초록 ▼

The present invention relates to methods for immunoassay of analytes employing mutant glucose-6-phosphate dehydrogenase (G6PDH) enzymes as labels. In particular, the invention relates to the use of conjugates of an analyte or analyte analog and a mutant NAD.sup.+ dependent G6PDH differing from any p

The present invention relates to methods for immunoassay of analytes employing mutant glucose-6-phosphate dehydrogenase (G6PDH) enzymes as labels. In particular, the invention relates to the use of conjugates of an analyte or analyte analog and a mutant NAD.sup.+ dependent G6PDH differing from any precursor G6PDH by the deletion, substitution, or insertion, or any combination thereof of at least one amino acid per subunit. The invention also involves the construction of several mutations in precursor glucose-6-phosphate dehydrogenase (G6PDH) enzymes. Typically, the mutations involve deletion or substitution of one or more lysine residues, or introduction of one or more cysteine residues by insertion of cysteine to precursor G6PDH or substitution of precursor G6PDH amino acids residues with cysteine. The present invention also relates to conjugates of the subject enzymes and specific binding pair members, kits useful in performing the methods of the invention, cell lines producing the subject enzymes, DNA sequences encoding the subject enzymes, and vectors containing DNA encoding the subject enzymes and designed to allow a host cell to produce the subject enzymes.

대표청구항 ▼

[ What is claimed is:] [1.] A mutant glucose-6-phosphate dehydrogenase (G6PDH) that is the expression product of a mutated DNA sequence encoding a G6PDH, the mutant G6PDH being derived from a precursor G6PDH from a Leuconostoc organism by the deletion of, or substitution for, at least two lysines pe

[ What is claimed is:] [1.] A mutant glucose-6-phosphate dehydrogenase (G6PDH) that is the expression product of a mutated DNA sequence encoding a G6PDH, the mutant G6PDH being derived from a precursor G6PDH from a Leuconostoc organism by the deletion of, or substitution for, at least two lysines per subunit, or the introduction of at least one cysteine per subunit, by insertion of said cysteine or substitution of said cysteine for an amino acid residue other than cysteine in said precursor G6PDH wherein said mutant G6PDH has the ability to catalyze the oxidation of D-glucose-6-phosphate to D-glucono-.delta.-lactone-6-phosphate by utilizing either NAD.sup.+ or NADP.sup.+.