Roles of amino acid residues H66 and D326 in the creatine kinase activity and structural stability.


Creatine kinase (CK) is a key enzyme for cellular energy metabolism, catalyzing the reversible phosphoryl transfer from phosphocreatine to ADP in vertebrates. CK contains a pair of highly conserved amino acids (H66 and D326) which might play an important role in sustaining the compact structure of CK by linking its N- and C- terminal domains; however the mechanism is still unclear. In this study, spectroscopic, structural modeling and protein folding experiments suggested that D326A, H66P and H66P/D326A mutations led to disruption of the hydrogen bond between those two amino acid residues and form the partially unfolded state which made it easier to be inactivated and unfolded under environmental stresses, and more prone to form insoluble aggregates. The formation of insoluble aggregates would decrease levels of active CKs which may provide clues in CK deficiency disease. Moreover, these results indicated that the degree of synergism had closely relationship to the conformational changes of CK. Thus, our results provided clues for understanding the mechanism of amino acid residues outside the active site in regulating substrate synergism.

Submission Details

ID: 6xtdJCJH

Submitter: Shu-Ching Ou

Submission Date: Oct. 10, 2018, 3:30 p.m.

Version: 1

Publication Details
Wu QY;Wei F;Zhu YY;Tong YX;Cao J;Zhou P;Li ZY;Zeng LY;Li F;Wang XY;Xu KL,Int J Biol Macromol (2018) Roles of amino acid residues H66 and D326 in the creatine kinase activity and structural stability. PMID:28916380
Additional Information

Structure view and single mutant data analysis

Study data

No weblogo for data of varying length.
Colors: D E R H K S T N Q A V I L M F Y W C G P

Data Distribution

Studies with similar sequences (approximate matches)

Correlation with other assays (exact sequence matches)

Relevant UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
100.0 Creatine kinase M-type P06732 KCRM_HUMAN
96.3 Creatine kinase M-type P05123 KCRM_CANLF
97.1 Creatine kinase M-type Q5XLD3 KCRM_PIG
96.6 Creatine kinase M-type P07310 KCRM_MOUSE
96.6 Creatine kinase M-type P00564 KCRM_RAT
96.6 Creatine kinase M-type P00563 KCRM_RABIT
96.6 Creatine kinase M-type Q9XSC6 KCRM_BOVIN
90.3 Creatine kinase M-type P00565 KCRM_CHICK