Chemical inhibition of MrkH-dependent activation of type 3 fimbriae synthesis and biofilm formation by Klebsiella pneumoniae

Abstract

Biofilm formation by Klebsiella pneumoniae is mediated by the type 3 fimbriae Mrk, and regulated by MrkH and 3’,5’-cyclic diguanylic acid (c-di-GMP). We sought to identify specific chemical inhibitors of K. pneumoniae biofilm formation that reduced the activity of MrkH. A compound N-(3-cyano-5,6,7,8-tetrahydro-4H-cyclohepta[b]thien-2-yl)-2-methoxybenzamide, JT71, reduced K. pneumoniae mrkA promoter activity and biofilm formation by 50% without affecting cell viability. Western blot analysis, hemagglutination assays, electron microscopy and qPCR showed that JT71 reduced type 3 fimbriae production, and transcription of mrkA and mrkH. JT71 demonstrated activity against other clinical and multi-..