Microbial metalloproteinases mediate sensing of invading pathogens and activate innate immune responses in the lepidopteran model host Galleria mellonella.

ABSTRACT: Thermolysin-like metalloproteinases such as aureolysin, pseudolysin, and bacillolysin represent virulence factors of diverse bacterial pathogens. Recently, we discovered that injection of thermolysin into larvae of the greater wax moth, Galleria mellonella, mediated strong immune responses. Thermolysin-mediated proteolysis of hemolymph proteins yielded a variety of small-sized (<3 kDa) protein fragments (protfrags) that are potent elicitors of innate immune responses. In this study, we report the activation of a serine proteinase cascade by thermolysin, as described for bacterial lipopolysaccharides (LPS), that results in subsequent prophenoloxidase activation leading to melanization, an elementary immune defense reaction of insects. Quantitative real-time reverse transcription-PCR analyse

SUBMITTER: Altincicek B 

PROVIDER: S-EPMC1828416 | biostudies-literature | 2007 Jan

REPOSITORIES: biostudies-literature