Biomaterial Database

Regulation of tryptophan pyrrolase activity in Xanthomonas pruni. 1970

C Wagner, and A T Brown

Tryptophan pyrrolase was studied in partially purified extracts of Xanthomonas pruni. The dialyzed enzyme required both heme and ascorbate for maximal activity. Other reducing agents were able to substitute for ascorbate. Protoporphyrin competed with heme for the enzyme, suggesting that the native enzyme is a hemoprotein. The enzyme exhibited sigmoid saturation kinetics. Reduced nicotinamide adenine dinucleotide (NADH), reduced nicotinamide adenine dinucleotide phosphate (NADPH), nicotinic acid mononucleotide, and anthranilic acid enhanced the sigmoid kinetics and presumably bound to allosteric sites on the enzyme. The sigmoid kinetics were diminished in the presence of alpha-methyltryptophan. NAD, NADP, nicotinic acid, nicotinamide, nicotinamide mononucleotide, and several other related compounds were without effect on the activity of the enzyme. These data indicate that the activity of the enzyme is under feedback regulation by the ultimate end products of the pathway leading to NAD biosynthesis, as well as by certain intermediates of this pathway.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D007737	Kynurenine	A metabolite of the essential amino acid tryptophan metabolized via the tryptophan-kynurenine pathway.
D009536	Niacinamide	An important compound functioning as a component of the coenzyme NAD. Its primary significance is in the prevention and/or cure of blacktongue and PELLAGRA. Most animals cannot manufacture this compound in amounts sufficient to prevent nutritional deficiency and it therefore must be supplemented through dietary intake.	Nicotinamide,Vitamin B 3,Vitamin PP,3-Pyridinecarboxamide,Enduramide,Nicobion,Nicotinsäureamid Jenapharm,Papulex,Vitamin B3,3 Pyridinecarboxamide,B 3, Vitamin,B3, Vitamin,Jenapharm, Nicotinsäureamid
D009539	Nicotinic Acids	2-, 3-, or 4-Pyridinecarboxylic acids. Pyridine derivatives substituted with a carboxy group at the 2-, 3-, or 4-position. The 3-carboxy derivative (NIACIN) is active as a vitamin.	Acids, Nicotinic
D011166	Porphyrins	A group of compounds containing the porphin structure, four pyrrole rings connected by methine bridges in a cyclic configuration to which a variety of side chains are attached. The nature of the side chain is indicated by a prefix, as uroporphyrin, hematoporphyrin, etc. The porphyrins, in combination with iron, form the heme component in biologically significant compounds such as hemoglobin and myoglobin.	Porphyrin
D006418	Heme	The color-furnishing portion of hemoglobin. It is found free in tissues and as the prosthetic group in many hemeproteins.	Ferroprotoporphyrin,Protoheme,Haem,Heme b,Protoheme IX
D001205	Ascorbic Acid	A six carbon compound related to glucose. It is found naturally in citrus fruits and many vegetables. Ascorbic acid is an essential nutrient in human diets, and necessary to maintain connective tissue and bone. Its biologically active form, vitamin C, functions as a reducing agent and coenzyme in several metabolic pathways. Vitamin C is considered an antioxidant.	Vitamin C,Ascorbic Acid, Monosodium Salt,Ferrous Ascorbate,Hybrin,L-Ascorbic Acid,Magnesium Ascorbate,Magnesium Ascorbicum,Magnesium di-L-Ascorbate,Magnorbin,Sodium Ascorbate,Acid, Ascorbic,Acid, L-Ascorbic,Ascorbate, Ferrous,Ascorbate, Magnesium,Ascorbate, Sodium,L Ascorbic Acid,Magnesium di L Ascorbate,di-L-Ascorbate, Magnesium
D014366	Tryptophan Oxygenase	A dioxygenase with specificity for the oxidation of the indoleamine ring of TRYPTOPHAN. It is a LIVER-specific enzyme that is the first and rate limiting enzyme in the kynurenine pathway of TRYPTOPHAN catabolism.	Tryptophan Pyrrolase,TDO Dioxygenase,Tryptophan 2,3-Dioxygenase,2,3-Dioxygenase, Tryptophan,Dioxygenase, TDO,Oxygenase, Tryptophan,Pyrrolase, Tryptophan,Tryptophan 2,3 Dioxygenase
D014974	Xanthomonas	A genus in the family XANTHOMONADACEAE whose cells produce a yellow pigment (Gr. xanthos - yellow). It is pathogenic to plants.	Xanthomonas albilineans
D062367	ortho-Aminobenzoates	Benzoic acids, salts, or esters that contain an amino group attached to carbon number 2 or 6 of the benzene ring structure.	2-Aminobenzoates,6-Aminobenzoates,Anthranilates,Anthranilic Acids,o-Aminobenzoates,o-Aminobenzoic Acids,ortho-Aminobenzoic Acids,6 Aminobenzoates,Acids, Anthranilic,Acids, o-Aminobenzoic,Acids, ortho-Aminobenzoic,o Aminobenzoates,o Aminobenzoic Acids,ortho Aminobenzoates,ortho Aminobenzoic Acids