preservation of the intestinal barrier to treat IBD by suppressing the growth of Enterobacteriaceae, a type of facultative anaerobic bacterium, and facilitating the effective removal of RONS. Ultimately, this leads to the restoration of the intestinal barrier's functionality. STATEMENT OF SIGNIFICANCE: An increasing number of nanoparticles are under development for treating inflammatory bowel disease. Although they can alleviate inflammation symptoms by regulating reactive oxygen and nitrogen species (RONS) and microbiota, their understanding of the mechanism behind microbiota regulation is limited. This study synthesized W-GA nanodots using a straightforward one-pot synthesis method. Simple synthesis holds significant promise for clinical applications, as it encompasses multiple nanoenzyme functions and also exhibits Enterobacteriaceae inhibitory properties.Thus, it contributes to ameliorating the current medical landscape of inflammatory bowel disease.
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Affiliation(s)
- Qingrong Li
- Department of Pharmacology, School of Basic Medical Sciences, Anhui Medical University, Hefei 230032, PR China; School of Biomedical Engineering, Research and Engineering Center of Biomedical Materials, Anhui Provincial Institute of Translational Medicine, Anhui Medical University, Hefei 230032, PR China
| | - Cong Zhang
- Division of Gastroenterology, The First Affiliated Hospital of USTC, Division of Life Science and Medicine, University of Science and Technology of China, Hefei, Anhui 230026, PR China
| | - Mengmei Zhu
- Department of Pharmacology, School of Basic Medical Sciences, Anhui Medical University, Hefei 230032, PR China
| | - Jie Shan
- Department of Burns, The First Affiliated Hospital of Anhui Medical University, Hefei 230032, PR China
| | - Haisheng Qian
- Department of Pharmacology, School of Basic Medical Sciences, Anhui Medical University, Hefei 230032, PR China; School of Biomedical Engineering, Research and Engineering Center of Biomedical Materials, Anhui Provincial Institute of Translational Medicine, Anhui Medical University, Hefei 230032, PR China.
| | - Yan Ma
- School of Biomedical Engineering, Research and Engineering Center of Biomedical Materials, Anhui Provincial Institute of Translational Medicine, Anhui Medical University, Hefei 230032, PR China.
| | - Xianwen Wang
- School of Biomedical Engineering, Research and Engineering Center of Biomedical Materials, Anhui Provincial Institute of Translational Medicine, Anhui Medical University, Hefei 230032, PR China.
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3
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Lardenoije CMJG, van Riel SJJM, Peters LJF, Wassen MMLH, Cremers NAJ. Medical-Grade Honey as a Potential New Therapy for Bacterial Vaginosis. Antibiotics (Basel) 2024; 13:368. [PMID: 38667044 PMCID: PMC11047503 DOI: 10.3390/antibiotics13040368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Revised: 04/12/2024] [Accepted: 04/14/2024] [Indexed: 04/29/2024] Open
Abstract
The prevalence of bacterial vaginosis (BV) among women of reproductive age is 29%. BV arises from a vaginal imbalance marked by reduced levels of lactic acid-producing lactobacilli and an overgrowth of pathogenic anaerobes. The multifactorial nature of BV's pathogenesis complicates its treatment. Current antibiotic therapy exhibits a recurrence rate of about 60% within a year. Recurrence can be caused by antibiotic treatment failure (e.g., due to antimicrobial resistance), the persistence of residual infections (e.g., due to biofilm formation), and re-infection. Because of the high recurrence rates, alternative therapies are required. Medical-grade honey (MGH), known for its antimicrobial and wound healing properties in wound care, emerges as a potential novel therapy for BV. MGH exerts broad-spectrum antimicrobial activity, employing multiple mechanisms to eliminate the risk of resistance. For example, the low pH of MGH and the production of hydrogen peroxide benefit the microbiota and helps restore the natural vaginal balance. This is supported by in vitro studies demonstrating that MGH has an antibacterial effect on several pathogenic bacteria involved in the pathophysiology of BV, while lactobacilli and the vaginal microenvironment can be positively affected. In contrast to antibiotics, MGH exerts anti-biofilm activity, affects the microbiome as pre- and probiotic, and modulates the vaginal microenvironment through its anti-inflammatory, anti-oxidative, physicochemical, and immunomodulatory properties. More clinical research is required to confirm the positive effect of MGH on BV and to investigate the long-term cure rate.
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Affiliation(s)
- Céline M. J. G. Lardenoije
- Department of Gynecology and Obstetrics, Maastricht University Medical Centre+, P. Debyelaan 25, 6229 HX Maastricht, The Netherlands; (C.M.J.G.L.); (S.J.J.M.v.R.)
| | - Senna J. J. M. van Riel
- Department of Gynecology and Obstetrics, Maastricht University Medical Centre+, P. Debyelaan 25, 6229 HX Maastricht, The Netherlands; (C.M.J.G.L.); (S.J.J.M.v.R.)
- Department of Obstetrics & Gynecology, Zuyderland Medical Centre Heerlen, Henri Dunantstraat 5, 6419 PC Heerlen, The Netherlands;
- VieCuri Medical Centre, Tegelseweg 210, 5912 BL Venlo, The Netherlands
- GROW Research Institute for Oncology and Reproduction, Universiteitssingel 40, 6229 ER Maastricht, The Netherlands
| | | | - Martine M. L. H. Wassen
- Department of Obstetrics & Gynecology, Zuyderland Medical Centre Heerlen, Henri Dunantstraat 5, 6419 PC Heerlen, The Netherlands;
| | - Niels A. J. Cremers
- Department of Gynecology and Obstetrics, Maastricht University Medical Centre+, P. Debyelaan 25, 6229 HX Maastricht, The Netherlands; (C.M.J.G.L.); (S.J.J.M.v.R.)
- Triticum Exploitatie BV, Sleperweg 44, 6222 NK Maastricht, The Netherlands;
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Gong X, Geng H, Yang Y, Zhang S, He Z, Fan Y, Yin F, Zhang Z, Chen GQ. Metabolic engineering of commensal bacteria for gut butyrate delivery and dissection of host-microbe interaction. Metab Eng 2023; 80:94-106. [PMID: 37717646 DOI: 10.1016/j.ymben.2023.09.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 09/14/2023] [Accepted: 09/14/2023] [Indexed: 09/19/2023]
Abstract
An overwhelming number of studies have reported the correlation of decreased abundance of butyrate-producing commensals with a wide range of diseases. However, the molecular-level mechanisms whereby gut butyrate causally affects the host mucosal immunity and pathogenesis were poorly understood, hindered by the lack of efficient tools to control intestinal butyrate. Here we engineered a facultative anaerobic commensal bacterium to delivery butyrate at the intestinal mucosal surface, and implemented it to dissect the causal role of gut butyrate in regulating host intestinal homeostasis in a model of murine chronic colitis. Mechanistically, we show that gut butyrate protected against colitis and preserved intestinal mucosal homeostasis through its inhibiting effect on the key pyroptosis executioner gasdermin D (GSDMD) of colonic epithelium, via functioning as an HDAC3 inhibitor. Overall, our work presents a new avenue to build synthetic living delivery bacteria to decode causal molecules at the host-microbe interface with molecular-level insights.
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Affiliation(s)
- Xu Gong
- Beijing Advanced Innovation Centre for Biomedical Engineering, Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Engineering Medicine, Beihang University, Beijing, 100191, PR China; Key Laboratory of Big Data-Based Precision Medicine, Ministry of Industry and Information Technology, Beihang University, Beijing, 100191, PR China
| | - Hongwei Geng
- Beijing Advanced Innovation Centre for Biomedical Engineering, Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Engineering Medicine, Beihang University, Beijing, 100191, PR China; Key Laboratory of Big Data-Based Precision Medicine, Ministry of Industry and Information Technology, Beihang University, Beijing, 100191, PR China
| | - Yun Yang
- Beijing Advanced Innovation Centre for Biomedical Engineering, Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Engineering Medicine, Beihang University, Beijing, 100191, PR China; Key Laboratory of Big Data-Based Precision Medicine, Ministry of Industry and Information Technology, Beihang University, Beijing, 100191, PR China.
| | - Shuyi Zhang
- School of Pharmaceutical Sciences, Tsinghua University, Beijing, 100084, PR China; Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, PR China
| | - Zilong He
- Beijing Advanced Innovation Centre for Biomedical Engineering, Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Engineering Medicine, Beihang University, Beijing, 100191, PR China
| | - Yubo Fan
- Beijing Advanced Innovation Centre for Biomedical Engineering, Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Engineering Medicine, Beihang University, Beijing, 100191, PR China
| | - Fengyi Yin
- Beijing Advanced Innovation Centre for Biomedical Engineering, Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Engineering Medicine, Beihang University, Beijing, 100191, PR China
| | - Zhifa Zhang
- Beijing Advanced Innovation Centre for Biomedical Engineering, Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Engineering Medicine, Beihang University, Beijing, 100191, PR China
| | - Guo-Qiang Chen
- Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, PR China; MOE Key Lab of Industrial Biocatalysis, Department of Chemical Engineering, Tsinghua University, Beijing, 100084, PR China; Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, 100084, PR China.
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5
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Donkor GY, Anderson GM, Stadler M, Tawiah PO, Orellano CD, Edwards KA, Dahl JU. A novel ruthenium-silver based antimicrobial potentiates aminoglycoside activity against Pseudomonas aeruginosa. mSphere 2023; 8:e0019023. [PMID: 37646510 PMCID: PMC10597350 DOI: 10.1128/msphere.00190-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Accepted: 07/05/2023] [Indexed: 09/01/2023] Open
Abstract
The rapid dissemination of antibiotic resistance combined with the decline in the discovery of novel antibiotics represents a major challenge for infectious disease control that can only be mitigated by investments in novel treatment strategies. Alternative antimicrobials, including silver, have regained interest due to their diverse mechanisms of inhibiting microbial growth. One such example is AGXX, a broad-spectrum antimicrobial that produces highly cytotoxic reactive oxygen species (ROS) to inflict extensive macromolecular damage. Due to the connections identified between ROS production and antibiotic lethality, we hypothesized that AGXX could potentially increase the activity of conventional antibiotics. Using the gram-negative pathogen Pseudomonas aeruginosa, we screened possible synergistic effects of AGXX on several antibiotic classes. We found that the combination of AGXX and aminoglycosides tested at sublethal concentrations led to a rapid exponential decrease in bacterial survival and restored the sensitivity of a kanamycin-resistant strain. ROS production contributes significantly to the bactericidal effects of AGXX/aminoglycoside treatments, which is dependent on oxygen availability and can be reduced by the addition of ROS scavengers. Additionally, P. aeruginosa strains deficient in ROS detoxifying/repair genes were more susceptible to AGXX/aminoglycoside treatment. We further demonstrate that this synergistic interaction was associated with a significant increase in outer and inner membrane permeability, resulting in increased antibiotic influx. Our study also revealed that AGXX/aminoglycoside-mediated killing requires an active proton motive force across the bacterial membrane. Overall, our findings provide an understanding of cellular targets that could be inhibited to increase the activity of conventional antimicrobials. IMPORTANCE The emergence of drug-resistant bacteria coupled with the decline in antibiotic development highlights the need for novel alternatives. Thus, new strategies aimed at repurposing conventional antibiotics have gained significant interest. The necessity of these interventions is evident especially in gram-negative pathogens as they are particularly difficult to treat due to their outer membrane. This study highlights the effectiveness of the antimicrobial AGXX in potentiating aminoglycoside activities against P. aeruginosa. The combination of AGXX and aminoglycosides not only reduces bacterial survival rapidly but also significantly re-sensitizes aminoglycoside-resistant P. aeruginosa strains. In combination with gentamicin, AGXX induces increased endogenous oxidative stress, membrane damage, and iron-sulfur cluster disruption. These findings emphasize AGXX's potential as a route of antibiotic adjuvant development and shed light on potential targets to enhance aminoglycoside activity.
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Affiliation(s)
- Gracious Yoofi Donkor
- School of Biological Sciences, Illinois State University, Microbiology, Normal, Illinois, USA
| | - Greg M. Anderson
- School of Biological Sciences, Illinois State University, Microbiology, Normal, Illinois, USA
| | - Michael Stadler
- School of Biological Sciences, Illinois State University, Microbiology, Normal, Illinois, USA
| | - Patrick Ofori Tawiah
- School of Biological Sciences, Illinois State University, Microbiology, Normal, Illinois, USA
| | - Carl D. Orellano
- School of Biological Sciences, Illinois State University, Microbiology, Normal, Illinois, USA
| | - Kevin A. Edwards
- School of Biological Sciences, Illinois State University, Cell Biology, Normal, Illinois, USA
| | - Jan-Ulrik Dahl
- School of Biological Sciences, Illinois State University, Microbiology, Normal, Illinois, USA
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6
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Donkor GY, Anderson GM, Stadler M, Tawiah PO, Orellano CD, Edwards KA, Dahl JU. The Novel Silver-Containing Antimicrobial Potentiates Aminoglycoside Activity Against Pseudomonas aeruginosa. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.15.532855. [PMID: 36993297 PMCID: PMC10055142 DOI: 10.1101/2023.03.15.532855] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The rapid dissemination of antibiotic resistance combined with the decline in the discovery of novel antibiotics represents a major challenge for infectious disease control that can only be mitigated by investments into novel treatment strategies. Alternative antimicrobials, including silver, have regained interest due to their diverse mechanisms of inhibiting microbial growth. One such example is AGXX®, a broad-spectrum silver containing antimicrobial that produces highly cytotoxic reactive oxygen species (ROS) to inflict extensive macromolecular damage. Due to connections identified between ROS production and antibiotic lethality, we hypothesized that AGXX® could potentially increase the activity of conventional antibiotics. Using the gram-negative pathogen Pseudomonas aeruginosa, we screened possible synergistic effects of AGXX® on several antibiotic classes. We found that the combination of AGXX® and aminoglycosides tested at sublethal concentrations led to a rapid exponential decrease in bacterial survival and restored sensitivity of a kanamycin-resistant strain. ROS production contributes significantly to the bactericidal effects of AGXX®/aminoglycoside treatments, which is dependent on oxygen availability and can be reduced by the addition of ROS scavengers. Additionally, P. aeruginosa strains deficient in ROS detoxifying/repair genes were more susceptible to AGXX®/aminoglycoside treatment. We further demonstrate that this synergistic interaction was associated with significant increase in outer and inner membrane permeability, resulting in increased antibiotic influx. Our study also revealed that AGXX®/aminoglycoside-mediated killing requires an active proton motive force across the bacterial membrane. Overall, our findings provide an understanding of cellular targets that could be inhibited to increase the activity of conventional antimicrobials.
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7
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Cao F, Jin L, Gao Y, Ding Y, Wen H, Qian Z, Zhang C, Hong L, Yang H, Zhang J, Tong Z, Wang W, Chen X, Mao Z. Artificial-enzymes-armed Bifidobacterium longum probiotics for alleviating intestinal inflammation and microbiota dysbiosis. NATURE NANOTECHNOLOGY 2023; 18:617-627. [PMID: 36973397 DOI: 10.1038/s41565-023-01346-x] [Citation(s) in RCA: 74] [Impact Index Per Article: 74.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Accepted: 02/03/2023] [Indexed: 06/18/2023]
Abstract
Inflammatory bowel disease can be caused by the dysfunction of the intestinal mucosal barrier and dysregulation of gut microbiota. Traditional treatments use drugs to manage inflammation with possible probiotic therapy as an adjuvant. However, current standard practices often suffer from metabolic instability, limited targeting and result in unsatisfactory therapeutic outcomes. Here we report on artificial-enzyme-modified Bifidobacterium longum probiotics for reshaping a healthy immune system in inflammatory bowel disease. Probiotics can promote the targeting and retention of the biocompatible artificial enzymes to persistently scavenge elevated reactive oxygen species and alleviate inflammatory factors. The reduced inflammation caused by artificial enzymes improves bacterial viability to rapidly reshape the intestinal barrier functions and restore the gut microbiota. The therapeutic effects are demonstrated in murine and canine models and show superior outcomes to traditional clinical drugs.
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Affiliation(s)
- Fangfang Cao
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, China
- Departments of Diagnostic Radiology, Surgery, Chemical and Biomolecular Engineering, and Biomedical Engineering, Yong Loo Lin School of Medicine and College of Design and Engineering, National University of Singapore, Singapore, Singapore
- Nanomedicine Translational Research Program, NUS Center for Nanomedicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Lulu Jin
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, China
| | - Yong Gao
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, China
| | - Yuan Ding
- Department of Hepatobiliary and Pancreatic Surgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Hongyang Wen
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, China
- Department of Hepatobiliary and Pancreatic Surgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Zhefeng Qian
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, China
- Department of Hepatobiliary and Pancreatic Surgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Chenyin Zhang
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, China
| | - Liangjie Hong
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, China
| | - Huang Yang
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, China
| | - Jiaojiao Zhang
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, China
| | - Zongrui Tong
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, China
- Department of Hepatobiliary and Pancreatic Surgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Weilin Wang
- Department of Hepatobiliary and Pancreatic Surgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China.
| | - Xiaoyuan Chen
- Departments of Diagnostic Radiology, Surgery, Chemical and Biomolecular Engineering, and Biomedical Engineering, Yong Loo Lin School of Medicine and College of Design and Engineering, National University of Singapore, Singapore, Singapore.
- Nanomedicine Translational Research Program, NUS Center for Nanomedicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
- Clinical Imaging Research Centre, Centre for Translational Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore.
| | - Zhengwei Mao
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, China.
- Department of Hepatobiliary and Pancreatic Surgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China.
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Lei H, Jin C, Xiao Z, Chen J, Leghari SJ, Pan H. Relationship between pepper (Capsicum annuum L.) root morphology, inter-root soil bacterial community structure and diversity under water-air intercropping conditions. PLANTA 2023; 257:98. [PMID: 37067628 DOI: 10.1007/s00425-023-04134-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Accepted: 04/10/2023] [Indexed: 06/19/2023]
Abstract
The combination of water and gas at an aeration rate of 15 mg/L and irrigation amount of 0.8 Ep significantly promoted the root morphology, inter-root soil bacterial community structure and diversity of pepper, enhanced the structure of molecular symbiotic network, and stimulated the potential ecosystem function. Poor aeration adversely affects the root morphology of pepper (Capsicum annuum L.) and bacterial community. It is critical to understand the effects of water-air interactions on root morphology and bacterial community structure and diversity. A randomized block experiment was conducted under the two aeration rates of dissolved oxygen mass concentrations, including A: 15 mg/L, O: 40 mg/L, and C: non-aeration as control treatment, and two irrigation rates of W1 and W2 (0.8 Ep and 1.0 Ep). The results showed that aerated irrigation had a significant effect on the root morphology of pepper. Compared with treatment CW1, treatment AW1 increased root dry weight, root length, root volume, and root surface area by 13.63%, 11.09%, 59.47%, and 61.67%, respectively (P < 0.05). Aerated irrigation significantly increased the relative abundance of Actinobacteria, Gemmatimonadetes, Alphaproteobacteria, Gemmatimonas, Sphingomonas, and KD4-96 aerobic beneficial bacteria. It decreased the relative abundance of Proteobacteria, Monomycetes, Bacteroidetes, Corynebacterium, Gammaproteobacteria, Anaerolineae, Subgroup_6, MND1, Haliangium, and Thiobacillus. The Pielou_e, Shannon and Simpson indexes of treatment AW1 were significantly higher than treatments OW1 and CW1. The results of the β-diversity of bacterial communities showed that the structure of soil bacterial communities differed significantly among treatments. Actinobacteria was a key phylum affecting root morphology, and AW1 treatment was highly correlated with Actinobacteria. Molecular ecological network analysis showed a relatively high number of bacterial network nodes and more complex relationships among species under the aeration of level 15 mg/L and 0.8 Ep, as well as the emergence of new phylum-level beneficial species: Dependentiae, BRC1, Cyanobacteria, Deinococcus-Thermus, Firmicutes, and Planctomycetes. Therefore, the aeration of 15 mg/L and 0.8 times crop-evaporation coefficient can increase root morphology, inter-root soil bacterial community diversity and bacterial network structure, and enhance potential ecosystem functions in the rhizosphere.
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Affiliation(s)
- Hongjun Lei
- School of Water Conservancy, North China University of Water Resources and Electric Power, Zhengzhou, 450046, China
| | - Cuicui Jin
- School of Water Conservancy, North China University of Water Resources and Electric Power, Zhengzhou, 450046, China
| | - Zheyuan Xiao
- School of Water Conservancy, North China University of Water Resources and Electric Power, Zhengzhou, 450046, China
| | - Jian Chen
- School of Water Conservancy, North China University of Water Resources and Electric Power, Zhengzhou, 450046, China
| | - Shah Jahan Leghari
- College of Land Science and Technology, China Agricultural University, Beijing, 100193, China
| | - Hongwei Pan
- School of Water Conservancy, North China University of Water Resources and Electric Power, Zhengzhou, 450046, China.
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9
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Pan J, Zhou J, Tang X, Guo Y, Zhao Y, Liu S. Bacterial Communication Coordinated Behaviors of Whole Communities to Cope with Environmental Changes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:4253-4265. [PMID: 36862939 DOI: 10.1021/acs.est.2c05780] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Bacterial communication plays an important role in coordinating microbial behaviors in a community. However, how bacterial communication organizes the entire community for anaerobes to cope with varied anaerobic-aerobic conditions remains unclear. We constructed a local bacterial communication gene (BCG) database comprising 19 BCG subtypes and 20279 protein sequences. BCGs in anammox-partial nitrification consortia coping with intermittent aerobic and anaerobic conditions as well as gene expressions of 19 species were inspected. We found that when suffering oxygen changes, intra- and interspecific communication by a diffusible signal factor (DSF) and bis-(3'-5')-cyclic dimeric guanosine monophosphate (c-di-GMP) changed first, which in turn induced changes of autoinducer-2 (AI-2)-based interspecific and acyl homoserine lactone (AHLs)-based intraspecific communication. DSF and c-di-GMP-based communication regulated 455 genes, which covered 13.64% of the genomes and were mainly involved in antioxidation and metabolite residue degradation. For anammox bacteria, oxygen influenced DSF and c-di-GMP-based communication through RpfR to upregulate antioxidant proteins, oxidative damage-repairing proteins, peptidases, and carbohydrate-active enzymes, which benefited their adaptation to oxygen changes. Meanwhile, other bacteria also enhanced DSF and c-di-GMP-based communication by synthesizing DSF, which helped anammox bacteria survive at aerobic conditions. This study evidences the role of bacterial communication as an "organizer" within consortia to cope with environmental changes and sheds light on understanding bacterial behaviors from the perspective of sociomicrobiology.
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Affiliation(s)
- Juejun Pan
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
| | - Jianhang Zhou
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
| | - Xi Tang
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
| | - Yongzhao Guo
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
| | - Yunpeng Zhao
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
| | - Sitong Liu
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
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10
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van Erk MR, Bourceau OM, Moncada C, Basu S, Hansel CM, de Beer D. Reactive oxygen species affect the potential for mineralization processes in permeable intertidal flats. Nat Commun 2023; 14:938. [PMID: 36804536 PMCID: PMC9941506 DOI: 10.1038/s41467-023-35818-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 01/03/2023] [Indexed: 02/22/2023] Open
Abstract
Intertidal permeable sediments are crucial sites of organic matter remineralization. These sediments likely have a large capacity to produce reactive oxygen species (ROS) because of shifting oxic-anoxic interfaces and intense iron-sulfur cycling. Here, we show that high concentrations of the ROS hydrogen peroxide are present in intertidal sediments using microsensors, and chemiluminescent analysis on extracted porewater. We furthermore investigate the effect of ROS on potential rates of microbial degradation processes in intertidal surface sediments after transient oxygenation, using slurries that transitioned from oxic to anoxic conditions. Enzymatic removal of ROS strongly increases rates of aerobic respiration, sulfate reduction and hydrogen accumulation. We conclude that ROS are formed in sediments, and subsequently moderate microbial mineralization process rates. Although sulfate reduction is completely inhibited in the oxic period, it resumes immediately upon anoxia. This study demonstrates the strong effects of ROS and transient oxygenation on the biogeochemistry of intertidal sediments.
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Affiliation(s)
- Marit R van Erk
- Max Planck Institute for Marine Microbiology, Bremen, Germany. .,Department of Earth Sciences, Utrecht University, Utrecht, The Netherlands.
| | | | - Chyrene Moncada
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Subhajit Basu
- Max Planck Institute for Marine Microbiology, Bremen, Germany.,School of Health Sciences and Technology (SoHST), University of Petroleum and Energy Studies (UPES), Dehradun, Uttarakhand, 248007, India
| | - Colleen M Hansel
- Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
| | - Dirk de Beer
- Max Planck Institute for Marine Microbiology, Bremen, Germany
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11
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Sodium New Houttuyfonate Inhibits Cancer-Promoting Fusobacterium nucleatum (Fn) to Reduce Colorectal Cancer Progression. Cancers (Basel) 2022; 14:cancers14246111. [PMID: 36551597 PMCID: PMC9775898 DOI: 10.3390/cancers14246111] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 12/07/2022] [Accepted: 12/08/2022] [Indexed: 12/14/2022] Open
Abstract
Colorectal cancer (CRC) is a major cause of morbidity and mortality worldwide. Recent studies showed that the common anaerobe Fusobacterium nucleatum (Fn) is closely associated with a higher risk for carcinogenesis, metastasis, and chemoresistance of CRC. However, there is no specific antimicrobial therapy for CRC treatment. Herbal medicine has a long history of treating diseases with remarkable effects and is attracting extensive attention. In this study, we tested six common phytochemicals for their antimicrobial activities against Fn and whether anti-Fn phytochemicals can modulate CRC development associated with Fn. Among these antimicrobials, we found that SNH showed the highest antimicrobial activity and little cytotoxicity toward cancer cells and normal cells in vitro and in vivo. Mechanistically, SNH may target membrane-associated FadA, leading to FadA oligomerization, membrane fragmentation and permeabilization. More importantly, SNH blocked the tumor-promoting activity of Fn and Fn-associated cancer-driven inflammation, thus improving the intestinal barrier damaged by Fn. SNH reduced Fn load in the CRC-cells-derived mice xenografts with Fn inoculation and significantly inhibited CRC progression. Our data suggest that SNH could be used for an antimicrobial therapy that inhibits Fn and cancer-driven inflammation of CRC. Our results provide an important foundation for future gut microbiota-targeted clinical treatment of CRC.
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12
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Kim HJ, Mireles DeWitt CA, Park JW. Application of ohmic heating for accelerating Pacific whiting fish sauce fermentation. Lebensm Wiss Technol 2022. [DOI: 10.1016/j.lwt.2022.114299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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13
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Wang C, Cancino A, Baste J, Marten D, Joshi AA, Nasreen A, Bhushan A. Causative Role of Anoxic Environment in Bacterial Regulation of Human Intestinal Function. Cell Mol Bioeng 2022; 15:493-504. [PMID: 36444344 PMCID: PMC9700550 DOI: 10.1007/s12195-022-00735-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 08/11/2022] [Indexed: 11/03/2022] Open
Abstract
Introduction Life on Earth depends on oxygen; human tissues require oxygen signaling, whereas many microorganisms, including bacteria, thrive in anoxic environments. Despite these differences, human tissues and bacteria coexist in close proximity to each other such as in the intestine. How oxygen governs intestinal-bacterial interactions remains poorly understood. Methods To address to this gap, we created a dual-oxygen environment in a microfluidic device to study the role of oxygen in regulating the regulation of intestinal enzymes and proteins by gut bacteria. Two-layer microfluidic devices were designed using a fluid transport model and fabricated using soft lithography. An oxygen-sensitive material was integrated to determine the oxygen levels. The intestinal cells were cultured in the upper chamber of the device. The cells were differentiated, upon which bacterial strains, a facultative anaerobe, Escherichia coli Nissle 1917, and an obligate anaerobe, Bifidobacterium Adolescentis, were cultured with the intestinal cells. Results The microfluidic device successfully established a dual-oxygen environment. Of particular importance in our findings was that both strains significantly upregulated mucin proteins and modulated several intestinal transporters and transcription factors but only under the anoxic-oxic oxygen gradient, thus providing evidence of the role of oxygen on bacterial-epithelial signaling. Conclusions Our work that integrates cell and molecular biology with bioengineering presents a novel strategy to engineer an accessible experimental system to provide tailored oxygenated environments. The work could provide new avenues to study intestine-microbiome signaling and intestinal tissue engineering, as well as a novel perspective on the indirect effects of gut bacteria on tissues including tumors. Supplementary Information The online version contains supplementary material available at 10.1007/s12195-022-00735-x.
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Affiliation(s)
- Chengyao Wang
- Department of Biomedical Engineering, Illinois Institute of Technology, 3255 S. Dearborn Street, Wishnick Hall, Chicago, IL 60616 USA
| | - Andrea Cancino
- Department of Biomedical Engineering, Illinois Institute of Technology, 3255 S. Dearborn Street, Wishnick Hall, Chicago, IL 60616 USA
| | - Jasmine Baste
- Department of Biomedical Engineering, Illinois Institute of Technology, 3255 S. Dearborn Street, Wishnick Hall, Chicago, IL 60616 USA
| | - Daniel Marten
- Department of Biomedical Engineering, Illinois Institute of Technology, 3255 S. Dearborn Street, Wishnick Hall, Chicago, IL 60616 USA
| | - Advait Anil Joshi
- Department of Biomedical Engineering, Illinois Institute of Technology, 3255 S. Dearborn Street, Wishnick Hall, Chicago, IL 60616 USA
| | - Amreen Nasreen
- Department of Biomedical Engineering, Illinois Institute of Technology, 3255 S. Dearborn Street, Wishnick Hall, Chicago, IL 60616 USA
| | - Abhinav Bhushan
- Department of Biomedical Engineering, Illinois Institute of Technology, 3255 S. Dearborn Street, Wishnick Hall, Chicago, IL 60616 USA
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14
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Li J, Ran X, Zhou M, Wang K, Wang H, Wang Y. Oxidative stress and antioxidant mechanisms of obligate anaerobes involved in biological waste treatment processes: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 838:156454. [PMID: 35667421 DOI: 10.1016/j.scitotenv.2022.156454] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 05/23/2022] [Accepted: 05/31/2022] [Indexed: 06/15/2023]
Abstract
In-depth understanding of the molecular mechanisms and physiological consequences of oxidative stress is still limited for anaerobes. Anaerobic biotechnology has become widely accepted by the wastewater/sludge industry as a better alternative to more conventional but costly aerobic processes. However, the functional anaerobic microorganisms used in anaerobic biotechnology are frequently hampered by reactive oxygen/nitrogen species (ROS/RNS)-mediated oxidative stress caused by exposure to stressful factors (e.g., oxygen and heavy metals), which negatively impact treatment performance. Thus, identifying stressful factors and understanding antioxidative defense mechanisms of functional obligate anaerobes are crucial for the optimization of anaerobic bioprocesses. Herein, we present a comprehensive overview of oxidative stress and antioxidant mechanisms of obligate anaerobes involved in anaerobic bioprocesses; as examples, we focus on anaerobic ammonium oxidation bacteria and methanogenic archaea. We summarize the primary stress factors in anaerobic bioprocesses and the cellular antioxidant defense systems of functional anaerobes, a consortia of enzymatic and nonenzymatic mechanisms. The dual role of ROS/RNS in cellular processes is elaborated; at low concentrations, they have vital cell signaling functions, but at high concentrations, they cause oxidative damage. Finally, we highlight gaps in knowledge and future work to uncover antioxidant and damage repair mechanisms in obligate anaerobes. This review provides in-depth insights and guidance for future research on oxidative stress of obligate anaerobes to boost the accurate regulation of anaerobic bioprocesses in challenging and changing operating conditions.
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Affiliation(s)
- Jia Li
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai 200092, China
| | - Xiaochuan Ran
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai 200092, China
| | - Mingda Zhou
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai 200092, China
| | - Kaichong Wang
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai 200092, China
| | - Han Wang
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai 200092, China.
| | - Yayi Wang
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai 200092, China
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15
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Dandapani H, Kankaanpää P, Jones PR, Kallio P. A Plasmid-Based Fluorescence Reporter System for Monitoring Oxidative Damage in E. coli. SENSORS (BASEL, SWITZERLAND) 2022; 22:6334. [PMID: 36080791 PMCID: PMC9459809 DOI: 10.3390/s22176334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 08/11/2022] [Accepted: 08/17/2022] [Indexed: 06/15/2023]
Abstract
Quantitating intracellular oxidative damage caused by reactive oxygen species (ROS) is of interest in many fields of biological research. The current systems primarily rely on supplemented oxygen-sensitive substrates that penetrate the target cells, and react with ROS to produce signals that can be monitored with spectroscopic or imaging techniques. The objective here was to design a new non-invasive analytical strategy for measuring ROS-induced damage inside living cells by taking advantage of the native redox sensor system of E. coli. The developed plasmid-based sensor relies on an oxygen-sensitive transcriptional repressor IscR that controls the expression of a fluorescent marker in vivo. The system was shown to quantitatively respond to oxidative stress induced by supplemented H2O2 and lowered cultivation temperatures. Comparative analysis with fluorescence microscopy further demonstrated that the specificity of the reporter system was equivalent to the commercial chemical probe (CellROX). The strategy introduced here is not dependent on chemical probes, but instead uses a fluorescent expression system to detect enzyme-level oxidative damage in microbial cells. This provides a cheap and simple means for analysing enzyme-level oxidative damage in a biological context in E. coli.
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Affiliation(s)
- Hariharan Dandapani
- Molecular Plant Biology, Department of Life Technologies, University of Turku, FI-20014 Turku, Finland
| | - Pasi Kankaanpää
- Turku BioImaging and Turku Bioscience Centre, University of Turku, FI-20014 Turku, Finland
- Turku BioImaging and Turku Bioscience Centre, Åbo Akademi University, FI-20500 Turku, Finland
| | - Patrik R. Jones
- Molecular Plant Biology, Department of Life Technologies, University of Turku, FI-20014 Turku, Finland
- Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London SW7 2BX, UK
| | - Pauli Kallio
- Molecular Plant Biology, Department of Life Technologies, University of Turku, FI-20014 Turku, Finland
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16
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Abdollahi M, Al Sbei S, Rosenbaum MA, Harnisch F. The oxygen dilemma: The challenge of the anode reaction for microbial electrosynthesis from CO2. Front Microbiol 2022; 13:947550. [PMID: 35992647 PMCID: PMC9381829 DOI: 10.3389/fmicb.2022.947550] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 07/06/2022] [Indexed: 11/13/2022] Open
Abstract
Microbial electrosynthesis (MES) from CO2 provides chemicals and fuels by driving the metabolism of microorganisms with electrons from cathodes in bioelectrochemical systems. These microorganisms are usually strictly anaerobic. At the same time, the anode reaction of bioelectrochemical systems is almost exclusively water splitting through the oxygen evolution reaction (OER). This creates a dilemma for MES development and engineering. Oxygen penetration to the cathode has to be excluded to avoid toxicity and efficiency losses while assuring low resistance. We show that this dilemma derives a strong need to identify novel reactor designs when using the OER as an anode reaction or to fully replace OER with alternative oxidation reactions.
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Affiliation(s)
- Maliheh Abdollahi
- Department of Environmental Microbiology, UFZ-Helmholtz Centre for Environmental Research, Leipzig, Germany
| | - Sara Al Sbei
- Bio Pilot Plant, Leibniz Institute for Natural Product Research and Infection Biology - Hans-Knöll Institute, Jena, Germany
| | - Miriam A. Rosenbaum
- Bio Pilot Plant, Leibniz Institute for Natural Product Research and Infection Biology - Hans-Knöll Institute, Jena, Germany
- Faculty of Biological Sciences, Friedrich Schiller University Jena, Jena, Germany
| | - Falk Harnisch
- Department of Environmental Microbiology, UFZ-Helmholtz Centre for Environmental Research, Leipzig, Germany
- *Correspondence: Falk Harnisch,
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17
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Landis GN, Riggan L, Bell HS, Vu W, Wang T, Wang I, Tejawinata FI, Ko S, Tower J. Mifepristone Increases Life Span in Female Drosophila Without Detectable Antibacterial Activity. FRONTIERS IN AGING 2022; 3:924957. [PMID: 35935727 PMCID: PMC9354577 DOI: 10.3389/fragi.2022.924957] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 06/20/2022] [Indexed: 12/04/2022]
Abstract
Mifepristone dramatically increases the life span of mated female Drosophila while reducing the expression of innate immune response genes. Previous results indicated that mifepristone also reduced the load of aero-tolerant bacteria in mated females. Experiments were conducted to further investigate the possible role of bacteria in mifepristone life span effects. Life span was assayed in flies grown from sterilized eggs on autoclaved media and in normally cultured controls in two independent assays. Sterilization increased mated female life span (+8.3% and +57%, respectively), and the effect of mifepristone was additive (+53% and +93%, respectively). High-throughput sequencing of 16S sequences revealed that sterilization reduced the abundance of multiple species and the classes Bacteroidia, Bacilli, Actinobacteria, and Cytophagia. By contrast, mifepristone caused no decreases and instead increased the abundance of three species. Five aero-tolerant bacterial species were cultured from extracts of mated female flies, including both Gram-positive and Gram-negative species (Acetobacter sicerae, Enterococcus faecalis, Lactobacillus plantarum, Serratia rubidea, and Paenibacillus glucanolyticus). There was no detectable effect of mifepristone on the growth of these bacteria in vitro, indicating that mifepristone does not have a direct antibiotic effect. To test if antibiotics could mimic the effects of mifepristone in vivo, mated female flies were treated throughout adult life span with high concentrations of the individual antibiotics doxycycline, ampicillin, kanamycin, and streptomycin, in replicate experiments. No significant effect on life span was observed for ampicillin, kanamycin, or streptomycin, and an inconsistent benefit was observed for doxycycline. Finally, supplementation of media with Enterococcus faecalis did not alter adult female life span in the presence or absence of mifepristone. Taken together, the results indicate the life span benefits of mifepristone are not due to an antibiotic effect.
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Affiliation(s)
| | | | | | | | | | | | | | | | - John Tower
- Molecular and Computational Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, CA, United States
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18
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Lee EH, Lee SW, Seo Y, Deng YH, Lim YJ, Kwon HB, Park K, Kong H, Kim MJ. Manganese Oxide Nanozyme-Doped Diatom for Safe and Efficient Treatment of Peri-Implantitis. ACS APPLIED MATERIALS & INTERFACES 2022; 14:27634-27650. [PMID: 35638645 DOI: 10.1021/acsami.2c05166] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Peri-implantitis is a major cause of dental implant failure. Bacterial biofilm contamination on the implant induces surrounding bone resorption and soft tissue inflammation, leading to severe deterioration of oral health. However, conventional biofilm removal procedures, such as mechanical decontamination and antiseptic application, are not effective enough to induce reosseointegration on decontaminated implant surfaces. This is due to (1) incomplete decontamination of the biofilm from inaccessible areas and (2) physicochemical alteration of implant surfaces caused by decontamination procedures. Herein, a safe and effective therapeutic approach for peri-implantitis is developed, which involves decontamination of implant-bound biofilms using the kinetic energy of microsized oxygen bubbles generated from the catalytic reaction between hydrogen peroxide (H2O2) and manganese oxide (MnO2) nanozyme sheet-doped silica diatom microparticles (Diatom Microbubbler, DM). Rapidly moving microsized DM particles are able to penetrate narrow spaces between implant screws, exerting just the right amount of force to entirely destroy biofilms without harming the surrounding mucosa or implant surfaces, as opposed to conventional antiseptics such as chlorhexidine or 3% H2O2 when used alone. Consequently, decontamination with DM facilitates successful reosseointegration on the peri-implantitis-affected implant surface. In summary, our new DM-based therapeutic approach will become a promising alternative to resolve clinically challenging aspects of peri-implantitis.
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Affiliation(s)
- Eun-Hyuk Lee
- Department of Prosthodontics, School of Dentistry and Dental Research Institute, Seoul National University, Seoul 110-749, South Korea
| | - Sang-Woo Lee
- Department of Physiology, School of Dentistry and Dental Research Institute, Seoul National University, Seoul 110-749, South Korea
| | - Yongbeom Seo
- Department of Chemical and Biomolecular Engineering, Carle Illinois College of Medicine, Department of Pathobiology, Carl R. Woese Institute for Genomic Biology, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Yu-Heng Deng
- Department of Chemical and Biomolecular Engineering, Carle Illinois College of Medicine, Department of Pathobiology, Carl R. Woese Institute for Genomic Biology, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Young-Jun Lim
- Department of Prosthodontics, School of Dentistry and Dental Research Institute, Seoul National University, Seoul 110-749, South Korea
| | - Ho-Beom Kwon
- Department of Prosthodontics, School of Dentistry and Dental Research Institute, Seoul National University, Seoul 110-749, South Korea
| | - Kyungpyo Park
- Department of Physiology, School of Dentistry and Dental Research Institute, Seoul National University, Seoul 110-749, South Korea
| | - Hyunjoon Kong
- Department of Chemical and Biomolecular Engineering, Carle Illinois College of Medicine, Department of Pathobiology, Carl R. Woese Institute for Genomic Biology, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Myung-Joo Kim
- Department of Prosthodontics, School of Dentistry and Dental Research Institute, Seoul National University, Seoul 110-749, South Korea
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19
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Huang M, Zhu L, Feng L, Zhan L, Zhao Y, Chen X. Reforming Nitrate Metabolism for Enhancing L-Arginine Production in Corynebacterium crenatum Under Oxygen Limitation. Front Microbiol 2022; 13:834311. [PMID: 35356524 PMCID: PMC8959459 DOI: 10.3389/fmicb.2022.834311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Accepted: 02/10/2022] [Indexed: 11/13/2022] Open
Abstract
Various amino acids are widely manufactured using engineered bacteria. It is crucial to keep the dissolved oxygen at a certain level during fermentation, but accompanied by many disadvantages, such as high energy consumption, reactive oxygen species, and risk of phage infections. Thus, anaerobic production of amino acids is worth attempting. Nitrate respiration systems use nitrate as an electron acceptor under anoxic conditions, which is different from the metabolism of fermentation and can produce energy efficiently. Herein, we engineered Corynebacterium crenatum to enhance L-arginine production under anaerobic conditions through strengthening nitrate respiration and reforming nitrogen flux. The construction of mutant strain produced up to 3.84 g/L L-arginine under oxygen limitation with nitrate, and this value was 131.33% higher than that produced by the control strain under limited concentrations of oxygen without nitrate. Results could provide fundamental information for improving L-arginine production by metabolic engineering of C. crenatum under oxygen limitation.
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Affiliation(s)
- Mingzhu Huang
- Department of Life Science, Jiangxi Normal University, Nanchang, China.,National R&D Center for Freshwater Fish Processing, Nanchang, China
| | - Lingfeng Zhu
- Department of Life Science, Jiangxi Normal University, Nanchang, China
| | - Lin Feng
- Department of Life Science, Jiangxi Normal University, Nanchang, China
| | - Li Zhan
- Department of Life Science, Jiangxi Normal University, Nanchang, China
| | - Yue Zhao
- Department of Life Science, Jiangxi Normal University, Nanchang, China
| | - Xuelan Chen
- Department of Life Science, Jiangxi Normal University, Nanchang, China.,National R&D Center for Freshwater Fish Processing, Nanchang, China.,Key Laboratory of Functional Small Organic Molecule of Ministry of Education, Jiangxi Normal University, Nanchang, China
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20
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Chen R, Liu H, Zhang P, Ma J, Jin M. Co-response of Fe-reducing/oxidizing bacteria and Fe species to the dynamic redox cycles of natural sediment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 815:152953. [PMID: 34999076 DOI: 10.1016/j.scitotenv.2022.152953] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 12/29/2021] [Accepted: 01/03/2022] [Indexed: 06/14/2023]
Abstract
Fe(III)-reducing bacteria (FRB) and Fe(II)-oxidizing bacteria (FOB) play essential roles in the biogeochemical cycling of iron (Fe). Although the redox transformation of Fe species mediated by FRB/FOB has been extensively studied, the co-responses of FRB and FOB and Fe species transformation in natural sediment under dynamic redox conditions are poorly known. This study explored the variations of potential FRB and FOB abundances and Fe species transformation in natural sediment during successive anoxic-oxic-anoxic-oxic-anoxic cycles. Compared with the pristine sediment sample, the FRB abundance increased 121-793% (initial: (2.6 ± 0.6) × 107 copies/g) in the anoxic stages, while it decreased by 38-64% in the oxic stages. The increase in FRB abundance was ascribed to energy gain of FRB from the reduction of the amorphous Fe(III) (Fe(III)am) and the crystalline Fe(III) (Fe(III)cry) to the aqueous Fe(II) (Fe(II)aq), the adsorbed Fe(II) (Fe(II)ad) and the amorphous Fe(II) (Fe(II)am), while the decrease was attributed to the oxidative stress caused by the reactive oxidant produced from the abiotic oxidation of Fe(II)aq, Fe(II)ad and Fe(II)am to Fe(III)am and Fe(III)cry. The FOB abundance decreased 38-44% (initial: (5 ± 1.8) × 107 copies/g) in the second and third anoxic stages, while slightly fluctuated in the oxic periods. This observation was contrary to the variation of FRB, which might be attributed to the strong resistance to oxidative stress of FOB and its ability to obtain energy under oxic conditions. Although the functions of FRB and FOB were impaired during anoxic-oxic cycles, the transformation of Fe(II)/Fe(III) was not immediately affected, which may be related to the residual reactivity of dead bacteria and the bio-availability of Fe(II)/Fe(III) species. In the anoxic-oxic alternation process, the iron cycle is mainly the mutual transformation between Fe(II)aq, Fe(II)ad, Fe(II)am and Fe(III)am, Fe(III)cry. This finding deepens our understanding of the biogeochemical cycling of Fe in the redox-dynamic environments.
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Affiliation(s)
- Rong Chen
- School of Environmental Studies, China University of Geosciences, 68 Jincheng Street, East Lake High-Tech Development Zone, Wuhan, Hubei 430078, PR China
| | - Hui Liu
- School of Environmental Studies, China University of Geosciences, 68 Jincheng Street, East Lake High-Tech Development Zone, Wuhan, Hubei 430078, PR China; State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 68 Jincheng Street, East Lake High-Tech Development Zone, Wuhan, Hubei 430078, PR China.
| | - Peng Zhang
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 68 Jincheng Street, East Lake High-Tech Development Zone, Wuhan, Hubei 430078, PR China
| | - Jie Ma
- School of Environmental Studies, China University of Geosciences, 68 Jincheng Street, East Lake High-Tech Development Zone, Wuhan, Hubei 430078, PR China
| | - Menggui Jin
- School of Environmental Studies, China University of Geosciences, 68 Jincheng Street, East Lake High-Tech Development Zone, Wuhan, Hubei 430078, PR China
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21
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Li C, Humayun M, Walker GM, Park KY, Connors B, Feng J, Pellitteri Hahn MC, Scarlett CO, Li J, Feng Y, Clark RL, Hefti H, Schrope J, Venturelli OS, Beebe DJ. Under-Oil Autonomously Regulated Oxygen Microenvironments: A Goldilocks Principle-Based Approach for Microscale Cell Culture. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2104510. [PMID: 35118834 PMCID: PMC8981459 DOI: 10.1002/advs.202104510] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 11/20/2021] [Indexed: 05/14/2023]
Abstract
Oxygen levels in vivo are autonomously regulated by a supply-demand balance, which can be altered in disease states. However, the oxygen levels of in vitro cell culture systems, particularly microscale cell culture, are typically dominated by either supply or demand. Further, the oxygen microenvironment in these systems is rarely monitored or reported. Here, a method to establish and dynamically monitor autonomously regulated oxygen microenvironments (AROM) using an oil overlay in an open microscale cell culture system is presented. Using this method, the oxygen microenvironment is dynamically regulated via the supply-demand balance of the system. Numerical simulation and experimental validation of oxygen transport within multi-liquid-phase, microscale culture systems involving a variety of cell types, including mammalian, fungal, and bacterial cells are presented. Finally, AROM is applied to establish a coculture between cells with disparate oxygen demands-primary intestinal epithelial cells (oxygen consuming) and Bacteroides uniformis (an anaerobic species prevalent in the human gut).
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Affiliation(s)
- Chao Li
- Carbone Cancer CenterUniversity of Wisconsin‐MadisonMadisonWI53705USA
| | - Mouhita Humayun
- Department of Biomedical EngineeringUniversity of Wisconsin‐MadisonMadisonWI53705USA
| | - Glenn M. Walker
- Department of Biomedical EngineeringUniversity of Mississippi UniversityMadisonMS38677USA
| | - Keon Young Park
- Department of SurgeryUniversity of California San FranciscoSan FranciscoCA94143USA
| | - Bryce Connors
- Department of BiochemistryUniversity of Wisconsin‐MadisonMadisonWI53706USA
- Department of Chemical and Biological EngineeringUniversity of Wisconsin‐MadisonMadisonWI53706USA
| | - Jun Feng
- Department of BiochemistryUniversity of Wisconsin‐MadisonMadisonWI53706USA
| | - Molly C. Pellitteri Hahn
- Analytical Instrumentation Center‐Mass Spec FacilitySchool of PharmacyUniversity of Wisconsin‐MadisonMadisonWI53705USA
| | - Cameron O. Scarlett
- Analytical Instrumentation Center‐Mass Spec FacilitySchool of PharmacyUniversity of Wisconsin‐MadisonMadisonWI53705USA
| | - Jiayi Li
- Department of Biomedical EngineeringUniversity of Wisconsin‐MadisonMadisonWI53705USA
| | - Yanbo Feng
- Department of Biomedical EngineeringUniversity of Wisconsin‐MadisonMadisonWI53705USA
| | - Ryan L. Clark
- Department of BiochemistryUniversity of Wisconsin‐MadisonMadisonWI53706USA
| | - Hunter Hefti
- Department of Biomedical EngineeringUniversity of Wisconsin‐MadisonMadisonWI53705USA
| | - Jonathan Schrope
- School of Medicine and Public HealthUniversity of Wisconsin‐MadisonMadisonWI53726USA
| | - Ophelia S. Venturelli
- Department of BiochemistryUniversity of Wisconsin‐MadisonMadisonWI53706USA
- Department of Chemical and Biological EngineeringUniversity of Wisconsin‐MadisonMadisonWI53706USA
- Department of BacteriologyUniversity of Wisconsin‐MadisonMadisonWI53706USA
| | - David J. Beebe
- Carbone Cancer CenterUniversity of Wisconsin‐MadisonMadisonWI53705USA
- Department of Biomedical EngineeringUniversity of Wisconsin‐MadisonMadisonWI53705USA
- Department of Pathology and Laboratory MedicineUniversity of Wisconsin‐MadisonMadisonWI53705USA
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22
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Tomusiak-Plebanek A, Mruk M, Rząca S, Strus M, Arent Z. In Vitro assessment of anti-Campylobacter activity of lactobacillus strains isolated from canine rectal swabs. BMC Vet Res 2022; 18:112. [PMID: 35317800 PMCID: PMC8939066 DOI: 10.1186/s12917-022-03204-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 02/28/2022] [Indexed: 11/23/2022] Open
Abstract
Background Campylobacteriosis is currently the most frequently reported zoonosis. Dogs, especially puppies or those with diarrhea, are considered a possible source of human infection. Probiotic bacteria, such as Lactobacillus species, seem to be a valuable tool in controlling of intestinal pathogenic microorganisms in dogs. The main purpose of this study was to assess the anti-Campylobacter activity and some probiotic properties, like ability to produce H2O2, bile salt and low pH tolerance of Lactobacillus strains isolated from gastrointestinal tract of healthy dogs. Results A total of 39 rectal swabs derived from healthy dogs and 19 from dogs with diarrhea were examined to detect Lactobacillus and Campylobacter bacteria respectively. In total, 30 strains of Lactobacillus genus and four strains of Campylobacter genus were isolated and identified. Of the 30 strains of Lactobacillus, 22 showed an inhibitory effect towards Campylobacter. Four strains with the strongest antagonism towards Campylobacter bacteria (L. salivarius 25 K/L/1, L. rhamnosus 42 K/L/2, L. sakei 50 K/L/1 and L. agilis 55 K/L/1) were selected to assess their potential probiotic traits. Three out of four analyzed strains produced extracellular H2O2. All displayed very good or moderate survival at pH 3.0 and 2.0 and showed high tolerance to 0.5% and 1% bile salts. Conclusions Among selected Lactobacillus strains, all may have a potential probiotic application in reducing Campylobacter spp. in dogs and thus prevent transmission of infection to humans, although the best candidate for probiotic seems to be L. sakei 50 K/L/1. Further in vitro and in vivo studies are needed.
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Affiliation(s)
- Anna Tomusiak-Plebanek
- Chair of Microbiology, Jagiellonian University Medical College, 31-121 18 Czysta Street, Krakow, Poland.
| | - Martyna Mruk
- University Centre of Veterinary Medicine, University of Agriculture, 30-059, Krakow, Poland
| | - Sybilla Rząca
- University Centre of Veterinary Medicine, University of Agriculture, 30-059, Krakow, Poland
| | - Magdalena Strus
- Chair of Microbiology, Jagiellonian University Medical College, 31-121 18 Czysta Street, Krakow, Poland
| | - Zbigniew Arent
- University Centre of Veterinary Medicine, University of Agriculture, 30-059, Krakow, Poland
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23
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Oborník M. Organellar Evolution: A Path from Benefit to Dependence. Microorganisms 2022; 10:microorganisms10010122. [PMID: 35056571 PMCID: PMC8781833 DOI: 10.3390/microorganisms10010122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 01/04/2022] [Accepted: 01/05/2022] [Indexed: 12/10/2022] Open
Abstract
Eukaryotic organelles supposedly evolved from their bacterial ancestors because of their benefits to host cells. However, organelles are quite often retained, even when the beneficial metabolic pathway is lost, due to something other than the original beneficial function. The organellar function essential for cell survival is, in the end, the result of organellar evolution, particularly losses of redundant metabolic pathways present in both the host and endosymbiont, followed by a gradual distribution of metabolic functions between the organelle and host. Such biological division of metabolic labor leads to mutual dependence of the endosymbiont and host. Changing environmental conditions, such as the gradual shift of an organism from aerobic to anaerobic conditions or light to dark, can make the original benefit useless. Therefore, it can be challenging to deduce the original beneficial function, if there is any, underlying organellar acquisition. However, it is also possible that the organelle is retained because it simply resists being eliminated or digested untill it becomes indispensable.
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Affiliation(s)
- Miroslav Oborník
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, 37005 České Budějovice, Czech Republic;
- Faculty of Science, University of South Bohemia, 37005 České Budějovice, Czech Republic
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24
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Timmis K, Hallsworth JE. The darkest microbiome-a post-human biosphere. Microb Biotechnol 2022; 15:176-185. [PMID: 34843168 PMCID: PMC8719803 DOI: 10.1111/1751-7915.13976] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Accepted: 11/11/2021] [Indexed: 01/05/2023] Open
Abstract
Microbial technology is exceptional among human activities and endeavours in its range of applications that benefit humanity, even exceeding those of chemistry. What is more, microbial technologists are among the most creative scientists, and the scope of the field continuously expands as new ideas and applications emerge. Notwithstanding this diversity of applications, given the dire predictions for the fate of the surface biosphere as a result of current trajectories of global warming, the future of microbial biotechnology research must have a single purpose, namely to help secure the future of life on Earth. Everything else will, by comparison, be irrelevant. Crucially, microbes themselves play pivotal roles in climate (Cavicchioli et al., Nature Revs Microbiol 17: 569-586, 2019). To enable realization of their full potential in humanity's effort to survive, development of new and transformative global warming-relevant technologies must become the lynchpin of microbial biotechnology research and development. As a consequence, microbial biotechnologists must consider constraining their usual degree of freedom, and re-orienting their focus towards planetary-biosphere exigences. And they must actively seek alliances and synergies with others to get the job done as fast as humanly possible; they need to enthusiastically embrace and join the global effort, subordinating where necessary individual aspirations to the common good (the amazing speed with which new COVID-19 diagnostics and vaccines were developed and implemented demonstrates what is possible given creativity, singleness of purpose and funding). In terms of priorities, some will be obvious, others less so, with some only becoming revealed after dedicated effort yields new insights/opens new vistas. We therefore refrain from developing a priority list here. Rather, we consider what is likely to happen to the Earth's biosphere if we (and the rest of humanity) fail to rescue it. We do so with the aim of galvanizing the formulation and implementation of strategic and financial science policy decisions that will maximally stimulate the development of relevant new microbial technologies, and maximally exploit available technologies, to repair existing environmental damage and mitigate against future deterioration.
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Affiliation(s)
- Kenneth Timmis
- Institute of MicrobiologyTechnical University of BraunschweigBraunschweigGermany
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25
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Fallon M, Conway J, Kennedy S, Kumar S, Daniels S, Humphreys H. The effect of cold plasma operating parameters on the production of reactive oxygen and nitrogen species and the resulting antibacterial and antibiofilm efficiency. PLASMA MEDICINE 2022. [DOI: 10.1615/plasmamed.2022043043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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26
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Price EE, Román-Rodríguez F, Boyd JM. Bacterial approaches to sensing and responding to respiration and respiration metabolites. Mol Microbiol 2021; 116:1009-1021. [PMID: 34387370 DOI: 10.1111/mmi.14795] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 08/03/2021] [Accepted: 08/09/2021] [Indexed: 11/29/2022]
Abstract
Bacterial respiration of diverse substrates is a primary contributor to the diversity of life. Respiration also drives alterations in the geosphere and tethers ecological nodes together. It provides organisms with a means to dissipate reductants and generate potential energy in the form of an electrochemical gradient. Mechanisms have evolved to sense flux through respiratory pathways and sense the altered concentrations of respiration substrates or byproducts. These genetic regulatory systems promote efficient utilization of respiration substrates, as well as fine tune metabolism to promote cellular fitness and negate the accumulation of toxic byproducts. Many bacteria can respire one or more chemicals, and these regulatory systems promote the prioritization of high energy metabolites. Herein we focus on regulatory paradigms and discuss systems that sense the concentrations of respiration substrates and flux through respiratory pathways. This is a broad field of study, and therefore we focus on key fundamental and recent developments and highlight specific systems that capture the diversity of sensing mechanisms.
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Affiliation(s)
- Erin E Price
- Department of Biochemistry & Microbiology, Rutgers, The State University of New Jersey, New Brunswick, NJ, 08901, USA
| | - Franklin Román-Rodríguez
- Department of Biochemistry & Microbiology, Rutgers, The State University of New Jersey, New Brunswick, NJ, 08901, USA
| | - Jeffrey M Boyd
- Department of Biochemistry & Microbiology, Rutgers, The State University of New Jersey, New Brunswick, NJ, 08901, USA
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27
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Zhuang H, Lee PH, Wu Z, Jing H, Guan J, Tang X, Tan GYA, Leu SY. Genomic driven factors enhance biocatalyst-related cellulolysis potential in anaerobic digestion. BIORESOURCE TECHNOLOGY 2021; 333:125148. [PMID: 33878497 DOI: 10.1016/j.biortech.2021.125148] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 04/01/2021] [Accepted: 04/04/2021] [Indexed: 06/12/2023]
Abstract
Anaerobic digestion (AD) is a promising technology to recover bioenergy from biodegradable biomass, including cellulosic wastes. Through a few fractionation/separation techniques, cellulose has demonstrated its potential in AD, but the performance of the process is rather substrate-specific, as cellulolysis bacteria are sensitive to the enzyme-substrate interactions. Cellulosome is a self-assembled enzyme complex with many functionalized modules in the bacteria which has been gradually studied, however the genomic fingerprints of the culture-specific cellulosome in AD are relatively unclear especially under processing conditions. To clarify the key factors affecting the cellulosome induced cellulolysis, this review summarized the most recent publications of AD regarding the fates of cellulose, sources and functional genes of cellulosome, and omics methods for functional analyses. Different processes for organic treatment including applying food grinds in sewer, biomass valorization, cellulose fractionation, microaeration, and enzymatic hydrolysis enhanced fermentation, were highlighted to support the sustainable development of AD technology.
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Affiliation(s)
- Huichuan Zhuang
- Dept. of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong; Department of Civil Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong
| | - Po-Heng Lee
- Dept. of Civil and Environmental Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ, UK
| | - Zhuoying Wu
- Dept. of Civil and Environmental Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ, UK
| | - Houde Jing
- Dept. of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
| | - Jianyu Guan
- Dept. of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
| | - Xiaojing Tang
- Dept. of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
| | - Giin-Yu Amy Tan
- Department of Civil Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong
| | - Shao-Yuan Leu
- Dept. of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong.
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28
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Hou S, Zhang J, Ma X, Hong Q, Fang L, Zheng G, Huang J, Gao Y, Xu Q, Zhuang X, Song X. Role of rgsA in Oxidative Stress Resistance in Pseudomonas aeruginosa. Curr Microbiol 2021; 78:3133-3141. [PMID: 34185129 DOI: 10.1007/s00284-021-02580-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Accepted: 06/13/2021] [Indexed: 10/21/2022]
Abstract
Pseudomonas aeruginosa is a common opportunistic pathogen that causes infections in vulnerable patients including those with metabolic disorders, hematologic diseases, and malignancies, and in those who have undergone surgery. In addition, P. aeruginosa exhibits high intrinsic resistance to numerous antibiotics and tends to form biofilms rendering it even more refractory to treatment. Among the mechanisms used by P. aeruginosa to adapt to environmental stresses are those involving small regulatory RNAs (sRNAs), which are 40-500 nucleotides long and are ubiquitous in bacteria. sRNAs play important regulatory roles in various vital processes in diverse bacteria, with their quantity and diversity of regulatory functions exceeding those of proteins. In this study, we show that deletion of the sRNA, rgsA, decreased the growth rate of P. aeruginosa. Furthermore, ΔrgsA P. aeruginosa exhibited decreased ability to resist the stress induced by exposure to different concentrations and durations of peroxides in both planktonic and biofilm growth modes compared with the wild-type strain. These results highlight the role of rgsA in the defense of P. aeruginosa against oxidative stress.
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Affiliation(s)
- Shuyi Hou
- Department of Clinical Laboratory, Xiang'an Hospital of Xiamen University, 2000 Xiangan Dong Road, Xiamen, 361000, Fujian, China
| | - Jiaqin Zhang
- Department of Clinical Laboratory, The First Affiliated Hospital of Xiamen University, 55 Zhenhai Road, Xiamen, 361000, Fujian, China. .,Xiamen Key Laboratory of Genetic Testing, 55 Zhenhai Road, Xiamen, 361000, Fujian, China.
| | - Xiaobo Ma
- Department of Clinical Laboratory, The First Affiliated Hospital of Xiamen University, 55 Zhenhai Road, Xiamen, 361000, Fujian, China
| | - Qiang Hong
- Department of Clinical Laboratory, The First Affiliated Hospital of Xiamen University, 55 Zhenhai Road, Xiamen, 361000, Fujian, China
| | - Lili Fang
- Department of Clinical Laboratory, The First Affiliated Hospital of Xiamen University, 55 Zhenhai Road, Xiamen, 361000, Fujian, China
| | - Gangsen Zheng
- Department of Clinical Laboratory, The First Affiliated Hospital of Xiamen University, 55 Zhenhai Road, Xiamen, 361000, Fujian, China
| | - Jiaming Huang
- Department of Clinical Laboratory, The Second Affiliated Hospital of Fujian Medical University, 34 Zhongshan North Road, Quanzhou, 362000, Fujian, China
| | - Yingchun Gao
- Department of Clinical Laboratory, The First People's Hospital of Xiaoshan District, 199 Shixin Nan Road, Hangzhou, 311200, Zhejiang, China
| | - Qiaoli Xu
- Department of Clinical Laboratory, Zhangzhou Affiliated Hospital of Fujian Medical University, 59 Shengli Road, Zhangzhou, 363000, Fujian, China
| | - Xinguo Zhuang
- Department of Clinical Laboratory, The First Affiliated Hospital of Xiamen University, 55 Zhenhai Road, Xiamen, 361000, Fujian, China
| | - Xiuyu Song
- Xiamen Blood Centre, 121 Hubin Nan Road, Xiamen, 361000, Fujian, China.
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29
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Wang Y, Lai CY, Wu M, Song Y, Hu S, Yuan Z, Guo J. Roles of Oxygen in Methane-dependent Selenate Reduction in a Membrane Biofilm Reactor: Stimulation or Suppression. WATER RESEARCH 2021; 198:117150. [PMID: 33910142 DOI: 10.1016/j.watres.2021.117150] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 04/03/2021] [Accepted: 04/10/2021] [Indexed: 05/22/2023]
Abstract
Although methane (CH4) has been proven to be able to serve as an electron donor for bio-reducing various oxidized contaminants (e.g., selenate (SeO42-)), little is known regarding the roles of oxygen in methane-based reduction processes. Here, a methane-based membrane biofilm reactor (MBfR) was established for evaluating the effects of oxygen supply rates on selenate reduction performance and microbial communities. The oxygen supply rate played a dual role (stimulatory or suppressive effect) in selenate reduction rates, depending on the presence or absence of dissolved oxygen (DO). Specifically, selenate reduction rate was substantially enhanced when an appropriate oxygen rate (e.g., 12 to 184 mg/L.d in this study) was supplied but with negligible DO. The highest selenate reduction rate (up to 34 mg-Se/L.d) was obtained under an oxygen supply rate of 184 mg/L.d. In contrast, excessive oxygen supply rate (626 mg/L.d) would significantly suppress selenate reduction rate under DO level of 3 mg/L. Accordingly, though the high oxygen supply rate (626 mg/L.d) would promote the expression of pmoA (5.9 × 109 copies g-1), the expression level of narG (a recognized gene to mediate selenate reduction) would be significantly downregulated (6.1 × 109 copies g-1), thus suppressing selenate reduction. In contrast, the expression of narG gene significantly increased to 2.8 × 1010 copies g-1, and the expression of pmoA gene could still maintain at 1.1 × 109 copies g-1 under an oxygen supply rate of 184 mg/L.d. High-throughput sequencing targeting 16S rRNA gene, pmoA, and narG collectively suggested Methylocystis acts as the major aerobic methanotroph, in synergy with Arthrobacter and Variovorax which likely jointly reduce selenate to selenite (SeO32-), and further to elemental selenium (Se0). Methylocystis was predominant in the biofilm regardless of variations of oxygen supply rates, while Arthrobacter and Variovorax were sensitive to oxygen fluctuation. These findings provide insights into the effects of oxygen on methane-dependent selenate reduction and suggest that it is feasible to achieve a higher selenate removal by regulating oxygen supply rates.
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Affiliation(s)
- Yulu Wang
- Advanced Water Management Centre, The University of Queensland, St Lucia, Brisbane, Queensland 4072, Australia
| | - Chun-Yu Lai
- Advanced Water Management Centre, The University of Queensland, St Lucia, Brisbane, Queensland 4072, Australia
| | - Mengxiong Wu
- Advanced Water Management Centre, The University of Queensland, St Lucia, Brisbane, Queensland 4072, Australia
| | - Yarong Song
- Advanced Water Management Centre, The University of Queensland, St Lucia, Brisbane, Queensland 4072, Australia
| | - Shihu Hu
- Advanced Water Management Centre, The University of Queensland, St Lucia, Brisbane, Queensland 4072, Australia
| | - Zhiguo Yuan
- Advanced Water Management Centre, The University of Queensland, St Lucia, Brisbane, Queensland 4072, Australia
| | - Jianhua Guo
- Advanced Water Management Centre, The University of Queensland, St Lucia, Brisbane, Queensland 4072, Australia.
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30
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Early-Life Immune System Maturation in Chickens Using a Synthetic Community of Cultured Gut Bacteria. mSystems 2021; 6:6/3/e01300-20. [PMID: 34006629 PMCID: PMC8269260 DOI: 10.1128/msystems.01300-20] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The gut microbiome is crucial for both maturation of the immune system and colonization resistance against enteric pathogens. Although chicken are important domesticated animals, the impact of their gut microbiome on the immune system is understudied. Therefore, we investigated the effect of microbiome-based interventions on host mucosal immune responses. Increased levels of IgA and IgY were observed in chickens exposed to maternal feces after hatching compared with strict hygienic conditions. This was accompanied by increased gut bacterial diversity as assessed by 16S rRNA gene amplicon sequencing. Cultivation work allowed the establishment of a collection of 43 bacterial species spanning 4 phyla and 19 families, including the first cultured members of 3 novel genera and 4 novel species that were taxonomically described. This resource is available at www.dsmz.de/chibac. A synthetic community consisting of nine phylogenetically diverse and dominant species from this collection was designed and found to be moderately efficient in boosting immunoglobulin levels when provided to chickens early in life. IMPORTANCE The immune system plays a crucial role in sustaining animal health. Its development is markedly influenced by early microbial colonization of the gastrointestinal tract. As chicken are fully dependent on environmental microbes after hatching, extensive hygienic measures in production facilities are detrimental to the microbiota, resulting in low colonization resistance against pathogens. To combat enteric infections, antibiotics are frequently used, which aggravates the issue by altering gut microbiota colonization. Intervention strategies based on cultured gut bacteria are proposed to influence immune responses in chicken.
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31
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Wu Z, Nguyen D, Lam TYC, Zhuang H, Shrestha S, Raskin L, Khanal SK, Lee PH. Synergistic association between cytochrome bd-encoded Proteiniphilum and reactive oxygen species (ROS)-scavenging methanogens in microaerobic-anaerobic digestion of lignocellulosic biomass. WATER RESEARCH 2021; 190:116721. [PMID: 33326896 DOI: 10.1016/j.watres.2020.116721] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 11/30/2020] [Accepted: 12/01/2020] [Indexed: 06/12/2023]
Abstract
Intermittent (every other day) microaerobic [picomolar oxygen by oxidation-reduction potential (ORP) set at +25 mV above anaerobic baseline] digestion of lignocellulosic biomass showed higher digestibility and better stability at a high organic loading rate (OLR) of 5 g volatile solids (VS)/L/d than that under strict anaerobic conditions. However, the microbial mechanisms supporting the delicate balance under microaeration remain underexplored. On the basis of our previous findings that microbial communities in replicate experiments were dominated by strains of the genus Proteiniphilum but contained diverse taxa of methanogenic archaea, here we recovered related genomes and reconstructed the putative metabolic pathways using a genome-centric metagenomic approach. The highly enriched Proteiniphilum strains were identified as efficient cellulolytic facultative bacterium, which directly degraded lignocellulose to carbon dioxide, formate, and acetate via aerobic respiration and anaerobic fermentation, alternatively. Moreover, high oxygen affinity cytochromes, bd-type terminal oxidases, in Proteiniphilum strains were found to be closely associated with such picomolar oxygen conditions, which has long been overlooked in anaerobic digestion. Furthermore, hydrogenotrophic methanogenesis was the prevalent pathway for methane production while Methanosarcina, Methanobrevibacter, and Methanocorpusculum were the dominant methanogens in the replicate experiments. Importantly, the two functional groups, namely cellulolytic facultative Proteiniphilum strains and methanogens, encoded various antioxidant enzymes. Energy-dependent reactive oxygen species (ROS) scavengers (superoxide reductase (SOR) and rubrerythrin (rbr) were ubiquitously present in different methanogenic taxa in response to replicate-specific ORP levels (-470, -450 and -475 mV). Collectively, cytochrome bd oxidase and ROS defenders may play roles in improving the digestibility and stability observed in intermittent microaerobic digestion.
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Affiliation(s)
- Zhuoying Wu
- Department of Civil and Environmental Engineering, Imperial College, London, The United Kingdom
| | - Duc Nguyen
- Department of Molecular Biosciences and Bioengineering, University of Hawai'i at Mānoa, Honolulu, HI 96822, USA
| | - Theo Y C Lam
- Department of Civil and Environmental Engineering, Imperial College, London, The United Kingdom; Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR
| | - Huichuan Zhuang
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR
| | - Shilva Shrestha
- Department of Civil and Environmental Engineering, University of Michigan, 1351 Beal Avenue, 107 EWRE Building, Ann Arbor, MI 48109-2125, USA
| | - Lutgarde Raskin
- Department of Civil and Environmental Engineering, University of Michigan, 1351 Beal Avenue, 107 EWRE Building, Ann Arbor, MI 48109-2125, USA
| | - Samir Kumar Khanal
- Department of Molecular Biosciences and Bioengineering, University of Hawai'i at Mānoa, Honolulu, HI 96822, USA.
| | - Po-Heng Lee
- Department of Civil and Environmental Engineering, Imperial College, London, The United Kingdom.
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32
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Thomas MD, Ewunkem AJ, Boyd S, Williams DK, Moore A, Rhinehardt KL, Van Beveren E, Yang B, Tapia A, Han J, Harrison SH, Graves JL. Too much of a good thing: Adaption to iron (II) intoxication in Escherichia coli. EVOLUTION MEDICINE AND PUBLIC HEALTH 2021; 9:53-67. [PMID: 33717488 PMCID: PMC7937436 DOI: 10.1093/emph/eoaa051] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Accepted: 11/30/2020] [Indexed: 12/22/2022]
Abstract
Background There has been an increased usage of metallic antimicrobial materials to control pathogenic and multi-drug resistant bacteria. Yet, there is a corresponding need to know if this usage leads to genetic adaptations that could produce more harmful strains. Methodology Experimental evolution was used to adapt Escherichia coli K-12 MG1655 to excess iron (II) with subsequent genomic analysis. Phenotypic assays and gene expression studies were conducted to demonstrate pleiotropic effects associated with this adaptation and to elucidate potential cellular responses. Results After 200 days of adaptation, populations cultured in excess iron (II), showed a significant increase in 24-h optical densities compared to controls. Furthermore, these populations showed increased resistance toward other metals [iron (III) and gallium (III)] and to traditional antibiotics (bacitracin, rifampin, chloramphenicol and sulfanilamide). Genomic analysis identified selective sweeps in three genes; fecA, ptsP and ilvG unique to the iron (II) resistant populations, and gene expression studies demonstrated that their cellular response may be to downregulate genes involved in iron transport (cirA and fecA) while increasing the oxidative stress response (oxyR, soxS and soxR) prior to FeSO4 exposure. Conclusions and implications Together, this indicates that the selected populations can quickly adapt to stressful levels of iron (II). This study is unique in that it demonstrates that E. coli can adapt to environments that contain excess levels of an essential micronutrient while also demonstrating the genomic foundations of the response and the pleiotropic consequences. The fact that adaptation to excess iron also causes increases in general antibiotic resistance is a serious concern. Lay summary: The evolution of iron resistance in E. coli leads to multi-drug and general metal resistance through the acquisition of mutations in three genes (fecA, ptsP and ilvG) while also initiating cellular defenses as part of their normal growth process.
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Affiliation(s)
- Misty D Thomas
- Department of Biology, North Carolina Agricultural and Technical State University, 1601 E. Market St, Greensboro, NC 27411, USA
| | - Akamu J Ewunkem
- BEACON, Center for the Study of Evolution in Action, Michigan State University, East Lansing, MI 48824, USA
| | - Sada Boyd
- Department of Nanoengineering, Joint School of Nanoscience and Nanoengineering, North Carolina Agricultural and Technical State University and UNC Greensboro, 2907 E. Gate City Blvd., Greensboro, NC 27401, USA
| | - Danielle K Williams
- Department of Biology, North Carolina Agricultural and Technical State University, 1601 E. Market St, Greensboro, NC 27411, USA
| | - Adiya Moore
- Department of Biology, North Carolina Agricultural and Technical State University, 1601 E. Market St, Greensboro, NC 27411, USA
| | - Kristen L Rhinehardt
- Computational Data Science and Engineering, North Carolina Agricultural and Technical State University, 1601 E. Market Street, Greensboro, NC 27411, USA
| | - Emma Van Beveren
- Department of Nanoengineering, Joint School of Nanoscience and Nanoengineering, North Carolina Agricultural and Technical State University and UNC Greensboro, 2907 E. Gate City Blvd., Greensboro, NC 27401, USA
| | - Bobi Yang
- Department of Nanoengineering, Joint School of Nanoscience and Nanoengineering, North Carolina Agricultural and Technical State University and UNC Greensboro, 2907 E. Gate City Blvd., Greensboro, NC 27401, USA
| | - Anna Tapia
- Department of Nanoengineering, Joint School of Nanoscience and Nanoengineering, North Carolina Agricultural and Technical State University and UNC Greensboro, 2907 E. Gate City Blvd., Greensboro, NC 27401, USA
| | - Jian Han
- Department of Biology, North Carolina Agricultural and Technical State University, 1601 E. Market St, Greensboro, NC 27411, USA
| | - Scott H Harrison
- Department of Biology, North Carolina Agricultural and Technical State University, 1601 E. Market St, Greensboro, NC 27411, USA
| | - Joseph L Graves
- Department of Biology, North Carolina Agricultural and Technical State University, 1601 E. Market St, Greensboro, NC 27411, USA
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Lucas JR, Alía A, Velasco R, Selgas MD, Cabeza MC. Effect of E-beam treatment on expression of virulence and stress-response genes of Listeria monocytogenes in dry-cured ham. Int J Food Microbiol 2021; 340:109057. [PMID: 33460999 DOI: 10.1016/j.ijfoodmicro.2021.109057] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 12/05/2020] [Accepted: 01/01/2021] [Indexed: 12/30/2022]
Abstract
Various adverse conditions can trigger defensive mechanisms in Listeria monocytogenes that can increase the virulence of surviving cells. The objective of this study was to evaluate the expression of one stress-response (sigB) and three virulence (plcA, hly, and iap) genes in L. monocytogenes exposed to a sub lethal dose of E-beam irradiation in dry-cured ham. To accomplish this, dry-cured ham slices (10 g) were immersed in a 109 CFU/mL suspension of L. monocytogenes strain S4-2 and subsequently irradiated with 1, 2, or 3 kGy. After irradiation, samples were stored at 7 °C or 15 °C for 30 days. Absolute gene expression levels were determined by RT-qPCR, and numbers of surviving Listeria cells were assessed by microbial counts after different storage times (0, 7, 15, and 30 days). At 7 °C, after E-beam treatment at doses of 2 or 3 kGy, Listeria gene expression significantly increased (p ≤ 0.05) up to day 15. Listeria counts decreased with increasing dosage. The relationship between absolute gene expression and the number of surviving Listeria cells could indicate that sublethal doses of E-beam irradiation can increase expression of the genes studied. We observed no significant influence of storage time or temperature on gene expression (p > 0.05). Listeria that survives E-beam treatment may display increased virulence, constituting a significant potential public health risk.
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Affiliation(s)
- J R Lucas
- Food Technology Dept. Section, Veterinary Faculty, Complutense University, Avd. Puerta de Hierro s/n, 28040 Madrid, Spain.
| | - A Alía
- Food Hygiene and Safety, Meat and Meat Products Research Institute, University of Extremadura, Avda. de la Universidad, s/n., 10003 Cáceres, Spain
| | - R Velasco
- Food Technology Dept. Section, Veterinary Faculty, Complutense University, Avd. Puerta de Hierro s/n, 28040 Madrid, Spain
| | - M D Selgas
- Food Technology Dept. Section, Veterinary Faculty, Complutense University, Avd. Puerta de Hierro s/n, 28040 Madrid, Spain
| | - M C Cabeza
- Food Technology Dept. Section, Veterinary Faculty, Complutense University, Avd. Puerta de Hierro s/n, 28040 Madrid, Spain
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Drlica K, Zhao X. Bacterial death from treatment with fluoroquinolones and other lethal stressors. Expert Rev Anti Infect Ther 2020; 19:601-618. [PMID: 33081547 DOI: 10.1080/14787210.2021.1840353] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
INTRODUCTION Lethal stressors, including antimicrobials, kill bacteria in part through a metabolic response proposed to involve reactive oxygen species (ROS). The quinolone anti-bacterials have served as key experimental tools in developing this idea. AREAS COVERED Bacteriostatic and bactericidal action of quinolones are distinguished, with emphasis on the contribution of chromosome fragmentation and ROS accumulation to bacterial death. Action of non-quinolone antibacterials and non-antimicrobial stressors is described to provide a general framework for understanding stress-mediated, bacterial death. EXPERT OPINION Quinolones trap topoisomerases on DNA in reversible complexes that block DNA replication and bacterial growth. At elevated drug concentrations, DNA ends are released from topoisomerase-mediated constraint, leading to the idea that death arises from chromosome fragmentation. However, DNA ends also stimulate repair, which is energetically expensive. An incompletely understood metabolic shift occurs, and ROS accumulate. Even after quinolone removal, ROS continue to amplify, generating secondary and tertiary damage that overwhelms repair and causes death. Repair may also contribute to death directly via DNA breaks arising from incomplete base-excision repair of ROS-oxidized nucleotides. Remarkably, perturbations that interfere with ROS accumulation confer tolerance to many diverse lethal agents.
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Affiliation(s)
| | - Xilin Zhao
- Rutgers University, Newark, NJ, USA.,State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, South Xiang-An Road, Xiang-An District, Xiamen, Fujian Province, China
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Khademian M, Imlay JA. Do reactive oxygen species or does oxygen itself confer obligate anaerobiosis? The case of Bacteroides thetaiotaomicron. Mol Microbiol 2020; 114:333-347. [PMID: 32301184 DOI: 10.1111/mmi.14516] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 04/07/2020] [Accepted: 04/07/2020] [Indexed: 02/06/2023]
Abstract
Bacteroides thetaiotaomicron was examined to determine whether its obligate anaerobiosis is imposed by endogenous reactive oxygen species or by molecular oxygen itself. Previous analyses established that aerated B. thetaiotaomicron loses some enzyme activities due to a high rate of endogenous superoxide formation. However, the present study establishes that another key step in central metabolism is poisoned by molecular oxygen itself. Pyruvate dissimilation was shown to depend upon two enzymes, pyruvate:formate lyase (PFL) and pyruvate:ferredoxin oxidoreductase (PFOR), that lose activity upon aeration. PFL is a glycyl-radical enzyme whose vulnerability to oxygen is already understood. The rate of PFOR damage was unaffected by the level of superoxide or peroxide, showing that molecular oxygen itself is the culprit. The cell cannot repair PFOR, which amplifies the impact of damage. The rates of PFOR and fumarase inactivation are similar, suggesting that superoxide dismutase is calibrated so the oxygen- and superoxide-sensitive enzymes are equally sensitive to aeration. The physiological purpose of PFL and PFOR is to degrade pyruvate without disrupting the redox balance, and they do so using catalytic mechanisms that are intrinsically vulnerable to oxygen. In this way, the anaerobic excellence and oxygen sensitivity of B. thetaiotaomicron are two sides of the same coin.
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Affiliation(s)
- Maryam Khademian
- Department of Microbiology, University of Illinois, Urbana, IL, USA
| | - James A Imlay
- Department of Microbiology, University of Illinois, Urbana, IL, USA
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Predictive Modeling of Microbial Behavior in Food. Foods 2019; 8:foods8120654. [PMID: 31817788 PMCID: PMC6963536 DOI: 10.3390/foods8120654] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 12/02/2019] [Accepted: 12/03/2019] [Indexed: 01/23/2023] Open
Abstract
Microorganisms can contaminate food, thus causing food spoilage and health risks when the food is consumed. Foods are not sterile; they have a natural flora and a transient flora reflecting their environment. To ensure food is safe, we must destroy these microorganisms or prevent their growth. Recurring hazards due to lapses in the handling, processing, and distribution of foods cannot be solved by obsolete methods and inadequate proposals. They require positive approach and resolution through the pooling of accumulated knowledge. As the industrial domain evolves rapidly and we are faced with pressures to continually improve both products and processes, a considerable competitive advantage can be gained by the introduction of predictive modeling in the food industry. Research and development capital concerns of the industry have been preserved by investigating the plethora of factors able to react on the final product. The presence of microorganisms in foods is critical for the quality of the food. However, microbial behavior is closely related to the properties of food itself such as water activity, pH, storage conditions, temperature, and relative humidity. The effect of these factors together contributing to permitting growth of microorganisms in foods can be predicted by mathematical modeling issued from quantitative studies on microbial populations. The use of predictive models permits us to evaluate shifts in microbial numbers in foods from harvesting to production, thus having a permanent and objective evaluation of the involving parameters. In this vein, predictive microbiology is the study of the microbial behavior in relation to certain environmental conditions, which assure food quality and safety. Microbial responses are evaluated through developed mathematical models, which must be validated for the specific case. As a result, predictive microbiology modeling is a useful tool to be applied for quantitative risk assessment. Herein, we review the predictive models that have been adapted for improvement of the food industry chain through a built virtual prototype of the final product or a process reflecting real-world conditions. It is then expected that predictive models are, nowadays, a useful and valuable tool in research as well as in industrial food conservation processes.
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Ślesak I, Kula M, Ślesak H, Miszalski Z, Strzałka K. How to define obligatory anaerobiosis? An evolutionary view on the antioxidant response system and the early stages of the evolution of life on Earth. Free Radic Biol Med 2019; 140:61-73. [PMID: 30862543 DOI: 10.1016/j.freeradbiomed.2019.03.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 03/01/2019] [Accepted: 03/05/2019] [Indexed: 10/27/2022]
Abstract
One of the former definitions of "obligate anaerobiosis" was based on three main criteria: 1) it occurs in organisms, so-called obligate anaerobes, which live in environments without oxygen (O2), 2) O2-dependent (aerobic) respiration, and 3) antioxidant enzymes are absent in obligate anaerobes. In contrast, aerobes need O2 in order to grow and develop properly. Obligate (or strict) anaerobes belong to prokaryotic microorganisms from two domains, Bacteria and Archaea. A closer look at anaerobiosis covers a wide range of microorganisms that permanently or in a time-dependent manner tolerate different concentrations of O2 in their habitats. On this basis they can be classified as obligate/facultative anaerobes, microaerophiles and nanaerobes. Paradoxically, O2 tolerance in strict anaerobes is usually, as in aerobes, associated with the activity of the antioxidant response system, which involves different antioxidant enzymes responsible for removing excess reactive oxygen species (ROS). In our opinion, the traditional definition of "obligate anaerobiosis" loses its original sense. Strict anaerobiosis should only be restricted to the occurrence of O2-independent pathways involved in energy generation. For that reason, a term better than "obligate anaerobes" would be O2/ROS tolerant anaerobes, where the role of the O2/ROS detoxification system is separated from O2-independent metabolic pathways that supply energy. Ubiquitous key antioxidant enzymes like superoxide dismutase (SOD) and superoxide reductase (SOR) in contemporary obligate anaerobes might suggest that their origin is ancient, maybe even the beginning of the evolution of life on Earth. It cannot be ruled out that c. 3.5 Gyr ago, local microquantities of O2/ROS played a role in the evolution of the last universal common ancestor (LUCA) of all modern organisms. On the basis of data in the literature, the hypothesis that LUCA could be an O2/ROS tolerant anaerobe is discussed together with the question of the abiotic sources of O2/ROS and/or the early evolution of cyanobacteria that perform oxygenic photosynthesis.
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Affiliation(s)
- Ireneusz Ślesak
- The Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, Niezapominajek 21, 30-239, Krakow, Poland.
| | - Monika Kula
- The Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, Niezapominajek 21, 30-239, Krakow, Poland.
| | - Halina Ślesak
- Institute of Botany, Jagiellonian University, Gronostajowa 9, 30-387, Krakow, Poland.
| | - Zbigniew Miszalski
- The Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, Niezapominajek 21, 30-239, Krakow, Poland.
| | - Kazimierz Strzałka
- Malopolska Centre of Biotechnology, Jagiellonian University, Gronostajowa 7A, 30-387, Krakow, Poland; Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387, Krakow, Poland.
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Bewick S, Gurarie E, Weissman JL, Beattie J, Davati C, Flint R, Thielen P, Breitwieser F, Karig D, Fagan WF. Trait-based analysis of the human skin microbiome. MICROBIOME 2019; 7:101. [PMID: 31277701 PMCID: PMC6612184 DOI: 10.1186/s40168-019-0698-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 05/19/2019] [Indexed: 05/04/2023]
Abstract
BACKGROUND The past decade of microbiome research has concentrated on cataloging the diversity of taxa in different environments. The next decade is poised to focus on microbial traits and function. Most existing methods for doing this perform pathway analysis using reference databases. This has both benefits and drawbacks. Function can go undetected if reference databases are coarse-grained or incomplete. Likewise, detection of a pathway does not guarantee expression of the associated function. Finally, function cannot be connected to specific microbial constituents, making it difficult to ascertain the types of organisms exhibiting particular traits-something that is important for understanding microbial success in specific environments. A complementary approach to pathway analysis is to use the wealth of microbial trait information collected over years of lab-based, culture experiments. METHODS Here, we use journal articles and Bergey's Manual of Systematic Bacteriology to develop a trait-based database for 971 human skin bacterial taxa. We then use this database to examine functional traits that are over/underrepresented among skin taxa. Specifically, we focus on three trait classes-binary, categorical, and quantitative-and compare trait values among skin taxa and microbial taxa more broadly. We compare binary traits using a Chi-square test, categorical traits using randomization trials, and quantitative traits using a nonparametric relative effects test based on global rankings using Tukey contrasts. RESULTS We find a number of traits that are over/underrepresented within the human skin microbiome. For example, spore formation, acid phosphatase, alkaline phosphatase, pigment production, catalase, and oxidase are all less common among skin taxa. As well, skin bacteria are less likely to be aerobic, favoring, instead, a facultative strategy. They are also less likely to exhibit gliding motility, less likely to be spirillum or rod-shaped, and less likely to grow in chains. Finally, skin bacteria have more difficulty at high pH, prefer warmer temperatures, and are much less resilient to hypotonic conditions. CONCLUSIONS Our analysis shows how an approach that relies on information from culture experiments can both support findings from pathway analysis, and also generate new insights into the structuring principles of microbial communities.
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Affiliation(s)
- Sharon Bewick
- Department of Biological Sciences, Clemson University, Clemson, SC 29631 USA
| | - Eliezer Gurarie
- Department of Biology, University of Maryland, College Park, MD 20742 USA
| | - JL Weissman
- Department of Biology, University of Maryland, College Park, MD 20742 USA
| | - Jess Beattie
- Department of Biology, University of Maryland, College Park, MD 20742 USA
| | - Cyrus Davati
- Department of Biology, University of Maryland, College Park, MD 20742 USA
| | - Rachel Flint
- Department of Biology, University of Maryland, College Park, MD 20742 USA
| | - Peter Thielen
- Research and Exploratory Development Department, Johns Hopkins Applied Physics Laboratory, Laurel, MD 20723 USA
| | - Florian Breitwieser
- Center for Computational Biology, McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins School of Medicine, Baltimore, MD 21205 USA
| | - David Karig
- Research and Exploratory Development Department, Johns Hopkins Applied Physics Laboratory, Laurel, MD 20723 USA
- Department of Bioengineering, Clemson University, Clemson, SC 29631 USA
| | - William F. Fagan
- Department of Biology, University of Maryland, College Park, MD 20742 USA
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Timing the Evolutionary Advent of Cyanobacteria and the Later Great Oxidation Event Using Gene Phylogenies of a Sunscreen. mBio 2019; 10:mBio.00561-19. [PMID: 31113897 PMCID: PMC6529634 DOI: 10.1128/mbio.00561-19] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The biosynthesis of the unique cyanobacterial (oxyphotobacterial) indole-phenolic UVA sunscreen, scytonemin, is coded for in a conserved operon that contains both core metabolic genes and accessory, aromatic amino acid biosynthesis genes dedicated to supplying scytonemin's precursors. Comparative genomics shows conservation of this operon in many, but not all, cyanobacterial lineages. Phylogenetic analyses of the operon's aromatic amino acid genes indicate that five of them were recruited into the operon after duplication events of their respective housekeeping cyanobacterial cognates. We combined the fossil record of cyanobacteria and relaxed molecular clock models to obtain multiple estimates of these duplication events, setting a minimum age for the evolutionary advent of scytonemin at 2.1 ± 0.3 billion years. The same analyses were used to estimate the advent of cyanobacteria as a group (and thus the appearance of oxygenic photosynthesis), at 3.6 ± 0.2 billion years before present. Post hoc interpretation of 16S rRNA-based Bayesian analyses was consistent with these estimates. Because of physiological constraints on the use of UVA sunscreens in general, and the biochemical constraints of scytonemin in particular, scytonemin's age must postdate the time when Earth's atmosphere turned oxic, known as the Great Oxidation Event (GOE). Indeed, our biological estimate is in agreement with independent geochemical estimates for the GOE. The difference between the estimated ages of oxygenic photosynthesis and the GOE indicates the long span (on the order of a billion years) of the era of "oxygen oases," when oxygen was available locally but not globally.IMPORTANCE The advent of cyanobacteria, with their invention of oxygenic photosynthesis, and the Great Oxidation Event are arguably among the most important events in the evolutionary history of life on Earth. Oxygen is a significant toxicant to all life, but its accumulation in the atmosphere also enabled the successful development and proliferation of many aerobic organisms, especially metazoans. The currently favored dating of the Great Oxidation Event is based on the geochemical rock record. Similarly, the advent of cyanobacteria is also often drawn from the same estimates because in older rocks paleontological evidence is scarce or has been discredited. Efforts to obtain molecular evolutionary alternatives have offered widely divergent estimates. Our analyses provide a novel means to circumvent these limitations and allow us to estimate the large time gap between the two events.
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Lee SH, Youn H, Kang SG, Lee HS. Oxygen-mediated growth enhancement of an obligate anaerobic archaeon Thermococcus onnurineus NA1. J Microbiol 2019; 57:138-142. [PMID: 30706342 DOI: 10.1007/s12275-019-8592-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 11/13/2018] [Accepted: 11/21/2018] [Indexed: 11/27/2022]
Abstract
Thermococcus onnurineus NA1, an obligate anaerobic hyperthermophilic archaeon, showed variable oxygen (O2) sensitivity depending on the types of substrate employed as an energy source. Unexpectedly, the culture with yeast extract as a sole energy source showed enhanced growth by 2-fold in the presence of O2. Genome-wide transcriptome analysis revealed the upregulation of several antioxidant-related genes encoding thioredoxin peroxidase (TON_0862), rubrerythrin (TON_0864), rubrerythrin-related protein (TON_0873), NAD(P)H rubredoxin oxidoreductase (TON_0865), or thioredoxin reductase (TON_1603), which can couple the detoxification of reactive oxygen species with the regeneration of NAD(P)+ from NAD(P)H. We present a plausible mechanism by which O2 serves to maintain the intracellular redox balance. This study demonstrates an unusual strategy of an obligate anaerobe underlying O2-mediated growth enhancement despite not having heme-based or cytochrome-type proteins.
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Affiliation(s)
- Seong Hyuk Lee
- Korea Institute of Ocean Science and Technology, Busan, 49111, Republic of Korea
| | - Hwan Youn
- Department of Biology, California State University, Fresno, CA, 93740-8034, USA
| | - Sung Gyun Kang
- Korea Institute of Ocean Science and Technology, Busan, 49111, Republic of Korea.
- Department of Marine Biotechnology, Korea University of Science and Technology, Daejeon, 34113, Republic of Korea.
| | - Hyun Sook Lee
- Korea Institute of Ocean Science and Technology, Busan, 49111, Republic of Korea.
- Department of Marine Biotechnology, Korea University of Science and Technology, Daejeon, 34113, Republic of Korea.
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Martin HA, Porter KE, Vallin C, Ermi T, Contreras N, Pedraza-Reyes M, Robleto EA. Mfd protects against oxidative stress in Bacillus subtilis independently of its canonical function in DNA repair. BMC Microbiol 2019; 19:26. [PMID: 30691388 PMCID: PMC6350366 DOI: 10.1186/s12866-019-1394-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 01/16/2019] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Previous reports showed that mutagenesis in nutrient-limiting conditions is dependent on Mfd in Bacillus subtilis. Mfd initiates one type of transcription-coupled repair (TCR); this type of repair is known to target bulky lesions, like those associated with UV exposure. Interestingly, the roles of Mfd in repair of oxidative-promoted DNA damage and regulation of transcription differ. Here, we used a genetic approach to test whether Mfd protected B. subtilis from exposure to two different oxidants. RESULTS Wild-type cells survived tert-butyl hydroperoxide (t-BHP) exposure significantly better than Mfd-deficient cells. This protective effect was independent of UvrA, a component of the canonical TCR/nucleotide excision repair (NER) pathway. Further, our results suggest that Mfd and MutY, a DNA glycosylase that processes 8-oxoG DNA mismatches, work together to protect cells from lesions generated by oxidative damage. We also tested the role of Mfd in mutagenesis in starved cells exposed to t-BHP. In conditions of oxidative stress, Mfd and MutY may work together in the formation of mutations. Unexpectedly, Mfd increased survival when cells were exposed to the protein oxidant diamide. Under this type of oxidative stress, cells survival was not affected by MutY or UvrA. CONCLUSIONS These results are significant because they show that Mfd mediates error-prone repair of DNA and protects cells against oxidation of proteins by affecting gene expression; Mfd deficiency resulted in increased gene expression of the OhrR repressor which controls the cellular response to organic peroxide exposure. These observations point to Mfd functioning beyond a DNA repair factor in cells experiencing oxidative stress.
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Affiliation(s)
- Holly Anne Martin
- School of Life Sciences, University of Nevada, Las Vegas, 4505 Maryland Parkway, Las Vegas, Nevada, 89154, USA
| | - Katelyn E Porter
- School of Life Sciences, University of Nevada, Las Vegas, 4505 Maryland Parkway, Las Vegas, Nevada, 89154, USA
| | - Carmen Vallin
- School of Life Sciences, University of Nevada, Las Vegas, 4505 Maryland Parkway, Las Vegas, Nevada, 89154, USA
| | - Tatiana Ermi
- School of Life Sciences, University of Nevada, Las Vegas, 4505 Maryland Parkway, Las Vegas, Nevada, 89154, USA
| | - Natalie Contreras
- School of Life Sciences, University of Nevada, Las Vegas, 4505 Maryland Parkway, Las Vegas, Nevada, 89154, USA
| | - Mario Pedraza-Reyes
- Department of Biology, Division of Natural and Exact Sciences, University of Guanajuato, P.O. Box 187, Gto. 36050, Guanajuato, Mexico
| | - Eduardo A Robleto
- School of Life Sciences, University of Nevada, Las Vegas, 4505 Maryland Parkway, Las Vegas, Nevada, 89154, USA.
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Guerrero-Cruz S, Cremers G, van Alen TA, Op den Camp HJM, Jetten MSM, Rasigraf O, Vaksmaa A. Response of the Anaerobic Methanotroph " Candidatus Methanoperedens nitroreducens" to Oxygen Stress. Appl Environ Microbiol 2018; 84:e01832-18. [PMID: 30291120 PMCID: PMC6275348 DOI: 10.1128/aem.01832-18] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Accepted: 10/01/2018] [Indexed: 11/20/2022] Open
Abstract
"Candidatus Methanoperedens nitroreducens" is an archaeon that couples the anaerobic oxidation of methane to nitrate reduction. In natural and man-made ecosystems, this archaeon is often found at oxic-anoxic interfaces where nitrate, the product of aerobic nitrification, cooccurs with methane produced by methanogens. As such, populations of "Ca Methanoperedens nitroreducens" could be prone to regular oxygen exposure. Here, we investigated the effect of 5% (vol/vol) oxygen exposure in batch activity assays on a "Ca Methanoperedens nitroreducens" culture, enriched from an Italian paddy field. Metagenome sequencing of the DNA extracted from the enrichment culture revealed that 83% of 16S rRNA gene reads were assigned to a novel strain, "Candidatus Methanoperedens nitroreducens Verserenetto." RNA was extracted, and metatranscriptome sequencing upon oxygen exposure revealed that the active community changed, most notably in the appearance of aerobic methanotrophs. The gene expression of "Ca Methanoperedens nitroreducens" revealed that the key genes encoding enzymes of the methane oxidation and nitrate reduction pathways were downregulated. In contrast to this, we identified upregulation of glutaredoxin, thioredoxin family/like proteins, rubrerythrins, peroxiredoxins, peroxidase, alkyl hydroperoxidase, type A flavoproteins, FeS cluster assembly protein, and cysteine desulfurases, indicating the genomic potential of "Ca Methanoperedens nitroreducens Verserenetto" to counteract the oxidative damage and adapt in environments where they might be exposed to regular oxygen intrusion.IMPORTANCE "Candidatus Methanoperedens nitroreducens" is an anaerobic archaeon which couples the reduction of nitrate to the oxidation of methane. This microorganism is present in a wide range of aquatic environments and man-made ecosystems, such as paddy fields and wastewater treatment systems. In such environments, these archaea may experience regular oxygen exposure. However, "Ca Methanoperedens nitroreducens" is able to thrive under such conditions and could be applied for the simultaneous removal of dissolved methane and nitrogenous pollutants in oxygen-limited systems. To understand what machinery "Ca Methanoperedens nitroreducens" possesses to counteract the oxidative stress and survive, we characterized the response to oxygen exposure using a multi-omics approach.
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Affiliation(s)
- Simon Guerrero-Cruz
- Department of Microbiology, IWWR, Radboud University Nijmegen, Nijmegen, the Netherlands
| | - Geert Cremers
- Department of Microbiology, IWWR, Radboud University Nijmegen, Nijmegen, the Netherlands
| | - Theo A van Alen
- Department of Microbiology, IWWR, Radboud University Nijmegen, Nijmegen, the Netherlands
| | - Huub J M Op den Camp
- Department of Microbiology, IWWR, Radboud University Nijmegen, Nijmegen, the Netherlands
| | - Mike S M Jetten
- Department of Microbiology, IWWR, Radboud University Nijmegen, Nijmegen, the Netherlands
- Department of Biotechnology, Delft University of Technology, Delft, the Netherlands
- Soehngen Institute of Anaerobic Microbiology, Nijmegen, the Netherlands
| | - Olivia Rasigraf
- Department of Microbiology, IWWR, Radboud University Nijmegen, Nijmegen, the Netherlands
| | - Annika Vaksmaa
- Department of Microbiology, IWWR, Radboud University Nijmegen, Nijmegen, the Netherlands
- Royal Netherlands Institute for Sea Research, Texel, the Netherlands
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Yan M, Wang BH, Xu X, der Meister T, Tabγač HT, Hwang FF, Liu Z. Extrusion of Dissolved Oxygen by Exopolysaccharide From Leuconostoc mesenteroides and Its Implications in Relief of the Oxygen Stress. Front Microbiol 2018; 9:2467. [PMID: 30405549 PMCID: PMC6202936 DOI: 10.3389/fmicb.2018.02467] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 09/26/2018] [Indexed: 01/12/2023] Open
Abstract
Strains of Leuconostoc are generally facultatively anaerobic and exposure to oxygen might be detrimental; therefore, strategies to combat the oxygen stress are essential for these bacteria to survive and flourish in the oxygenic atmosphere. Despite the extensive applications in industry, the fundamental issues concerning the aerobic life of Leuconostocs remain to be addressed. In this study, we have demonstrated that Leuconostoc mesenteroides CGMCC10064 cultivated in sucrose medium would acquire a growth advantage over that in glucose medium under oxygenic conditions, as reflected by more viable cells and less accumulation of reactive oxygen species. Further analysis showed that the growth advantage was dependent on exopolysaccharide (EPS) synthesized by a secreted glucansucrase. Determination of the dissolved oxygen in the culture suggested that the growth improvement was mediated by extrusion of dissolved oxygen from the aqueous circumstances. Growth experiments performed with the purified EPS showed that supplementation of 5 g/L EPS in the medium could improve the aerobic growth of L. mesenteroides by ∼10-fold. Moreover, the purified EPS was also effective in promoting the aerobic growth of oxygen-sensitive Lactobacillus and Bifidobacterium. These results demonstrate that EPS of L. mesenteroides plays a critical role in relief of the oxygen stress, and suggest the potential of the EPS in manufacture as well as preservation of oxygen-sensitive probiotics.
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Affiliation(s)
- Minghui Yan
- State Key Laboratory of Dairy Biotechnology, Shanghai Engineering Research Center of Dairy Biotechnology, Dairy Research Institute, Bright Dairy & Food Co., Ltd., Shanghai, China
| | - Bing-hua Wang
- The Department of Clinical Laboratory, Central Laboratory, Jing’an District Center Hospital of Shanghai, Fudan University, Shanghai, China
| | - Xiaofen Xu
- State Key Laboratory of Dairy Biotechnology, Shanghai Engineering Research Center of Dairy Biotechnology, Dairy Research Institute, Bright Dairy & Food Co., Ltd., Shanghai, China
| | - Tsiba der Meister
- Diagnosis Laboratory, Institut Louis Malardé, Papeete, French Polynesia
- Department of Internal Medicine, French Polynesia Hospital Center, Pirae, French Polynesia
| | - Hei-tsai Tabγač
- Diagnosis Laboratory, Institut Louis Malardé, Papeete, French Polynesia
| | - Fat-fat Hwang
- Diagnosis Laboratory, Institut Louis Malardé, Papeete, French Polynesia
| | - Zhenmin Liu
- State Key Laboratory of Dairy Biotechnology, Shanghai Engineering Research Center of Dairy Biotechnology, Dairy Research Institute, Bright Dairy & Food Co., Ltd., Shanghai, China
- Synergetic Innovation Center for Food Safety and Nutrition, Jiangnan University, Wuxi, China
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44
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Barth C, Weiss MC, Roettger M, Martin WF, Unden G. Origin and phylogenetic relationships of [4Fe-4S]-containing O 2 sensors of bacteria. Environ Microbiol 2018; 20:4567-4586. [PMID: 30225854 DOI: 10.1111/1462-2920.14411] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Accepted: 09/10/2018] [Indexed: 11/28/2022]
Abstract
The advent of environmental O2 about 2.5 billion years ago forced microbes to metabolically adapt and to develop mechanisms for O2 sensing. Sensing of O2 by [4Fe-4S]2+ to [2Fe-2S]2+ cluster conversion represents an ancient mechanism that is used by FNREc (Escherichia coli), FNRBs (Bacillus subtilis), NreBSa (Staphylococcus aureus) and WhiB3Mt (Mycobacterium tuberculosis). The phylogenetic relationship of these sensors was investigated. FNREc homologues are restricted to the proteobacteria and a few representatives from other phyla. Homologues of FNRBs and NreBSa are located within the bacilli, of WhiB3 within the actinobacteria. Archaea contain no homologues. The data reveal no similarity between the FNREc , FNRBs , NreBSa and WhiB3 sensor families on the sequence and structural levels. These O2 sensor families arose independently in phyla that were already present at the time O2 appeared, their members were subsequently distributed by lateral gene transfer. The chemistry of [4Fe-4S] and [2Fe-2S] cluster formation and interconversion appears to be shared by the sensor protein families. The type of signal output is, however, family specific. The homologues of FNREc and NreBSa vary with regard to the number of Cys residues that coordinate the cluster. It is suggested that the variants derive from lateral gene transfer and gained other functions.
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Affiliation(s)
- C Barth
- Microbiology and Wine Research, Institute for Molecular Physiology, Johannes Gutenberg University Mainz, Mainz, Germany
| | - M C Weiss
- Institute for Molecular Evolution, Heinrich Heine University of Düsseldorf, Düsseldorf, Germany
| | - M Roettger
- Institute for Molecular Evolution, Heinrich Heine University of Düsseldorf, Düsseldorf, Germany
| | - W F Martin
- Institute for Molecular Evolution, Heinrich Heine University of Düsseldorf, Düsseldorf, Germany
| | - G Unden
- Microbiology and Wine Research, Institute for Molecular Physiology, Johannes Gutenberg University Mainz, Mainz, Germany
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45
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Blahut M, Dzul S, Wang S, Kandegedara A, Grossoehme NE, Stemmler T, Outten FW. Conserved cysteine residues are necessary for nickel-induced allosteric regulation of the metalloregulatory protein YqjI (NfeR) in E. coli. J Inorg Biochem 2018; 184:123-133. [PMID: 29723740 DOI: 10.1016/j.jinorgbio.2018.04.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2017] [Revised: 04/19/2018] [Accepted: 04/22/2018] [Indexed: 11/28/2022]
Abstract
Transition metal homeostasis is necessary to sustain life. First row transition metals act as cofactors within the cell, performing vital functions ranging from DNA repair to respiration. However, intracellular metal concentrations exceeding physiological requirements may be toxic. In E. coli, the YqjH flavoprotein is thought to play a role in iron homeostasis. YqjH is transcriptionally regulated by the ferric uptake regulator and a newly discovered regulator encoded by yqjI. The apo-form of YqjI is a transcriptional repressor of both the yqjH and yqjI genes. YqjI repressor function is disrupted upon binding of nickel. The YqjI N-terminus is homologous to nickel-binding proteins, implicating this region as a nickel-binding domain. Based on function, yqjI and yqjH should be renamed Ni-responsive Fe-uptake regulator (nfeR) and Ni-responsive Fe-uptake flavoprotein (nfeF), respectively. X-ray Absorption Spectroscopy was employed to characterize the nickel binding site(s) within YqjI. Putative nickel binding ligands were targeted by site-directed mutagenesis and resulting variants were analyzed in vivo for repressor function. Isothermal titration calorimetry and competitive binding assays were used to further quantify nickel interactions with wild-type YqjI and its mutant derivatives. Results indicate plasticity in the nickel binding domain of YqjI. Residues C42 and C43 were found to be required for in vivo response of YqjI to nickel stress, though these residues are not required for in vitro nickel binding. We propose that YqjI may contain a vicinal disulfide bond between C42 and C43 that is important for nickel-responsive allosteric interactions between YqjI domains.
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Affiliation(s)
- Matthew Blahut
- University of South Carolina, Department of Chemistry and Biochemistry, Columbia, SC 29208, USA
| | - Stephen Dzul
- Wayne State University, Department of Pharmaceutical Sciences, Detroit, MI 48201, USA
| | - Suning Wang
- University of South Carolina, Department of Chemistry and Biochemistry, Columbia, SC 29208, USA
| | - Ashoka Kandegedara
- Wayne State University, Department of Pharmaceutical Sciences, Detroit, MI 48201, USA
| | - Nicholas E Grossoehme
- Winthrop University, Department of Chemistry, Physics, and Geology, Rock Hill, SC 29733, USA
| | - Timothy Stemmler
- Wayne State University, Department of Pharmaceutical Sciences, Detroit, MI 48201, USA
| | - F Wayne Outten
- University of South Carolina, Department of Chemistry and Biochemistry, Columbia, SC 29208, USA.
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46
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Clostridial Strain-Specific Characteristics Associated with Necrotizing Enterocolitis. Appl Environ Microbiol 2018; 84:AEM.02428-17. [PMID: 29352082 DOI: 10.1128/aem.02428-17] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 01/11/2018] [Indexed: 12/21/2022] Open
Abstract
We aimed at identifying potential bacterial factors linking clostridia with necrotizing enterocolitis (NEC). We compared the phenotypic traits, stress responses, cellular cytotoxicity, and inflammatory capabilities of the largest collection of Clostridium butyricum and Clostridium neonatale strains isolated from fecal samples of NEC preterm neonates (PN) and control PNs. When strain characteristics were used as explanatory variables, a statistical discriminant analysis allowed the separation of NEC and control strains into separate groups. Strains isolated from NEC PN were characterized by a higher viability at 30°C (P = 0.03) and higher aerotolerance (P = 0.01), suggesting that NEC strains may have a competitive and/or survival advantage in the environmental gastrointestinal tract conditions of NEC PN. Heat-treated NEC bacteria induced higher production of interleukin-8 in Caco-2 cells (P = 0.03), suggesting proinflammatory activity. In vitro, bacteria, bacterial components, and fecal filtrates showed variable cytotoxic effects affecting the cellular network and/or cell viability, without specific association with NEC or control samples. Altogether, our data support the existence of a specific clostridial strain signature associated with NEC.IMPORTANCE Clostridia are part of the commensal microbiota in preterm neonates (PN). However, microbiota analyses by culture and metagenomics have linked necrotizing enterocolitis (NEC) and intestinal colonization with clostridial species. Nevertheless, little is known about the specific characteristics that may be shared by clostridia associated with NEC compared to commensal clostridia. Therefore, our goal was to identify specific bacterial factors linking clostridial strains with NEC. We report the existence of a specific bacterial signature associated with NEC and propose that activation of the innate immune response may be a unifying causative mechanism for the development of NEC independent of a specific pathogenic organism. The present study provides new insights into NEC pathophysiology that are needed for better diagnostics and strategies for implementing prevention of the disease.
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47
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Novel Sequence Features of DNA Repair Genes/Proteins from Deinococcus Species Implicated in Protection from Oxidatively Generated Damage. Genes (Basel) 2018. [PMID: 29518000 PMCID: PMC5867870 DOI: 10.3390/genes9030149] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Deinococcus species display a high degree of resistance to radiation and desiccation due to their ability to protect critical proteome from oxidatively generated damage; however, the underlying mechanisms are not understood. Comparative analysis of DNA repair proteins reported here has identified 22 conserved signature indels (CSIs) in the proteins UvrA1, UvrC, UvrD, UvsE, MutY, MutM, Nth, RecA, RecD, RecG, RecQ, RecR, RuvC, RadA, PolA, DnaE, LigA, GyrA and GyrB, that are uniquely shared by all/most Deinococcus homologs. Of these CSIs, a 30 amino acid surface-exposed insert in the Deinococcus UvrA1, which distinguishes it from all other UvrA homologs, is of much interest. The uvrA1 gene in Deinococcus also exhibits specific genetic linkage (predicted operonic arrangement) to genes for three other proteins including a novel Deinococcus-specific transmembrane protein (designated dCSP-1) and the proteins DsbA and DsbB, playing central roles in protein disulfide bond formation by oxidation-reduction of CXXC (C represents cysteine, X any other amino acid) motifs. The CXXC motifs provide important targets for oxidation damage and they are present in many DNA repair proteins including five in UvrA, which are part of Zinc-finger elements. A conserved insert specific for Deinococcus is also present in the DsbA protein. Additionally, the uvsE gene in Deinococcus also shows specific linkage to the gene for a membrane-associated protein. To account for these novel observations, a model is proposed where specific interaction of the Deinococcus UvrA1 protein with membrane-bound dCSP-1 enables the UvrA1 to receive electrons from DsbA-DsbB oxido-reductase machinery to ameliorate oxidation damage in the UvrA1 protein.
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48
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Reyes AM, Pedre B, De Armas MI, Tossounian MA, Radi R, Messens J, Trujillo M. Chemistry and Redox Biology of Mycothiol. Antioxid Redox Signal 2018; 28:487-504. [PMID: 28372502 DOI: 10.1089/ars.2017.7074] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
SIGNIFICANCE Mycothiol (MSH, AcCys-GlcN-Ins) is the main low-molecular weight (LMW) thiol of most Actinomycetes, including the human pathogen Mycobacterium tuberculosis that affects millions of people worldwide. Strains with decreased MSH content show increased susceptibilities to hydroperoxides and electrophilic compounds. In M. tuberculosis, MSH modulates the response to several antituberculosis drugs. Enzymatic routes involving MSH could provide clues for specific drug design. Recent Advances: Physicochemical data argue against a rapid, nonenzymatic reaction of MSH with oxidants, disulfides, or electrophiles. Moreover, exposure of the bacteria to high concentrations of two-electron oxidants resulted in protein mycothiolation. The recently described glutaredoxin-like protein mycoredoxin-1 (Mrx-1) provides a route for catalytic reduction of mycothiolated proteins, protecting critical cysteines from irreversible oxidation. The description of MSH/Mrx-1-dependent activities of peroxidases helped to explain the higher susceptibility to oxidants observed in Actinomycetes lacking MSH. Moreover, the first mycothiol-S-transferase, member of the DinB superfamily of proteins, was described. In Corynebacterium, both the MSH/Mrx-1 and the thioredoxin pathways reduce methionine sulfoxide reductase A. A novel tool for in vivo imaging of the MSH/mycothiol disulfide (MSSM) status allows following changes in the mycothiol redox state during macrophage infection and its relationship with antibiotic sensitivity. CRITICAL ISSUES Redundancy of MSH with other LMW thiols is starting to be unraveled and could help to rationalize the differences in the reported importance of MSH synthesis observed in vitro versus in animal infection models. FUTURE DIRECTIONS Future work should be directed to establish the structural bases of the specificity of MSH-dependent enzymes, thus facilitating drug developments. Antioxid. Redox Signal. 28, 487-504.
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Affiliation(s)
- Aníbal M Reyes
- 1 Departamento de Bioquímica, Facultad de Medicina, Universidad de la República , Montevideo, Uruguay .,2 Center for Free Radical and Biomedical Research , Universidad de la República, Montevideo, Uruguay
| | - Brandán Pedre
- 3 Center for Structural Biology , VIB, Brussels, Belgium .,4 Brussels Center for Redox Biology , Brussels, Belgium .,5 Structural Biology Brussels, Vrije Universiteit Brussel , Brussels, Belgium
| | - María Inés De Armas
- 1 Departamento de Bioquímica, Facultad de Medicina, Universidad de la República , Montevideo, Uruguay .,2 Center for Free Radical and Biomedical Research , Universidad de la República, Montevideo, Uruguay
| | - Maria-Armineh Tossounian
- 3 Center for Structural Biology , VIB, Brussels, Belgium .,4 Brussels Center for Redox Biology , Brussels, Belgium .,5 Structural Biology Brussels, Vrije Universiteit Brussel , Brussels, Belgium
| | - Rafael Radi
- 1 Departamento de Bioquímica, Facultad de Medicina, Universidad de la República , Montevideo, Uruguay .,2 Center for Free Radical and Biomedical Research , Universidad de la República, Montevideo, Uruguay
| | - Joris Messens
- 3 Center for Structural Biology , VIB, Brussels, Belgium .,4 Brussels Center for Redox Biology , Brussels, Belgium .,5 Structural Biology Brussels, Vrije Universiteit Brussel , Brussels, Belgium
| | - Madia Trujillo
- 1 Departamento de Bioquímica, Facultad de Medicina, Universidad de la República , Montevideo, Uruguay .,2 Center for Free Radical and Biomedical Research , Universidad de la República, Montevideo, Uruguay
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Guilhot E, Khelaifia S, La Scola B, Raoult D, Dubourg G. Methods for culturing anaerobes from human specimen. Future Microbiol 2018; 13:369-381. [PMID: 29446650 DOI: 10.2217/fmb-2017-0170] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Anaerobes represent the dominating population in the human gut microbiota and play a key role in gut homeostasis. In addition, several anaerobes are now considered as probiotics and they remain essential to several processes in the field of biotechnology. With the implementation of MALDI-TOF MS in routine laboratories, anaerobes are no longer neglected in clinical microbiology, as their identification is made easy. However, the isolation and identification of anaerobic bacteria, remains time consuming, fastidious and costly. Various strategies have been developed, from sampling to culturing human specimens, which will be discussed in this paper. Also, particular attention is paid to isolating species with special medical importance, as for contribution to the field of culturomics.
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Affiliation(s)
- Elodie Guilhot
- Aix Marseille Univ., IRD, AP-HM, MEPHI, IHU Méditerranée Infection, Marseille, France
| | - Saber Khelaifia
- Aix Marseille Univ., IRD, AP-HM, MEPHI, IHU Méditerranée Infection, Marseille, France
| | - Bernard La Scola
- Aix Marseille Univ., IRD, AP-HM, MEPHI, IHU Méditerranée Infection, Marseille, France
| | - Didier Raoult
- Aix Marseille Univ., IRD, AP-HM, MEPHI, IHU Méditerranée Infection, Marseille, France
| | - Grégory Dubourg
- Aix Marseille Univ., IRD, AP-HM, MEPHI, IHU Méditerranée Infection, Marseille, France
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50
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Lyu Z, Lu Y. Metabolic shift at the class level sheds light on adaptation of methanogens to oxidative environments. ISME JOURNAL 2017; 12:411-423. [PMID: 29135970 PMCID: PMC5776455 DOI: 10.1038/ismej.2017.173] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Revised: 07/31/2017] [Accepted: 08/09/2017] [Indexed: 11/09/2022]
Abstract
Methanogens have long been considered strictly anaerobic and oxygen-sensitive microorganisms, but their ability to survive oxygen stress has also been documented. Indeed, methanogens have been found in oxidative environments, and antioxidant genes have been detected in their genomes. How methanogens adapt to oxidative environments, however, remain poorly understood. Here, we systematically predicted and annotated antioxidant features from representative genomes across six well-established methanogen orders. Based on functional gene content involved in production of reactive oxygen species, Hierarchical Clustering analyses grouped methanogens into two distinct clusters, corresponding to the Class I and II methanogens, respectively. Comparative genomics suggested a systematic shift in metabolisms across the two classes, resulting in an enrichment of antioxidant features in the Class II. Moreover, meta-analysis of 16 S rRNA gene sequences obtained from EnvDB indicated that members of Class II were more frequently recovered from microaerophilic and even oxic environments than the Class I members. Phylogenomic analysis suggested that the Class I and II methanogens might have evolved before and around the Great Oxygenation Event, respectively. The enrichment of antioxidant features in the Class II methanogens may have played a key role in the adaption of this group to oxidative environments today and historically.
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Affiliation(s)
- Zhe Lyu
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, PR China.,Department of Microbiology, University of Georgia, Athens, GA, USA
| | - Yahai Lu
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, PR China.,College of Urban and Environmental Sciences, Peking University, Beijing, PR China
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