>gnl|CDD|99864 cd06111, DsCS_like, Cold-active citrate synthase (CS) from an Antarctic bacterial strain DS2-3R (Ds)-like. CS catalyzes the condensation of acetyl coenzyme A (AcCoA) and oxalacetate (OAA) to form citrate and coenzyme A (CoA), the first step in the citric acid cycle (TCA or Krebs cycle). 2-methylcitrate synthase (2MCS) catalyzes the condensation of propionyl-coenzyme A (PrCoA) and OAA to form 2-methylcitrate and coenzyme A (CoA) during propionate metabolism. The overall CS reaction is thought to proceed through three partial reactions: 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. DsCS, compared with CS from the hyperthermophile Pyrococcus furiosus (not included in this group), has an increase in the size of surface loops, a higher proline content in the loop regions, a more accessible active site, and a higher number of intramolecular ion pairs. 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. For example, included in this group are Corynebacterium glutamicum (Cg) PrpC1 and -2, which are only synthesized during growth on propionate-containing medium, can use PrCoA, AcCoA and butyryl-CoA as substrates, and have comparable catalytic activity with AcCoA as the major CgCS (GltA, not included in this group).. Length = 362

 Score =  257 bits (659), Expect = 3e-69
 Identities = 116/357 (32%), Positives = 182/357 (50%), Gaps = 19/357 (5%)

Query: 66  LLYRGYPIEQLSEKSDFLEVCYLLLHGELANVSQQKDFNDKISRHALLNENMSRFFMGFP 125
           L YRGYP++ L+E   F EV YLL +GEL N +Q  +F+ +   +  L+ N+       P
Sbjct: 23  LTYRGYPVQDLAENCSFEEVAYLLWNGELPNAAQLAEFSQRERSYRRLDRNLLSLIASLP 82

Query: 126 SSAHPMAMLVSAVGALSSFYYSPSGVQDLEQCVNVSLRMIAKISTIAAMIYKYSIGQPFV 185
            + HPM +L +AV  L +           +  +  ++R++A++ T+ A   +   G   +
Sbjct: 83  KNCHPMDVLRTAVSVLGAEDSETD-DSSPDANLAKAIRLLAQLPTVVAADIRRRKGLDPI 141

Query: 186 YPRSDLDYASNFLHMCF-SVPCAEYQVNPLLARAMNRIFILHADHEQNASTSTVRLAGSS 244
            P SDL  A NFLHMCF  VP      +P + RA +   IL+A+H  NAST T R+  S+
Sbjct: 142 PPDSDLGIAENFLHMCFGEVP------SPEVVRAFDVSLILYAEHSFNASTFTARVITST 195

Query: 245 GADPFACIAAGVACLGGRAHGGANEEALNMLMEIGSLERIPHYIMRAKDKNDPFRIMGFG 304
            +D ++ I   +  L G  HGGANE  ++M++EI   E+   +++ A  + +  ++MGFG
Sbjct: 196 LSDIYSAITGAIGALKGPLHGGANEAVMHMMLEIDDPEKAAQWMLDALARKE--KVMGFG 253

Query: 305 HRVYRNHDPRCRIMRETMYEVLEVTGRFNDPIAQVAIELERIALEDEYFIERKLYPNVDF 364
           HRVY++ D R   M + +  V  V         Q  + +    LED     + + PN+DF
Sbjct: 254 HRVYKSGDSRVPTMEKALRRVAAVHD------GQKWLAMYDA-LEDAMVAAKGIKPNLDF 306

Query: 365 YSGITLRALGFPTNLFTVLFAVARTAGWVSQWTEMIVDPSRRIGRPRQLYTGALKRD 421
            +G     +GF  + FT +F +AR  GW +   E   D    + RP   Y G  +R 
Sbjct: 307 PAGPAYYLMGFDIDFFTPIFVMARITGWTAHIMEQRAD--NALIRPLSEYNGPEQRP 361