Reviewed, UniProtKB/Swiss-Prot P32232 (CBS_RAT)

Names and origin

Protein names

Recommended name:
    Cystathionine beta-synthase
    EC=4.2.1.22
Alternative name(s):
    Serine sulfhydrase
    Beta-thionase
    Hemoprotein H-450

Gene names

Name:

Cbs

Organism

Rattus norvegicus (Rat)

Taxonomic identifier

10116 [NCBI]

Taxonomic lineage

Eukaryota › Metazoa › Chordata › Craniata › Vertebrata › Euteleostomi › Mammalia › Eutheria › Euarchontoglires › Glires › Rodentia › Sciurognathi › Muroidea › Muridae › Murinae › Rattus

Protein attributes

Sequence length	561 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Evidence at protein level.

General annotation (Comments)

Catalytic activity	L-serine + L-homocysteine = L-cystathionine + H2O.
Cofactor	Pyridoxal phosphate.
Pathway	Amino-acid biosynthesis; L-cysteine biosynthesis; L-cysteine from L-homocysteine and L-serine: step 1/2.
Subunit structure	Homotetramer By similarity.
Subcellular location	Nucleus By similarity. Cytoplasm.
Tissue specificity	Expressed in liver, kidney and brain.
Post-translational modification	Binds covalently to a heme group through a thiolate ligand.
Sequence similarities	Belongs to the cysteine synthase/cystathionine beta-synthase family. Contains 1 CBS domain.

Ontologies

Keywords
Biological process	Amino-acid biosynthesis Cysteine biosynthesis
Cellular component	Cytoplasm Nucleus
Coding sequence diversity	Alternative splicing
Domain	CBS domain
Ligand	Heme Iron Metal-binding Pyridoxal phosphate
Molecular function	Lyase
PTM	Isopeptide bond Ubl conjugation
Technical term	Direct protein sequencing
Gene Ontology (GO)
Biological process	cysteine biosynthetic process from serine Traceable author statement. Source: RGD cysteine biosynthetic process via cystathionine Inferred from electronic annotation. Source: InterPro response to nutrient levels Inferred from expression pattern. Source: RGD transsulfuration Inferred from direct assay. Source: RGD
Cellular component	cytoplasm Inferred from electronic annotation. Source: UniProtKB-SubCell nucleus Inferred from electronic annotation. Source: UniProtKB-SubCell soluble fraction Inferred from direct assay. Source: RGD
Molecular function	cystathionine beta-synthase activity Inferred from direct assay. Source: RGD iron ion binding Inferred from electronic annotation. Source: UniProtKB-KW pyridoxal phosphate binding Traceable author statement. Source: RGD
Complete GO annotation...

Alternative products

This entry describes 4 isoforms produced by alternative splicing. [Align] [Select]

Isoform I (identifier: P32232-1)

This isoform has been chosen as the 'canonical' sequence. All positional information in this entry refers to it. This is also the sequence that appears in the downloadable versions of the entry.

Isoform II (identifier: P32232-4)

The sequence of this isoform is not available.

Isoform III (identifier: P32232-2)

The sequence of this isoform differs from the canonical sequence as follows:
     514-528: SRDQAWSGVVGGPTD → Y

Isoform IV (identifier: P32232-3)

The sequence of this isoform differs from the canonical sequence as follows:
     450-478: AILGMVTLGNMLSSLLAGKVRPSDEVCKV → LRQSKDICHPTKRHIIQAHGLRKVPDTEA
     479-561: Missing.

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Initiator methionine	1	1	Removed Ref.2
	Chain	2 – 561	560	Cystathionine beta-synthase		PRO_0000167134
Regions
	Domain	414 – 474	61	CBS
	Region	253 – 257	5	Pyridoxal phosphate binding By similarity
Sites
	Metal binding	49	1	Iron (heme axial ligand) By similarity
	Metal binding	62	1	Iron (heme axial ligand) By similarity
	Binding site	146	1	Pyridoxal phosphate By similarity
	Binding site	346	1	Pyridoxal phosphate By similarity
Amino acid modifications
	Modified residue	116	1	N6-(pyridoxal phosphate)lysine By similarity
	Cross-link	208		Glycyl lysine isopeptide (Lys-Gly) (interchain with G-Cter in SUMO) By similarity
Natural variations
	Alternative sequence	450 – 478	29	AILGM…EVCKV → LRQSKDICHPTKRHIIQAHG LRKVPDTEA in isoform IV.		VSP_001220
	Alternative sequence	479 – 561	83	Missing in isoform IV.		VSP_001221
	Alternative sequence	514 – 528	15	SRDQA…GGPTD → Y in isoform III.		VSP_001218
Experimental info
	Sequence conflict	415	1	L → P in BAA00883. Ref.2

Sequences

	Sequence		Length	Mass (Da)
	Isoform I [UniParc]. Last modified January 23, 2007. Version 3. Checksum: 0199FCAF492AE3A2	FASTA	561	61,455
	10 20 30 40 50 60 MPSGTSQCED GSAGCPQDLE VQPEKGQLEK GASGDKERVW ISPDTPSRCT WQLGRPMADS 70 80 90 100 110 120 PHYHTVPTKS PKILPDILRK IGNTPMVRIN RISKNAGLKC ELLAKCEFFN AGGSVKDRIS 130 140 150 160 170 180 LRMIEDAERA GTLKPGDTII EPTSGNTGIG LALAAAVKGY RCIIVMPEKM SMEKVDVLRA 190 200 210 220 230 240 LGAEIVRTPT NARFDSPESH VGVAWRLKNE IPNSHILDQY RNASNPLAHY DDTAEEILQQ 250 260 270 280 290 300 CDGKVDMLVA SAGTGGTITG IARKLKEKCP GCKIIGVDPE GSILAEPEEL NQTEQTAYEV 310 320 330 340 350 360 EGIGYDFIPT VLDRAVVDRW FKSNDDDSFA FARMLISQEG LLCGGSSGSA MAVAVKAAQE 370 380 390 400 410 420 LKEGQRCVVI LPDSVRNYMS KFLSDKWMLQ KGFMKEELSV KRPWWWHLRV QELSLSAPLT 430 440 450 460 470 480 VLPTVTCEHT IAILREKGFD QAPVVNESGA ILGMVTLGNM LSSLLAGKVR PSDEVCKVLY 490 500 510 520 530 540 KQFKPIHLTD TLGMLSHILE MDHFALVVHE QIQSRDQAWS GVVGGPTDRN NGVSSKQLMV 550 560 FGVVTAIDLL NFVAAREQTR K
	Isoform II (Sequence not available).	FASTA	–	–
	Isoform III. Checksum: A71FF5D43137A5E1	FASTA	547	60,104
	10 20 30 40 50 60 MPSGTSQCED GSAGCPQDLE VQPEKGQLEK GASGDKERVW ISPDTPSRCT WQLGRPMADS 70 80 90 100 110 120 PHYHTVPTKS PKILPDILRK IGNTPMVRIN RISKNAGLKC ELLAKCEFFN AGGSVKDRIS 130 140 150 160 170 180 LRMIEDAERA GTLKPGDTII EPTSGNTGIG LALAAAVKGY RCIIVMPEKM SMEKVDVLRA 190 200 210 220 230 240 LGAEIVRTPT NARFDSPESH VGVAWRLKNE IPNSHILDQY RNASNPLAHY DDTAEEILQQ 250 260 270 280 290 300 CDGKVDMLVA SAGTGGTITG IARKLKEKCP GCKIIGVDPE GSILAEPEEL NQTEQTAYEV 310 320 330 340 350 360 EGIGYDFIPT VLDRAVVDRW FKSNDDDSFA FARMLISQEG LLCGGSSGSA MAVAVKAAQE 370 380 390 400 410 420 LKEGQRCVVI LPDSVRNYMS KFLSDKWMLQ KGFMKEELSV KRPWWWHLRV QELSLSAPLT 430 440 450 460 470 480 VLPTVTCEHT IAILREKGFD QAPVVNESGA ILGMVTLGNM LSSLLAGKVR PSDEVCKVLY 490 500 510 520 530 540 KQFKPIHLTD TLGMLSHILE MDHFALVVHE QIQYRNNGVS SKQLMVFGVV TAIDLLNFVA AREQTRK
	Isoform IV. Checksum: 1E582906BBA255C5	FASTA	478	52,513
	10 20 30 40 50 60 MPSGTSQCED GSAGCPQDLE VQPEKGQLEK GASGDKERVW ISPDTPSRCT WQLGRPMADS 70 80 90 100 110 120 PHYHTVPTKS PKILPDILRK IGNTPMVRIN RISKNAGLKC ELLAKCEFFN AGGSVKDRIS 130 140 150 160 170 180 LRMIEDAERA GTLKPGDTII EPTSGNTGIG LALAAAVKGY RCIIVMPEKM SMEKVDVLRA 190 200 210 220 230 240 LGAEIVRTPT NARFDSPESH VGVAWRLKNE IPNSHILDQY RNASNPLAHY DDTAEEILQQ 250 260 270 280 290 300 CDGKVDMLVA SAGTGGTITG IARKLKEKCP GCKIIGVDPE GSILAEPEEL NQTEQTAYEV 310 320 330 340 350 360 EGIGYDFIPT VLDRAVVDRW FKSNDDDSFA FARMLISQEG LLCGGSSGSA MAVAVKAAQE 370 380 390 400 410 420 LKEGQRCVVI LPDSVRNYMS KFLSDKWMLQ KGFMKEELSV KRPWWWHLRV QELSLSAPLT 430 440 450 460 470 VLPTVTCEHT IAILREKGFD QAPVVNESGL RQSKDICHPT KRHIIQAHGL RKVPDTEA

References

[1]	"Rat cystathionine beta-synthase. Gene organization and alternative splicing." Swaroop M., Bradley K., Ohura T., Tahara T., Roper M.D., Rosenberg L.E., Kraus J.P. J. Biol. Chem. 267:11455-11461(1992) [PubMed: 1597473] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA], PARTIAL PROTEIN SEQUENCE. Tissue: Liver.
[2]	"Molecular cloning and sequence analysis of cDNA coding for rat liver hemoprotein H-450." Ishihara S., Morohashi K., Sadano H., Kawabata S., Gotoh O., Omura T. J. Biochem. 108:899-902(1990) [PubMed: 2089036] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA], PROTEIN SEQUENCE OF 2-23 AND 39-48. Strain: Sprague-Dawley. Tissue: Liver.
+	Additional computationally mapped references.

Cross-references

Sequence databases
EMBLGenBankDDBJ	M88344 mRNA. Translation: AAB02042.1. M88346 mRNA. Translation: AAA42024.1. D01098 mRNA. Translation: BAA00883.1.
IPI	IPI00214299. IPI00231548. IPI00231549.
PIR	A42790. C42790.
RefSeq	NP_036654.2.
UniGene	Rn.87853
3D structure databases
HSSP	HSSP built from PDB template 1JBQ based on UniProtKB P35520.
SMR	P32232. Positions 40-396.
ModBase	Search...
Protein-protein interaction databases
STRING	P32232.
Proteomic databases
PRIDE	P32232.
Genome annotation databases
Ensembl	ENSRNOT00000042432; ENSRNOP00000039968; ENSRNOG00000029528; Rattus norvegicus. [Genome view] ENSRNOT00000045275; ENSRNOP00000042958; ENSRNOG00000029528; Rattus norvegicus. [Genome view] ENSRNOT00000048219; ENSRNOP00000046652; ENSRNOG00000029528; Rattus norvegicus. [Genome view]
GeneID	24250.
KEGG	rno:24250.
Organism-specific databases
CTD	24250.
RGD	2287. Cbs.
Phylogenomic databases
HOVERGEN	P32232.
Enzyme and pathway databases
BioCyc	MetaCyc:MON-8583.
BRENDA	4.2.1.22. 248.
Gene expression databases
ArrayExpress	P32232.
Genevestigator	P32232.
GermOnline	ENSRNOG00000029528. Rattus norvegicus.
Family and domain databases
InterPro	IPR001216. Cys_synth_BS. IPR005857. Cysta_beta_synth. IPR000644. Cysta_beta_synth_core. IPR001926. PyrdxlP-dep_enz_bsu. [Graphical view]
Pfam	PF00571. CBS. 1 hit. PF00291. PALP. 1 hit. [Graphical view]
SMART	SM00116. CBS. 1 hit. [Graphical view]
TIGRFAMs	TIGR01137. cysta_beta. 1 hit.
PROSITE	PS51371. CBS. 1 hit. PS00901. CYS_SYNTHASE. 1 hit. [Graphical view]
ProtoNet	Search...
Other Resources
NextBio	602761.

Entry information

Entry name

CBS_RAT

Accession

Primary (citable) accession number: P32232

Entry history

Integrated into UniProtKB/Swiss-Prot:	October 1, 1993
Last sequence update:	January 23, 2007
Last modified:	October 13, 2009
This is version 92 of the entry and version 3 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

HPI (Human Proteome Initiative)