Functionally important regions of glucose-6-phosphate dehydrogenase defined by the Saccharomyces cerevisiae enzyme and its differences from the mammalian and insect forms.
The primary structure of Saccharomyces cerevisiae glucose-6-phosphate dehydrogenase has been determined. It consists of 503 amino acid residues, with an acetyl-blocked N-terminus. The structure shows equally extensive differences from the corresponding mammalian and fruit fly enzymes (52% residues non-identical). Residues conserved in all the forms constitute about 40% of the structures and include two histidines. One of these (His200 in the numbering of the rat enzyme) occurs in a 10-residue conserved segment, including the reactive Lys204, probably related to substrate binding. Two segments with conserved Gly-Xaa-Xaa-Gly-Xaa-Xaa-Gly/Ala pattern constitute possibilities for the coenzyme-binding site. One is N-terminally located (positions 37-43) with two conserved arginine residues nearby (positions 56 and 71), of interest for phosphate binding. The other (positions 241-247) is in a middle region, with many residue identities, containing the conserved residues Arg256 and His264.
Persson
B
B
Department of Physiological Chemistry I, Karolinska Institutet, Stockholm, Sweden.
Jörnvall
H
H
Wood
I
I
Jeffery
J
J
D000595:Amino Acid Sequence; D000818:Animals; D003488:Cyanogen Bromide; D005954:Glucosephosphate Dehydrogenase / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D007313:Insecta / Q000201:enzymology*; D008322:Mammals; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000302:isolation & purification; D051381:Rats; D012441:Saccharomyces cerevisiae / Q000201:enzymology*; D012689:Sequence Homology, Nucleic Acid
D010446:Peptide Fragments; D005954:Glucosephosphate Dehydrogenase; D003488:Cyanogen Bromide