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Singh B, Jaiswal S, Kodgire P. Outer membrane proteins and vesicles as promising vaccine candidates against Vibrio spp. infections. Crit Rev Microbiol 2024; 50:417-433. [PMID: 37272649 DOI: 10.1080/1040841x.2023.2212072] [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: 10/19/2022] [Revised: 02/12/2023] [Accepted: 05/02/2023] [Indexed: 06/06/2023]
Abstract
Indiscriminate use of antibiotics to treat bacterial infections has brought unmanageable antibiotic-resistant strains into existence. Vibrio spp. represents one such gram-negative enteric pathogenic group with more than 100 species, infecting humans and fish. The Vibrio spp. is demarcated into two groups, one that causes cholera and the other producing non-cholera or vibriosis infections. People who encounter contaminated water are at risk, but young children and pregnant women are the most vulnerable. Though controllable, Vibrio infection still necessitates the development of preventative measures, such as vaccinations, that can lessen the severity of the infection and reduce reliance on antibiotic use. With emerging multi-drug resistant strains, efforts are needed to develop newer vaccines, such as subunit-based or outer membrane vesicle-based. Thus, this review strives to bring together available information about Vibrio spp. outer membrane proteins and vesicles, encompassing their structure, function, and immunoprotective role.
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Affiliation(s)
- Brijeshwar Singh
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology, Indore, India
| | - Surbhi Jaiswal
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology, Indore, India
| | - Prashant Kodgire
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology, Indore, India
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Nayak S, Akshay SD, Deekshit VK, Raj JM, Maiti B. Exposure to imipenem at sub-minimum inhibitory concentration leads to altered expression of major outer membrane proteins in Acinetobacter baumannii. J Appl Microbiol 2024; 135:lxae105. [PMID: 38653725 DOI: 10.1093/jambio/lxae105] [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: 02/06/2024] [Revised: 04/15/2024] [Accepted: 04/22/2024] [Indexed: 04/25/2024]
Abstract
AIMS Acinetobacter baumannii is a nosocomial pathogen known to be multidrug-resistant (MDR), especially to drugs of the carbapenem class. Several factors contribute to resistance, including efflux pumps, β-lactamases, alteration of target sites, and permeability defects. In addition, outer membrane proteins (OMPs), like porins are involved in the passage of antibiotics, and their alteration could lead to resistance development. This study aimed to explore the possible involvement of porins and OMPs in developing carbapenem resistance due to differential expression. METHODS AND RESULTS The antibiotic-susceptible and MDR isolates of A. baumannii were first studied for differences in their transcriptional levels of OMP expression and OMP profiles. The antibiotic-susceptible isolates were further treated with imipenem, and it was found that the omp genes were differentially expressed. Six of the nine genes studied were upregulated at 1 h of exposure to imipenem. Their expression gradually decreased with time, further confirmed by their OMP profile and two-dimensional gel electrophoresis. CONCLUSIONS This study could identify OMPs that were differentially expressed on exposure to imipenem. Hence, this study provides insights into the role of specific OMPs in antibiotic resistance in A. baumannii.
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Affiliation(s)
- Srajana Nayak
- Nitte (Deemed to be University), Nitte University Centre for Science Education and Research, Department of Bio & Nano Technology, Deralakatte, Mangaluru 575018, India
| | - Sadanand Dangari Akshay
- Nitte (Deemed to be University), Nitte University Centre for Science Education and Research, Department of Bio & Nano Technology, Deralakatte, Mangaluru 575018, India
| | - Vijaya Kumar Deekshit
- Nitte (Deemed to be University), Nitte University Centre for Science Education and Research, Department of Infectious Diseases & Microbial Genomics, Deralakatte, Mangaluru 575018, India
| | - Juliet Mohan Raj
- Nitte (Deemed to be University), Nitte University Centre for Science Education and Research, Department of Infectious Diseases & Microbial Genomics, Deralakatte, Mangaluru 575018, India
| | - Biswajit Maiti
- Nitte (Deemed to be University), Nitte University Centre for Science Education and Research, Department of Bio & Nano Technology, Deralakatte, Mangaluru 575018, India
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Kho ZY, Azad MAK, Zhu Y, Han ML, Zhou QT, Velkov T, Naderer T, Li J. Transcriptomic interplay between Acinetobacter baumannii , human macrophage and polymyxin. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.23.576770. [PMID: 38328180 PMCID: PMC10849618 DOI: 10.1101/2024.01.23.576770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
Optimization of antibiotic therapy has been hindered by our dearth of understanding on the mechanism of the host-pathogen-drug interactions. Here, we employed dual RNA-sequencing to examine transcriptomic perturbations in response to polymyxin B in a co-culture infection model of Acinetobacter baumannii and human macrophages. Our findings revealed that polymyxin B treatment induced significant transcriptomic response in macrophage-interacting A. baumannii , exacerbating bacterial oxidative stress, disrupting metal homeostasis, affecting osmoadaptation, triggering stringent stress response, and influencing pathogenic factors. Moreover, infected macrophages adapt heme catabolism, coagulation cascade, and hypoxia-inducible signaling to confront bacterial invasion. Disrupting rcnB , ompW , and traR/dksA genes in A. baumannii impairs metal homeostasis, osmotic stress defense and stringent responses, thereby enhancing antibacterial killing by polymyxin. These findings shed light on the global stress adaptations at the network level during host-pathogen-drug interactions, revealing promising therapeutic targets for further investigation. IMPORTANCE In the context of the development of bacterial resistance during the course of antibiotic therapy, the role of macrophages in shaping bacterial response to antibiotic killing remains enigmatic. Herein we employed dual RNA-sequencing and an in vitro tripartite model to delve into the unexplored transcriptional networks of the Acinetobacter baumannii -macrophage-polymyxin axis. Our findings uncovered the potential synergy between macrophages and polymyxin B which appear to act in co-operation to disrupt multiple stress tolerance mechanisms in A. baumannii . Notably, we discovered the critical roles of bacterial nickel/cobalt homeostasis ( rcnB family), osmotic stress defense ( ompW family), and stringent response regulator ( traR/dksA C4-type zinc finger) in tolerating the last-line antibiotic polymyxin B. Our findings may lead to potential targets for the development of novel therapeutics against the problematic pathogen A. baumannii .
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Marques PH, Rodrigues TCV, Santos EH, Bleicher L, Aburjaile FF, Martins FS, Oliveira CJF, Azevedo V, Tiwari S, Soares S. Design of a multi-epitope vaccine (vme-VAC/MST-1) against cholera and vibriosis based on reverse vaccinology and immunoinformatics approaches. J Biomol Struct Dyn 2023:1-16. [PMID: 38112302 DOI: 10.1080/07391102.2023.2293256] [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: 02/08/2023] [Accepted: 11/25/2023] [Indexed: 12/21/2023]
Abstract
Vibriosis and cholera are serious diseases distributed worldwide and caused by six marine bacteria of the Vibrio genus. Thousands of deaths occur each year due to these illnesses, necessitating the development of new preventive measures. Presently, the existing cholera vaccine demonstrates an effectiveness of approximately 60%. Here we describe a new multi-epitope vaccine, 'vme-VAC/MST-1' based on vaccine targets identified by reverse vaccinology and epitopes predicted by immunoinformatics, two currently effective tools for predicting new vaccines for bacterial pathogens. The vaccine was designed to combat vibriosis and cholera by incorporating epitopes predicted for CTL, HTL, and B cells. These epitopes were identified from six vaccine targets revealed through subtractive genomics, combined with reverse vaccinology, and were further filtered using immunoinformatics approaches based on their predicted immunogenicity. To construct the vaccine, 28 epitopes (24 CTL/B and 4 HTL/B) were linked to the sequence of the cholera toxin B subunit adjuvant. In silico analyses indicate that the resulting immunogen is stable, soluble, non-toxic, and non-allergenic. Furthermore, it exhibits no homology to the host and demonstrates a strong capacity to elicit innate, B-cell, and T-cell immune responses. Our analysis suggests that it is likely to elicit immune reactions mediated through the TLR5 pathway, as evidenced by the molecular docking of the vaccine with the receptor, which revealed high affinity and a favorable reaction. Thus, vme-VAC/MST-1 is predicted to be a safe and effective solution against pathogenic Vibrio spp. However, further experimental analyses are required to measure the vaccine's effects In vivo.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Pedro Henrique Marques
- Institute of Biological Sciences, Post-graduate Interunits Program in Bioinformatics, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
- Department of Preventive Veterinary Medicine, School of Veterinary Medicine, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
| | - Thais Cristina Vilela Rodrigues
- Department of Genetics, Ecology and Evolution, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
| | - Eduardo Horta Santos
- Institute of Biological Sciences, Post-graduate Interunits Program in Bioinformatics, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
- Department of Biochemistry and Immunology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
| | - Lucas Bleicher
- Department of Biochemistry and Immunology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
| | - Flavia Figueira Aburjaile
- Department of Preventive Veterinary Medicine, School of Veterinary Medicine, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
| | - Flaviano S Martins
- Department of Microbiology, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
| | - Carlo Jose Freire Oliveira
- Department of Microbiology, Immunology and Parasitology, Institute of Biological Sciences, Federal University of Triângulo Mineiro, Uberaba, MG, Brazil
| | - Vasco Azevedo
- Department of Genetics, Ecology and Evolution, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
| | - Sandeep Tiwari
- Institute of Biology, Federal University of Bahia, Salvador, BA, Brazil
- Institute of Health Sciences, Federal University of Bahia, Salvador, BA, Brazil
| | - Siomar Soares
- Department of Microbiology, Immunology and Parasitology, Institute of Biological Sciences, Federal University of Triângulo Mineiro, Uberaba, MG, Brazil
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Pandey R, Sharma S, Sinha KK. Evidence of Antibiotic Resistance and Virulence Factors in Environmental Isolates of Vibrio Species. Antibiotics (Basel) 2023; 12:1062. [PMID: 37370381 DOI: 10.3390/antibiotics12061062] [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: 05/01/2023] [Revised: 06/03/2023] [Accepted: 06/15/2023] [Indexed: 06/29/2023] Open
Abstract
The outbreak of waterborne diseases such as cholera and non-cholera (vibriosis) is continuously increasing in the environment due to fecal and sewage discharge in water sources. Cholera and vibriosis are caused by different species of Vibrio genus which are responsible for acute diarrheal disease and soft tissue damage. Although incidences of cholera and vibriosis have been reported from the Vaishali district of Bihar, India, clinical or environmental strains have not been characterized in this region. Out of fifty environmental water samples, twelve different biochemical test results confirmed the presence of twenty Vibrio isolates. The isolates were found to belong to five different Vibrio species, namely V. proteolyticus, V. campbellii, V. nereis, V. cincinnatiensis, and V. harveyi. From the identified isolates, 65% and 45% isolates were found to be resistant to ampicillin and cephalexin, respectively. Additionally, two isolates were found to be resistant against six and four separately selected antibiotics. Furthermore, virulent hlyA and ompW genes were detected by PCR in two different isolates. Additionally, phage induction was also noticed in two different isolates which carry lysogenic phage in their genome. Overall, the results reported the identification of five different Vibrio species in environmental water samples. The isolates showed multiple antibacterial resistance, phage induction, and virulence gene profile in their genome.
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Affiliation(s)
- Rajkishor Pandey
- Department of Biotechnology, National Institute of Pharmaceutical Education and Research, Hajipur 844102, Bihar, India
- School of Medicine, University of Missouri, Columbia, MO 65211, USA
| | - Simran Sharma
- Department of Basic and Applied Sciences, National Institute of Food Technology Entrepreneurship & Management (NIFTEM), Kundli, Sonipat 131028, Haryana, India
| | - Kislay Kumar Sinha
- Department of Biotechnology, National Institute of Pharmaceutical Education and Research, Hajipur 844102, Bihar, India
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PHB production from food waste hydrolysates by Halomonas bluephagenesis Harboring PHB operon linked with an essential gene. Metab Eng 2023; 77:12-20. [PMID: 36889504 DOI: 10.1016/j.ymben.2023.03.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 03/05/2023] [Indexed: 03/08/2023]
Abstract
Food wastes can be hydrolyzed into soluble microbial substrates, contributing to sustainability. Halomonas spp.-based Next Generation Industrial Biotechnology (NGIB) allows open, unsterile fermentation, eliminating the need for sterilization to avoid the Maillard reaction that negatively affects cell growth. This is especially important for food waste hydrolysates, which have a high nutrient content but are unstable due to batch, sources, or storage conditions. These make them unsuitable for polyhydroxyalkanoate (PHA) production, which usually requires limitation on either nitrogen, phosphorous, or sulfur. In this study, H. bluephagenesis was constructed by overexpressing the PHA synthesis operon phaCABCn (cloned from Cupriavidus necator) controlled by the essential gene ompW (encoding outer membrane protein W) promoter and the constitutive porin promoter that are continuously expressed at high levels throughout the cell growth process, allowing poly(3-hydroxybutyrate) (PHB) production to proceed in nutrient-rich (also nitrogen-rich) food waste hydrolysates of various sources. The recombinant H. bluephagenesis termed WZY278 generated 22 g L-1 cell dry weight (CDW) containing 80 wt% PHB when cultured in food waste hydrolysates in shake flasks, and it was grown to 70 g L-1 CDW containing 80 wt% PHB in a 7-L bioreactor via fed-batch cultivation. Thus, unsterilizable food waste hydrolysates can become nutrient-rich substrates for PHB production by H. bluephagenesis able to be grown contamination-free under open conditions.
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Barut D, Enuh BM, Derkuş B, Güler Ü, Salih B, Aytar Çelik P. The relationship between bacterial outer membrane vesicles and halophilic adaptation. Mol Omics 2023; 19:174-181. [PMID: 36597842 DOI: 10.1039/d2mo00259k] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Many cells are known to actively release nano-sized outer membrane vesicles (OMVs) that contain bioactive proteins, lipids, and nucleic acids into the extracellular environment. These vesicles have been associated with adaptation to environmental stress in other species, but their role in halophilic salt stress adaptation is not known. This study aimed to isolate and characterize the OMVs of Halomonas caseinilytica KB2 at various salt concentrations [6% (KB2-6), 12% (KB2-12), and 18% (KB2-18)] and to identify the patterns of adaptations to increasing salinity in its structure, protein composition, and expression. Also, a comparison with the composition of OMVs of E. coli, a mesophilic bacterium, was performed. Bioinformatics and statistical analysis were carried out to elucidate the underlying proteome differences that may exist as a result of increasing salinity. The results show that OMV production in H. caseinilytica KB2 is promoted by a decrease in salinity. OMVs also revealed possible structural and metabolic changes happening in the cells which led to the deduction that cells become more stable with increasing salt concentrations. Cell wall integrity, protein expression and folding are important. Although H. caseinilytica KB2 OMVs show cellular changes with changing salt concentration, they may not play a direct role in adaptation to changing salinity.
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Affiliation(s)
- Dilan Barut
- Department of Biotechnology and Biosafety, Graduate School of Natural and Applied Science, Eskisehir Osmangazi University, 26040 Eskisehir, Turkey.
| | - Blaise M Enuh
- Department of Biotechnology and Biosafety, Graduate School of Natural and Applied Science, Eskisehir Osmangazi University, 26040 Eskisehir, Turkey.
| | - Burak Derkuş
- Department of Chemistry, Faculty of Science, Ankara University, 06560, Ankara, Turkey
| | - Ülkü Güler
- Department of Chemistry, Hacettepe University, Ankara 06800, Turkey
| | - Bekir Salih
- Department of Chemistry, Hacettepe University, Ankara 06800, Turkey
| | - Pınar Aytar Çelik
- Department of Biotechnology and Biosafety, Graduate School of Natural and Applied Science, Eskisehir Osmangazi University, 26040 Eskisehir, Turkey. .,Environmental Protection and Control Program, Eskişehir Osmangazi University, Eskişehir 26110, Turkey
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8
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Alexpandi R, Abirami G, Murugesan B, Durgadevi R, Swasthikka RP, Cai Y, Ragupathi T, Ravi AV. Tocopherol-assisted magnetic Ag-Fe 3O 4-TiO 2 nanocomposite for photocatalytic bacterial-inactivation with elucidation of mechanism and its hazardous level assessment with zebrafish model. JOURNAL OF HAZARDOUS MATERIALS 2023; 442:130044. [PMID: 36179621 DOI: 10.1016/j.jhazmat.2022.130044] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Revised: 09/18/2022] [Accepted: 09/19/2022] [Indexed: 06/16/2023]
Abstract
In recent years, many endeavours have been prompted with photocatalytic nanomaterials by the need to eradicate pathogenic microorganisms from water bodies. Herein, a tocopherol-assisted Ag-Fe3O4-TiO2 nanocomposite (TAFTN) was synthesized for photocatalytic bacterial inactivation. The prepared TAFTN became active under sunlight due to its narrowed bandgap, inactivating the bacterial contaminants via photo-induced ROS stress. The ROS radicals destroy bacteria by creating oxidative stress, which damages the cell membrane and cellular components such as nucleic acids and proteins. For the first time, the nano-LC-MS/MS-based quantitative proteomics reveals that the disrupted proteins are involved in a variety of cellular functions; the most of these are involved in the metabolic pathway, eventually leading to bacterial death during TAFTN-photocatalysis under sunlight. Furthermore, the toxicity analysis confirmed that the inactivated bacteria seemed to have no detrimental impact on zebrafish model, showing that the disinfected water via TAFTN-photocatalysis is enormously safe. Furthermore, the TAFTN-photocatalysis successfully killed the bacterial cells in natural seawater, indicating the consistent photocatalytic efficacy when recycled repeatedly. The results of this work demonstrate that the produced nanocomposite might be a powerful recyclable and sunlight-active photocatalyst for environmental water treatment.
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Affiliation(s)
- Rajaiah Alexpandi
- Lab in Microbiology and Marine Biotechnology, Department of Biotechnology, School of Biological Sciences, Alagappa University, Karaikudi 630 003, India
| | - Gurusamy Abirami
- Lab in Microbiology and Marine Biotechnology, Department of Biotechnology, School of Biological Sciences, Alagappa University, Karaikudi 630 003, India
| | - Balaji Murugesan
- The Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Ministry of Education, National Engineering Lab for Textile Fiber Materials and Processing Technology, School of Materials Science and Engineering, Zhejiang Sci-Tech University, Hangzhou 310018, PR China; Department of Mechanical Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, South Korea
| | - Ravindran Durgadevi
- Lab in Microbiology and Marine Biotechnology, Department of Biotechnology, School of Biological Sciences, Alagappa University, Karaikudi 630 003, India
| | - Roshni Prithiviraj Swasthikka
- Lab in Microbiology and Marine Biotechnology, Department of Biotechnology, School of Biological Sciences, Alagappa University, Karaikudi 630 003, India
| | - Yurong Cai
- The Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Ministry of Education, National Engineering Lab for Textile Fiber Materials and Processing Technology, School of Materials Science and Engineering, Zhejiang Sci-Tech University, Hangzhou 310018, PR China
| | - Thennarasu Ragupathi
- Lab in Microbiology and Marine Biotechnology, Department of Biotechnology, School of Biological Sciences, Alagappa University, Karaikudi 630 003, India
| | - Arumugam Veera Ravi
- Lab in Microbiology and Marine Biotechnology, Department of Biotechnology, School of Biological Sciences, Alagappa University, Karaikudi 630 003, India.
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Chen X, Shao Z, Wu L, He B, Yang W, Chen J, Jin E, Huang Q, Lei L, Xu J, Li H, Zhang H, Wan Y, Liu W, Zhou R. Involvement of the Actinobacillus pleuropneumoniae ompW Gene in Confrontation of Environmental Pressure. Front Vet Sci 2022; 9:846322. [PMID: 35664844 PMCID: PMC9161549 DOI: 10.3389/fvets.2022.846322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 04/28/2022] [Indexed: 11/13/2022] Open
Abstract
Actinobacillus pleuropneumoniae causes porcine pleuropneumonia. The function of the outer membrane protein W gene (ompW) of A. pleuropneumoniae has not been evaluated. Thus a deletion mutant of ompW, ΔompW, was constructed to explore the effect of ompW gene deletion on bacterial growth, biofilm formation, bacterial morphology, oxidative tolerance, susceptibility to antibiotics, and the expression of ribosome synthesis and ABC transporter related genes. Results showed that the ompW gene deletion did not affect biofilm formation and the growth of A. pleuropneumoniae but did affect bacterial morphology during steady growth, oxidative tolerance, and bacterial susceptibility to polymyxin B, kanamycin, and penicillin. The ompW gene deletion also affected the expression of ribosome synthesis and ABC transporter related genes. These results suggested that ompW may regulate the biological phenotype of A. pleuropneumoniae.
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Affiliation(s)
- Xiabing Chen
- Institute of Animal Husbandry and Veterinary Science, Wuhan Academy of Agricultural Sciences, Wuhan, China
- *Correspondence: Xiabing Chen
| | - Zhiyong Shao
- Institute of Animal Husbandry and Veterinary Science, Wuhan Academy of Agricultural Sciences, Wuhan, China
| | - Lijun Wu
- Institute of Animal Husbandry and Veterinary Science, Wuhan Academy of Agricultural Sciences, Wuhan, China
| | - Bin He
- Institute of Animal Husbandry and Veterinary Science, Wuhan Academy of Agricultural Sciences, Wuhan, China
| | - Wenhai Yang
- Institute of Animal Husbandry and Veterinary Science, Wuhan Academy of Agricultural Sciences, Wuhan, China
| | - Jie Chen
- Institute of Animal Husbandry and Veterinary Science, Wuhan Academy of Agricultural Sciences, Wuhan, China
| | - Erguang Jin
- Institute of Animal Husbandry and Veterinary Science, Wuhan Academy of Agricultural Sciences, Wuhan, China
| | - Qi Huang
- State Key Laboratory of Agricultural Microbiology, College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- Cooperative Innovation Center for Sustainable Pig Production, College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Liancheng Lei
- College of Veterinary Medicine and College of Animal Science, Jilin University, Changchun, China
| | - Jiajia Xu
- State Key Laboratory of Agricultural Microbiology, College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- Cooperative Innovation Center for Sustainable Pig Production, College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Haotian Li
- State Key Laboratory of Agricultural Microbiology, College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- Cooperative Innovation Center for Sustainable Pig Production, College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Hui Zhang
- State Key Laboratory of Agricultural Microbiology, College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- Cooperative Innovation Center for Sustainable Pig Production, College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Yun Wan
- Wuhan Animal Disease Control Center, Wuhan, China
| | - Wu Liu
- Institute of Animal Husbandry and Veterinary Science, Wuhan Academy of Agricultural Sciences, Wuhan, China
- Wu Liu
| | - Rui Zhou
- State Key Laboratory of Agricultural Microbiology, College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- Cooperative Innovation Center for Sustainable Pig Production, College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- Rui Zhou
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Li A, Shi C, Qian S, Wang Z, Zhao S, Liu Y, Xue Z. Evaluation of antibiotic combination of Litsea cubeba essential oil on Vibrio parahaemolyticus inhibition mechanism and anti-biofilm ability. Microb Pathog 2022; 168:105574. [PMID: 35561981 DOI: 10.1016/j.micpath.2022.105574] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 05/04/2022] [Accepted: 05/08/2022] [Indexed: 10/18/2022]
Abstract
Vibrio parahaemolyticus (V. parahaemolyticus) is a common pathogen in seafood. The use of antibiotics is a primary tool to prevent and control V. parahaemolyticus in the aquaculture industry. However, V. parahaemolyticus combats the damage caused by antibiotics by forming biofilms under certain conditions. In this study, we analyzed the antibacterial effect and the characteristics of V. parahaemolyticus by experimentally determining the minimum inhibitory concentration (MIC) and the fractional inhibitory concentration index (FICI) values of a combination of the Litsea cubeba essential oil (LCEO) and several commonly used V. parahaemolyticus antibiotics. The bactericidal effect of the essential oil alone and essential oil in combination with the antibiotics were evaluated with time-kill curves. The damage to cell membranes and cell walls were assessed by measuring the content of macromolecules and alkaline phosphatase (AKP) released into the supernatant using V. parahaemolyticus ATCC17802 as the experimental strain. The membrane structure was observed by transmission electron microscopy. The results showed that the MIC value of the LCEO was 1,024 μg/mL, and the LCEO FICI values in combination with tetracycline or oxytetracycline hydrochloride was 0.3125 and 0.75, respectively, indicating synergistic and additive effects. Moreover, LCEO inhibited the growth and promoted the removal of biofilms by reducing the content of hydrophobic and extracellular polysaccharides on the cell surface. This study provides a reference for studying the antibacterial activity of LCEO and the combination of antibiotics to prevent and control the formation of biofilms by V. parahaemolyticus.
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Affiliation(s)
- Anqi Li
- College of Biology and Food Engineering, Anhui Polytechnic University, Wuhu, 241000, PR China; Anhui Engineering Laboratory for Industrial Microbiology Molecular Breeding, Wuhu, 241000, PR China
| | - Chenglong Shi
- College of Biology and Food Engineering, Anhui Polytechnic University, Wuhu, 241000, PR China; Anhui Engineering Laboratory for Industrial Microbiology Molecular Breeding, Wuhu, 241000, PR China
| | - Senhe Qian
- College of Biology and Food Engineering, Anhui Polytechnic University, Wuhu, 241000, PR China; Anhui Engineering Laboratory for Industrial Microbiology Molecular Breeding, Wuhu, 241000, PR China
| | - Zhou Wang
- College of Biology and Food Engineering, Anhui Polytechnic University, Wuhu, 241000, PR China; Anhui Engineering Laboratory for Industrial Microbiology Molecular Breeding, Wuhu, 241000, PR China.
| | - Shiguang Zhao
- College of Biology and Food Engineering, Anhui Polytechnic University, Wuhu, 241000, PR China; Anhui Engineering Laboratory for Industrial Microbiology Molecular Breeding, Wuhu, 241000, PR China; Xuancheng Industrial Technology, Research Institute of Anhui Polytechnic University, Anhui, Xuancheng, 242000, PR China
| | - Yan Liu
- College of Biology and Food Engineering, Anhui Polytechnic University, Wuhu, 241000, PR China; Anhui Engineering Laboratory for Industrial Microbiology Molecular Breeding, Wuhu, 241000, PR China
| | - Zhenglian Xue
- College of Biology and Food Engineering, Anhui Polytechnic University, Wuhu, 241000, PR China; Anhui Engineering Laboratory for Industrial Microbiology Molecular Breeding, Wuhu, 241000, PR China
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11
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Gil-Marqués ML, Pachón J, Smani Y. iTRAQ-Based Quantitative Proteomic Analysis of Acinetobacter baumannii under Hypoxia and Normoxia Reveals the Role of OmpW as a Virulence Factor. Microbiol Spectr 2022; 10:e0232821. [PMID: 35234505 PMCID: PMC8941935 DOI: 10.1128/spectrum.02328-21] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 02/02/2022] [Indexed: 11/20/2022] Open
Abstract
Acinetobacter baumannii needs to adapt to hypoxia during infection. Understanding its proteome regulation during infection would allow us to determine new targets to develop novel treatments. iTRAQ proteomic analysis of A549 cell infection by the ATCC 17978 strain was performed. A total of 175 proteins were differentially expressed under hypoxia versus normoxia. We selected the hypoxia-downregulated protein OmpW to analyze its role as a virulence factor. The loss of OmpW decreased the adherence and invasion of A. baumannii in these host cells, without affecting its bacterial growth. Moreover, A549 cell viability with ΔOmpW infection was higher than that with the wild-type strain. ΔOmpW presented less biofilm formation. Finally, the minimum lethal dose required by the ΔOmpW mutant was higher than that of the wild-type strain in a murine peritoneal sepsis model, with lower bacterial loads in tissues and fluids. Therefore, OmpW seems to be a virulence factor necessary for A. baumannii pathogenesis. IMPORTANCE Acinetobacter baumannii causes infections that are very difficult to treat due to the high rate of resistance to most and sometimes all of the antimicrobials used in the clinical setting. There is an important need to develop new strategies to combat A. baumannii infections. One alternative could be blocking specific bacterial virulence factors that this pathogen needs to infect cells. Pathogens modulate their protein expression as a function of the environment, and several studies have reported that hypoxia occurs in a wide range of infections. Therefore, it would be interesting to determine the proteome of A. baumannii under hypoxia in order to find new virulence factors, such as the outer membrane protein OmpW, as potential targets for the design of novel therapies.
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Affiliation(s)
- María Luisa Gil-Marqués
- Unit of Infectious Diseases, Microbiology and Preventive Medicine, Virgen del Rocío University Hospital, Seville, Spain
- Institute of Biomedicine of Seville, IBiS, University Hospital Virgen del Rocío/CSIC/University of Seville, Sevilla, Spain
| | - Jerónimo Pachón
- Institute of Biomedicine of Seville, IBiS, University Hospital Virgen del Rocío/CSIC/University of Seville, Sevilla, Spain
- Department of Medicine, University of Seville, Sevilla, Spain
| | - Younes Smani
- Unit of Infectious Diseases, Microbiology and Preventive Medicine, Virgen del Rocío University Hospital, Seville, Spain
- Institute of Biomedicine of Seville, IBiS, University Hospital Virgen del Rocío/CSIC/University of Seville, Sevilla, Spain
- CIBER de Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III, Madrid, Spain
- Department of Molecular Biology and Biochemical Engineering, Andalusian Center of Developmental Biology, CSIC, University of Pablo de Olavide, Seville, Spain
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12
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Chowdhury N, Hazarika DJ, Goswami G, Sarmah U, Borah S, Boro RC, Barooah M. Acid tolerant bacterium Bacillus amyloliquefaciens MBNC retains biocontrol efficiency against fungal phytopathogens in low pH. Arch Microbiol 2022; 204:124. [PMID: 34997335 DOI: 10.1007/s00203-021-02741-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 12/22/2021] [Accepted: 12/23/2021] [Indexed: 11/28/2022]
Abstract
Soil pH conditions have important consequences for microbial community structure, their dynamics, ecosystem processes, and interactions with plants. Low soil pH affects the growth and functional activity of bacterial biocontrol agents which may experience a paradigm shift in their ability to act antagonistically against fungal phytopathogens. In this study, the antifungal activity of an acid-tolerant soil bacterium Bacillus amyloliquefaciens MBNC was evaluated under low pH and compared to its activity in neutral pH conditions. Bacterial supernatant from 3-day-old culture (approximately 11.2 × 108 cells/mL) grown in low pH conditions was found more effective against fungal pathogens. B. amyloliquefaciens MBNC harboured genes involved in the synthesis of secondary metabolites of which surfactin homologues, with varying chain length (C11-C15), were identified through High-Resolution Mass Spectroscopy. The pH of the medium influenced the production of these metabolites. Surfactin C15 was exclusive to the extract of pH 4.5; production of iturinA and surfactin C11 was detected only in pH 7.0, while surfactin C12, C13 and C14 were detected in extracts of both the pH conditions. The secretion of phytohormones viz. indole acetic acid and gibberellic acid by B. amyloliquefaciens MBNC was detected in higher amounts in neutral condition compared to acidic condition. Although, secretion of metabolites and phytohormones in B. amyloliquefaciens MBNC was influenced by the pH condition of the medium, the isolate retained its antagonistic efficiency against several fungal phyto-pathogens under acidic condition.
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Affiliation(s)
- Naimisha Chowdhury
- DBT-North East Centre for Agricultural Biotechnology, Jorhat, Assam, 785013, India.,Department of Agricultural Biotechnology, Assam Agricultural University, Jorhat, Assam, 785013, India
| | - Dibya Jyoti Hazarika
- DBT-North East Centre for Agricultural Biotechnology, Jorhat, Assam, 785013, India.,Department of Agricultural Biotechnology, Assam Agricultural University, Jorhat, Assam, 785013, India
| | - Gunajit Goswami
- DBT-North East Centre for Agricultural Biotechnology, Jorhat, Assam, 785013, India
| | - Unmona Sarmah
- DBT-North East Centre for Agricultural Biotechnology, Jorhat, Assam, 785013, India
| | - Shrutirupa Borah
- Department of Agricultural Biotechnology, Assam Agricultural University, Jorhat, Assam, 785013, India
| | - Robin Chandra Boro
- Department of Agricultural Biotechnology, Assam Agricultural University, Jorhat, Assam, 785013, India
| | - Madhumita Barooah
- DBT-North East Centre for Agricultural Biotechnology, Jorhat, Assam, 785013, India. .,Department of Agricultural Biotechnology, Assam Agricultural University, Jorhat, Assam, 785013, India.
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13
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Grund ME, Choi Soo J, Cote CK, Berisio R, Lukomski S. Thinking Outside the Bug: Targeting Outer Membrane Proteins for Burkholderia Vaccines. Cells 2021; 10:cells10030495. [PMID: 33668922 PMCID: PMC7996558 DOI: 10.3390/cells10030495] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 02/18/2021] [Accepted: 02/22/2021] [Indexed: 12/16/2022] Open
Abstract
Increasing antimicrobial resistance due to misuse and overuse of antimicrobials, as well as a lack of new and innovative antibiotics in development has become an alarming global threat. Preventative therapeutics, like vaccines, are combative measures that aim to stop infections at the source, thereby decreasing the overall use of antibiotics. Infections due to Gram-negative pathogens pose a significant treatment challenge because of substantial multidrug resistance that is acquired and spread throughout the bacterial population. Burkholderia spp. are Gram-negative intrinsically resistant bacteria that are responsible for environmental and nosocomial infections. The Burkholderia cepacia complex are respiratory pathogens that primarily infect immunocompromised and cystic fibrosis patients, and are acquired through contaminated products and equipment, or via patient-to-patient transmission. The Burkholderia pseudomallei complex causes percutaneous wound, cardiovascular, and respiratory infections. Transmission occurs through direct exposure to contaminated water, water-vapors, or soil, leading to the human disease melioidosis, or the equine disease glanders. Currently there is no licensed vaccine against any Burkholderia pathogen. This review will discuss Burkholderia vaccine candidates derived from outer membrane proteins, OmpA, OmpW, Omp85, and Bucl8, encompassing their structures, conservation, and vaccine formulation.
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Affiliation(s)
- Megan E. Grund
- Department of Microbiology, Immunology and Cell Biology, School of Medicine, West Virginia University, Morgantown, WV 26506, USA; (M.E.G.); (S.J.C.)
| | - Jeon Choi Soo
- Department of Microbiology, Immunology and Cell Biology, School of Medicine, West Virginia University, Morgantown, WV 26506, USA; (M.E.G.); (S.J.C.)
| | - Christopher K. Cote
- Bacteriology Division, The United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Frederick, MD 21702, USA;
| | - Rita Berisio
- Institute of Biostructures and Bioimaging, National Research Council (CNR-IBB), 80145 Naples, Italy;
| | - Slawomir Lukomski
- Department of Microbiology, Immunology and Cell Biology, School of Medicine, West Virginia University, Morgantown, WV 26506, USA; (M.E.G.); (S.J.C.)
- Correspondence: ; Tel.: +1-304-293-6405
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14
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Liu J, Liu W, Xing S, Zhang X, He H, Chen J, Bielicki JK, Zhou M. Diversity of protease-producing bacteria in the soils of the South Shetland Islands, Antarctica. Antonie van Leeuwenhoek 2021; 114:457-464. [PMID: 33598877 DOI: 10.1007/s10482-021-01533-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Accepted: 02/08/2021] [Indexed: 12/01/2022]
Abstract
Proteases secreted from bacteria into soil play a key role in the degradation of organic nitrogen, which is the first and, usually, the rate-limiting step of nitrogen cycling. However, the diversity of protease-producing bacteria and their excreted proteases in Antarctic soil have not yet been fully explored. Here we studied 20 soil samples from the South Shetland Islands, Antarctica and isolated 253 strains with protease activity. These protease-producing bacteria belonged to the phyla Bacteroidetes, Proteobacteria, Actinobacteria, Firmicutes, and Deinococcus-Thermus. Thhe predominant genera were Arthrobacter (14.9%), Chryseobacterium (14.5%), Flavobacterium (14.5%), and Pseudomonas (14.5%). Most of these bacteria secreted serine proteases and metalloproteases. There was quite a large distribution in activity as quantified by protease and inhibition assays. Only a few strains secreted aspartic and/or cysteine proteases. Together these data provided novel insight into the diversity and mechanism of organic nitrogen degradation in Antarctic soils by various proteases, which may have potential in new biotechnological applications.
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Affiliation(s)
- Jianmin Liu
- School of Chemistry and Chemical Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, People's Republic of China
| | - Wenjie Liu
- School of Chemistry and Chemical Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, People's Republic of China
| | - Shu Xing
- School of Chemistry and Chemical Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, People's Republic of China
| | - Xiying Zhang
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, People's Republic of China
| | - Hailun He
- School of Life Sciences, State Key Laboratory of Medical Genetics, Central South University, Changsha, People's Republic of China
| | - Jianbin Chen
- School of Chemistry and Chemical Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, People's Republic of China
| | | | - Mingyang Zhou
- School of Chemistry and Chemical Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, People's Republic of China.
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15
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Medium Optimization and Proteome Analysis of Protease Production by Janthinobacterium sp. BIOTECHNOL BIOPROC E 2020. [DOI: 10.1007/s12257-020-0110-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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16
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Vibrio cholerae OmpR Contributes to Virulence Repression and Fitness at Alkaline pH. Infect Immun 2020; 88:IAI.00141-20. [PMID: 32284367 DOI: 10.1128/iai.00141-20] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2020] [Accepted: 04/05/2020] [Indexed: 12/13/2022] Open
Abstract
Vibrio cholerae is a Gram-negative human pathogen and the causative agent of the life-threatening disease cholera. V. cholerae is a natural inhabitant of marine environments and enters humans through the consumption of contaminated food or water. The ability to transition between aquatic ecosystems and the human host is paramount to the pathogenic success of V. cholerae The transition between these two disparate environments requires the expression of adaptive responses, and such responses are most often regulated by two-component regulatory systems such as the EnvZ/OmpR system, which responds to osmolarity and acidic pH in many Gram-negative bacteria. Previous work in our laboratory indicated that V. cholerae OmpR functioned as a virulence regulator through repression of the LysR-family transcriptional regulator aphB; however, the role of OmpR in V. cholerae biology outside virulence regulation remained unknown. In this work, we sought to further investigate the function of OmpR in V. cholerae biology by defining the OmpR regulon through RNA sequencing. This led to the discovery that V. cholerae ompR was induced at alkaline pH to repress genes involved in acid tolerance and virulence factor production. In addition, OmpR was required for V. cholerae fitness during growth under alkaline conditions. These findings indicate that V. cholerae OmpR has evolved the ability to respond to novel signals during pathogenesis, which may play a role in the regulation of adaptive responses to aid in the transition between the human gastrointestinal tract and the marine ecosystem.
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17
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He YU, Wang S, Yin X, Sun F, He B, Liu X. Comparison of Extracellular Proteins from Virulent and Avirulent Vibrio parahaemolyticus Strains To Identify Potential Virulence Factors. J Food Prot 2020; 83:155-162. [PMID: 31860395 DOI: 10.4315/0362-028x.jfp-19-188] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Vibrio parahaemolyticus is a leading seafood-borne pathogen that causes gastroenteritis, septicemia, and serious wound infections due to the actions of virulence-associated proteins. We compared the extracellular proteins of nonvirulent JHY20 and virulent ATCC 33847 V. parahaemolyticus reference strains. Eighteen extracellular proteins were identified from secretory profiles, and 11 (68.75%) of the 16 proteins in ATCC 33847 are associated with virulence and/or protection against adverse conditions: trigger factor, chaperone SurA, aspartate-semialdehyde dehydrogenase, 4-hydroxy-3-methylbut-2-en-1-yl diphosphate synthase, glutamate 5-kinase, alanine dehydrogenase, glyceraldehyde-3-phosphate dehydrogenase, outer membrane protein OmpV, ribosome-associated inhibitor A, chaperone protein Skp, and universal stress protein. Two nontoxic-related proteins, amino acid ABC transporter substrate-binding protein and an uncharacterized protein, were identified in JHY20. The results provide a theoretical basis for supporting safety risk assessment of aquatic foods, illuminate the pathogenic mechanisms of V. parahaemolyticus, and assist the identification of novel vaccine candidates for foodborne pathogens.
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Affiliation(s)
- Y U He
- College of Food (Biotechnology) Engineering.,Key Construction Laboratory of Food Resources Development and the Quality Safety, Xuzhou University of Technology, Jiangsu, Xuzhou 221018, People's Republic of China
| | - Shuai Wang
- College of Food (Biotechnology) Engineering.,Key Construction Laboratory of Food Resources Development and the Quality Safety, Xuzhou University of Technology, Jiangsu, Xuzhou 221018, People's Republic of China
| | | | - Fengjiao Sun
- Logistics & Security Department, Shanghai Civil Aviation College, Shanghai 201300, People's Republic of China
| | - Bin He
- Environment Monitoring Station, Zaozhuang Municipal Bureau of Ecology and Environment, Shandong 277100, People's Republic of China
| | - Xiao Liu
- Henan Key Laboratory of Cold Chain Food Quality and Safety Control, Zhengzhou University of Light Industry, Zhengzhou 450001, People's Republic of China
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18
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Menikpurage IP, Barraza D, Meléndez AB, Strebe S, Mera PE. The B12 receptor BtuB alters the membrane integrity of Caulobacter crescentus. MICROBIOLOGY-SGM 2019; 165:311-323. [PMID: 30628887 DOI: 10.1099/mic.0.000753] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Vitamin B12 is one of the most complex biomolecules in nature. Since few organisms can synthesize B12de novo, most bacteria utilize highly sensitive and specialized transporters to scavenge B12 and its precursors. In Gram-negative bacteria, BtuB is the outer membrane TonB-dependent receptor for B12. In the fresh water bacterium Caulobacter crescentus, btuB is among the most highly expressed genes. In this study, we characterized the function of BtuB in C. crescentus and unveiled a potential new function of this receptor involved in cellular fitness. Under standard minimal or rich growth conditions, we found that supplements of vitamin B12 to cultures of C. crescentus provided no significant advantage in growth rate. Using a B12 methionine auxotroph, we showed that BtuB in C. crescentus is capable of transporting B12 at low pico-molar range. A btuB knockout strain displayed higher sensitivity to detergents and to changes in osmotic pressure compared to the wild-type. Electron micrographs of this knockout strain revealed a morphology defect. The sensitivity observed in the btuB knockout strain was not due to changes in membrane permeability or altered S-layer levels. Our results demonstrate that btuB deletion mutants exhibit increased susceptibility to membrane stressors, suggesting a potential role of this receptor in membrane homeostasis. Because we only tested BtuB's function under laboratory conditions, we cannot eliminate the possibility that BtuB also plays a key role as a B12 scavenger in C. crescentus when growing in its highly variable and nutrient-limited natural environment.
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Affiliation(s)
- Inoka P Menikpurage
- Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, NM 88003, USA
| | - Daniela Barraza
- Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, NM 88003, USA
| | - Ady B Meléndez
- Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, NM 88003, USA
| | - Sierra Strebe
- Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, NM 88003, USA
| | - Paola E Mera
- Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, NM 88003, USA
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