Cysteine has been shown to inhibit growth in Escherichia coli strains C6 and HfrH 72, but not M108A. Growth inhibition was overcome by inclusion of isoleucine, leucine, and valine in the medium. Isoleucine biosynthesis was apparently affected, since addition of this amino acid alone could alter the inhibitory effects of cysteine. Homocysteine, mercaptoethylamine, and mercaptoethanol inhibited g...

The YjgF/YER057c/UK114 family is a highly conserved class of proteins that is represented in the three domains of life. Thus far, a biochemical function demonstrated for these proteins in vivo or in vitro has yet to be defined. In several organisms, strains lacking a YjgF homolog have a defect in branched-chain amino acid biosynthesis. This study probes the connection between yjgF and isoleucin...

Reticulocytes from newborn infants with Rh isoimmune hemolytic disease actively incorporated radioactive amino acids in vitro into hemoglobins F and A. Approximately 50% of the reticulocytes appeared capable of synthesis of both of these hemoglobins within the same cell, as demonstrated by the selective elution technique of Betke and Kleihauer. An isoleucine analogue, L-O-methylthreonine, inhib...

Isoleucine, one of several amino acids isolated from a suite of welldated deep-sea cores, shows a progressive increase in the degree of racemization with the age of the sediment. Amino acids in sediments show an initial rate of racemization almost an order of magnitude faster than the rate observed for free amino acids at a comparable pH and temperature. The observed kinetics depend on a variet...

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...

of aspergillic acid from isoleucine in replacement cultures (3), there has been no work reported previously on the biogenesis of this antibiotic. In the present work, A. flavus was grown on a medium containing radioactive leucine or isoleucine, and these compounds were found to be incorporated into the aspergillic acid formed. Aspergillic acid was degraded to determine what part of the molecule...

In recent years, a number of new functions branched-chain amino acids (BCAA) - leucine, valine and isoleucine have been revealed in various states the body animals humans. BCAA are involved regulation metabolism not only proteins, but also lipids carbohydrates, maintain health mammary glands intestines, help early implantation development embryos. increase protein synthesis currently considered...

In a previous paper (Kiritani and Inuzuka 1970) , it was reported that Salmonella typhimurium mutants deficient in both the branched-chain-amino-acid aminotransferase EC 2.6.1.6 (transaminase B) and the a, j3-dihydroxyacid dehydratase EC 4.2.1.9 required leucine in addition to isoleucine and valine for normal growth, whereas the known mutants deficient in transaminase B require only isoleucine,...

The Malarial parasite resides in the host RBC during its erythrocytic cycle. Plasmodium meets its entire nutritional requirement from RBC. It scavenges the hemoglobin of RBCs to meet its amino acid requirement. The host hemoglobin is made of different chains and it is dependent on age. Hemoglobin F (HbF), which has two-alpha and two gamma chain persists in children upto six years, and hemoglobi...

It is now believed that the amino groups of isoleucine and valine are accepted by their respective carbon chains during biosynthesis via a transamination. Most of the evidence for this hypothesis has been derived from experiments on isoleucineless and valineless mutants of Escherichia coli and Neurospora crassu (l-4). It is not positively established whether this transamination step can be medi...