Biomaterial Database

The amidating enzyme in pituitary will accept a peptide with C-terminal D-alanine as substrate. 1983

A E Landymore-Lim, and A F Bradbury, and D G Smyth

A series of tripeptides which terminated in d-alanine, d-serine, d-leucine or l-alanine was synthesized and the peptides tested for their ability to act as substrates for an amidating enzyme present in porcine pituitary. The peptides were allowed to compete with a radiolabelled substrate 125I d-Tyr Phe Gly in the presence of a rate limiting concentration of amidating enzyme and the degree of conversion to 125I d-Tyr Phe amide was determined by ion exchange chromatography. An accelerated procedure was developed for investigating the rates of reaction. The results showed that d-Tyr Phe d-Ala has a significant affinity for the amidating enzyme; no affinity could be demonstrated with d-Tyr Phe 1-Ala, d-Tyr Phe d-Ser or d-Tyr Phe d-Leu. Direct evidence that d-Tyr Phe d-Ala can undergo amidation was obtained by incubating the 125I labelled tripeptide with the pituitary enzyme. Amidation took place readily with d-Tyr Phe d-Ala but not with the other tripeptides; thus, while the enzyme is unable to catalyse the conversion of a peptide terminating in 1-alanine, it can accept a peptide terminating in d-alanine. The results indicate that the amidating enzyme has a highly compact substrate binding site.

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
D009842	Oligopeptides	Peptides composed of between two and twelve amino acids.	Oligopeptide
D010902	Pituitary Gland	A small, unpaired gland situated in the SELLA TURCICA. It is connected to the HYPOTHALAMUS by a short stalk which is called the INFUNDIBULUM.	Hypophysis,Hypothalamus, Infundibular,Infundibular Stalk,Infundibular Stem,Infundibulum (Hypophysis),Infundibulum, Hypophyseal,Pituitary Stalk,Hypophyseal Infundibulum,Hypophyseal Stalk,Hypophysis Cerebri,Infundibulum,Cerebri, Hypophysis,Cerebrus, Hypophysis,Gland, Pituitary,Glands, Pituitary,Hypophyseal Stalks,Hypophyses,Hypophysis Cerebrus,Infundibular Hypothalamus,Infundibular Stalks,Infundibulums,Pituitary Glands,Pituitary Stalks,Stalk, Hypophyseal,Stalk, Infundibular,Stalks, Hypophyseal,Stalks, Infundibular
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
D000409	Alanine	A non-essential amino acid that occurs in high levels in its free state in plasma. It is produced from pyruvate by transamination. It is involved in sugar and acid metabolism, increases IMMUNITY, and provides energy for muscle tissue, BRAIN, and the CENTRAL NERVOUS SYSTEM.	Abufène,Alanine, L-Isomer,L-Alanine,Alanine, L Isomer,L Alanine,L-Isomer Alanine
D000577	Amides	Organic compounds containing the -CO-NH2 radical. Amides are derived from acids by replacement of -OH by -NH2 or from ammonia by the replacement of H by an acyl group. (From Grant & Hackh's Chemical Dictionary, 5th ed)	Amide
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
D013379	Substrate Specificity	A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.	Specificities, Substrate,Specificity, Substrate,Substrate Specificities
D013552	Swine	Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).	Phacochoerus,Pigs,Suidae,Warthogs,Wart Hogs,Hog, Wart,Hogs, Wart,Wart Hog