1
|
Zhang Z, Wang Z, Zhang T, Yin B, Li R, Sheng Z, Li S. Variations in soil microbial communities in different saline soils under typical Populus spp. vegetation in alpine region of the Qaidam Basin, NW China. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2024; 282:116747. [PMID: 39024946 DOI: 10.1016/j.ecoenv.2024.116747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Revised: 07/11/2024] [Accepted: 07/15/2024] [Indexed: 07/20/2024]
Abstract
Salinization is a severe threat to agriculture and the environment in many areas, and the same in Qaidam Basin, Qinghai Province, Northwestern China. Microorganisms have an important influence on regulating the biochemical cycles of ecosystems; however, systematic research exploring microbial diversity and interactions with saline-soil ecosystems' environmental variables remains scarce. Thus, 16 S rRNA high-throughput sequencing was performed in this paper to characterize microbial diversity under different levels of salinized soils: non-salinized (NS, 2.25 g/L), moderately salinized (MS, 6.14 g/L) and highly salinized (HS, 9.82 g/L). The alpha diversity results showed that the HS soil was significantly different from the NS and MS soils. An analysis of similarity (ANOSIM) and a principal co-ordinates analysis (PCoA) indicated that NS and MS clustered closely while HS separated from the other two. Significant differences in microbial composition were observed at the taxonomic level. Proteobacteria (42.29-79.23 %) were the most abundant phyla in the studied soils. Gammaproteobacteria (52.49 and 66.61 %) had higher abundance in the MS and HS soils at the class level; Methylophaga and Pseudomonas were the predominant bacteria in the HS soil; and Azotobacter and Methylobacillus were abundant in the MS soil. Most genera belonging to Proteobacteria and Actinobacteria were detected via a linear discriminate analysis (LDA) effect size (LEfSe) analysis, which indicated that microbes with the ability to degrade organic matter and accomplish nutrient cycling can be well-adapted to salt conditions. Further analyses (redundancy analysis and Mantel test) showed that the microbial communities were mainly related to the soil salinity, electrical conductivity (EC1:5), total phosphorus (TP) and ammonia nitrogen (NH4+-N). Overall, the findings of the study can provide insights for better understanding the dominant indigenous microbes and their roles in biochemical cycles in different saline soils in the Qaidam Basin, Qinghai Province, China. The researches related to microbial community under typical poplar species should further clarify the mechanism of plant-microbial interaction and benefit for microbial utilization in salt soil remediation.
Collapse
Affiliation(s)
- Zhenzhong Zhang
- Department of Hydraulic Engineering, Tsinghua University, Beijing 100084, China
| | - Zhongjing Wang
- Department of Hydraulic Engineering, Tsinghua University, Beijing 100084, China; Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration in Northwest China, Ningxia University, Yinchuan 750021, China.
| | - Tan Zhang
- Rizhao River and Lake Management and Protection Center, Rizhao 276800, China
| | - Baosi Yin
- Yunnan Traffic Science Research Institute Co. Ltd., Kunming 650000, China
| | - Runjie Li
- State Key Laboratory of Plateau Ecology and Agriculture, College of Agriculture and Animal Husbandry, Qinghai University, Xining 810016, China
| | - Zhuping Sheng
- Texas A&M AgriLife Research Center, El Paso TX 79927, USA
| | - Shen Li
- Australian National University, Canberra, ACT 2601, Australia
| |
Collapse
|
2
|
Nerber HN, Baloh M, Brehm JN, Sorg JA. The small acid-soluble proteins of Clostridioides difficile regulate sporulation in a SpoIVB2-dependent manner. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.05.17.541253. [PMID: 37292792 PMCID: PMC10245694 DOI: 10.1101/2023.05.17.541253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Clostridioides difficile is a pathogen whose transmission relies on the formation of dormant endospores. Spores are highly resilient forms of bacteria that resist environmental and chemical insults. In recent work, we found that C. difficile SspA and SspB, two small acid-soluble proteins (SASPs), protect spores from UV damage and, interestingly, are necessary for the formation of mature spores. Here, we build upon this finding and show that C. difficile sspA and sspB are required for the formation of the spore cortex layer. Moreover, using an EMS mutagenesis selection strategy, we identified mutations that suppressed the defect in sporulation of C. difficile SASP mutants. Many of these strains contained mutations in CDR20291_0714 (spoIVB2) revealing a connection between the SpoIVB2 protease and the SASPs in the sporulation pathway. This work builds upon the hypothesis that the small acid-soluble proteins can regulate gene expression.
Collapse
Affiliation(s)
- Hailee N Nerber
- Department of Biology, Texas A&M University, College Station, TX 77845
| | - Marko Baloh
- Department of Biology, Texas A&M University, College Station, TX 77845
| | - Joshua N Brehm
- Department of Biology, Texas A&M University, College Station, TX 77845
| | - Joseph A Sorg
- Department of Biology, Texas A&M University, College Station, TX 77845
| |
Collapse
|
3
|
Di Bella S, Sanson G, Monticelli J, Zerbato V, Principe L, Giuffrè M, Pipitone G, Luzzati R. Clostridioides difficile infection: history, epidemiology, risk factors, prevention, clinical manifestations, treatment, and future options. Clin Microbiol Rev 2024; 37:e0013523. [PMID: 38421181 DOI: 10.1128/cmr.00135-23] [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] [Indexed: 03/02/2024] Open
Abstract
SUMMARYClostridioides difficile infection (CDI) is one of the major issues in nosocomial infections. This bacterium is constantly evolving and poses complex challenges for clinicians, often encountered in real-life scenarios. In the face of CDI, we are increasingly equipped with new therapeutic strategies, such as monoclonal antibodies and live biotherapeutic products, which need to be thoroughly understood to fully harness their benefits. Moreover, interesting options are currently under study for the future, including bacteriophages, vaccines, and antibiotic inhibitors. Surveillance and prevention strategies continue to play a pivotal role in limiting the spread of the infection. In this review, we aim to provide the reader with a comprehensive overview of epidemiological aspects, predisposing factors, clinical manifestations, diagnostic tools, and current and future prophylactic and therapeutic options for C. difficile infection.
Collapse
Affiliation(s)
- Stefano Di Bella
- Clinical Department of Medical, Surgical and Health Sciences, Trieste University, Trieste, Italy
| | - Gianfranco Sanson
- Clinical Department of Medical, Surgical and Health Sciences, Trieste University, Trieste, Italy
| | - Jacopo Monticelli
- Infectious Diseases Unit, Trieste University Hospital (ASUGI), Trieste, Italy
| | - Verena Zerbato
- Infectious Diseases Unit, Trieste University Hospital (ASUGI), Trieste, Italy
| | - Luigi Principe
- Microbiology and Virology Unit, Great Metropolitan Hospital "Bianchi-Melacrino-Morelli", Reggio Calabria, Italy
| | - Mauro Giuffrè
- Clinical Department of Medical, Surgical and Health Sciences, Trieste University, Trieste, Italy
- Department of Internal Medicine (Digestive Diseases), Yale School of Medicine, Yale University, New Haven, Connecticut, USA
| | - Giuseppe Pipitone
- Infectious Diseases Unit, ARNAS Civico-Di Cristina Hospital, Palermo, Italy
| | - Roberto Luzzati
- Clinical Department of Medical, Surgical and Health Sciences, Trieste University, Trieste, Italy
| |
Collapse
|
4
|
Nerber HN, Sorg JA. The small acid-soluble proteins of spore-forming organisms: similarities and differences in function. Anaerobe 2024; 87:102844. [PMID: 38582142 DOI: 10.1016/j.anaerobe.2024.102844] [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: 01/11/2024] [Revised: 03/22/2024] [Accepted: 03/27/2024] [Indexed: 04/08/2024]
Abstract
The small acid-soluble proteins are found in all endospore-forming organisms and are a major component of spores. Through their DNA binding capabilities, the SASPs shield the DNA from outside insults (e.g., UV and genotoxic chemicals). The absence of the major SASPs results in spores with reduced viability when exposed to UV light and, in at least one case, the inability to complete sporulation. While the SASPs have been characterized for decades, some evidence suggests that using newer technologies to revisit the roles of the SASPs could reveal novel functions in spore regulation.
Collapse
Affiliation(s)
- Hailee N Nerber
- Department of Biology, Texas A&M University, College Station, TX, United States
| | - Joseph A Sorg
- Department of Biology, Texas A&M University, College Station, TX, United States.
| |
Collapse
|
5
|
Mehdizadeh Gohari I, Gonzales JL, Uzal FA, McClane BA. Overexpressing the cpr1953 Orphan Histidine Kinase Gene in the Absence of cpr1954 Orphan Histidine Kinase Gene Expression, or Vice Versa, Is Sufficient to Obtain Significant Sporulation and Strong Production of Clostridium perfringens Enterotoxin or Spo0A by Clostridium perfringens Type F Strain SM101. Toxins (Basel) 2024; 16:195. [PMID: 38668620 PMCID: PMC11053440 DOI: 10.3390/toxins16040195] [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: 03/13/2024] [Revised: 04/03/2024] [Accepted: 04/10/2024] [Indexed: 04/29/2024] Open
Abstract
The CPR1953 and CPR1954 orphan histidine kinases profoundly affect sporulation initiation and Clostridium perfringens enterotoxin (CPE) production by C. perfringens type F strain SM101, whether cultured in vitro (modified Duncan-Strong sporulation medium (MDS)) or ex vivo (mouse small intestinal contents (MIC)). To help distinguish whether CPR1953 and CPR1954 act independently or in a stepwise manner to initiate sporulation and CPE production, cpr1953 and cpr1954 null mutants of SM101 were transformed with plasmids carrying the cpr1954 or cpr1953 genes, respectively, causing overexpression of cpr1954 in the absence of cpr1953 expression and vice versa. RT-PCR confirmed that, compared to SM101, the cpr1953 mutant transformed with a plasmid encoding cpr1954 expressed cpr1954 at higher levels while the cpr1954 mutant transformed with a plasmid encoding cpr1953 expressed higher levels of cpr1953. Both overexpressing strains showed near wild-type levels of sporulation, CPE toxin production, and Spo0A production in MDS or MIC. These findings suggest that CPR1953 and CPR1954 do not function together in a step-wise manner, e.g., as a novel phosphorelay. Instead, it appears that, at natural expression levels, the independent kinase activities of both CPR1953 and CPR1954 are necessary for obtaining sufficient Spo0A production and phosphorylation to initiate sporulation and CPE production.
Collapse
Affiliation(s)
- Iman Mehdizadeh Gohari
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15219, USA;
| | - Jessica L. Gonzales
- California Animal Health and Food Safety Laboratory System, School of Veterinary Medicine, University of California Davis, San Bernardino, CA 92408, USA; (J.L.G.); (F.A.U.)
| | - Francisco A. Uzal
- California Animal Health and Food Safety Laboratory System, School of Veterinary Medicine, University of California Davis, San Bernardino, CA 92408, USA; (J.L.G.); (F.A.U.)
| | - Bruce A. McClane
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15219, USA;
| |
Collapse
|
6
|
Ni Z, Gong Z, Song L, Jia C, Zhang X. Adaptation strategies and functional transitions of microbial community in pyrene-contaminated soils promoted by lead with Pseudomonas veronii and its extracellular polymeric substances. CHEMOSPHERE 2024; 351:141139. [PMID: 38185422 DOI: 10.1016/j.chemosphere.2024.141139] [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: 07/18/2023] [Revised: 12/25/2023] [Accepted: 01/04/2024] [Indexed: 01/09/2024]
Abstract
Pyrene was designated as a remediation target in this study, and low contamination of lead (Pb) was set to induce heavy metal stress. Pseudomonas veronii and its extracellular polymeric substances (EPSs) were chosen for biofortification, with the aim of elucidating the structural, metabolic, and functional responses of soil microbial communities. Community analysis of soil microorganisms using high-throughput sequencing showed that the co-addition of P. veronii and EPSs resulted in an increase in relative abundance of phyla associated with pyrene degradation, and formed a symbiotic system dominated by Firmicutes and Proteobacteria, which involved in pyrene metabolism. Co-occurrence network analysis revealed that the module containing P. veronii was the only one exhibiting a positive correlation between bacterial abundance and pyrene removal, indicating the potential of bioaugmentation in enriching functional taxa. Biofortification also enhanced the abundance of functional gene linked to EPS production (biofilm formation-Pseudomonas aeruginosa) and pyrene degradation. Furthermore, 17 potential functional bacteria were screened out using random forest algorithm. Lead contamination further promoted the growth of Proteobacteria, intensified cooperative associations among bacteria, and increased the abundance of bacteria with positive correlation with pyrene degradation. The results offer novel perspectives on alterations in microbial communities resulting from the synergistic impact of heavy metal stress and biofortification.
Collapse
Affiliation(s)
- Zijun Ni
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Zongqiang Gong
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China.
| | - Lei Song
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Chunyun Jia
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China.
| | - Xiaorong Zhang
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China.
| |
Collapse
|
7
|
Zhang Y, Qiu X, Luo J, Li H, How SW, Wu D, He J, Cheng Z, Gao Y, Lu H. A review of the phosphorus removal of polyphosphate-accumulating organisms in natural and engineered systems. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:169103. [PMID: 38065508 DOI: 10.1016/j.scitotenv.2023.169103] [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: 09/17/2023] [Revised: 11/13/2023] [Accepted: 12/02/2023] [Indexed: 01/18/2024]
Abstract
Increasing eutrophication has led to a continuous deterioration of many aquatic ecosystems. Polyphosphate-accumulating organisms (PAOs) can provide insight into the human response to this challenge, as they initiate enhanced biological phosphorus removal (EBPR) through cyclical anaerobic phosphorus release and aerobic phosphorus uptake. Although the limiting environmental factors for PAO growth and phosphorus removal have been widely discussed, there remains a gap in the knowledge surrounding the differences in the type and phosphorus removal efficiencies of natural and engineered PAO systems. Furthermore, due to the limitations of PAOs in conventional wastewater treatment environments, there is an urgent need to find functional PAOs in extreme environments for better wastewater treatment. Therefore, it is necessary to explore the effects of extreme conditions on the phosphorus removal efficiency of PAOs as well as the types, sources, and characteristics of PAOs. In this paper, we summarize the response mechanisms of PAOs, denitrifying polyphosphate-accumulating organisms (D-PAOs), aerobic denitrifying polyphosphate-accumulating organisms (AD-PAOs), and sulfur-related PAOs (S-PAOs). The mechanism of nitrogen and phosphorus removal in PAOs is related to the coupling cycles of carbon, nitrogen, phosphorus, and sulfur. The genera of PAOs differ in natural and engineered systems, but PAOs have more diversity in aquatic environments and soils. Recent studies on the impact of several parameters (e.g., temperature, carbon source, pH, and dissolved oxygen) and extracellular polymer substances on the phosphorus removal efficiency of PAOs in natural and engineered systems are further discussed. Most of the PAOs screened under extreme conditions still had high phosphorus removal efficiencies (>80.0 %). These results provide a reference for searching for PAOs with different adaptations to achieve better wastewater treatment.
Collapse
Affiliation(s)
- Yan Zhang
- School of Environmental and Chemical Engineering, Foshan University, Foshan, Guangdong 528000, China
| | - Xiaoqing Qiu
- School of Environmental and Chemical Engineering, Foshan University, Foshan, Guangdong 528000, China
| | - Jiahao Luo
- School of Environmental and Chemical Engineering, Foshan University, Foshan, Guangdong 528000, China
| | - Huishi Li
- School of Environmental and Chemical Engineering, Foshan University, Foshan, Guangdong 528000, China
| | - Seow-Wah How
- Centre for Environmental and Energy Research, Ghent University Global Campus, Incheon 21985, Republic of Korea; Department of Green Chemistry and Technology, Ghent University, Centre for Advanced Process Technology for Urban REsource Recovery (CAPTURE), Ghent B9000, Belgium
| | - Di Wu
- Centre for Environmental and Energy Research, Ghent University Global Campus, Incheon 21985, Republic of Korea; Department of Green Chemistry and Technology, Ghent University, Centre for Advanced Process Technology for Urban REsource Recovery (CAPTURE), Ghent B9000, Belgium
| | - Juhua He
- School of Environmental and Chemical Engineering, Foshan University, Foshan, Guangdong 528000, China
| | - Zihang Cheng
- School of Environmental and Chemical Engineering, Foshan University, Foshan, Guangdong 528000, China
| | - Yunan Gao
- School of Environmental and Chemical Engineering, Foshan University, Foshan, Guangdong 528000, China
| | - Hui Lu
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China.
| |
Collapse
|
8
|
Rudakova NL, Sabirova AR, Khasanov DI, Danilova IV, Sharipova MR. Regulating Pathways of Bacillus pumilus Adamalysin-like Metalloendopeptidase Expression. Int J Mol Sci 2023; 25:62. [PMID: 38203233 PMCID: PMC10779165 DOI: 10.3390/ijms25010062] [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: 11/11/2023] [Revised: 12/14/2023] [Accepted: 12/17/2023] [Indexed: 01/12/2024] Open
Abstract
The minor secreted proteinase of B. pumilus 3-19 MprBp classified as the unique bacillary adamalysin-like enzyme of the metzincin clan. The functional role of this metalloproteinase in the bacilli cells is not clear. Analysis of the regulatory region of the mprBp gene showed the presence of potential binding sites to the transcription regulatory factors Spo0A (sporulation) and DegU (biodegradation). The study of mprBp activity in mutant strains of B. subtilis defective in regulatory proteins of the Spo- and Deg-systems showed that the mprBp gene is partially controlled by the Deg-system of signal transduction and independent from the Spo-system.
Collapse
Affiliation(s)
| | | | | | | | - Margarita R. Sharipova
- Institute of Fundamental Medicine, Kazan Federal University, Kremlevskaya St. 18, 420008 Kazan, Russia; (N.L.R.); (D.I.K.); (I.V.D.)
| |
Collapse
|
9
|
Dong J, Yang B, Wang H, Cao X, He F, Wang L. Reveal molecular mechanism on the effects of silver nanoparticles on nitrogen transformation and related functional microorganisms in an agricultural soil. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 904:166765. [PMID: 37660816 DOI: 10.1016/j.scitotenv.2023.166765] [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: 07/03/2023] [Revised: 08/29/2023] [Accepted: 08/31/2023] [Indexed: 09/05/2023]
Abstract
Silver nanoparticles (AgNPs) are widely present in aquatic and soil environment, raising significant concerns about their impacts on creatures in ecosystem. While the toxicity of AgNPs on microorganisms has been reported, their effects on biogeochemical processes and specific functional microorganisms remain relatively unexplored. In this study, a 28-day microcosmic experiment was conducted to investigate the dose-dependent effects of AgNPs (10 mg and 100 mg Ag kg-1 soil) on nitrogen transformation and functional microorganisms in agricultural soils. The molecular mechanisms were uncovered by examining change in functional microorganisms and metabolic pathways. To enable comparison, the toxicity of positive control with an equivalent Ag+ dose from CH3COOAg was also included. The results indicated that both AgNPs and CH3COOAg enhanced nitrogen fixation and nitrification, corresponding to increased relative abundances of associated functional genes. However, they inhibited denitrification via downregulating nirS, nirK, and nosZ genes as well as reducing nitrate and nitrite reductase activities. In contrast to high dose of AgNPs, low levels increased bacterial diversity. AgNPs and CH3COOAg altered the activities of associated metabolic pathways, resulting in the enrichment of specific taxa that demonstrated tolerance to Ag. At genus level, AgNPs increased the relative abundances of nitrogen-fixing Microvirga and Bacillus by 0.02 %-629.39 % and 14.44 %-30.10 %, respectively, compared with control group (CK). The abundances of denitrifying bacteria, such as Rhodoplanes, Pseudomonas, and Micromonospora, decreased by 19.03 % to 32.55 %, 24.73 % to 50.05 %, and 15.66 % to 76.06 %, respectively, compared to CK. CH3COOAg reduced bacterial network complexity, diminished the symbiosis mode compared to AgNPs. The prediction of genes involved in metabolic pathways related to membrane transporter and cell motility showed sensitive to AgNPs exposure in the soil. Further studies involving metabolomics are necessary to reveal the essential effects of AgNPs and CH3COOAg on biogeochemical cycle of elements in agricultural soil.
Collapse
Affiliation(s)
- Jinhao Dong
- School of Water Conservancy and Environment, University of Jinan, Jinan 250022, China
| | - Baoshan Yang
- School of Water Conservancy and Environment, University of Jinan, Jinan 250022, China; Shandong Provincial Engineering Technology Research Center for Ecological Carbon Sink and Capture Utilization, Jinan 250022, China.
| | - Hui Wang
- School of Water Conservancy and Environment, University of Jinan, Jinan 250022, China; Shandong Provincial Engineering Technology Research Center for Ecological Carbon Sink and Capture Utilization, Jinan 250022, China.
| | - Xinlei Cao
- School of Water Conservancy and Environment, University of Jinan, Jinan 250022, China
| | - Fei He
- Jinan Environmental Research Academy, Jinan 250098, China
| | - Lijiao Wang
- School of Water Conservancy and Environment, University of Jinan, Jinan 250022, China
| |
Collapse
|
10
|
Marini E, Olivença C, Ramalhete S, Aguirre AM, Ingle P, Melo MN, Antunes W, Minton NP, Hernandez G, Cordeiro TN, Sorg JA, Serrano M, Henriques AO. A sporulation signature protease is required for assembly of the spore surface layers, germination and host colonization in Clostridioides difficile. PLoS Pathog 2023; 19:e1011741. [PMID: 37956166 PMCID: PMC10681294 DOI: 10.1371/journal.ppat.1011741] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 11/27/2023] [Accepted: 10/09/2023] [Indexed: 11/15/2023] Open
Abstract
A genomic signature for endosporulation includes a gene coding for a protease, YabG, which in the model organism Bacillus subtilis is involved in assembly of the spore coat. We show that in the human pathogen Clostridioidesm difficile, YabG is critical for the assembly of the coat and exosporium layers of spores. YabG is produced during sporulation under the control of the mother cell-specific regulators σE and σK and associates with the spore surface layers. YabG shows an N-terminal SH3-like domain and a C-terminal domain that resembles single domain response regulators, such as CheY, yet is atypical in that the conserved phosphoryl-acceptor residue is absent. Instead, the CheY-like domain carries residues required for activity, including Cys207 and His161, the homologues of which form a catalytic diad in the B. subtilis protein, and also Asp162. The substitution of any of these residues by Ala, eliminates an auto-proteolytic activity as well as interdomain processing of CspBA, a reaction that releases the CspB protease, required for proper spore germination. An in-frame deletion of yabG or an allele coding for an inactive protein, yabGC207A, both cause misassemby of the coat and exosporium and the formation of spores that are more permeable to lysozyme and impaired in germination and host colonization. Furthermore, we show that YabG is required for the expression of at least two σK-dependent genes, cotA, coding for a coat protein, and cdeM, coding for a key determinant of exosporium assembly. Thus, YabG also impinges upon the genetic program of the mother cell possibly by eliminating a transcriptional repressor. Although this activity has not been described for the B. subtilis protein and most of the YabG substrates vary among sporeformers, the general role of the protease in the assembly of the spore surface is likely to be conserved across evolutionary distance.
Collapse
Affiliation(s)
- Eleonora Marini
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Avenida da República EAN, Oeiras, Portugal
| | - Carmen Olivença
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Avenida da República EAN, Oeiras, Portugal
| | - Sara Ramalhete
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Avenida da República EAN, Oeiras, Portugal
| | - Andrea Martinez Aguirre
- Texas A&M University, Department of Biology, College Station, Texas, United States of America
| | - Patrick Ingle
- Clostridia Research Group, BBSRC/EPSRC Synthetic Biology Research Centre (SBRC), School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Manuel N Melo
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Avenida da República EAN, Oeiras, Portugal
| | - Wilson Antunes
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Avenida da República EAN, Oeiras, Portugal
| | - Nigel P Minton
- Clostridia Research Group, BBSRC/EPSRC Synthetic Biology Research Centre (SBRC), School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Guillem Hernandez
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Avenida da República EAN, Oeiras, Portugal
| | - Tiago N Cordeiro
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Avenida da República EAN, Oeiras, Portugal
| | - Joseph A Sorg
- Texas A&M University, Department of Biology, College Station, Texas, United States of America
| | - Mónica Serrano
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Avenida da República EAN, Oeiras, Portugal
| | - Adriano O Henriques
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Avenida da República EAN, Oeiras, Portugal
| |
Collapse
|
11
|
Lablaine A, Chamot S, Serrano M, Billaudeau C, Bornard I, Carballido-López R, Carlin F, Henriques AO, Broussolle V. A new fluorescence-based approach for direct visualization of coat formation during sporulation in Bacillus cereus. Sci Rep 2023; 13:15136. [PMID: 37704668 PMCID: PMC10499802 DOI: 10.1038/s41598-023-42143-9] [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: 05/12/2023] [Accepted: 09/06/2023] [Indexed: 09/15/2023] Open
Abstract
The human pathogenic bacteria Bacillus cereus, Bacillus anthracis and the entomopathogenic Bacillus thuringiensis form spores encased in a protein coat surrounded by a balloon-like exosporium. These structures mediate spore interactions with its environment, including the host immune system, control the transit of molecules that trigger germination and thus are essential for the spore life cycle. Formation of the coat and exosporium has been traditionally visualized by transmission electronic microscopy on fixed cells. Recently, we showed that assembly of the exosporium can be directly observed in live B. cereus cells by super resolution-structured illumination microscopy (SR-SIM) using the membrane MitoTrackerGreen (MTG) dye. Here, we demonstrate that the different steps of coat formation can also be visualized by SR-SIM using MTG and SNAP-cell TMR-star dyes during B. cereus sporulation. We used these markers to characterize a subpopulation of engulfment-defective B. cereus cells that develops at a suboptimal sporulation temperature. Importantly, we predicted and confirmed that synthesis and accumulation of coat material, as well as synthesis of the σK-dependent protein BxpB, occur in cells arrested during engulfment. These results suggest that, unlike the well-studied model organism Bacillus subtilis, the activity of σK is not strictly linked to the state of forespore development in B. cereus.
Collapse
Affiliation(s)
- Armand Lablaine
- INRAE, Avignon Université, UMR SQPOV, 84000, Avignon, France
- MICALIS Institute, INRAE, AgroParisTech, Université Paris-Saclay, 78350, Jouy-en-Josas, France
| | | | - Mónica Serrano
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, 2780-157, Oeiras, Portugal
| | - Cyrille Billaudeau
- MICALIS Institute, INRAE, AgroParisTech, Université Paris-Saclay, 78350, Jouy-en-Josas, France
| | | | - Rut Carballido-López
- MICALIS Institute, INRAE, AgroParisTech, Université Paris-Saclay, 78350, Jouy-en-Josas, France
| | - Frédéric Carlin
- INRAE, Avignon Université, UMR SQPOV, 84000, Avignon, France
| | - Adriano O Henriques
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, 2780-157, Oeiras, Portugal
| | | |
Collapse
|
12
|
Liu Y, Chen S, Wang J, Shao B, Fang J, Cao J. The Phylogeny, Metabolic Potentials, and Environmental Adaptation of an Anaerobe, Abyssisolibacter sp. M8S5, Isolated from Cold Seep Sediments of the South China Sea. Microorganisms 2023; 11:2156. [PMID: 37764000 PMCID: PMC10536192 DOI: 10.3390/microorganisms11092156] [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: 08/08/2023] [Revised: 08/17/2023] [Accepted: 08/24/2023] [Indexed: 09/29/2023] Open
Abstract
Bacillota are widely distributed in various environments, owing to their versatile metabolic capabilities and remarkable adaptation strategies. Recent studies reported that Bacillota species were highly enriched in cold seep sediments, but their metabolic capabilities, ecological functions, and adaption mechanisms in the cold seep habitats remained obscure. In this study, we conducted a systematic analysis of the complete genome of a novel Bacillota bacterium strain M8S5, which we isolated from cold seep sediments of the South China Sea at a depth of 1151 m. Phylogenetically, strain M8S5 was affiliated with the genus Abyssisolibacter within the phylum Bacillota. Metabolically, M8S5 is predicted to utilize various carbon and nitrogen sources, including chitin, cellulose, peptide/oligopeptide, amino acids, ethanolamine, and spermidine/putrescine. The pathways of histidine and proline biosynthesis were largely incomplete in strain M8S5, implying that its survival strictly depends on histidine- and proline-related organic matter enriched in the cold seep ecosystems. On the other hand, strain M8S5 contained the genes encoding a variety of extracellular peptidases, e.g., the S8, S11, and C25 families, suggesting its capabilities for extracellular protein degradation. Moreover, we identified a series of anaerobic respiratory genes, such as glycine reductase genes, in strain M8S5, which may allow it to survive in the anaerobic sediments of cold seep environments. Many genes associated with osmoprotectants (e.g., glycine betaine, proline, and trehalose), transporters, molecular chaperones, and reactive oxygen species-scavenging proteins as well as spore formation may contribute to its high-pressure and low-temperature adaptations. These findings regarding the versatile metabolic potentials and multiple adaptation strategies of strain M8S5 will expand our understanding of the Bacillota species in cold seep sediments and their potential roles in the biogeochemical cycling of deep marine ecosystems.
Collapse
Affiliation(s)
- Ying Liu
- Shanghai Engineering Research Center of Hadal Science and Technology, College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, China; (Y.L.); (J.W.); (B.S.)
- The Guangxi Key Laboratory of Beibu Gulf Marine Biodiversity Conservation, College of Marine Sciences, Beibu Gulf University, Qinzhou 535000, China
| | - Songze Chen
- Shenzhen Ecological and Environmental Monitoring Center of Guangdong Province, Shenzhen 518049, China;
| | - Jiahua Wang
- Shanghai Engineering Research Center of Hadal Science and Technology, College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, China; (Y.L.); (J.W.); (B.S.)
| | - Baoying Shao
- Shanghai Engineering Research Center of Hadal Science and Technology, College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, China; (Y.L.); (J.W.); (B.S.)
| | - Jiasong Fang
- Shanghai Engineering Research Center of Hadal Science and Technology, College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, China; (Y.L.); (J.W.); (B.S.)
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266000, China
| | - Junwei Cao
- Shanghai Engineering Research Center of Hadal Science and Technology, College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, China; (Y.L.); (J.W.); (B.S.)
| |
Collapse
|
13
|
Guerrero M. GG. Sporulation, Structure Assembly, and Germination in the Soil Bacterium Bacillus thuringiensis: Survival and Success in the Environment and the Insect Host. MICROBIOLOGY RESEARCH 2023. [DOI: 10.3390/microbiolres14020035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/08/2023] Open
Abstract
Bacillus thuringiensis (Bt) is a rod-shaped, Gram-positive soil bacterium that belongs to the phylum Firmicutes and the genus Bacillus. It is a spore-forming bacterium. During sporulation, it produces a wide range of crystalline proteins that are toxic to different orders of insects. Sporulation, structure assembly, and germination are essential stages in the cell cycle of B. thuringiensis. The majority of studies on these issues have focused on the model organism Bacillus subtilis, followed by Bacillus cereus and Bacillus anthracis. The machinery for sporulation and germination extrapolated to B. thuringiensis. However, in the light of recent findings concerning the role of the sporulation proteins (SPoVS), the germination receptors (Gr), and the cortical enzymes in Bt, the theory strengthened that conservation in sporulation, structure assembly, and germination programs drive the survival and success of B. thuringiensis in the environment and the insect host. In the present minireview, the latter pinpointed and reviewed.
Collapse
Affiliation(s)
- Gloria G. Guerrero M.
- Unidad Académica de Ciencias Biológicas, Laboratorio de Immunobiología, Universidad Autónoma de Zacatecas, Av. Preparatoria S/N, Col. Agronomicas, Zacatecas 98066, Mexico
| |
Collapse
|
14
|
Tang SK, Zhi XY, Zhang Y, Makarova KS, Liu BB, Zheng GS, Zhang ZP, Zheng HJ, Wolf YI, Zhao YR, Jiang SH, Chen XM, Li EY, Zhang T, Chen PR, Feng YZ, Xiang MX, Lin ZQ, Shi JH, Chang C, Zhang X, Li R, Lou K, Wang Y, Chang L, Yin M, Yang LL, Gao HY, Zhang ZK, Tao TS, Guan TW, He FC, Lu YH, Cui HL, Koonin EV, Zhao GP, Xu P. Cellular differentiation into hyphae and spores in halophilic archaea. Nat Commun 2023; 14:1827. [PMID: 37005419 PMCID: PMC10067837 DOI: 10.1038/s41467-023-37389-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 03/14/2023] [Indexed: 04/04/2023] Open
Abstract
Several groups of bacteria have complex life cycles involving cellular differentiation and multicellular structures. For example, actinobacteria of the genus Streptomyces form multicellular vegetative hyphae, aerial hyphae, and spores. However, similar life cycles have not yet been described for archaea. Here, we show that several haloarchaea of the family Halobacteriaceae display a life cycle resembling that of Streptomyces bacteria. Strain YIM 93972 (isolated from a salt marsh) undergoes cellular differentiation into mycelia and spores. Other closely related strains are also able to form mycelia, and comparative genomic analyses point to gene signatures (apparent gain or loss of certain genes) that are shared by members of this clade within the Halobacteriaceae. Genomic, transcriptomic and proteomic analyses of non-differentiating mutants suggest that a Cdc48-family ATPase might be involved in cellular differentiation in strain YIM 93972. Additionally, a gene encoding a putative oligopeptide transporter from YIM 93972 can restore the ability to form hyphae in a Streptomyces coelicolor mutant that carries a deletion in a homologous gene cluster (bldKA-bldKE), suggesting functional equivalence. We propose strain YIM 93972 as representative of a new species in a new genus within the family Halobacteriaceae, for which the name Actinoarchaeum halophilum gen. nov., sp. nov. is herewith proposed. Our demonstration of a complex life cycle in a group of haloarchaea adds a new dimension to our understanding of the biological diversity and environmental adaptation of archaea.
Collapse
Affiliation(s)
- Shu-Kun Tang
- Yunnan Institute of Microbiology, Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming, 650091, China.
| | - Xiao-Yang Zhi
- Yunnan Institute of Microbiology, Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming, 650091, China
| | - Yao Zhang
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences Beijing, Research Unit of Proteomics & Research and Development of New Drug,Research Unit of Proteomics Driven Cancer Precision Medicine, Chinese Academy of Medical Sciences, Institute of Lifeomics, Beijing, 102206, China
| | - Kira S Makarova
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, 8600 Rockville Pike, Bethesda, MD, 20894, USA
| | - Bing-Bing Liu
- Yunnan Institute of Microbiology, Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming, 650091, China
- Henan Key Laboratory of Industrial Microbial Resources and Fermentation Technology, College of Biological and Chemical Engineering, Nanyang Institute of Technology, Nanyang, 473004, China
| | - Guo-Song Zheng
- College of Life Sciences, Shanghai Normal University, Shanghai, 200234, China
| | - Zhen-Peng Zhang
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences Beijing, Research Unit of Proteomics & Research and Development of New Drug,Research Unit of Proteomics Driven Cancer Precision Medicine, Chinese Academy of Medical Sciences, Institute of Lifeomics, Beijing, 102206, China
| | - Hua-Jun Zheng
- Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center at Shanghai and Shanghai Institute for Biomedical and Pharmaceutical Technologies, Shanghai, 201203, China
| | - Yuri I Wolf
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, 8600 Rockville Pike, Bethesda, MD, 20894, USA
| | - Yu-Rong Zhao
- Yunnan Institute of Microbiology, Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming, 650091, China
| | - Song-Hao Jiang
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences Beijing, Research Unit of Proteomics & Research and Development of New Drug,Research Unit of Proteomics Driven Cancer Precision Medicine, Chinese Academy of Medical Sciences, Institute of Lifeomics, Beijing, 102206, China
- Hebei Province Key Lab of Research and Application on Microbial Diversity, College of Life Sciences, Hebei University, Hebei, 071002, China
| | - Xi-Ming Chen
- Key Laboratory of Desert and Desertification, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - En-Yuan Li
- Yunnan Institute of Microbiology, Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming, 650091, China
| | - Tao Zhang
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences Beijing, Research Unit of Proteomics & Research and Development of New Drug,Research Unit of Proteomics Driven Cancer Precision Medicine, Chinese Academy of Medical Sciences, Institute of Lifeomics, Beijing, 102206, China
| | - Pei-Ru Chen
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences Beijing, Research Unit of Proteomics & Research and Development of New Drug,Research Unit of Proteomics Driven Cancer Precision Medicine, Chinese Academy of Medical Sciences, Institute of Lifeomics, Beijing, 102206, China
- Hebei Province Key Lab of Research and Application on Microbial Diversity, College of Life Sciences, Hebei University, Hebei, 071002, China
| | - Yu-Zhou Feng
- Yunnan Institute of Microbiology, Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming, 650091, China
| | - Ming-Xian Xiang
- Yunnan Institute of Microbiology, Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming, 650091, China
| | - Zhi-Qian Lin
- Yunnan Institute of Microbiology, Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming, 650091, China
| | - Jia-Hui Shi
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences Beijing, Research Unit of Proteomics & Research and Development of New Drug,Research Unit of Proteomics Driven Cancer Precision Medicine, Chinese Academy of Medical Sciences, Institute of Lifeomics, Beijing, 102206, China
- Hebei Province Key Lab of Research and Application on Microbial Diversity, College of Life Sciences, Hebei University, Hebei, 071002, China
| | - Cheng Chang
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences Beijing, Research Unit of Proteomics & Research and Development of New Drug,Research Unit of Proteomics Driven Cancer Precision Medicine, Chinese Academy of Medical Sciences, Institute of Lifeomics, Beijing, 102206, China
| | - Xue Zhang
- Henan Key Laboratory of Industrial Microbial Resources and Fermentation Technology, College of Biological and Chemical Engineering, Nanyang Institute of Technology, Nanyang, 473004, China
| | - Rui Li
- Yunnan Institute of Microbiology, Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming, 650091, China
| | - Kai Lou
- Xinjiang Institute of Microbiology, Xinjiang Academy of Agricultural Science, Urumqi, 830091, China
| | - Yun Wang
- Xinjiang Institute of Microbiology, Xinjiang Academy of Agricultural Science, Urumqi, 830091, China
| | - Lei Chang
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences Beijing, Research Unit of Proteomics & Research and Development of New Drug,Research Unit of Proteomics Driven Cancer Precision Medicine, Chinese Academy of Medical Sciences, Institute of Lifeomics, Beijing, 102206, China
| | - Min Yin
- Yunnan Institute of Microbiology, Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming, 650091, China
| | - Ling-Ling Yang
- Yunnan Institute of Microbiology, Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming, 650091, China
| | - Hui-Ying Gao
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences Beijing, Research Unit of Proteomics & Research and Development of New Drug,Research Unit of Proteomics Driven Cancer Precision Medicine, Chinese Academy of Medical Sciences, Institute of Lifeomics, Beijing, 102206, China
| | - Zhong-Kai Zhang
- Biotechnology and Genetic Germplasm Resources Research Institute, Yunnan Academy of Agricultural Sciences, Kunming, 650205, China
| | - Tian-Shen Tao
- Department of Microbiology, Key Laboratory of Combinatorial Biosynthesis and Drug Discovery of Ministry of Education, School of Pharmaceutical Sciences, Wuhan University, Wuhan, 430072, China
| | - Tong-Wei Guan
- College of Food and Biological Engineering, Xihua University, Chengdu, 610039, China
| | - Fu-Chu He
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences Beijing, Research Unit of Proteomics & Research and Development of New Drug,Research Unit of Proteomics Driven Cancer Precision Medicine, Chinese Academy of Medical Sciences, Institute of Lifeomics, Beijing, 102206, China
| | - Yin-Hua Lu
- College of Life Sciences, Shanghai Normal University, Shanghai, 200234, China
| | - Heng-Lin Cui
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, 212013, China
| | - Eugene V Koonin
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, 8600 Rockville Pike, Bethesda, MD, 20894, USA.
| | - Guo-Ping Zhao
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences and Department of Microbiology and Microbial Engineering, School of Life Sciences, Fudan University, Shanghai, 200032, China.
| | - Ping Xu
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences Beijing, Research Unit of Proteomics & Research and Development of New Drug,Research Unit of Proteomics Driven Cancer Precision Medicine, Chinese Academy of Medical Sciences, Institute of Lifeomics, Beijing, 102206, China.
- Hebei Province Key Lab of Research and Application on Microbial Diversity, College of Life Sciences, Hebei University, Hebei, 071002, China.
- Department of Microbiology, Key Laboratory of Combinatorial Biosynthesis and Drug Discovery of Ministry of Education, School of Pharmaceutical Sciences, Wuhan University, Wuhan, 430072, China.
- Guizhou University, School of Medicine, Guiyang, 550025, China.
- State Key Laboratory of Dampness Syndrome of Chinese Medicine, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, 510120, China.
| |
Collapse
|
15
|
Li C, Du X, Liu ZH, Li BZ, Meng X, Zhao J, Zhao ZM, Ragauskas AJ. Steam explosion pretreatment coupling high-temperature short-time sterilization facilitating cellulose degradation and sporulation-regulatory gene expression in high-solid fermentation. Int J Biol Macromol 2023; 232:123475. [PMID: 36720325 DOI: 10.1016/j.ijbiomac.2023.123475] [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: 07/29/2022] [Revised: 01/21/2023] [Accepted: 01/25/2023] [Indexed: 01/29/2023]
Abstract
Steam explosion coupling high-temperature short-time sterilization (SE-HTST) was exploited to modify cellulosic biomass medium properties and promote high-solid fermentation (HSF). Biomass characterization analysis showed that SE-HTST enlarged microstructural pores and cavities in solid media, providing more effective space for microbial growth. Meanwhile, SE-HTST helped to release glucose from the cellulose with 35.8 ± 4.5, 20.0 ± 2.3, and 12.3 ± 5.7 mg glucose/g dry medium at 24, 48, and 72 h of fermentation, which were 3.1, 2.3, and 1.5 times higher than that in medium from conventional thermal sterilization (CTS), respectively. SE-HTST increased the viable cell and spore number of Bacillus subtilis by 1.8 and 1.6 times at 72 h of fermentation compared to CTS. Moreover, the expressions of master transcriptional gene spo0A and the early sigma factors of sigF and sigE genes gradually increased in the SE-HTST medium, showing enhanced sporulation in HSF. Therefore, SE-HTST is an effective strategy for facilitating cellulose degradation, improving glucose nutrients in biomass medium, and promoting sporulation-regulatory gene expression during high-solid fermentation, which enhances the production of microbial ecological agents using B. subtilis significantly.
Collapse
Affiliation(s)
- Chonglei Li
- School of Ecology and Environment, Inner Mongolia Key Laboratory of Environmental Pollution Control & Wastes Reuse, Inner Mongolia University, Hohhot 010021, China
| | - Xiaoyu Du
- School of Ecology and Environment, Inner Mongolia Key Laboratory of Environmental Pollution Control & Wastes Reuse, Inner Mongolia University, Hohhot 010021, China
| | - Zhi-Hua Liu
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering, Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
| | - Bing-Zhi Li
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering, Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
| | - Xianzhi Meng
- Department of Chemical & Biomolecular Engineering, University of Tennessee, Knoxville, TN 37996, United States
| | - Ji Zhao
- School of Ecology and Environment, Inner Mongolia Key Laboratory of Environmental Pollution Control & Wastes Reuse, Inner Mongolia University, Hohhot 010021, China
| | - Zhi-Min Zhao
- School of Ecology and Environment, Inner Mongolia Key Laboratory of Environmental Pollution Control & Wastes Reuse, Inner Mongolia University, Hohhot 010021, China; Department of Chemical & Biomolecular Engineering, University of Tennessee, Knoxville, TN 37996, United States; Joint Institute of Biological Sciences, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States.
| | - Arthur J Ragauskas
- Department of Chemical & Biomolecular Engineering, University of Tennessee, Knoxville, TN 37996, United States; Joint Institute of Biological Sciences, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States; Center for Renewable Carbon, Department of Forestry, Wildlife, and Fisheries, University of Tennessee Institute of Agriculture, Knoxville, TN 37996, United States.
| |
Collapse
|
16
|
Romero-Rodríguez A, Ruiz-Villafán B, Martínez-de la Peña CF, Sánchez S. Targeting the Impossible: A Review of New Strategies against Endospores. Antibiotics (Basel) 2023; 12:antibiotics12020248. [PMID: 36830159 PMCID: PMC9951900 DOI: 10.3390/antibiotics12020248] [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: 12/05/2022] [Revised: 01/13/2023] [Accepted: 01/20/2023] [Indexed: 01/27/2023] Open
Abstract
Endospore-forming bacteria are ubiquitous, and their endospores can be present in food, in domestic animals, and on contaminated surfaces. Many spore-forming bacteria have been used in biotechnological applications, while others are human pathogens responsible for a wide range of critical clinical infections. Due to their resistant properties, it is challenging to eliminate spores and avoid the reactivation of latent spores that may lead to active infections. Furthermore, endospores play an essential role in the survival, transmission, and pathogenesis of some harmful strains that put human and animal health at risk. Thus, different methods have been applied for their eradication. Nevertheless, natural products are still a significant source for discovering and developing new antibiotics. Moreover, targeting the spore for clinical pathogens such as Clostridioides difficile is essential to disease prevention and therapeutics. These strategies could directly aim at the structural components of the spore or their germination process. This work summarizes the current advances in upcoming strategies and the development of natural products against endospores. This review also intends to highlight future perspectives in research and applications.
Collapse
Affiliation(s)
- Alba Romero-Rodríguez
- Departamento de Biología Molecular y Biotecnología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad de México 04510, Mexico
- Correspondence:
| | - Beatriz Ruiz-Villafán
- Departamento de Biología Molecular y Biotecnología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad de México 04510, Mexico
| | - Claudia Fabiola Martínez-de la Peña
- Centro de Investigaciones en Ciencias Microbiológicas, Instituto de Ciencias, Benemérita Universidad Autónoma de Puebla, Puebla 72592, Mexico
| | - Sergio Sánchez
- Departamento de Biología Molecular y Biotecnología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad de México 04510, Mexico
| |
Collapse
|
17
|
Zhu Y, Liu Y, Chang H, Yang H, Zhang W, Zhang Y, Sun H. Deciphering the microbial community structures and functions of wastewater treatment at high-altitude area. Front Bioeng Biotechnol 2023; 11:1107633. [PMID: 36923457 PMCID: PMC10009103 DOI: 10.3389/fbioe.2023.1107633] [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: 11/25/2022] [Accepted: 01/30/2023] [Indexed: 03/02/2023] Open
Abstract
Introduction: The proper operation of wastewater treatment plants is a key factor in maintaining a stable river and lake environment. Low purification efficiency in winter is a common problem in high-altitude wastewater treatment plants (WWTPs), and analysis of the microbial community involved in the sewage treatment process at high-altitude can provide valuable references for improving this problem. Methods: In this study, the bacterial communities of high- and low-altitude WWTPs were investigated using Illumina high-throughput sequencing (HTS). The interaction between microbial community and environmental variables were explored by co-occurrence correlation network. Results: At genus level, Thauera (5.2%), unclassified_Rhodocyclaceae (3.0%), Dokdonella (2.5%), and Ferribacterium (2.5%) were the dominant genera in high-altitude group. The abundance of nitrogen and phosphorus removal bacteria were higher in high-altitude group (10.2% and 1.3%, respectively) than in low-altitude group (5.4% and 0.6%, respectively). Redundancy analysis (RDA) and co-occurrence network analysis showed that altitude, ultraviolet index (UVI), pH, dissolved oxygen (DO) and total nitrogen (TN) were the dominated environmental factors (p < 0.05) affecting microbial community assembly, and these five variables explained 21.4%, 20.3%, 16.9%, 11.5%, and 8.2% of the bacterial assembly of AS communities. Discussion: The community diversity of high-altitude group was lower than that of low-altitude group, and WWTPs of high-altitude aeras had a unique microbial community structure. Low temperature and strong UVI are pivotal factors contributing to the reduced diversity of activated sludge microbial communities at high-altitudes.
Collapse
Affiliation(s)
- Yuliang Zhu
- School of Environmental and Material Engineering, Yantai University, Yantai, China.,School of Civil Engineering, Yantai University, Yantai, Shandong, China
| | - Yucan Liu
- School of Civil Engineering, Yantai University, Yantai, Shandong, China
| | - Huanhuan Chang
- School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou, China
| | - Hao Yang
- School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou, China
| | - Wei Zhang
- School of Environmental and Material Engineering, Yantai University, Yantai, China
| | - Yanxiang Zhang
- School of Environmental and Material Engineering, Yantai University, Yantai, China
| | - Hongwei Sun
- School of Environmental and Material Engineering, Yantai University, Yantai, China
| |
Collapse
|
18
|
Sun Q, Zhu G. Deciphering the effects of antibiotics on nitrogen removal and bacterial communities of autotrophic denitrification systems in a three-dimensional biofilm electrode reactor. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 315:120476. [PMID: 36272603 DOI: 10.1016/j.envpol.2022.120476] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 10/12/2022] [Accepted: 10/16/2022] [Indexed: 06/16/2023]
Abstract
In this study, three-dimensional biofilm electrode reactors (3D-BERs) were constructed, and the effects of metronidazole (MNZ) on the nitrogen removal performance and bacterial communities of autotrophic denitrification systems were evaluated. The results showed that nitrogen removal decreased slightly as the MNZ concentration increased. Specifically, nitrate-nitrogen removal efficiency decreased from 97.98% to 89.39%, 86.93%, 82.64%, and 82.77% within 12 h after the addition of 1, 3, 5, and 10 mg/L MNZ, respectively. The 3D-BERs showed excellent MNZ degradation ability, especially at a concentration of 10 mg/L. The MNZ removal efficiency could be as high as 94.38% within 6 h, and the average removal rate increased as the MNZ concentration increased. High-throughput sequencing results showed significant changes in the bacterial community under different MNZ concentrations. As the antibiotic concentration increased, the relative abundances of Hydrogenophaga and Silanimonas increased, from only 0.09% and 0.01% without antibiotics to 3.55% and 2.35%, respectively, at an antibiotic concentration of 10 mg/L. Changes in antibiotic concentration altered the abundances of genes involved in nitrogen metabolism. Redundancy analysis showed that MNZ removal efficiency was positively correlated with SBR1031, SC-I-84, Hydrogenophaga, Silanimonas and Denitratesoma, whereas the removal efficiencies of nitrate-nitrogen and total nitrogen were negatively correlated with these genera. The results of this study provide a theoretical basis for studying the toxic effects of antibiotics on the denitrification process and also provide guidance for the control of antibiotics and nitrogen pollution in ecosystems.
Collapse
Affiliation(s)
- Qi Sun
- School of Energy and Environment, Southeast University, Nanjing, Jiangsu, 210096, China.
| | - Guangcan Zhu
- School of Energy and Environment, Southeast University, Nanjing, Jiangsu, 210096, China; Key Laboratory of Water Pollution Control and Ecological Restoration of Xizang, National Ethnic Affairs Commission, Xizang Minzu University, Xianyang, Shaanxi, 712082, China.
| |
Collapse
|
19
|
Du M, Wang J, Jin Y, Fan J, Zan S, Li Z. Response mechanism of microbial community during anaerobic biotransformation of marine toxin domoic acid. ENVIRONMENTAL RESEARCH 2022; 215:114410. [PMID: 36154856 DOI: 10.1016/j.envres.2022.114410] [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: 07/01/2022] [Revised: 09/12/2022] [Accepted: 09/19/2022] [Indexed: 06/16/2023]
Abstract
Domoic acid (DA) is a potent neurotoxin produced by toxigenic Pseudo-nitzschia blooms and quickly transfers to the benthic anaerobic environment by marine snow particles. DA anaerobic biotransformation is driven by microbial interactions, in which trace amounts of DA can cause physiological stress in marine microorganisms. However, the underlying response mechanisms of microbial community to DA stress remain unclear. In this study, we utilized an anaerobic marine DA-degrading consortium GLY (using glycine as co-substrate) to systematically investigate the global response mechanisms of microbial community during DA anaerobic biotransformation.16S rRNA gene sequencing and metatranscriptomic analyses were applied to measure microbial community structure, function and metabolic responses. Results showed that DA stress markedly changed the composition of main species, with increased levels of Firmicutes and decreased levels of Proteobacteria, Cyanobacteria, Bacteroidetes and Actinobacteria. Several genera of tolerated bacteria (Bacillus and Solibacillus) were increased, while, Stenotrophomonas, Sphingomonas and Acinetobacter were decreased. Metatranscriptomic analyses indicated that DA stimulated the expression of quorum sensing, extracellular polymeric substance (EPS) production, sporulation, membrane transporters, bacterial chemotaxis, flagellar assembly and ribosome protection in community, promoting bacterial adaptation ability under DA stress. Moreover, amino acid metabolism, carbohydrate metabolism and lipid metabolism were modulated during DA anaerobic biotransformation to reduce metabolic burden, increase metabolic demands for EPS production and DA degradation. This study provides the new insights into response of microbial community to DA stress and its potential impact on benthic microorganisms in marine environments.
Collapse
Affiliation(s)
- Miaomiao Du
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, PR China
| | - Jing Wang
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, PR China.
| | - Yuan Jin
- Marine Ecology Department, National Marine Environmental Monitoring Center, Dalian, 116023, PR China
| | - Jingfeng Fan
- Marine Ecology Department, National Marine Environmental Monitoring Center, Dalian, 116023, PR China
| | - Shuaijun Zan
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, PR China
| | - Zelong Li
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, PR China
| |
Collapse
|
20
|
Li C, Zhao K, Ma L, Zhao J, Zhao ZM. Effects of drying strategies on sporulation and titer of microbial ecological agents with Bacillus subtilis. Front Nutr 2022; 9:1025248. [PMID: 36238457 PMCID: PMC9551345 DOI: 10.3389/fnut.2022.1025248] [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: 08/22/2022] [Accepted: 09/06/2022] [Indexed: 11/23/2022] Open
Abstract
Drying operation is beneficial to the preservation and transportation of microbial ecological agents. In this study, drying kinetics and water distribution variations in solid biomass medium during hot air drying (HAD) and vacuum freeze drying (VFD) were systematically investigated. Meanwhile, the effects of different drying strategies on the sporulation of Bacillus subtilis and the titer of microbial ecological agents were compared. The results showed that both HAD and VFD induced rapid water removal from the solid biomass medium. VFD retained bound water and maintained the porous structure of the solid medium. Both HAD and VFD induced sporulation. The expression level of sporulation-regulatory genes spo0A, sigF, and sigE followed the order 80°C-HAD > 60°C-HAD > VFD. The spore number in the medium after 80°C-HAD drying for 6 h was 0.72 × 1010/g dry medium, which was 9.1 and 12.5% larger than that of the medium with 60°C-HAD and VFD, respectively. Therefore, 80°C-HAD is an effective drying strategy for promoting sporulation, which improves the titer of microbial ecological agents with B. subtilis.
Collapse
Affiliation(s)
- Chonglei Li
- Inner Mongolia Key Laboratory of Environmental Pollution Control and Wastes Reuse, School of Ecology and Environment, Inner Mongolia University, Hohhot, China
- Key Laboratory of Ecology and Resource Use of the Mongolian Plateau (Ministry of Education), Inner Mongolia University, Hohhot, China
| | - Kai Zhao
- Inner Mongolia Key Laboratory of Environmental Pollution Control and Wastes Reuse, School of Ecology and Environment, Inner Mongolia University, Hohhot, China
- Key Laboratory of Ecology and Resource Use of the Mongolian Plateau (Ministry of Education), Inner Mongolia University, Hohhot, China
| | - Litong Ma
- Inner Mongolia Engineering Research Center of Comprehensive Utilization of Bio-coal Chemical Industry, School of Chemistry and Chemical Engineering, Inner Mongolia University of Science and Technology, Baotou, China
| | - Ji Zhao
- Inner Mongolia Key Laboratory of Environmental Pollution Control and Wastes Reuse, School of Ecology and Environment, Inner Mongolia University, Hohhot, China
| | - Zhi-Min Zhao
- Inner Mongolia Key Laboratory of Environmental Pollution Control and Wastes Reuse, School of Ecology and Environment, Inner Mongolia University, Hohhot, China
- Key Laboratory of Ecology and Resource Use of the Mongolian Plateau (Ministry of Education), Inner Mongolia University, Hohhot, China
- *Correspondence: Zhi-Min Zhao
| |
Collapse
|
21
|
Response Regulator CD1688 Is a Negative Modulator of Sporulation in Clostridioides difficile. J Bacteriol 2022; 204:e0013022. [PMID: 35852332 PMCID: PMC9380558 DOI: 10.1128/jb.00130-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Two-component signal transduction systems (TCSs), consisting of a sensor histidine kinase (HK) and a response regulator (RR), sense environmental stimuli and then modulate cellular responses, typically through changes in gene expression. Our previous work identified the DNA binding motif of CD1586, an RR implicated in Clostridioides difficile strain R20291 sporulation. To determine the role of this RR in the sporulation pathway in C. difficile, we generated a deletion strain of cd1688 in the historical 630 strain, the homolog of cd1586. The C. difficile Δcd1688 strain exhibited a hypersporulation phenotype, suggesting that CD1688 negatively regulates sporulation. Complementation of the C. difficile Δcd1688 strain restored sporulation. In contrast, a nonphosphorylatable copy of cd1688 did not restore sporulation to wild-type (WT) levels, indicating that CD1688 must be phosphorylated to properly modulate sporulation. Expression of the master regulator spo0A, the sporulation-specific sigma factors sigF, sigE, sigG, and sigK, and a signaling protein encoded by spoIIR was increased in the C. difficile Δcd1688 strain compared to WT. In line with the increased spoIIR expression, we detected an increase in mature SigE at an earlier time point, which arises from SpoIIR-mediated processing of pro-SigE. Taken together, our data suggest that CD1688 is a novel negative modulator of sporulation in C. difficile and contributes to mediating progression through the spore developmental pathway. These results add to our growing understanding of the complex regulatory events involved in C. difficile sporulation, insight that could be exploited for novel therapeutic development. IMPORTANCEClostridioides difficile causes severe gastrointestinal illness and is a leading cause of nosocomial infections in the United States. This pathogen produces metabolically dormant spores that are the major vehicle of transmission between hosts. The sporulation pathway involves an intricate regulatory network that controls a succession of morphological changes necessary to produce spores. The environmental signals inducing the sporulation pathway are not well understood in C. difficile. This work identified a response regulator, CD1688, that, when deleted, led to a hypersporulation phenotype, indicating that it typically acts to repress sporulation. Improving our understanding of the regulatory mechanisms modulating sporulation in C. difficile could provide novel strategies to eliminate or reduce spore production, thus decreasing transmission and disease relapse.
Collapse
|
22
|
Yi M, Zhang L, Li Y, Qian Y. Structural, metabolic, and functional characteristics of soil microbial communities in response to benzo[a]pyrene stress. JOURNAL OF HAZARDOUS MATERIALS 2022; 431:128632. [PMID: 35278957 DOI: 10.1016/j.jhazmat.2022.128632] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 03/02/2022] [Accepted: 03/02/2022] [Indexed: 05/11/2023]
Abstract
Understanding the characteristics of soil microbes responding to benzo[a]pyrene (BaP) helps to deepen the knowledge of the risks of BaP to soil ecosystem. In this study, the structural, metabolic, and functional responses of soil microbial communities to BaP (8.11 mg kg-1) were investigated. Analysis of microbial community structure based on 16 S rRNA and ITS gene sequencing indicated that BaP addition enriched microbes associated with aromatic compound degradation (Sphingomonas, Bacilli, Fusarium) and oligotrophs (Blastocatellaceae, Rokubacteriales), but inhibited Cyanobacteria involved in nitrogen-fixing process. Network analysis showed that the bacterial community enhanced intraspecific cooperation, while fungal community mainly altered the keystone taxa under BaP stress. Biolog EcoPlate assay demonstrated that microbial metabolism of carbon sources, especially nitrogen-containing sources, was stimulated by BaP addition. Functional analysis based on enzyme activity tests, functional gene quantification, and function annotation showed that nitrogen-cycling processes, especially nitrogen fixation, were significantly inhibited. These results suggest that BaP-tolerant microbes may establish cooperative relationships and compete for resources and ecological niches with sensitive microbes, especially those associated with nitrogen cycling, ultimately leading to enhanced carbon source utilization and restricted nitrogen cycling. This study clearly elucidates the adaptation strategies and functional shifts of soil microbial communities to BaP contamination.
Collapse
Affiliation(s)
- Meiling Yi
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China; Key Laboratory of Three Gorges Reservoir Region's Eco-environment, Ministry of Education, Chongqing University, Chongqing 400045, China
| | - Lilan Zhang
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China; Key Laboratory of Three Gorges Reservoir Region's Eco-environment, Ministry of Education, Chongqing University, Chongqing 400045, China.
| | - Yang Li
- School of Environment, Beijing Normal University, Beijing 100875, China
| | - Yao Qian
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China; Key Laboratory of Three Gorges Reservoir Region's Eco-environment, Ministry of Education, Chongqing University, Chongqing 400045, China
| |
Collapse
|
23
|
Conservation and Evolution of the Sporulation Gene Set in Diverse Members of the Firmicutes. J Bacteriol 2022; 204:e0007922. [PMID: 35638784 DOI: 10.1128/jb.00079-22] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The current classification of the phylum Firmicutes (new name, Bacillota) features eight distinct classes, six of which include known spore-forming bacteria. In Bacillus subtilis, sporulation involves up to 500 genes, many of which do not have orthologs in other bacilli and/or clostridia. Previous studies identified about 60 sporulation genes of B. subtilis that were shared by all spore-forming members of the Firmicutes. These genes are referred to as the sporulation core or signature, although many of these are also found in genomes of nonsporeformers. Using an expanded set of 180 firmicute genomes from 160 genera, including 76 spore-forming species, we investigated the conservation of the sporulation genes, in particular seeking to identify lineages that lack some of the genes from the conserved sporulation core. The results of this analysis confirmed that many small acid-soluble spore proteins (SASPs), spore coat proteins, and germination proteins, which were previously characterized in bacilli, are missing in spore-forming members of Clostridia and other classes of Firmicutes. A particularly dramatic loss of sporulation genes was observed in the spore-forming members of the families Planococcaceae and Erysipelotrichaceae. Fifteen species from diverse lineages were found to carry skin (sigK-interrupting) elements of different sizes that all encoded SpoIVCA-like recombinases but did not share any other genes. Phylogenetic trees built from concatenated alignments of sporulation proteins and ribosomal proteins showed similar topology, indicating an early origin and subsequent vertical inheritance of the sporulation genes. IMPORTANCE Many members of the phylum Firmicutes (Bacillota) are capable of producing endospores, which enhance the survival of important Gram-positive pathogens that cause such diseases as anthrax, botulism, colitis, gas gangrene, and tetanus. We show that the core set of sporulation genes, defined previously through genome comparisons of several bacilli and clostridia, is conserved in a wide variety of sporeformers from several distinct lineages of Firmicutes. We also detected widespread loss of sporulation genes in many organisms, particularly within the families Planococcaceae and Erysipelotrichaceae. Members of these families, such as Lysinibacillus sphaericus and Clostridium innocuum, could be excellent model organisms for studying sporulation mechanisms, such as engulfment, formation of the spore coat, and spore germination.
Collapse
|
24
|
Xiao N, Wang B, Huang JJ, Huang Z, Shi L. Aeration strategy based on numerical modelling and the response mechanism of microbial communities under various operating conditions. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 310:114752. [PMID: 35231691 DOI: 10.1016/j.jenvman.2022.114752] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 02/10/2022] [Accepted: 02/15/2022] [Indexed: 06/14/2023]
Abstract
Aeration system is the main energy consumer in a wastewater treatment process. In this paper, the Naive Bayes classification (NBC) algorithm and response surface method (RSM) were firstly used to establish a methodology to improve the aeration efficiency and estimate effluent quality. Lab-scale experiments were conducted to verify the model. The errors between experimental values and predicted values were 3.36, -0.67 and -3.78% at operating temperatures of 20, 30 and 35 °C, indicating the applicability. To further elucidate the biological mechanisms of the experimental results, the microbial community composition was investigated under various operating conditions, the results shows that aerobic heterotrophic bacteria (HET) activity and COD removal efficiency were promoted at 30 °C. AOB and NOB activity and NH4+-N removal efficiency were promoted at 30-35 °C. These findings together suggest that operating temperature is crucial for activated sludge treatment, which should be considered when regulating DO content or aeration rate in practical application.
Collapse
Affiliation(s)
- Nan Xiao
- College of Environmental Science and Engineering/Sino-Canada Joint R&D Centre on Water and Environmental Safety, Nankai University, Tianjin, 300071, PR China
| | - Bing Wang
- College of Environmental Science and Engineering/Sino-Canada Joint R&D Centre on Water and Environmental Safety, Nankai University, Tianjin, 300071, PR China
| | - Jeanne Jinhui Huang
- College of Environmental Science and Engineering/Sino-Canada Joint R&D Centre on Water and Environmental Safety, Nankai University, Tianjin, 300071, PR China.
| | - Zhiyong Huang
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, PR China
| | - Liuyang Shi
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, PR China
| |
Collapse
|
25
|
Ren LF, Chen K, Zhang X, Xu Y, Chen L, Shao J, He Y. Effect of aniline and antimony on anaerobic-anoxic-oxic system with novel amidoxime-modified polyacrylonitrile adsorbent for wastewater treatment. BIORESOURCE TECHNOLOGY 2022; 351:127082. [PMID: 35358677 DOI: 10.1016/j.biortech.2022.127082] [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] [Received: 01/21/2022] [Revised: 03/24/2022] [Accepted: 03/25/2022] [Indexed: 06/14/2023]
Abstract
There has been increasing concern over the mixed discharge of municipal-textile composite wastewater, which remains challenging for typical wastewater treatment plant (WWTP) using anaerobic-anoxic-oxic process (AAO). Highly-toxic aniline and antimony, typical co-contaminants in textile wastewater, usually lead to increased chemical oxygen demand (COD) in influent and deteriorated effluent quality. Amidoxime-modified polyacrylonitrile (amPAN) adsorbent was prepared and added to adsorb antimony and facilitate substrate removal. With amPAN dosage at 6.0 g L-1 in oxic bioreactor, 64.2 ± 5.6% of antimony was removed from influent. Extracellular polymeric substance release was simultaneously changed with residual antimony concentration. Meanwhile, amPAN promoted the proliferation of Proteobacteria, Bacteroidetes and Epsilonbacteraeota serving as microorganism carrier. As a result, removal efficiencies of COD (94.4 ± 0.6%), ammonium (NH4+-N, 92.6 ± 3.3%), total nitrogen (TN, 76.4 ± 6.3%) and total phosphorus (TP, 93.4 ± 2.1%) were enhanced to meet Class 1A discharge standard in China. These results indicate that AAO with amPAN is promising for municipal-textile composite wastewater treatment.
Collapse
Affiliation(s)
- Long-Fei Ren
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, No. 800 Dongchuan Road, Shanghai 200240, PR China; Chongqing Research Institute, Shanghai Jiao Tong University, No. 598 Liangjiang Road, Chongqing 401135, PR China
| | - Kai Chen
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, No. 800 Dongchuan Road, Shanghai 200240, PR China
| | - Xiaofan Zhang
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, No. 800 Dongchuan Road, Shanghai 200240, PR China
| | - Yubo Xu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, No. 800 Dongchuan Road, Shanghai 200240, PR China
| | - Lei Chen
- National Engineering Research Center of Urban Water Resources, No. 230 Xuchang Road, Shanghai 200082, PR China
| | - Jiahui Shao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, No. 800 Dongchuan Road, Shanghai 200240, PR China.
| | - Yiliang He
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, No. 800 Dongchuan Road, Shanghai 200240, PR China
| |
Collapse
|
26
|
Abe K, Kato H, Hasegawa Y, Yamamoto T, Nomura N, Obana N. Visualization and characterization of spore morphogenesis in Paenibacillus polymyxa ATCC39564. J GEN APPL MICROBIOL 2022; 68:79-86. [PMID: 35418538 DOI: 10.2323/jgam.2021.10.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Paenibacillus polymyxa is a spore-forming Gram-positive bacterial species. Both its sporulation process and the spore properties are poorly understood. Here, we investigated sporulation in P. polymyxa ATCC39564. When cultured at 37℃ for 24 h in sporulation medium, more than 80% of the total cells in the culture were spores. Time-lapse imaging revealed that cellular morphological changes during sporulation of P. polymyxa were highly similar to those of B. subtilis. We demonstrated that genetic deletion of spo0A, sigE, sigF, sigG, or sigK, which are highly conserved transcriptional regulators in spore forming bacteria, abolished spore formation. In P. polymyxa, spo0A was required for cell growth in sporulation medium, as well as for the initiation of sporulation. The sigE and sigF mutants formed abnormal multiple asymmetric septa during the early stage of sporulation. The sigG and sigK mutants formed forespores in the sporangium, but they did not become mature. Moreover, fluorescence reporter analysis confirmed compartment-specific gene expression of spoIID and spoVFA in the mother cell and spoIIQ and sspF in the forespore. Transmission electron microscopy imaging revealed that P. polymyxa produces multilayered endospores but lacking a balloon-shaped exosporium. Our results indicate that spore morphogenesis is conserved between P. polymyxa and B. subtilis. However, P. polymyxa genomes lack many homologues encoding spore-coat proteins that are found in B. subtills, suggesting that there are differences in the spore coat composition and surface structure between P. polymyxa and B. subtilis.
Collapse
Affiliation(s)
- Kimihiro Abe
- Faculty of Life and Environmental Sciences, University of Tsukuba
| | - Hiroko Kato
- Gradudate School of Life and Environmental Sciences, University of Tsukuba
| | - Yuta Hasegawa
- Gradudate School of Life and Environmental Sciences, University of Tsukuba
| | - Tatsuya Yamamoto
- Faculty of Life and Environmental Sciences, University of Tsukuba
| | - Nobuhiko Nomura
- Faculty of Life and Environmental Sciences, University of Tsukuba.,Microbiology Research Center for Sustainability, University of Tsukuba
| | - Nozomu Obana
- Microbiology Research Center for Sustainability, University of Tsukuba.,Transborder Medical Research Center, Faculty of Medicine, University of Tsukuba
| |
Collapse
|
27
|
Paredes-Sabja D, Cid-Rojas F, Pizarro-Guajardo M. Assembly of the exosporium layer in Clostridioides difficile spores. Curr Opin Microbiol 2022; 67:102137. [PMID: 35182899 DOI: 10.1016/j.mib.2022.01.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 01/14/2022] [Accepted: 01/20/2022] [Indexed: 02/07/2023]
Abstract
Clostridioides difficile is a Gram-positive, spore-forming obligate anaerobe and a major threat to the healthcare system world-wide. Because of its strict anaerobic requirements, the infectious and transmissible morphotype is the dormant spore. During infection, C. difficile produces spores that can persist in the host and are responsible for disease recurrence and transmission, especially between hospitalized patients. Although the C. difficile spore surface mediates critical interactions with host surfaces, this outermost layer, known as the exosporium, is poorly conserved when compared to members of the Bacillus genus. Notably, the exosporium has been shown to be important for the persistence of C. difficile in the host. In this review, the ultrastructural properties, composition, and morphogenesis of the exosporium will be discussed.
Collapse
Affiliation(s)
- Daniel Paredes-Sabja
- Department of Biology, Texas A&M University, College Station, TX, 77843, USA; ANID - Millennium Science Initiative Program - Millennium Nucleus in the Biology of the Intestinal Microbiota, Santiago, Chile.
| | - Francisca Cid-Rojas
- Department of Biology, Texas A&M University, College Station, TX, 77843, USA; ANID - Millennium Science Initiative Program - Millennium Nucleus in the Biology of the Intestinal Microbiota, Santiago, Chile
| | - Marjorie Pizarro-Guajardo
- Department of Biology, Texas A&M University, College Station, TX, 77843, USA; ANID - Millennium Science Initiative Program - Millennium Nucleus in the Biology of the Intestinal Microbiota, Santiago, Chile
| |
Collapse
|
28
|
Effect of hydrothermal treatment on organic matter degradation, phytotoxicity, and microbial communities in model food waste composting. J Biosci Bioeng 2022; 133:382-389. [PMID: 35115228 DOI: 10.1016/j.jbiosc.2022.01.004] [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: 06/06/2021] [Revised: 01/11/2022] [Accepted: 01/11/2022] [Indexed: 01/17/2023]
Abstract
Hydrothermal treatment (HTT) as a pretreatment method for compost raw material has multiple benefits such as enhanced solubility of organic material, improved bioaugmentation, and reduced biohazard by killing harmful microorganisms. In this study, we pretreated food waste via HTT at 180 °C for 30 min to investigate its effect on food waste composting. HTT generated 8.98 mg/g-dry solid (g-ds) of 5-hydroxymethylfurfural and 4.32 mg/g-ds furfural. These furan compounds were completely decomposed in the early stage of composting, subsequently the organic matter in the food waste started to be degraded. The HTT-pretreated experiment demonstrated less organic matter degradation during composting as well as lower compost phytotoxicity compared to the non-HTT-pretreated experiment, where the conversion of carbon was 25.2% and the germination index value was 55%. HTT probably denatured part of the organic matter and making it more difficult to decompose, thereby preventing the rapid release of high concentrations of phytotoxic compounds such as organic acids and ammonium ions during composting. High-throughput microbial community analysis revealed that only Firmicutes appeared in the HTT-pretreated experiment, however, other bacterial groups also appeared in the non-HTT-pretreated experiment. This was possibly influenced by furan compounds and the changes of easily degradable organic matter to hardly degradable. Bacillus and Lysinibacillus were dominant in both composting experiments during vigorous organic matter degradation, suggesting that these bacterial groups were the main contributors to food waste composting. This study suggests that HTT is advantageous for the pretreatment of easily degradable food waste, as compost with less phytotoxicity was produced.
Collapse
|
29
|
Yuan Z, Xu W, He Z, Shen H. Poplar Sawdust Stack Self-Heating Properties and Variations of Internal Microbial Communities. MATERIALS 2022; 15:ma15031114. [PMID: 35161059 PMCID: PMC8840308 DOI: 10.3390/ma15031114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 01/20/2022] [Accepted: 01/26/2022] [Indexed: 11/16/2022]
Abstract
The heat accumulation generated by microbial metabolic activities during the storage of the sawdust may lead to spontaneous combustion accidents. This paper studied the Critical Ambient Temperature (CAT) variation of poplar sawdust at different stack dimensions and investigated the physicochemical properties as well as microbial community dynamics during the self-heating process of poplar sawdust stacks. From the self-heating substances test experiments and Frank-Kamenetskii (FK) theory, it was found that the CAT of poplar sawdust stacks would decrease from 158.27 °C to 102.46 °C with the increase of stack size from 0.1 m to 3.2 m. From the sawdust stack self-heating experiments, microbial metabolic activities were enhanced with the increasing moisture content (by watering) and oxygen (by turning over), which led to a remarkable increase of the sawdust stack temperature and the rapid decomposition of biochemical components (especially cellulose and hemicellulose). From the microbiological community analysis, at the thermophilic stage (around 60 °C, large amounts of heat release in compost bin), the existence of thermostable bacteria (such as Brevibacillus thermoruber, Bacillus thermoamylovorans and Paenibacillus barengoltzii belonging to Firmicutes) played an important role in degrading organic substances. The heat generated by the microbial metabolic activities might lead to spontaneous combustion eventually if sawdust stack is large enough. Therefore, the sawdust should be stacked in a cool and dry area while avoiding large amounts of storage in high humidity environments.
Collapse
Affiliation(s)
- Zitao Yuan
- Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control & Guangzhou Key Laboratory Environmental Catalysis and Pollution Control, School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China; (W.X.); (Z.H.)
- Correspondence: (Z.Y.); (H.S.)
| | - Wenbin Xu
- Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control & Guangzhou Key Laboratory Environmental Catalysis and Pollution Control, School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China; (W.X.); (Z.H.)
| | - Zili He
- Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control & Guangzhou Key Laboratory Environmental Catalysis and Pollution Control, School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China; (W.X.); (Z.H.)
| | - Hao Shen
- Guangdong Provincial Key Laboratory of Fire Science and Technology, School of Intelligent Systems Engineering, Sun Yat-sen University, Guangzhou 510006, China
- Correspondence: (Z.Y.); (H.S.)
| |
Collapse
|
30
|
Luu J, Mott CM, Schreiber OR, Giovinco HM, Betchen M, Carabetta VJ. Nε-Lysine Acetylation of the Histone-Like Protein HBsu Regulates the Process of Sporulation and Affects the Resistance Properties of Bacillus subtilis Spores. Front Microbiol 2022; 12:782815. [PMID: 35111139 PMCID: PMC8801598 DOI: 10.3389/fmicb.2021.782815] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 12/16/2021] [Indexed: 12/13/2022] Open
Abstract
Bacillus subtilis produces dormant, highly resistant endospores in response to extreme environmental stresses or starvation. These spores are capable of persisting in harsh environments for many years, even decades, without essential nutrients. Part of the reason that these spores can survive such extreme conditions is because their chromosomal DNA is well protected from environmental insults. The α/β-type small acid-soluble proteins (SASPs) coat the spore chromosome, which leads to condensation and protection from such insults. The histone-like protein HBsu has been implicated in the packaging of the spore chromosome and is believed to be important in modulating SASP-mediated alterations to the DNA, including supercoiling and stiffness. Previously, we demonstrated that HBsu is acetylated at seven lysine residues, and one physiological function of acetylation is to regulate chromosomal compaction. Here, we investigate if the process of sporulation or the resistance properties of mature spores are influenced by the acetylation state of HBsu. Using our collection of point mutations that mimic the acetylated and unacetylated forms of HBsu, we first determined if acetylation affects the process of sporulation, by determining the overall sporulation frequencies. We found that specific mutations led to decreases in sporulation frequency, suggesting that acetylation of HBsu at some sites, but not all, is required to regulate the process of sporulation. Next, we determined if the spores produced from the mutant strains were more susceptible to heat, ultraviolet (UV) radiation and formaldehyde exposure. We again found that altering acetylation at specific sites led to less resistance to these stresses, suggesting that proper HBsu acetylation is important for chromosomal packaging and protection in the mature spore. Interestingly, the specific acetylation patterns were different for the sporulation process and resistance properties of spores, which is consistent with the notion that a histone-like code exists in bacteria. We propose that specific acetylation patterns of HBsu are required to ensure proper chromosomal arrangement, packaging, and protection during the process of sporulation.
Collapse
Affiliation(s)
- Jackson Luu
- Department of Biomedical Sciences, Cooper Medical School of Rowan University, Camden, NJ, United States
| | - Connor M. Mott
- Department of Biomedical Sciences, Cooper Medical School of Rowan University, Camden, NJ, United States
| | - Olivia R. Schreiber
- Department of Biomedical Sciences, Cooper Medical School of Rowan University, Camden, NJ, United States
| | - Holly M. Giovinco
- Department of Biomedical Sciences, Cooper Medical School of Rowan University, Camden, NJ, United States
| | - Melanie Betchen
- Department of Internal Medicine, Cooper University Hospital, Camden, NJ, United States
| | - Valerie J. Carabetta
- Department of Biomedical Sciences, Cooper Medical School of Rowan University, Camden, NJ, United States
- *Correspondence: Valerie J. Carabetta,
| |
Collapse
|
31
|
Moreira ZPM, Helgason BL, Germida JJ. Assembly and potential transmission of the lens culinaris seed microbiome. FEMS Microbiol Ecol 2021; 97:6484792. [PMID: 34958355 DOI: 10.1093/femsec/fiab166] [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: 08/30/2021] [Accepted: 12/22/2021] [Indexed: 11/12/2022] Open
Abstract
Soil is an important source of bacteria and fungi for the plant, but seeds can also provide microbial inocula through heritable or stochastic assembly. Seed-associated microbial communities can potentially interact with the host plant through multiple generations. Here, we assessed the impact of two different soil types on the seed microbiome assembly of seven lentil (Lens culinaris) genotypes under environmentally controlled conditions and examined the vertical transmission of bacterial communities from seed to seed across two generations. Bulk soil microbiomes and seed microbiomes were characterized using high-throughput amplicon sequencing of the bacterial 16S rRNA gene. Our results revealed that bacterial communities in the two soils differed significantly and that bacterial communities associated with seeds were significantly impacted by genotype (15%) in one of the soils. Co-occurrence of amplicon sequence variants (ASVs) between generations suggests members of the genera Cutibacterium, Methylobacterium, Sphingomonas, Streptococcus, and Tepidimonas are transmitted and preserved in lentil genotypes irrespective of the soil in which they were grown. Increasing our knowledge of how microbial communities carried by seeds are assembled, transmitted, and preserved offers a promising way for future breeding programs to consider microbial communities when selecting for more resilient and productive cultivars.
Collapse
Affiliation(s)
- Zayda P Morales Moreira
- Department of Food and Bioproduct Sciences, University of Saskatchewan, Saskatoon, SK, Canada.,Department of Microbiology and Immunology, The University of British Columbia, Vancouver, BC, Canada
| | - Bobbi L Helgason
- Department of Soil Science, University of Saskatchewan, Saskatoon, SK, Canada
| | - James J Germida
- Department of Soil Science, University of Saskatchewan, Saskatoon, SK, Canada
| |
Collapse
|
32
|
Cai Z, Li H, Pu S, Ke J, Wang D, Liu Y, Chen J, Guo R. Development of autotrophic and heterotrophic consortia via immobilized microbial beads for chemical wastewater treatment, using PTA wastewater as an approach. CHEMOSPHERE 2021; 281:131001. [PMID: 34289638 DOI: 10.1016/j.chemosphere.2021.131001] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 05/12/2021] [Accepted: 05/23/2021] [Indexed: 06/13/2023]
Abstract
Studies on the symbiosis of microalgae-bacteria have been accelerating as a mean for wastewater remediation. However, there were few reports about the microalgae-bacteria consortia for chemical wastewater treatment. The aim of the present study is to develop an autotrophic and heterotrophic consortium for chemical wastewater treatment and probe whether and how bacteria could benefit from the microalgae during the treatment process, using PTA wastewater as an approach. A process-dependent strategy was applied. First of all, the results showed that the sludge beads with the sludge concentration of 30 g/L were the optimal one with the COD removal rate at 84.8% but the ceiling effect occurred (COD removal rate < 90%) even several common reinforcement methods were applied. Additionally, by adding the microalgae Chlorella vulgaris, a microalgae-activated sludge consortium was formed inside the immobilized beads, which provided better performance to shatter the ceiling effect. The COD remove rate was higher than 90%, regardless of the activated sludge was pre-culture or not. COD removal capacity could also be improved (COD removal rate > 92%) when LEDs light belt was offered as an advanced light condition. Biochemical assay and DNA analysis indicated that the microalgae could form an internal circulation of substances within the activated sludge and drove the microbial community to success and the corresponding gene functions, like metabolism and.
Collapse
Affiliation(s)
- Zhibin Cai
- China Pharmaceutical University, Nanjing, 211198, China
| | - Haitao Li
- Research Institute of Nanjing Chemical Industry Group, Nanjing, 210048, China
| | - Shaochen Pu
- China Pharmaceutical University, Nanjing, 211198, China
| | - Jian Ke
- China Pharmaceutical University, Nanjing, 211198, China
| | - Dong Wang
- Research Institute of Nanjing Chemical Industry Group, Nanjing, 210048, China
| | - Yanhua Liu
- China Pharmaceutical University, Nanjing, 211198, China
| | - Jianqiu Chen
- China Pharmaceutical University, Nanjing, 211198, China.
| | - Ruixin Guo
- China Pharmaceutical University, Nanjing, 211198, China.
| |
Collapse
|
33
|
Zhang M, Wang ZJ, Huang JC, Sun S, Cui X, Zhou W, He S. Salinity-driven nitrogen removal and its quantitative molecular mechanisms in artificial tidal wetlands. WATER RESEARCH 2021; 202:117446. [PMID: 34314924 DOI: 10.1016/j.watres.2021.117446] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Revised: 06/30/2021] [Accepted: 07/14/2021] [Indexed: 06/13/2023]
Abstract
The present study investigated the performance in nitrogen removal and associated nitrogen transformation processes in seven mesocosms fed with saline water (0‰ to 30‰) to simulate tidal flow constructed wetlands (TF CWs). The highly effective and steady removal of NH4+-N (84.74% averagely) was obtained at various salinities, while the rates varied from 6.34% to 89.19% and 22.54% to 87.48% for NO3--N and total nitrogen (TN), respectively. Overall, nitrogen removal efficiencies were greater at lower salinities. Molecular biological analyses verified the co-occurrence of dissimilatory nitrate reduction to ammonium (DNRA), denitrification, anaerobic ammonium oxidation (anammox) and nitrification in the mesocosms, reportedly contributing to nitrogen removal in TF CWs. The absolute copy numbers of nitrogen functional genes and total bacterial 16S rRNA were 2.54 × 103-7.35 × 107 and 3.21 × 107-7.82 × 109 copies g-1 dg (dry gravel), respectively, with the dominant phyla, i.e., Chloroflexi, Proteobacteria, Actinobacteriota, Cyanobacteria, and Firmicutes, accounting for over 80% of the sequences. The relative abundances of the genera related to nitrification and dissimilatory nitrate reduction processes, i.e., denitrification, anammox and DNRA, varied from 0.16% to 0.89% and from 3.66% to 11.59%, respectively, while quantitative relationships confirmed NH4+-N transformation rate was jointly controlled by amoA, hzsB, nxrA and nrfA, and NO3--N removal rate by nirS, nosZ, narG, qnorB and nxrA. These findings may shed light on quantitative molecular mechanisms for nitrogen removal in TF CWs for the saline water treatment, providing a sustainable solution to nitrogen pollution problem in the estuary ecosystem.
Collapse
Affiliation(s)
- Manping Zhang
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, PR China
| | - Zi-Jing Wang
- Department of Environmental Engineering, National Cheng Kung University, Tainan City 701, Taiwan
| | - Jung-Chen Huang
- Department of Environmental Engineering, National Cheng Kung University, Tainan City 701, Taiwan.
| | - Shanshan Sun
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, PR China
| | - Xijun Cui
- China-UK Low Carbon College, Shanghai Jiao Tong University, Shanghai 201306, PR China
| | - Weili Zhou
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, PR China
| | - Shengbing He
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, PR China
| |
Collapse
|
34
|
Zhu D, Patabendige HMLW, Tomlinson BR, Wang S, Hussain S, Flores D, He Y, Shaw LN, Sun X. Cwl0971, a novel peptidoglycan hydrolase, plays pleiotropic roles in Clostridioides difficile R20291. Environ Microbiol 2021; 23:5222-5238. [PMID: 33893759 PMCID: PMC11217927 DOI: 10.1111/1462-2920.15529] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 04/12/2021] [Indexed: 02/04/2023]
Abstract
Clostridioides difficile is a Gram-positive, spore-forming, toxin-producing anaerobe that can cause nosocomial antibiotic-associated intestinal disease. Although the production of toxin A (TcdA) and toxin B (TcdB) contribute to the main pathogenesis of C. difficile, the mechanism of TcdA and TcdB release from cell remains unclear. In this study, we identified and characterized a new cell wall hydrolase Cwl0971 (CDR20291_0971) from C. difficile R20291, which is involved in bacterial autolysis. The gene 0971 deletion mutant (R20291Δ0971) generated with CRISPR-AsCpfI exhibited significantly delayed cell autolysis and increased cell viability compared to R20291, and the purified Cwl0971 exhibited hydrolase activity for Bacillus subtilis cell wall. Meanwhile, 0971 gene deletion impaired TcdA and TcdB release due to the decreased cell autolysis in the stationary/late phase of cell growth. Moreover, sporulation of the mutant strain decreased significantly compared to the wild type strain. In vivo, the defect of Cwl0971 decreased fitness over the parent strain in a mouse infection model. Collectively, Cwl0971 is involved in cell wall lysis and cell viability, which affects toxin release, sporulation, germination, and pathogenicity of R20291, indicating that Cwl0971 could be an attractive target for C. difficile infection therapeutics and prophylactics.
Collapse
Affiliation(s)
- Duolong Zhu
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida
| | | | - Brooke Rene Tomlinson
- Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, Florida
| | - Shaohui Wang
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida
| | - Syed Hussain
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida
| | - Domenica Flores
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida
| | - Yongqun He
- Department of Microbiology and Immunology, and Center for Computational Medicine and Bioinformatics, Unit for Laboratory Animal Medicine, University of Michigan Medical School, Ann Arbor, Michigan
| | - Lindsey N. Shaw
- Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, Florida
| | - Xingmin Sun
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida
| |
Collapse
|
35
|
Shen A. Clostridioides difficile Spore Formation and Germination: New Insights and Opportunities for Intervention. Annu Rev Microbiol 2021; 74:545-566. [PMID: 32905755 DOI: 10.1146/annurev-micro-011320-011321] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Spore formation and germination are essential for the bacterial pathogen Clostridioides difficile to transmit infection. Despite the importance of these developmental processes to the infection cycle of C. difficile, the molecular mechanisms underlying how this obligate anaerobe forms infectious spores and how these spores germinate to initiate infection were largely unknown until recently. Work in the last decade has revealed that C. difficile uses a distinct mechanism for sensing and transducing germinant signals relative to previously characterized spore formers. The C. difficile spore assembly pathway also exhibits notable differences relative to Bacillus spp., where spore formation has been more extensively studied. For both these processes, factors that are conserved only in C. difficile or the related Peptostreptococcaceae family are employed, and even highly conserved spore proteins can have differential functions or requirements in C. difficile compared to other spore formers. This review summarizes our current understanding of the mechanisms controlling C. difficile spore formation and germination and describes strategies for inhibiting these processes to prevent C. difficile infection and disease recurrence.
Collapse
Affiliation(s)
- Aimee Shen
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts 02111, USA;
| |
Collapse
|
36
|
Shi L, Zhang P, He Y, Zeng F, Xu J, He L. Enantioselective effects of cyflumetofen on microbial community and related nitrogen cycle gene function in acid-soil. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 771:144831. [PMID: 33548698 DOI: 10.1016/j.scitotenv.2020.144831] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Revised: 11/26/2020] [Accepted: 12/19/2020] [Indexed: 06/12/2023]
Abstract
Cyflumetofen (CYF) is a novel chiral acaricide widely used in commercial crops to control mites. The environmental risks exposed by CYF in the soil, especially at the enantiomer level, remain unclear. We found that the (+)-CYF enantiomer was preferentially degraded in acid-soil, resulting in (-)-CYF enrichment. 16S rRNA and qPCR analysis indicated that decreased bacterial abundance by 12.79-61.80% and 2.52-52.48% in (-)-CYF treatment and (+)-CYF treatment, respectively. Diversity was also decreased with (-)-CYF treatment. Interestingly, several beneficial bacteria, for instance, Alphaproteobacteria (class), Sphingomonadaceae (family), and Arthrobacter (specise) were more enriched following (-)-CYF. The abundance of N2-fixing bacteria showed a sustained reduction with time, and the decrease was 3.24-72.94% with (-)-CYF and 25.37-73.11% with (+)-CYF treatment. Compared with the (+)-CYF treatment could positively promote nitrification, while the treatment (-)-CYF significantly reduced the abundance of amoA gene; namely it significantly negatively affected the nitrification in the nitrogen cycle. Through our further research, we found that Actinobacteria, Alphaproteobacteria, Lysobacter; Sphingomonas, Patescibacteria, Saccharimonadia, and Saccharimonadales showed synergistic effects with the nitrogen cycling-related genes nifH and amoA. These results contribute to a comprehensive environmental risk assessment of CYF in acid-soil at the enantiomer level.
Collapse
Affiliation(s)
- Linlin Shi
- Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing, China; State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China; Academy of Agricultural Sciences, Southwest University, Chongqing, China; State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Southwest University, Chongqing, China
| | - Ping Zhang
- Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing, China; Academy of Agricultural Sciences, Southwest University, Chongqing, China; State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Southwest University, Chongqing, China
| | - Yuhan He
- Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing, China; Academy of Agricultural Sciences, Southwest University, Chongqing, China; State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Southwest University, Chongqing, China
| | - Fanzhan Zeng
- Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing, China; Academy of Agricultural Sciences, Southwest University, Chongqing, China; State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Southwest University, Chongqing, China
| | - Jun Xu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.
| | - Lin He
- Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing, China; Academy of Agricultural Sciences, Southwest University, Chongqing, China; State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Southwest University, Chongqing, China.
| |
Collapse
|
37
|
Abstract
Clostridioides difficile is a leading cause of health care-associated infections worldwide. These infections are transmitted by C. difficile′s metabolically dormant, aerotolerant spore form. Functional spore formation depends on the assembly of two protective layers, a thick layer of modified peptidoglycan known as the cortex layer and a multilayered proteinaceous meshwork known as the coat. We previously identified two spore morphogenetic proteins, SpoIVA and SipL, that are essential for recruiting coat proteins to the developing forespore and making functional spores. While SpoIVA and SipL directly interact, the identities of the proteins they recruit to the forespore remained unknown. Here, we used mass spectrometry-based affinity proteomics to identify proteins that interact with the SpoIVA-SipL complex. These analyses identified the Peptostreptococcaceae family-specific, sporulation-induced bitopic membrane protein CD3457 (renamed SpoVQ) as a protein that interacts with SipL and SpoIVA. Loss of SpoVQ decreased heat-resistant spore formation by ∼5-fold and reduced cortex thickness ∼2-fold; the thinner cortex layer of ΔspoVQ spores correlated with higher levels of spontaneous germination (i.e., in the absence of germinant). Notably, loss of SpoVQ in either spoIVA or sipL mutants prevented cortex synthesis altogether and greatly impaired the localization of a SipL-mCherry fusion protein around the forespore. Thus, SpoVQ is a novel regulator of C. difficile cortex synthesis that appears to link cortex and coat formation. The identification of SpoVQ as a spore morphogenetic protein further highlights how Peptostreptococcaceae family-specific mechanisms control spore formation in C. difficile. IMPORTANCE The Centers for Disease Control has designated Clostridioides difficile as an urgent threat because of its intrinsic antibiotic resistance. C. difficile persists in the presence of antibiotics in part because it makes metabolically dormant spores. While recent work has shown that preventing the formation of infectious spores can reduce C. difficile disease recurrence, more selective antisporulation therapies are needed. The identification of spore morphogenetic factors specific to C. difficile would facilitate the development of such therapies. In this study, we identified SpoVQ (CD3457) as a spore morphogenetic protein specific to the Peptostreptococcaceae family that regulates the formation of C. difficile’s protective spore cortex layer. SpoVQ acts in concert with the known spore coat morphogenetic factors, SpoIVA and SipL, to link formation of the protective coat and cortex layers. These data reveal a novel pathway that could be targeted to prevent the formation of infectious C. difficile spores.
Collapse
|
38
|
Diallo M, Kengen SWM, López-Contreras AM. Sporulation in solventogenic and acetogenic clostridia. Appl Microbiol Biotechnol 2021; 105:3533-3557. [PMID: 33900426 PMCID: PMC8102284 DOI: 10.1007/s00253-021-11289-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 04/03/2021] [Accepted: 04/07/2021] [Indexed: 02/07/2023]
Abstract
The Clostridium genus harbors compelling organisms for biotechnological production processes; while acetogenic clostridia can fix C1-compounds to produce acetate and ethanol, solventogenic clostridia can utilize a wide range of carbon sources to produce commercially valuable carboxylic acids, alcohols, and ketones by fermentation. Despite their potential, the conversion by these bacteria of carbohydrates or C1 compounds to alcohols is not cost-effective enough to result in economically viable processes. Engineering solventogenic clostridia by impairing sporulation is one of the investigated approaches to improve solvent productivity. Sporulation is a cell differentiation process triggered in bacteria in response to exposure to environmental stressors. The generated spores are metabolically inactive but resistant to harsh conditions (UV, chemicals, heat, oxygen). In Firmicutes, sporulation has been mainly studied in bacilli and pathogenic clostridia, and our knowledge of sporulation in solvent-producing or acetogenic clostridia is limited. Still, sporulation is an integral part of the cellular physiology of clostridia; thus, understanding the regulation of sporulation and its connection to solvent production may give clues to improve the performance of solventogenic clostridia. This review aims to provide an overview of the triggers, characteristics, and regulatory mechanism of sporulation in solventogenic clostridia. Those are further compared to the current knowledge on sporulation in the industrially relevant acetogenic clostridia. Finally, the potential applications of spores for process improvement are discussed.Key Points• The regulatory network governing sporulation initiation varies in solventogenic clostridia.• Media composition and cell density are the main triggers of sporulation.• Spores can be used to improve the fermentation process.
Collapse
Affiliation(s)
- Mamou Diallo
- Wageningen Food and Biobased Research, Wageningen, The Netherlands.
- Laboratory of Microbiology, Wageningen University & Research, Wageningen, The Netherlands.
| | - Servé W M Kengen
- Laboratory of Microbiology, Wageningen University & Research, Wageningen, The Netherlands
| | | |
Collapse
|
39
|
Ma M, Welch RD, Garza AG. The σ 54 system directly regulates bacterial natural product genes. Sci Rep 2021; 11:4771. [PMID: 33637792 PMCID: PMC7910581 DOI: 10.1038/s41598-021-84057-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 02/05/2021] [Indexed: 01/31/2023] Open
Abstract
Bacterial-derived polyketide and non-ribosomal peptide natural products are crucial sources of therapeutics and yet little is known about the conditions that favor activation of natural product genes or the regulatory machinery controlling their transcription. Recent findings suggest that the σ54 system, which includes σ54-loaded RNA polymerase and transcriptional activators called enhancer binding proteins (EBPs), might be a common regulator of natural product genes. Here, we explored this idea by analyzing a selected group of putative σ54 promoters identified in Myxococcus xanthus natural product gene clusters. We show that mutations in putative σ54-RNA polymerase binding regions and in putative Nla28 EBP binding sites dramatically reduce in vivo promoter activities in growing and developing cells. We also show in vivo promoter activities are reduced in a nla28 mutant, that Nla28 binds to wild-type fragments of these promoters in vitro, and that in vitro binding is lost when the Nla28 binding sites are mutated. Together, our results indicate that M. xanthus uses σ54 promoters for transcription of at least some of its natural product genes. Interestingly, the vast majority of experimentally confirmed and putative σ54 promoters in M. xanthus natural product loci are located within genes and not in intergenic sequences.
Collapse
Affiliation(s)
- Muqing Ma
- grid.264484.80000 0001 2189 1568Department of Biology, Syracuse University, 107 College Place, Syracuse, NY 13244 USA
| | - Roy D. Welch
- grid.264484.80000 0001 2189 1568Department of Biology, Syracuse University, 107 College Place, Syracuse, NY 13244 USA
| | - Anthony G. Garza
- grid.264484.80000 0001 2189 1568Department of Biology, Syracuse University, 107 College Place, Syracuse, NY 13244 USA
| |
Collapse
|
40
|
Sun G, Yang M, Jiang L, Huang M. Regulation of pro-σ K activation: a key checkpoint in Bacillus subtilis sporulation. Environ Microbiol 2021; 23:2366-2373. [PMID: 33538382 DOI: 10.1111/1462-2920.15415] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 01/27/2021] [Accepted: 01/28/2021] [Indexed: 11/30/2022]
Abstract
The Gram-positive bacterium Bacillus subtilis initiates the sporulation process under conditions of nutrient limitation. Here, we review related work in this field, focusing on the protein processing of the pro-σK activation. The purpose of this review is to illustrate the mechanism of pro-σK activation and provide structural insights into the regulation of spore production. Sporulation is not only important in basic science but also provides mechanistic insight for bacterial control in applications in, e.g., food industry.
Collapse
Affiliation(s)
- Gaohui Sun
- College of Chemistry, Fuzhou University, Fuzhou, Fujian, 350016, China
| | - Moua Yang
- Division of Hemostasis and Thrombosis, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA
| | - Longguang Jiang
- College of Chemistry, Fuzhou University, Fuzhou, Fujian, 350016, China.,Fujian Key Laboratory of Marine Enzyme Engineering, Fuzhou University, Fuzhou, Fujian, 350116, China
| | - Mingdong Huang
- College of Chemistry, Fuzhou University, Fuzhou, Fujian, 350016, China
| |
Collapse
|
41
|
Geissler AS, Anthon C, Alkan F, González-Tortuero E, Poulsen LD, Kallehauge TB, Breüner A, Seemann SE, Vinther J, Gorodkin J. BSGatlas: a unified Bacillus subtilis genome and transcriptome annotation atlas with enhanced information access. Microb Genom 2021; 7:000524. [PMID: 33539279 PMCID: PMC8208703 DOI: 10.1099/mgen.0.000524] [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: 07/29/2020] [Accepted: 01/11/2021] [Indexed: 12/26/2022] Open
Abstract
A large part of our current understanding of gene regulation in Gram-positive bacteria is based on Bacillus subtilis, as it is one of the most well studied bacterial model systems. The rapid growth in data concerning its molecular and genomic biology is distributed across multiple annotation resources. Consequently, the interpretation of data from further B. subtilis experiments becomes increasingly challenging in both low- and large-scale analyses. Additionally, B. subtilis annotation of structured RNA and non-coding RNA (ncRNA), as well as the operon structure, is still lagging behind the annotation of the coding sequences. To address these challenges, we created the B. subtilis genome atlas, BSGatlas, which integrates and unifies multiple existing annotation resources. Compared to any of the individual resources, the BSGatlas contains twice as many ncRNAs, while improving the positional annotation for 70 % of the ncRNAs. Furthermore, we combined known transcription start and termination sites with lists of known co-transcribed gene sets to create a comprehensive transcript map. The combination with transcription start/termination site annotations resulted in 717 new sets of co-transcribed genes and 5335 untranslated regions (UTRs). In comparison to existing resources, the number of 5' and 3' UTRs increased nearly fivefold, and the number of internal UTRs doubled. The transcript map is organized in 2266 operons, which provides transcriptional annotation for 92 % of all genes in the genome compared to the at most 82 % by previous resources. We predicted an off-target-aware genome-wide library of CRISPR-Cas9 guide RNAs, which we also linked to polycistronic operons. We provide the BSGatlas in multiple forms: as a website (https://rth.dk/resources/bsgatlas/), an annotation hub for display in the UCSC genome browser, supplementary tables and standardized GFF3 format, which can be used in large scale -omics studies. By complementing existing resources, the BSGatlas supports analyses of the B. subtilis genome and its molecular biology with respect to not only non-coding genes but also genome-wide transcriptional relationships of all genes.
Collapse
Affiliation(s)
- Adrian Sven Geissler
- Center for Non-coding RNA in Technology and Health, Department of Veterinary and Animal Sciences, University of Copenhagen, 1871 Frederiksberg, Denmark
| | - Christian Anthon
- Center for Non-coding RNA in Technology and Health, Department of Veterinary and Animal Sciences, University of Copenhagen, 1871 Frederiksberg, Denmark
| | - Ferhat Alkan
- Center for Non-coding RNA in Technology and Health, Department of Veterinary and Animal Sciences, University of Copenhagen, 1871 Frederiksberg, Denmark
- Division of Oncogenomics, Netherlands Cancer Institute, 1066 CX Amsterdam, The Netherlands
| | - Enrique González-Tortuero
- Center for Non-coding RNA in Technology and Health, Department of Veterinary and Animal Sciences, University of Copenhagen, 1871 Frederiksberg, Denmark
- Present address: School of Science, Engineering and Environment, University of Salford, Salford, UK
| | - Line Dahl Poulsen
- Section for Computational and RNA Biology, Department of Biology, University of Copenhagen, 1165 Copenhagen, Denmark
| | | | | | - Stefan Ernst Seemann
- Center for Non-coding RNA in Technology and Health, Department of Veterinary and Animal Sciences, University of Copenhagen, 1871 Frederiksberg, Denmark
| | - Jeppe Vinther
- Section for Computational and RNA Biology, Department of Biology, University of Copenhagen, 1165 Copenhagen, Denmark
| | - Jan Gorodkin
- Center for Non-coding RNA in Technology and Health, Department of Veterinary and Animal Sciences, University of Copenhagen, 1871 Frederiksberg, Denmark
| |
Collapse
|
42
|
Combined and Distinct Roles of Agr Proteins in Clostridioides difficile 630 Sporulation, Motility, and Toxin Production. mBio 2020; 11:mBio.03190-20. [PMID: 33443122 PMCID: PMC8534292 DOI: 10.1128/mbio.03190-20] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The Clostridioides difficile accessory gene regulator 1 (agr1) locus consists of two genes, agrB1 and agrD1, that presumably constitute an autoinducing peptide (AIP) system. Typically, AIP systems function through the AgrB-mediated processing of AgrD to generate a processed form of the AIP that provides a concentration-dependent extracellular signal. Here, we show that the C. difficile 630 Agr1 system has multiple functions, not all of which depend on AgrB1. CRISPR-Cas9n deletion of agrB1, agrD1, or the entire locus resulted in changes in transcription of sporulation-related factors and an overall loss in spore formation. Sporulation was recovered in the mutants by providing supernatant from stationary-phase cultures of the parental strain. In contrast, C. difficile motility was reduced only when both AgrB1 and AgrD1 were disrupted. Finally, in the absence of AgrB1, the AgrD1 peptide accumulated within the cytoplasm and this correlated with increased expression of tcdR (15-fold), as well as tcdA (20-fold) and tcdB (5-fold), which encode the two major C. difficile toxins. The combined deletion of agrB1/agrD1 or deletion of only agrD1 did not significantly alter expression of tcdR or tcdB but did show a minor effect on tcdA expression. Overall, these data indicate that the Agr1-based system in C. difficile 630 carries out multiple functions, some of which are associated with prototypical AIP signaling and others of which involve previously undescribed mechanisms of action.IMPORTANCE C. difficile is a spore-forming, toxigenic, anaerobic bacterium that causes severe gastrointestinal illness. Understanding the ways in which C. difficile senses growth conditions to regulate toxin expression and sporulation is essential to advancing our understanding of this pathogen. The Agr1 system in C. difficile has been thought to function by generating an extracellular autoinducing peptide that accumulates and exogenously activates two-component signaling. The absence of the peptide or protease should, in theory, result in similar phenotypes. However, in contrast to longstanding assumptions about Agr, we found that mutants of individual agr1 genes exhibit distinct phenotypes in C. difficile These findings suggest that the Agr1 system may have other regulatory mechanisms independent of the typical Agr quorum sensing system. These data not only challenge models for Agr's mechanism of action in C. difficile but also may expand our conceptions of how this system works in other Gram-positive pathogens.
Collapse
|
43
|
Riley EP, Schwarz C, Derman AI, Lopez-Garrido J. Milestones in Bacillus subtilis sporulation research. MICROBIAL CELL (GRAZ, AUSTRIA) 2020; 8:1-16. [PMID: 33490228 PMCID: PMC7780723 DOI: 10.15698/mic2021.01.739] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 10/21/2020] [Accepted: 11/03/2020] [Indexed: 12/13/2022]
Abstract
Endospore formation has been a rich field of research for more than a century, and has benefited from the powerful genetic tools available in Bacillus subtilis. In this review, we highlight foundational discoveries that shaped the sporulation field, from its origins to the present day, tracing a chronology that spans more than one hundred eighty years. We detail how cell-specific gene expression has been harnessed to investigate the existence and function of intercellular proteinaceous channels in sporulating cells, and we illustrate the rapid progress in our understanding of the cell biology of sporulation in recent years using the process of chromosome translocation as a storyline. Finally, we sketch general aspects of sporulation that remain largely unexplored, and that we envision will be fruitful areas of future research.
Collapse
Affiliation(s)
- Eammon P. Riley
- Division of Biological Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Corinna Schwarz
- Max Planck Institute for Evolutionary Biology, Plön, Germany
| | - Alan I. Derman
- Max Planck Institute for Evolutionary Biology, Plön, Germany
| | | |
Collapse
|
44
|
Wettstadt S, Llamas MA. Role of Regulated Proteolysis in the Communication of Bacteria With the Environment. Front Mol Biosci 2020; 7:586497. [PMID: 33195433 PMCID: PMC7593790 DOI: 10.3389/fmolb.2020.586497] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 09/22/2020] [Indexed: 12/29/2022] Open
Abstract
For bacteria to flourish in different niches, they need to sense signals from the environment and translate these into appropriate responses. Most bacterial signal transduction systems involve proteins that trigger the required response through the modification of gene transcription. These proteins are often produced in an inactive state that prevents their interaction with the RNA polymerase and/or the DNA in the absence of the inducing signal. Among other mechanisms, regulated proteolysis is becoming increasingly recognized as a key process in the modulation of the activity of these signal response proteins. Regulated proteolysis can either produce complete degradation or specific cleavage of the target protein, thus modifying its function. Because proteolysis is a fast process, the modulation of signaling proteins activity by this process allows for an immediate response to a given signal, which facilitates adaptation to the surrounding environment and bacterial survival. Moreover, regulated proteolysis is a fundamental process for the transmission of extracellular signals to the cytosol through the bacterial membranes. By a proteolytic mechanism known as regulated intramembrane proteolysis (RIP) transmembrane proteins are cleaved within the plane of the membrane to liberate a cytosolic domain or protein able to modify gene transcription. This allows the transmission of a signal present on one side of a membrane to the other side where the response is elicited. In this work, we review the role of regulated proteolysis in the bacterial communication with the environment through the modulation of the main bacterial signal transduction systems, namely one- and two-component systems, and alternative σ factors.
Collapse
Affiliation(s)
- Sarah Wettstadt
- Department of Environmental Protection, Estación Experimental del Zaidín-Consejo Superior de Investigaciones Científicas, Granada, Spain
| | - María A Llamas
- Department of Environmental Protection, Estación Experimental del Zaidín-Consejo Superior de Investigaciones Científicas, Granada, Spain
| |
Collapse
|
45
|
Diallo M, Kint N, Monot M, Collas F, Martin-Verstraete I, van der Oost J, Kengen SWM, López-Contreras AM. Transcriptomic and Phenotypic Analysis of a spoIIE Mutant in Clostridium beijerinckii. Front Microbiol 2020; 11:556064. [PMID: 33042064 PMCID: PMC7522474 DOI: 10.3389/fmicb.2020.556064] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 08/20/2020] [Indexed: 11/26/2022] Open
Abstract
SpoIIE is a phosphatase involved in the activation of the first sigma factor of the forespore, σ F , during sporulation. A ΔspoIIE mutant of Clostridium beijerinckii NCIMB 8052, previously generated by CRISPR-Cas9, did not sporulate but still produced granulose and solvents. Microscopy analysis also showed that the cells of the ΔspoIIE mutant are elongated with the presence of multiple septa. This observation suggests that in C. beijerinckii, SpoIIE is necessary for the completion of the sporulation process, as seen in Bacillus and Clostridium acetobutylicum. Moreover, when grown in reactors, the spoIIE mutant produced higher levels of solvents than the wild type strain. The impact of the spoIIE inactivation on gene transcription was assessed by comparative transcriptome analysis at three time points (4 h, 11 h and 23 h). Approximately 5% of the genes were differentially expressed in the mutant compared to the wild type strain at all time points. Out of those only 12% were known sporulation genes. As expected, the genes belonging to the regulon of the sporulation specific transcription factors (σ F , σ E , σ G , σ K ) were strongly down-regulated in the mutant. Inactivation of spoIIE also caused differential expression of genes involved in various cell processes at each time point. Moreover, at 23 h, genes involved in butanol formation and tolerance, as well as in cell motility, were up-regulated in the mutant. In contrast, several genes involved in cell wall composition, oxidative stress and amino acid transport were down-regulated. These results indicate an intricate interdependence of sporulation and stationary phase cellular events in C. beijerinckii.
Collapse
Affiliation(s)
- Mamou Diallo
- Wageningen Food and Biobased Research, Wageningen, Netherlands
- Laboratory of Microbiology, Wageningen University, Wageningen, Netherlands
| | - Nicolas Kint
- Laboratoire Pathogènese des Bactéries Anaérobies, Institut Pasteur, UMR CNRS 2001, Université de Paris, Paris, France
| | - Marc Monot
- Biomics platform, C2RT, Institut Pasteur, Paris, France
| | - Florent Collas
- Wageningen Food and Biobased Research, Wageningen, Netherlands
| | - Isabelle Martin-Verstraete
- Laboratoire Pathogènese des Bactéries Anaérobies, Institut Pasteur, UMR CNRS 2001, Université de Paris, Paris, France
- Institut Universitaire de France, Paris, France
| | - John van der Oost
- Laboratory of Microbiology, Wageningen University, Wageningen, Netherlands
| | - Servé W. M. Kengen
- Laboratory of Microbiology, Wageningen University, Wageningen, Netherlands
| | | |
Collapse
|
46
|
Rousset L, Alpha-Bazin B, Château A, Armengaud J, Clavel T, Berge O, Duport C. Groundwater promotes emergence of asporogenic mutants of emetic Bacillus cereus. Environ Microbiol 2020; 22:5248-5264. [PMID: 32815215 DOI: 10.1111/1462-2920.15203] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 08/13/2020] [Accepted: 08/17/2020] [Indexed: 01/15/2023]
Abstract
Bacillus cereus is a ubiquitous endospore-forming bacterium, which mainly affects humans as a food-borne pathogen. Bacillus cereus can contaminate groundwater used to irrigate food crops. Here, we examined the ability of the emetic strain B. cereus F4810/72 to survive abiotic conditions encountered in groundwater. Our results showed that vegetative B. cereus cells rapidly evolved in a mixed population composed of endospores and asporogenic variants bearing spo0A mutations. One asporogenic variant, VAR-F48, was isolated and characterized. VAR-F48 can survive in sterilized groundwater over a long period in a vegetative form and has a competitive advantage compared to its parental strain. Proteomics analysis allowed us to quantify changes to cellular and exoproteins after 24 and 72 h incubation in groundwater, for VAR-F48 compared to its parental strain. The results revealed a significant re-routing of the metabolism in the absence of Spo0A. We concluded that VAR-F48 maximizes its energy use to deal with oligotrophy, and the emergence of spo0A-mutated variants may contribute to the persistence of emetic B. cereus in natural oligotrophic environments.
Collapse
Affiliation(s)
- Ludivine Rousset
- Avignon Université, INRAE, UMR SQPOV, Avignon, F-84914, France.,INRAE, Pathologie Végétale, Montfavet, F-84140, France
| | - Béatrice Alpha-Bazin
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SPI, Bagnols-sur-Cèze, 30200, France
| | - Alice Château
- Avignon Université, INRAE, UMR SQPOV, Avignon, F-84914, France
| | - Jean Armengaud
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SPI, Bagnols-sur-Cèze, 30200, France
| | - Thierry Clavel
- Avignon Université, INRAE, UMR SQPOV, Avignon, F-84914, France
| | - Odile Berge
- INRAE, Pathologie Végétale, Montfavet, F-84140, France
| | | |
Collapse
|
47
|
Xu L, Zhang B, Peng X, Zhang X, Sun B, Sun H, Jiang C, Zhou S, Zeng X, Bai Z, Xu S, Zhuang X. Dynamic variations of microbial community structure in Myriophyllum aquaticum constructed wetlands in response to different NH4+-N concentrations. Process Biochem 2020. [DOI: 10.1016/j.procbio.2020.02.028] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
|
48
|
Morovic W, Budinoff CR. Epigenetics: A New Frontier in Probiotic Research. Trends Microbiol 2020; 29:117-126. [PMID: 32409146 DOI: 10.1016/j.tim.2020.04.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 04/01/2020] [Accepted: 04/10/2020] [Indexed: 02/06/2023]
Abstract
Research into the benefits of probiotics has progressed beyond interventional studies to identifying the underlying molecular mechanisms. Health-promoting effector molecules produced by probiotics are well documented and have been linked to specific genes and even individual nucleotides. However, the factors controlling the expression of these molecules are poorly understood and we argue that epigenetic influences likely play an important role in mediating the health-promoting attributes of probiotics. Here, we review established epigenetic regulation of important microbial genetic systems involved in health promotion, safety, and industrialization to provide evidence that the same regulation occurs in probiotic organisms. We advocate for studies combining genomic and meta-epigenomic data to better understand the mode of action of probiotics, their associated microbiomes, and their effects on consumers.
Collapse
|
49
|
Fajardo C, Sánchez-Fortún S, Costa G, Nande M, Botías P, García-Cantalejo J, Mengs G, Martín M. Evaluation of nanoremediation strategy in a Pb, Zn and Cd contaminated soil. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 706:136041. [PMID: 31855644 DOI: 10.1016/j.scitotenv.2019.136041] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 12/06/2019] [Accepted: 12/08/2019] [Indexed: 05/04/2023]
Abstract
We addressed the efficiency of a nanoremediation strategy using zero-valent iron nanoparticles (nZVI), in a case of co-mingled heavy metals (HM) pollution (Pb, Cd and Zn). We applied a combined set of physical-chemical, toxicological and molecular analyses to assess the effectiveness and ecosafety of nZVI (5% w/w) for environmental restoration. After 120 days, nZVI showed immobilization capacity for Pb (20%), it was scarcely effective for Zn (8%) and negligibly effective for Cd. The HMs immobilization in the nZVI treated soils (compared to control soil), reaches its maximum after 15 days (T3) as reflected in the decrease of HM toxicity towards V. fischeri. The overall abundance of the microbial community was similar in both sets of samples during all experiment, although an increase in the number of metabolically active bacteria was recorded 15 days post treatment. We studied the induced impact of nanoremediation on the soil microbial community structure by Next Generation Sequencing (NGS). Even when higher HM immobilization was recorded, no significant recovery of the microbial community structure was found in nZVI-treated soil. The most marked nZVI-induced structural shifts were observed at T3 (increase in the Firmicutes population with a decrease in Gram-negative bacteria). Predictive metagenomic analysis using PICRUSt showed differences among the predicted metagenomes of nZVI-treated and control soils. At T3 we found decrease in detoxification-related proteins or over-representation of germination-related proteins; after 120 days of nZVI exposure, higher abundance of proteins involved in regulation of cellular processes or sporulation-related proteins was detected. This study highlights the partial effectiveness of nanoremediation in multiple-metal contaminated soil in the short term. The apparent lack of recovery of biodiversity after application of nZVI and the decreased effectiveness of nanoremediation over time must be carefully considered to validate this technology when assurance of medium- to long-term immobilization of HMs is required.
Collapse
Affiliation(s)
- Carmen Fajardo
- Facultad de Farmacia, Universidad de Alcalá, 28805 Alcalá de Henares (Madrid), Spain
| | | | - Gonzalo Costa
- Facultad de Veterinaria, Universidad Complutense, 28040 Madrid, Spain
| | - Mar Nande
- Facultad de Veterinaria, Universidad Complutense, 28040 Madrid, Spain
| | - Pedro Botías
- Unidad de Genómica, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | | | - Gerardo Mengs
- Facultad de Veterinaria, Universidad Complutense, 28040 Madrid, Spain
| | - Margarita Martín
- Facultad de Veterinaria, Universidad Complutense, 28040 Madrid, Spain
| |
Collapse
|
50
|
The Impact of Exogenous Aerobic Bacteria on Sustainable Methane Production Associated with Municipal Solid Waste Biodegradation: Revealed by High-Throughput Sequencing. SUSTAINABILITY 2020. [DOI: 10.3390/su12051815] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
In this work, the impact of exogenous aerobic bacteria mixture (EABM) on municipal solid waste (MSW) is well evaluated in the following aspects: biogas production, leachate analysis, organic waste degradation, EABM population, and the composition of microbial communities. The study was designed and performed as follows: the control bioreactor (R1) was filled up with MSW and the culture medium of EABM and the experimental bioreactor (R2) was filled up with MSW and EABM. The data suggests that the composition of microbial communities (bacterial and methanogenic) in R1 and R2 were similar at day 0, while the addition of EABM in R2 led to a differential abundance of Bacillus cereus, Bacillus subtilis, Staphylococcus saprophyticus, Staphlyoccus xylosus, and Pantoea agglomerans in two bioreactors. The population of exogenous aerobic bacteria in R2 greatly increased during hydrolysis and acidogenesis stages, and subsequently increased the degradation of volatile solid (VS), protein, lipid, and lignin by 59.25%, 25.68%, 60.47%, and 197.62%, respectively, compared to R1. The duration of hydrolysis and acidogenesis in R2 was 33.33% shorter than that in R1. At the end of the study, the accumulative methane yield in R2 (494.4 L) was almost three times more than that in R1 (187.4 L). In addition, the abundance of acetoclasic methanogens increased at acetogenesis and methanogenesis stages in both bioreactors, which indicates that acetoclasic methanogens (especially Methanoseata) could contribute to methane production. This study demonstrates that EABM can accelerate organic waste degradation to promote MSW biodegradation and methane production. Moreover, the operational parameters helped EABM to generate 20.85% more in accumulative methane yield. With a better understanding of how EABM affects MSW and the composition of bacterial community, this study offers a potential practical approach to MSW disposal and cleaner energy generation worldwide.
Collapse
|