Biomaterial Database

Pancreatic carboxylester lipase from Atlantic salmon (Salmo salar). cDNA sequence and computer-assisted modelling of tertiary structure. 1994

D R Gjellesvik, and J B Lorens, and R Male

Laboratory for Marine Molecular Biology, University of Bergen, Norway.

We report the isolation and characterization of a 1795-bp cDNA fragment encoding Atlantic salmon pancreatic carboxylester lipase from salmon pancreas mRNA. The nearly full-length cDNA contained a 540-amino-acid open-reading frame, encompassing the mature protein (by similarity to mammalian carboxylester lipase enzymes). The salmon carboxylester lipase primary structure shared 58% identity with mammalian carboxylester lipases, lacking the proline-rich C-terminal repeats found in human and rat carboxylester lipases. Congruent with other esterase B type enzymes, the salmon carboxylester lipase contained a canonical serine-esterase catalytic triad motif consisting of serine, histidine and aspartic acid. Computer-assisted modelling of the tertiary structure for salmon carboxylester lipase was conducted using acetylcholine esterase (Torpedo californica) as a template structure. The model, in conjunction with sequence comparisons and available enzymological data, has been used to locate putative bile-salt-binding and lipid-binding sites. The carboxylester lipase enzymes contain a unique, highly conserved insert region that may be associated with bile-salt binding. In the model structure, this region is located close to the active site, and contains a tyrosine residue with an adjacent carboxylester-lipase-conserved arginine. These traits have previously been predicted for the non-specific (regarding bile-salt hydroxylation) bile-salt-binding site in carboxylester lipase enzymes. At this site, a dihydroxy or trihydroxy bile-salt molecule may bind the tyrosine via hydrophobic interactions, the anionic bile-salt head group may bind the arginine, while hydrogen bonding between the bile-salt 12 alpha hydroxy group and an adjacent aspargine residue is possible. The model does not contain an active site 'lid' structure as found in other lipases. The carboxylester lipase structural homolog to the 'flap' of the lipases from Geotrichum candidum and Candida rugosa contains a carboxylester-lipase-conserved deletion that renders this region unable to cover the active site. Instead, the shortening of this loop leads to solvent exposure of the carboxylester lipase insert region, an additional indication of the functional importance of this region.

UI	MeSH Term	Description	Entries
D008958	Models, Molecular	Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.	Molecular Models,Model, Molecular,Molecular Model
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
D010179	Pancreas	A nodular organ in the ABDOMEN that contains a mixture of ENDOCRINE GLANDS and EXOCRINE GLANDS. The small endocrine portion consists of the ISLETS OF LANGERHANS secreting a number of hormones into the blood stream. The large exocrine portion (EXOCRINE PANCREAS) is a compound acinar gland that secretes several digestive enzymes into the pancreatic ductal system that empties into the DUODENUM.
D002265	Carboxylic Ester Hydrolases	Enzymes which catalyze the hydrolysis of carboxylic acid esters with the formation of an alcohol and a carboxylic acid anion.	Carboxylesterases,Ester Hydrolases, Carboxylic,Hydrolases, Carboxylic Ester
D003198	Computer Simulation	Computer-based representation of physical systems and phenomena such as chemical processes.	Computational Modeling,Computational Modelling,Computer Models,In silico Modeling,In silico Models,In silico Simulation,Models, Computer,Computerized Models,Computer Model,Computer Simulations,Computerized Model,In silico Model,Model, Computer,Model, Computerized,Model, In silico,Modeling, Computational,Modeling, In silico,Modelling, Computational,Simulation, Computer,Simulation, In silico,Simulations, Computer
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
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
D001647	Bile Acids and Salts	Steroid acids and salts. The primary bile acids are derived from cholesterol in the liver and usually conjugated with glycine or taurine. The secondary bile acids are further modified by bacteria in the intestine. They play an important role in the digestion and absorption of fat. They have also been used pharmacologically, especially in the treatment of gallstones.	Bile Acid,Bile Salt,Bile Salts,Bile Acids,Acid, Bile,Acids, Bile,Salt, Bile,Salts, Bile