tailieunhanh - Báo cáo khoa học: Novel cathelicidin-derived antimicrobial peptides from Equus asinus

In the present study, EA-CATH1 and EA-CATH2 were identified from a constructed lung cDNA library of donkey (Equus asinus) as members of cathelicidin-derived antimicrobial peptides, using a nested PCR-based cloning strategy. Composed of 25 and 26 residues, respectively, EA-CATH1 and EA-CATH2 are smaller than most other cathelicidins and have no sequence homology to other cathelicidins identified to date. | Novel cathelicidin-derived antimicrobial peptides from Equus asinus Zekuan Lu1 Yipeng Wang2 3 Lei Zhai1 Qiaolin Che3 Hui Wang1 Shuyuan Du1 Duo Wang1 Feifei Feng1 2 Jingze Liu1 Ren Lai3 and Haining Yu1 2 1 College of Life Sciences Hebei Normal university Shijiazhuang China 2 Schoolof Life Science and Biotechnology Dalian University of Technology China 3 Key Laboratory of AnimalModels and Human Disease Mechanisms Kunming Institute of Zoology Chinese Academy of Sciences Kunming Yunnan China Keywords cathelicidin Equus asinus function gene cloning peptide identification Correspondence R. Lai Key Laboratory of AnimalModels and Human Disease Mechanisms Kunming Institute of Zoology Chinese Academy of Sciences Kunming 650223 Yunnan China Fax Tel 86 871 5196202 E-mail rlai@ H. Yu College of Life Sciences Hebei NormalUniversity Shijiazhuang Hebei 050016 China Fax Tel 86 311 86268842 E-mail yuhaining@ These authors contributed equally to this work Received 11 January 2010 revised 10 March 2010 accepted 15 March 2010 doi In the present study EA-CATH1 and EA-CATH2 were identified from a constructed lung cDNA library of donkey Equus asinus as members of cathelicidin-derived antimicrobial peptides using a nested PCR-based cloning strategy. Composed of 25 and 26 residues respectively EA-CATH1 and EA-CATH2 are smaller than most other cathelicidins and have no sequence homology to other cathelicidins identified to date. Chemically synthesized EA-CATH1 exerted potent antimicrobial activity against most of the 32 strains of bacteria and fungi tested especially the clinically isolated drug-resistant strains and minimal inhibitory concentration values against Gram-positive bacteria were mostly in the range of ig-mL-1. EA-CATH1 showed an extraordinary serum stability and no haemolytic activity against human erythrocytes in a dose up to 20 ig-mL-1. CD spectra showed that EA-CATH1 mainly adopts an a-helical conformation in a