, a major bacterial porcine respiratory tract pathogen causing pig pleuropneumonia, has resulted in high economic losses worldwide. The mutation of the two-component system CpxAR strongly impacted the virulence of , but the underlying regulatory mechanism remained unclear. Here, we found that CpxAR positively regulated the gene cluster involved in polysaccharide capsule export. A capsular layer was confirmed in wild-type cells by transmission electron microscopy, whereas and mutants were non-capsulated. The mutants for polysaccharide capsule export gene exhibited non-capsulated and were strongly impaired in virulence for mice, indicating a major role of CPS export system in virulence. We then demonstrated that CpxR directly regulated the transcription of the CPS export gene cluster . Taken together, our data suggested that CpxAR is a key modulator of capsule export that facilitates survival in the host.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9615922 | PMC |
| http://dx.doi.org/10.3389/fmicb.2022.1029426 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Cell wall melanin impedes growth of the polysaccharide capsule by sequestering calcium.
Proc Natl Acad Sci U S A
September 2024
Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205.
has emerged as a frontrunner among deadly fungal pathogens and is particularly life-threatening for many HIV-infected individuals with compromised immunity. Multiple virulence factors contribute to the growth and survival of within the human host, the two most prominent of which are the polysaccharide capsule and melanin. As both of these features are associated with the cell wall, we were interested to explore possible cooperative or competitive interactions between these two virulence factors.
View Article and Find Full Text PDFA computational model for lipid-anchored polysaccharide export by the outer membrane protein GfcD.
Biophys J
October 2024
Department of Protein Evolution, Max Planck Institute for Biology Tübingen, Tübingen, Germany. Electronic address:
Article Synopsis
- - Many bacteria have protective polysaccharide capsules made of long glycan chains, which can be free or attached to their outer membrane; the group 4 capsule in E. coli is produced by a specific gene operon.
- - The GfcD protein, part of this operon, is believed to function as a channel for exporting lipid-anchored polysaccharide chains and has two predicted β-barrel domains that could serve as a lateral exit gate.
- - A study using molecular dynamics showed that while the lateral aperture of GfcD remains stable, lipids do not enter the barrel, but lipid A successfully exits into the membrane, indicating how the capsule is exported.
CT scan-based 3D fracture mapping in civilian gunshot intracapsular fractures of the femur neck.
Injury
October 2024
Orthopaedic Trauma Service, Division of Orthopaedic Surgery, University of Cape Town.
Introduction: Displaced intracapsular neck of femur (NOF) fractures secondary to civilian gunshots are rare injuries with universally poor outcomes following surgical fixation. No studies have been published on fracture mapping in NOF fractures secondary to civilian gunshots.
Objectives: We performed CT scan-based fracture mapping to identify the most common fracture patterns in these injuries.
Evolutionary genomic analyses of canine infections identify a relic capsular locus associated with resistance to multiple classes of antimicrobials.
Appl Environ Microbiol
August 2024
Cornell University, Ithaca, New York, USA.
Unlabelled: Infections caused by antimicrobial-resistant are the leading cause of death attributed to antimicrobial resistance (AMR) worldwide, and the known AMR mechanisms involve a range of functional proteins. Here, we employed a pan-genome wide association study (GWAS) approach on over 1,000 isolates from sick dogs collected across the US and Canada and identified a strong statistical association (empirical < 0.01) of AMR, involving a range of antibiotics to a group 1 capsular (CPS) gene cluster.
View Article and Find Full Text PDFThe mycobacterial glycoside hydrolase LamH enables capsular arabinomannan release and stimulates growth.
Nat Commun
July 2024
School of Biosciences, University of Birmingham, Birmingham, UK.
Mycobacterial glycolipids are important cell envelope structures that drive host-pathogen interactions. Arguably, the most important are lipoarabinomannan (LAM) and its precursor, lipomannan (LM), which are trafficked from the bacterium to the host via unknown mechanisms. Arabinomannan is thought to be a capsular derivative of these molecules, lacking a lipid anchor.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!