Molecular cloning, expression, purification, and functional characterization of palustrin-2CE, an antimicrobial peptide of Rana chensinensis.
Antimicrobial peptides are effector molecules of the innate immunity of amphibians. Here, one antimicrobial peptide cDNA precursor, prepropalustrin-2CE3, from the tadpole of the Chinese brown frog Rana chensinensis was cloned. The coding sequence corresponding to the mature palustrin-2CE peptide was subcloned into pGEX-6p-1. The soluble GST-palustrin-2CE fusion protein was successfully expressed in the BL21(DE3)pLysS strain at 16 °C, and the proportion of the fusion protein reached 35%-39% of the total cellular protein. After removal of the GST-fusion tag, the purity of the palustrin-2CE obtained by Sephadex G50 chromatography was about 97%. Moreover, the purified palustrin-2CE displayed obviously inhibitory activities against the sensitive bacteria Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, and Escherichia coli, and multi-drug resistant S. aureus and E. coli. These findings suggest that the tadpole of the Chinese brown frog is a unique source of antimicrobial peptides and indicates the therapeutic potential of the palustrin-2CE peptide.
College of Life Sciences, Shaanxi Normal University, Xi'an, China.
Yan
Y
Sun
Qian
Q
Li
Zhi
Z
Li
Yuan
Y
Zhang
Jie
J
Zhao
Lin
L
Wang
D000595:Amino Acid Sequence; D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects / Q000254:growth & development; D001483:Base Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D015870:Gene Expression; D007814:Larva / Q000235:genetics; D008969:Molecular Sequence Data; D011898:Ranidae / Q000235:genetics*
D023181:Antimicrobial Cationic Peptides; D018076:DNA, Complementary