Open AccessStructure of glyceraldehyde‐3‐phosphate dehydrogenase from the archaeal hyperthermophile Methanocaldococcus jannaschii
Author(s) -
Malay Ali D.,
Bessho Yoshitaka,
Ellis Mark J.,
Antonyuk Svetlana V.,
Strange Richard W.,
Hasnain S. Samar,
Shinkai Akeo,
Padmanabhan Balasundaram,
Yokoyama Shigeyuki
Publication year - 2009
Publication title -
acta crystallographica section f
Language(s) - English
Resource type - Journals
ISSN - 1744-3091
DOI - 10.1107/s1744309109047046
Subject(s) - glyceraldehyde 3 phosphate dehydrogenase , hyperthermophile , dehydrogenase , cofactor , biochemistry , active site , nucleotide , binding site , biology , glyceraldehyde , chemistry , enzyme , archaea , gene
The X‐ray crystal structure of glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH) from the hyperthermophilic archaeon Methanocaldococcus jannaschii (Mj‐GAPDH) was determined to 1.81 Å resolution. The crystal belonged to space group C 222 1 , with unit‐cell parameters a = 83.4, b = 152.0, c = 118.6 Å. The structure was solved by molecular replacement and was refined to a final R factor of 17.1% ( R free = 19.8%). The final structure included the cofactor NADP + at the nucleotide‐binding site and featured unoccupied inorganic and substrate phosphate‐binding sites. A comparison with GAPDH structures from mesophilic sources suggested that Mj‐GAPDH is stabilized by extensive electrostatic interactions between the C‐terminal α‐helices and various distal loop regions, which are likely to contribute to thermal stability. The key phosphate‐binding residues in the active site of Mj‐GAPDH are conserved in other archaeal GAPDH proteins. These residues undergo a conformational shift in response to occupancy of the inorganic phosphate site.