Mechanism of phosphoryl transfer catalyzed by shikimate kinase from Mycobacterium tuberculosis.
The structural mechanism of the catalytic functioning of shikimate kinase from Mycobacterium tuberculosis was investigated on the basis of a series of high-resolution crystal structures corresponding to individual steps in the enzymatic reaction. The catalytic turnover of shikimate and ATP into the products shikimate-3-phosphate and ADP, followed by release of ADP, was studied in the crystalline environment. Based on a comparison of the structural states before initiation of the reaction and immediately after the catalytic step, we derived a structural model of the transition state that suggests that phosphoryl transfer proceeds with inversion by an in-line associative mechanism. The random sequential binding of shikimate and nucleotides is associated with domain movements. We identified a synergic mechanism by which binding of the first substrate may enhance the affinity for the second substrate.
Hartmann
Marcus D
MD
Max Planck Unit for Structural Molecular Biology, MPG-ASMB c/o DESY, Notkestrasse 85, 22603 Hamburg, Germany.
Bourenkov
Gleb P
GP
Oberschall
Attila
A
Strizhov
Nicolai
N
Bartunik
Hans D
HD
D000244:Adenosine Diphosphate / Q000737:chemistry*; D001426:Bacterial Proteins / Q000737:chemistry*; D001665:Binding Sites; D002384:Catalysis; D003460:Crystallization; D018360:Crystallography, X-Ray; D008958:Models, Molecular; D009169:Mycobacterium tuberculosis / Q000201:enzymology*; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D012765:Shikimic Acid / Q000031:analogs & derivatives* / Q000737:chemistry; D013379:Substrate Specificity
D001426:Bacterial Proteins; D012765:Shikimic Acid; D000244:Adenosine Diphosphate; C042786:shikimic acid-3-phosphate; D017853:Phosphotransferases (Alcohol Group Acceptor); C022642:shikimate kinase