Fig. 4.

Frequency distribution of amino acids surrounding lysines in human histone and nonhistone proteins. Frequency of amino acids (y axis) spanning positions −6 to +6 (x axis) in validated acetylated lysines in histone proteins (23 lysines) (A), validated acetylated lysines within proteins in literature (73 lysines) (B), validated lysines in the pan-acetyl IP substrates (51 lysines) (C), not observed as acetylated lysines in histones (33 lysines) (D), and not observed as acetylated lysines in proteins as reported in literature and not observed as acetylated lysines in pan-acetyl IP substrates (3,493 lysines) (E). Residues in green: basic; red: hydrophobic; pink: small; blue: S/T; black: all other residues. Underlined red K: lysine that has been validated experimentally as acetylated; underlined green K: lysine that has not been experimentally observed as acetylated. X denotes that no amino acid was present in that position. Tick marks represent residues described in text.