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Zhang Y, Zhang T, Qiu Y, Zhang M, Lu X, Yang W, Hu L, Zhou D, Gao B, Lu R. Transcriptomic Profiles of Vibrio parahaemolyticus During Biofilm Formation. Curr Microbiol 2023; 80:371. [PMID: 37838636 DOI: 10.1007/s00284-023-03425-7] [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: 05/03/2023] [Accepted: 07/19/2023] [Indexed: 10/16/2023]
Abstract
Vibrio parahaemolyticus, the leading cause of bacterial seafood-associated gastroenteritis, can form biofilms. In this work, the gene expression profiles of V. parahaemolyticus during biofilm formation were investigated by transcriptome sequencing. A total of 183, 503, and 729 genes were significantly differentially expressed in the bacterial cells at 12, 24 and 48 h, respectively, compared with that at 6 h. Of these, 92 genes were consistently activated or repressed from 6 to 48 h. The genes involved in polar flagellum, chemotaxis, mannose-sensitive haemagglutinin type IV pili, capsular polysaccharide, type III secretion system 1 (T3SS1), T3SS2, thermostable direct hemolysin (TDH), type VI secretion system 1 (T6SS1) and T6SS2 were downregulated, whereas those involved in V. parahaemolyticus pathogenicity island (Vp-PAI) (except for T3SS2 and TDH) and membrane fusion proteins were upregulated. Three extracellular protease genes (vppC, prtA and VPA1071) and a dozen of outer membrane protein encoding genes were also significantly differentially expressed during biofilm formation. In addition, five putative c-di-GMP metabolism-associated genes were significantly differentially expressed, which may account for the drop in c-di-GMP levels after the beginning of biofilm formation. Moreover, many putative regulatory genes were significantly differentially expressed, and more than 1000 putative small non-coding RNAs were detected, suggesting that biofilm formation was tightly regulated by complex regulatory networks. The data provided a global view of gene expression profiles during biofilm formation, showing that the significantly differentially expressed genes were involved in multiple cellular pathways, including virulence, biofilm formation, metabolism, and regulation.
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Affiliation(s)
- Yiquan Zhang
- Department of Clinical Laboratory, Affiliated Nantong Hospital 3 of Nantong University, Nantong, 226006, Jiangsu, China
- Department of Clinical Laboratory, Nantong Third People's Hospital, Nantong, 226006, Jiangsu, China
| | - Tingting Zhang
- Department of Clinical Laboratory, Affiliated Nantong Hospital 3 of Nantong University, Nantong, 226006, Jiangsu, China
- Department of Clinical Laboratory, Nantong Third People's Hospital, Nantong, 226006, Jiangsu, China
| | - Yue Qiu
- Department of Clinical Laboratory, The Affiliated Changzhou No.2 People's Hospital of Nanjing Medical University, Changzhou, 213000, Jiangsu, China
| | - Miaomiao Zhang
- Department of Clinical Laboratory, Affiliated Nantong Hospital 3 of Nantong University, Nantong, 226006, Jiangsu, China
- Department of Clinical Laboratory, Nantong Third People's Hospital, Nantong, 226006, Jiangsu, China
| | - Xiuhui Lu
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China
| | - Wenhui Yang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China
| | - Lingfei Hu
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China
| | - Dongsheng Zhou
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China
| | - Bo Gao
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China.
| | - Renfei Lu
- Department of Clinical Laboratory, Affiliated Nantong Hospital 3 of Nantong University, Nantong, 226006, Jiangsu, China.
- Department of Clinical Laboratory, Nantong Third People's Hospital, Nantong, 226006, Jiangsu, China.
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Yu M, Hu S, Tang B, Yang H, Sun D. Engineering Escherichia coli Nissle 1917 as a microbial chassis for therapeutic and industrial applications. Biotechnol Adv 2023; 67:108202. [PMID: 37343690 DOI: 10.1016/j.biotechadv.2023.108202] [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: 12/08/2022] [Revised: 05/19/2023] [Accepted: 06/17/2023] [Indexed: 06/23/2023]
Abstract
Genetically engineered microbes, especially Escherichia coli, have been widely used in the biosynthesis of proteins and metabolites for medical and industrial applications. As a traditional probiotic with a well-established safety record, E. coli Nissle 1917 (EcN) has recently emerged as a microbial chassis for generating living therapeutics, drug delivery vehicles, and microbial platforms for industrial production. Despite the availability of genetic tools for engineering laboratory E. coli K-12 and B strains, new genetic engineering systems are still greatly needed to expand the application range of EcN. In this review, we have summarized the latest progress in the development of genetic engineering systems in EcN, as well as their applications in the biosynthesis and delivery of valuable small molecules and biomacromolecules of medical and/or industrial interest, followed by a glimpse of how this rapidly growing field will evolve in the future.
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Affiliation(s)
- Mingjing Yu
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, Zhejiang 310014, China
| | - Shilong Hu
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, Zhejiang 310014, China
| | - Biao Tang
- Institute of Quality and Standard for Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, Zhejiang, China
| | - Hua Yang
- Institute of Quality and Standard for Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, Zhejiang, China
| | - Dongchang Sun
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, Zhejiang 310014, China.
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Sano K, Kobayashi H, Chuta H, Matsuyoshi N, Kato Y, Ogasawara H. CsgI (YccT) Is a Novel Inhibitor of Curli Fimbriae Formation in Escherichia coli Preventing CsgA Polymerization and Curli Gene Expression. Int J Mol Sci 2023; 24:ijms24054357. [PMID: 36901788 PMCID: PMC10002515 DOI: 10.3390/ijms24054357] [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: 12/31/2022] [Revised: 02/16/2023] [Accepted: 02/20/2023] [Indexed: 02/25/2023] Open
Abstract
Curli fimbriae are amyloids-found in bacteria (Escherichia coli)-that are involved in solid-surface adhesion and bacterial aggregation during biofilm formation. The curli protein CsgA is coded by a csgBAC operon gene, and the transcription factor CsgD is essential to induce its curli protein expression. However, the complete mechanism underlying curli fimbriae formation requires elucidation. Herein, we noted that curli fimbriae formation was inhibited by yccT-i.e., a gene that encodes a periplasmic protein of unknown function regulated by CsgD. Furthermore, curli fimbriae formation was strongly repressed by CsgD overexpression caused by a multicopy plasmid in BW25113-the non-cellulose-producing strain. YccT deficiency prevented these CsgD effects. YccT overexpression led to intracellular YccT accumulation and reduced CsgA expression. These effects were addressed by deleting the N-terminal signal peptide of YccT. Localization, gene expression, and phenotypic analyses revealed that YccT-dependent inhibition of curli fimbriae formation and curli protein expression was mediated by the two-component regulatory system EnvZ/OmpR. Purified YccT inhibited CsgA polymerization; however, no intracytoplasmic interaction between YccT and CsgA was detected. Thus, YccT-renamed CsgI (curli synthesis inhibitor)-is a novel inhibitor of curli fimbriae formation and has a dual role as an OmpR phosphorylation modulator and CsgA polymerization inhibitor.
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Affiliation(s)
- Kotaro Sano
- Research Center for Advanced Science and Technology, Division of Gene Research, Shinshu University, 3-15-1 Ueda, Nagano 386-8567, Japan
- Department of Applied Biology, Graduated School of Science and Technology, Shinshu University, 3-15-1 Ueda, Nagano 386-8567, Japan
| | - Hiroaki Kobayashi
- Research Center for Advanced Science and Technology, Division of Gene Research, Shinshu University, 3-15-1 Ueda, Nagano 386-8567, Japan
- Department of Applied Biology, Graduated School of Science and Technology, Shinshu University, 3-15-1 Ueda, Nagano 386-8567, Japan
| | - Hirotaka Chuta
- Research Center for Advanced Science and Technology, Division of Gene Research, Shinshu University, 3-15-1 Ueda, Nagano 386-8567, Japan
- Department of Applied Biology, Graduated School of Science and Technology, Shinshu University, 3-15-1 Ueda, Nagano 386-8567, Japan
| | - Nozomi Matsuyoshi
- Research Center for Advanced Science and Technology, Division of Gene Research, Shinshu University, 3-15-1 Ueda, Nagano 386-8567, Japan
- Department of Applied Biology, Graduated School of Science and Technology, Shinshu University, 3-15-1 Ueda, Nagano 386-8567, Japan
| | - Yuki Kato
- Research Center for Advanced Science and Technology, Division of Gene Research, Shinshu University, 3-15-1 Ueda, Nagano 386-8567, Japan
- Department of Applied Biology, Graduated School of Science and Technology, Shinshu University, 3-15-1 Ueda, Nagano 386-8567, Japan
| | - Hiroshi Ogasawara
- Research Center for Advanced Science and Technology, Division of Gene Research, Shinshu University, 3-15-1 Ueda, Nagano 386-8567, Japan
- Academic Assembly School of Humanities and Social Sciences Institute of Humanities, Shinshu University, Matsumoto 390-8621, Japan
- Institute for Fiber Engineering (IFES), Interdisciplinary Cluster for Cutting Edge Research (ICCER), Shinshu University, Tokida 3-15-1, Ueda, Nagano 386-8567, Japan
- Renaissance Center for Applied Microbiology, Shinshu University, Nagano-shi, Nagano 380-8553, Japan
- Correspondence: ; Tel.: +81-268-21-5803
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Azam MW, Khan AU. CRISPRi -mediated suppression of E. coli Nissle 1917 virulence factors: A strategy for creating an engineered probiotic using csgD gene suppression. Front Nutr 2022; 9:938989. [PMID: 35978963 PMCID: PMC9376613 DOI: 10.3389/fnut.2022.938989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2022] [Accepted: 06/29/2022] [Indexed: 11/13/2022] Open
Abstract
Background Biofilm formation is a complex phenomenon, and it is the causative agent of several human infections. Bacterial amyloids are involved in biofilm formation leading to infection persistence. Due to antibiotic resistance, their treatment is a great challenge for physicians. Probiotics, especially E. coli Nissle 1917 (EcN), are used to treat human intestinal disorders and ulcerative colitis. It also expresses virulence factors associated with biofilm and amyloid formation. EcN produces biofilm equivalent to the pathogenic UPEC strains. Methods CRISPRi was used to create the knockdown mutants of the csgD gene (csgD-KD). The qRT-PCR was performed to assess the expression of the csgD gene in csgD-KD cells. The csgD-KD cells were also evaluated for the expression of csgA, csgB, fimA, fimH, ompR, luxS, and bolA genes. The gene expression data obtained was further confirmed by spectroscopic, microscopic, and other assays to validate our study. Results CRISPRi-mediated knockdown of csgD gene shows reduction in curli amyloid formation, biofilm formation, and suppression of genes (csgA, csgB, fimA, fimH, ompR, bolA, and luxS) involved in virulence factors production. Conclusion Curli amyloid fibers and fimbriae fibers play a critical role in biofilm formation leading to pathogenicity. CsgD protein is the master regulator of curli synthesis in E. coli. Hence, curli amyloid inhibition through the csgD gene may be used to improve the EcN and different probiotic strains by suppressing virulence factors.
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Affiliation(s)
- Mohd W Azam
- Medical Microbiology and Molecular Biology Lab, Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, India
| | - Asad U Khan
- Medical Microbiology and Molecular Biology Lab, Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, India
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Metabolic adaption to extracellular pyruvate triggers biofilm formation in Clostridioides difficile. THE ISME JOURNAL 2021; 15:3623-3635. [PMID: 34155333 PMCID: PMC8630010 DOI: 10.1038/s41396-021-01042-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Revised: 06/09/2021] [Accepted: 06/11/2021] [Indexed: 02/06/2023]
Abstract
Clostridioides difficile infections are associated with gut microbiome dysbiosis and are the leading cause of hospital-acquired diarrhoea. The infectious process is strongly influenced by the microbiota and successful infection relies on the absence of specific microbiota-produced metabolites. Deoxycholate and short-chain fatty acids are microbiota-produced metabolites that limit the growth of C. difficile and protect the host against this infection. In a previous study, we showed that deoxycholate causes C. difficile to form strongly adherent biofilms after 48 h. Here, our objectives were to identify and characterize key molecules and events required for biofilm formation in the presence of deoxycholate. We applied time-course transcriptomics and genetics to identify sigma factors, metabolic processes and type IV pili that drive biofilm formation. These analyses revealed that extracellular pyruvate induces biofilm formation in the presence of deoxycholate. In the absence of deoxycholate, pyruvate supplementation was sufficient to induce biofilm formation in a process that was dependent on pyruvate uptake by the membrane protein CstA. In the context of the human gut, microbiota-generated pyruvate is a metabolite that limits pathogen colonization. Taken together our results suggest that pyruvate-induced biofilm formation might act as a key process driving C. difficile persistence in the gut.
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Ziegler M, Hägele L, Gäbele T, Takors R. CRISPRi enables fast growth followed by stable aerobic pyruvate formation in
Escherichia coli
without auxotrophy. Eng Life Sci 2021; 22:70-84. [PMID: 35140555 PMCID: PMC8811725 DOI: 10.1002/elsc.202100021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 10/06/2021] [Accepted: 11/10/2021] [Indexed: 11/13/2022] Open
Abstract
CRISPR interference (CRISPRi) was applied to enable the aerobic production of pyruvate in Escherichia coli MG1655 under glucose excess conditions by targeting the promoter regions of aceE or pdhR. Knockdown strains were cultivated in aerobic shaking flasks and the influence of inducer concentration and different sgRNA binding sites on the production of pyruvate was measured. Targeting the promoter regions of aceE or pdhR triggered pyruvate production during the exponential phase and reduced expression of aceE. In lab‐scale bioreactor fermentations, an aceE silenced strain successfully produced pyruvate under fully aerobic conditions during the exponential phase, but loss of productivity occurred during a subsequent nitrogen‐limited phase. Targeting the promoter region of pdhR enabled pyruvate production during the growth phase of cultivations, and a continued low‐level accumulation during the nitrogen‐limited production phase. Combinatorial targeting of the promoter regions of both aceE and pdhR in E. coli MG1655 pdCas9 psgRNA_aceE_234_pdhR_329 resulted in the stable aerobic production of pyruvate with non‐growing cells at YP/S = 0.36 ± 0.029 gPyruvate/gGlucose in lab‐scale bioreactors throughout an extended nitrogen‐limited production phase.
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Affiliation(s)
- Martin Ziegler
- Institute of Biochemical Engineering University of Stuttgart Stuttgart Germany
| | - Lorena Hägele
- Institute of Biochemical Engineering University of Stuttgart Stuttgart Germany
| | - Teresa Gäbele
- Institute of Biochemical Engineering University of Stuttgart Stuttgart Germany
| | - Ralf Takors
- Institute of Biochemical Engineering University of Stuttgart Stuttgart Germany
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First insights into a pyruvate sensing and uptake system in Vibrio campbellii and its importance for virulence. J Bacteriol 2021; 203:e0029621. [PMID: 34339295 DOI: 10.1128/jb.00296-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Pyruvate is a key metabolite in living cells and has been shown to play a crucial role in the virulence of several bacterial pathogens. The bioluminescent Vibrio campbellii, a severe infectious burden for marine aquaculture, excretes extraordinarily large amounts of pyruvate during growth and rapidly retrieves it by an as-yet unknown mechanism. We have now identified the responsible pyruvate transporter, here named BtsU, and our results show that it is the only pyruvate transporter in V. campbellii. Expression of btsU is tightly regulated by the membrane-integrated LytS-type histidine kinase BtsS, a sensor for extracellular pyruvate, and the LytTR-type response regulator BtsR. Cells lacking either the pyruvate transporter or sensing system show no chemotactic response towards pyruvate, indicating that intracellular pyruvate is required to activate the chemotaxis system. Moreover, pyruvate sensing and uptake were found to be important for the resuscitation of V. campbellii from the viable but nonculturable (VBNC) state and the bacterium's virulence against brine shrimp larvae. IMPORTANCE Bacterial infections are a serious threat to marine aquaculture, one of the fastest growing food sectors on earth. Therefore, it is extremely important to learn more about the pathogens responsible, one of which is Vibrio campbellii. This study sheds light on the importance of pyruvate sensing and uptake for V. campbellii, and reveals that the bacterium possesses only one pyruvate transporter, which is activated by a pyruvate-responsive histidine kinase/response regulator system. Without the ability to sense or take up pyruvate, the virulence of V. campbellii towards gnotobiotic brine shrimp larvae is strongly reduced.
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Gasperotti A, Göing S, Fajardo-Ruiz E, Forné I, Jung K. Function and Regulation of the Pyruvate Transporter CstA in Escherichia coli. Int J Mol Sci 2020; 21:ijms21239068. [PMID: 33260635 PMCID: PMC7730263 DOI: 10.3390/ijms21239068] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 11/20/2020] [Accepted: 11/23/2020] [Indexed: 12/02/2022] Open
Abstract
Pyruvate is a central metabolite that connects many metabolic pathways in living organisms. To meet the cellular pyruvate requirements, the enterobacterium Escherichia coli has at least three pyruvate uptake systems—the H+/pyruvate symporter BtsT, and two thus far less well-characterized transporters, YhjX and CstA. BtsT and CstA belong to the putative carbon starvation (CstA) family (transporter classification TC# 2.A.114). We have created an E. coli mutant that cannot grow on pyruvate as the sole carbon source and used it to characterize CstA as a pyruvate transporter. Transport studies in intact cells confirmed that CstA is a highly specific pyruvate transporter with moderate affinity and is energized by a proton gradient. When cells of a reporter strain were cultured in complex medium, cstA expression was maximal only in stationary phase. A DNA affinity-capture assay combined with mass spectrometry and an in-vivo reporter assay identified Fis as a repressor of cstA expression, in addition to the known activator cAMP-CRP. The functional characterization and regulation of this second pyruvate uptake system provides valuable information for understanding the complexity of pyruvate sensing and uptake in E. coli.
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Affiliation(s)
- Ana Gasperotti
- Department of Microbiology, Ludwig-Maximilians-Universität München, 82152 Martinsried, Germany; (A.G.); (S.G.); (E.F.-R.)
| | - Stephanie Göing
- Department of Microbiology, Ludwig-Maximilians-Universität München, 82152 Martinsried, Germany; (A.G.); (S.G.); (E.F.-R.)
| | - Elena Fajardo-Ruiz
- Department of Microbiology, Ludwig-Maximilians-Universität München, 82152 Martinsried, Germany; (A.G.); (S.G.); (E.F.-R.)
| | - Ignasi Forné
- Protein Analysis Unit, BioMedical Center (BMC), Ludwig-Maximilians-Universität München, 82152 Martinsried, Germany;
| | - Kirsten Jung
- Department of Microbiology, Ludwig-Maximilians-Universität München, 82152 Martinsried, Germany; (A.G.); (S.G.); (E.F.-R.)
- Correspondence:
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Ogasawara H, Ishizuka T, Hotta S, Aoki M, Shimada T, Ishihama A. Novel regulators of the csgD gene encoding the master regulator of biofilm formation in Escherichia coli K-12. Microbiology (Reading) 2020; 166:880-890. [DOI: 10.1099/mic.0.000947] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Under stressful conditions,
Escherichia coli
forms biofilm for survival by sensing a variety of environmental conditions. CsgD, the master regulator of biofilm formation, controls cell aggregation by directly regulating the synthesis of Curli fimbriae. In agreement of its regulatory role, as many as 14 transcription factors (TFs) have so far been identified to participate in regulation of the csgD promoter, each monitoring a specific environmental condition or factor. In order to identify the whole set of TFs involved in this typical multi-factor promoter, we performed in this study ‘promoter-specific transcription-factor’ (PS-TF) screening in vitro using a set of 198 purified TFs (145 TFs with known functions and 53 hitherto uncharacterized TFs). A total of 48 TFs with strong binding to the csgD promoter probe were identified, including 35 known TFs and 13 uncharacterized TFs, referred to as Y-TFs. As an attempt to search for novel regulators, in this study we first analysed a total of seven Y-TFs, including YbiH, YdcI, YhjC, YiaJ, YiaU, YjgJ and YjiR. After analysis of curli fimbriae formation, LacZ-reporter assay, Northern-blot analysis and biofilm formation assay, we identified at least two novel regulators, repressor YiaJ (renamed PlaR) and activator YhjC (renamed RcdB), of the csgD promoter.
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Affiliation(s)
- Hiroshi Ogasawara
- Academic Assembly School of Humanities and Social Sciences Institute of Humanities, Shinshu University, Asahi 3-1-1, Matsumoto, 390–8621, Japan
- Research Center for Supports to Advanced Science, Division of Gene Research, Shinshu University, Ueda, Nagano 386-8567, Japan
| | - Toshiyuki Ishizuka
- Research Center for Supports to Advanced Science, Division of Gene Research, Shinshu University, Ueda, Nagano 386-8567, Japan
| | - Shuhei Hotta
- Research Center for Supports to Advanced Science, Division of Gene Research, Shinshu University, Ueda, Nagano 386-8567, Japan
| | - Michiko Aoki
- Research Center for Supports to Advanced Science, Division of Gene Research, Shinshu University, Ueda, Nagano 386-8567, Japan
| | - Tomohiro Shimada
- School of Agriculture, Meiji University, 1-1-1 Higashi Mita, Tama-ku, Kawasaki, Kanagawa 214–8571, Japan
| | - Akira Ishihama
- Research Center for Micro-Nano Technology, Hosei University, Koganei, Tokyo 184-8584, Japan
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