Title Potent antibacterial and antibiofilm activities of TICbf-14, a peptide with increased stability against trypsin
Author Liping Wang, Xiaoyun Liu, Xinyue Ye, Chenyu Zhou, Wenxuan Zhao, Changlin Zhou*, and Lingman Ma*
Address School of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu 211198, P. R. China
Bibliography Journal of Microbiology, 60(1),89-99, 2022,
DOI 10.1007/s12275-022-1368-9
Key Words TICbf-14, trypsin inhibition, antimicrobial activity, biofilm inhibition, ionic bridge, membrane-disruptive mode
Abstract The poor stability of peptides against trypsin largely limits their development as potential antibacterial agents. Here, to obtain a peptide with increased trypsin stability and potent antibacterial activity, TICbf-14 derived from the cationic peptide Cbf-14 was designed by the addition of disulfide-bridged hendecapeptide (CWTKSIPPKPC) loop. Subsequently, the trypsin stability and antimicrobial and antibiofilm activities of this peptide were evaluated. The possible mechanisms underlying its mode of action were also clarified. The results showed that TICbf-14 exhibited elevated trypsin inhibitory activity and effectively mitigated lung histopathological damage in bacteria-infected mice by reducing the bacterial counts, further inhibiting the systemic dissemination of bacteria and host inflammation. Additionally, TICbf-14 significantly repressed bacterial swimming motility and notably inhibited biofilm formation. Considering the mode of action, we observed that TICbf-14 exhibited a potent membrane-disruptive mechanism, which was attributable to its destructive effect on ionic bridges between divalent cations and LPS of the bacterial membrane. Overall, TICbf-14, a bifunctional peptide with both antimicrobial and trypsin inhibitory activity, is highly likely to become an ideal candidate for drug development against bacteria.