Biomaterial Database

Glycine and taurine conjugation of bile acids by a single enzyme. Molecular cloning and expression of human liver bile acid CoA:amino acid N-acyltransferase. 1994

C N Falany, and M R Johnson, and S Barnes, and R B Diasio

Department of Pharmacology, University of Alabama at Birmingham 35294.

In order to establish whether a single enzyme in human liver was capable of conjugating bile acids with both glycine and taurine, a cDNA encoding human liver bile acid-CoA:amino acid N-acyltransferase (hBAT) has been isolated and characterized. A specific immunoaffinity-purified rabbit anti-hBAT polyclonal antibody was used to screen a lambda Zap XR human liver cDNA library resulting in the isolation of two unique clones. hBAT8 and hBAT9 (1669 and 1491 base pairs in length, respectively) were isolated following screening of 4 x 10(5) clones of the cDNA library. Restriction mapping and sequence analysis demonstrated that the cDNAs were identical except hBAT8 contained an additional 178 bases of 5' sequence; hBAT8 was completely sequenced, characterized, and used for all subsequent studies. hBAT8 consisted of a 184-nucleotide 5'-nontranslated region, an open reading frame of 1,254 bases predicting a protein of 418 amino acids with a molecular mass of 46,296 Da, and a 3'-nontranslated region of 209 nucleotides followed by a poly(A)+ tail. The identity of the cDNA was confirmed by the following findings: 1) the open reading frame began with an ATG codon and was followed by a nucleotide sequence which, when translated, corresponded exactly to the first 17 NH2-terminal amino acids of purified human liver BAT; 2) cytosol of Escherichia coli XL1-Blue cells transfected with hBAT8 subcloned into an expression vector, pKK233-2, demonstrated significant enzymatic activity for the conjugation of both taurine and glycine with cholic acid; 3) bacterial expression of hBAT8 generated a protein that comigrated with hBAT from human liver during SDS-polyacrylamide gel electrophoresis and cross-reacted with a specific polyclonal rabbit anti-hBAT antibody during immunoblot analysis; 4) kinetic characteristics of the expressed enzyme were very similar to those reported for purified liver BAT. These data demonstrate that a single cDNA is present in human liver which codes for a protein capable of catalyzing the conjugation of cholic acid with both glycine and taurine.

UI	MeSH Term	Description	Entries
D008099	Liver	A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.	Livers
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
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
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
D005998	Glycine	A non-essential amino acid. It is found primarily in gelatin and silk fibroin and used therapeutically as a nutrient. It is also a fast inhibitory neurotransmitter.	Aminoacetic Acid,Glycine, Monopotassium Salt,Glycine Carbonate (1:1), Monosodium Salt,Glycine Carbonate (2:1), Monolithium Salt,Glycine Carbonate (2:1), Monopotassium Salt,Glycine Carbonate (2:1), Monosodium Salt,Glycine Hydrochloride,Glycine Hydrochloride (2:1),Glycine Phosphate,Glycine Phosphate (1:1),Glycine Sulfate (3:1),Glycine, Calcium Salt,Glycine, Calcium Salt (2:1),Glycine, Cobalt Salt,Glycine, Copper Salt,Glycine, Monoammonium Salt,Glycine, Monosodium Salt,Glycine, Sodium Hydrogen Carbonate,Acid, Aminoacetic,Calcium Salt Glycine,Cobalt Salt Glycine,Copper Salt Glycine,Hydrochloride, Glycine,Monoammonium Salt Glycine,Monopotassium Salt Glycine,Monosodium Salt Glycine,Phosphate, Glycine,Salt Glycine, Monoammonium,Salt Glycine, Monopotassium,Salt Glycine, Monosodium
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000217	Acyltransferases	Enzymes from the transferase class that catalyze the transfer of acyl groups from donor to acceptor, forming either esters or amides. (From Enzyme Nomenclature 1992) EC 2.3.	Acyltransferase
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
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001483	Base Sequence	The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.	DNA Sequence,Nucleotide Sequence,RNA Sequence,DNA Sequences,Base Sequences,Nucleotide Sequences,RNA Sequences,Sequence, Base,Sequence, DNA,Sequence, Nucleotide,Sequence, RNA,Sequences, Base,Sequences, DNA,Sequences, Nucleotide,Sequences, RNA