HYDRA_RHIML
ID HYDRA_RHIML Reviewed; 241 AA.
AC Q6TMG4;
DT 10-MAY-2017, integrated into UniProtKB/Swiss-Prot.
DT 16-NOV-2011, sequence version 1.
DT 25-MAY-2022, entry version 52.
DE RecName: Full=Hydantoin racemase {ECO:0000303|PubMed:14711700};
DE EC=5.1.99.5 {ECO:0000305|PubMed:14711700};
GN Name=hyuA {ECO:0000303|PubMed:14711700};
OS Rhizobium meliloti (Ensifer meliloti) (Sinorhizobium meliloti).
OC Bacteria; Proteobacteria; Alphaproteobacteria; Hyphomicrobiales;
OC Rhizobiaceae; Sinorhizobium/Ensifer group; Sinorhizobium.
OX NCBI_TaxID=382;
RN [1]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA], FUNCTION, CATALYTIC ACTIVITY,
RP BIOPHYSICOCHEMICAL PROPERTIES, ACTIVITY REGULATION, SUBSTRATE SPECIFICITY,
RP AND SUBUNIT.
RC STRAIN=CECT 4114;
RX PubMed=14711700; DOI=10.1128/aem.70.1.625-630.2004;
RA Martinez-Rodriguez S., Las Heras-Vazquez F.J., Mingorance-Cazorla L.,
RA Clemente-Jimenez J.M., Rodriguez-Vico F.;
RT "Molecular cloning, purification, and biochemical characterization of
RT hydantoin racemase from the legume symbiont Sinorhizobium meliloti CECT
RT 4114.";
RL Appl. Environ. Microbiol. 70:625-630(2004).
RN [2]
RP MUTAGENESIS OF CYS-76 AND CYS-181.
RC STRAIN=CECT 4114;
RX PubMed=17132860; DOI=10.1110/ps.062452106;
RA Martinez-Rodriguez S., Andujar-Sanchez M., Neira J.L.,
RA Clemente-Jimenez J.M., Jara-Perez V., Rodriguez-Vico F.,
RA Las Heras-Vazquez F.J.;
RT "Site-directed mutagenesis indicates an important role of cysteines 76 and
RT 181 in the catalysis of hydantoin racemase from Sinorhizobium meliloti.";
RL Protein Sci. 15:2729-2738(2006).
RN [3]
RP CRYSTALLIZATION.
RC STRAIN=CECT 4114;
RX PubMed=18097103; DOI=10.1107/s1744309107066122;
RA Martinez-Rodriguez S., Gonzalez-Ramirez L.A., Clemente-Jimenez J.M.,
RA Rodriguez-Vico F., Las Heras-Vazquez F.J., Gavira J.A., Garcia-Ruiz J.M.;
RT "Crystallization and preliminary crystallographic studies of an active-site
RT mutant hydantoin racemase from Sinorhizobium meliloti CECT4114.";
RL Acta Crystallogr. F 64:50-53(2008).
CC -!- FUNCTION: May be involved in the asymmetric conversion of racemic 5-
CC substituted hydantoins to the corresponding L-amino acids. Catalyzes
CC the racemization via enolization of D- and L-5-monosubstituted
CC hydantoins. It shows a slight preference for hydantoins with short
CC rather than long aliphatic side chains or those with aromatic rings.
CC {ECO:0000269|PubMed:14711700}.
CC -!- CATALYTIC ACTIVITY:
CC Reaction=a D-5-monosubstituted hydantoin = a L-5-monosubstituted
CC hydantoin; Xref=Rhea:RHEA:46624, ChEBI:CHEBI:86339,
CC ChEBI:CHEBI:86340; EC=5.1.99.5;
CC Evidence={ECO:0000305|PubMed:14711700};
CC -!- ACTIVITY REGULATION: Competitively inhibited by both D- and L-5-
CC (methylthioethyl)hydantoin. Strongly inhibited by Cu(2+), Hg(2+),
CC Pb(2+) and Zn(2+). The activity is twofold lower in the presence of
CC Mn(2+), Co(2+) and Ni(2+). {ECO:0000269|PubMed:14711700}.
CC -!- BIOPHYSICOCHEMICAL PROPERTIES:
CC Kinetic parameters:
CC KM=3.76 mM for D-5-isobutylhydantoin (D-IBH)
CC {ECO:0000269|PubMed:14711700};
CC KM=6.41 mM for L-5-isobutylhydantoin (L-IBH)
CC {ECO:0000269|PubMed:14711700};
CC KM=8.3 mM for L-5-benzylhydantoin (L-BH)
CC {ECO:0000269|PubMed:14711700};
CC KM=13.89 mM for D-5-benzylhydantoin (D-BH)
CC {ECO:0000269|PubMed:14711700};
CC KM=17.32 mM for L-5-ethylhydantoin (L-EH)
CC {ECO:0000269|PubMed:14711700};
CC Note=kcat is 6.42 sec(-1) for L-5-ethylhydantoin (L-EH) as substrate.
CC kcat is 3.24 sec(-1) for D-5-isobutylhydantoin (D-IBH) as substrate.
CC kcat is 2.29 sec(-1) for D-5-benzylhydantoin (D-BH) as substrate.
CC kcat is 2.12 sec(-1) for L-5-isobutylhydantoin (L-IBH) as substrate.
CC kcat is 1.94 sec(-1) for L-5-benzylhydantoin (L-BH) as substrate.
CC {ECO:0000269|PubMed:14711700};
CC pH dependence:
CC Optimum pH is 8.5. {ECO:0000269|PubMed:14711700};
CC Temperature dependence:
CC The activity is gradually lost at temperatures of more than 30
CC degrees Celsius. {ECO:0000269|PubMed:14711700};
CC -!- SUBUNIT: Homotetramer. {ECO:0000269|PubMed:14711700}.
CC -!- SIMILARITY: Belongs to the HyuE racemase family. {ECO:0000305}.
CC ---------------------------------------------------------------------------
CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms
CC Distributed under the Creative Commons Attribution (CC BY 4.0) License
CC ---------------------------------------------------------------------------
DR EMBL; AY393697; AAQ93382.1; -; Genomic_DNA.
DR RefSeq; WP_004434222.1; NZ_WISY01000131.1.
DR AlphaFoldDB; Q6TMG4; -.
DR SMR; Q6TMG4; -.
DR STRING; 382.DU99_14415; -.
DR GeneID; 61604058; -.
DR PATRIC; fig|382.52.peg.2934; -.
DR OMA; ITSNKEW; -.
DR GO; GO:0036348; F:hydantoin racemase activity; ISS:UniProtKB.
DR GO; GO:0036361; F:racemase activity, acting on amino acids and derivatives; IEA:InterPro.
DR GO; GO:0008652; P:cellular amino acid biosynthetic process; IEA:UniProtKB-KW.
DR InterPro; IPR015942; Asp/Glu/hydantoin_racemase.
DR InterPro; IPR001920; Asp/Glu_race.
DR Pfam; PF01177; Asp_Glu_race; 1.
DR SUPFAM; SSF53681; SSF53681; 1.
PE 1: Evidence at protein level;
KW Amino-acid biosynthesis; Isomerase.
FT CHAIN 1..241
FT /note="Hydantoin racemase"
FT /id="PRO_0000439848"
FT SITE 76
FT /note="Seems to be responsible for recognition and proton
FT retrieval of D-isomers"
FT /evidence="ECO:0000305|PubMed:17132860"
FT SITE 181
FT /note="Seems to be responsible for L-isomers recognition
FT and racemization"
FT /evidence="ECO:0000305|PubMed:17132860"
FT MUTAGEN 76
FT /note="C->A: The secondary and the tertiary structure are
FT not significantly affected."
FT /evidence="ECO:0000269|PubMed:17132860"
FT MUTAGEN 181
FT /note="C->A: The secondary and the tertiary structure are
FT not significantly affected."
FT /evidence="ECO:0000269|PubMed:17132860"
SQ SEQUENCE 241 AA; 25285 MW; 6A861A9ECEA13DAD CRC64;
MHIHLINPNS TASMTAQALE SALLVKHAHT HVSASNPTDT PASIEGGADE AMSVPGMLAE
IRQGEAQGVD AYVIACFDDP GLHAAREVAK GPVIGICQAA VQVAMTISRR FSVITTLPRS
VPIIEDLVSD YGAERHCRKV RAIDLPVLAL EEDPQRAERL LLKEIEIAKA EDGAEAIVLG
CAGMSSLCDR LQKATGVPVI DGVTAAVKMA EALLGAGYAT SKVNTYAYPR IKAAAGHKVC
A
