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da Cruz Nizer WS, Adams ME, Allison KN, Montgomery MC, Mosher H, Cassol E, Overhage J. Oxidative stress responses in biofilms. Biofilm 2024; 7:100203. [PMID: 38827632 PMCID: PMC11139773 DOI: 10.1016/j.bioflm.2024.100203] [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: 02/28/2024] [Revised: 05/22/2024] [Accepted: 05/22/2024] [Indexed: 06/04/2024] Open
Abstract
Oxidizing agents are low-molecular-weight molecules that oxidize other substances by accepting electrons from them. They include reactive oxygen species (ROS), such as superoxide anions (O2-), hydrogen peroxide (H2O2), and hydroxyl radicals (HO-), and reactive chlorine species (RCS) including sodium hypochlorite (NaOCl) and its active ingredient hypochlorous acid (HOCl), and chloramines. Bacteria encounter oxidizing agents in many different environments and from diverse sources. Among them, they can be produced endogenously by aerobic respiration or exogenously by the use of disinfectants and cleaning agents, as well as by the mammalian immune system. Furthermore, human activities like industrial effluent pollution, agricultural runoff, and environmental activities like volcanic eruptions and photosynthesis are also sources of oxidants. Despite their antimicrobial effects, bacteria have developed many mechanisms to resist the damage caused by these toxic molecules. Previous research has demonstrated that growing as a biofilm particularly enhances bacterial survival against oxidizing agents. This review aims to summarize the current knowledge on the resistance mechanisms employed by bacterial biofilms against ROS and RCS, focussing on the most important mechanisms, including the formation of biofilms in response to oxidative stressors, the biofilm matrix as a protective barrier, the importance of detoxifying enzymes, and increased protection within multi-species biofilm communities. Understanding the complexity of bacterial responses against oxidative stress will provide valuable insights for potential therapeutic interventions and biofilm control strategies in diverse bacterial species.
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Affiliation(s)
| | - Madison Elisabeth Adams
- Department of Health Sciences, Carleton University, 1125 Colonel By Drive, Ottawa, K1S 5B6, ON, Canada
| | - Kira Noelle Allison
- Department of Health Sciences, Carleton University, 1125 Colonel By Drive, Ottawa, K1S 5B6, ON, Canada
| | | | - Hailey Mosher
- Department of Health Sciences, Carleton University, 1125 Colonel By Drive, Ottawa, K1S 5B6, ON, Canada
| | - Edana Cassol
- Department of Health Sciences, Carleton University, 1125 Colonel By Drive, Ottawa, K1S 5B6, ON, Canada
| | - Joerg Overhage
- Department of Health Sciences, Carleton University, 1125 Colonel By Drive, Ottawa, K1S 5B6, ON, Canada
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Gangwal A, Kumar N, Sangwan N, Dhasmana N, Dhawan U, Sajid A, Arora G, Singh Y. Giving a signal: how protein phosphorylation helps Bacillus navigate through different life stages. FEMS Microbiol Rev 2023; 47:fuad044. [PMID: 37533212 PMCID: PMC10465088 DOI: 10.1093/femsre/fuad044] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 07/30/2023] [Accepted: 08/01/2023] [Indexed: 08/04/2023] Open
Abstract
Protein phosphorylation is a universal mechanism regulating a wide range of cellular responses across all domains of life. The antagonistic activities of kinases and phosphatases can orchestrate the life cycle of an organism. The availability of bacterial genome sequences, particularly Bacillus species, followed by proteomics and functional studies have aided in the identification of putative protein kinases and protein phosphatases, and their downstream substrates. Several studies have established the role of phosphorylation in different physiological states of Bacillus species as they pass through various life stages such as sporulation, germination, and biofilm formation. The most common phosphorylation sites in Bacillus proteins are histidine, aspartate, tyrosine, serine, threonine, and arginine residues. Protein phosphorylation can alter protein activity, structural conformation, and protein-protein interactions, ultimately affecting the downstream pathways. In this review, we summarize the knowledge available in the field of Bacillus signaling, with a focus on the role of protein phosphorylation in its physiological processes.
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Affiliation(s)
- Aakriti Gangwal
- Department of Zoology, University of Delhi, Faculty of Science, Delhi- 110007, India
| | - Nishant Kumar
- Department of Zoology, University of Delhi, Faculty of Science, Delhi- 110007, India
| | - Nitika Sangwan
- Department of Zoology, University of Delhi, Faculty of Science, Delhi- 110007, India
- Department of Biomedical Science, Bhaskaracharya College of Applied Sciences, University of Delhi, New Delhi-110075, India
| | - Neha Dhasmana
- School of Medicine, New York University, 550 First Avenue New York-10016, New York, United States
| | - Uma Dhawan
- Department of Biomedical Science, Bhaskaracharya College of Applied Sciences, University of Delhi, New Delhi-110075, India
| | - Andaleeb Sajid
- 300 Cedar St, Yale School of Medicine, Yale University, New Haven, Connecticut 06520, New Haven CT, United States
| | - Gunjan Arora
- 300 Cedar St, Yale School of Medicine, Yale University, New Haven, Connecticut 06520, New Haven CT, United States
| | - Yogendra Singh
- Department of Zoology, University of Delhi, Faculty of Science, Delhi- 110007, India
- Delhi School of Public Health, Institution of Eminence, University of Delhi, Delhi-110007, India
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Halder U, Mazumder K, Kumar KJ, Bandopadhyay R. Structural insight into a glucomannan-type extracellular polysaccharide produced by a marine Bacillus altitudinis SORB11 from Southern Ocean. Sci Rep 2022; 12:16322. [PMID: 36175467 PMCID: PMC9523031 DOI: 10.1038/s41598-022-20822-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 09/19/2022] [Indexed: 11/09/2022] Open
Abstract
Extracellular polysaccharide (EPS) produced by a deep-sea, psychrotolerant Bacillus altitudinis SORB11 was evaluated by considering physiochemical nature and structural constituents. The productivity of crude EPS was measured ~ 13.17 g L-1. The surface topography of the crude EPS showed a porous, webbed structure along with a branched coil-like configuration. The crystalline crude EPS contained a high amount of sulfur. Further, the crude EPS was subjected for purification. The molecular weight of purified EPS was determined ~ 9.8 × 104 Da. The purified EPS was appeared to show glucomannan-like configuration that is composed of → 4)-β-Manp-(1 → and → 4)-β-Glcp-(1 → residues. So, this polysaccharide was comparable to the structure of plant-derived glucomannan. Subsequently, EPS biosynthesis protein clusters like EpsC, EpsD, EpsE, and glycosyltransferase family proteins were predicted from the genome of strain SORB11, which may provide an insight into the production of glucomannan-type of polysaccharide. This low molecular weight linear form of glucomannan-type EPS might be involved to form a network-like unattached aggregation, and helps in cell-to-cell interaction in deep-sea microbial species.
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Affiliation(s)
- Urmi Halder
- Microbiology Section, Department of Botany, The University of Burdwan, Burdwan, West Bengal, 713104, India
| | - Koushik Mazumder
- National Agri-Food Biotechnology Institute, Sector 81, SAS Nagar, Punjab, 140308, India
| | - K Jayaram Kumar
- Department of Pharmaceutical Sciences and Technology, Birla Institute of Technology, Mesra, Ranchi, Jharkhand, 835215, India
| | - Rajib Bandopadhyay
- Microbiology Section, Department of Botany, The University of Burdwan, Burdwan, West Bengal, 713104, India.
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Dos Santos MC, Tairum CA, Cabrera VIM, Guimarães Cauz AC, Ribeiro LF, Toledo Junior JC, Toyama MH, Lago JHG, Brocchi M, Netto LES, de Oliveira MA. Adenanthin Is an Efficient Inhibitor of Peroxiredoxins from Pathogens, Inhibits Bacterial Growth, and Potentiates Antibiotic Activities. Chem Res Toxicol 2022; 36:570-582. [PMID: 35537067 DOI: 10.1021/acs.chemrestox.2c00049] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The emergence and re-emergence of bacterial strains resistant to multiple drugs represent a global health threat, and the search for novel biological targets is a worldwide concern. AhpC are enzymes involved in bacterial redox homeostasis by metabolizing diverse kinds of hydroperoxides. In pathogenic bacteria, AhpC are related to several functions, as some isoforms are characterized as virulence factors. However, no inhibitor has been systematically evaluated to date. Here we show that the natural ent-kaurane Adenanthin (Adn) efficiently inhibits AhpC and molecular interactions were explored by computer assisted simulations. Additionally, Adn interferes with growth and potentializes the effect of antibiotics (kanamycin and PMBN), positioning Adn as a promising compound to treat infections caused by multiresistant bacterial strains.
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Affiliation(s)
- Melina Cardoso Dos Santos
- Instituto de Biociências, Universidade Estadual Paulista, UNESP, São Vicente, São Paulo 11330-900, Brazil
| | - Carlos Abrunhosa Tairum
- Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, São Paulo, São Paulo 05508-090, Brazil
| | | | - Ana Carolina Guimarães Cauz
- Departamento de Genética, Evolução, Microbiologia e Imunologia, Instituto de Biologia, Universidade Estadual de Campinas, UNICAMP, Campinas, São Paulo 13083-862, Brazil
| | - Luiz Fernando Ribeiro
- Instituto de Biociências, Universidade Estadual Paulista, UNESP, São Vicente, São Paulo 11330-900, Brazil
| | - José Carlos Toledo Junior
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo 14040-901, Brazil
| | - Marcos Hikari Toyama
- Instituto de Biociências, Universidade Estadual Paulista, UNESP, São Vicente, São Paulo 11330-900, Brazil
| | - João Henrique Ghilardi Lago
- Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Santo André, São Paulo 09210-580, Brazil
| | - Marcelo Brocchi
- Departamento de Genética, Evolução, Microbiologia e Imunologia, Instituto de Biologia, Universidade Estadual de Campinas, UNICAMP, Campinas, São Paulo 13083-862, Brazil
| | - Luis Eduardo Soares Netto
- Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, São Paulo, São Paulo 05508-090, Brazil
| | - Marcos Antonio de Oliveira
- Instituto de Biociências, Universidade Estadual Paulista, UNESP, São Vicente, São Paulo 11330-900, Brazil
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Tairum CA, Santos MC, Breyer CA, de Oliveira ALP, Cabrera VIM, Toledo-Silva G, Mori GM, Toyama MH, Netto LES, de Oliveira MA. Effects of Serine or Threonine in the Active Site of Typical 2-Cys Prx on Hyperoxidation Susceptibility and on Chaperone Activity. Antioxidants (Basel) 2021; 10:1032. [PMID: 34202406 PMCID: PMC8300647 DOI: 10.3390/antiox10071032] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 06/02/2021] [Accepted: 06/10/2021] [Indexed: 11/23/2022] Open
Abstract
Typical 2-Cys peroxiredoxins (2-Cys Prx) are ubiquitous Cys-based peroxidases, which are stable as decamers in the reduced state, and may dissociate into dimers upon disulfide bond formation. A peroxidatic Cys (CP) takes part of a catalytic triad, together with a Thr/Ser and an Arg. Previously, we described that the presence of Ser (instead of Thr) in the active site stabilizes yeast 2-Cys Prx as decamers. Here, we compared the hyperoxidation susceptibilities of yeast 2-Cys Prx. Notably, 2-Cys Prx containing Ser (named here Ser-Prx) were more resistant to hyperoxidation than enzymes containing Thr (Thr-Prx). In silico analysis revealed that Thr-Prx are more frequent in all domains of life, while Ser-Prx are more abundant in bacteria. As yeast 2-Cys Prx, bacterial Ser-Prx are more stable as decamers than Thr-Prx. However, bacterial Ser-Prx were only slightly more resistant to hyperoxidation than Thr-Prx. Furthermore, in all cases, organic hydroperoxide inhibited more the peroxidase activities of 2-Cys Prx than hydrogen peroxide. Moreover, bacterial Ser-Prx displayed increased thermal resistance and chaperone activity, which may be related with its enhanced stability as decamers compared to Thr-Prx. Therefore, the single substitution of Thr by Ser in the catalytic triad results in profound biochemical and structural differences in 2-Cys Prx.
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Affiliation(s)
- Carlos A. Tairum
- Instituto de Biociências, Universidade Estadual Paulista, UNESP, São Vicente 01049-010, Brazil; (C.A.T.); (M.C.S.); (C.A.B.); (A.L.P.d.O.); (V.I.M.C.); (M.H.T.)
- Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, São Paulo 01049-010, Brazil
| | - Melina Cardoso Santos
- Instituto de Biociências, Universidade Estadual Paulista, UNESP, São Vicente 01049-010, Brazil; (C.A.T.); (M.C.S.); (C.A.B.); (A.L.P.d.O.); (V.I.M.C.); (M.H.T.)
| | - Carlos Alexandre Breyer
- Instituto de Biociências, Universidade Estadual Paulista, UNESP, São Vicente 01049-010, Brazil; (C.A.T.); (M.C.S.); (C.A.B.); (A.L.P.d.O.); (V.I.M.C.); (M.H.T.)
| | - Ana Laura Pires de Oliveira
- Instituto de Biociências, Universidade Estadual Paulista, UNESP, São Vicente 01049-010, Brazil; (C.A.T.); (M.C.S.); (C.A.B.); (A.L.P.d.O.); (V.I.M.C.); (M.H.T.)
| | - Vitoria Isabela Montanhero Cabrera
- Instituto de Biociências, Universidade Estadual Paulista, UNESP, São Vicente 01049-010, Brazil; (C.A.T.); (M.C.S.); (C.A.B.); (A.L.P.d.O.); (V.I.M.C.); (M.H.T.)
| | - Guilherme Toledo-Silva
- Laboratório de Biomarcadores de Contaminação Aquática e Imunoquímica, Departamento de Bioquímica, Universidade Federal de Santa Catarina, Florianópolis 88040-900, Brazil;
| | - Gustavo Maruyama Mori
- Laboratório de Ecologia Molecular, Instituto de Biociências, Universidade Estadual Paulista, UNESP, São Vicente 01049-010, Brazil;
| | - Marcos Hikari Toyama
- Instituto de Biociências, Universidade Estadual Paulista, UNESP, São Vicente 01049-010, Brazil; (C.A.T.); (M.C.S.); (C.A.B.); (A.L.P.d.O.); (V.I.M.C.); (M.H.T.)
| | - Luis Eduardo Soares Netto
- Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, São Paulo 01049-010, Brazil
| | - Marcos Antonio de Oliveira
- Instituto de Biociências, Universidade Estadual Paulista, UNESP, São Vicente 01049-010, Brazil; (C.A.T.); (M.C.S.); (C.A.B.); (A.L.P.d.O.); (V.I.M.C.); (M.H.T.)
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Sharipova MR, Mardanova AM, Rudakova NL, Pudova DS. Bistability and Formation of the Biofilm Matrix as Adaptive Mechanisms during the Stationary Phase of Bacillus subtilis. Microbiology (Reading) 2021. [DOI: 10.1134/s002626172006017x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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Bacillus velezensis Wall Teichoic Acids Are Required for Biofilm Formation and Root Colonization. Appl Environ Microbiol 2019; 85:AEM.02116-18. [PMID: 30552189 DOI: 10.1128/aem.02116-18] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 12/03/2018] [Indexed: 12/21/2022] Open
Abstract
Rhizosphere colonization by plant growth-promoting rhizobacteria (PGPR) along plant roots facilitates the ability of PGPR to promote plant growth and health. Thus, an understanding of the molecular mechanisms of the root colonization process by plant-beneficial Bacillus strains is essential for the use of these strains in agriculture. Here, we observed that an sfp gene mutant of the plant growth-promoting rhizobacterium Bacillus velezensis SQR9 was unable to form normal biofilm architecture, and differential protein expression was observed by proteomic analysis. A minor wall teichoic acid (WTA) biosynthetic protein, GgaA, was decreased over 4-fold in the Δsfp mutant, and impairment of the ggaA gene postponed biofilm formation and decreased cucumber root colonization capabilities. In addition, we provide evidence that the major WTA biosynthetic enzyme GtaB is involved in both biofilm formation and root colonization. The deficiency in biofilm formation of the ΔgtaB mutant may be due to an absence of UDP-glucose, which is necessary for the synthesis of biofilm matrix exopolysaccharides (EPS). These observations provide insights into the root colonization process by a plant-beneficial Bacillus strain, which will help improve its application as a biofertilizer.IMPORTANCE Bacillus velezensis is a Gram-positive plant-beneficial bacterium which is widely used in agriculture. Additionally, Bacillus spp. are some of the model organisms used in the study of biofilms, and as such, the molecular networks and regulation systems of biofilm formation are well characterized. However, the molecular processes involved in root colonization by plant-beneficial Bacillus strains remain largely unknown. Here, we showed that WTAs play important roles in the plant root colonization process. The loss of the gtaB gene affects the ability of B. velezensis SQR9 to sense plant polysaccharides, which are important environmental cues that trigger biofilm formation and colonization in the rhizosphere. This knowledge provides new insights into the Bacillus root colonization process and can help improve our understanding of plant-rhizobacterium interactions.
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Grimm I, Dumke J, Dreier J, Knabbe C, Vollmer T. Biofilm formation and transcriptome analysis of Streptococcus gallolyticus subsp. gallolyticus in response to lysozyme. PLoS One 2018; 13:e0191705. [PMID: 29373594 PMCID: PMC5786311 DOI: 10.1371/journal.pone.0191705] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 01/10/2018] [Indexed: 02/06/2023] Open
Abstract
Streptococcus gallolyticus subsp. gallolyticus is a commensal bacterium of the human gastrointestinal tract, and a pathogen causing infective endocarditis and other biofilm-associated infections via exposed collagen. This study focuses on the characterization of the biofilm formation and collagen adhesion of S. gallolyticus subsp. gallolyticus under different conditions. In this study, it has been observed that the isolate UCN 34 is resistant to 20 mg/ml lysozyme in BHI medium, whereas the strain BAA-2069 builds more biofilm in the presence of lysozyme compared to in a control of BHI without lysozyme. A transcriptome analysis with whole genome microarrays of these two isolates in BHI medium with lysozyme compared to control without lysozyme revealed changes in gene expression levels. In the isolate BAA-2069, 67 genes showed increased expression in the presence of lysozyme, while in the isolate UCN 34, 165 genes showed increased expression and 30 genes showed decreased expression through lysozyme treatment. Products of genes which were higher expressed are in involved in transcription and translation, in cell-wall modification, in hydrogen peroxide resistance and in bacterial immunity. Furthermore, the adhesion ability of different strains of S. gallolyticus subsp. gallolyticus to collagen type I and IV was analyzed. Thereby, we compared the adhesion of 46 human isolates with 23 isolates from animals. It was shown that the adhesion ability depends significantly on whether the isolate was isolated from human or animal. For example, high adhesion ability was observed for strain UCN 34 isolated from an infective endocarditis patient, whereas strain DSM 16831 isolated from koala feces adhered only marginally to collagen. Full genome microarray analysis of these two strains revealed strain-dependent gene expression due to adhesion. The expression of 25 genes of a transposon and 15 genes of a phage region in strain DSM 16831 were increased, which corresponds to horizontal gene transfer. Adherence to collagen in strain UCN 34 led to higher expression of 27 genes and lower expression of 31 genes. This was suggestive of a change in nutrient uptake.
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Affiliation(s)
- Imke Grimm
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinikum der Ruhr-Universität Bochum, Bad Oeynhausen, Germany
| | - Jessika Dumke
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinikum der Ruhr-Universität Bochum, Bad Oeynhausen, Germany
| | - Jens Dreier
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinikum der Ruhr-Universität Bochum, Bad Oeynhausen, Germany
| | - Cornelius Knabbe
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinikum der Ruhr-Universität Bochum, Bad Oeynhausen, Germany
| | - Tanja Vollmer
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinikum der Ruhr-Universität Bochum, Bad Oeynhausen, Germany
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Zwick JV, Noble S, Ellaicy YK, Coe GD, Hakey DJ, King AN, Sadauskas AJ, Faulkner MJ. AhpA is a peroxidase expressed during biofilm formation in Bacillus subtilis. Microbiologyopen 2016; 6. [PMID: 27683249 PMCID: PMC5300871 DOI: 10.1002/mbo3.403] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Revised: 08/17/2016] [Accepted: 08/23/2016] [Indexed: 11/10/2022] Open
Abstract
Organisms growing aerobically generate reactive oxygen species such as hydrogen peroxide. These reactive oxygen molecules damage enzymes and DNA, potentially causing cell death. In response, Bacillus subtilis produces at least nine potential peroxide-scavenging enzymes; two belong to the alkylhydroperoxide reductase (Ahp) class of peroxidases. Here, we explore the role of one of these Ahp homologs, AhpA. While previous studies demonstrated that AhpA can scavenge peroxides and thus defend cells against peroxides, they did not clarify when during growth the cell produces AhpA. The results presented here show that the expression of ahpA is regulated in a manner distinct from that of the other peroxide-scavenging enzymes in B. subtilis. While the primary Ahp, AhpC, is expressed during exponential growth and stationary phase, these studies demonstrate that the expression of ahpA is dependent on the transition-state regulator AbrB and the sporulation and biofilm formation transcription factor Spo0A. Furthermore, these results show that ahpA is specifically expressed during biofilm formation, and not during sporulation or stationary phase, suggesting that derepression of ahpA by AbrB requires a signal other than those present upon entry into stationary phase. Despite this expression pattern, ahpA mutant strains still form and maintain robust biofilms, even in the presence of peroxides. Thus, the role of AhpA with regard to protecting cells within biofilms from environmental stresses is still uncertain. These studies highlight the need to further study the Ahp homologs to better understand how they differ from one another and the unique roles they may play in oxidative stress resistance.
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Affiliation(s)
- Joelie V Zwick
- Department of Biology, Bradley University, Peoria, IL, USA
| | - Sarah Noble
- Department of Biology, Bradley University, Peoria, IL, USA
| | | | | | - Dylan J Hakey
- Department of Biology, Bradley University, Peoria, IL, USA
| | - Alyssa N King
- Department of Biology, Bradley University, Peoria, IL, USA
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