Structure‐guided RP‐HPLC chromatography of diastereomeric α‐helical peptide analogs substituted with single amino acid stereoisomers. (11th October 2013)

• Record Type: Journal Article
• Authors: Huang, YiBing; Pan, Ling; Zhao, LianJing; Mant, Colin T.; Hodges, Robert S.; Chen, Yuxin
• Is Part Of: Biomedical chromatography. Volume 28:Number 4(2014:Apr.)
• Page Start: 511
• Page End: 517
• Publication Date: 2013-10-11
• Subjects: Chromatographic analysis -- Periodicals; Biology -- Periodicals; Medicine -- Periodicals; Biology -- Periodicals; Chromatography -- methods -- Periodicals; Medicine -- Periodicals; 543.089
• DOI: 10.1002/bmc.3061
• Languages: English
• ISSNs: 0269-3879

Abstract

<abstract abstract-type="main"> <title>ABSTRACT</title> <p>An <italic>α</italic>‐helical model peptide (Ac‐EAEKAAKE‐X‐EKAAKEAEK‐amide) was used as a template to examine the efficacy of conventional reversed‐phase high‐performance liquid chromatography (RP‐HPLC) in separating peptide analogs with single substitutions (at position X) of diasteromeric amino acids Ile, <italic>allo</italic>‐Ile, <sc>d</sc>‐Ile and <sc>d</sc>‐<italic>allo</italic>‐Ile. We compared differences in peptide retention behavior on a C₈ column and a C₁₈ column at different temperatures. We demonstrated how subtle differences in peptide secondary structure affected by the different substitutions of amino acids with identical overall hydrophobicity enabled effective resolution of these peptide analogs. We also demonstrated the ability of RP‐HPLC to separate Ile‐ and <italic>allo</italic>‐Ile‐substituted analogs of a 26‐residue <italic>α</italic>‐helical antimicrobial peptide (AMP), with the substitution site towards the C‐terminus of the <italic>α</italic>‐helix. These peptides show different values of antibacterial activity and hemolytic activity, and different selectivity against bacteria and human cells. Our results underline the ability of RP‐HPLC to resolve even difficult diasteromeric peptide mixtures as well as its value in monitoring very subtle hydrophobicity changes in <italic>de novo</italic>‐designed AMP. Copyright © 2013 John Wiley &amp; Sons, Ltd.</p> </abstract>