Biomaterial Database

Phenoxazinone biosynthesis: accumulation of a precursor, 4-methyl-3-hydroxyanthranilic acid, by mutants of Streptomyces parvulus. 1979

T Troost, and E Katz

Mutants of Streptomyces parvulus that are blocked in the synthesis of the phenoxazinone-containing antibiotic, actinomycin, were isolated by the 'agar piece' method (after ultraviolet irradiation or treatment with 8-methoxypsoralen plus near-ultraviolet light). Radiolabelling experiments in conjunction with paper, thin-layer and column chromatography revealed that 4-methyl-3-hydroxyanthranilic acid (MHA) is a major metabolite accumulated by these mutants. Studies in vitro and in vivo provided evidence that MHA is a precursor of the phenoxazinone chromophore, actinocin. Normally MHA does not accumulate during growth or antibiotic synthesis by the parental strains. Protoplasts derived from the mutant strain AM5 synthesized MHA in significant amounts. A scheme is proposed for the biosynthesis of actinomycin D that accounts for the accumulation of MHA by the mutants.

UI	MeSH Term	Description	Entries
D009154	Mutation	Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.	Mutations
D010078	Oxazines	Six-membered heterocycles containing an oxygen and a nitrogen.
D011523	Protoplasts	The protoplasm and plasma membrane of plant, fungal, bacterial or archaeon cells without the CELL WALL.	Protoplast
D003609	Dactinomycin	A compound composed of a two CYCLIC PEPTIDES attached to a phenoxazine that is derived from STREPTOMYCES parvullus. It binds to DNA and inhibits RNA synthesis (transcription), with chain elongation more sensitive than initiation, termination, or release. As a result of impaired mRNA production, protein synthesis also declines after dactinomycin therapy. (From AMA Drug Evaluations Annual, 1993, p2015)	Actinomycin,Actinomycin D,Meractinomycin,Cosmegen,Cosmegen Lyovac,Lyovac-Cosmegen,Lyovac Cosmegen,Lyovac, Cosmegen,LyovacCosmegen
D013302	Streptomyces	A genus of bacteria that form a nonfragmented aerial mycelium. Many species have been identified with some being pathogenic. This genus is responsible for producing a majority of the ANTI-BACTERIAL AGENTS of practical value.
D014364	Tryptophan	An essential amino acid that is necessary for normal growth in infants and for NITROGEN balance in adults. It is a precursor of INDOLE ALKALOIDS in plants. It is a precursor of SEROTONIN (hence its use as an antidepressant and sleep aid). It can be a precursor to NIACIN, albeit inefficiently, in mammals.	Ardeydorm,Ardeytropin,L-Tryptophan,L-Tryptophan-ratiopharm,Levotryptophan,Lyphan,Naturruhe,Optimax,PMS-Tryptophan,Trofan,Tryptacin,Tryptan,Tryptophan Metabolism Alterations,ratio-Tryptophan,L Tryptophan,L Tryptophan ratiopharm,PMS Tryptophan,ratio Tryptophan
D015095	3-Hydroxyanthranilic Acid	An oxidation product of tryptophan metabolism. It may be a free radical scavenger and a carcinogen.	3 Hydroxyanthranilic Acid,Acid, 3-Hydroxyanthranilic
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