A bioactivity peptide QUB2852 from the frog skin secretion of pelophylax nigromaculata

Abstract

Due to the resistance of antibiotics, antimicrobial peptides (AMPs) become research hotspot. Majority of AMPs can disrupt the cell membrane of microorganisms, leading to the death of microorganisms. In this study, the AMP QUB-2852 was identified from the skin secretion of pelophylax nigromaculata through cloning of its precursor-encoding cDNA from a skin secretion-derived cDNA library by using a 3'-rapid amplification of cDNA ends (RACE) “shotgun” strategy. Subsequently, the mature peptide sequence was confirmed through online alignment analysis. Biological assessment using the chemically synthesised replicates of QUB-2852 showed that it possessed potent antimicrobial activity against Gram-positive Bacteria Staphylococcus aureus at 32 μmol/l However, QUB-2852 showed relatively weaker inhibitory activity against the Gram-negative bacterial and yeast. In addition, QUB-2852 exhibited anti-proliferative activity against human cancer cell line U251MG. The haemolysis effect was relatively low, which was less than 20% at the concentration up to 512 μmol/l. These characteristics make QUB-2852 a promising antimicrobial agent that warrants further investigations. In particular, its structure-activity relationship would provide valuable insights into drug design for novel antimicrobial and/or anti-cancer agents development.

Date of Award	Jul 2018
Original language	English
Awarding Institution	Queen's University Belfast
Supervisor	Yuxin Wu (Supervisor), Tianbao Chen (Supervisor), Christopher Shaw (Supervisor), Mei Zhou (Supervisor) & Lei Wang (Supervisor)