Identification and Characterization of RK22, a Novel Antimicrobial Peptide from Hirudinaria manillensis against Methicillin Resistant Staphylococcus aureus
Basic science / preclinical published in Int J Mol Sci (2023)
Abstract
Staphylococcus aureus (S. aureus) infections are a leading cause of morbidity and mortality, which are compounded by drug resistance. By manipulating the coagulation system, S. aureus gains a significant advantage over host defense mechanisms, with hypercoagulation induced by S. aureus 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 S. aureus 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 Hirudinaria manillensis (H. manillensis) through bioinformatic analysis, and then synthesized it, which exhibited good antimicrobial activity against S. aureus, including a clinically resistant strain with a minimal inhibitory concentration (MIC) of 6.25 μg/mL. The RK22 peptide rapidly killed S. aureus 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 S. aureus infection and the clinically resistant strain in vivo. Thus, these findings highlight the potential of RK22 as an ideal treatment candidate against S. aureus infection.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
Identification of RK22, a novel antimicrobial peptide from the salivary gland transcriptome of Hirudinaria manillensis, with MIC 6.25 ug/mL against MRSA. Demonstrates biofilm inhibition, plasma stability, low cytotoxicity, and in-vivo MRSA-clearance efficacy.
Why This Matters for Hirudotherapy
This study identified RK22, a novel antimicrobial peptide from the salivary gland transcriptome of Hirudinaria manillensis, via bioinformatic analysis and chemical synthesis. RK22 exhibited antimicrobial activity against Staphylococcus aureus including a clinically resistant strain (MIC 6.25 μg/mL), killing S. aureus by inhibiting biofilm formation and promoting biofilm eradication, with good plasma stability, negligible cytotoxicity, minimal hemolytic activity, and no significant coagulation-system promotion. Administration of RK22 significantly inhibited S. aureus infection and the clinically resistant strain in vivo. For ASH's domain, this is relevant as a characterization of a bioactive peptide from a leech salivary gland with antimicrobial properties. The caveat is that while in vivo data are presented, no human trials or clinical efficacy claims are reported in the abstract.
Citation
Identification and Characterization of RK22, a Novel Antimicrobial Peptide from Hirudinaria manillensis against Methicillin Resistant Staphylococcus aureus.
Lu X et al. · International journal of molecular sciences, 2023
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