Molecular Cloning of Two Novel Temporins From Lithobates catesbeianus and Studying of Their Antimicrobial Mechanisms / 生物化学与生物物理进展

ABSTRACT

Temporins are a kind of small,hydrophobic and C-terminus amidated antimicrobial peptides from Rana species.They are effective against bacteria,fungi,yeast,protozoa and viruses.Two novel temporins named as temporin-La(LLRHWKILEKYLanifc) and temporin-Lb(LFRHVVKIFEK.Ylamid.) were cloned from Lithobates catesbeianus.Synthetic peptides of temporin-La and temporin-Lb showed strong antimicrobial activities against bacteria tested,especially Gram-positive bacteria.Besides,temporin-La showed no haemolytic activity to rabbit erythrocytes at the concentration of 250 mg/L while temporin-Lb showed weak haemolytic activity(LC50≈ 230 μmol/L).Transmission electron microscopy showed that temporin-La and temporin-Lb induced different effects on bacterial structure of Staphylococcus aureus.