Aspartokinase or Aspartate kinase is an enzyme that catalysis catalyzes the phosphorylation of the amino acid aspartate . This reaction is the first step in the biosynthesis of three essential amino acid s methionine , lysine , and threonine , known as the aspartate family . The gene for aspartokinase is present only in microorganism s and plant s it is not present in animal s, which must obtain aspartate family amino acids in their diet nutrition diet . In E. coli , aspartokinase is present as three independently regulated isozyme s, each of which is specific to one of the three downstream biochemical pathways. This allows the independent regulation of the rates of methionine, lysine, and threonine production. The forms that produce threonine and lysine are subject to enzyme inhibition feedback inhibition , and all three can be repressed at the level of gene expression by high concentrations of their end products. ref cite journal author Voet D, Voet JG. year 2004 title The Personal Genome Project volume 1 pmid 16729065 doi 10.1038 msb4100040 journal Molecular Systems Biology pages E1 pmc 1681452 issue 1 ref Absence from animals makes these enzymes key targets for new herbicides and biocides and for improvements in nutritional value of crops. ref cite journal author Viola RE. journal Acc Chem Res. year 2001 vol 34 title The central enzymes of the aspartate family of amino acid biosynthesis pmid 11352712 pages 339 49 doi 10.1021 ar000057q volume 34 issue 5 ref This protein may use the morpheein model of allosteric regulation . ref name pmid22182754 cite journal author T. Selwood and E. K. Jaffe. title Dynamic dissociating homo oligomers and the control of protein function. journal Arch. Biochem. Biophys. volume 519 issue 2 pages 131 43 year 2011 pmid 22182754 url http www.ncbi.nlm.nih.gov entrez query.fcgi?cmd Retrieve&db PubMed&dopt Citation&list uids 22182754 doi 10.1016 ... links EC number 2.7.2.4 MeshName Aspartokinase Kinases Amino acid metabolism enzymes Category EC 2.7.2 ... more details
Infobox protein family Symbol AA kinase Name AA kinase image PDB 2bty EBI.jpg width caption acetylglutamate kinase from thermotoga maritima complexed with its inhibitor arginine Pfam PF00696 Pfam clan InterPro IPR001048 SMART PROSITE PDOC00289 MEROPS SCOP 1e19 TCDB OPM family OPM protein CAZy CDD In molecular biology, the amino acid kinase domain is a protein domain. It is found in protein kinases with various specificities, including the aspartate kinase aspartate , glutamate and uridylate kinase families. In prokaryotes and plants the synthesis of the essential amino acid s lysine and threonine is predominantly regulated by feed back inhibition of aspartate kinase AK and dihydrodipicolinate synthase DHPS . In Escherichia coli , thrA, metLM, and lysC encode aspartokinase isozymes that show feedback inhibition by threonine, methionine, and lysine, respectively. ref name pmid10220897 cite journal author Kikuchi Y, Kojima H, Tanaka T title Mutational analysis of the feedback sites of lysine sensitive aspartokinase of Escherichia coli journal FEMS Microbiol. Lett. volume 173 issue 1 pages 211 5 year 1999 month April pmid 10220897 doi url ref The lysine sensitive isoenzyme of aspartic acid aspartate kinase from spinach leaf leaves has a subunit composition of 4 large and 4 small protein subunit subunits . ref name pmid9584993 cite journal author Kochhar S, Kochhar VK, Sane PV title Subunit structure of lysine sensitive aspartate kinase from spinach leaves journal Biochem. Mol. Biol. Int. volume 44 issue 4 pages 795 806 year 1998 month April pmid 9584993 doi url ref In plant s although the control of carbon fixation and nitrogen assimilation has been studied in detail, relatively little is known about the regulation of carbon and nitrogen flow into amino acids . The metabolism metabolic regulation of gene expression expression of an Arabidopsis thaliana Arabidopsis thaliana aspartate kinase homoserine dehydrogenase AK HSD gene, which encodes two linked key enzyme s in th ... more details
bacteria and yeast , or a bifunctional form consisting of an N terminal aspartokinase protein domain ... WL, Munk P, Maul SB, Cunningham GN, Cox DJ, Shive W year 1972 title Threonine sensitive aspartokinase ... homoserine dehydrogenase and aspartokinase activities of Escherichia coli K12. The two catalytic ... more details
enzyme Name UMP kinase EC number 2.7.4.22 CAS number 9036 23 1 IUBMB EC number 2 7 4 22 GO code 0033862 image width caption In enzymology , an UMP kinase EC number 2.7.4.22 is an enzyme that catalysis catalyzes the chemical reaction ATP UMP math rightleftharpoons math ADP UDP Thus, the two substrate biochemistry substrates of this enzyme are adenosine triphosphate ATP and uridine monophosphate UMP , whereas its two product chemistry products are adenosine diphosphate ADP and uridine diphosphate UDP . This enzyme belongs to the family of transferase s, specifically those transferring phosphorus containing groups phosphotransferase s with a phosphate group as acceptor. The systematic name of this enzyme class is ATP UMP phosphotransferase . Other names in common use include uridylate kinase , UMPK , uridine monophosphate kinase , PyrH , UMP kinase , and SmbA . This enzyme participates in pyrimidine metabolism . Structural studies As of March 2010, 19 tertiary structure structures have been solved for this class of enzymes, and are deposited in the Protein Data Bank PDB . All have a 3 layer aba sandwich architecture CATH code 3.40.1160.10 . These include accession codes PDB link 2J4J , PDB link 2J4K , PDB link 2J4L , and PDB link 2VA1 . Search for all UMP Kinases in the PDB using the http www.ebi.ac.uk pdbe srv PDBeXplore enzyme enzyme Browser at http www.pdbe.org PDBe . input the EC number References reflist 1 cite journal author Gilles AM, Barzu O date 1995 title Escherichia coli UMP kinase, a member of the aspartokinase family, is a hexamer regulated by guanine nucleotides and UTP journal Biochemistry. volume 34 pages 5066 5074 pmid 7711027 doi 10.1021 bi00015a018 issue 15 cite journal author Marco Marin C, Gil Ortiz F, Rubio V date 2005 title The crystal structure of Pyrococcus furiosus UMP kinase provides insight into catalysis and regulation in microbial pyrimidine nucleotide biosynthesis journal J. Mol. Biol. volume 352 pages 438 454 pmid 16095620 doi 10.1016 j. ... more details
Infobox protein family Symbol ACT Name ACT image PDB 2j0w EBI.jpg width caption crystal structure of e. coli aspartokinase iii in complex with aspartate and adp r state Pfam PF01842 Pfam clan CL0070 InterPro IPR002912 SMART PROSITE MEROPS SCOP 1psd TCDB CDD cd02116 OPM family OPM protein CAZy In molecular biology, the ACT domain is a protein domain that is found in a variety of contexts and is proposed to be a conserved sequence conserved regulatory Binding molecular binding protein folding fold . ACT protein domain domains are linked to a wide range of metabolism metabolic enzyme s that are regulated by amino acid concentration . The archetypical ACT domain is the C terminal regulatory domain of 3 phosphoglycerate dehydrogenase 3PGDH , which tertiary structure fold s with a ferredoxin like topology. A pair of ACT protein domains domains form an eight stranded Antiparallel biochemistry antiparallel sheet with two molecule s of allosteric inhibitor serine bound in the interface. Biochemistry Biochemical exploration of a few other protein s containing ACT domains supports the suggestions that these domains contain the archetypical ACT secondary structure structure . ref name pmid11751050 cite journal author Chipman DM, Shaanan B title The ACT domain family journal Curr. Opin. Struct. Biol. volume 11 issue 6 pages 694 700 year 2001 month December pmid 11751050 doi 10.1016 S0959 440X 01 00272 X url ref References reflist InterPro content IPR002912 Category Protein domains ... more details
. Without this pathway, protein synthesis would not be possible. Aspartate The enzyme aspartokinase ... by aspartokinase and aspartate semialdehyde dehydrogenase and play a key role in the biosynthesis of lysine, threonine and methionine. There are two bifuctional aspartokinase homoserine dehydrogenases, ThrA and MetL, in addition to a monofunctional aspartokinase, LysC. Transcription of aspartokinase ... more details
Diastereomers L aspartate is first converted to L aspartyl 4 phosphate by aspartokinase ... Publishing New York, 2000. ISBN 1 57259 153 6. ref Aspartokinase Aspartate semialdehyde dehydrogenase ... more details
For other categories, see List of MeSH codes . This is the fourth part of the list of the D codes for MeSH . It is a product of the United States National Library of Medicine . Source for content is http www.nlm.nih.gov mesh filelist.html here . File 2006 MeSH Trees . MeshNumber D08 Enzymes and Coenzymes enzymes and coenzymes MeshNumber D08.211 Coenzymes coenzymes MeshNumber D08.211.090 Biopterin biopterin MeshNumber D08.211.090.500 Neopterin neopterin MeshNumber D08.211.096 Biotin biotin MeshNumber D08.211.175 Cobamides cobamides MeshNumber D08.211.211 Coenzyme A coenzyme a MeshNumber D08.211.211.300 Acyl Coenzyme A acyl coenzyme a MeshNumber D08.211.211.300.075 Acetyl Coenzyme A acetyl coenzyme a MeshNumber D08.211.211.300.500 Malonyl Coenzyme A malonyl coenzyme a MeshNumber D08.211.211.300.700 Palmitoyl Coenzyme A palmitoyl coenzyme a MeshNumber D08.211.474 Flavins flavins MeshNumber D08.211.474.650 Riboflavin riboflavin MeshNumber D08.211.474.650.249 Flavin Adenine Dinucleotide flavin adenine dinucleotide MeshNumber D08.211.474.650.500 Flavin Mononucleotide flavin mononucleotide MeshNumber D08.211.589 NAD nad MeshNumber D08.211.625 NADP nadp MeshNumber D08.211.682 PQQ Cofactor pqq cofactor MeshNumber D08.211.740 Pyridoxal Phosphate pyridoxal phosphate MeshNumber D08.211.790 Sphingolipid Activator Proteins sphingolipid activator proteins MeshNumber D08.211.790.249 G M2 Activator Protein g m2 activator protein MeshNumber D08.211.790.500 Saposins saposins MeshNumber D08.211.840 Tetrahydrofolates tetrahydrofolates MeshNumber D08.211.840.300 Formyltetrahydrofolates formyltetrahydrofolates MeshNumber D08.211.840.300.500 Leucovorin leucovorin MeshNumber D08.211.878 Thiamine Pyrophosphate thiamine pyrophosphate MeshNumber D08.211.906 Thioctic Acid thioctic acid MeshNumber D08.211.935 Ubiquinone ubiquinone MeshNumber D08.244 Cytochromes cytochromes MeshNumber D08.244.175 Cytochrome a Group cytochrome a group MeshNumber D08.244.175.249 Cytochromes a cytochromes a MeshNumb ... more details
PubMed&dopt Citation&list uids 17451745 doi 10.1016 j.jmb.2007.03.061 pmc 1991333 ref Aspartokinase ... aspartokinase III. Mechanisms of the allosteric transition and inhibition by lysine. journal J. Biol ..., L. P. Vickers, R. B. Clark and M. M. Jones title Aspartokinase I homoserine dehydrogenase I of Escherichia ... more details
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