Department of Zoology, University of Oxford, Oxford, United Kingdom; Oxford Centre for Integrative Systems Biology, University of Oxford, Oxford, United Kingdom; FAS Center for Systems Biology, University of Harvard, Cambridge, Massachusetts, United States of America.
Published: July 2015
AI Article Synopsis
Article Abstract
Bacteria form dense surface-associated communities known as biofilms that are central to their persistence and how they affect us. Biofilm formation is commonly viewed as a cooperative enterprise, where strains and species work together for a common goal. Here we explore an alternative model: biofilm formation is a response to ecological competition. We co-cultured a diverse collection of natural isolates of the opportunistic pathogen Pseudomonas aeruginosa and studied the effect on biofilm formation. We show that strain mixing reliably increases biofilm formation compared to unmixed conditions. Importantly, strain mixing leads to strong competition: one strain dominates and largely excludes the other from the biofilm. Furthermore, we show that pyocins, narrow-spectrum antibiotics made by other P. aeruginosa strains, can stimulate biofilm formation by increasing the attachment of cells. Side-by-side comparisons using microfluidic assays suggest that the increase in biofilm occurs due to a general response to cellular damage: a comparable biofilm response occurs for pyocins that disrupt membranes as for commercial antibiotics that damage DNA, inhibit protein synthesis or transcription. Our data show that bacteria increase biofilm formation in response to ecological competition that is detected by antibiotic stress. This is inconsistent with the idea that sub-lethal concentrations of antibiotics are cooperative signals that coordinate microbial communities, as is often concluded. Instead, our work is consistent with competition sensing where low-levels of antibiotics are used to detect and respond to the competing genotypes that produce them.
Introduction: Typhoid fever is an infectious disease primarily caused by sv. Typhi ( Typhi), a bacterium that causes as many as 20 million infections and 600,000 deaths annually. Asymptomatic chronic carriers of S.
Biofilm-associated peri-implant infections pose a major problem in modern medicine. The understanding of biofilm development is hampered by biofilm complexity and the lack of robust clinical models. This study comprehensively characterized the dynamics of early biofilm formation in the transmucosal passage of implant abutments in 12 patients.
Clinical symptoms of infection (CDI) range from diarrhea to pseudomembranous colitis. A major challenge in managing CDI is the high rate of relapse. Several studies correlate the production of CDT binary toxin by clinical strains of with higher relapse rates.
Dipeptides were constructed using hydrophobic amino acid residues following AMP prediction. After that Boc-modification was performed on the screened peptides and finally Boc-Phe-Trp-OMe and Boc-Trp-Trp-OMe were synthesized. Even though no inhibition zones were observed in agar well diffusion assays, minimum inhibitory concentration (MIC) analysis revealed anti-bacterial activity against both Gram-positive and Gram-negative bacteria, with MIC ranging from 230 to 400 μg/mL.
Department of Laboratory Medicine, The Affiliated Changsha Hospital of Xiangya School of Medicine (The First Hospital of Changsha), Central South University, No. 311, Yingpan Road, Changsha, 410005, Hunan, China.
Antibiotic resistance by methicillin-resistant Staphylococcus aureus (MRSA) is an urgent threat to human health. The biofilm and persister cells formation ability of MRSA and Staphylococcus epidermidis often companied with extremely high antimicrobial resistance. Pinaverium bromide (PVB) is an antispasmodic compound mainly used for irritable bowel syndrome.
