Our analysis also yielded a series of amino acid dyads that showed preference for α‐helix conformation. It was shown that the amino acid pair preference for α‐helix had a unique pattern and this pattern was not always predictable by assuming proportional contributions from the individual propensity values of the amino acids. This method produced an enhanced statistical significance scale that allowed us to explore the positional preference of amino acids for α‐helical conformations. Sequence patterns favoring helical conformation were derived from a neighbor‐dependent sequence analysis of proteins, which calculated the effect of neighboring amino acid type on the propensity of residues for adopting a particular secondary structure in proteins.

Trp was the strongest helix conformer in short helices. Pro and Trp had a significantly higher propensity for helical conformation in short helices than in medium and long helices. It was found that some amino acids had differential propensity values for adopting helical conformation in short, medium and long α‐helices. α‐Helices were extracted from the Protein Data Bank (PDB) and were divided into groups according to their sizes. This paper reports an extensive sequence analysis of the α‐helices of proteins.

Bias fx acid pro 8