The relative impact of 23 mutations on biofilm formation was evaluated in the USA300, methicillin-resistant strain LAC. Mutation of sarA, atl, codY, rsbU, and sigB limited biofilm formation in comparison to the parent strain, but the limitation imposed by mutation of sarA was greater than that imposed by mutation of any of these other genes. The reduced biofilm formation of all mutants other than the atl mutant was correlated with increased levels of extracellular proteases. Mutation of fur- and mgrA-enhanced biofilm formation but in LAC had no impact on protease activity, nuclease activity, or accumulation of the polysaccharide intercellular adhesin (PIA). The increased capacity of these mutants to form a biofilm was reversed by mutation of sarA, and this was correlated with increased protease production. Mutation of sarA, mgrA, and sigB had the same phenotypic effect in the methicillin-sensitive strain UAMS-1, but mutation of codY increased rather than decreased biofilm formation. As with the UAMS-1 mgrA mutant, this was correlated with increased production of PIA. Examination of four additional clinical isolates suggests that the differential impact of codY on biofilm formation may be a conserved characteristic of methicillin-resistant versus methicillin-sensitive strains.
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http://dx.doi.org/10.1002/mbo3.250 | DOI Listing |
BMC Microbiol
January 2025
The First Affiliated Hospital of Xinxiang Medical University, Xinxiang, China.
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View Article and Find Full Text PDFNPJ Biofilms Microbiomes
January 2025
Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky Prospekt 47, Moscow, 119991, Russia.
Biofilms are critical for understanding environmental processes, developing biotechnology applications, and progressing in medical treatments of various infections. Nowadays, a key limiting factor for biofilm analysis is the difficulty in obtaining large datasets with fully annotated images. This study introduces a versatile approach for creating synthetic datasets of annotated biofilm images with employing deep generative modeling techniques, including VAEs, GANs, diffusion models, and CycleGAN.
View Article and Find Full Text PDFBioorg Chem
January 2025
Chemistry Department, Faculty of Science, Ain Shams University, Abbasia, 11566 Cairo, Egypt.
The escalating prevalence of antibiotic-resistant bacteria has led to a serious global public health problem; therefore, there is an urgent need for the development of structurally innovative antibacterial agents. In our study, different series of tetra-substituted thiophene derivatives were designed and synthesized by multi-component reactions (MCRs) in moderate to excellent yields. Some of the designed final compounds were synthesized by both microwave assisted method and traditional synthesis.
View Article and Find Full Text PDFBraz J Microbiol
January 2025
ICAR-Central Institute of Fisheries Technology (ICAR-CIFT), Willingdon Island, Cochin, Kerala, 682029, India.
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