Biochemical and molecular characterization of a new sporadic glucose-6-phosphate dehydrogenase variant described in Italy: G6PD Modena.
A new glucose-6-phosphate dehydrogenase variant detected in an Italian man from the Po delta is described and designated as G6PD Modena. Biochemical characterization of the variant enzyme revealed an activity 21% of normal, a slow electrophoretic mobility, increased Km value for NADP, decreased Km value for G6P and a complete absence of NADPH inhibition, which could account for the apparently nonhaemolytic feature of this variant. The cloning and sequencing of the G6PD Modena allele showed a G-->C transition at nucleotide 844 in exon VIII causing a Asp-->His amino acid substitution. On the basis of biochemical characterization, G6PD Modena is classified as a genuine variant but it has the same mutation as G6PD Seattle-like.
Cappellini
M D
MD
Istituto di Medicina Interna e Fisiopatologia Medica, Ospedale Maggiore Policlinico, Milano, Italy.
Sampietro
M
M
Toniolo
D
D
Carandina
G
G
Pittalis
S
S
Martinez di Montemuros
F
F
Tavazzi
D
D
Fiorelli
G
G
D000328:Adult; D001483:Base Sequence; D004588:Electrophoresis, Cellulose Acetate; D005954:Glucosephosphate Dehydrogenase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D005955:Glucosephosphate Dehydrogenase Deficiency / Q000201:enzymology* / Q000235:genetics; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D008969:Molecular Sequence Data; D009154:Mutation
D005954:Glucosephosphate Dehydrogenase