1
|
Yang X, Zeng J, Wang D, Zhou Q, Yu X, Wang Z, Bai T, Luan G, Xu Y. NagZ modulates the virulence of E. cloacae by acting through the gene of unknown function, ECL_03795. Virulence 2024; 15:2367652. [PMID: 38912723 PMCID: PMC11197897 DOI: 10.1080/21505594.2024.2367652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Accepted: 06/09/2024] [Indexed: 06/25/2024] Open
Abstract
β-N-acetylglucosaminidase (NagZ), a cytosolic glucosaminidase, plays a pivotal role in peptidoglycan recycling. Previous research demonstrated that NagZ knockout significantly eradicated AmpC-dependent β-lactam resistance in Enterobacter cloacae. However, NagZ's role in the virulence of E. cloacae remains unclear. Our study, incorporating data on mouse and Galleria mellonella larval mortality rates, inflammation markers, and histopathological examinations, revealed a substantial reduction in the virulence of E. cloacae following NagZ knockout. Transcriptome sequencing uncovered differential gene expression between NagZ knockout and wild-type strains, particularly in nucleotide metabolism pathways. Further investigation demonstrated that NagZ deletion led to a significant increase in cyclic diguanosine monophosphate (c-di-GMP) levels. Additionally, transcriptome sequencing and RT-qPCR confirmed significant differences in the expression of ECL_03795, a gene with an unknown function but speculated to be involved in c-di-GMP metabolism due to its EAL domain known for phosphodiesterase activity. Interestingly, in ECL_03795 knockout strains, a notable reduction in the virulence was observed, and virulence was rescued upon complementation with ECL_03795. Consequently, our study suggests that NagZ's function on virulence is partially mediated through the ECL_03795→c-di-GMP pathway, providing insight into the development of novel therapies and strongly supporting the interest in creating highly efficient NagZ inhibitors.
Collapse
Affiliation(s)
- Xianggui Yang
- Department of Laboratory Medicine, Clinical Medical College and the First Affiliated Hospital of Chengdu Medical College, Chengdu, Sichuan, China
| | - Jun Zeng
- Division of Pulmonary and Critical Care Medicine, Clinical Medical College and the First Affiliated Hospital of Chengdu Medical College, Chengdu, Sichuan, China
| | - Dan Wang
- Department of Laboratory Medicine, Clinical Medical College and the First Affiliated Hospital of Chengdu Medical College, Chengdu, Sichuan, China
| | - Qin Zhou
- Department of Laboratory Medicine, Clinical Medical College and the First Affiliated Hospital of Chengdu Medical College, Chengdu, Sichuan, China
| | - Xuejing Yu
- Department of Internal Medicine, Division of Cardiology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Zhenguo Wang
- Department of Stomatology, Clinical Medical College and the First Affiliated Hospital of Chengdu Medical College, Chengdu, Sichuan, China
| | - Tingting Bai
- Department of Laboratory Medicine, Clinical Medical College and the First Affiliated Hospital of Chengdu Medical College, Chengdu, Sichuan, China
| | - Guangxin Luan
- Department of Laboratory Medicine, Clinical Medical College and the First Affiliated Hospital of Chengdu Medical College, Chengdu, Sichuan, China
| | - Ying Xu
- Department of Laboratory Medicine, Clinical Medical College and the First Affiliated Hospital of Chengdu Medical College, Chengdu, Sichuan, China
| |
Collapse
|
2
|
Li R, Yang P, Zhang H, Wang C, Zhao F, Liu J, Wang Y, Liang Y, Sun T, Xie X. Comparative Genomic and Functional Analysis of c-di-GMP Metabolism and Regulatory Proteins in Bacillus velezensis LQ-3. Microorganisms 2024; 12:1724. [PMID: 39203566 PMCID: PMC11357230 DOI: 10.3390/microorganisms12081724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2024] [Revised: 08/08/2024] [Accepted: 08/16/2024] [Indexed: 09/03/2024] Open
Abstract
Bacillus velezensis is a promising candidate for biocontrol applications. A common second messenger molecule, bis-(3,5)-cyclic-dimeric-guanosine monophosphate (c-di-GMP), has the ability to regulate a range of physiological functions that impact the effectiveness of biocontrol. However, the status of the c-di-GMP signaling pathway in biocontrol strain LQ-3 remains unknown. Strain LQ-3, which was isolated from wheat rhizosphere soil, has shown effective control of wheat sharp eyespot and has been identified as B. velezensis through whole-genome sequencing analyses. In this study, we investigated the intracellular c-di-GMP signaling pathway of LQ-3 and further performed a comparative genomic analysis of LQ-3 and 29 other B. velezensis strains. The results revealed the presence of four proteins containing the GGDEF domain, which is the conserved domain for c-di-GMP synthesis enzymes. Additionally, two proteins were identified with the EAL domain, which represents the conserved domain for c-di-GMP degradation enzymes. Furthermore, one protein was found to possess a PilZ domain, indicative of the conserved domain for c-di-GMP receptors in LQ-3. These proteins are called DgcK, DgcP, YybT, YdaK, PdeH, YkuI, and DgrA, respectively; they are distributed in a similar manner across the strains and belong to the signal transduction family. We selected five genes from the aforementioned seven genes for further study, excluding YybT and DgrA. They all play a role in regulating the motility, biofilm formation, and colonization of LQ-3. This study reveals the c-di-GMP signaling pathway associated with biocontrol features in B. velezensis LQ-3, providing guidance for the prevention and control of wheat sharp eyespot by LQ-3.
Collapse
Affiliation(s)
- Rong Li
- Institute of Wheat Research, Shanxi Agricultural University, Linfen 041000, China; (R.L.); (H.Z.); (C.W.); (F.Z.); (J.L.); (Y.W.); (Y.L.); (T.S.)
| | - Panlei Yang
- Department of Plant Pathology, College of Plant Protection, China Agricultural University, Beijing 100193, China;
| | - Hongjuan Zhang
- Institute of Wheat Research, Shanxi Agricultural University, Linfen 041000, China; (R.L.); (H.Z.); (C.W.); (F.Z.); (J.L.); (Y.W.); (Y.L.); (T.S.)
| | - Chunjing Wang
- Institute of Wheat Research, Shanxi Agricultural University, Linfen 041000, China; (R.L.); (H.Z.); (C.W.); (F.Z.); (J.L.); (Y.W.); (Y.L.); (T.S.)
| | - Fang Zhao
- Institute of Wheat Research, Shanxi Agricultural University, Linfen 041000, China; (R.L.); (H.Z.); (C.W.); (F.Z.); (J.L.); (Y.W.); (Y.L.); (T.S.)
| | - Jiehui Liu
- Institute of Wheat Research, Shanxi Agricultural University, Linfen 041000, China; (R.L.); (H.Z.); (C.W.); (F.Z.); (J.L.); (Y.W.); (Y.L.); (T.S.)
| | - Yanbin Wang
- Institute of Wheat Research, Shanxi Agricultural University, Linfen 041000, China; (R.L.); (H.Z.); (C.W.); (F.Z.); (J.L.); (Y.W.); (Y.L.); (T.S.)
| | - Yan Liang
- Institute of Wheat Research, Shanxi Agricultural University, Linfen 041000, China; (R.L.); (H.Z.); (C.W.); (F.Z.); (J.L.); (Y.W.); (Y.L.); (T.S.)
| | - Ting Sun
- Institute of Wheat Research, Shanxi Agricultural University, Linfen 041000, China; (R.L.); (H.Z.); (C.W.); (F.Z.); (J.L.); (Y.W.); (Y.L.); (T.S.)
| | - Xiansheng Xie
- Institute of Wheat Research, Shanxi Agricultural University, Linfen 041000, China; (R.L.); (H.Z.); (C.W.); (F.Z.); (J.L.); (Y.W.); (Y.L.); (T.S.)
| |
Collapse
|
3
|
Liu L, Luo D, Zhang Y, Liu D, Yin K, Tang Q, Chou SH, He J. Characterization of the dual regulation by a c-di-GMP riboswitch Bc1 with a long expression platform from Bacillus thuringiensis. Microbiol Spectr 2024; 12:e0045024. [PMID: 38819160 PMCID: PMC11218506 DOI: 10.1128/spectrum.00450-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Accepted: 04/29/2024] [Indexed: 06/01/2024] Open
Abstract
A riboswitch generally regulates the expression of its downstream genes through conformational change in its expression platform (EP) upon ligand binding. The cyclic diguanosine monophosphate (c-di-GMP) class I riboswitch Bc1 is widespread and conserved among Bacillus cereus group species. In this study, we revealed that Bc1 has a long EP with two typical ρ-independent terminator sequences 28 bp apart. The upstream terminator T1 is dominant in vitro, while downstream terminator T2 is more efficient in vivo. Through mutation analysis, we elucidated that Bc1 exerts a rare and incoherent "transcription-translation" dual regulation with T2 playing a crucial role. However, we found that Bc1 did not respond to c-di-GMP under in vitro transcription conditions, and the expressions of downstream genes did not change with fluctuation in intracellular c-di-GMP concentration. To explore this puzzle, we conducted SHAPE-MaP and confirmed the interaction of Bc1 with c-di-GMP. This shows that as c-di-GMP concentration increases, T1 unfolds but T2 remains almost intact and functional. The presence of T2 masks the effect of T1 unwinding, resulting in no response of Bc1 to c-di-GMP. The high Shannon entropy values of EP region imply the potential alternative structures of Bc1. We also found that zinc uptake regulator can specifically bind to the dual terminator coding sequence and slightly trigger the response of Bc1 to c-di-GMP. This work will shed light on the dual-regulation riboswitch and enrich our understanding of the RNA world.IMPORTANCEIn nature, riboswitches are involved in a variety of metabolic regulation, most of which preferentially regulate transcription termination or translation initiation of downstream genes in specific ways. Alternatively, the same or different riboswitches can exist in tandem to enhance regulatory effects or respond to multiple ligands. However, many putative conserved riboswitches have not yet been experimentally validated. Here, we found that the c-di-GMP riboswitch Bc1 with a long EP could form a dual terminator and exhibit non-canonical and incoherent "transcription-translation" dual regulation. Besides, zinc uptake regulator specifically bound to the coding sequence of the Bc1 EP and slightly mediated the action of Bc1. The application of SHAPE-MaP to the dual regulation mechanism of Bc1 may establish the foundation for future studies of such complex untranslated regions in other bacterial genomes.
Collapse
Affiliation(s)
- Lu Liu
- National Key Laboratory of Agricultural Microbiology & Hubei Hongshan Laboratory, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Dehua Luo
- National Key Laboratory of Agricultural Microbiology & Hubei Hongshan Laboratory, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Yongji Zhang
- National Key Laboratory of Agricultural Microbiology & Hubei Hongshan Laboratory, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Dingqi Liu
- National Key Laboratory of Agricultural Microbiology & Hubei Hongshan Laboratory, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Kang Yin
- National Key Laboratory of Agricultural Microbiology & Hubei Hongshan Laboratory, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Qing Tang
- National Key Laboratory of Agricultural Microbiology & Hubei Hongshan Laboratory, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Shan-Ho Chou
- National Key Laboratory of Agricultural Microbiology & Hubei Hongshan Laboratory, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Jin He
- National Key Laboratory of Agricultural Microbiology & Hubei Hongshan Laboratory, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| |
Collapse
|
4
|
Le S, Wei L, Wang J, Tian F, Yang Q, Zhao J, Zhong Z, Liu J, He X, Zhong Q, Lu S, Liang H. Bacteriophage protein Dap1 regulates evasion of antiphage immunity and Pseudomonas aeruginosa virulence impacting phage therapy in mice. Nat Microbiol 2024; 9:1828-1841. [PMID: 38886583 DOI: 10.1038/s41564-024-01719-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Accepted: 04/30/2024] [Indexed: 06/20/2024]
Abstract
Bacteriophages have evolved diverse strategies to overcome host defence mechanisms and to redirect host metabolism to ensure successful propagation. Here we identify a phage protein named Dap1 from Pseudomonas aeruginosa phage PaoP5 that both modulates bacterial host behaviour and contributes to phage fitness. We show that expression of Dap1 in P. aeruginosa reduces bacterial motility and promotes biofilm formation through interference with DipA, a c-di-GMP phosphodiesterase, which causes an increase in c-di-GMP levels that trigger phenotypic changes. Results also show that deletion of dap1 in PaoP5 significantly reduces genome packaging. In this case, Dap1 directly binds to phage HNH endonuclease, prohibiting host Lon-mediated HNH degradation and promoting phage genome packaging. Moreover, PaoP5Δdap1 fails to rescue P. aeruginosa-infected mice, implying the significance of dap1 in phage therapy. Overall, these results highlight remarkable dual functionality in a phage protein, enabling the modulation of host behaviours and ensuring phage fitness.
Collapse
Affiliation(s)
- Shuai Le
- Department of Microbiology, College of Basic Medical Sciences, Key Laboratory of Microbial Engineering Under the Educational Committee in Chongqing, Army Medical University, Chongqing, China
- State Key Laboratory of Trauma and Chemical Poisoning, Chongqing, China
| | - Leilei Wei
- Department of Laboratory Medicine, Daping Hospital, Army Medical University, Chongqing, China
- College of Medicine, Southern University of Science and Technology, Shenzhen, China
| | - Jing Wang
- Department of Microbiology, College of Basic Medical Sciences, Key Laboratory of Microbial Engineering Under the Educational Committee in Chongqing, Army Medical University, Chongqing, China
- State Key Laboratory of Trauma and Chemical Poisoning, Chongqing, China
| | - Fang Tian
- College of Medicine, Southern University of Science and Technology, Shenzhen, China
| | - Qian Yang
- College of Life Sciences, Northwest University, Xi'an, China
| | - Jingru Zhao
- College of Life Sciences, Northwest University, Xi'an, China
| | - Zhuojun Zhong
- Department of Microbiology, College of Basic Medical Sciences, Key Laboratory of Microbial Engineering Under the Educational Committee in Chongqing, Army Medical University, Chongqing, China
- State Key Laboratory of Trauma and Chemical Poisoning, Chongqing, China
| | - Jiazhen Liu
- Department of Microbiology, College of Basic Medical Sciences, Key Laboratory of Microbial Engineering Under the Educational Committee in Chongqing, Army Medical University, Chongqing, China
- State Key Laboratory of Trauma and Chemical Poisoning, Chongqing, China
| | - Xuesong He
- The ADA Forsyth Institute, Cambridge, MA, USA
| | - Qiu Zhong
- Department of Laboratory Medicine, Daping Hospital, Army Medical University, Chongqing, China
| | - Shuguang Lu
- Department of Microbiology, College of Basic Medical Sciences, Key Laboratory of Microbial Engineering Under the Educational Committee in Chongqing, Army Medical University, Chongqing, China
- State Key Laboratory of Trauma and Chemical Poisoning, Chongqing, China
| | - Haihua Liang
- College of Medicine, Southern University of Science and Technology, Shenzhen, China.
- University Laboratory of Metabolism and Health of Guangdong, Southern University of Science and Technology, Shenzhen, China.
| |
Collapse
|
5
|
Zhan X, Zhang K, Wang C, Fan Q, Tang X, Zhang X, Wang K, Fu Y, Liang H. A c-di-GMP signaling module controls responses to iron in Pseudomonas aeruginosa. Nat Commun 2024; 15:1860. [PMID: 38424057 PMCID: PMC10904736 DOI: 10.1038/s41467-024-46149-3] [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: 10/28/2023] [Accepted: 02/15/2024] [Indexed: 03/02/2024] Open
Abstract
Cyclic dimeric guanosine monophosphate (c-di-GMP) serves as a bacterial second messenger that modulates various processes including biofilm formation, motility, and host-microbe symbiosis. Numerous studies have conducted comprehensive analysis of c-di-GMP. However, the mechanisms by which certain environmental signals such as iron control intracellular c-di-GMP levels are unclear. Here, we show that iron regulates c-di-GMP levels in Pseudomonas aeruginosa by modulating the interaction between an iron-sensing protein, IsmP, and a diguanylate cyclase, ImcA. Binding of iron to the CHASE4 domain of IsmP inhibits the IsmP-ImcA interaction, which leads to increased c-di-GMP synthesis by ImcA, thus promoting biofilm formation and reducing bacterial motility. Structural characterization of the apo-CHASE4 domain and its binding to iron allows us to pinpoint residues defining its specificity. In addition, the cryo-electron microscopy structure of ImcA in complex with a c-di-GMP analog (GMPCPP) suggests a unique conformation in which the compound binds to the catalytic pockets and to the membrane-proximal side located at the cytoplasm. Thus, our results indicate that a CHASE4 domain directly senses iron and modulates the crosstalk between c-di-GMP metabolic enzymes.
Collapse
Affiliation(s)
- Xueliang Zhan
- College of Life Sciences, Northwest University, Xi'an, ShaanXi, China
| | - Kuo Zhang
- College of Medicine, Southern University of Science and Technology, Shenzhen, China
| | - Chenchen Wang
- College of Medicine, Southern University of Science and Technology, Shenzhen, China
| | - Qiao Fan
- College of Life Sciences, Northwest University, Xi'an, ShaanXi, China
| | - Xiujia Tang
- Department of Pulmonary and Critical Care Medicine, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
| | - Xi Zhang
- College of Life Sciences, Northwest University, Xi'an, ShaanXi, China
| | - Ke Wang
- Department of Pulmonary and Critical Care Medicine, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
| | - Yang Fu
- College of Medicine, Southern University of Science and Technology, Shenzhen, China
| | - Haihua Liang
- College of Medicine, Southern University of Science and Technology, Shenzhen, China.
- University Laboratory of Metabolism and Health of Guangdong, Southern University of Science and Technology, Shenzhen, China.
| |
Collapse
|
6
|
Feng Q, Zhou J, Zhang L, Fu Y, Yang L. Insights into the molecular basis of c-di-GMP signalling in Pseudomonas aeruginosa. Crit Rev Microbiol 2024; 50:20-38. [PMID: 36539391 DOI: 10.1080/1040841x.2022.2154140] [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: 08/29/2022] [Accepted: 11/25/2022] [Indexed: 12/24/2022]
Abstract
The opportunistic human pathogen Pseudomonas aeruginosa can cause severe infections in immunocompromized people or cystic fibrosis (CF) patients. Because of its remarkable ability to invade the host and withstand the bacteriocidal effect of most conventional antibiotics, the infection caused by P. aeruginosa has become a major concern for human health. The switch from acute to chronic infection is governed by the second messenger bis-(3'-5')-cyclic dimeric guanosine mono-phosphate (c-di-GMP) in P. aeruginosa, and c-di-GMP is now recognized to regulate many important biological processes in pathogenesis. The c-di-GMP signalling mechanisms in P. aeruginosa have been studied extensively in the past decade, revealing complicated c-di-GMP metabolism and signalling network. In this review, the underlying mechanisms of this signalling network will be discussed, mainly focussing on how environmental cues regulate c-di-GMP signalling, protein-protein interaction mediated functional regulation, heterogeneity of c-di-GMP and cross talk between c-di-GMP signalling and other signalling systems. Understanding the molecular mechanism underlying the complex c-di-GMP signalling network would be beneficial for developing therapeutic approaches and antibacterial agents to combat the threat from P. aeruginosa.
Collapse
Affiliation(s)
- Qishun Feng
- School of Medicine, Southern University of Science and Technology, Shenzhen, PR China
| | - Jianuan Zhou
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, PR China
- Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, PR China
| | - Lianhui Zhang
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, PR China
- Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, PR China
| | - Yang Fu
- School of Medicine, Southern University of Science and Technology, Shenzhen, PR China
| | - Liang Yang
- School of Medicine, Southern University of Science and Technology, Shenzhen, PR China
| |
Collapse
|
7
|
Meireles D, Pombinho R, Cabanes D. Signals behind Listeria monocytogenes virulence mechanisms. Gut Microbes 2024; 16:2369564. [PMID: 38979800 PMCID: PMC11236296 DOI: 10.1080/19490976.2024.2369564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Accepted: 06/13/2024] [Indexed: 07/10/2024] Open
Abstract
The tight and coordinated regulation of virulence gene expression is crucial to ensure the survival and persistence of bacterial pathogens in different contexts within their hosts. Considering this, bacteria do not express virulence factors homogenously in time and space, either due to their associated fitness cost or to their detrimental effect at specific infection stages. To efficiently infect and persist into their hosts, bacteria have thus to monitor environmental cues or chemical cell-to-cell signaling mechanisms that allow their transition from the external environment to the host, and therefore adjust gene expression levels, intrinsic biological activities, and appropriate behaviors. Listeria monocytogenes (Lm), a major Gram-positive facultative intracellular pathogen, stands out for its adaptability and capacity to thrive in a wide range of environments. Because of that, Lm presents itself as a significant concern in food safety and public health, that can lead to potentially life-threatening infections in humans. A deeper understanding of the intricate bacterial virulence mechanisms and the signals that control them provide valuable insights into the dynamic interplay between Lm and the host. Therefore, this review addresses the role of some crucial signals behind Lm pathogenic virulence mechanisms and explores how the ability to assimilate and interpret these signals is fundamental for pathogenesis, identifying potential targets for innovative antimicrobial strategies.
Collapse
Affiliation(s)
- Diana Meireles
- Instituto de Investigação e Inovação em Saúde, Porto, Portugal
- Group of Molecular Microbiology, IBMC, Porto, Portugal
- Instituto de Ciências Biomédicas Abel Salazar – ICBAS, Porto, Portugal
| | - Rita Pombinho
- Instituto de Investigação e Inovação em Saúde, Porto, Portugal
- Group of Molecular Microbiology, IBMC, Porto, Portugal
| | - Didier Cabanes
- Instituto de Investigação e Inovação em Saúde, Porto, Portugal
- Group of Molecular Microbiology, IBMC, Porto, Portugal
| |
Collapse
|
8
|
Chen T, Pu M, Subramanian S, Kearns D, Rowe-Magnus D. PlzD modifies Vibrio vulnificus foraging behavior and virulence in response to elevated c-di-GMP. mBio 2023; 14:e0153623. [PMID: 37800901 PMCID: PMC10653909 DOI: 10.1128/mbio.01536-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Accepted: 08/21/2023] [Indexed: 10/07/2023] Open
Abstract
IMPORTANCE Many free-swimming bacteria propel themselves through liquid using rotary flagella, and mounting evidence suggests that the inhibition of flagellar rotation initiates biofilm formation, a sessile lifestyle that is a nearly universal surface colonization paradigm in bacteria. In general, motility and biofilm formation are inversely regulated by the intracellular second messenger bis-(3´-5´)-cyclic dimeric guanosine monophosphate (c-di-GMP). Here, we identify a protein, PlzD, bearing a conserved c-di-GMP binding PilZ domain that localizes to the flagellar pole in a c-di-GMP-dependent manner and alters the foraging behavior, biofilm, and virulence characteristics of the opportunistic human pathogen, Vibrio vulnificus. Our data suggest that PlzD interacts with components of the flagellar stator to decrease bacterial swimming speed and changes in swimming direction, and these activities are enhanced when cellular c-di-GMP levels are elevated. These results reveal a physical link between a second messenger (c-di-GMP) and an effector (PlzD) that promotes transition from a motile to a sessile state in V. vulnificus.
Collapse
Affiliation(s)
- Tianyi Chen
- Department of Biology, Indiana University Bloomington, Bloomington, Indiana, USA
| | - Meng Pu
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota, USA
| | - Sundharraman Subramanian
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA
| | - Dan Kearns
- Department of Biology, Indiana University Bloomington, Bloomington, Indiana, USA
| | - Dean Rowe-Magnus
- Department of Biology, Indiana University Bloomington, Bloomington, Indiana, USA
- Department of Molecular and Cellular Biochemistry, Indiana University Bloomington, Bloomington, Indiana, USA
| |
Collapse
|
9
|
Khan F, Jeong GJ, Tabassum N, Kim YM. Functional diversity of c-di-GMP receptors in prokaryotic and eukaryotic systems. Cell Commun Signal 2023; 21:259. [PMID: 37749602 PMCID: PMC10519070 DOI: 10.1186/s12964-023-01263-5] [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: 06/21/2023] [Accepted: 08/09/2023] [Indexed: 09/27/2023] Open
Abstract
Cyclic bis-(3', 5')-dimeric guanosine monophosphate (c-di-GMP) is ubiquitous in many bacterial species, where it functions as a nucleotide-based secondary messenger and is a vital regulator of numerous biological processes. Due to its ubiquity, most bacterial species possess a wide range of downstream receptors that has a binding affinity to c-di-GMP and elicit output responses. In eukaryotes, several enzymes and riboswitches operate as receptors that interact with c-di-GMP and transduce cellular or environmental signals. This review examines the functional variety of receptors in prokaryotic and eukaryotic systems that exhibit distinct biological responses after interacting with c-di-GMP. Evolutionary relationships and similarities in distance among the c-di-GMP receptors in various bacterial species were evaluated to understand their specificities. Furthermore, residues of receptors involved in c-di-GMP binding are summarized. This review facilitates the understanding of how distinct receptors from different origins bind c-di-GMP equally well, yet fulfill diverse biological roles at the interspecies, intraspecies, and interkingdom levels. Furthermore, it also highlights c-di-GMP receptors as potential therapeutic targets, particularly those found in pathogenic microorganisms. Video Abstract.
Collapse
Affiliation(s)
- Fazlurrahman Khan
- Marine Integrated Biomedical Technology Center, The National Key Research Institutes in Universities, Pukyong National University, Busan, 48513, Republic of Korea.
- Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan, 48513, Republic of Korea.
| | - Geum-Jae Jeong
- Department of Food Science and Technology, Pukyong National University, Busan, 48513, Republic of Korea
| | - Nazia Tabassum
- Marine Integrated Biomedical Technology Center, The National Key Research Institutes in Universities, Pukyong National University, Busan, 48513, Republic of Korea
- Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan, 48513, Republic of Korea
| | - Young-Mog Kim
- Marine Integrated Biomedical Technology Center, The National Key Research Institutes in Universities, Pukyong National University, Busan, 48513, Republic of Korea.
- Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan, 48513, Republic of Korea.
- Department of Food Science and Technology, Pukyong National University, Busan, 48513, Republic of Korea.
| |
Collapse
|
10
|
Dodan H, Hiromura M, Ting Ni R, Matsubara F, Kuroda T, Ogawa W. Mutation in crrB encoding a sensor kinase increases expression of the RND-type multidrug efflux pump KexD in Klebsiella pneumoniae. Gene 2023:147543. [PMID: 37331490 DOI: 10.1016/j.gene.2023.147543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 05/23/2023] [Accepted: 06/02/2023] [Indexed: 06/20/2023]
Abstract
BACKGROUND RND-type multidrug efflux systems in Gram-negative bacteria protect them against antimicrobial agents. Gram-negative bacteria generally possess several genes which encode such efflux pumps, but these pumps sometimes fail to show expression. Generally, some multidrug efflux pumps are silent or expressed only at low levels. However, genome mutations often increase the expression of such genes, conferring the bacteria with multidrug-resistant phenotypes. We previously reported mutants with increased expression of the multidrug efflux pump KexD. We aimed to identify the cause of KexD overexpression in our isolates. Furthermore, we also examined the colistin resistant levels in our mutants. METHODS A transposon (Tn) was inserted into the genome of Klebsiella pneumoniae Em16-1, a KexD-overexpressing mutant, to identify the gene(s) responsible for KexD overexpression. RESULTS Thirty-two strains with decreased kexD expression after Tn insertion were isolated. In 12 of these 32 strains, Tn was identified in crrB, which encodes a sensor kinase of a two-component regulatory system. DNA sequencing of crrB in Em16-1 showed that the 452nd cytosine on crrB was replaced by thymine, and this mutation changed the 151st proline into leucine. The same mutation was found in all other KexD-overexpressing mutants. The expression of crrA increased in the mutant overexpressing kexD, and the strains in which crrA was complemented by a plasmid showed elevated expression of kexD and crrB from the genome. The complementation of the mutant-type crrB also increased the expression of kexD and crrA from the genome, but the complementation of the wild-type crrB did not. Deletion of crrB decreased antibiotic resistance levels and KexD expression. CrrB was reported as a factor of colistin resistance, and the colistin resistance of our strains was tested. However, our mutants and strains carrying kexD on a plasmid did not show increased colistin resistance. CONCLUSION Mutation in crrB is important for KexD overexpression. Increased CrrA may also be associated with KexD overexpression.
Collapse
Affiliation(s)
- Hayata Dodan
- Department of Microbiology, Faculty of Pharmaceutical Sciences, Okayama University, Tsushima, Kita-ku, Okayama 700-8530, Japan
| | - Makoto Hiromura
- Department of Molecular Biology, Daiichi University of Pharmacy, Tamagawa-machi, Minami-ku, Fukuoka 815-8511, Japan
| | - Rui Ting Ni
- Department of Microbiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Tsushima, Kita-ku, Okayama 700-8530, Japan
| | - Futoshi Matsubara
- Department of Microbiology and Biochemistry, Daiichi University of Pharmacy, Tamagawa-machi, Minami-ku, Fukuoka 815-8511, Japan
| | - Teruo Kuroda
- Department of Microbiology, Faculty of Pharmaceutical Sciences, Okayama University, Tsushima, Kita-ku, Okayama 700-8530, Japan; Department of Microbiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Tsushima, Kita-ku, Okayama 700-8530, Japan; Department of Microbiology, Graduate School of Biomedical & Health Sciences, Hiroshima University, Kasumi, Minami-ku, Hiroshima 734-8553, Japan
| | - Wakano Ogawa
- Department of Microbiology, Faculty of Pharmaceutical Sciences, Okayama University, Tsushima, Kita-ku, Okayama 700-8530, Japan; Department of Microbiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Tsushima, Kita-ku, Okayama 700-8530, Japan; Department of Microbiology and Biochemistry, Daiichi University of Pharmacy, Tamagawa-machi, Minami-ku, Fukuoka 815-8511, Japan.
| |
Collapse
|
11
|
Zamorano-Sánchez D, Alejandre-Sixtos JE, Arredondo-Hernández A, Martínez-Méndez R. OpaR Exerts a Dynamic Control over c-di-GMP Homeostasis and cpsA Expression in Vibrio parahaemolyticus through Its Regulation of ScrC and the Trigger Phosphodiesterase TpdA. Microbiol Spectr 2023; 11:e0087223. [PMID: 37199626 PMCID: PMC10269520 DOI: 10.1128/spectrum.00872-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Accepted: 05/04/2023] [Indexed: 05/19/2023] Open
Abstract
The second messenger cyclic dimeric GMP (c-di-GMP) plays a central role in controlling decision-making processes that are vitally important for the environmental survival of the human pathogen Vibrio parahaemolyticus. The mechanisms by which c-di-GMP levels and biofilm formation are dynamically controlled in V. parahaemolyticus are poorly understood. Here, we report the involvement of OpaR in controlling c-di-GMP metabolism and its effects on the expression of the trigger phosphodiesterase (PDE) TpdA and the biofilm-matrix related gene cpsA. Our results revealed that OpaR negatively modulates the expression of tpdA by maintaining a baseline level of c-di-GMP. The OpaR-regulated PDEs ScrC, ScrG, and VP0117 enable the upregulation of tpdA, to different degrees, in the absence of OpaR. We also found that TpdA plays the dominant role in c-di-GMP degradation under planktonic conditions compared to the other OpaR-regulated PDEs. In cells growing on solid medium, we observed that the role of the dominant c-di-GMP degrader alternates between ScrC and TpdA. We also report contrasting effects of the absence of OpaR on cpsA expression in cells growing on solid media compared to cells forming biofilms over glass. These results suggest that OpaR can act as a double-edged sword to control cpsA expression and perhaps biofilm development in response to poorly understood environmental factors. Finally, using an in-silico analysis, we indicate outlets of the OpaR regulatory module that can impact decision making during the motile-to-sessile transition in V. parahaemolyticus. IMPORTANCE The second messenger c-di-GMP is extensively used by bacterial cells to control crucial social adaptations such as biofilm formation. Here, we explore the role of the quorum-sensing regulator OpaR, from the human pathogen V. parahaemolyticus, on the dynamic control of c-di-GMP signaling and biofilm-matrix production. We found that OpaR is crucial to c-di-GMP homeostasis in cells growing on Lysogeny Broth agar and that the OpaR-regulated PDEs TpdA and ScrC alternate in the dominant role over time. Furthermore, OpaR plays contrasting roles in controlling the expression of the biofilm-related gene cpsA on different surfaces and growth conditions. This dual role has not been reported for orthologues of OpaR, such as HapR from Vibrio cholerae. It is important to investigate the origins and consequences of the differences in c-di-GMP signaling between closely and distantly related pathogens to better understand pathogenic bacterial behavior and its evolution.
Collapse
Affiliation(s)
- David Zamorano-Sánchez
- Programa de Microbiología Genómica, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, Mexico
| | - Jesús E. Alejandre-Sixtos
- Programa de Microbiología Genómica, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, Mexico
| | - Adilene Arredondo-Hernández
- Programa de Microbiología Genómica, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, Mexico
| | - Raquel Martínez-Méndez
- Programa de Microbiología Genómica, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, Mexico
| |
Collapse
|
12
|
Junkermeier EH, Hengge R. Local signaling enhances output specificity of bacterial c-di-GMP signaling networks. MICROLIFE 2023; 4:uqad026. [PMID: 37251514 PMCID: PMC10211494 DOI: 10.1093/femsml/uqad026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 05/08/2023] [Accepted: 05/10/2023] [Indexed: 05/31/2023]
Abstract
For many years the surprising multiplicity, signal input diversity, and output specificity of c-di-GMP signaling proteins has intrigued researchers studying bacterial second messengers. How can several signaling pathways act in parallel to produce specific outputs despite relying on the same diffusible second messenger maintained at a certain global cellular concentration? Such high specificity and flexibility arise from combining modes of local and global c-di-GMP signaling in complex signaling networks. Local c-di-GMP signaling can be experimentally shown by three criteria being met: (i) highly specific knockout phenotypes for particular c-di-GMP-related enzymes, (ii) actual cellular c-di-GMP levels that remain unchanged by such mutations and/or below the Kd's of the relevant c-di-GMP-binding effectors, and (iii) direct interactions between the signaling proteins involved. Here, we discuss the rationale behind these criteria and present well-studied examples of local c-di-GMP signaling in Escherichia coli and Pseudomonas. Relatively simple systems just colocalize a local source and/or a local sink for c-di-GMP, i.e. a diguanylate cyclase (DGC) and/or a specific phosphodiesterase (PDE), respectively, with a c-di-GMP-binding effector/target system. More complex systems also make use of regulatory protein interactions, e.g. when a "trigger PDE" responds to locally provided c-di-GMP, and thereby serves as a c-di-GMP-sensing effector that directly controls a target's activity, or when a c-di-GMP-binding effector recruits and directly activates its own "private" DGC. Finally, we provide an outlook into how cells can combine local and global signaling modes of c-di-GMP and possibly integrate those into other signaling nucleotides networks.
Collapse
Affiliation(s)
- Eike H Junkermeier
- Institut für Biologie/Mikrobiologie, Humboldt-Universität zu Berlin, Philippstr. 13 – Haus 22, 10115 Berlin, Germany
| | - Regine Hengge
- Corresponding author. Institut für Biologie/Mikrobiologie, Humboldt-Universität zu Berlin, Philippstr. 13 – Haus 22, 10115 Berlin, Germany. Tel: +49-30-2093-49686; Fax: +49-30-2093-49682; E-mail:
| |
Collapse
|
13
|
Hengge R, Pruteanu M, Stülke J, Tschowri N, Turgay K. Recent advances and perspectives in nucleotide second messenger signaling in bacteria. MICROLIFE 2023; 4:uqad015. [PMID: 37223732 PMCID: PMC10118264 DOI: 10.1093/femsml/uqad015] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Revised: 03/28/2023] [Accepted: 04/13/2023] [Indexed: 05/25/2023]
Abstract
Nucleotide second messengers act as intracellular 'secondary' signals that represent environmental or cellular cues, i.e. the 'primary' signals. As such, they are linking sensory input with regulatory output in all living cells. The amazing physiological versatility, the mechanistic diversity of second messenger synthesis, degradation, and action as well as the high level of integration of second messenger pathways and networks in prokaryotes has only recently become apparent. In these networks, specific second messengers play conserved general roles. Thus, (p)ppGpp coordinates growth and survival in response to nutrient availability and various stresses, while c-di-GMP is the nucleotide signaling molecule to orchestrate bacterial adhesion and multicellularity. c-di-AMP links osmotic balance and metabolism and that it does so even in Archaea may suggest a very early evolutionary origin of second messenger signaling. Many of the enzymes that make or break second messengers show complex sensory domain architectures, which allow multisignal integration. The multiplicity of c-di-GMP-related enzymes in many species has led to the discovery that bacterial cells are even able to use the same freely diffusible second messenger in local signaling pathways that can act in parallel without cross-talking. On the other hand, signaling pathways operating with different nucleotides can intersect in elaborate signaling networks. Apart from the small number of common signaling nucleotides that bacteria use for controlling their cellular "business," diverse nucleotides were recently found to play very specific roles in phage defense. Furthermore, these systems represent the phylogenetic ancestors of cyclic nucleotide-activated immune signaling in eukaryotes.
Collapse
Affiliation(s)
- Regine Hengge
- Corresponding author. Institut für Biologie/Mikrobiologie, Humboldt-Universität zu Berlin, Philippstr. 13 – Haus 22, 10115 Berlin, Germany. Tel: +49-30-2093-49686; Fax: +49-30-2093-49682; E-mail:
| | | | - Jörg Stülke
- Department of General Microbiology, Institute of Microbiology and Genetics, Georg-August-Universität Göttingen, 37077 Göttingen, Germany
| | - Natalia Tschowri
- Institute of Microbiology, Leibniz-Universität Hannover, 30419 Hannover, Germany
| | - Kürşad Turgay
- Institute of Microbiology, Leibniz-Universität Hannover, 30419 Hannover, Germany
- Max Planck Unit for the Science of Pathogens, 10115 Berlin, Germany
| |
Collapse
|
14
|
Vongkampang T, Sreenivas K, Grey C, van Niel EWJ. Immobilization techniques improve volumetric hydrogen productivity of Caldicellulosiruptor species in a modified continuous stirred tank reactor. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2023; 16:25. [PMID: 36793132 PMCID: PMC9933333 DOI: 10.1186/s13068-023-02273-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Accepted: 01/30/2023] [Indexed: 02/17/2023]
Abstract
BACKGROUND Co-cultures and cell immobilization have been used for retaining biomass in a bioreactor, with the aim to improve the volumetric hydrogen productivity (QH2). Caldicellulosiruptor kronotskyensis is a strong cellulolytic species that possesses tāpirin proteins for attaching on lignocellulosic materials. C. owensensis has its reputation as a biofilm former. It was investigated whether continuous co-cultures of these two species with different types of carriers can improve the QH2. RESULTS QH2 up to 30 ± 0.2 mmol L-1 h-1 was obtained during pure culture of C. kronotskyensis with combined acrylic fibres and chitosan. In addition, the yield of hydrogen was 2.95 ± 0.1 mol H2 mol-1 sugars at a dilution rate (D) of 0.3 h-1. However, the second-best QH2 26.4 ± 1.9 mmol L-1 h-1 and 25.4 ± 0.6 mmol L-1 h-1 were obtained with a co-culture of C. kronotskyensis and C. owensensis with acrylic fibres only and a pure culture of C. kronotskyensis with acrylic fibres, respectively. Interestingly, the population dynamics revealed that C. kronotskyensis was the dominant species in the biofilm fraction, whereas C. owensensis was the dominant species in the planktonic phase. The highest amount of c-di-GMP (260 ± 27.3 µM at a D of 0.2 h-1) were found with the co-culture of C. kronotskyensis and C. owensensis without a carrier. This could be due to Caldicellulosiruptor producing c-di-GMP as a second messenger for regulation of the biofilms under the high dilution rate (D) to prevent washout. CONCLUSIONS The cell immobilization strategy using a combination of carriers exhibited a promising approach to enhance the QH2. The QH2 obtained during the continuous culture of C. kronotskyensis with combined acrylic fibres and chitosan gave the highest QH2 among the pure culture and mixed cultures of Caldicellulosiruptor in the current study. Moreover, it was the highest QH2 among all cultures of Caldicellulosiruptor species studied so far.
Collapse
Affiliation(s)
- Thitiwut Vongkampang
- Department of Applied Microbiology, Lund University, 124, 221 00, Lund, Sweden. .,Biorefinery and Functional Food Research Unit, Department of Biotechnology, Faculty of Technology, Mahasarakham University, Kantharawichai, Mahasarakham, 44150, Thailand.
| | - Krishnan Sreenivas
- grid.4514.40000 0001 0930 2361Department of Applied Microbiology, Lund University, 124, 221 00 Lund, Sweden
| | - Carl Grey
- grid.4514.40000 0001 0930 2361Department of Biotechnology, Lund University, 124, 221 00 Lund, Sweden
| | - Ed W. J. van Niel
- grid.4514.40000 0001 0930 2361Department of Applied Microbiology, Lund University, 124, 221 00 Lund, Sweden
| |
Collapse
|
15
|
Escobar MR, Lepek VC, Basile LA. Influence of cyclic di-GMP metabolism to T3SS expression, biofilm formation and symbiosis efficiency in Mesorhizobium japonicum MAFF303099. FEMS Microbiol Lett 2023; 370:fnad087. [PMID: 37632199 DOI: 10.1093/femsle/fnad087] [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: 04/20/2023] [Revised: 07/26/2023] [Accepted: 08/22/2023] [Indexed: 08/27/2023] Open
Abstract
A link between the T3SS and inhibition of swimming motility by the transcriptional regulator TtsI in Mesorhizobium japonicum MAFF303099 has been previously reported. Here, we show that mutants in T3SS components display impaired biofilm formation capacity, indicating that a functional T3SS, or at least pili formation, is required for this process. As a first approach to the cdiG regulation network in this bacterium, we started a study of the second messenger cdiG by overexpressing or by deleting some genes encoding cdiG metabolizing enzymes. Overexpression of two putative PDEs as well as deletion of various DGCs led to reduced biofilm formation on glass tubes. Mutation of dgc9509 also affected negatively the nodulation and symbiosis efficiency on Lotus plants, which can be related to the observed reduction in adhesion to plant roots. Results from transcriptional nopX- and ttsI-promoter-lacZ fusions suggested that cdiG negatively regulates T3SS expression in M. japonicum MAFF303099.
Collapse
Affiliation(s)
- Mariel R Escobar
- Instituto de Investigaciones Biotecnológicas "Dr. Rodolfo Ugalde", Escuela de Bio y Nanotecnologías, Universidad Nacional de San Martín (IIBio-EByN-UNSAM), CONICET. Av. 25 de Mayo y Francia, San Martín, Buenos Aires, Argentina
| | - Viviana C Lepek
- Instituto de Investigaciones Biotecnológicas "Dr. Rodolfo Ugalde", Escuela de Bio y Nanotecnologías, Universidad Nacional de San Martín (IIBio-EByN-UNSAM), CONICET. Av. 25 de Mayo y Francia, San Martín, Buenos Aires, Argentina
| | - Laura A Basile
- Instituto de Investigaciones Biotecnológicas "Dr. Rodolfo Ugalde", Escuela de Bio y Nanotecnologías, Universidad Nacional de San Martín (IIBio-EByN-UNSAM), CONICET. Av. 25 de Mayo y Francia, San Martín, Buenos Aires, Argentina
| |
Collapse
|
16
|
Gong H, Jiang W, Yang Y, Zhang Y, Chen X, Li W, Yang P, Wang Z, Wang Q, Li Y. Cyclic di-GMP regulates bacterial colonization and further biocontrol efficacy of Bacillus velezensis against apple ring rot disease via its potential receptor YdaK. Front Microbiol 2022; 13:1034168. [PMID: 36590391 PMCID: PMC9800504 DOI: 10.3389/fmicb.2022.1034168] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 11/02/2022] [Indexed: 12/23/2022] Open
Abstract
Bacillus species are among the most investigated beneficial bacteria and widely used in agricultural systems as biological control agents. Its biocontrol efficacy is controlled by diverse regulators. Cyclic diguanylate (c-di-GMP) is a nearly universal second messenger in bacteria and modulates various important physiological processes, including motility, biofilm formation, antifungal antibiotic production and host colonization. However, the impact of c-di-GMP on biocontrol efficacy of beneficial bacteria is unknown. Bacillus velezensis PG12 is an effective biocontrol strain against apple ring rot disease caused by Botryosphaeria dothidea. In this study, the contribution of c-di-GMP to biocontrol efficacy of B. velezensis PG12 was investigated. Deletion of single gene encoding diguanylate cyclase or phosphodiesterase did not affect its biocontrol efficacy against apple ring rot. However, artificial modulation of c-di-GMP level in the cells leads to a significant change of biocontrol efficacy, suggesting that c-di-GMP positively regulates biocontrol efficacy of B. velezensis PG12 against apple ring rot disease. More evidences indicate that c-di-GMP does not affect the antagonistic activity of B. velezensis PG12 against B. dothidea in vitro and in vivo, but positively regulates biofilm formation of B. velezensis PG12 and its colonization on apple fruits. Importantly, deletion of ydaK could rescue the inhibition of biofilm formation, bacterial colonization and biocontrol efficacy caused by low c-di-GMP level, indicating that YdaK is the potential c-di-GMP receptor to regulate biofilm formation, colonization and effective biological control. However, YdaK did not affect the antagonistic activity of B. velezensis PG12 against B. dothidea. Based on these findings, we propose that c-di-GMP regulates biofilm formation, subsequently the bacterial colonization on apple fruits and thus biocontrol efficacy of B. velezensis through its receptor YdaK. This is the first report showing that c-di-GMP plays a role in biocontrol efficacy of beneficial bacteria.
Collapse
Affiliation(s)
- Huiling Gong
- Department of Plant Pathology, College of Plant Protection, China Agricultural University, Beijing, China
| | - Wenxiao Jiang
- Department of Plant Pathology, College of Plant Protection, China Agricultural University, Beijing, China
| | - Yang Yang
- Chongqing Key Laboratory of Plant Disease Biology, College of Plant Protection, Southwest University, Chongqing, China
| | - Yue Zhang
- Department of Plant Pathology, College of Plant Protection, China Agricultural University, Beijing, China
| | - Xufei Chen
- Department of Plant Pathology, College of Plant Protection, China Agricultural University, Beijing, China
| | - Wei Li
- Department of Plant Pathology, College of Plant Protection, China Agricultural University, Beijing, China
| | - Panlei Yang
- Department of Plant Pathology, College of Plant Protection, China Agricultural University, Beijing, China
| | - Zhenshuo Wang
- Department of Plant Pathology, College of Plant Protection, China Agricultural University, Beijing, China
| | - Qi Wang
- Department of Plant Pathology, College of Plant Protection, China Agricultural University, Beijing, China
| | - Yan Li
- Department of Plant Pathology, College of Plant Protection, China Agricultural University, Beijing, China,*Correspondence: Yan Li,
| |
Collapse
|
17
|
Yuan Y, Zhang F, Ai L, Huang Y, Peng R. Insight into the role of a novel c-di-GMP effector protein in Rhodococcus ruber. Biochem Biophys Res Commun 2022; 608:177-182. [DOI: 10.1016/j.bbrc.2022.03.131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 03/24/2022] [Indexed: 11/02/2022]
|
18
|
High Abundance of Transcription Regulators Compacts the Nucleoid in Escherichia coli. J Bacteriol 2022; 204:e0002622. [PMID: 35583339 DOI: 10.1128/jb.00026-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In enteric bacteria organization of the circular chromosomal DNA into a highly dynamic and toroidal-shaped nucleoid involves various factors, such as DNA supercoiling, nucleoid-associated proteins (NAPs), the structural maintenance of chromatin (SMC) complex, and macrodomain organizing proteins. Here, we show that ectopic expression of transcription regulators at high levels leads to nucleoid compaction. This serendipitous result was obtained by fluorescence microscopy upon ectopic expression of the transcription regulator and phosphodiesterase PdeL of Escherichia coli. Nucleoid compaction by PdeL depends on DNA-binding, but not on its enzymatic phosphodiesterase activity. Nucleoid compaction was also observed upon high-level ectopic expression of the transcription regulators LacI, RutR, RcsB, LeuO, and Cra, which range from single-target gene regulators to global regulators. In the case of LacI, its high-level expression in the presence of the gratuitous inducer IPTG (isopropyl-β-d-thiogalactopyranoside) also led to nucleoid compaction, indicating that compaction is caused by unspecific DNA-binding. In all cases nucleoid compaction correlated with misplacement of the FtsZ ring and loss of MukB foci, a subunit of the SMC complex. Thus, high levels of several transcription regulators cause nucleoid compaction with consequences for replication and cell division. IMPORTANCE The bacterial nucleoid is a highly organized and dynamic structure for simultaneous transcription, replication, and segregation of the bacterial genome. Compaction of the nucleoid and disturbance of DNA segregation and cell division by artificially high levels of transcription regulators, as described here, reveals that an excess of DNA-binding protein disturbs nucleoid structuring. The results suggest that ectopic expression levels of DNA-binding proteins for genetic studies of their function but also for their purification should be carefully controlled and adjusted.
Collapse
|
19
|
Wang X, He Y, Deng Y, Zuo Z, Li D, Chen F, Qu C, Miao J. A diguanylate cyclase regulates biofilm formation in Rhodococcus sp. NJ-530 from Antarctica. 3 Biotech 2022; 12:27. [PMID: 35036275 PMCID: PMC8710177 DOI: 10.1007/s13205-021-03093-z] [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: 08/26/2021] [Accepted: 12/11/2021] [Indexed: 01/03/2023] Open
Abstract
Biofilms represent a protective survival mode in which bacteria adapt themselves to the natural environment for survival purposes. Biofilm formation is regulated by 3,5-cyclic diguanylic acid (c-di-GMP), which is a universal second messenger molecule in bacteria. Diguanylate cyclase (DGC) catalyses c-di-GMP intracellular synthesis, which plays important roles in bacterial adaptation to the natural environment. In this study, the DGC gene was first cloned from Antarctic Rhodococcus sp. NJ-530. DGC contained 948 nucleotides and encoded 315 amino acids with a molecular weight of 34.6 KDa and an isoelectric point of 5.58. qRT-PCR demonstrated that the DGC expression level was significantly affected by lower salinity and temperature. Consistently, more biofilm formation occurred under the same stress. It has been shown that Rhodococcus sp. NJ-530 can adapt to the extreme environment in Antarctica, which is closely related to biofilm formation. These results provide an important reference for studying the adaptive mechanism of Antarctic microorganisms to this extreme environment. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1007/s13205-021-03093-z.
Collapse
Affiliation(s)
- Xixi Wang
- College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao, 266042 China
- Key Laboratory of Marine Eco-Environmental Science and Technology, First Institute of Oceanography, Ministry of Natural Resource, No. 6 of Xianxialing Road, Qingdao, 266061 China
| | - Yingying He
- Key Laboratory of Marine Eco-Environmental Science and Technology, First Institute of Oceanography, Ministry of Natural Resource, No. 6 of Xianxialing Road, Qingdao, 266061 China
| | - Yashan Deng
- College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao, 266042 China
- Key Laboratory of Marine Eco-Environmental Science and Technology, First Institute of Oceanography, Ministry of Natural Resource, No. 6 of Xianxialing Road, Qingdao, 266061 China
| | - Zhicong Zuo
- Key Laboratory of Marine Eco-Environmental Science and Technology, First Institute of Oceanography, Ministry of Natural Resource, No. 6 of Xianxialing Road, Qingdao, 266061 China
| | - Dan Li
- College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao, 266042 China
- Key Laboratory of Marine Eco-Environmental Science and Technology, First Institute of Oceanography, Ministry of Natural Resource, No. 6 of Xianxialing Road, Qingdao, 266061 China
| | - Fushan Chen
- College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao, 266042 China
| | - Changfeng Qu
- Key Laboratory of Marine Eco-Environmental Science and Technology, First Institute of Oceanography, Ministry of Natural Resource, No. 6 of Xianxialing Road, Qingdao, 266061 China
- Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237 China
| | - Jinlai Miao
- Key Laboratory of Marine Eco-Environmental Science and Technology, First Institute of Oceanography, Ministry of Natural Resource, No. 6 of Xianxialing Road, Qingdao, 266061 China
- Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237 China
| |
Collapse
|
20
|
A Novel Locally c-di-GMP-Controlled Exopolysaccharide Synthase Required for Bacteriophage N4 Infection of Escherichia coli. mBio 2021; 12:e0324921. [PMID: 34903052 PMCID: PMC8669469 DOI: 10.1128/mbio.03249-21] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
A major target of c-di-GMP signaling is the production of biofilm-associated extracellular polymeric substances (EPS), which in Escherichia coli K-12 include amyloid curli fibers, phosphoethanolamine-modified cellulose, and poly-N-acetylglucosamine. However, the characterized c-di-GMP-binding effector systems are largely outnumbered by the 12 diguanylate cyclases (DGCs) and 13 phosphodiesterases (PDEs), which synthetize and degrade c-di-GMP, respectively. E. coli possesses a single protein with a potentially c-di-GMP-binding MshEN domain, NfrB, which-together with the outer membrane protein NfrA-is known to serve as a receptor system for phage N4. Here, we show that NfrB not only binds c-di-GMP with high affinity but, as a novel c-di-GMP-controlled glycosyltransferase, synthesizes a secreted EPS, which can impede motility and is required as an initial receptor for phage N4 infection. In addition, a systematic screening of the 12 DGCs of E. coli K-12 revealed that specifically DgcJ is required for the infection with phage N4 and interacts directly with NfrB. This is in line with local signaling models, where specific DGCs and/or PDEs form protein complexes with particular c-di-GMP effector/target systems. Our findings thus provide further evidence that intracellular signaling pathways, which all use the same diffusible second messenger, can act in parallel in a highly specific manner. IMPORTANCE Key findings in model organisms led to the concept of "local" signaling, challenging the dogma of a gradually increasing global intracellular c-di-GMP concentration driving the motile-sessile transition in bacteria. In our current model, bacteria dynamically combine both global and local signaling modes, in which specific DGCs and/or PDEs team up with effector/target systems in multiprotein complexes. The present study highlights a novel example of how specificity in c-di-GMP signaling can be achieved by showing NfrB as a novel c-di-GMP binding effector in E. coli, which is controlled in a local manner specifically by DgcJ. We further show that NfrB (which was initially found as a part of a receptor system for phage N4) is involved in the production of a novel exopolysaccharide. Finally, our data shine new light on host interaction of phage N4, which uses this exopolysaccharide as an initial receptor for adsorption.
Collapse
|
21
|
Serra DO, Hengge R. Bacterial Multicellularity: The Biology of Escherichia coli Building Large-Scale Biofilm Communities. Annu Rev Microbiol 2021; 75:269-290. [PMID: 34343018 DOI: 10.1146/annurev-micro-031921-055801] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Biofilms are a widespread multicellular form of bacterial life. The spatial structure and emergent properties of these communities depend on a polymeric extracellular matrix architecture that is orders of magnitude larger than the cells that build it. Using as a model the wrinkly macrocolony biofilms of Escherichia coli, which contain amyloid curli fibers and phosphoethanolamine (pEtN)-modified cellulose as matrix components, we summarize here the structure, building, and function of this large-scale matrix architecture. Based on different sigma and other transcription factors as well as second messengers, the underlying regulatory network reflects the fundamental trade-off between growth and survival. It controls matrix production spatially in response to long-range chemical gradients, but it also generates distinct patterns of short-range matrix heterogeneity that are crucial for tissue-like elasticity and macroscopic morphogenesis. Overall, these biofilms confer protection and a potential for homeostasis, thereby reducing maintenance energy, which makes multicellularity an emergent property of life itself. Expected final online publication date for the Annual Review of Microbiology, Volume 75 is October 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
Collapse
Affiliation(s)
- Diego O Serra
- Instituto de Biología Molecular y Celular de Rosario (IBR), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Rosario (UNR), 2000 Rosario, Argentina
| | - Regine Hengge
- Institut für Biologie/Mikrobiologie, Humboldt-Universität zu Berlin, 10115 Berlin, Germany;
| |
Collapse
|
22
|
Banerjee P, Sahoo PK, Sheenu, Adhikary A, Ruhal R, Jain D. Molecular and structural facets of c-di-GMP signalling associated with biofilm formation in Pseudomonas aeruginosa. Mol Aspects Med 2021; 81:101001. [PMID: 34311995 DOI: 10.1016/j.mam.2021.101001] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 05/09/2021] [Accepted: 07/16/2021] [Indexed: 12/29/2022]
Abstract
Pseudomonas aeruginosa is an opportunistic human pathogen and is the primary cause of nosocomial infections. Biofilm formation by this organism results in chronic and hard to eradicate infections. The intracellular signalling molecule bis-(3'-5')-cyclic dimeric guanosine monophosphate (c-di-GMP) is a secondary messenger in bacterial cells crucial for motile to sessile transition. The signalling pathway components encompass two classes of enzymes with antagonistic activities, the diguanylate cyclases (DGCs) and phosphodiesterases (PDEs) that regulate the cellular levels of c-di-GMP at distinct stages of biofilm initiation, maturation and dispersion. This review summarizes the structural analysis and functional studies of the DGCs and PDEs involved in biofilm regulation in P. aeruginosa. In addition, we also describe the effector proteins that sense the perturbations in c-di-GMP levels to elicit a functional output. Finally, we discuss possible mechanisms that allow the dynamic levels of c-di-GMP to regulate cognate cellular response. Uncovering the details of the regulation of the c-di-GMP signalling pathway is vital for understanding the behaviour of the pathogen and characterization of novel targets for anti-biofilm interventions.
Collapse
Affiliation(s)
- Priyajit Banerjee
- Transcription Regulation Lab, Regional Centre for Biotechnology, NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad, 121001, India; Kalinga Institute of Industrial Technology, Bhubaneswar, Odisha, 751024, India
| | - Pankaj Kumar Sahoo
- Transcription Regulation Lab, Regional Centre for Biotechnology, NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad, 121001, India
| | - Sheenu
- Transcription Regulation Lab, Regional Centre for Biotechnology, NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad, 121001, India
| | - Anirban Adhikary
- Transcription Regulation Lab, Regional Centre for Biotechnology, NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad, 121001, India
| | - Rohit Ruhal
- Transcription Regulation Lab, Regional Centre for Biotechnology, NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad, 121001, India
| | - Deepti Jain
- Transcription Regulation Lab, Regional Centre for Biotechnology, NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad, 121001, India.
| |
Collapse
|
23
|
Fu Y, Yu Z, Zhu L, Li Z, Yin W, Shang X, Chou SH, Tan Q, He J. The Multiple Regulatory Relationship Between RNA-Chaperone Hfq and the Second Messenger c-di-GMP. Front Microbiol 2021; 12:689619. [PMID: 34335515 PMCID: PMC8323549 DOI: 10.3389/fmicb.2021.689619] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 06/18/2021] [Indexed: 11/25/2022] Open
Abstract
RNA chaperone protein Hfq is an important post-transcriptional regulator in bacteria, while c-di-GMP is a second messenger signaling molecule widely distributed in bacteria. Both factors have been found to play key roles in post-transcriptional regulation and signal transduction pathways, respectively. Intriguingly, the two factors show some common aspects in the regulation of certain physiological functions such as bacterial motility, biofilm formation, pathogenicity and so on. Therefore, there may be regulatory relationship between Hfq and c-di-GMP. For example, Hfq can directly regulate the activity of c-di-GMP metabolic enzymes or alter the c-di-GMP level through other systems, while c-di-GMP can indirectly enhance or inhibit the hfq gene expression through intermediate factors. In this article, after briefly introducing the Hfq and c-di-GMP regulatory systems, we will focus on the direct and indirect regulation reported between Hfq and c-di-GMP, aiming to compare and link the two regulatory systems to further study the complicated physiological and metabolic systems of bacteria, and to lay a solid foundation for drawing a more complete global regulatory network.
Collapse
Affiliation(s)
- Yang Fu
- National Engineering Research Center of Edible Fungi, Institute of Edible Fungi, Shanghai Academy of Agricultural Sciences, Shanghai, China.,State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Zhaoqing Yu
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Li Zhu
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Zhou Li
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Wen Yin
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Xiaodong Shang
- National Engineering Research Center of Edible Fungi, Institute of Edible Fungi, Shanghai Academy of Agricultural Sciences, Shanghai, China
| | - Shan-Ho Chou
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Qi Tan
- National Engineering Research Center of Edible Fungi, Institute of Edible Fungi, Shanghai Academy of Agricultural Sciences, Shanghai, China
| | - Jin He
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| |
Collapse
|
24
|
Li H, Ma X, Tang Y, Wang D, Zhang Z, Liu Z. Network-based analysis of virulence factors for uncovering Aeromonas veronii pathogenesis. BMC Microbiol 2021; 21:188. [PMID: 34162325 PMCID: PMC8223281 DOI: 10.1186/s12866-021-02261-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Accepted: 06/15/2021] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Aeromonas veronii is a bacterial pathogen in aquaculture, which produces virulence factors to enable it colonize and evade host immune defense. Given that experimental verification of virulence factors is time-consuming and laborious, few virulence factors have been characterized. Moreover, most studies have only focused on single virulence factors, resulting in biased interpretation of the pathogenesis of A. veronii. RESULTS In this study, a PPI network at genome-wide scale for A. veronii was first constructed followed by prediction and mapping of virulence factors on the network. When topological characteristics were analyzed, the virulence factors had higher degree and betweenness centrality than other proteins in the network. In particular, the virulence factors tended to interact with each other and were enriched in two network modules. One of the modules mainly consisted of histidine kinases, response regulators, diguanylate cyclases and phosphodiesterases, which play important roles in two-component regulatory systems and the synthesis and degradation of cyclic-diGMP. Construction of the interspecies PPI network between A. veronii and its host Oreochromis niloticus revealed that the virulence factors interacted with homologous proteins in the host. Finally, the structures and interacting sites of the virulence factors during interaction with host proteins were predicted. CONCLUSIONS The findings here indicate that the virulence factors probably regulate the virulence of A. veronii by involving in signal transduction pathway and manipulate host biological processes by mimicking and binding competitively to host proteins. Our results give more insight into the pathogenesis of A. veronii and provides important information for designing targeted antibacterial drugs.
Collapse
Affiliation(s)
- Hong Li
- School of Life Sciences, Hainan University, Haikou, China
| | - Xiang Ma
- School of Life Sciences, Hainan University, Haikou, China
| | - Yanqiong Tang
- School of Life Sciences, Hainan University, Haikou, China
| | - Dan Wang
- Key Laboratory for Sustainable Utilization of Tropical Bioresource, College of Tropical Crops, Hainan University, Haikou, China
| | - Ziding Zhang
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Zhu Liu
- School of Life Sciences, Hainan University, Haikou, China.
| |
Collapse
|
25
|
A Trigger Phosphodiesterase Modulates the Global c-di-GMP Pool, Motility, and Biofilm Formation in Vibrio parahaemolyticus. J Bacteriol 2021; 203:e0004621. [PMID: 33846117 DOI: 10.1128/jb.00046-21] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Vibrio parahaemolyticus cells transit from free-swimming to surface adapted lifestyles, such as swarming colonies and three-dimensional biofilms. These transitions are regulated by sensory modules and regulatory networks that involve the second messenger cyclic diguanylate monophosphate (c-di-GMP). In this work, we show that a previously uncharacterized c-di-GMP phosphodiesterase (VP1881) from V. parahaemolyticus plays an important role in modulating the c-di-GMP pool. We found that the product of VP1881 promotes its own expression when the levels of c-di-GMP are low or when the phosphodiesterase (PDE) is catalytically inactive. This behavior has been observed in a class of c-di-GMP receptors called trigger phosphodiesterases, and hence we named the product of VP1881 TpdA, for trigger phosphodiesterase A. The absence of tpdA showed a negative effect on swimming motility while, its overexpression from an isopropyl-β-d-thiogalactopyranoside (IPTG)-inducible promoter showed a positive effect on both swimming and swarming motility and a negative effect on biofilm formation. Changes in TpdA abundance altered the expression of representative polar and lateral flagellar genes, as well as that of the biofilm-related gene cpsA. Our results also revealed that autoactivation of the native PtpdA promoter is sufficient to alter c-di-GMP signaling responses such as swarming and biofilm formation in V. parahaemolyticus, an observation that could have important implications in the dynamics of these social behaviors. IMPORTANCE c-di-GMP trigger phosphodiesterases (PDEs) could play a key role in controlling the heterogeneity of biofilm matrix composition, a property that endows characteristics that are potentially relevant for sustaining integrity and functionality of biofilms in a variety of natural environments. Trigger PDEs are not always easy to identify based on their sequence, and hence not many examples of these type of signaling proteins have been reported in the literature. Here, we report on the identification of a novel trigger PDE in V. parahaemolyticus and provide evidence suggesting that its autoactivation could play an important role in the progression of swarming motility and biofilm formation, multicellular behaviors that are important for the survival and dissemination of this environmental pathogen.
Collapse
|
26
|
De Smet J, Wagemans J, Hendrix H, Staes I, Visnapuu A, Horemans B, Aertsen A, Lavigne R. Bacteriophage-mediated interference of the c-di-GMP signalling pathway in Pseudomonas aeruginosa. Microb Biotechnol 2021; 14:967-978. [PMID: 33314648 PMCID: PMC8085984 DOI: 10.1111/1751-7915.13728] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 10/19/2020] [Accepted: 11/22/2020] [Indexed: 01/10/2023] Open
Abstract
C-di-GMP is a key signalling molecule which impacts bacterial motility and biofilm formation and is formed by the condensation of two GTP molecules by a diguanylate cyclase. We here describe the identification and characterization of a family of bacteriophage-encoded peptides that directly impact c-di-GMP signalling in Pseudomonas aeruginosa. These phage proteins target Pseudomonas diguanylate cyclase YfiN by direct protein interaction (termed YIPs, YfiN Interacting Peptides). YIPs induce an increase of c-di-GMP production in the host cell, resulting in a decrease in motility and an increase in biofilm mass in P. aeruginosa. A dynamic analysis of the biofilm morphology indicates a denser biofilm structure after induction of the phage protein. This intracellular signalling interference strategy by a lytic phage constitutes an unexplored phage-based mechanism of metabolic regulation and could potentially serve as inspiration for the development of molecules that interfere with biofilm formation in P. aeruginosa and other pathogens.
Collapse
Affiliation(s)
- Jeroen De Smet
- Laboratory of Gene TechnologyDepartment of BiosystemsKU LeuvenHeverlee3001Belgium
- Present address:
Lab4FoodDepartment of Microbial and Molecular Systems (M2S)KU Leuven Campus GeelGeel2440Belgium
| | - Jeroen Wagemans
- Laboratory of Gene TechnologyDepartment of BiosystemsKU LeuvenHeverlee3001Belgium
| | - Hanne Hendrix
- Laboratory of Gene TechnologyDepartment of BiosystemsKU LeuvenHeverlee3001Belgium
| | - Ines Staes
- Laboratory of Food MicrobiologyDepartment of Microbial and Molecular SystemsKU LeuvenHeverlee3001Belgium
| | - Annegrete Visnapuu
- Laboratory of Gene TechnologyDepartment of BiosystemsKU LeuvenHeverlee3001Belgium
| | - Benjamin Horemans
- Department of Earth and Environmental SciencesKU LeuvenHeverlee3001Belgium
| | - Abram Aertsen
- Laboratory of Food MicrobiologyDepartment of Microbial and Molecular SystemsKU LeuvenHeverlee3001Belgium
| | - Rob Lavigne
- Laboratory of Gene TechnologyDepartment of BiosystemsKU LeuvenHeverlee3001Belgium
| |
Collapse
|
27
|
Hengge R. High-Specificity Local and Global c-di-GMP Signaling. Trends Microbiol 2021; 29:993-1003. [PMID: 33640237 DOI: 10.1016/j.tim.2021.02.003] [Citation(s) in RCA: 58] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 01/31/2021] [Accepted: 02/01/2021] [Indexed: 11/26/2022]
Abstract
The striking multiplicity, signal input diversity, and output specificity of c-di-GMP signaling proteins in many bacteria has brought second messenger signaling back onto the agenda of contemporary microbiology. How can several signaling pathways act in parallel in a specific manner if all of them use the same diffusible second messenger present at a certain global cellular concentration? Recent research has now shown that bacteria achieve this by flexibly combining modes of local and global c-di-GMP signaling in complex signaling networks. Three criteria have to be met to define local c-di-GMP signaling: specific knockout phenotypes, direct interactions between proteins involved, and actual cellular c-di-GMP levels remaining below the Kd of effectors. Adaptive changes in signaling network architecture can further enhance signaling flexibility.
Collapse
Affiliation(s)
- Regine Hengge
- Institut für Biologie/Mikrobiologie, Humboldt-Universität zu Berlin, 10115 Berlin, Germany.
| |
Collapse
|
28
|
Quorum Sensing Signaling Molecules Positively Regulate c-di-GMP Effector PelD Encoding Gene and PEL Exopolysaccharide Biosynthesis in Extremophile Bacterium Acidithiobacillus thiooxidans. Genes (Basel) 2021; 12:genes12010069. [PMID: 33430222 PMCID: PMC7825692 DOI: 10.3390/genes12010069] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 12/09/2020] [Accepted: 12/11/2020] [Indexed: 01/20/2023] Open
Abstract
Acidithiobacillus species are fundamental players in biofilm formation by acidophile bioleaching communities. It has been previously reported that Acidithiobacillus ferrooxidans possesses a functional quorum sensing mediated by acyl-homoserine lactones (AHL), involved in biofilm formation, and AHLs naturally produced by Acidithiobacillus species also induce biofilm formation in Acidithiobacillus thiooxidans. A c-di-GMP pathway has been characterized in Acidithiobacillus species but it has been pointed out that the c-di-GMP effector PelD and pel-like operon are only present in the sulfur oxidizers such as A. thiooxidans. PEL exopolysaccharide has been recently involved in biofilm formation in this Acidithiobacillus species. Here, by comparing wild type and ΔpelD strains through mechanical analysis of biofilm-cells detachment, fluorescence microscopy and qPCR experiments, the structural role of PEL exopolysaccharide and the molecular network involved for its biosynthesis by A. thiooxidans were tackled. Besides, the effect of AHLs on PEL exopolysaccharide production was assessed. Mechanical resistance experiments indicated that the loss of PEL exopolysaccharide produces fragile A. thiooxidans biofilms. qRT-PCR analysis established that AHLs induce the transcription of pelA and pelD genes while epifluorescence microscopy studies revealed that PEL exopolysaccharide was required for the development of AHL-induced biofilms. Altogether these results reveal for the first time that AHLs positively regulate pel genes and participate in the molecular network for PEL exopolysaccharide biosynthesis by A. thiooxidans.
Collapse
|
29
|
Yilmaz C, Rangarajan AA, Schnetz K. The transcription regulator and c-di-GMP phosphodiesterase PdeL represses motility in Escherichia coli. J Bacteriol 2020; 203:JB.00427-20. [PMID: 33318048 PMCID: PMC8095459 DOI: 10.1128/jb.00427-20] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 12/09/2020] [Indexed: 12/16/2022] Open
Abstract
PdeL is a transcription regulator and catalytically active c-di-GMP phosphodiesterases (PDE) in Escherichia coli PdeL has been shown to be a transcription autoregulator, while no other target genes have been identified so far. Here, we show that PdeL represses transcription of the flagella class II operon, fliFGHIJK, and activates sslE encoding an extracellular anchored metalloprotease, among additional loci. DNA-binding studies and expression analyses using plasmidic reporters suggest that regulation of the fliF and sslE promoters by PdeL is direct. Transcription repression of the fliFGHIJK operon, encoding protein required for assembly of the flagellar basal body, results in inhibition of motility on soft agar plates and reduction of flagella assembly, as shown by fluorescence staining of the flagella hook protein FlgE. PdeL-mediated repression of motility is independent of its phosphodiesterase activity. Thus, in motility control the transcription regulator function of PdeL reducing the number of assembled flagella is apparently epistatic to its phosphodiesterase function, which can indirectly promote the activity of the flagellar motor by lowering the c-di-GMP concentration.Bacteria adopt different lifestyles depending on their environment and physiological condition. In Escherichia coli and other enteric bacteria the transition between the motile and the sessile state is controlled at multiple levels from the regulation of gene expression to the modulation of various processes by the second messenger c-di-GMP as signaling molecule. The significance of our research is in identifying PdeL, a protein of dual function that hydrolyzes c-di-GMP and that regulates transcription of genes, as a repressor of Flagella gene expression and an inhibitor of motility, which adds an additional regulatory switch to the control of motility.
Collapse
Affiliation(s)
- Cihan Yilmaz
- Institute for Genetics, University of Cologne, Zülpicher Str. 47a, 50674 Cologne, Germany
| | | | - Karin Schnetz
- Institute for Genetics, University of Cologne, Zülpicher Str. 47a, 50674 Cologne, Germany
| |
Collapse
|
30
|
Shahbaz MU, Qian S, Yun F, Zhang J, Yu C, Tian F, Yang F, Chen H. Identification of the Regulatory Components Mediated by the Cyclic di-GMP Receptor Filp and Its Interactor PilZX3 and Functioning in Virulence of Xanthomonas oryzae pv. oryzae. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2020; 33:1196-1208. [PMID: 32720873 DOI: 10.1094/mpmi-04-20-0088-r] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The degenerate GGDEF/EAL domain protein Filp was previously shown to function as a cyclic di-GMP (c-di-GMP) signal receptor through its specific interaction with an atypical PilZ domain protein PilZX3 (formerly PXO_02715) and that this interaction is involved in regulating virulence in Xanthomonas oryzae pv. oryzae. As a step toward understanding the regulatory role of Filp/PilZX3-mediated c-di-GMP signaling in the virulence of X. oryzae pv. oryzae, differentially expressed proteins (DEPs) downstream of Filp/PilZX3 were identified by isobaric tagging for relative and absolute quantitation (iTRAQ). A total of 2,346 proteins were identified, of which 157 displayed significant differential expression in different strains. Western blot and quantitative reverse transcription-PCR analyses showed that the expression of HrrP (histidine kinase-response regulator hybrid protein), PhrP (PhoPQ-regulated protein), ProP (prophage Lp2 protein 6) were increased in the ∆filp, ∆pilZX3, and ∆filp∆pilZX3 mutant strains, while expression of CheW1 (chemotaxis protein CheW1), EdpX2 (the second EAL domain protein identified in X. oryzae pv. oryzae), HGdpX2 (the second HD-GYP domain protein identified in X. oryzae pv. oryzae) was decreased in all mutant strains compared with that in the wild type, which was consistent with the iTRAQ data. Deletion of the hrrP and proP genes resulted in significant increases in virulence, whereas deletion of the cheW1, hGdpX2, or tdrX2 genes resulted in decreased virulence. Enzyme assays indicated that EdpX2 and HGdpX2 were active phosphodiesterases (PDEs). This study provides a proteomic description of putative regulatory pathway of Filp and PilZX3 and characterized novel factors that contributed to the virulence of X. oryzae pv. oryzae regulated by c-di-GMP signaling.
Collapse
Affiliation(s)
- Muhammad Umar Shahbaz
- State Key Laboratory for Biology Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
- Plant Pathology Section, Plant Pathology Research Institute, AARI, Faisalabad 38850, Pakistan
| | - Shanshan Qian
- State Key Laboratory for Biology Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Fei Yun
- National Tobacco Cultivation and Physiology and Biochemistry Research Centre/Key Laboratory for Tobacco Cultivation of Tobacco Industry, Henan Agricultural University, Zhengzhou 450002, China
| | - Jie Zhang
- State Key Laboratory for Biology Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Chao Yu
- State Key Laboratory for Biology Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Fang Tian
- State Key Laboratory for Biology Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Fenghuan Yang
- State Key Laboratory for Biology Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Huamin Chen
- State Key Laboratory for Biology Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| |
Collapse
|
31
|
Khan F, Tabassum N, Pham DTN, Oloketuyi SF, Kim YM. Molecules involved in motility regulation in Escherichia coli cells: a review. BIOFOULING 2020; 36:889-908. [PMID: 33028083 DOI: 10.1080/08927014.2020.1826939] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 09/14/2020] [Accepted: 09/15/2020] [Indexed: 06/11/2023]
Abstract
The initial colonization of the host organism by commensal, probiotic, and pathogenic Escherichia coli strains is an important step in the development of infections and biofilms. Sensing and colonization of host cell surfaces are governed by flagellar and fimbriae/pili appendages, respectively. Biofilm formation confers great advantages on pathogenic E. coli cells such as protection against the host immune system, antimicrobial agents, and several environmental stress factors. The transition from planktonic to sessile physiological states involves several signaling cascades and factors responsible for the regulation of flagellar motility in E. coli cells. These regulatory factors have thus become important targets to control pathogenicity. Hence, attenuation of flagellar motility is considered a potential therapy against pathogenic E. coli. The present review describes signaling pathways and proteins involved in direct or indirect regulation of flagellar motility. Furthermore, application strategies for antimotility natural or synthetic compounds are discussed also.
Collapse
Affiliation(s)
- Fazlurrahman Khan
- Institute of Food Science, Pukyong National University, Busan, Republic of Korea
| | - Nazia Tabassum
- Industrial Convergence Bionix Engineering, Pukyong National University, Busan, Republic of Korea
| | - Dung Thuy Nguyen Pham
- Department of Food Science and Technology, Pukyong National University, Busan, Republic of Korea
| | | | - Young-Mog Kim
- Institute of Food Science, Pukyong National University, Busan, Republic of Korea
- Department of Food Science and Technology, Pukyong National University, Busan, Republic of Korea
| |
Collapse
|
32
|
Richter AM, Possling A, Malysheva N, Yousef KP, Herbst S, von Kleist M, Hengge R. Local c-di-GMP Signaling in the Control of Synthesis of the E. coli Biofilm Exopolysaccharide pEtN-Cellulose. J Mol Biol 2020; 432:4576-4595. [PMID: 32534064 PMCID: PMC7397504 DOI: 10.1016/j.jmb.2020.06.006] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 05/20/2020] [Accepted: 06/08/2020] [Indexed: 12/17/2022]
Abstract
In many bacteria, the biofilm-promoting second messenger c-di-GMP is produced and degraded by multiple diguanylate cyclases (DGC) and phosphodiesterases (PDE), respectively. High target specificity of some of these enzymes has led to theoretical concepts of "local" c-di-GMP signaling. In Escherichia coli K-12, which has 12 DGCs and 13 PDEs, a single DGC, DgcC, is specifically required for the biosynthesis of the biofilm exopolysaccharide pEtN-cellulose without affecting the cellular c-di-GMP pool, but the mechanistic basis of this target specificity has remained obscure. DGC activity of membrane-associated DgcC, which is demonstrated in vitro in nanodiscs, is shown to be necessary and sufficient to specifically activate cellulose biosynthesis in vivo. DgcC and a particular PDE, PdeK (encoded right next to the cellulose operon), directly interact with cellulose synthase subunit BcsB and with each other, thus establishing physical proximity between cellulose synthase and a local source and sink of c-di-GMP. This arrangement provides a localized, yet open source of c-di-GMP right next to cellulose synthase subunit BcsA, which needs allosteric activation by c-di-GMP. Through mathematical modeling and simulation, we demonstrate that BcsA binding from the low cytosolic c-di-GMP pool in E. coli is negligible, whereas a single c-di-GMP molecule that is produced and released in direct proximity to cellulose synthase increases the probability of c-di-GMP binding to BcsA several hundred-fold. This local c-di-GMP signaling could provide a blueprint for target-specific second messenger signaling also in other bacteria where multiple second messenger producing and degrading enzymes exist.
Collapse
Affiliation(s)
- Anja M Richter
- Institute of Biology/Microbiology, Humboldt-Universität zu Berlin, 10115 Berlin, Germany; Department of Materials and the Environment, Bundesanstalt für Materialforschung und -Prüfung, 12205 Berlin, Germany
| | - Alexandra Possling
- Institute of Biology/Microbiology, Humboldt-Universität zu Berlin, 10115 Berlin, Germany
| | - Nadezhda Malysheva
- Department of Mathematics and Computer Science, Freie Universität Berlin, 14195 Berlin, Germany; MF1 Bioinformatics, Robert-Koch-Institut, 13353 Berlin, Germany
| | - Kaveh P Yousef
- Department of Mathematics and Computer Science, Freie Universität Berlin, 14195 Berlin, Germany
| | - Susanne Herbst
- Institute of Biology/Microbiology, Humboldt-Universität zu Berlin, 10115 Berlin, Germany
| | - Max von Kleist
- Department of Mathematics and Computer Science, Freie Universität Berlin, 14195 Berlin, Germany; MF1 Bioinformatics, Robert-Koch-Institut, 13353 Berlin, Germany
| | - Regine Hengge
- Institute of Biology/Microbiology, Humboldt-Universität zu Berlin, 10115 Berlin, Germany.
| |
Collapse
|
33
|
Petchiappan A, Naik SY, Chatterji D. Tracking the homeostasis of second messenger cyclic-di-GMP in bacteria. Biophys Rev 2020; 12:719-730. [PMID: 32060735 PMCID: PMC7311556 DOI: 10.1007/s12551-020-00636-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 02/05/2020] [Indexed: 01/09/2023] Open
Abstract
Cyclic-di-GMP (c-di-GMP) is an important second messenger in bacteria which regulates the bacterial transition from motile to sessile phase and also plays a major role in processes such as cell division, exopolysaccharide synthesis, and biofilm formation. Due to its crucial role in dictating the bacterial phenotype, the synthesis and hydrolysis of c-di-GMP is tightly regulated via multiple mechanisms. Perturbing the c-di-GMP homeostasis affects bacterial growth and survival, so it is necessary to understand the underlying mechanisms related to c-di-GMP metabolism. Most techniques used for estimating the c-di-GMP concentration lack single-cell resolution and do not provide information about any heterogeneous distribution of c-di-GMP inside cells. In this review, we briefly discuss how the activity of c-di-GMP metabolising enzymes, particularly bifunctional proteins, is modulated to maintain c-di-GMP homeostasis. We further highlight how fluorescence-based methods aid in understanding the spatiotemporal regulation of c-di-GMP signalling. Finally, we discuss the blind spots in our understanding of second messenger signalling and outline how they can be addressed in the future.
Collapse
Affiliation(s)
| | - Sujay Y Naik
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India
| | - Dipankar Chatterji
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India
| |
Collapse
|
34
|
Valentini M, Filloux A. Multiple Roles of c-di-GMP Signaling in Bacterial Pathogenesis. Annu Rev Microbiol 2020; 73:387-406. [PMID: 31500536 DOI: 10.1146/annurev-micro-020518-115555] [Citation(s) in RCA: 89] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The intracellular signaling molecule cyclic di-GMP (c-di-GMP) regulates the lifestyle of bacteria and controls many key functions and mechanisms. In the case of bacterial pathogens, a wide variety of virulence lifestyle factors have been shown to be regulated by c-di-GMP. Evidence of the importance of this molecule for bacterial pathogenesis has become so great that new antimicrobial agents are tested for their capacity of targeting c-di-GMP signaling. This review summarizes the current knowledge on this topic and reveals its application for the development of new antivirulence intervention strategies.
Collapse
Affiliation(s)
- Martina Valentini
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, CH-1211 Geneva 4, Switzerland;
| | - Alain Filloux
- MRC Centre for Molecular Microbiology and Infection, Department of Life Sciences, Imperial College London, SW7 2AZ London, United Kingdom;
| |
Collapse
|
35
|
Wallner T, Pedroza L, Voigt K, Kaever V, Wilde A. The cyanobacterial phytochrome 2 regulates the expression of motility-related genes through the second messenger cyclic di-GMP. Photochem Photobiol Sci 2020; 19:631-643. [PMID: 32255440 DOI: 10.1039/c9pp00489k] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The cyanobacterial phytochrome Cph2 is a light-dependent diguanylate cyclase of the cyanobacterium Synechocystis 6803. Under blue light, Cph2-dependent increase in the cellular c-di-GMP concentration leads to inhibition of surface motility and enhanced flocculation of cells in liquid culture. However, the targets of second messenger signalling in this cyanobacterium and its mechanism of action remained unclear. Here, we determined the cellular concentrations of cAMP and c-di-GMP in wild-type and Δcph2 cells after exposure to blue and green light. Inactivation of cph2 completely abolished the blue-light dependent increase in c-di-GMP content. Therefore, a microarray analysis with blue-light grown wild-type and Δcph2 mutant cells was used to identify c-di-GMP dependent alterations in transcript accumulation. The increase in the c-di-GMP content alters expression of genes encoding putative cell appendages, minor pilins and components of chemotaxis systems. The mRNA encoding the minor pilins pilA5-pilA6 was negatively affected by high c-di-GMP content under blue light, whereas the minor pilin encoding operon pilA9-slr2019 accumulates under these conditions, suggesting opposing functions of the respective gene sets. Artificial overproduction of c-di-GMP leads to similar changes in minor pilin gene expression and supports previous findings that c-di-GMP is important for flocculation via the function of minor pilins. Mutational and gene expression analysis further suggest that SyCRP2, a CRP-like transcription factor, is involved in regulation of minor pilin and putative chaperone usher pili gene expression.
Collapse
Affiliation(s)
- Thomas Wallner
- Molecular Genetics of Prokaryotes, Institute of Biology III, University of Freiburg, Freiburg, Germany.
| | - Laura Pedroza
- Molecular Genetics of Prokaryotes, Institute of Biology III, University of Freiburg, Freiburg, Germany
| | - Karsten Voigt
- Molecular Genetics of Prokaryotes, Institute of Biology III, University of Freiburg, Freiburg, Germany
| | - Volkhard Kaever
- Research Core Unit Metabolomics, Hannover Medical School, Hannover, Germany
| | - Annegret Wilde
- Molecular Genetics of Prokaryotes, Institute of Biology III, University of Freiburg, Freiburg, Germany
| |
Collapse
|
36
|
Hengge R. Linking bacterial growth, survival, and multicellularity - small signaling molecules as triggers and drivers. Curr Opin Microbiol 2020; 55:57-66. [PMID: 32244175 DOI: 10.1016/j.mib.2020.02.007] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 02/07/2020] [Accepted: 02/14/2020] [Indexed: 02/05/2023]
Abstract
An overarching theme of cellular regulation in bacteria arises from the trade-off between growth and stress resilience. In addition, the formation of biofilms contributes to stress survival, since these dense multicellular aggregates, in which cells are embedded in an extracellular matrix of self-produced polymers, represent a self-constructed protective and homeostatic 'niche'. As shown here for the model bacterium Escherichia coli, the inverse coordination of bacterial growth with survival and the transition to multicellularity is achieved by a highly integrated regulatory network with several sigma subunits of RNA polymerase and a small number of transcriptional hubs as central players. By conveying information about the actual (micro)environments, nucleotide second messengers such as cAMP, (p)ppGpp, and in particular c-di-GMP are the key triggers and drivers that promote either growth or stress resistance and organized multicellularity in a world of limited resources.
Collapse
Affiliation(s)
- Regine Hengge
- Institut für Biologie/Mikrobiologie, Humboldt-Universität zu Berlin, 10115 Berlin, Germany.
| |
Collapse
|
37
|
Thompson CM, Malone JG. Nucleotide second messengers in bacterial decision making. Curr Opin Microbiol 2020; 55:34-39. [PMID: 32172083 PMCID: PMC7322531 DOI: 10.1016/j.mib.2020.02.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 02/04/2020] [Accepted: 02/10/2020] [Indexed: 12/28/2022]
Abstract
Structural analysis of NSM regulators reveals new mechanisms of NSM signalling. NSM proteins binding multiple ligands support crosstalk between signalling networks. NSM networks control structure and heterogeneity in complex microbial communities. The diversity of bacterial NSM regulators is far higher than previously thought. The (p)ppApp toxin suggests non-signalling roles exist for bacterial NSMs.
Since the initial discovery of bacterial nucleotide second messengers (NSMs), we have made huge progress towards understanding these complex signalling networks. Many NSM networks contain dozens of metabolic enzymes and binding targets, whose activity is tightly controlled at every regulatory level. They function as global regulators and in specific signalling circuits, controlling multiple aspects of bacterial behaviour and development. Despite these advances there is much still to discover, with current research focussing on the molecular mechanisms of signalling circuits, the role of the environment in controlling NSM pathways and attempts to understand signalling at the whole cell/community level. Here we examine recent developments in the NSM signalling field and discuss their implications for understanding this important driver of microbial behaviour.
Collapse
Affiliation(s)
- Catriona Ma Thompson
- Molecular Microbiology Department, John Innes Centre, Norwich, UK; School of Biological Sciences, University of East Anglia, Norwich, UK
| | - Jacob G Malone
- Molecular Microbiology Department, John Innes Centre, Norwich, UK; School of Biological Sciences, University of East Anglia, Norwich, UK.
| |
Collapse
|
38
|
Chouhan OP, Roske Y, Heinemann U, Biswas S. Structure of the active GGEEF domain of a diguanylate cyclase from Vibrio cholerae. Biochem Biophys Res Commun 2019; 523:287-292. [PMID: 31862141 DOI: 10.1016/j.bbrc.2019.11.179] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2019] [Accepted: 11/26/2019] [Indexed: 01/05/2023]
Abstract
Cyclic-di-GMP (c-di-GMP) synthesized by diguanylate cyclases has been an important and ubiquitous secondary messenger in almost all bacterial systems. In Vibrio cholerae, c-di-GMP plays an intricate role in the production of the exopolysaccharide matrix, and thereby, in biofilm formation. The formation of the surface biofilm enables the bacteria to survive in aquatic bodies, when not infecting a human host. Diguanylate cyclases are the class of enzymes which synthesize c-di-GMP from two molecules of GTP and are endowed with a GGDEF or, a GGEEF signature domain. The VC0395_0300 protein from V. cholerae, has been established as a diguanylate cyclase with a necessary role in biofilm formation. Here we present the structure of an N-terminally truncated form of VC0395_0300, which retains the active GGEEF domain for diguanylate cyclase activity but lacks 160 residues from the poorly organized N-terminal domain. X-ray diffraction data was collected from a crystal of VC0395_0300(161-321) to a resolution of 1.9 Å. The structure displays remarkable topological similarity with diguanylate cyclases from other bacterial systems, but lacks the binding site for c-di-GMP present in its homologues. Finally, we demonstrate the ability of the truncated diguanylate cyclase VC0395_0300(161-321) to produce c-di-GMP, and its role in biofilm formation for the bacteria.
Collapse
Affiliation(s)
| | - Yvette Roske
- Macromolecular Structure and Interaction Laboratory, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Udo Heinemann
- Macromolecular Structure and Interaction Laboratory, Max Delbrück Center for Molecular Medicine, Berlin, Germany; Chemistry and Biochemistry Institute, Freie Universität, Berlin, Germany
| | - Sumit Biswas
- ViStA Lab, BITS, Pilani - K K Birla Goa Campus, Zuarinagar, Goa, India.
| |
Collapse
|
39
|
Noirot-Gros MF, Forrester S, Malato G, Larsen PE, Noirot P. CRISPR interference to interrogate genes that control biofilm formation in Pseudomonas fluorescens. Sci Rep 2019; 9:15954. [PMID: 31685917 PMCID: PMC6828691 DOI: 10.1038/s41598-019-52400-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Accepted: 10/12/2019] [Indexed: 12/11/2022] Open
Abstract
Bacterial biofilm formation involves signaling and regulatory pathways that control the transition from motile to sessile lifestyle, production of extracellular polymeric matrix, and maturation of the biofilm 3D structure. Biofilms are extensively studied because of their importance in biomedical, ecological and industrial settings. Gene inactivation is a powerful approach for functional studies but it is often labor intensive, limiting systematic gene surveys to the most tractable bacterial hosts. Here, we adapted the CRISPR interference (CRISPRi) system for use in diverse strain isolates of P. fluorescens, SBW25, WH6 and Pf0-1. We found that CRISPRi is applicable to study complex phenotypes such as cell morphology, motility and biofilm formation over extended periods of time. In SBW25, CRISPRi-mediated silencing of genes encoding the GacA/S two-component system and regulatory proteins associated with the cylic di-GMP signaling messenger produced swarming and biofilm phenotypes similar to those obtained after gene inactivation. Combined with detailed confocal microscopy of biofilms, our study also revealed novel phenotypes associated with extracellular matrix biosynthesis as well as the potent inhibition of SBW25 biofilm formation mediated by the PFLU1114 operon. We conclude that CRISPRi is a reliable and scalable approach to investigate gene networks in the diverse P. fluorescens group.
Collapse
Affiliation(s)
| | - Sara Forrester
- Biosciences Division, Argonne National Laboratory, Lemont, IL60439, United States
| | - Grace Malato
- Biosciences Division, Argonne National Laboratory, Lemont, IL60439, United States
| | - Peter E Larsen
- Biosciences Division, Argonne National Laboratory, Lemont, IL60439, United States.,Department of Bioengineering, University of Illinois Chicago, Chicago, IL60607, United States
| | - Philippe Noirot
- Biosciences Division, Argonne National Laboratory, Lemont, IL60439, United States
| |
Collapse
|
40
|
Flagellar Stators Stimulate c-di-GMP Production by Pseudomonas aeruginosa. J Bacteriol 2019; 201:JB.00741-18. [PMID: 30642992 DOI: 10.1128/jb.00741-18] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 01/07/2019] [Indexed: 01/29/2023] Open
Abstract
Flagellar motility is critical for surface attachment and biofilm formation in many bacteria. A key regulator of flagellar motility in Pseudomonas aeruginosa and other microbes is cyclic diguanylate (c-di-GMP). High levels of this second messenger repress motility and stimulate biofilm formation. c-di-GMP levels regulate motility in P. aeruginosa in part by influencing the localization of its two flagellar stator sets, MotAB and MotCD. Here, we show that while c-di-GMP can influence stator localization, stators can in turn impact c-di-GMP levels. We demonstrate that the swarming motility-driving stator MotC physically interacts with the transmembrane region of the diguanylate cyclase SadC. Furthermore, we demonstrate that this interaction is capable of stimulating SadC activity. We propose a model by which the MotCD stator set interacts with SadC to stimulate c-di-GMP production under conditions not permissive to motility. This regulation implies a positive-feedback loop in which c-di-GMP signaling events cause MotCD stators to disengage from the motor; then disengaged stators stimulate c-di-GMP production to reinforce a biofilm mode of growth. Our studies help to define the bidirectional interactions between c-di-GMP and the flagellar machinery.IMPORTANCE The ability of bacterial cells to control motility during early steps in biofilm formation is critical for the transition to a nonmotile, biofilm lifestyle. Recent studies have clearly demonstrated the ability of c-di-GMP to control motility via a number of mechanisms, including through controlling transcription of motility-related genes and modulating motor function. Here, we provide evidence that motor components can in turn impact c-di-GMP levels. We propose that communication between motor components and the c-di-GMP synthesis machinery allows the cell to have a robust and sensitive switching mechanism to control motility during early events in biofilm formation.
Collapse
|
41
|
Xu G, Han S, Huo C, Chin KH, Chou SH, Gomelsky M, Qian G, Liu F. Signaling specificity in the c-di-GMP-dependent network regulating antibiotic synthesis in Lysobacter. Nucleic Acids Res 2019; 46:9276-9288. [PMID: 30202891 PMCID: PMC6182147 DOI: 10.1093/nar/gky803] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 08/28/2018] [Indexed: 12/31/2022] Open
Abstract
Enzymes controlling intracellular second messengers in bacteria, such as c-di-GMP, often affect some but not other targets. How such specificity is achieved is understood only partially. Here, we present a novel mechanism that enables specific c-di-GMP-dependent inhibition of the antifungal antibiotic production. Expression of the biosynthesis operon for Heat-Stable Antifungal Factor, HSAF, in Lysobacter enzymogenes occurs when the transcription activator Clp binds to two upstream sites. At high c-di-GMP levels, Clp binding to the lower-affinity site is compromised, which is sufficient to decrease gene expression. We identified a weak c-di-GMP phosphodiesterase, LchP, that plays a disproportionately high role in HSAF synthesis due to its ability to bind Clp. Further, Clp binding stimulates phosphodiesterase activity of LchP. An observation of a signaling complex formed by a c-di-GMP phosphodiesterase and a c-di-GMP-binding transcription factor lends support to the emerging paradigm that such signaling complexes are common in bacteria, and that bacteria and eukaryotes employ similar solutions to the specificity problem in second messenger-based signaling systems.
Collapse
Affiliation(s)
- Gaoge Xu
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China/Key Laboratory of Integrated Management of Crop Diseases and Pests (Nanjing Agricultural University), Ministry of Education, Nanjing 210014, P.R. China.,Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, P.R. China
| | - Sen Han
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China/Key Laboratory of Integrated Management of Crop Diseases and Pests (Nanjing Agricultural University), Ministry of Education, Nanjing 210014, P.R. China
| | - Cuimei Huo
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China/Key Laboratory of Integrated Management of Crop Diseases and Pests (Nanjing Agricultural University), Ministry of Education, Nanjing 210014, P.R. China
| | - Ko-Hsin Chin
- Institute of Biochemistry, and NCHU Agricultural Biotechnology Center, National Chung Hsing University, Taichung, Taiwan, ROC
| | - Shan-Ho Chou
- Institute of Biochemistry, and NCHU Agricultural Biotechnology Center, National Chung Hsing University, Taichung, Taiwan, ROC
| | - Mark Gomelsky
- Department of Molecular Biology, University of Wyoming, Laramie, Wyoming 82071, USA
| | - Guoliang Qian
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China/Key Laboratory of Integrated Management of Crop Diseases and Pests (Nanjing Agricultural University), Ministry of Education, Nanjing 210014, P.R. China
| | - Fengquan Liu
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, P.R. China
| |
Collapse
|
42
|
Li H, Xue D, Tian F, Yuan X, Yang F, Chen H, Hutchins W, Yang CH, He C. Xanthomonas oryzae pv. oryzae Response Regulator TriP Regulates Virulence and Exopolysaccharide Production Via Interacting With c-di-GMP Phosphodiesterase PdeR. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2019; 32:729-739. [PMID: 30589364 DOI: 10.1094/mpmi-09-18-0260-r] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
PdeR, a response regulator of the two-component system (TCS) with the cognate histidine kinase PdeK, has been shown to be an active phosphodiesterase (PDE) for intracellular cyclic dimeric guanosine monophosphate (c-di-GMP) turnover and positively regulates the virulence of Xanthomonas oryzae pv. oryzae, the causal pathogen of bacterial blight of rice. To further reveal the key components and pathways involved in the PdeR-mediated c-di-GMP regulation of virulence, 16 PdeR-interacting proteins were identified, using the yeast two-hybrid (Y2H) assay. Among them, PXO_04421 (named as TriP, a putative transcriptional regulator interacting with PdeR) was verified via Y2H and glutathione-S-transferase pull-down assays, and its regulatory functions in bacterial virulence and exopolysaccharide (EPS) production were assessed by biochemical and genetic analysis. The REC domain of TriP specifically interacted with the EAL domain of PdeR. TriP promoted the PDE activity of PdeR to degrade c-di-GMP in the presence of PdeK. In-frame deletion in triP abolished the polar localization of PdeR in the cell. Notably, the ∆triP mutant showed significantly reduced virulence on susceptible rice leaves and impaired EPS production compared with wild type, whereas the double mutant ∆triP∆pdeR, like ∆pdeR, caused shorter lesion lengths and produced less EPS than ∆triP. In addition, cross-complementation showed in trans expression of pdeR in ∆triP restored its EPS production to near wild-type levels but not vice versa. Taken together, our results suggest that TriP is a novel regulator that is epistatic to PdeR in positively regulating virulence expression in X. oryzae pv. oryzae.
Collapse
Affiliation(s)
- Haiyun Li
- 1 State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
- 2 Jingtang Port Office of Hebei Entry-Exit Inspection and Quarantine Bureau, Tangshan 063611, China
| | - Dingrong Xue
- 1 State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Fang Tian
- 1 State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Xiaochen Yuan
- 3 Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI 53211, U.S.A
| | - Fenghuan Yang
- 1 State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Huamin Chen
- 1 State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | | | - Ching-Hong Yang
- 3 Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI 53211, U.S.A
| | - Chenyang He
- 1 State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| |
Collapse
|
43
|
Pfiffer V, Sarenko O, Possling A, Hengge R. Genetic dissection of Escherichia coli's master diguanylate cyclase DgcE: Role of the N-terminal MASE1 domain and direct signal input from a GTPase partner system. PLoS Genet 2019; 15:e1008059. [PMID: 31022167 PMCID: PMC6510439 DOI: 10.1371/journal.pgen.1008059] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Revised: 05/10/2019] [Accepted: 02/28/2019] [Indexed: 11/18/2022] Open
Abstract
The ubiquitous second messenger c-di-GMP promotes bacterial biofilm formation by playing diverse roles in the underlying regulatory networks. This is reflected in the multiplicity of diguanylate cyclases (DGC) and phosphodiesterases (PDE) that synthesize and degrade c-di-GMP, respectively, in most bacterial species. One of the 12 DGCs of Escherichia coli, DgcE, serves as the top-level trigger for extracellular matrix production during macrocolony biofilm formation. Its multi-domain architecture–a N-terminal membrane-inserted MASE1 domain followed by three PAS, a GGDEF and a degenerate EAL domain–suggested complex signal integration and transmission through DgcE. Genetic dissection of DgcE revealed activating roles for the MASE1 domain and the dimerization-proficient PAS3 region, whereas the inhibitory EALdeg domain counteracts the formation of DgcE oligomers. The MASE1 domain is directly targeted by the GTPase RdcA (YjdA), a dimer or oligomer that together with its partner protein RdcB (YjcZ) activates DgcE, probably by aligning and promoting dimerization of the PAS3 and GGDEF domains. This activation and RdcA/DgcE interaction depend on GTP hydrolysis by RdcA, suggesting GTP as an inhibitor and the pronounced decrease of the cellular GTP pool during entry into stationary phase, which correlates with DgcE-dependent activation of matrix production, as a possible input signal sensed by RdcA. Furthermore, DgcE exhibits rapid, continuous and processive proteolytic turnover that also depends on the relatively disordered transmembrane MASE1 domain. Overall, our study reveals a novel GTP/c-di-GMP-connecting signaling pathway through the multi-domain DGC DgcE with a dual role for the previously uncharacterized MASE1 signaling domain. Biofilms represent a multicellular life form of bacteria, in which large numbers of cells live in communities surrounded and protected by a self-generated extracellular polymeric matrix. As biofilms tolerate antibiotics and host immune systems, they are causally associated with chronic infections. Biofilm formation is generally promoted by the ubiquitous bacterial second messenger c-di-GMP. DgcE, one of the 12 diguanylate cyclases that produce c-di-GMP in E. coli, was previously shown to specifically act as a top level trigger in the regulatory network that drives biofilm matrix production in this bacterium. However, signal input into DgcE itself, which is a large six-domain protein, had remained unknown. Here we demonstrate that DgcE activity is controlled by a novel type of dynamin-like GTPase that directly interacts with the N-terminal membrane-intrinsic MASE1 domain of DgcE. Our finding of a dual function of this MASE1 domain, which is essential for both activation and continuous proteolysis of DgcE, is the first characterization of this widespread bacterial signaling domain. Signal input via the dynamin-like GTPase system suggests that c-di-GMP production by DgcE might be stimulated by the decreasing cellular GTP level during entry into stationary phase, which is precisely the time when biofilm matrix production is turned on.
Collapse
Affiliation(s)
- Vanessa Pfiffer
- Institut für Biologie / Mikrobiologie, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Olga Sarenko
- Institut für Biologie / Mikrobiologie, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Alexandra Possling
- Institut für Biologie / Mikrobiologie, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Regine Hengge
- Institut für Biologie / Mikrobiologie, Humboldt-Universität zu Berlin, Berlin, Germany
| |
Collapse
|
44
|
Pérez-Mendoza D, Felipe A, Ferreiro MD, Sanjuán J, Gallegos MT. AmrZ and FleQ Co-regulate Cellulose Production in Pseudomonas syringae pv. Tomato DC3000. Front Microbiol 2019; 10:746. [PMID: 31057500 PMCID: PMC6478803 DOI: 10.3389/fmicb.2019.00746] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 03/25/2019] [Indexed: 12/28/2022] Open
Abstract
Pseudomonas syringae pv. tomato DC3000 carries the wssABCDEFGHI operon for the synthesis of acetylated cellulose, whose production is stimulated by increasing the intracellular levels of the second messenger c-di-GMP. This enhances air-liquid biofilm formation and generates a wrinkly colony morphotype in solid media. In the present study we show that cellulose production is a complex process regulated at multiple levels and involving different players in this bacterium. Using different in vitro approaches, including Electrophoretic Mobility Shift Assay (EMSA) and footprint analysis, we demonstrated the interrelated role of two transcriptional regulators, AmrZ and FleQ, over cellulose production in Pto DC3000 and the influence of c-di-GMP in this process. Under physiological c-di-GMP levels, both regulators bind directly to adjacent regions at the wss promoter inhibiting its expression. However, just FleQ responds to c-di-GMP releasing from its wss operator site and converting from a repressor to an activator of cellulose production. The additive effect of the double amrZ/fleQ mutation on the expression of wss, together with the fact that they are not cross-regulated at the transcriptional level, suggest that FleQ and AmrZ behave as independent regulators, unlike what has been described in other Pseudomonas species. Furthermore, this dual co-regulation exerted by AmrZ and FleQ is not limited to cellulose production, but also affects other important phenotypes in Pto DC3000, such as motility and virulence.
Collapse
Affiliation(s)
- Daniel Pérez-Mendoza
- Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidín (EEZ-CSIC), Granada, Spain
| | - Antonia Felipe
- Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidín (EEZ-CSIC), Granada, Spain
| | - María Dolores Ferreiro
- Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidín (EEZ-CSIC), Granada, Spain
| | - Juan Sanjuán
- Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidín (EEZ-CSIC), Granada, Spain
| | - María Trinidad Gallegos
- Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidín (EEZ-CSIC), Granada, Spain
| |
Collapse
|
45
|
Serra DO, Hengge R. A c-di-GMP-Based Switch Controls Local Heterogeneity of Extracellular Matrix Synthesis which Is Crucial for Integrity and Morphogenesis of Escherichia coli Macrocolony Biofilms. J Mol Biol 2019; 431:4775-4793. [PMID: 30954572 DOI: 10.1016/j.jmb.2019.04.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 03/26/2019] [Accepted: 04/01/2019] [Indexed: 12/14/2022]
Abstract
The extracellular matrix in macrocolony biofilms of Escherichia coli is arranged in a complex large-scale architecture, with homogenic matrix production close to the surface, whereas zones further below display pronounced local heterogeneity of matrix production, which results in distinct three-dimensional architectural structures. Combining genetics, cryosectioning and fluorescence microscopy of macrocolony biofilms, we demonstrate here in situ that this local matrix heterogeneity is generated by a c-di-GMP-dependent molecular switch characterized by several nested positive and negative feedback loops. In this switch, the trigger phosphodiesterase PdeR is the key component for establishing local heterogeneity in the activation of the transcription factor MlrA, which in turn activates expression of the major matrix regulator CsgD. Upon its release of direct inhibition by PdeR, the second switch component, the diguanylate cyclase DgcM, activates MlrA by direct interaction. Antagonistically acting PdeH and DgcE provide for a PdeR-sensed c-di-GMP input into this switch and-via their spatially differentially controlled expression-generate the long-range vertical asymmetry of the matrix architecture. Using flow cytometry, we show heterogeneity of CsgD expression to also occur in spatially unstructured planktonic cultures, where it is controlled by the same c-di-GMP circuitry as in macrocolony biofilms. Quantification by flow cytometry also showed CsgDON subpopulations with distinct CsgD expression levels and revealed an additional fine-tuning feedback within the PdeR/DgcM-mediated switch that depends on c-di-GMP synthesis by DgcM. Finally, local heterogeneity of matrix production was found to be crucial for the tissue-like elasticity that allows for large-scale wrinkling and folding of macrocolony biofilms.
Collapse
Affiliation(s)
- Diego O Serra
- Institut für Biologie/Mikrobiologie, Humboldt-Universität zu Berlin, 10115 Berlin, Germany
| | - Regine Hengge
- Institut für Biologie/Mikrobiologie, Humboldt-Universität zu Berlin, 10115 Berlin, Germany.
| |
Collapse
|
46
|
Waldron EJ, Snyder D, Fernandez NL, Sileo E, Inoyama D, Freundlich JS, Waters CM, Cooper VS, Neiditch MB. Structural basis of DSF recognition by its receptor RpfR and its regulatory interaction with the DSF synthase RpfF. PLoS Biol 2019; 17:e3000123. [PMID: 30716063 PMCID: PMC6361424 DOI: 10.1371/journal.pbio.3000123] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 01/10/2019] [Indexed: 01/07/2023] Open
Abstract
The diffusible signal factors (DSFs) are a family of quorum-sensing autoinducers (AIs) produced and detected by numerous gram-negative bacteria. The DSF family AIs are fatty acids, differing in their acyl chain length, branching, and substitution but having in common a cis-2 double bond that is required for their activity. In both human and plant pathogens, DSFs regulate diverse phenotypes, including virulence factor expression, antibiotic resistance, and biofilm dispersal. Despite their widespread relevance to both human health and agriculture, the molecular basis of DSF recognition by their cellular receptors remained a mystery. Here, we report the first structure-function studies of the DSF receptor regulation of pathogenicity factor R (RpfR). We present the X-ray crystal structure of the RpfR DSF-binding domain in complex with the Burkholderia DSF (BDSF), which to our knowledge is the first structure of a DSF receptor in complex with its AI. To begin to understand the mechanistic role of the BDSF-RpfR contacts observed in the biologically important complex, we have also determined the X-ray crystal structure of the RpfR DSF-binding domain in complex with the inactive, saturated isomer of BDSF, dodecanoic acid (C12:0). In addition to these ligand-receptor complex structures, we report the discovery of a previously overlooked RpfR domain and show that it binds to and negatively regulates the DSF synthase regulation of pathogenicity factor F (RpfF). We have named this RpfR region the RpfF interaction (FI) domain, and we have determined its X-ray crystal structure alone and in complex with RpfF. These X-ray crystal structures, together with extensive complementary in vivo and in vitro functional studies, reveal the molecular basis of DSF recognition and the importance of the cis-2 double bond to DSF function. Finally, we show that throughout cellular growth, the production of BDSF by RpfF is post-translationally controlled by the RpfR N-terminal FI domain, affecting the cellular concentration of the bacterial second messenger bis-(3'-5')-cyclic dimeric guanosine monophosphate (c-di-GMP). Thus, in addition to describing the molecular basis for the binding and specificity of a DSF for its receptor, we describe a receptor-synthase interaction regulating bacterial quorum-sensing signaling and second messenger signal transduction.
Collapse
Affiliation(s)
- Evan J. Waldron
- Department of Microbiology, Biochemistry, and Molecular Genetics, New Jersey Medical School, Rutgers, State University of New Jersey, Newark, New Jersey, United States of America
| | - Daniel Snyder
- Department of Microbiology and Molecular Genetics, and Center for Evolutionary Biology and Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Nicolas L. Fernandez
- Department of Microbiology and Molecular Genetics and the BEACON Center for the Study of Evolution in Action, Michigan State University, East Lansing, Michigan, United States of America
| | - Emily Sileo
- Department of Microbiology and Molecular Genetics, and Center for Evolutionary Biology and Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Daigo Inoyama
- Department of Pharmacology, Physiology, and Neuroscience, New Jersey Medical School, Rutgers, State University of New Jersey, Newark, New Jersey, United States of America
| | - Joel S. Freundlich
- Department of Pharmacology, Physiology, and Neuroscience, New Jersey Medical School, Rutgers, State University of New Jersey, Newark, New Jersey, United States of America
| | - Christopher M. Waters
- Department of Microbiology and Molecular Genetics and the BEACON Center for the Study of Evolution in Action, Michigan State University, East Lansing, Michigan, United States of America
| | - Vaughn S. Cooper
- Department of Microbiology and Molecular Genetics, and Center for Evolutionary Biology and Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Matthew B. Neiditch
- Department of Microbiology, Biochemistry, and Molecular Genetics, New Jersey Medical School, Rutgers, State University of New Jersey, Newark, New Jersey, United States of America
- * E-mail:
| |
Collapse
|
47
|
Recent Advances and Current Trends in Nucleotide Second Messenger Signaling in Bacteria. J Mol Biol 2019; 431:908-927. [PMID: 30668970 DOI: 10.1016/j.jmb.2019.01.014] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 01/05/2019] [Accepted: 01/07/2019] [Indexed: 02/01/2023]
Abstract
The "International Symposium on Nucleotide Second Messenger Signaling in Bacteria" (September 30-October 3, 2018, Berlin), which was organized within the framework of DFG Priority Programme 1879 (www.spp1879.de), brought together 125 participants from 20 countries to discuss recent progress and future trends in this field. Even 50 years after its discovery, (p)ppGpp is venturing into exciting new fields, especially in gram-positive bacteria. After triggering the current renaissance in bacterial second messenger research, c-di-GMP is becoming ever more global with abounding new molecular mechanisms of action and physiological functions. The more recently discovered c-di-AMP is rapidly catching up and has now been found even in archaea, with its function in osmotic homeostasis being conserved across kingdom boundaries. Small modules associated with mobile genetic elements, which make and react to numerous novel mixed cyclic dinucleotides, seem to roam around rather freely in the bacterial world. Finally, many novel and old nucleotide molecules are still lurking around in search of a function. Across many talks it became apparent that (p)ppGpp, c-di-GMP and GTP/ATP can share and compete for binding sites (e.g., the Walker A motif in GTP/ATPases) with intriguing regulatory consequences, thus contributing to the emergent trend of systemwide networks that interconnect diverse signaling nucleotides. Overall, this inspiring conference made it clear that second messenger signaling is currently one of the most dynamic and exciting areas in microbial molecular biology and physiology, with major impacts ranging from microbial systems biology and ecology to infection biology.
Collapse
|
48
|
Golonka R, Yeoh BS, Vijay-Kumar M. The Iron Tug-of-War between Bacterial Siderophores and Innate Immunity. J Innate Immun 2019; 11:249-262. [PMID: 30605903 DOI: 10.1159/000494627] [Citation(s) in RCA: 92] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Accepted: 09/20/2018] [Indexed: 12/21/2022] Open
Abstract
Iron is necessary for the survival of almost all aerobic organisms. In the mammalian host, iron is a required cofactor for the assembly of functional iron-sulfur (Fe-S) cluster proteins, heme-binding proteins and ribonucleotide reductases that regulate various functions, including heme synthesis, oxygen transport and DNA synthesis. However, the bioavailability of iron is low due to its insolubility under aerobic conditions. Moreover, the host coordinates a nutritional immune response to restrict the accessibility of iron against potential pathogens. To counter nutritional immunity, most commensal and pathogenic bacteria synthesize and secrete small iron chelators termed siderophores. Siderophores have potent affinity for iron, which allows them to seize the essential metal from the host iron-binding proteins. To safeguard against iron thievery, the host relies upon the innate immune protein, lipocalin 2 (Lcn2), which could sequester catecholate-type siderophores and thus impede bacterial growth. However, certain bacteria are capable of outmaneuvering the host by either producing "stealth" siderophores or by expressing competitive antagonists that bind Lcn2 in lieu of siderophores. In this review, we summarize the mechanisms underlying the complex iron tug-of-war between host and bacteria with an emphasis on how host innate immunity responds to siderophores.
Collapse
Affiliation(s)
- Rachel Golonka
- Department of Physiology and Pharmacology, University of Toledo College of Medicine and Life Sciences, Toledo, Ohio, USA
| | - Beng San Yeoh
- Graduate Program in Immunology and Infectious Disease, Pennsylvania State University, University Park, Pennsylvania, USA
| | - Matam Vijay-Kumar
- Department of Physiology and Pharmacology, University of Toledo College of Medicine and Life Sciences, Toledo, Ohio, USA, .,Department of Medical Microbiology and Immunology, University of Toledo College of Medicine and Life Sciences, Toledo, Ohio, USA,
| |
Collapse
|
49
|
|
50
|
An SQ, Ding YC, Faber F, Hobley L, Sá-Pessoa J. Social behaviour and making attachments: a report from the fifth 'Young Microbiologists Symposium on Microbe Signalling, Organisation and Pathogenesis'. MICROBIOLOGY-SGM 2018; 165:138-145. [PMID: 30520711 DOI: 10.1099/mic.0.000746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The fifth Young Microbiologists Symposium was held in Queen's University Belfast, Northern Ireland, in late August 2018. The symposium, focused on 'Microbe signalling, organization and pathogenesis', attracted 121 microbiologists from 15 countries. The meeting allowed junior scientists to present their work to a broad audience, and was supported by the European Molecular Biology Organization, the Federation of European Microbiological Societies, the Society of Applied Microbiology, the Biochemical Society and the Microbiology Society. Sessions covered recent advances in areas of microbiology including gene regulation and signalling, secretion and transport across membranes, infection and immunity, and antibiotics and resistance mechanisms. In this Meeting Report, we highlight some of the most significant advances and exciting developments communicated during talks and poster presentations.
Collapse
Affiliation(s)
- Shi-Qi An
- 1Wellcome-Wolfson Institute for Experimental Medicine, Queen's University Belfast, Belfast, UK.,2Biological Sciences, University of Southampton, Southampton, UK
| | - Yi-Chen Ding
- 3Singapore Centre for Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, Singapore 637551, Asia
| | - Franziska Faber
- 4Institute of Molecular Infection Biology, University of Würzburg, Würzburg, German
| | - Laura Hobley
- 5School of Biosciences, University of Nottingham, Nottingham, UK
| | - Joana Sá-Pessoa
- 1Wellcome-Wolfson Institute for Experimental Medicine, Queen's University Belfast, Belfast, UK
| |
Collapse
|