Depth of side-chain pocket in the S2 subsite of dipeptidyl peptidase IV.
Kinetic studies of pig kidney dipeptidyl peptidase IV (dipeptidyl-peptide hydrolase, EC 3.4.14.5) were carried out using substrates possessing a side-chain of different length at the P2 position (or amino-terminal position in this case) such as Lys-, Arg-, Phe-, Met-, Ser-, His-, Glu- and Gly-Pro-pNA. The hydrolytic coefficient (Kcat/Km) has determined in the order Met- greater than Glu- greater than Ser- greater than His- greater than Phe- greater than Lys- greater than Gly- greater than Arg-, indicating a gradual increase with elongation of the side-chain from 0.03 to 0.60 nm followed by a decline when side-chain length approached 0.70 nm. Thus, the most probable depth of the side-chain pocket at the S2 subsite of the enzyme is proposed to be 0.50-0.60nm.
Harada
M
M
Fukasawa
K
K
Hiraoka
B Y
BY
Mogi
M
M
Barth
A
A
Neubert
K
K
D000818:Animals; D001665:Binding Sites; D055598:Chemical Phenomena; D002621:Chemistry; D018819:Dipeptidyl Peptidase 4; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases / Q000378:metabolism*; D010450:Endopeptidases / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007668:Kidney / Q000201:enzymology; D007700:Kinetics; D013329:Structure-Activity Relationship; D013379:Substrate Specificity; D013552:Swine
D010450:Endopeptidases; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases; D018819:Dipeptidyl Peptidase 4