In actinomycetes the catabolism products of branched chain amino acids provide biosynthetic precursors for the formation of several lipid-containing antibiotics. We have determined in Nonomuraea sp. ATCC 39727 the effect of valine on production of glycopeptide antibiotic A40926, which is a complex of factors structurally differing in fatty acid moieties. Addition of valine to minimal medium inc...

Urine specimens dried on filter paper squares were obtained from 700 mentally retarded children. A microbiological assay was used to screen the specimens for the presence of valine, leucine, and isoleucine. Three specimens gave positive tests for all three amino acids. A generalized aminoaciduria was observed in two specimens, and in the third, elevation of valine and leucine/isoleucine was con...

l-[3,3'-(3)H]cystine was incorporated into penicillin with retention of one tritium. This result can be explained by beta-lactam formation through ring closure between C3 of cysteine and NH of valine. No radioactivity of dl-[2,3-(3)H]valine was incorporated into penicillin. The loss of isotope at C2 occurs during the inversion of configuration. The loss of label at C3 is discussed in terms of p...

Of the L and D configurations of four amino acids (phenylalanine, valine, tryptophan, tyrosine) tested for influence on the growth rate of Tetrahymena, only L-tyrosine was able to induce imprinting in Tetrahymena pyriformis Zeuthen. D-valine stimulated the division of T.pyriformis NT-1, but failed to induce imprinting. The experiments have substantiated the selectivity of the amino acid recepto...

L-Valine solutions in water and phosphate buffer were treated with nonthermal plasma generated by using a dielectric barrier discharge (DBD) device and the products generated after plasma treatments were characterized by (1)H NMR and GC-MS. Our results demonstrate that L-valine is decomposed to acetone, formic acid, acetic acid, threo-methylaspartic acid, erythro-methlyaspartic acid, and pyruvi...