Structural studies of human brain-type creatine kinase complexed with the ADP-Mg2+-NO3- -creatine transition-state analogue complex.
Creatine kinase is a member of the phosphagen kinase family, which catalyzes the reversible phosphoryl transfer reaction that occurs between ATP and creatine to produce ADP and phosphocreatine. Here, three structural aspects of human-brain-type-creatine-kinase (hBB-CK) were identified by X-ray crystallography: the ligand-free-form at 2.2A; the ADP-Mg2+, nitrate, and creatine complex (transition-state-analogue complex; TSAC); and the ADP-Mg2+-complex at 2.0A. The structures of ligand-bound hBB-CK revealed two different monomeric states in a single homodimer. One monomer is a closed form, either bound to TSAC or the ADP-Mg2+-complex, and the second monomer is an unliganded open form. These structural studies provide a detailed mechanism indicating that the binding of ADP-Mg2+ alone may trigger conformational changes in hBB-CK that were not observed with muscle-type-CK.
Bong
Seoung Min
SM
Division of Biotechnology, College of Life Sciences, Korea University, Seoul 136-713, Republic of Korea.
Moon
Jin Ho
JH
Nam
Ki Hyun
KH
Lee
Ki Seog
KS
Chi
Young Min
YM
Hwang
Kwang Yeon
KY
D000244:Adenosine Diphosphate / Q000737:chemistry*; D052276:Creatine Kinase, BB Form / Q000737:chemistry*; D018360:Crystallography, X-Ray; D006801:Humans; D008274:Magnesium / Q000737:chemistry*; D009589:Nitrogen Oxides / Q000737:chemistry*; D011487:Protein Conformation; D017510:Protein Folding
D009589:Nitrogen Oxides; C031701:nitrogen trioxide; D000244:Adenosine Diphosphate; D052276:Creatine Kinase, BB Form; D008274:Magnesium