indole decreases the absorbance obtainable at 500 nm for amino acids with small hydrophobic side chains ( l-ala , gly ) , increases this absorbance for amino acids with small polar side chains ( beta-cyano-l-alanine ) , and does not change the spectra of tryptophanase complexes with amino acids with bulky side chains , i.e . amino acids whose binding affinities are unaffected by indole .
C0017890
gly
C0002520
amino acids