Biomaterial Database

Control of isoleucine-valine biosynthesis in a valine-resistant mutant of Escherichia coli K-12 that simultaneously acquired azaleucine-resistance. 1985

A L Williams, and L S Williams

A mutant of Escherichia coli K-12 isolated as being growth resistant to L-valine (Valr) was shown also to exhibit growth resistance to 4-azaleucine (Azlr). Transductional analysis indicated that Azlr is cotransduced with Valr at a frequency of 100% and both are linked to leu, ara, and carA. This mutation conferring valine and azaleucine growth resistance resulted in increased levels of isoleucine and valine biosynthetic enzymes as well as those of valyl- and isoleucyl-tRNA synthetases during growth in minimal and enriched media. Acquisition of Vals/Azls results in the restoration of normal regulation of both classes of ilv enzymes and normal patterns of the tRNA Ile species. The overall regulatory patterns observed for individual isoleucine and valine gene products suggest differential participation of isoleucine and valine and/or isoleucyl- and valyl-tRNA's in control of expression of the respective structural genes.

UI	MeSH Term	Description	Entries
D007532	Isoleucine	An essential branched-chain aliphatic amino acid found in many proteins. It is an isomer of LEUCINE. It is important in hemoglobin synthesis and regulation of blood sugar and energy levels.	Alloisoleucine,Isoleucine, L-Isomer,L-Isoleucine,Isoleucine, L Isomer,L-Isomer Isoleucine
D007930	Leucine	An essential branched-chain amino acid important for hemoglobin formation.	L-Leucine,Leucine, L-Isomer,L-Isomer Leucine,Leucine, L Isomer
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
D004926	Escherichia coli	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.	Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli
D006836	Hydro-Lyases	Enzymes that catalyze the breakage of a carbon-oxygen bond leading to unsaturated products via the removal of water. EC 4.2.1.	Dehydratase,Dehydratases,Hydrase,Hydrases,Hydro Lyase,Hydro-Lyase,Hydro Lyases,Lyase, Hydro,Lyases, Hydro
D000095	Acetolactate Synthase	A flavoprotein enzyme that catalyzes the formation of acetolactate from 2 moles of PYRUVATE in the biosynthesis of VALINE and the formation of acetohydroxybutyrate from pyruvate and alpha-ketobutyrate in the biosynthesis of ISOLEUCINE. This enzyme was formerly listed as EC 4.1.3.18.	Acetohydroxy Acid Synthase,Acetohydroxy Acid Synthetase,Acetolactate Synthetase,Acetohydroxyacid Synthetase I,Acetoxyhydroxyacid Synthase III,Acid Synthase, Acetohydroxy,Acid Synthetase, Acetohydroxy,Synthase III, Acetoxyhydroxyacid,Synthase, Acetohydroxy Acid,Synthase, Acetolactate,Synthetase I, Acetohydroxyacid,Synthetase, Acetohydroxy Acid,Synthetase, Acetolactate
D000604	Amino Acyl-tRNA Synthetases	A subclass of enzymes that aminoacylate AMINO ACID-SPECIFIC TRANSFER RNA with their corresponding AMINO ACIDS.	Amino Acyl T RNA Synthetases,Amino Acyl-tRNA Ligases,Aminoacyl Transfer RNA Synthetase,Aminoacyl-tRNA Synthetase,Transfer RNA Synthetase,tRNA Synthetase,Acyl-tRNA Ligases, Amino,Acyl-tRNA Synthetases, Amino,Amino Acyl tRNA Ligases,Amino Acyl tRNA Synthetases,Aminoacyl tRNA Synthetase,Ligases, Amino Acyl-tRNA,RNA Synthetase, Transfer,Synthetase, Aminoacyl-tRNA,Synthetase, Transfer RNA,Synthetase, tRNA,Synthetases, Amino Acyl-tRNA
D013913	Threonine Dehydratase	A pyridoxal-phosphate protein that catalyzes the deamination of THREONINE to 2-ketobutyrate and AMMONIA. The role of this enzyme can be biosynthetic or biodegradative. In the former role it supplies 2-ketobutyrate required for ISOLEUCINE biosynthesis, while in the latter it is only involved in the breakdown of threonine to supply energy. This enzyme was formerly listed as EC 4.2.1.16.	Threonine Deaminase,Threonine Dehydrase,Threonine Ammonia-Lyase,Ammonia-Lyase, Threonine,Deaminase, Threonine,Dehydrase, Threonine,Dehydratase, Threonine,Threonine Ammonia Lyase
D014161	Transduction, Genetic	The transfer of bacterial DNA by phages from an infected bacterium to another bacterium. This also refers to the transfer of genes into eukaryotic cells by viruses. This naturally occurring process is routinely employed as a GENE TRANSFER TECHNIQUE.	Genetic Transduction,Genetic Transductions,Transductions, Genetic
D014633	Valine	A branched-chain essential amino acid that has stimulant activity. It promotes muscle growth and tissue repair. It is a precursor in the penicillin biosynthetic pathway.	L-Valine,L Valine