Homology similarity analysis of sequences of lactoferricin and its derivatives.

A new method, homology similarity analysis (HSA), was developed to investigate homology pattern similarities of selected segments within sequences of peptides. This new approach facilitated elucidation of the structure-function relationships of lactoferricin derivatives. Helix propensity of positions 4-9 in the lactoferricin sequence was the most important in determining the antimicrobial activity of lactoferricin against Escherichia coli, followed by cationic charge pattern at positions 4-9 and 1-3. The pattern similarity of segments within sequences could be a useful tool for representing the distribution attributes of amino acid residue properties to the structure-function relationships of proteins and peptides, especially when used in conjunction with principal component similarity analysis followed by the regression version of artificial neural networks.