In vitro and in vivo efficacy of Caenorhabditis elegans recombinant antimicrobial protein against Gram-negative bacteria.

Antimicrobial peptides (AMPs) are short, positively charged host defense peptides, found in various life forms from microorganisms to humans. AMPs are gaining more attention as substitutes for antibiotics in order to combat the risk posed by multi-drug- resistant pathogens. The nematode Caenorhabditis elegans relies solely on its innate immune defense to cope with its challenging life-style. Bacterial infection in C. elegans leads to induction of antimicrobial proteins, defensins, nemapores, cecropins, and neuropeptide-like proteins, which act to limit bacterial proliferation. This study reports how the C. elegans recombinant antibacterial factor (ABF-1) rapidly inhibited bacterial growth (Salmonella Typhi, Klebsiella pneumonia, Shigella sonnei and Vibrio alginolyticus). The ABF-1 exposure on S. Typhi, showed differential regulation in cell-cycle, DNA repair mechanism, membrane stability, and stress related proteins. The exogenous supply of ABF-1 protein has extended C. elegans survival by reducing the bacterial colony forming units on the nematode intestine. Together, these findings indicate the valuable and potential therapeutic applications of ABF-1 protein as antimicrobial agents against intracellular pathogens.