Aspergillus oryzae attenuates quorum sensing -associated virulence factors and biofilm formation in Klebsiella pneumoniae extended-spectrum beta-lactamases

Background: Klebsiella pneumoniae communicate between and among species using quorum sensing (QS). Biofilm formation virulence factors are regulated by QS. This QS is indirectly responsible for K. pathogenicity. Inhibiting a novel highly effective method controlling extended-spectrum beta-lactamases (KP-ESBL) infections. study aimed to investigate how Aspergillus oryzae extracellular protein (AOEP) affected KP-ESBL factors. Methods: Methods used included minimal inhibitory concentration (MIC) through the microdilution method, biofilms with crystal violet staining, polysaccharides Congo Red assay, quantifying expression of genes coding capsular polysaccharide (wzI gene) adhesion (mrkA gene) quantitative reverse-transcription polymerase chain reaction (RT-qPCR), siderophore level measurement Chrome Azurol sulphonate assay (CAS assay), biofilm morphology scanning electron microscope (SEM), confirmation life span killing on Caenorhabditis elegans (C. elegans). Results: In vitro studies revealed that AOEP inhibited exopolysaccharides (EPS) in at sub-MIC level. In addition, mrkA gene, which involved process. Furthermore, an in vivo levels 75 150 µg/mL respectively increased C. survival rates 72.67% 80.76% against infection. Conclusions: Our findings suggest A. may be inhibitor anti-virulence agent control bacterial pathogens.