景东湍蛙抗菌肽jindongenin-1d的分析和活性测定

新型抗菌肽研究有助于解决细菌对抗生素的耐药性问题。本研究用SMART技术构建了景东湍蛙Amolops jingdongensis皮肤的全长cDNA文库。通过单克隆和测序获得一个抗菌肽cDNA序列,序列比对结果表明其属于jindongenin-1家族,命名为jindongenin-1d。其cDNA序列全长321bp,编码含66个氨基酸残基的多肽。该多肽包括1个信号肽和1个前肽序列。成熟jindongenin-1d多肽包含24个氨基酸残基,理论分子量为2 709.38,等电点为9.24。对人工合成的jindongenin-1d蛋白进行了抗菌和溶血活性分析,结果表明jindongenin-1d对所选的革兰氏阴性菌、革兰氏阳性菌和真菌均有显著抑制作用,同时有弱溶血活性。本研究结果有助于进一步了解两栖动物皮肤分泌物活性物质的多态性和新型抗感染药物的设计。

Analysis and bioactivities of antimicrobial peptide jindongenin-1d from Amolops jingdongensis

The study of new natural antimicrobial peptides (AMPs) can help solving the serious problem of bacterial resistance to currently used antibiotics.A full length cDNA library of Amolops jingdongensis skin was constructed with the SMART technique.An antimicrobial peptide cDNA sequence was obtained by screening and sequencing.Sequence aligning results showed that the sequence belonged to the jindongenin-1 family,designated as jindongenin1d.This cDNA sequence with a full length of 321 bp encodes a polypeptide of 66 amino acid residues including a signal peptide and a propeptide.The mature peptide contains 24 amino acid residues with a theoretical molecular mass of 2 709.38 and an isoelectric point of 9.24.The antibacterial activity and hemolytic activity of the synthetic jindongenin-1d protein were analyzed.The results showed that jindongenin-1d exhibited significant inhibiting activity against the selected Gram-negative bacteria,Gram-positive bacteria and fungi and weak hemolytic activity.These findings provide helpful insight that will be useful in the design of anti-infective peptide agents.