>TIGR01798 cit_synth_I citrate synthase I; InterPro: IPR010953 Citrate synthase 2.3.3.1 from EC is a member of a small family of enzymes that can directly form a carbon-carbon bond without the presence of metal ion cofactors. It catalyses the first reaction in the Krebs' cycle, namely the conversion of oxaloacetate and acetyl-coenzyme A into citrate and coenzyme A. This reaction is important for energy generation and for carbon assimilation. The reaction proceeds via a non-covalently bound citryl-coenzyme A intermediate in a 2-step process (aldol-Claisen condensation followed by the hydrolysis of citryl-CoA). Citrate synthase enzymes are found in two distinct structural types: type I enzymes (found in eukaryotes, Gram-positive bacteria and archaea) form homodimers and have shorter sequences than type II enzymes, which are found in Gram-negative bacteria and are hexameric in structure. In both types, the monomer is composed of two domains: a large alpha-helical domain consisting of two structural repeats, where the second repeat is interrupted by a small alpha-helical domain. The cleft between these domains forms the active site, where both citrate and acetyl-coenzyme A bind. The enzyme undergoes a conformational change upon binding of the oxaloacetate ligand, whereby the active site cleft closes over in order to form the acetyl-CoA binding site . The energy required for domain closure comes from the interaction of the enzyme with the substrate. Type II enzymes possess an extra N-terminal beta-sheet domain, and some type II enzymes are allosterically inhibited by NADH . This entry represents type II homohexameric citrate synthase enzymes, which are predominantly found in Gram-negative bacteria . These enzymes are allosterically inhibited by NADH in Escherichia coli, Acinetobacter calcoaceticus subsp. anitratus, Azotobacter vinelandii, Pseudomonas aeruginosa, etc . However, other type II enzymes in this entry do not display allosteric regulation. ; GO: 0004108 citrate (Si)-synthase activity, 0044262 cellular carbohydrate metabolic process, 0005737 cytoplasm.

Probab=100.00 E-value=0 Score=897.77 Aligned_cols=411 Identities=65% Similarity=1.132 Sum_probs=404.8 Q ss_pred CEEEEEEEECCCCCCCCEEECCCC-CCCEEEECCCCCCEEEEEEEEEEEECCCCEEEECCEEHHHHHHHCCHHHHHHHHH Q ss_conf 989997523077787510100115-5861898888786238787565433447778989931999975089899999998 Q gi|254780355|r 12 HEEIDLPIKEGSLGSSVLDISFLH-KNGIFTYDPAFSSTASCKSKITFIDGNNGILLYRGYPIEQLSEKSDFLEVCYLLL 90 (429) Q Consensus 12 ~~~~~lpi~~~~~~~~~~d~~~l~-~~G~~~~dpG~~~ta~ceS~IT~IDG~~G~L~YRGY~IedLa~~~sFeEVayLLl 90 (429) T Consensus 1 ~~~~~l~~~~~~~G~~v~d~~~l~~~~G~f~~d~Gf~~ta~C~s~it~idG~~G~l~~rGy~i~~la~~~~~le~Cylll 80 (413) T TIGR01798 1 NKEVELPIYSGTLGKDVIDIKKLYKNSGLFTFDPGFTSTASCESKITFIDGDKGILLYRGYPIDQLAEKSDYLEVCYLLL 80 (413) T ss_pred CCCCEEEECCCCCCCHHHHHHHHHHCCCCEEECCCCCEECCCCEEEEEEECCCCEEEECCCCHHHHHHCCCHHHHHHHHH T ss_conf 97510000134346204557778630674332355320022330357864675256544743788850133555556555 Q ss_pred CCCCCCHHHHHHHHHHHHHCCCCCHHHHHHHHHHCCCCCHHHHHHHHHHHHHHHHCCCCCCCCHHHHHHHHHHHHHHHHH Q ss_conf 18799989999999988640689989999998512476525789999999875206855767878898889999999999 Q gi|254780355|r 91 HGELANVSQQKDFNDKISRHALLNENMSRFFMGFPSSAHPMAMLVSAVGALSSFYYSPSGVQDLEQCVNVSLRMIAKIST 170 (429) Q Consensus 91 ~GeLPt~~el~~F~~~l~~~~~lpe~v~~~i~~~p~~ahPM~~L~~~vsaL~a~~~~~~~~~d~~~~~~~a~rLiA~~p~ 170 (429) T Consensus 81 ~~~~P~~~~~~~f~~~~~~ht~v~~q~~~~~~~f~~dahPma~~~~~~Gal~afy~~~~~i~~~~~r~~~~~rl~~k~Pt 160 (413) T TIGR01798 81 NGELPTKEQKDEFDDKVKEHTMVHEQLTRFFRGFRRDAHPMAVMVGVVGALSAFYHDALDINDPKHREIAAIRLIAKIPT 160 (413) T ss_pred HCCCCCHHHHHHHHHHHHHHHHHHHHHHHHHHHHCCCCCHHHHHHHHHHHHHHHHHHHHCCCCHHHHHHHHHHHHHHHHH T ss_conf 14788556789999999987899999999999731135347889999988998764432012134568999999874368 Q ss_pred HHHHHHHHHCCCCCCCCCCCHHHHHHHHHHHCCCCCCCC-CCCHHHHHHHHHHHHEECCCCCCCHHHHHHHHHCCCCCHH Q ss_conf 999999972798534888642468877876428984101-4796999998756350136787630155554420565424 Q gi|254780355|r 171 IAAMIYKYSIGQPFVYPRSDLDYASNFLHMCFSVPCAEY-QVNPLLARAMNRIFILHADHEQNASTSTVRLAGSSGADPF 249 (429) Q Consensus 171 i~A~~yr~~~G~~~i~Pd~~lsyaeNfL~Ml~~~~~~~~-~~~~~~~~ald~~LILhADHe~NaSTft~R~vaSt~adly 249 (429) T Consensus 161 ~~a~~y~y~~G~P~~yP~~~l~y~~nfl~m~f~~~~~~~~~~~P~l~~a~d~i~~lhadheqnast~tvr~aGs~~~nP~ 240 (413) T TIGR01798 161 LAAMSYKYSIGQPFVYPRNDLSYAENFLHMMFATPCEEYYKVNPVLARALDRIFILHADHEQNASTSTVRLAGSSGANPF 240 (413) T ss_pred HHHHHHHHCCCCCCCCCHHHHHHHHHHHHHHHHCCCCCCCCCCHHHHHHHHHHHHHCCCCCCCCCCCEEEECCCCCCCHH T ss_conf 88876632168853152144568889999876033222224561689875455112023111233222453146676437 Q ss_pred HHHHHHHHHHHHHHHCCCCHHHHHHHHHCCCCCHHHHHHHHHHHCCCCCEEECCCCCCCCCCCHHHHHHHHHHHHHHHHC Q ss_conf 67767554210022203528999998621553512799999982147861430277435555403468999999988860 Q gi|254780355|r 250 ACIAAGVACLGGRAHGGANEEALNMLMEIGSLERIPHYIMRAKDKNDPFRIMGFGHRVYRNHDPRCRIMRETMYEVLEVT 329 (429) Q Consensus 250 sai~agi~aL~GPlHGGAne~v~~ml~~I~~~~~v~~~i~~~~~~~~~~ri~GfGHrvyk~~DPRa~~l~~~~~~l~~~~ 329 (429) T Consensus 241 a~i~aGi~~lWG~ahGGanea~l~ml~~i~~~~~~~~~~~~~k~~~~~~~lmGfGhrvy~n~dPra~~~~~~C~~vl~~~ 320 (413) T TIGR01798 241 ACIAAGIAALWGPAHGGANEAVLKMLEEIGSVEKIAEFIKKVKDKNDEVRLMGFGHRVYKNYDPRAKVMRETCHEVLKEL 320 (413) T ss_pred HHHHHHHHHHCCCCCCCHHHHHHHHHHHHCCHHHHHHHHHHHHCCCCCEEEEEECHHHHCCCCHHHHHHHHHHHHHHHHH T ss_conf 88886577630466774568999999852027789999999740346635553021312047827899999999999972 Q ss_pred CCCCCHHHHHHHHHHHHHHHHHHCCCCCCCCCCCHHHHHHHHHCCCCHHHHHHHHHHHHHHHHHHHHHHHHHCCCCCCCC Q ss_conf 87765179999999999961153145798778447889999984999668589999999989999999997078983004 Q gi|254780355|r 330 GRFNDPIAQVAIELERIALEDEYFIERKLYPNVDFYSGITLRALGFPTNLFTVLFAVARTAGWVSQWTEMIVDPSRRIGR 409 (429) Q Consensus 330 ~~~~~~~~~~a~~le~~a~~d~~~~~r~l~pNvDfysg~i~~~lGip~~~ft~iFa~~R~~Gw~AH~~Eq~~~~~~ri~R 409 (429) T Consensus 321 G~~~~~~~~~a~~le~ial~d~yf~~~klyPnvdfysG~~~~a~G~P~~mft~~fal~r~vGWi~~W~em~~~~~~~~~r 400 (413) T TIGR01798 321 GKEDDPLLKLALELEKIALEDDYFIERKLYPNVDFYSGIILKALGIPTEMFTVIFALARTVGWISHWSEMISDPEQKIGR 400 (413) T ss_pred CCCCCHHHHHHHHHHHHHCCCCHHHHCCCCCCCHHHHHHHHHHHCCCHHHHHHHHHHHHHHHHHHHHHHHHCCCCHHCCC T ss_conf 33320578899889876305620100024666114666898861574689999999985444688788863164001025 Q ss_pred CCCCCCCCCCCCC Q ss_conf 5621058876870 Q gi|254780355|r 410 PRQLYTGALKRDY 422 (429) Q Consensus 410 P~~~Y~G~~~r~y 422 (429) T Consensus 401 Prqly~G~~~r~~ 413 (413) T TIGR01798 401 PRQLYTGEEKRDV 413 (413) T ss_pred CHHHHCCCHHCCC T ss_conf 2455346221169

HHsearch alignment for GI: 254780355 and conserved domain: TIGR01798