Q96IY4 (CBPB2_HUMAN) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
Carboxypeptidase B2
EC=3.4.17.20

Alternative name(s):
Carboxypeptidase U
Short name=CPU
Plasma carboxypeptidase B
Short name=pCPB
Thrombin-activable fibrinolysis inhibitor
Short name=TAFI

Gene names

Name:

CPB2

Organism

Homo sapiens (Human)

Taxonomic identifier

9606 [NCBI]

Taxonomic lineage

Eukaryota › Metazoa › Chordata › Craniata › Vertebrata › Euteleostomi › Mammalia › Eutheria › Euarchontoglires › Primates › Haplorrhini › Catarrhini › Hominidae › Homo

Protein attributes

Sequence length	423 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)

Function	Cleaves C-terminal arginine or lysine residues from biologically active peptides such as kinins or anaphylatoxins in the circulation thereby regulating their activities. Down-regulates fibrinolysis by removing C-terminal lysine residues from fibrin that has already been partially degraded by plasmin. Ref.8
Catalytic activity	Release of C-terminal Arg and Lys from a polypeptide. Ref.8
Cofactor	Binds 1 zinc ion per subunit.
Enzyme regulation	TAFI/CPB2 is unique among carboxypeptidases in that it spontaneously inactivates with a short half-life, a property that is crucial for its role in controlling blood clot lysis. The zymogen is stabilized by interactions with the activation peptide. Release of the activation peptide increases a dynamic flap mobility and in time this leads to conformational changes that disrupt the catalytic site and expose a cryptic thrombin-cleavage site present at Arg-324. Ref.12
Subcellular location	Secreted.
Tissue specificity	Plasma; synthesized in the liver.
Sequence similarities	Belongs to the peptidase M14 family.

Ontologies

Keywords
Biological process	Blood coagulation Fibrinolysis
Cellular component	Secreted
Coding sequence diversity	Alternative splicing Polymorphism
Domain	Signal
Ligand	Metal-binding Zinc
Molecular function	Carboxypeptidase Hydrolase Metalloprotease Protease
PTM	Disulfide bond Glycoprotein Zymogen
Technical term	3D-structure Complete proteome Direct protein sequencing Reference proteome
Gene Ontology (GO)
Biological process	blood coagulation Inferred from electronic annotation. Source: UniProtKB-KW fibrinolysis Inferred from electronic annotation. Source: UniProtKB-KW proteolysis Traceable author statement. Source: ProtInc
Cellular component	extracellular space Traceable author statement. Source: ProtInc
Molecular function	metallocarboxypeptidase activity Traceable author statement. Source: ProtInc zinc ion binding Inferred from electronic annotation. Source: InterPro
Complete GO annotation...

Alternative products

This entry describes 2 isoforms produced by alternative splicing. [Align] [Select]

Isoform 1 (identifier: Q96IY4-1)

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 2 (identifier: Q96IY4-2)

The sequence of this isoform differs from the canonical sequence as follows:
     198-234: Missing.
     384-423: IELRDTGTYGFLLPERYIKPTCREAFAAVSKIAWHVIRNV → SNPPVEKLLPLSLK

Sequence annotation (Features)

Feature key

Position(s)

Length

Description

Graphical view

Feature identifier

Molecule processing

Signal peptide

1 – 22

22

Potential

Propeptide

23 – 114

92

Activation peptide

PRO_0000004377

Chain

115 – 423

309

Carboxypeptidase B2

PRO_0000004378

Sites

Active site

385

1

Nucleophile Ref.12

Metal binding

181

1

Zinc; catalytic

Metal binding

184

1

Zinc; catalytic

Metal binding

310

1

Zinc; catalytic

Site

324 – 325

2

Cleavage; by thrombin

Amino acid modifications

Glycosylation

44

1

N-linked (GlcNAc...) Ref.9 Ref.10 Ref.12

Glycosylation

73

1

N-linked (GlcNAc...) Ref.9 Ref.10 Ref.12

Glycosylation

85

1

N-linked (GlcNAc...) Ref.10 Ref.12

Glycosylation

108

1

N-linked (GlcNAc...) Ref.9 Ref.10 Ref.11 Ref.12

Glycosylation

241

1

N-linked (GlcNAc...); partial Ref.10

Disulfide bond

178 ↔ 191

Ref.10 Ref.12 Ref.13

Disulfide bond

250 ↔ 274

Ref.10 Ref.12 Ref.13

Disulfide bond

265 ↔ 279

Ref.10 Ref.12 Ref.13

Natural variations

Alternative sequence

198 – 234

37

Missing in isoform 2.

VSP_013446

Alternative sequence

384 – 423

40

IELRD…VIRNV → SNPPVEKLLPLSLK in isoform 2.

VSP_013447

Natural variant

169

1

A → T. Ref.1 Ref.4
Corresponds to variant rs3742264 [ dbSNP | Ensembl ].

VAR_032565

Natural variant

347

1

I → T. Ref.1 Ref.3 Ref.4 Ref.5 Ref.7
Corresponds to variant rs1926447 [ dbSNP | Ensembl ].

VAR_022258

Experimental info

Sequence conflict

25

1

S → T in BAA90475. Ref.2

Secondary structure

1

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423

Helix Strand Turn

Details...

Beta strand

28 – 31

4

Helix

36 – 48

13

Beta strand

49 – 58

10

Helix

59 – 61

3

Beta strand

68 – 72

5

Helix

74 – 86

13

Beta strand

91 – 96

6

Helix

98 – 107

10

Helix

108 – 110

3

Helix

118 – 121

4

Helix

126 – 139

14

Turn

141 – 143

3

Beta strand

144 – 148

5

Beta strand

159 – 163

5

Beta strand

173 – 177

5

Helix

186 – 194

9

Helix

198 – 201

4

Helix

208 – 214

7

Beta strand

216 – 221

6

Helix

229 – 233

5

Helix

255 – 257

3

Turn

262 – 265

4

Beta strand

270 – 272

3

Helix

287 – 299

13

Turn

300 – 302

3

Beta strand

303 – 310

8

Beta strand

315 – 317

3

Helix

330 – 347

18

Helix

371 – 375

5

Beta strand

380 – 385

6

Helix

398 – 400

3

Helix

401 – 422

22

Sequences

	Sequence		Length	Mass (Da)
	Isoform 1 [UniParc]. Last modified January 11, 2011. Version 2. Checksum: B4D20E03ECDD55EF	FASTA	423	48,424
	10 20 30 40 50 60 MKLCSLAVLV PIVLFCEQHV FAFQSGQVLA ALPRTSRQVQ VLQNLTTTYE IVLWQPVTAD 70 80 90 100 110 120 LIVKKKQVHF FVNASDVDNV KAHLNVSGIP CSVLLADVED LIQQQISNDT VSPRASASYY 130 140 150 160 170 180 EQYHSLNEIY SWIEFITERH PDMLTKIHIG SSFEKYPLYV LKVSGKEQAA KNAIWIDCGI 190 200 210 220 230 240 HAREWISPAF CLWFIGHITQ FYGIIGQYTN LLRLVDFYVM PVVNVDGYDY SWKKNRMWRK 250 260 270 280 290 300 NRSFYANNHC IGTDLNRNFA SKHWCEEGAS SSSCSETYCG LYPESEPEVK AVASFLRRNI 310 320 330 340 350 360 NQIKAYISMH SYSQHIVFPY SYTRSKSKDH EELSLVASEA VRAIEKISKN TRYTHGHGSE 370 380 390 400 410 420 TLYLAPGGGD DWIYDLGIKY SFTIELRDTG TYGFLLPERY IKPTCREAFA AVSKIAWHVI RNV
	Isoform 2 [UniParc]. Checksum: 2C011F6D4265F4B8	FASTA	360	40,922
	10 20 30 40 50 60 MKLCSLAVLV PIVLFCEQHV FAFQSGQVLA ALPRTSRQVQ VLQNLTTTYE IVLWQPVTAD 70 80 90 100 110 120 LIVKKKQVHF FVNASDVDNV KAHLNVSGIP CSVLLADVED LIQQQISNDT VSPRASASYY 130 140 150 160 170 180 EQYHSLNEIY SWIEFITERH PDMLTKIHIG SSFEKYPLYV LKVSGKEQAA KNAIWIDCGI 190 200 210 220 230 240 HAREWISPAF CLWFIGHNRM WRKNRSFYAN NHCIGTDLNR NFASKHWCEE GASSSSCSET 250 260 270 280 290 300 YCGLYPESEP EVKAVASFLR RNINQIKAYI SMHSYSQHIV FPYSYTRSKS KDHEELSLVA 310 320 330 340 350 360 SEAVRAIEKI SKNTRYTHGH GSETLYLAPG GGDDWIYDLG IKYSFTSNPP VEKLLPLSLK

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"Isolation, molecular cloning, and partial characterization of a novel carboxypeptidase B from human plasma." Eaton D.L., Malloy B.E., Tsai S.P., Henzel W., Drayna D. J. Biol. Chem. 266:21833-21838(1991) [PubMed: 1939207] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1), PARTIAL PROTEIN SEQUENCE, INTERACTION WITH PLASMINOGEN, VARIANTS THR-169 AND THR-347. Tissue: Liver.
[2]	"Isolation, molecular cloning, and partial characterization of a novel carboxypeptidase B from human plasma." Matsumoto A. Submitted (MAR-1998) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 2).
[3]	"Cloning of human full-length CDSs in BD Creator(TM) system donor vector." Kalnine N., Chen X., Rolfs A., Halleck A., Hines L., Eisenstein S., Koundinya M., Raphael J., Moreira D., Kelley T., LaBaer J., Lin Y., Phelan M., Farmer A. Submitted (MAY-2003) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1), VARIANT THR-347.
[4]	"Complete sequencing and characterization of 21,243 full-length human cDNAs." Ota T., Suzuki Y., Nishikawa T., Otsuki T., Sugiyama T., Irie R., Wakamatsu A., Hayashi K., Sato H., Nagai K., Kimura K., Makita H., Sekine M., Obayashi M., Nishi T., Shibahara T., Tanaka T., Ishii S. , Yamamoto J., Saito K., Kawai Y., Isono Y., Nakamura Y., Nagahari K., Murakami K., Yasuda T., Iwayanagi T., Wagatsuma M., Shiratori A., Sudo H., Hosoiri T., Kaku Y., Kodaira H., Kondo H., Sugawara M., Takahashi M., Kanda K., Yokoi T., Furuya T., Kikkawa E., Omura Y., Abe K., Kamihara K., Katsuta N., Sato K., Tanikawa M., Yamazaki M., Ninomiya K., Ishibashi T., Yamashita H., Murakawa K., Fujimori K., Tanai H., Kimata M., Watanabe M., Hiraoka S., Chiba Y., Ishida S., Ono Y., Takiguchi S., Watanabe S., Yosida M., Hotuta T., Kusano J., Kanehori K., Takahashi-Fujii A., Hara H., Tanase T.-O., Nomura Y., Togiya S., Komai F., Hara R., Takeuchi K., Arita M., Imose N., Musashino K., Yuuki H., Oshima A., Sasaki N., Aotsuka S., Yoshikawa Y., Matsunawa H., Ichihara T., Shiohata N., Sano S., Moriya S., Momiyama H., Satoh N., Takami S., Terashima Y., Suzuki O., Nakagawa S., Senoh A., Mizoguchi H., Goto Y., Shimizu F., Wakebe H., Hishigaki H., Watanabe T., Sugiyama A., Takemoto M., Kawakami B., Yamazaki M., Watanabe K., Kumagai A., Itakura S., Fukuzumi Y., Fujimori Y., Komiyama M., Tashiro H., Tanigami A., Fujiwara T., Ono T., Yamada K., Fujii Y., Ozaki K., Hirao M., Ohmori Y., Kawabata A., Hikiji T., Kobatake N., Inagaki H., Ikema Y., Okamoto S., Okitani R., Kawakami T., Noguchi S., Itoh T., Shigeta K., Senba T., Matsumura K., Nakajima Y., Mizuno T., Morinaga M., Sasaki M., Togashi T., Oyama M., Hata H., Watanabe M., Komatsu T., Mizushima-Sugano J., Satoh T., Shirai Y., Takahashi Y., Nakagawa K., Okumura K., Nagase T., Nomura N., Kikuchi H., Masuho Y., Yamashita R., Nakai K., Yada T., Nakamura Y., Ohara O., Isogai T., Sugano S. Nat. Genet. 36:40-45(2004) [PubMed: 14702039] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1), VARIANTS THR-169 AND THR-347. Tissue: Liver.
[5]	SeattleSNPs variation discovery resource Submitted (AUG-2004) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA], VARIANT THR-347.
[6]	"The DNA sequence and analysis of human chromosome 13." Dunham A., Matthews L.H., Burton J., Ashurst J.L., Howe K.L., Ashcroft K.J., Beare D.M., Burford D.C., Hunt S.E., Griffiths-Jones S., Jones M.C., Keenan S.J., Oliver K., Scott C.E., Ainscough R., Almeida J.P., Ambrose K.D., Andrews D.T. , Ashwell R.I.S., Babbage A.K., Bagguley C.L., Bailey J., Bannerjee R., Barlow K.F., Bates K., Beasley H., Bird C.P., Bray-Allen S., Brown A.J., Brown J.Y., Burrill W., Carder C., Carter N.P., Chapman J.C., Clamp M.E., Clark S.Y., Clarke G., Clee C.M., Clegg S.C., Cobley V., Collins J.E., Corby N., Coville G.J., Deloukas P., Dhami P., Dunham I., Dunn M., Earthrowl M.E., Ellington A.G., Faulkner L., Frankish A.G., Frankland J., French L., Garner P., Garnett J., Gilbert J.G.R., Gilson C.J., Ghori J., Grafham D.V., Gribble S.M., Griffiths C., Hall R.E., Hammond S., Harley J.L., Hart E.A., Heath P.D., Howden P.J., Huckle E.J., Hunt P.J., Hunt A.R., Johnson C., Johnson D., Kay M., Kimberley A.M., King A., Laird G.K., Langford C.J., Lawlor S., Leongamornlert D.A., Lloyd D.M., Lloyd C., Loveland J.E., Lovell J., Martin S., Mashreghi-Mohammadi M., McLaren S.J., McMurray A., Milne S., Moore M.J.F., Nickerson T., Palmer S.A., Pearce A.V., Peck A.I., Pelan S., Phillimore B., Porter K.M., Rice C.M., Searle S., Sehra H.K., Shownkeen R., Skuce C.D., Smith M., Steward C.A., Sycamore N., Tester J., Thomas D.W., Tracey A., Tromans A., Tubby B., Wall M., Wallis J.M., West A.P., Whitehead S.L., Willey D.L., Wilming L., Wray P.W., Wright M.W., Young L., Coulson A., Durbin R.M., Hubbard T., Sulston J.E., Beck S., Bentley D.R., Rogers J., Ross M.T. Nature 428:522-528(2004) [PubMed: 15057823] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
[7]	"The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)." The MGC Project Team Genome Res. 14:2121-2127(2004) [PubMed: 15489334] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1), VARIANT THR-347. Tissue: Skeletal muscle.
[8]	"Characterization of plasmin-mediated activation of plasma procarboxypeptidase B. Modulation by glycosaminoglycans." Mao S.S., Cooper C.M., Wood T., Shafer J.A., Gardell S.J. J. Biol. Chem. 274:35046-35052(1999) [PubMed: 10574983] [Abstract] Cited for: FUNCTION, CATALYTIC ACTIVITY.
[9]	"Human plasma N-glycoproteome analysis by immunoaffinity subtraction, hydrazide chemistry, and mass spectrometry." Liu T., Qian W.-J., Gritsenko M.A., Camp D.G. II, Monroe M.E., Moore R.J., Smith R.D. J. Proteome Res. 4:2070-2080(2005) [PubMed: 16335952] [Abstract] Cited for: GLYCOSYLATION [LARGE SCALE ANALYSIS] AT ASN-44; ASN-73 AND ASN-108, MASS SPECTROMETRY. Tissue: Plasma.
[10]	"Post-translational modifications of human thrombin-activatable fibrinolysis inhibitor (TAFI): evidence for a large shift in the isoelectric point and reduced solubility upon activation." Valnickova Z., Christensen T., Skottrup P., Thogersen I.B., Hojrup P., Enghild J.J. Biochemistry 45:1525-1535(2006) [PubMed: 16445295] [Abstract] Cited for: GLYCOSYLATION AT ASN-44; ASN-73; ASN-85; ASN-108 AND ASN-241, DISULFIDE BONDS.
[11]	"Glycoproteomics analysis of human liver tissue by combination of multiple enzyme digestion and hydrazide chemistry." Chen R., Jiang X., Sun D., Han G., Wang F., Ye M., Wang L., Zou H. J. Proteome Res. 8:651-661(2009) [PubMed: 19159218] [Abstract] Cited for: GLYCOSYLATION [LARGE SCALE ANALYSIS] AT ASN-108, MASS SPECTROMETRY. Tissue: Liver.
[12]	"Crystal structures of TAFI elucidate the inactivation mechanism of activated TAFI: a novel mechanism for enzyme autoregulation." Marx P.F., Brondijk T.H., Plug T., Romijn R.A., Hemrika W., Meijers J.C., Huizinga E.G. Blood 112:2803-2809(2008) [PubMed: 18559974] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.8 ANGSTROMS) OF 24-423 ALONE AND IN COMPLEX WITH INHIBITOR, GLYCOSYLATION AT ASN-44; ASN-73; ASN-85 AND ASN-108, ACTIVE SITE, ZINC-BINDING SITES, ENZYME REGULATION, DISULFIDE BONDS.
[13]	"Insights into the molecular inactivation mechanism of human activated thrombin-activatable fibrinolysis inhibitor." Sanglas L., Arolas J.L., Valnickova Z., Aviles F.X., Enghild J.J., Gomis-Ruth F.X. J. Thromb. Haemost. 8:1056-1065(2010) [PubMed: 20088943] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.5 ANGSTROMS) OF 115-423 IN COMPLEX WITH INHIBITOR, DISULFIDE BONDS.
+	Additional computationally mapped references.

Web resources

SeattleSNPs

Cross-references

Sequence databases

EMBL
GenBank
DDBJ

M75106 mRNA. Translation: AAA60042.1.
AB011969 mRNA. Translation: BAA90475.1.
BT006936 mRNA. Translation: AAP35582.1.
AK290829 mRNA. Translation: BAF83518.1.
AY714780 Genomic DNA. Translation: AAT97987.1.
AL157758, AL137141 Genomic DNA. Translation: CAI10904.1.
AL157758, AL137141 Genomic DNA. Translation: CAI10905.1.
AL137141, AL157758 Genomic DNA. Translation: CAI12170.1.
AL137141, AL157758 Genomic DNA. Translation: CAI12171.1.
BC007057 mRNA. Translation: AAH07057.1.

IPI

IPI00293057.
IPI00329775.

PIR

A41204.

RefSeq

NP_001863.2. NM_001872.3.
NP_057497.3. NM_016413.3.

UniGene

Hs.512937.

3D structure databases

PDBe
RCSB PDB
PDBj

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
3D66	X-ray	3.10	A/B/C	24-423	[»]
3D67	X-ray	3.40	A/B/C	24-423	[»]
3D68	X-ray	2.80	A/B/C	24-423	[»]
3LMS	X-ray	2.50	A	115-423	[»]

ProteinModelPortal

Q96IY4.

SMR

Q96IY4. Positions 24-423.

ModBase

Search...

Protein-protein interaction databases

IntAct

Q96IY4. 1 interaction.

STRING

Q96IY4.

Protein family/group databases

MEROPS

M14.009.

PTM databases

PhosphoSite

Q96IY4.

Polymorphism databases

DMDM

62899885.

Proteomic databases

PRIDE

Q96IY4.

Protocols and materials databases

StructuralBiologyKnowledgebase

Search...

Genome annotation databases

Ensembl

ENST00000181383; ENSP00000181383; ENSG00000080618.

GeneID

1361.

KEGG

hsa:1361.

UCSC

uc001vaw.1. human.
uc001vax.1. human.

Organism-specific databases

CTD

1361.

GeneCards

GC13M046627.

HGNC

HGNC:2300. CPB2.

HPA

HPA004146.

MIM

603101. gene.

neXtProt

NX_Q96IY4.

PharmGKB

PA26822.

GenAtlas

Search...

Phylogenomic databases

eggNOG

prNOG09285.

GeneTree

ENSGT00560000077118.

HOGENOM

HBG445627.

HOVERGEN

HBG050815.

InParanoid

Q96IY4.

OMA

EIYSWIE.

OrthoDB

EOG4NKBVH.

PhylomeDB

Q96IY4.

Gene expression databases

ArrayExpress

Q96IY4.

Bgee

Q96IY4.

CleanEx

HS_CPB2.

Genevestigator

Q96IY4.

GermOnline

ENSG00000080618. Homo sapiens.

Family and domain databases

InterPro

IPR000834. Peptidase_M14.
IPR003146. Prot_inh_M14A.
IPR009020. Prot_inh_propept.
[Graphical view]

Gene3D

G3DSA:3.30.70.340. G3DSA:3.30.70.340. 1 hit.

KO

K01300.

Pfam

PF00246. Peptidase_M14. 1 hit.
PF02244. Propep_M14. 1 hit.
[Graphical view]

PRINTS

PR00765. CRBOXYPTASEA.

SMART

SM00631. Zn_pept. 1 hit.
[Graphical view]

SUPFAM

SSF54897. Prot_inh_propept. 1 hit.

PROSITE

PS00132. CARBOXYPEPT_ZN_1. False negative.
PS00133. CARBOXYPEPT_ZN_2. False negative.
[Graphical view]

ProtoNet

Search...

Other

NextBio

5513.

SOURCE

Search...

Entry information

Entry name

CBPB2_HUMAN

Accession

Primary (citable) accession number: Q96IY4
Secondary accession number(s): A8K464 , Q15114, Q5T9K1, Q5T9K2, Q9P2Y6

Entry history

Integrated into UniProtKB/Swiss-Prot:	April 26, 2005
Last sequence update:	January 11, 2011
Last modified:	January 25, 2012
This is version 92 of the entry and version 2 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Chordata Protein Annotation Program

Disclaimer

Any medical or genetic information present in this entry is provided for research, educational and informational purposes only. It is not in any way intended to be used as a substitute for professional medical advice, diagnosis, treatment or care.