Identification and Characterization of RK22, a Novel Antimicrobial Peptide from against Methicillin Resistant .

() infections are a leading cause of morbidity and mortality, which are compounded by drug resistance. By manipulating the coagulation system, gains a significant advantage over host defense mechanisms, with hypercoagulation induced by potentially aggravating infectious diseases. Recently, we and other researchers identified that a higher level of LL-37, one endogenous antimicrobial peptide with a significant killing effect on infection, resulted in thrombosis formation through the induction of platelet activation and potentiation of the coagulation factor enzymatic activity. In the current study, we identified a novel antimicrobial peptide (RK22) from the salivary gland transcriptome of () through bioinformatic analysis, and then synthesized it, which exhibited good antimicrobial activity against , including a clinically resistant strain with a minimal inhibitory concentration (MIC) of 6.25 μg/mL. The RK22 peptide rapidly killed by inhibiting biofilm formation and promoting biofilm eradication, with good plasma stability, negligible cytotoxicity, minimal hemolytic activity, and no significant promotion of the coagulation system. Notably, administration of RK22 significantly inhibited infection and the clinically resistant strain in vivo. Thus, these findings highlight the potential of RK22 as an ideal treatment candidate against infection.