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Hopkins HA, Lopezguerra C, Lau MJ, Raymann K. Making a Pathogen? Evaluating the Impact of Protist Predation on the Evolution of Virulence in Serratia marcescens. Genome Biol Evol 2024; 16:evae149. [PMID: 38961701 PMCID: PMC11332436 DOI: 10.1093/gbe/evae149] [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: 05/20/2024] [Revised: 06/25/2024] [Accepted: 06/30/2024] [Indexed: 07/05/2024] Open
Abstract
Opportunistic pathogens are environmental microbes that are generally harmless and only occasionally cause disease. Unlike obligate pathogens, the growth and survival of opportunistic pathogens do not rely on host infection or transmission. Their versatile lifestyles make it challenging to decipher how and why virulence has evolved in opportunistic pathogens. The coincidental evolution hypothesis postulates that virulence results from exaptation or pleiotropy, i.e. traits evolved for adaptation to living in one environment that have a different function in another. In particular, adaptation to avoid or survive protist predation has been suggested to contribute to the evolution of bacterial virulence (the training ground hypothesis). Here, we used experimental evolution to determine how the selective pressure imposed by a protist predator impacts the virulence and fitness of a ubiquitous environmental opportunistic bacterial pathogen that has acquired multidrug resistance: Serratia marcescens. To this aim, we evolved S. marcescens in the presence or absence of generalist protist predator, Tetrahymena thermophila. After 60 d of evolution, we evaluated genotypic and phenotypic changes by comparing evolved S. marcescens with the ancestral strain. Whole-genome shotgun sequencing of the entire evolved populations and individual isolates revealed numerous cases of parallel evolution, many more than statistically expected by chance, in genes associated with virulence. Our phenotypic assays suggested that evolution in the presence of a predator maintained virulence, whereas evolution in the absence of a predator resulted in attenuated virulence. We also found a significant correlation between virulence, biofilm formation, growth, and grazing resistance. Overall, our results provide evidence that bacterial virulence and virulence-related traits are maintained by selective pressures imposed by protist predation.
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Affiliation(s)
- Heather A Hopkins
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC, USA
- Department of Biology, University of North Carolina Greensboro, Greensboro, NC, USA
| | - Christian Lopezguerra
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC, USA
- Department of Biology, University of North Carolina Greensboro, Greensboro, NC, USA
| | - Meng-Jia Lau
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC, USA
| | - Kasie Raymann
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC, USA
- Department of Biology, University of North Carolina Greensboro, Greensboro, NC, USA
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Yu Q, Li H, Du L, Shen L, Zhang J, Yuan L, Yao H, Xiao H, Bai Q, Jia Y, Qiu J, Li Y. Transcriptional regulation of the yersiniabactin receptor fyuA gene by the ferric uptake regulator in Klebsiella pneumoniae NTUH-K2044. J Basic Microbiol 2024; 64:e2400001. [PMID: 38679904 DOI: 10.1002/jobm.202400001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 04/08/2024] [Accepted: 04/10/2024] [Indexed: 05/01/2024]
Abstract
The ferric uptake regulator (Fur) is a global regulator that influences the expression of virulence genes in Klebsiella pneumoniae. Bioinformatics analysis suggests Fur may involve in iron acquisition via the identified regulatory box upstream of the yersiniabactin receptor gene fyuA. To observe the impact of the gene fyuA on the virulence of K. pneumoniae, the gene fyuA knockout strain and complementation strain were constructed and then conducted a series of phenotypic experiments including chrome azurol S (CAS) detection, crystal violet staining, and wax moth virulence experiment. To examine the regulatory relationship between Fur and the gene fyuA, green fluorescent protein (GFP) reporter gene fusion assay, real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR), gel migration assay (EMSA), and DNase I footprinting assay were used to clarify the regulatory mechanism of Fur on fyuA. CAS detection revealed that the gene fyuA could affect the generation of iron carriers in K. pneumoniae. Crystal violet staining experiment showed that fyuA could positively influence biofilm formation. Wax moth virulence experiment indicated that the deletion of the fyuA could weaken bacterial virulence. GFP reporter gene fusion experiment and RT-qPCR analysis revealed that Fur negatively regulated the expression of fyuA in iron-sufficient environment. EMSA experiment demonstrated that Fur could directly bind to the promoter region of fyuA, and DNase I footprinting assay further identified the specific binding site sequences. The study showed that Fur negatively regulated the transcriptional expression of fyuA by binding to upstream of the gene promoter region, and then affected the virulence of K. pneumoniae.
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Affiliation(s)
- Qian Yu
- School of Public Health, Chongqing Medical University, Chongqing, China
| | - Hailin Li
- School of Public Health, Chongqing Medical University, Chongqing, China
| | - Ling Du
- Chengdu Center for Disease Control and Prevention, Chengdu, Sichuan, China
| | - Lifei Shen
- Jiangbei District Center for Disease Control and Prevention, Jiangbei, Chongqing, China
| | - Jiaxue Zhang
- Jiangbei District Center for Disease Control and Prevention, Jiangbei, Chongqing, China
| | - Lingyue Yuan
- Shanghai Center for Disease Control and Prevention, Shanghai, China
| | - Huang Yao
- School of Public Health, Chongqing Medical University, Chongqing, China
| | - Hong Xiao
- School of Public Health, Chongqing Medical University, Chongqing, China
| | - Qunhua Bai
- School of Public Health, Chongqing Medical University, Chongqing, China
| | - Yan Jia
- School of Public Health, Chongqing Medical University, Chongqing, China
| | - Jingfu Qiu
- School of Public Health, Chongqing Medical University, Chongqing, China
| | - Yingli Li
- School of Public Health, Chongqing Medical University, Chongqing, China
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3
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Li Y, Ni M. Regulation of biofilm formation in Klebsiella pneumoniae. Front Microbiol 2023; 14:1238482. [PMID: 37744914 PMCID: PMC10513181 DOI: 10.3389/fmicb.2023.1238482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2023] [Accepted: 08/23/2023] [Indexed: 09/26/2023] Open
Abstract
Klebsiella pneumoniae is an important Gram-negative opportunistic pathogen that is responsible for a variety of nosocomial and community-acquired infections. Klebsiella pneumoniae has become a major public health issue owing to the rapid global spread of extensively-drug resistant (XDR) and hypervirulent strains. Biofilm formation is an important virulence trait of K. pneumoniae. A biofilm is an aggregate of microorganisms attached to an inert or living surface by a self-produced exo-polymeric matrix that includes proteins, polysaccharides and extracellular DNA. Bacteria within the biofilm are shielded from antibiotics treatments and host immune responses, making it more difficult to eradicate K. pneumoniae-induced infection. However, the detailed mechanisms of biofilm formation in K. pneumoniae are still not clear. Here, we review the factors involved in the biofilm formation of K. pneumoniae, which might provide new clues to address this clinical challenge.
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Affiliation(s)
| | - Ming Ni
- Department and Institute of Infectious Disease, Tongji Hospital, Tongji Medical College and State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Disease, Huazhong University of Science and Technology, Wuhan, China
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4
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Jati AP, Sola-Campoy PJ, Bosch T, Schouls LM, Hendrickx APA, Bautista V, Lara N, Raangs E, Aracil B, Rossen JWA, Friedrich AW, Navarro Riaza AM, Cañada-García JE, Ramírez de Arellano E, Oteo-Iglesias J, Pérez-Vázquez M, García-Cobos S. Widespread Detection of Yersiniabactin Gene Cluster and Its Encoding Integrative Conjugative Elements (ICE Kp) among Nonoutbreak OXA-48-Producing Klebsiella pneumoniae Clinical Isolates from Spain and the Netherlands. Microbiol Spectr 2023; 11:e0471622. [PMID: 37310221 PMCID: PMC10434048 DOI: 10.1128/spectrum.04716-22] [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: 11/18/2022] [Accepted: 05/22/2023] [Indexed: 06/14/2023] Open
Abstract
In this study, we determined the presence of virulence factors in nonoutbreak, high-risk clones and other isolates belonging to less common sequence types associated with the spread of OXA-48-producing Klebsiella pneumoniae clinical isolates from The Netherlands (n = 61) and Spain (n = 53). Most isolates shared a chromosomally encoded core of virulence factors, including the enterobactin gene cluster, fimbrial fim and mrk gene clusters, and urea metabolism genes (ureAD). We observed a high diversity of K-Locus and K/O loci combinations, KL17 and KL24 (both 16%), and the O1/O2v1 locus (51%) being the most prevalent in our study. The most prevalent accessory virulence factor was the yersiniabactin gene cluster (66.7%). We found seven yersiniabactin lineages-ybt 9, ybt 10, ybt 13, ybt 14, ybt 16, ybt 17, and ybt 27-which were chromosomally embedded in seven integrative conjugative elements (ICEKp): ICEKp3, ICEKp4, ICEKp2, ICEKp5, ICEKp12, ICEKp10, and ICEKp22, respectively. Multidrug-resistant lineages-ST11, ST101, and ST405-were associated with ybt 10/ICEKp4, ybt 9/ICEKp3, and ybt 27/ICEKp22, respectively. The fimbrial adhesin kpi operon (kpiABCDEFG) was predominant among ST14, ST15, and ST405 isolates, as well as the ferric uptake system kfuABC, which was also predominant among ST101 isolates. No convergence of hypervirulence and resistance was observed in this collection of OXA-48-producing K. pneumoniae clinical isolates. Nevertheless, two isolates, ST133 and ST792, were positive for the genotoxin colibactin gene cluster (ICEKp10). In this study, the integrative conjugative element, ICEKp, was the major vehicle for yersiniabactin and colibactin gene clusters spreading. IMPORTANCE Convergence of multidrug resistance and hypervirulence in Klebsiella pneumoniae isolates has been reported mostly related to sporadic cases or small outbreaks. Nevertheless, little is known about the real prevalence of carbapenem-resistant hypervirulent K. pneumoniae since these two phenomena are often separately studied. In this study, we gathered information on the virulent content of nonoutbreak, high-risk clones (i.e., ST11, ST15, and ST405) and other less common STs associated with the spread of OXA-48-producing K. pneumoniae clinical isolates. The study of virulence content in nonoutbreak isolates can help us to expand information on the genomic landscape of virulence factors in K. pneumoniae population by identifying virulence markers and their mechanisms of spread. Surveillance should focus not only on antimicrobial resistance but also on virulence characteristics to avoid the spread of multidrug and (hyper)virulent K. pneumoniae that may cause untreatable and more severe infections.
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Affiliation(s)
- Afif P. Jati
- University of Groningen, University Medical Center Groningen, Department of Medical Microbiology and Infection Prevention, Groningen, The Netherlands
- Indonesian Society of Bioinformatics and Biodiversity, Indonesia
| | - Pedro J. Sola-Campoy
- Laboratorio de Referencia e Investigación en Resistencia a Antibióticos e Infecciones Relacionadas con la Asistencia Sanitaria, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - Thijs Bosch
- Infectious Diseases Research, Diagnostics and Laboratory Surveillance, Centre for Infectious Disease Control Netherlands, National Institute for Public Health and the Environment, Bilthoven, The Netherlands
| | - Leo M. Schouls
- Infectious Diseases Research, Diagnostics and Laboratory Surveillance, Centre for Infectious Disease Control Netherlands, National Institute for Public Health and the Environment, Bilthoven, The Netherlands
| | - Antoni P. A. Hendrickx
- Infectious Diseases Research, Diagnostics and Laboratory Surveillance, Centre for Infectious Disease Control Netherlands, National Institute for Public Health and the Environment, Bilthoven, The Netherlands
| | - Verónica Bautista
- Laboratorio de Referencia e Investigación en Resistencia a Antibióticos e Infecciones Relacionadas con la Asistencia Sanitaria, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - Noelia Lara
- Laboratorio de Referencia e Investigación en Resistencia a Antibióticos e Infecciones Relacionadas con la Asistencia Sanitaria, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - Erwin Raangs
- University of Groningen, University Medical Center Groningen, Department of Medical Microbiology and Infection Prevention, Groningen, The Netherlands
| | - Belén Aracil
- Laboratorio de Referencia e Investigación en Resistencia a Antibióticos e Infecciones Relacionadas con la Asistencia Sanitaria, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
- CIBER de Enfermedades Infecciosas, Spanish Network for Research in Infectious Diseases, Instituto de Salud Carlos III, Madrid, Spain
| | - John W. A. Rossen
- University of Groningen, University Medical Center Groningen, Department of Medical Microbiology and Infection Prevention, Groningen, The Netherlands
- Laboratory of Medical Microbiology and Infectious Diseases, Isala Hospital, Zwolle, The Netherlands
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, Utah, USA
| | - Alex W. Friedrich
- University of Groningen, University Medical Center Groningen, Department of Medical Microbiology and Infection Prevention, Groningen, The Netherlands
- University Hospital Münster, Institute of European Prevention Networks in Infection Control, Münster, Germany
| | - Ana M. Navarro Riaza
- Laboratorio de Referencia e Investigación en Resistencia a Antibióticos e Infecciones Relacionadas con la Asistencia Sanitaria, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - Javier E. Cañada-García
- Laboratorio de Referencia e Investigación en Resistencia a Antibióticos e Infecciones Relacionadas con la Asistencia Sanitaria, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - Eva Ramírez de Arellano
- Laboratorio de Referencia e Investigación en Resistencia a Antibióticos e Infecciones Relacionadas con la Asistencia Sanitaria, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
- CIBER de Enfermedades Infecciosas, Spanish Network for Research in Infectious Diseases, Instituto de Salud Carlos III, Madrid, Spain
| | - Jesús Oteo-Iglesias
- Laboratorio de Referencia e Investigación en Resistencia a Antibióticos e Infecciones Relacionadas con la Asistencia Sanitaria, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
- CIBER de Enfermedades Infecciosas, Spanish Network for Research in Infectious Diseases, Instituto de Salud Carlos III, Madrid, Spain
| | - María Pérez-Vázquez
- Laboratorio de Referencia e Investigación en Resistencia a Antibióticos e Infecciones Relacionadas con la Asistencia Sanitaria, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
- CIBER de Enfermedades Infecciosas, Spanish Network for Research in Infectious Diseases, Instituto de Salud Carlos III, Madrid, Spain
| | - Silvia García-Cobos
- University of Groningen, University Medical Center Groningen, Department of Medical Microbiology and Infection Prevention, Groningen, The Netherlands
- Laboratorio de Referencia e Investigación en Resistencia a Antibióticos e Infecciones Relacionadas con la Asistencia Sanitaria, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - The Dutch and Spanish Collaborative Working Groups on Surveillance on Carbapenemase-Producing Enterobacterales
- University of Groningen, University Medical Center Groningen, Department of Medical Microbiology and Infection Prevention, Groningen, The Netherlands
- Indonesian Society of Bioinformatics and Biodiversity, Indonesia
- Laboratorio de Referencia e Investigación en Resistencia a Antibióticos e Infecciones Relacionadas con la Asistencia Sanitaria, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
- Infectious Diseases Research, Diagnostics and Laboratory Surveillance, Centre for Infectious Disease Control Netherlands, National Institute for Public Health and the Environment, Bilthoven, The Netherlands
- CIBER de Enfermedades Infecciosas, Spanish Network for Research in Infectious Diseases, Instituto de Salud Carlos III, Madrid, Spain
- Laboratory of Medical Microbiology and Infectious Diseases, Isala Hospital, Zwolle, The Netherlands
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, Utah, USA
- University Hospital Münster, Institute of European Prevention Networks in Infection Control, Münster, Germany
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5
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Wang Y, Jin Y, Sun F, Zhang Y, Liu Q, Wang Q, Yang D, Zhang Y. The c-di-GMP signalling component YfiR regulates multiple bacterial phenotypes and virulence in Pseudomonas plecoglossicida. J Appl Microbiol 2023; 134:lxad157. [PMID: 37500265 DOI: 10.1093/jambio/lxad157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 07/12/2023] [Accepted: 07/26/2023] [Indexed: 07/29/2023]
Abstract
AIMS Pseudomonas plecoglossicida (P. plecoglossicida) is the causative agent of visceral granulomas disease in large yellow croaker (Larimichthys crocea) and it causes severe economic loss to its industry. Biofilm formation, related to intracellular cyclic bis (3'-5') diguanylic acid (c-di-GMP) levels, is essential for the lifestyle of P. plecoglossicida. This research aims to investigate the role of YfiR-a key regulator of the diguanylate cyclase YfiN to regulate c-di-GMP levels and reveal its regulatory function of bacterial virulence expression in P. plecoglossicida. METHODS AND RESULTS A genetic analysis was carried out to identify the yfiBNR operon for c-di-GMP regulation in P. plecoglossicida. Then, we constructed a yfiR mutant and observed increased c-di-GMP levels, enhanced biofilm formation, increased exopolysaccharides, and diminished swimming and swarming motility in this strain. Moreover, through establishing a yolk sac microinjection infection model in zebrafish larvae, an attenuated phenotype of yfiR mutant that manifested as restored survival and lower bacterial colonization was found. CONCLUSIONS YfiR is the key regulator of virulence in P. plecoglossicida, which contributes to c-di-GMP level, biofilm formation, exopolysaccharides production, swimming, swarming motility, and bacterial colonization in zebrafish model.
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Affiliation(s)
- Ying Wang
- State Key Laboratory of Bioreactor Engineering, Laboratory for Aquatic Animal Diseases, East China University of Science and Technology, Shanghai 200237, China
| | - Yinhua Jin
- State Key Laboratory of Bioreactor Engineering, Laboratory for Aquatic Animal Diseases, East China University of Science and Technology, Shanghai 200237, China
| | - Fei Sun
- State Key Laboratory of Bioreactor Engineering, Laboratory for Aquatic Animal Diseases, East China University of Science and Technology, Shanghai 200237, China
| | - Yuanxing Zhang
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519000, China
- Shanghai Engineering Research Center of Maricultured Animal Vaccines, Shanghai 200237, China
| | - Qin Liu
- State Key Laboratory of Bioreactor Engineering, Laboratory for Aquatic Animal Diseases, East China University of Science and Technology, Shanghai 200237, China
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519000, China
- Shanghai Engineering Research Center of Maricultured Animal Vaccines, Shanghai 200237, China
| | - Qiyao Wang
- State Key Laboratory of Bioreactor Engineering, Laboratory for Aquatic Animal Diseases, East China University of Science and Technology, Shanghai 200237, China
- Shanghai Engineering Research Center of Maricultured Animal Vaccines, Shanghai 200237, China
| | - Dahai Yang
- State Key Laboratory of Bioreactor Engineering, Laboratory for Aquatic Animal Diseases, East China University of Science and Technology, Shanghai 200237, China
- Shanghai Engineering Research Center of Maricultured Animal Vaccines, Shanghai 200237, China
| | - Yibei Zhang
- State Key Laboratory of Bioreactor Engineering, Laboratory for Aquatic Animal Diseases, East China University of Science and Technology, Shanghai 200237, China
- Shanghai Engineering Research Center of Maricultured Animal Vaccines, Shanghai 200237, China
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6
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Cifuentes EA, Sierra MA, Yepes AF, Baldión AM, Rojas JA, Álvarez-Moreno CA, Anzola JM, Zambrano MM, Huertas MG. Endotracheal tube microbiome in hospitalized patients defined largely by hospital environment. Respir Res 2022; 23:168. [PMID: 35751068 PMCID: PMC9233342 DOI: 10.1186/s12931-022-02086-7] [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: 11/08/2021] [Accepted: 06/13/2022] [Indexed: 11/16/2022] Open
Abstract
Background Studies of the respiratory tract microbiome primarily focus on airway and lung microbial diversity, but it is still unclear how these microbial communities may be affected by intubation and long periods in intensive care units (ICU), an aspect that today could aid in the understanding of COVID19 progression and disease severity. This study aimed to explore and characterize the endotracheal tube (ETT) microbiome by analyzing ETT-associated microbial communities. Methods This descriptive study was carried out on adult patients subjected to invasive mechanical ventilation from 2 to 21 days. ETT samples were obtained from 115 patients from ICU units in two hospitals. Bacteria isolated from endotracheal tubes belonging to the ESKAPE group were analyzed for biofilm formation using crystal violet quantification. Microbial profiles were obtained using Illumina sequencing of 16S rRNA gene. Results The ETT microbiome was mainly composed by the phyla Proteobacteria, Firmicutes and Bacteroidetes. Microbiome composition correlated with the ICU in which patients were hospitalized, while intubation time and diagnosis of ventilator-associated pneumonia (VAP) did not show any significant association. Conclusion These results suggest that the ICU environment, or medical practices, could be a key to microbial colonization and have a direct influence on the ETT microbiomes of patients that require mechanical ventilation. Supplementary Information The online version contains supplementary material available at 10.1186/s12931-022-02086-7.
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Affiliation(s)
| | - Maria A Sierra
- Corporación CorpoGen Research Center, Bogotá, Colombia.,Tri-Institutional Computational Biology & Medicine Program, Weill Cornell Medicine, New York, NY, USA
| | | | | | | | | | - Juan Manuel Anzola
- Corporación CorpoGen Research Center, Bogotá, Colombia.,Universidad Central, Bogotá, Colombia
| | - María Mercedes Zambrano
- Corporación CorpoGen Research Center, Bogotá, Colombia.,Universidad Central, Bogotá, Colombia
| | - Monica G Huertas
- Corporación CorpoGen Research Center, Bogotá, Colombia. .,Universidad Pedagógica y Tecnológica de Colombia, Tunja, Boyacá, Colombia.
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7
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Shen L, Zhang J, Xue J, Du L, Yuan L, Nie H, Dai S, Yu Q, Li Y. Regulation of ECP fimbriae-related genes by the transcriptional regulator RcsAB in Klebsiella pneumoniae NTUH-K2044. J Basic Microbiol 2022; 62:593-603. [PMID: 35132658 DOI: 10.1002/jobm.202100595] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Revised: 01/06/2022] [Accepted: 01/15/2022] [Indexed: 11/11/2022]
Abstract
Klebsiella pneumoniae is one of the major pathogens causing nosocomial infections. The regulator of capsule synthesis (Rcs) system is a complex signal transduction pathway that is involved in the regulation of virulence factors of K. pneumoniae as an important transcriptional regulator. The RcsAB box-like sequence was found to be present in the promoter-proximal regions of ykgK, one of the ECP fimbriae-related genes, which suggested the expression of ECP fimbriae may be regulated by RcsAB. The ykgK gene in K. pneumoniae has 86% similarity to the ecpR gene in Escherichia coli. Nucleotide sequence alignment revealed a similar ECP fimbriae gene cluster including six genes in K. pneumoniae, which was proved to be on the same operon in this study. The electrophoretic mobility shift assay and DNase I assay, relative fluorescence expression, β-galactosidase activity, and relative gene expression of ykgK in the wild-type and mutant strains were performed to determine the transcriptional regulation mechanism of RcsAB on ECP fimbriae. The mutant ΔykgK and complementary strain ΔykgK/cΔykgK were constructed to complete the Galleria mellonella larvae infection experiment and biofilm formation assay. This study showed that RcsAB binds directly to the promoter region of the ykgK gene to positively regulate ECP fimbriae-related gene clusters, and then positively affect the biofilm formation.
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Affiliation(s)
- Lifei Shen
- School of Public Health and Management, Chongqing Medical University, Chongqing, China
| | - Jiaxue Zhang
- Chongqing Jiangbei District Center for Disease Control and Prevention, Chongqing, China
| | - Jian Xue
- Zunyi Medical and Pharmaceutical College, Zunyi, China
| | - Ling Du
- School of Public Health and Management, Chongqing Medical University, Chongqing, China
| | - Lingyue Yuan
- School of Public Health and Management, Chongqing Medical University, Chongqing, China
| | - Hao Nie
- School of Public Health and Management, Chongqing Medical University, Chongqing, China
| | - Sue Dai
- School of Public Health and Management, Chongqing Medical University, Chongqing, China
| | - Qian Yu
- School of Public Health and Management, Chongqing Medical University, Chongqing, China
| | - Yingli Li
- School of Public Health and Management, Chongqing Medical University, Chongqing, China
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8
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Wang HY, Chen XC, Yan ZH, Tu F, He T, Gopinath SCB, Rui XH, Cao FT. Human neutrophil peptide 1 promotes immune sterilization in vivo by reducing the virulence of multidrug-resistant Klebsiella pneumoniae and increasing the ability of macrophages. Biotechnol Appl Biochem 2021; 69:2091-2101. [PMID: 34664729 DOI: 10.1002/bab.2270] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 10/04/2021] [Indexed: 12/24/2022]
Abstract
By studying the expression in patients and cell modeling in vitro, antimicrobial peptides for Klebsiella were screened. Killing curve and membrane permeability experiments are used to study the antibacterial effect of antimicrobial peptides in vitro. Cytotoxicity-related indicators including lipopolysaccharide (LPS), capsule polysaccharide (CPS), and outer membrane protein expression were measured. Intranasal inoculation of pneumoconiosis was used to construct a mouse infection model, and the survival rate and cytokine expression level were tested. Human neutrophil peptide 1 (HNP-1) showed a significant antibacterial effect, which improved the permeability of the outer membrane of K. pneumoniae. Moreover, HNP-1 decreased LPS, CPS content, and outer membrane proteins. K. pneumoniae infection decreased antimicrobial peptide, oxidative stress, and autophagy-related genes, while HNP-1 increased these genes. After coculture with macrophages, the endocytosis of macrophages is enhanced and the bacterial load is greater in the K. pneumoniae + peptide group. Besides, higher levels of pp38 and pp65 in the K. pneumoniae + peptide group. HNP-1 rescued the cytotoxicity induced by K. pneumoniae. The survival rate is significantly improved after K. pneumoniae is treated by HNP-1. All cytokines in the peptide group were significantly higher. HNP-1 promotes immune sterilization by reducing the virulence of multidrug-resistant K. pneumoniae and increasing the ability of macrophages.
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Affiliation(s)
- Hui-Yun Wang
- Department of Laboratory Medicine, Jiangyin Traditional Hospital, Wuxi 214005, China
| | - Xiao-Chun Chen
- Department of Laboratory Medicine, Taizhou Second People's Hospital, Jiangyan District, Taizhou City, China
| | - Zhi-Han Yan
- Hepatology Department, Wuxi Fifth People's Hospital, Wuxi, China
| | - Fan Tu
- Department of Laboratory Medicine, Wuxi Fifth People's Hospital, Wuxi, China
| | - Tian He
- Department of Laboratory Medicine, Wuxi Fifth People's Hospital, Wuxi, China
| | - Subash C B Gopinath
- Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, Perlis, Malaysia.,Faculty of Chemical Engineering Technology, Universiti Malaysia Perlis, Perlis, Malaysia
| | - Xiao-Hong Rui
- Department of Laboratory Medicine, Wuxi Fifth People's Hospital, Wuxi, China
| | - Fu-Tao Cao
- Emergency Department, Wuxi Second People's Hospital, Wuxi, China
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9
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Bioprocess development for enhanced endoglucanase production by newly isolated bacteria, purification, characterization and in-vitro efficacy as anti-biofilm of Pseudomonas aeruginosa. Sci Rep 2021; 11:9754. [PMID: 33963217 PMCID: PMC8105381 DOI: 10.1038/s41598-021-87901-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 04/06/2021] [Indexed: 02/03/2023] Open
Abstract
Endoglucanase producing bacteria were isolated from Egyptian soils and the most active bacterial strain was identified as Bacillus subtilis strain Fatma/1. Plackett-Burman statistical design was carried out to assess the effect of seven process variables on endoglucanase production. Carboxymethyl cellulose (CMC), yeast extract and peptone were the most significant variables that enhanced the endoglucanase production and thus were selected for further optimization using face-centered central composite design. The highest yield of endoglucanase (32.37 U/mL) was obtained in run no. 9, using 18 g/L CMC, 8 g/L peptone, 7 g/L yeast extract and 0.1 g/L FeSO4.7H2O. The optimized medium showed about eightfold increase in endoglucanase production compared to the unoptimized medium. The produced crude enzyme was further purified by ammonium sulfate precipitation, then DEAE-Sepharose CL6B column. The purified enzyme was shown to have a molecular weight of 37 kDa. The enzyme showed maximum activity at pH 8.0, temperature of 50 °C, incubation time of 60 min. The half-life time (T1/2) was 139.53 min at 50 °C, while being 82.67 min at 60 °C. Endoglucanase at concentration of 12 U/mL effectively removed 84.61% of biofilm matrix of Pseudomonas aeruginosa with marked reduction in carbohydrate content of the biofilm from 63.4 to 7.9 μg.
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Guo X, Yuan J, Song X, Wang X, Sun Q, Tian J, Li X, Ding M, Liu Y. Bacteria metabolites from Peganum harmala L. polysaccharides inhibits polyQ aggregation through proteasome-mediated protein degradation in C. elegans. Int J Biol Macromol 2020; 161:681-691. [PMID: 32544588 DOI: 10.1016/j.ijbiomac.2020.06.091] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 05/30/2020] [Accepted: 06/10/2020] [Indexed: 12/31/2022]
Abstract
Huntington's disease (HD) is a relentlessly progressive neurodegenerative disease featured by the over-expanded polyglutamine (polyQ)-induced protein aggregation. Using Caenorhabditis elegans (C. elegans) as a model system, we show that water soluble polysaccharide extracted from the herb Peganum harmala L. (PS1) not only reduces polyQ aggregation but also alleviates the associated neurotoxicity. Genetic and pharmacologic analysis suggested that PS1 treatment acts though proteasome-mediated protein degradation pathway to inhibit polyQ aggregation. Notably, the efficacy of PS1 is aroused specifically by co-incubation with live Escherichia coli OP50, which is the sole food source for worms. Further UPLC-Q-TOF/MS analysis determined the bioactivity of polyQ inhibition, which is composed of several oligosaccharides, including stachyoses, verbascoses, trisaccharides and tetrasaccharides composed of galacturonic acids. Together, our study revealed a potential drug target for further HD treatment and pinpointed the possibility that the secreted metabolites produced from bacteria treated with various compounds may provide direct beneficial effect to human bodies.
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Affiliation(s)
- Xiaoyu Guo
- Beijing University of Chinese Medicine, Beijing 102488, China
| | - Jiang Yuan
- Beijing University of Chinese Medicine, Beijing 102488, China
| | - Xingzhuo Song
- Beijing University of Chinese Medicine, Beijing 102488, China
| | - Xirui Wang
- Beijing University of Chinese Medicine, Beijing 102488, China
| | - Qianqian Sun
- Beijing University of Chinese Medicine, Beijing 102488, China
| | - Jingyun Tian
- Beijing University of Chinese Medicine, Beijing 102488, China
| | - Xia Li
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.
| | - Mei Ding
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.
| | - Yonggang Liu
- Beijing University of Chinese Medicine, Beijing 102488, China.
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11
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Peng D, Li X, Liu P, Zhou X, Luo M, Su K, Chen S, Zhang Z, He Q, Qiu J, Li Y. Transcriptional regulation of galF by RcsAB affects capsular polysaccharide formation in Klebsiella pneumoniae NTUH-K2044. Microbiol Res 2018; 216:70-78. [PMID: 30269858 DOI: 10.1016/j.micres.2018.08.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 08/22/2018] [Accepted: 08/23/2018] [Indexed: 01/17/2023]
Abstract
RcsAB is an atypical two-component regulatory system that can regulate exopolysaccharide biosynthesis and is involved in the virulence of K. pneumoniae. The gene galF is well known as a gene involved in the biosynthesis of capsular polysaccharide (CPS). The specific DNA identification sequence for transcriptional regulation of RcsAB was found to be present in the promoter region of galF. This study aimed to detect the function of RcsAB in virulence and in biofilm and CPS formation. In addition, the transcriptional regulation of the galF gene in K. pneumoniae was studied. To determine the function of rcsAB gene, the wild-type K. pneumoniae strain NTUH-K2044 and the rcsAB knockout and complemented strains were used. The results showed decreased virulence, biofilm formation, and CPS levels in the rcsAB knockout strain. Complementation of the knockout by introducing an rcsAB fragment on an expression plasmid partially restored the virulence, biofilm, and CPS functions of the knockout strain. It indicated that the rcsAB genes might affect CPS formation and virulence of K. pneumonia. RT-qPCR, EMSA and DNase I footprinting assays were conducted to identify the transcriptional regulation of galF by RcsAB. RcsAB was seen to bind to the galF promoter-proximal region, and the binding site was further identified to be located from -177 bp to -152 bp upstream of the galF promoter. In conclusion, RcsAB could regulate the transcription of the galF gene positively by binding to the galF promoter DNA directly, and then affects the CPS formation of K. pneumonia.
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Affiliation(s)
- Dan Peng
- School of Public Health and Management, Chongqing Medical University, Chongqing, China
| | - Xuan Li
- School of Public Health and Management, Chongqing Medical University, Chongqing, China
| | - Pin Liu
- School of Public Health and Management, Chongqing Medical University, Chongqing, China
| | - Xipeng Zhou
- Chongqing Tuberculosis Control Institute, Chongqing, China
| | - Mei Luo
- School of Public Health and Management, Chongqing Medical University, Chongqing, China
| | - Kewen Su
- School of Public Health and Management, Chongqing Medical University, Chongqing, China
| | - Shuai Chen
- School of Public Health and Management, Chongqing Medical University, Chongqing, China
| | - Zhongshuang Zhang
- School of Public Health and Management, Chongqing Medical University, Chongqing, China
| | - Qiang He
- School of Public Health and Management, Chongqing Medical University, Chongqing, China
| | - Jingfu Qiu
- School of Public Health and Management, Chongqing Medical University, Chongqing, China
| | - Yingli Li
- School of Public Health and Management, Chongqing Medical University, Chongqing, China.
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Wang H, Li W, Gu L, Gao X, Ni B, Deng H, Yang R, Han Y. Emergence of two distinct subpopulations from Klebsiella pneumoniae grown in the stimulated microgravity environment. Future Microbiol 2017; 12:939-951. [DOI: 10.2217/fmb-2017-0032] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Aim: To isolate and characterize the two phenotypically distinct subpopulations from Klebsiella pneumoniae clonal cultures grown in the simulate microgravity environment. Materials & methods: Here clonal culture of K. pneumoniae strain ATCC BAA-1705 was grown within a vertically rotating wall vessel bioreactor. Microscopic, colony staining, biofilm assays and quantitative proteomics were used to define the features of subpopulations. Results: Two subpopulations were isolated based on colony appearance and bacterial morphology and indicated the different capability of biofilm formation and antibiotics resistance. Conclusion: These findings would raise a possibility of understanding the adaptive roles of bacterial subpopulations formed under certain conditions from the viewpoint of population variation.
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Affiliation(s)
- Haili Wang
- State Key Laboratory of Pathogen & Biosecurity, Beijing Institute of Microbiology & Epidemiology, Beijing 100071, China
| | - Wenliang Li
- State Key Laboratory of Pathogen & Biosecurity, Beijing Institute of Microbiology & Epidemiology, Beijing 100071, China
- School of Medicine, Jiangsu University, Zhenjiang 212013, Jiangsu, China
| | - Lixiao Gu
- MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Xiaofang Gao
- State Key Laboratory of Pathogen & Biosecurity, Beijing Institute of Microbiology & Epidemiology, Beijing 100071, China
| | - Bin Ni
- School of Medicine, Jiangsu University, Zhenjiang 212013, Jiangsu, China
| | - Haiteng Deng
- MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Ruifu Yang
- State Key Laboratory of Pathogen & Biosecurity, Beijing Institute of Microbiology & Epidemiology, Beijing 100071, China
| | - Yanping Han
- State Key Laboratory of Pathogen & Biosecurity, Beijing Institute of Microbiology & Epidemiology, Beijing 100071, China
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13
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Wang H, Yan Y, Rong D, Wang J, Wang H, Liu Z, Wang J, Yang R, Han Y. Increased biofilm formation ability in Klebsiella pneumoniae after short-term exposure to a simulated microgravity environment. Microbiologyopen 2016; 5:793-801. [PMID: 27185296 PMCID: PMC5061716 DOI: 10.1002/mbo3.370] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2016] [Revised: 03/17/2016] [Accepted: 03/29/2016] [Indexed: 01/11/2023] Open
Abstract
Biofilm formation is closely related to the pathogenetic processes of Klebsiella pneumoniae, which frequently causes infections in immunocompromised individuals. The immune system of astronauts is compromised in spaceflight. Accordingly, K. pneumoniae, which used to be isolated from orbiting spacecraft and astronauts, poses potential threats to the health of astronauts and mission security. Microgravity is a key environmental cue during spaceflight. Therefore, determining its effects on bacterial biofilm formation is necessary. In this study, K. pneumoniae ATCC BAA-1705 was exposed to a simulated microgravity (SMG) environment. K. pneumoniae grown under SMG formed thicker biofilms compared with those under normal gravity (NG) control after 2 weeks of subculture. Two indicative dyes (i.e., Congo red and calcofluor) specifically binding to cellulose fibers and/or fimbriae were utilized to reconfirm the enhanced biofilm formation ability of K. pneumoniae grown under SMG. Further analysis showed that the biofilms formed by SMG-treated K. pneumoniae were susceptible to cellulase digestion. Yeast cells mannose-resistant agglutination by K. pneumoniae type 3 fimbriae was more obvious in the SMG group, which suggests that cellulose production and type 3 fimbriae expression in K. pneumoniae were both enhanced under the SMG condition. Transcriptomic analysis showed that 171 genes belonging to 15 functional categories were dysregulated in this organism exposed to the SMG conditions compared with those in the NG group, where the genes responsible for the type 3 fimbriae (mrkABCDF) and its regulator (mrkH) were upregulated.
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Affiliation(s)
- Haili Wang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China
| | - Yanfeng Yan
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China
| | - Dan Rong
- Department of Medical Monitoring and Support, Astronaut Center of China, Beijing, 100094, China
| | - Jing Wang
- Animal Husbandry Base Teaching and Research Section, College of Animal Science and Technology, Hebei North University, Zhangjiakou, Hebei, 075131, China
| | - Hongduo Wang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China
| | - Zizhong Liu
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China
| | - Jiaping Wang
- Department of Medical Monitoring and Support, Astronaut Center of China, Beijing, 100094, China
| | - Ruifu Yang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China.
| | - Yanping Han
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China.
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Xu M, Yang X, Yang XA, Zhou L, Liu TZ, Fan Z, Jiang T. Structural insights into the regulatory mechanism of the Pseudomonas aeruginosa YfiBNR system. Protein Cell 2016; 7:403-16. [PMID: 27113583 PMCID: PMC4887326 DOI: 10.1007/s13238-016-0264-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 03/10/2016] [Indexed: 11/29/2022] Open
Abstract
YfiBNR is a recently identified bis-(3’-5’)-cyclic dimeric GMP (c-di-GMP) signaling system in opportunistic pathogens. It is a key regulator of biofilm formation, which is correlated with prolonged persistence of infection and antibiotic drug resistance. In response to cell stress, YfiB in the outer membrane can sequester the periplasmic protein YfiR, releasing its inhibition of YfiN on the inner membrane and thus provoking the diguanylate cyclase activity of YfiN to induce c-di-GMP production. However, the detailed regulatory mechanism remains elusive. Here, we report the crystal structures of YfiB alone and of an active mutant YfiBL43P complexed with YfiR with 2:2 stoichiometry. Structural analyses revealed that in contrast to the compact conformation of the dimeric YfiB alone, YfiBL43P adopts a stretched conformation allowing activated YfiB to penetrate the peptidoglycan (PG) layer and access YfiR. YfiBL43P shows a more compact PG-binding pocket and much higher PG binding affinity than wild-type YfiB, suggesting a tight correlation between PG binding and YfiB activation. In addition, our crystallographic analyses revealed that YfiR binds Vitamin B6 (VB6) or L-Trp at a YfiB-binding site and that both VB6 and L-Trp are able to reduce YfiBL43P-induced biofilm formation. Based on the structural and biochemical data, we propose an updated regulatory model of the YfiBNR system.
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Affiliation(s)
- Min Xu
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
| | - Xuan Yang
- Chinese Academy of Sciences Key Laboratory of Infection and Immunity, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
| | - Xiu-An Yang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
| | - Lei Zhou
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Tie-Zheng Liu
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zusen Fan
- Chinese Academy of Sciences Key Laboratory of Infection and Immunity, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Tao Jiang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China.
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15
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Yang X, Yang XA, Xu M, Zhou L, Fan Z, Jiang T. Crystal structures of YfiR from Pseudomonas aeruginosa in two redox states. Biochem Biophys Res Commun 2015; 461:14-20. [PMID: 25849887 DOI: 10.1016/j.bbrc.2015.03.160] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 03/28/2015] [Indexed: 10/23/2022]
Abstract
YfiBNR is a recently identified c-di-GMP regulatory system involved in bacterial biofilm formation. The periplasmic protein YfiR inhibits the diguanylate cyclase activity of the inner membrane protein YfiN, whereas YfiB in the outer membrane can release this inhibition by sequestration of YfiR. In addition, this system may respond to anoxic conditions via YfiR, although the detailed mechanism is still unknown. Here we report crystal structures of Pseudomonas aeruginosa YfiR in the absence and presence of oxidative glutathione. Our structures reveal the overall folding of YfiR for the first time and demonstrate that YfiR exist as a dimer. Comparison of the two structures in different redox states revealed a broken/formation of one disulfide bond (Cys71-Cys110) and local conformational change around the other one (Cys145-Cys152). Mutagenesis studies indicated that Cys145-Cys152 plays an important role in maintaining the correct folding of YfiR.
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Affiliation(s)
- Xuan Yang
- Chinese Academy of Sciences Key Laboratory of Infection and Immunity, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, PR China
| | - Xiu-An Yang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Min Xu
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, PR China
| | - Lei Zhou
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Zusen Fan
- Chinese Academy of Sciences Key Laboratory of Infection and Immunity, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, PR China.
| | - Tao Jiang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, PR China.
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16
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Menendez E, Garcia-Fraile P, Rivas R. Biotechnological applications of bacterial cellulases. AIMS BIOENGINEERING 2015. [DOI: 10.3934/bioeng.2015.3.163] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
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