A peptide fragment derived from the T-cell antigen receptor protein alpha-chain adopts beta-sheet structure and shows potent antimicrobial activity

作者：Zhang Genghui; Lin Xiaoyan; Long Yi; Wang Yanqiang; Zhang Yueheng; Mi Huaifeng; Yan Husheng^*

来源：Peptides, 2009, 30(4): 647-653.

DOI：10.1016/j.peptides.2008.12.002

• Antibiotic
• Antimicrobial peptide
• Peptide
• beta-Sheet
• T-cell antigen receptor

A 9-residue peptide, CP-1 (GLRILLLKV-NH(2)), is synthesized by solid-phase synthesis method. CP-1 is a C-terminal amidated derivative of a hydrophobic transmembrane segment (CP) of the T-cell antigen receptor (TCR) alpha-chain. CP-1 shows broad-spectrum antimicrobial activities against Gram-positive and Gram-negative bacteria with the minimal inhibitory concentration (MIC) values between 3 and 77 mu M. Circular dichroism (CD) spectral data shows that CP-1 adopts a well-defined beta-sheet structure in membrane-mimicking environments. CP-1 kills E coli without lysing the cell membrane or forming transmembrane pores. However, CP-1 can penetrate the bacterial cell membranes and accumulate in the cytoplasm in both Gram-positive S. aureus and Gram-negative E. coli. Moreover CP-1 shows binding affinity for plasmid DNA. These results indicate that the killing mechanism of CP-1 likely involves the penetration into the cytoplasm and binding to intracellular components such as DNA.

• 出版日期2009-4
• 单位南开大学