Discovery of sarcosine dimethylglycine methyltransferase from Galdieria sulphuraria.

TitleDiscovery of sarcosine dimethylglycine methyltransferase from Galdieria sulphuraria.
Publication TypeJournal Article
Year of Publication2009
AuthorsMcCoy JG, Bailey LJ, Ng YHan, Bingman CA, Wrobel R, Weber APM, Fox BG, Phillips GN
JournalProteins
Volume74
Issue2
Pagination368-77
Date Published2009 Feb 1
ISSN1097-0134
KeywordsAlgal Proteins, Crystallography, X-Ray, Enzyme Stability, Kinetics, Methyltransferases, Protein Folding, Protein Structure, Tertiary, Rhodophyta, Sarcosine, Sequence Alignment, Substrate Specificity, Temperature
Abstract

An enzyme with sarcosine dimethylglycine methyltransferase (SDMT) activity has been identified in the thermophilic eukaryote, Galdieria sulphuraria. The crystal structure of the enzyme, solved to a resolution of 1.95 A, revealed a fold highly similar to that of mycolic acid synthases. The kcat and apparent K(M) values were 64.3 min(-1) and 2.0 mM for sarcosine and 85.6 min(-1) and 2.8 mM for dimethylglycine, respectively. Apparent K(M) values of S-adenosylmethionine were 144 and 150 microM for sarcosine and dimethylglycine, respectively, and the enzyme melting temperature was 61.1 degrees C. Modeling of cofactor binding in the active site based on the structure of methoxy mycolic acid synthase 2 revealed a number of conserved interactions within the active site.

DOI10.1002/prot.22147
Alternate JournalProteins
PubMed ID18623062
PubMed Central IDPMC2742680
Grant List5T32HG002760 / HG / NHGRI NIH HHS / United States
U54 GM074901 / GM / NIGMS NIH HHS / United States
U54 GM074901-05 / GM / NIGMS NIH HHS / United States
Y1-CO-1020 / CO / NCI NIH HHS / United States
Y1-GM-1104 / GM / NIGMS NIH HHS / United States