Open AccessStructural Studies of Human‐Liver Alcohol‐Dehydrogenase Isoenzymes
Author(s) -
BERGER Denis,
BERGER Marianne,
WARTBURG JeanPierre
Publication year - 1974
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1974.tb03890.x
Subject(s) - protein subunit , isozyme , biochemistry , alcohol dehydrogenase , enzyme , biology , homology (biology) , microbiology and biotechnology , chemistry , amino acid , gene
1 Alcohol dehydrogenase isoenzymes BE were isolated from human livers of both “normal” and “atypical” phenotypes [1]. Their pH‐rate profiles, their behaviour on CM‐cellulose and the number of hybrids formed with horse subunit A show that the “atypical” isoenzymes contain subunits B 1 and B 2 the “normal” one only subunit B 1 . These results indicate that most “atypical” individuals genetically represent heterozygotes. 2 A high degree of homology between horse subunit A and human subunits B is found. However, the human isoenzymes have a molecular weight of 87000 and contain about 410 amino acid residues, 6 tyrosines and 3 tryptophans per subunit. 3 The sequence of one tryptic peptide from subunit B 1 is Phe‐Ala‐Lys and is altered to Phe‐Pro‐Lys in the subunit B 2 . This substituted residue is located in a region which corresponds to the coenzyme‐binding site of the horse enzyme.