A Study Of Functional Peptides From Skins And Its Secretions Of Hylarana Taipehensis, Amolops Lifanensis, And Amolops Granulosus

Functional peptides discovered from amphibians skins and secretions varies not only in structures, but also in bioactivities such as microbial inhibition, antioxidation, antiallergy, wound healing, and etcetra. Recent years, drawing great attention, amphibians functional peptides has become a popular topic in medical and therapeutic fields for their superiorities of high effectiveness, low immunogenicity and low cytotoxicity.In this study, 14 peptides were extracted from the skin secretions of Hylarana taipehensis, Amolops lifanensis, and Amolops granulosus by RP-HPLC. The full length skin c DNA libraries of the three species were established respectively and 46 peptide precursor c DNA sequences, encoding 37 mature peptides, were confirmed by screening the positive clones. These peptides belong to 12 different families according to Blast alignment. Among all these peptides, taipehensis-1TP1(TLIWEFYHQILDEYNKENKG) and taipehensis-2TP1(CLMARPNYRCKIFKQC) are two novel peptides with no previous report on either of thire structures or bioactivities. An overall peptidomic analysis and identification of the expression of peptides cloned from frog skins were conducted by an LC-MS/MS method.There were 8 peptides showed antioxidant activity and 6 of them possess both antioxidant and antimicrobial activity, meanwhile most of the rest are antimicrobial peptides. The two novel peptides taipehensin-1TP1 and taipehensin-2TP1 showed distinct ABTS·+and/or DPPH· free radical scavenging capacity while no hemolytic activity were detected in a concentration not more than 100 μM. So these two peptides have a great potential to be used in therapeutic methods or food processing industry.This research discovered a series of peptides with different bioactivities and provides a theoretical contribution to studies on the structures, functions and mechanisms of antimicrobial and antioxidant peptides. Meanwhile, this study provides a reference for the application of amphibians functional peptides.