Disease relevance of AI3-03136

• Glutamate 636 of the Escherichia coli pyruvate dehydrogenase-E1 participates in active center communication and behaves as an engineered acetolactate synthase with unusual stereoselectivity [1].
• The crystal structures of Klebsiella pneumoniae acetolactate synthase with enzyme-bound cofactor and with an unusual intermediate [2].
• Several characteristics identify the protein encoded by the alsS gene [sll1981 in Cyanobase (http://www.kazusa.or.jp/cyano/cyano. html)] of Synechocystis PCC6803 as an acetolactate synthase [3].
• A facile purification has been devised for recombinantly produced Salmonella typhimurium acetolactate synthase isozyme II [4].
• Degradative acetolactate synthase of Bacillus subtilis: purification and properties [5].

High impact information on AI3-03136

• In confirmation of its identity, cells lacking the gene for this carrier had reduced levels of ThPP in their mitochondria, and decreased activity of acetolactate synthase, a ThPP-requiring enzyme found in the organellar matrix [6].
• These enzymes condense two pyruvates to form acetolactate, implicated in pH homeostasis via the acetoin-2, 3-butanediol pathway or in valine biosynthesis [3].
• Nucleotide sequence of the yeast ILV2 gene which encodes acetolactate synthase [7].
• Molecular analysis of the acetolactate synthase gene of Chlamydomonas reinhardtii and development of a genetically engineered gene as a dominant selectable marker for genetic transformation [8].
• Regulation of tobacco acetolactate synthase gene expression [9].

Chemical compound and disease context of AI3-03136

• Acetohydroxy acid synthase (AHAS, EC 4.1.3.18) isozyme III from Escherichia coli has been studied in steady-state kinetic experiments in which the rates of formation of acetolactate (AL) and acetohydroxybutyrate (AHB) have been determined simultaneously [10].
• Examination of the ilvF locus at 54 min on the Escherichia coli K-12 chromosome revealed that it is a cryptic gene for expression of a valine-resistant acetohydroxy acid synthase (acetolactate synthase; EC 4.1.3.18) distinct from previously reported isozymes [11].
• Toxic accumulation of alpha-ketobutyrate caused by inhibition of the branched-chain amino acid biosynthetic enzyme acetolactate synthase in Salmonella typhimurium [12].
• Metabolic interlock between the acetolactate synthase isoenzymes and lysine biosynthesis in Escherichia coli K-12 [13].
• The introduction of a Bacillus subtilis acetolactate synthase gene returned formate, ethanol, and lactate levels to those of the wild type (ackA(+)pta(+)nuo(+)) strain [14].

Biological context of AI3-03136

• AHAS catalyzes the condensation of the 2-carbon moiety, derived from the decarboxylation of pyruvate, with a second 2-ketoacid, to form acetolactate or acetohydroxybutyrate [15].
• These results provide the first direct evidence that AHAS I catalyzes both acetohydroxybutyrate and acetolactate synthesis from the same active site [16].
• In vivo expression of the acetolactate synthase-encoding gene in E. coli revealed a single 60-kDa protein which is consistent with the molecular weight calculated from the deduced amino acid sequence of the gene product [17].
• The recently discovered phosphorylation of acetolactate decarboxylase may provide an additional level of control of metabolism [18].
• Protein trans-splicing to produce herbicide-resistant acetolactate synthase [19].

Anatomical context of AI3-03136

• Although a major part of the acetolactate synthase synthesized by E. coli cells harbouring this vector was packaged into protein inclusion bodies, we used these recombinant E. coli cells to produce large quantities of the yeast enzyme [20].

Associations of AI3-03136 with other chemical compounds

• Additionally, we discuss the role of acetohydroxybutyrate and acetolactate in ilvY transcriptional regulation [21].
• The pattern of incorporation of radioactivity from [U-14C]valine, [U-14C]alanine and NaH14CO3 into the side-chain of ubiquinone of R. capsulata was in agreement with the operation of the 'acetolactate pathway' [22].
• Sulfometuron methyl-sensitive and -resistant acetolactate synthases of the archaebacteria Methanococcus spp [23].
• ilvB-encoded acetolactate synthase is resistant to the herbicide sulfometuron methyl [24].
• The specificity of the BCAA biosynthesis pathway in S. thermophilus lies in the independent transcription of the ilvC gene encoding a keto acid reductoisomerase acting on acetolactate at the junction of the BCAA and acetoin biosynthesis pathways [25].

Gene context of AI3-03136

• Besides the expected ilvG gene product (59.3 kDa), purified acetolactate synthase contained a smaller subunit (9.7 kDa; designated here as the ilvM gene product) [4].
• We isolated, in E. coli K12, new alleles of the ilvB locus, the structural gene for acetolactate synthase isoenzyme I, and showed them to map at or near the ilvB619 site [26].
• Saccharomyces cerevisiae laboratory strains with an inactive ilv2 gene can not form acetolactate, while ilv5 strains, blocked in the subsequent step, leak acetolactate in high amounts [27].
• Constricted flux through the branched-chain amino acid biosynthetic enzyme acetolactate synthase triggers elevated expression of genes regulated by rpoS and internal acidification [28].
• In the case of KARI inhibition, it is proposed that fermentation induction is due to an inhibition of ALS activity resulted from an increase in acetolactate concentration [29].

Analytical, diagnostic and therapeutic context of AI3-03136

• Purification, crystallization and preliminary X-ray crystallographic studies on acetolactate decarboxylase [30].
• The specificity of these antibodies against sugar beet acetolactate synthetase was verified using immunoblotting, ELISA, and immunoprecipitation [31].

References