RPSBLAST alignment for GI: 254780355 and conserved domain: cd06105
>gnl|CDD|99858 cd06105, ScCit1-2_like, Saccharomyces cerevisiae (Sc) citrate synthases Cit1-2_like. Citrate synthases (CS) catalyzes the condensation of acetyl coenzyme A (AcCoA) with oxaloacetate (OAA) to form citrate and coenzyme A (CoA), the first step in the citric acid cycle (TCA or Krebs cycle). Some CS proteins function as 2-methylcitrate synthase (2MCS). 2MCS catalyzes the condensation of propionyl-coenzyme A (PrCoA) and OAA to form 2-methylcitrate and CoA during propionate metabolism. The overall CS reaction is thought to proceed through three partial reactions and involves both closed and open conformational forms of the enzyme: a) the carbanion or equivalent is generated from AcCoA by base abstraction of a proton, b) the nucleophilic attack of this carbanion on OAA to generate citryl-CoA, and c) the hydrolysis of citryl-CoA to produce citrate and CoA. There are two types of CSs: type I CS and type II CSs. Type I CSs are found in eukarya, gram-positive bacteria, archaea, and in some gram-negative bacteria and are homodimers with both subunits participating in the active site. Type II CSs are unique to gram-negative bacteria and are homohexamers of identical subunits (approximated as a trimer of dimers). ScCit1 is a nuclear-encoded mitochondrial CS with highly specificity for AcCoA. In addition to its CS function, ScCit1 plays a part in the construction of the TCA cycle metabolon. Yeast cells deleted for Cit1 are hyper-susceptible to apoptosis induced by heat and aging stress. ScCit2 is a peroxisomal CS involved in the glyoxylate cycle; in addition to having activity with AcCoA, it may have activity with PrCoA. Chicken and pig heart CS, two Arabidopsis thaliana (Ath) CSs, CSY4 and -5, and Aspergillus niger (An) CS also belong to this group. Ath CSY4 has a mitochondrial targeting sequence; AthCSY5 has no identifiable targeting sequence. AnCS encoded by the citA gene has both an N-terminal mitochondrial import signal and a C-terminal peroxisiomal target sequence; it is not known if both these signals are functional in vivo. This group contains proteins which functions exclusively as either a CS or a 2MCS, as well as those with relaxed specificity which have dual functions as both a CS and a 2MCS.. Length = 427
Score = 138 bits (350), Expect = 2e-33
Identities = 119/394 (30%), Positives = 186/394 (47%), Gaps = 54/394 (13%)
Query: 59 IDGNNGILLYRGYPIEQLSE---KSDFLE------VCYLLLHGELANVSQQKDFNDKISR 109
+D GI +RG I + + K+ E + +LLL GE+ Q + + +
Sbjct: 53 LDPEEGIR-FRGLSIPECQKLLPKAPGGEEPLPEGLFWLLLTGEVPTKEQVSALSKEWAA 111
Query: 110 HALLNENMSRFFMGFPSSAHPMAMLVSAVGAL---SSFY--YSPSGVQD---LEQCVNVS 161
A L ++ FP++ HPM+ L +A+ AL S F Y+ G+ E S
Sbjct: 112 RAALPSHVVTMLDNFPTNLHPMSQLSAAITALNSESKFAKAYA-EGIHKSKYWEYVYEDS 170
Query: 162 LRMIAKISTIAAMIYK--YSIGQPFVYPRSDLDYASNFLHMC-FSVPCAEYQVNPLLARA 218
+ +IAK+ +AA IY+ Y G+ + S+LD+++NF +M ++ +P
Sbjct: 171 MDLIAKLPCVAAKIYRNLYRGGK-IIAIDSNLDWSANFANMLGYT--------DPQFTEL 221
Query: 219 MNRIFILHADHEQ-NASTSTVRLAGSSGADPFACIAAGVACLGGRAHGGANEEALNMLM- 276
M +H+DHE N S T L GS+ +DP+ AA + L G HG AN+E L L
Sbjct: 222 MRLYLTIHSDHEGGNVSAHTTHLVGSALSDPYLSFAAAMNGLAGPLHGLANQEVLVWLTK 281
Query: 277 ---EIG---SLERIPHYIMRAKDKNDPFRIMGFGHRVYRNHDPRCRIMRETMYEVLEVTG 330
E+G S E++ Y+ K N + G+GH V R DPR RE + L
Sbjct: 282 LQKEVGKDVSDEQLREYVW--KTLNSGRVVPGYGHAVLRKTDPRYTCQREFALKHLP--- 336
Query: 331 RFNDPIAQVAIELERIALE--DEYFIERKLYPNVDFYSGITLRALGFP-TNLFTVLFAVA 387
NDP+ ++ +L +I E + +PNVD +SG+ L+ G N +TVLF V+
Sbjct: 337 --NDPLFKLVSQLYKIVPPVLTEQGKAKNPWPNVDAHSGVLLQYYGLTEMNYYTVLFGVS 394
Query: 388 RTAGWVSQ--WTEMIVDPSRRIGRPRQLYTGALK 419
R G +SQ W + P + RP+ + T L+
Sbjct: 395 RALGVLSQLIWDRALGLP---LERPKSVSTDGLE 425