Biomaterial Database

Features of structural zinc in mammalian alcohol dehydrogenase. Site-directed mutagenesis of the zinc ligands. 1994

J Jeloková, and C Karlsson, and M Estonius, and H Jörnvall, and J O Höög

Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.

All four cysteine ligands to the structural zinc atom of human class-I and class-III alcohol dehydrogenase have been exchanged by site-directed mutagenesis in order to study the importance of the metal in the mammalian enzymes. The cysteine residues were replaced with Ala and Ser, residues that are not able to ligand zinc. All mutations resulted in inactive, unstable enzymes, in contrast to the non-mutated human alcohol dehydrogenases that are easily isolated. Northern-blot analysis revealed the presence of the expected mRNAs from expression plasmids constructed with the different mutated and non-mutated alcohol dehydrogenases, and Western-blot analysis gave faint signals for the mutated recombinant proteins from crude extracts. This verifies that the plasmid constructs are correct, but that the translated, mutated proteins lacking the zinc-stabilized local fold, are subject to rapid degradation. Hence, the results directly illustrate the importance of the structural zinc atom in mammalian alcohol dehydrogenase and confirm it as a component with 'structural' properties. The results are compatible with those from sensitivities to proteases and from the structures of other proteins within the super-family, indicating that the structural role of the zinc atom may involve conservation of interfaces regulating the enzyme quaternary structure.

UI	MeSH Term	Description	Entries
D008024	Ligands	A molecule that binds to another molecule, used especially to refer to a small molecule that binds specifically to a larger molecule, e.g., an antigen binding to an antibody, a hormone or neurotransmitter binding to a receptor, or a substrate or allosteric effector binding to an enzyme. Ligands are also molecules that donate or accept a pair of electrons to form a coordinate covalent bond with the central metal atom of a coordination complex. (From Dorland, 27th ed)	Ligand
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D011487	Protein Conformation	The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).	Conformation, Protein,Conformations, Protein,Protein Conformations
D011994	Recombinant Proteins	Proteins prepared by recombinant DNA technology.	Biosynthetic Protein,Biosynthetic Proteins,DNA Recombinant Proteins,Recombinant Protein,Proteins, Biosynthetic,Proteins, Recombinant DNA,DNA Proteins, Recombinant,Protein, Biosynthetic,Protein, Recombinant,Proteins, DNA Recombinant,Proteins, Recombinant,Recombinant DNA Proteins,Recombinant Proteins, DNA
D003001	Cloning, Molecular	The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.	Molecular Cloning
D003545	Cysteine	A thiol-containing non-essential amino acid that is oxidized to form CYSTINE.	Cysteine Hydrochloride,Half-Cystine,L-Cysteine,Zinc Cysteinate,Half Cystine,L Cysteine
D004926	Escherichia coli	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.	Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000426	Alcohol Dehydrogenase	A zinc-containing enzyme which oxidizes primary and secondary alcohols or hemiacetals in the presence of NAD. In alcoholic fermentation, it catalyzes the final step of reducing an aldehyde to an alcohol in the presence of NADH and hydrogen.	Alcohol Dehydrogenase (NAD+),Alcohol Dehydrogenase I,Alcohol Dehydrogenase II,Alcohol-NAD+ Oxidoreductase,Yeast Alcohol Dehydrogenase,Alcohol Dehydrogenase, Yeast,Alcohol NAD+ Oxidoreductase,Dehydrogenase, Alcohol,Dehydrogenase, Yeast Alcohol,Oxidoreductase, Alcohol-NAD+
D000595	Amino Acid Sequence	The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.	Protein Structure, Primary,Amino Acid Sequences,Sequence, Amino Acid,Sequences, Amino Acid,Primary Protein Structure,Primary Protein Structures,Protein Structures, Primary,Structure, Primary Protein,Structures, Primary Protein