FIG. 4.
Relative activation of amino acids by PchE (open bars) and PchF (solid bars). ATP-PPi exchange activities were measured with proteinogenic amino acids (bars 1 to 20) and nonproteinogenic amino acids (bars 21 to 24) at a concentration of 1 mM. The highest exchange activity measured with l-cysteine was defined as 100%. The standard deviations of values in this assay were ≤20%. Bars 1, l-alanine; bars 2, l-arginine; bars 3, l-asparagine; bars 4, l-aspartate; bars 5, l-cysteine; bars 6, l-glutamate; bars 7, l-glutamine; bars 8, l-glycine; bars 9, l-histidine; bars 10, l-isoleucine; bars 11, l-leucine; bars 12, l-lysine; bars 13, l-methionine; bars 14, l-phenylalanine; bars 15, l-proline; bars 16, l-serine; bars 17, l-threonine; bars 18, l-tryptophan; bars 19, l-tyrosine; bars 20, l-valine; bars 21, l-homoserine; bars 22, l-2-aminobutyrate; bars 23, S-methyl-l-cysteine; bars 24, dl-allylglycine; bars 25, no amino acid added.