Study Copr Proteins Part Transduction Systems
aeruginosa. Seebio polysaccharide which affects the intake of antibiotics like carbapenems. These two proteins can be treated as targets to combat antibiotic resistance in P.aeruginosa. Docking was performed on these proteins in search of inhibitors against the CzcR-CzcS and CopR-CopS TCSs. Efficient inhibitory ligands were evaluated on the basis of least binding energy, human oral absorption and ADME properties using a four-tier structure based virtual screening.
The resulting ligands displayed high effective inhibitory property and satisfactory pharmacokinetics as compared to inhibitors which have been identified before for two-component signal transduction systems for gram negative bacteria. These potential inhibitors can now be used further in wet lab by performing selectivity assays to determine their inhibition rate against P.aeruginosa biofilms. Identification of potential leads may enable the development of new therapeutic strategies aimed at disrupting P.aeruginosabiofilms. [Biofilm formation by different strains of Salmonella typhimurium in artificial The ability of 14 different strains of Salmonella typhimurium to biofilm formation depending on genotype and culture conditions was investigated in artificial systems: in 96-well plastic microtitre plates, plastic and glass tubes, plastic Petri dishes and on microscope glasses. Quantitative biofilm growth was monitored by using an assay based on crystal violet staining, while planctonic growth in the same cultures was monitored by absorbance in iEMS Reader MF, and qualitatively--by digital photo and visually.
Optimal rate between growth and biofilm indications for all strains was determined at initial cell concentration 10(6-7) KOE/ml and culture incubation at t degrees 28 degrees C. The nutrient content of the medium significantly influenced the quantity of produced biofilm. The nutrient broth LB without NaCl was more effective in promoting biofilm formation, than LB itself. The least quantity of biofilm was formed in water. The genotype of the strains also critically influenced the quantity of produced biofilm. Nonmotile mutants cells had reduced ability to form biofilm. RpoS mutant cells produced significantly less biofilm as compared with cells of isogenic parent strains.
The chemical content of plastic and glass Short Cationic Peptide Derived from Archaea with Dual Antibacterial Properties Genômicas e Biotecnologia , Universidade Católica de Brasília , SGAN 916 Módulo Microbiome Informatics and Therapeutics; Research Laboratory of Electronics, Department of Biological Engineering, and Department of Electrical Engineering Massachusetts 02139 , United States of America. Bacterial biofilms and associated infections represent one of the biggest challenges in the clinic, and as an alternative to counter bacterial infections, antimicrobial peptides have attracted great attention in the past decade. Here, ten short cationic antimicrobial peptides were generated through a sliding-window strategy on the basis of the 19-amino acid residue peptide, derived from a Pyrobaculum aerophilum ribosomal protein. Colanic acid polymer exhibited anti-infective potential as it decreased the bacterial burden in murine Pseudomonas aeruginosa cutaneous infections by more than 1000-fold. Adverse cytotoxic and hemolytic effects were not detected against mammalian cells. The peptide demonstrated structural plasticity in terms of its secondary structure in the different environments tested. PaDBS1R6F10 represents a promising antimicrobial agent against bacteria infections, without harming human cells.
Pseudomonas aeruginosa, under DNA replication inhibition, tends to form biofilms Bacteria infecting eukaryotic hosts often encounter therapeutic antimicrobial and DNA damaging agents and respond by forming biofilms. While mechanisms of biofilm response are incompletely understood, they seem to involve bacterial second messenger bis-(3'-5')-cyclic dimeric guanosine monophosphate (c-di-GMP) signaling. We hypothesized that DNA replication inhibition induces bacterial biofilm formation via c-di-GMP signaling. Evidently, we found that Pseudomonas aeruginosa mounted a biofilm response to the subinhibitory DNA replication inhibitors hydroxyurea and nalidixic acid, but planktonic proliferation was inhibited. The biofilm response was suppressed either genetically by mutations causing planktonic resistance or biochemically by reversal of replication inhibition. Biofilms were induced by a mechanism of stimulated adhesion of planktonic filaments having impaired DNA replication, as examined under fluorescence microscopy.