Substrate specificity of microbial transglutaminase as revealed by three-dimensional docking simulation and mutagenesis.
Transglutaminases (TGases) are used in fields such as food and pharmaceuticals. Unlike other TGases, microbial transglutaminase (MTG) activity is Ca(2+)-independent, broadening its application. Here, a three-dimensional docking model of MTG binding to a peptide substrate, CBZ-Gln-Gly, was simulated. The data reveal CBZ-Gln-Gly to be stretched along the MTG active site cleft with hydrophobic and/or aromatic residues interacting directly with the substrate. Moreover, an oxyanion binding site for TGase activity may be constructed from the amide groups of Cys64 and/or Val65. Alanine mutagenesis verified the simulated binding region and indicated that large molecules can be widely recognized on the MTG cleft.
Institute of Life Sciences, Ajinomoto Co., Inc, 1-1 Suzuki-cho, Kawasaki-ku, Kawasaki-shi 210-8681, Japan.
Uno
U
Tagami
Nobuhisa
N
Shimba
Mina
M
Nakamura
Kei-Ichi
K
Yokoyama
Ei-Ichiro
E
Suzuki
Takatsugu
T
Hirokawa
D008958:Models, Molecular; D056004:Molecular Dynamics Simulation; D016297:Mutagenesis, Site-Directed; D013379:Substrate Specificity; D000637:Transaminases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
D000637:Transaminases