1
|
Xu X, Liu F, Qiao W, Dong Y, Yang H, Liu F, Xu H, Qiao M. A Point Mutation in Cassette Relieves the Repression Regulation of CcpA Resulting in an Increase in the Degradation of 2,3-Butanediol in Lactococcus lactis. Microorganisms 2024; 12:773. [PMID: 38674718 PMCID: PMC11051896 DOI: 10.3390/microorganisms12040773] [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: 03/07/2024] [Revised: 04/08/2024] [Accepted: 04/09/2024] [Indexed: 04/28/2024] Open
Abstract
In lactic acid bacteria, the global transcriptional regulator CcpA regulates carbon metabolism by repressing and activating the central carbon metabolism pathway, thus decreasing or increasing the yield of certain metabolites to maximize carbon flow. However, there are no reports on the deregulation of the inhibitory effects of CcpA on the metabolism of secondary metabolites. In this study, we identified a single-base mutant strain of Lactococcus lactis N8-2 that is capable of metabolizing 2,3-butanediol. It has been established that CcpA dissociates from the catabolite responsive element (cre) site due to a mutation, leading to the activation of derepression and expression of the 2,3-butanediol dehydrogenase gene cluster (butB and butA). Transcriptome analysis and quantitative polymerase chain reaction (Q-PCR) results showed significant upregulation of transcription of butB and butA compared to the unmutated strain. Furthermore, micro-scale thermophoresis experiments confirmed that CcpA did not bind to the mutated cre. Furthermore, in a bacterial two-plasmid fluorescent hybridization system, it was similarly confirmed that the dissociation of CcpA from cre eliminated the repressive effect of CcpA on downstream genes. Finally, we investigated the differing catalytic capacities of the 2,3-butanediol dehydrogenase gene cluster in L. lactis N8-1 and L. lactis N8-2 for 2,3-butanediol. This led to increased expression of butB and butA, which were deregulated by CcpA repression. This is the first report on the elimination of the deterrent effect of CcpA in lactic acid bacteria, which changes the direction of enzymatic catalysis and alters the direction of carbon metabolism. This provides new perspectives and strategies for metabolizing 2,3-butanediol using bacteria in synthetic biology.
Collapse
Affiliation(s)
- Xian Xu
- School of Life Science, Shanxi University, Taiyuan 030006, China; (X.X.); (Y.D.); (H.Y.); (F.L.)
| | - Fulu Liu
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China;
| | - Wanjin Qiao
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin 300071, China; (W.Q.); (H.X.)
| | - Yujie Dong
- School of Life Science, Shanxi University, Taiyuan 030006, China; (X.X.); (Y.D.); (H.Y.); (F.L.)
| | - Huan Yang
- School of Life Science, Shanxi University, Taiyuan 030006, China; (X.X.); (Y.D.); (H.Y.); (F.L.)
| | - Fengming Liu
- School of Life Science, Shanxi University, Taiyuan 030006, China; (X.X.); (Y.D.); (H.Y.); (F.L.)
| | - Haijin Xu
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin 300071, China; (W.Q.); (H.X.)
| | - Mingqiang Qiao
- School of Life Science, Shanxi University, Taiyuan 030006, China; (X.X.); (Y.D.); (H.Y.); (F.L.)
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin 300071, China; (W.Q.); (H.X.)
| |
Collapse
|
2
|
Lyon SE, Wencker FDR, Fernando CM, Harris KA, Breaker RR. Disruption of the bacterial OLE RNP complex impairs growth on alternative carbon sources. PNAS NEXUS 2024; 3:pgae075. [PMID: 38415217 PMCID: PMC10898510 DOI: 10.1093/pnasnexus/pgae075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2023] [Accepted: 02/06/2024] [Indexed: 02/29/2024]
Abstract
Ornate, large, extremophilic (OLE) RNAs comprise a class of large noncoding RNAs in bacteria whose members form a membrane-associated ribonucleoprotein (RNP) complex. This complex facilitates cellular adaptation to diverse stresses such as exposure to cold, short-chain alcohols, and elevated Mg2+ concentrations. Here, we report additional phenotypes exhibited by Halalkalibacterium halodurans (formerly called Bacillus halodurans) strains lacking functional OLE RNP complexes. Genetic disruption of the complex causes restricted growth compared to wild-type cells when cultured in minimal media (MM) wherein glucose is replaced with alternative carbon/energy sources. Genetic suppressor selections conducted in glutamate MM yielded isolates that carry mutations in or near genes relevant to Mn2+ homeostasis (ykoY and mntB), phosphate homeostasis (phoR), and putative multidrug resistance (bmrCD). These functional links between OLE RNA, carbon/energy management, and other fundamental processes including protein secretion are consistent with the hypothesis that the OLE RNP complex is a major contributor to cellular adaptation to unfavorable growth conditions.
Collapse
Affiliation(s)
- Seth E Lyon
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA
| | - Freya D R Wencker
- Howard Hughes Medical Institute, Yale University, New Haven, CT 06511, USA
| | - Chrishan M Fernando
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA
| | - Kimberly A Harris
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT 06511, USA
| | - Ronald R Breaker
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA
- Howard Hughes Medical Institute, Yale University, New Haven, CT 06511, USA
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT 06511, USA
| |
Collapse
|
3
|
Liu Y, Long S, Wang H, Wang Y. Biofilm therapy for chronic wounds. Int Wound J 2024; 21:e14667. [PMID: 38339793 PMCID: PMC10858329 DOI: 10.1111/iwj.14667] [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: 09/23/2023] [Revised: 12/24/2023] [Accepted: 12/29/2023] [Indexed: 02/12/2024] Open
Abstract
Chronic wounds have been a major factor of serious harm to global public health. At present, it is known that almost all chronic wounds contain biofilms, which seriously hinder the healing process. Removal of biofilms can effectively promote the healing of chronic wounds. As the study of wound biofilms deepens, many new treatment methods have emerged, thus bringing revolutionary means for the treatment of chronic wound biofilm. This review summarizes various methods for the treatment of chronic wound biofilm worldwide to provide a theoretical summary and practical basis for the selection of suitable wound biofilm treatment methods in clinical practice.
Collapse
Affiliation(s)
- Yang Liu
- Center of Gastrointestinal and Minimally Invasive Surgery, Department of General Surgery, The Third People's Hospital of ChengduAffiliated Hospital of Southwest Jiaotong UniversityChengduChina
| | - Shengyong Long
- Department of TraumatologyTongren People's HospitalTongrenChina
| | - Hanfeng Wang
- Plastic Surgery DepartmentXi'an International Medical Center HospitalXi'anChina
| | - Yan Wang
- Center of Gastrointestinal and Minimally Invasive Surgery, Department of General Surgery, The Third People's Hospital of ChengduAffiliated Hospital of Southwest Jiaotong UniversityChengduChina
- Medical Research Center, The Third People's Hospital of ChengduAffiliated Hospital of Southwest Jiaotong UniversityChengduChina
| |
Collapse
|
4
|
Viering B, Balogh H, Cox CF, Kirpekar OK, Akers AL, Federico VA, Valenzano GZ, Stempel R, Pickett HL, Lundin PM, Blackledge MS, Miller HB. Loratadine Combats Methicillin-Resistant Staphylococcus aureus by Modulating Virulence, Antibiotic Resistance, and Biofilm Genes. ACS Infect Dis 2024; 10:232-250. [PMID: 38153409 PMCID: PMC10788911 DOI: 10.1021/acsinfecdis.3c00616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 12/12/2023] [Accepted: 12/14/2023] [Indexed: 12/29/2023]
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) has evolved to become resistant to multiple classes of antibiotics. New antibiotics are costly to develop and deploy, and they have a limited effective lifespan. Antibiotic adjuvants are molecules that potentiate existing antibiotics through nontoxic mechanisms. We previously reported that loratadine, the active ingredient in Claritin, potentiates multiple cell-wall active antibiotics in vitro and disrupts biofilm formation through a hypothesized inhibition of the master regulatory kinase Stk1. Loratadine and oxacillin combined repressed the expression of key antibiotic resistance genes in the bla and mec operons. We hypothesized that additional genes involved in antibiotic resistance, biofilm formation, and other cellular pathways would be modulated when looking transcriptome-wide. To test this, we used RNA-seq to quantify transcript levels and found significant effects in gene expression, including genes controlling virulence, antibiotic resistance, metabolism, transcription (core RNA polymerase subunits and sigma factors), and translation (a plethora of genes encoding ribosomal proteins and elongation factor Tu). We further demonstrated the impacts of these transcriptional effects by investigating loratadine treatment on intracellular ATP levels, persister formation, and biofilm formation and morphology. Loratadine minimized biofilm formation in vitro and enhanced the survival of infected Caenorhabditis elegans. These pleiotropic effects and their demonstrated outcomes on MRSA virulence and survival phenotypes position loratadine as an attractive anti-infective against MRSA.
Collapse
Affiliation(s)
- Brianna
L. Viering
- Department
of Chemistry, High Point University, High Point, North Carolina 27268, United States
| | - Halie Balogh
- Department
of Chemistry, High Point University, High Point, North Carolina 27268, United States
| | - Chloe F. Cox
- Department
of Chemistry, High Point University, High Point, North Carolina 27268, United States
| | - Owee K. Kirpekar
- Department
of Chemistry, High Point University, High Point, North Carolina 27268, United States
| | - A. Luke Akers
- Department
of Chemistry, High Point University, High Point, North Carolina 27268, United States
| | - Victoria A. Federico
- Department
of Biology, High Point University, High Point, North Carolina 27268, United States
| | - Gabriel Z. Valenzano
- Department
of Chemistry, High Point University, High Point, North Carolina 27268, United States
| | - Robin Stempel
- Department
of Chemistry, High Point University, High Point, North Carolina 27268, United States
| | - Hannah L. Pickett
- Department
of Biology, High Point University, High Point, North Carolina 27268, United States
| | - Pamela M. Lundin
- Department
of Chemistry, High Point University, High Point, North Carolina 27268, United States
| | - Meghan S. Blackledge
- Department
of Chemistry, High Point University, High Point, North Carolina 27268, United States
| | - Heather B. Miller
- Department
of Chemistry, High Point University, High Point, North Carolina 27268, United States
| |
Collapse
|
5
|
Zhang A, Wu H, Chen X, Chen Z, Pan Y, Qu W, Hao H, Chen D, Xie S. Targeting and arginine-driven synergizing photodynamic therapy with nutritional immunotherapy nanosystems for combating MRSA biofilms. SCIENCE ADVANCES 2023; 9:eadg9116. [PMID: 37450586 PMCID: PMC10348676 DOI: 10.1126/sciadv.adg9116] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Accepted: 06/09/2023] [Indexed: 07/18/2023]
Abstract
The resistance and immune escape of methicillin-resistant Staphylococcus aureus (MRSA) biofilms cause recalcitrant infections. Here, we design a targeting and synergizing cascade PDT with nutritional immunotherapy nanosystems (Arg-PCN@Gel) containing PCN-224 as PDT platform for providing reactive oxygen species (ROS), incorporating arginine (Arg) as nitric oxide (NO) donor to cascade with ROS to produce more lethal ONOO- and promote immune response, and coating with gelatin as targeting agent and persistent Arg provider. The nanosystems adhered to the autolysin of MRSA and inhibited Arg metabolism by down-regulating icdA and icaA. It suppressed polysaccharide intercellular adhesin and extracellular DNA synthesis to prevent biofilm formation. The NO broke mature biofilms and helped ROS and ONOO- penetrate into biofilms to inactivate internal MRSA. Arg-PCN@Gel drove Arg to enhance immunity via inducible NO synthase/NO axis and arginase/polyamine axis and achieve efficient target treatment in MRSA biofilm infections. The targeting and cascading PDT synergized with nutritional immunotherapy provide an effective promising strategy for biofilm-associated infections.
Collapse
Affiliation(s)
- Aoxue Zhang
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, Hubei 430070, China
| | - Hao Wu
- National Reference Laboratory of Veterinary Drug Residues (HZAU) and MAO Key Laboratory for Detection of Veterinary Drug Residues, Wuhan, Hubei 430070, China
| | - Xin Chen
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, Hubei 430070, China
| | - Zhen Chen
- Key Laboratory of Prevention & Control for African Swine Fever and Other Major Pig Diseases, Ministry of Agriculture and Rural Affairs,Wuhan, Hubei 430070, China
| | - Yuanhu Pan
- Key Laboratory of Prevention & Control for African Swine Fever and Other Major Pig Diseases, Ministry of Agriculture and Rural Affairs,Wuhan, Hubei 430070, China
| | - Wei Qu
- Key Laboratory of Prevention & Control for African Swine Fever and Other Major Pig Diseases, Ministry of Agriculture and Rural Affairs,Wuhan, Hubei 430070, China
| | - Haihong Hao
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, Hubei 430070, China
| | - Dongmei Chen
- Key Laboratory of Prevention & Control for African Swine Fever and Other Major Pig Diseases, Ministry of Agriculture and Rural Affairs,Wuhan, Hubei 430070, China
| | - Shuyu Xie
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, Hubei 430070, China
- National Reference Laboratory of Veterinary Drug Residues (HZAU) and MAO Key Laboratory for Detection of Veterinary Drug Residues, Wuhan, Hubei 430070, China
- Key Laboratory of Prevention & Control for African Swine Fever and Other Major Pig Diseases, Ministry of Agriculture and Rural Affairs,Wuhan, Hubei 430070, China
| |
Collapse
|
6
|
Zhao A, Sun J, Liu Y. Understanding bacterial biofilms: From definition to treatment strategies. Front Cell Infect Microbiol 2023; 13:1137947. [PMID: 37091673 PMCID: PMC10117668 DOI: 10.3389/fcimb.2023.1137947] [Citation(s) in RCA: 31] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Accepted: 03/09/2023] [Indexed: 04/08/2023] Open
Abstract
Bacterial biofilms are complex microbial communities encased in extracellular polymeric substances. Their formation is a multi-step process. Biofilms are a significant problem in treating bacterial infections and are one of the main reasons for the persistence of infections. They can exhibit increased resistance to classical antibiotics and cause disease through device-related and non-device (tissue) -associated infections, posing a severe threat to global health issues. Therefore, early detection and search for new and alternative treatments are essential for treating and suppressing biofilm-associated infections. In this paper, we systematically reviewed the formation of bacterial biofilms, associated infections, detection methods, and potential treatment strategies, aiming to provide researchers with the latest progress in the detection and treatment of bacterial biofilms.
Collapse
Affiliation(s)
- Ailing Zhao
- Department of Gastroenterology, Yantai Affiliated Hospital of Binzhou Medical University, Yantai, Shandong, China
| | - Jiazheng Sun
- Department of Vasculocardiology, Jinzhou Medical University, Jinzhou, Liaoning, China
| | - Yipin Liu
- Department of Gastroenterology, Yantai Affiliated Hospital of Binzhou Medical University, Yantai, Shandong, China
- *Correspondence: Yipin Liu,
| |
Collapse
|
7
|
Dresen M, Valentin-Weigand P, Berhanu Weldearegay Y. Role of Metabolic Adaptation of Streptococcus suis to Host Niches in Bacterial Fitness and Virulence. Pathogens 2023; 12:pathogens12040541. [PMID: 37111427 PMCID: PMC10144218 DOI: 10.3390/pathogens12040541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 03/24/2023] [Accepted: 03/27/2023] [Indexed: 04/03/2023] Open
Abstract
Streptococcus suis, both a common colonizer of the porcine upper respiratory tract and an invasive pig pathogen, successfully adapts to different host environments encountered during infection. Whereas the initial infection mainly occurs via the respiratory tract, in a second step, the pathogen can breach the epithelial barrier and disseminate within the whole body. Thereby, the pathogen reaches other organs such as the heart, the joints, or the brain. In this review, we focus on the role of S. suis metabolism for adaptation to these different in vivo host niches to encounter changes in nutrient availability, host defense mechanisms and competing microbiota. Furthermore, we highlight the close link between S. suis metabolism and virulence. Mutants deficient in metabolic regulators often show an attenuation in infection experiments possibly due to downregulation of virulence factors, reduced resistance to nutritive or oxidative stress and to phagocytic activity. Finally, metabolic pathways as potential targets for new therapeutic strategies are discussed. As antimicrobial resistance in S. suis isolates has increased over the last years, the development of new antibiotics is of utmost importance to successfully fight infections in the future.
Collapse
Affiliation(s)
- Muriel Dresen
- Institute for Microbiology, University of Veterinary Medicine Hannover, 30173 Hannover, Germany
| | - Peter Valentin-Weigand
- Institute for Microbiology, University of Veterinary Medicine Hannover, 30173 Hannover, Germany
| | | |
Collapse
|
8
|
Costa MDOCE, do Nascimento APB, Martins YC, dos Santos MT, Figueiredo AMDS, Perez-Rueda E, Nicolás MF. The gene regulatory network of Staphylococcus aureus ST239-SCC mecIII strain Bmb9393 and assessment of genes associated with the biofilm in diverse backgrounds. Front Microbiol 2023; 13:1049819. [PMID: 36704545 PMCID: PMC9871828 DOI: 10.3389/fmicb.2022.1049819] [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: 09/21/2022] [Accepted: 12/19/2022] [Indexed: 01/12/2023] Open
Abstract
Introduction Staphylococcus aureus is one of the most prevalent and relevant pathogens responsible for a wide spectrum of hospital-associated or community-acquired infections. In addition, methicillin-resistant Staphylococcus aureus may display multidrug resistance profiles that complicate treatment and increase the mortality rate. The ability to produce biofilm, particularly in device-associated infections, promotes chronic and potentially more severe infections originating from the primary site. Understanding the complex mechanisms involved in planktonic and biofilm growth is critical to identifying regulatory connections and ways to overcome the global health problem of multidrug-resistant bacteria. Methods In this work, we apply literature-based and comparative genomics approaches to reconstruct the gene regulatory network of the high biofilm-producing strain Bmb9393, belonging to one of the highly disseminating successful clones, the Brazilian epidemic clone. To the best of our knowledge, we describe for the first time the topological properties and network motifs for the Staphylococcus aureus pathogen. We performed this analysis using the ST239-SCCmecIII Bmb9393 strain. In addition, we analyzed transcriptomes available in the literature to construct a set of genes differentially expressed in the biofilm, covering different stages of the biofilms and genetic backgrounds of the strains. Results and discussion The Bmb9393 gene regulatory network comprises 1,803 regulatory interactions between 64 transcription factors and the non-redundant set of 1,151 target genes with the inclusion of 19 new regulons compared to the N315 transcriptional regulatory network published in 2011. In the Bmb9393 network, we found 54 feed-forward loop motifs, where the most prevalent were coherent type 2 and incoherent type 2. The non-redundant set of differentially expressed genes in the biofilm consisted of 1,794 genes with functional categories relevant for adaptation to the variable microenvironments established throughout the biofilm formation process. Finally, we mapped the set of genes with altered expression in the biofilm in the Bmb9393 gene regulatory network to depict how different growth modes can alter the regulatory systems. The data revealed 45 transcription factors and 876 shared target genes. Thus, the gene regulatory network model provided represents the most up-to-date model for Staphylococcus aureus, and the set of genes altered in the biofilm provides a global view of their influence on biofilm formation from distinct experimental perspectives and different strain backgrounds.
Collapse
Affiliation(s)
| | - Ana Paula Barbosa do Nascimento
- Departamento de Análises Clínicas e Toxicológicas, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, São Paulo, Brazil
| | | | | | - Agnes Marie de Sá Figueiredo
- Instituto de Investigaciones en Matemáticas Aplicadas y en Sistemas, Universidad Nacional Autónoma de México, Unidad Académica Yucatán, Merida, Mexico
| | - Ernesto Perez-Rueda
- Laboratório de Biologia Molecular de Bactérias, Instituto de Microbiologia Paulo de Goés, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil,*Correspondence: Ernesto Perez-Rueda ✉
| | - Marisa Fabiana Nicolás
- Laboratório Nacional de Computação Científica (LNCC), Petrópolis, Brazil,Marisa Fabiana Nicolás ✉
| |
Collapse
|
9
|
Zheng M, Zhu K, Peng H, Shang W, Zhao Y, Lu S, Rao X, Li M, Zhou R, Li G. CcpA Regulates Staphylococcus aureus Biofilm Formation through Direct Repression of Staphylokinase Expression. Antibiotics (Basel) 2022; 11:antibiotics11101426. [PMID: 36290085 PMCID: PMC9598941 DOI: 10.3390/antibiotics11101426] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 10/08/2022] [Accepted: 10/13/2022] [Indexed: 11/16/2022] Open
Abstract
Staphylococcus aureus represents a notorious opportunistic pathogen causing various infections in biofilm nature, imposing remarkable therapeutic challenges worldwide. The catabolite control protein A (CcpA), a major regulator of carbon catabolite repression (CCR), has been recognized to modulate S. aureus biofilm formation, while the underlying mechanism remains to be fully elucidated. In this study, the reduced biofilm was firstly determined in the ccpA deletion mutant of S. aureus clinical isolate XN108 using both crystal violet staining and confocal laser scanning microscopy. RNA-seq analysis suggested that sak-encoding staphylokinase (Sak) was significantly upregulated in the mutant ∆ccpA, which was further confirmed by RT-qPCR. Consistently, the induced Sak production correlated the elevated promoter activity of sak and increased secretion in the supernatants, as demonstrated by Psak-lacZ reporter fusion expression and chromogenic detection, respectively. Notably, electrophoretic mobility shift assays showed that purified recombinant protein CcpA binds directly to the promoter region of sak, suggesting the direct negative control of sak expression by CcpA. Double isogenic deletion of ccpA and sak restored biofilm formation for mutant ∆ccpA, which could be diminished by trans-complemented sak. Furthermore, the exogenous addition of recombinant Sak inhibited biofilm formation for XN108 in a dose-dependent manner. Together, this study delineates a novel model of CcpA-controlled S. aureus biofilm through direct inhibition of sak expression, highlighting the multifaceted roles and multiple networks regulated by CcpA.
Collapse
Affiliation(s)
- Mingxia Zheng
- Department of Emergency Medicine, Xinqiao Hospital, Army Medical University, Chongqing 400037, China
| | - Keting Zhu
- Department of Emergency Medicine, Xinqiao Hospital, Army Medical University, Chongqing 400037, China
| | - Huagang Peng
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University, Chongqing 400038, China
| | - Weilong Shang
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University, Chongqing 400038, China
| | - Yan Zhao
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University, Chongqing 400038, China
| | - Shuguang Lu
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University, Chongqing 400038, China
| | - Xiancai Rao
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University, Chongqing 400038, China
| | - Ming Li
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University, Chongqing 400038, China
- Correspondence: (M.L.); (R.Z.); (G.L.)
| | - Renjie Zhou
- Department of Emergency Medicine, Xinqiao Hospital, Army Medical University, Chongqing 400037, China
- Correspondence: (M.L.); (R.Z.); (G.L.)
| | - Gang Li
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University, Chongqing 400038, China
- Correspondence: (M.L.); (R.Z.); (G.L.)
| |
Collapse
|