Reviewed, UniProtKB/Swiss-Prot P00918 (CAH2_HUMAN)

Names and origin

Protein names

Recommended name:
    Carbonic anhydrase 2
    EC=4.2.1.1
Alternative name(s):
    Carbonic anhydrase II
      Short name=CA-II
    Carbonate dehydratase II
    Carbonic anhydrase C
      Short name=CAC

Gene names

Name:

CA2

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	260 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	Essential for bone resorption and osteoclast differentiation By similarity. Reversible hydration of carbon dioxide.
Catalytic activity	H(2)CO(3) = CO(2) + H(2)O.
Cofactor	Zinc.
Subunit structure	Interacts with SLC4A4. Interaction with SLC4A7 regulates SLC4A7 transporter activity.
Subcellular location	Cytoplasm.
Involvement in disease	Defects in CA2 are the cause of autosomal recessive osteopetrosis type 3 (OPTB3) [MIM:259730]; also known as osteopetrosis with renal tubular acidosis, carbonic anhydrase II deficiency syndrome, Guibaud-Vainsel syndrome or marble brain disease. Osteopetrosis is a rare genetic disease characterized by abnormally dense bone, due to defective resorption of immature bone. The disorder occurs in two forms: a severe autosomal recessive form occurring in utero, infancy, or childhood, and a benign autosomal dominant form occurring in adolescence or adulthood. Autosomal recessive osteopetrosis is usually associated with normal or elevated amount of non-functional osteoclasts. OPTB3 is associated with renal tubular acidosis, cerebral calcification (marble brain disease) and in some cases with mental retardation.
Sequence similarities	Belongs to the alpha-carbonic anhydrase family.

Ontologies

Keywords
Cellular component	Cytoplasm
Coding sequence diversity	Polymorphism
Disease	Disease mutation
Ligand	Metal-binding Zinc
Molecular function	Lyase
PTM	Acetylation
Technical term	3D-structure Direct protein sequencing
Gene Ontology (GO)
Cellular component	cytoplasm Inferred from direct assay. Source: UniProtKB
Molecular function	carbonate dehydratase activity Ref.18 Traceable author statement. Source: ProtInc zinc ion binding Ref.13 Inferred from direct assay. Source: UniProtKB
Complete GO annotation...

Sequence annotation (Features)

Feature key

Position(s)

Length

Description

Graphical view

Molecule processing

Initiator methionine

1

1

Removed

Chain

2 – 260

259

Carbonic anhydrase 2

Sites

Active site

64

1

Active site

67

1

Active site

127

1

Metal binding

94

1

Zinc; catalytic

Metal binding

96

1

Zinc; catalytic

Metal binding

119

1

Zinc; catalytic

Amino acid modifications

Modified residue

2

1

N-acetylserine

Natural variations

Natural variant

18

1

K → E in Jogjakarta.

Natural variant

92

1

Q → P in OPTB3; in Czechoslovakia.

Natural variant

94

1

H → Y in OPTB3; partial loss of activity.

Natural variant

107

1

H → Y in OPTB3; frequent mutation.

Natural variant

144

1

G → R in OPTB3; complete loss of activity.

Natural variant

236

1

P → H in Melbourne.

Natural variant

252

1

N → D: dbSNP rs2228063.

Experimental info

Sequence conflict

179 – 180

2

DP → AA in AAH11949. Ref.4

Secondary structure

1

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260

Helix Strand Turn

Details...

Turn

9 – 11

3

Turn

13 – 15

3

Helix

16 – 18

3

Helix

21 – 24

4

Beta strand

25 – 27

3

Turn

35 – 37

3

Beta strand

45 – 50

6

Beta strand

56 – 61

6

Beta strand

63 – 70

8

Beta strand

73 – 75

3

Beta strand

77 – 82

6

Beta strand

88 – 97

10

Beta strand

106 – 109

4

Beta strand

115 – 124

10

Helix

125 – 127

3

Helix

130 – 133

4

Beta strand

139 – 151

13

Helix

154 – 156

3

Helix

157 – 162

6

Helix

163 – 165

3

Beta strand

172 – 174

3

Helix

180 – 183

4

Beta strand

190 – 195

6

Beta strand

206 – 213

8

Beta strand

215 – 217

3

Helix

219 – 225

7

Beta strand

229 – 231

3

Beta strand

256 – 258

3

Sequences

	Sequence		Length	Mass (Da)
	P00918-1 [UniParc]. Last modified January 23, 2007. Version 2. Checksum: 2EC2BB7548F10558	FASTA	260	29,246
	10 20 30 40 50 60 MSHHWGYGKH NGPEHWHKDF PIAKGERQSP VDIDTHTAKY DPSLKPLSVS YDQATSLRIL 70 80 90 100 110 120 NNGHAFNVEF DDSQDKAVLK GGPLDGTYRL IQFHFHWGSL DGQGSEHTVD KKKYAAELHL 130 140 150 160 170 180 VHWNTKYGDF GKAVQQPDGL AVLGIFLKVG SAKPGLQKVV DVLDSIKTKG KSADFTNFDP 190 200 210 220 230 240 RGLLPESLDY WTYPGSLTTP PLLECVTWIV LKEPISVSSE QVLKFRKLNF NGEGEPEELM 250 260 VDNWRPAQPL KNRQIKASFK

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"Nucleotide sequence of human liver carbonic anhydrase II cDNA." Montgomery J.C., Venta P.J., Tashian R.E., Hewett-Emmett D. Nucleic Acids Res. 15:4687-4687(1987) [PubMed: 3108857] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA].
[2]	"Cloning, expression, and sequence homologies of cDNA for human carbonic anhydrase II." Murakami H., Marelich G.P., Grubb J.H., Kyle J.W., Sly W.S. Genomics 1:159-166(1987) [PubMed: 3121496] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA].
[3]	"Cloning of human full open reading frames in Gateway(TM) system entry vector (pDONR201)." Halleck A., Ebert L., Mkoundinya M., Schick M., Eisenstein S., Neubert P., Kstrang K., Schatten R., Shen B., Henze S., Mar W., Korn B., Zuo D., Hu Y., LaBaer J. Submitted (JUN-2004) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
[4]	"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]. Tissue: Ovary.
[5]	"Human carbonic anhydrases. XII. The complete primary structure of the C isozyme." Lin K.-T.D., Deutsch H.F. J. Biol. Chem. 249:2329-2337(1974) [PubMed: 4207120] [Abstract] Cited for: PROTEIN SEQUENCE OF 2-260.
[6]	"Primary structure of human carbonic anhydrase C." Henderson L.E., Henriksson D., Nyman P.O. J. Biol. Chem. 251:5457-5463(1976) [PubMed: 823150] [Abstract] Cited for: PROTEIN SEQUENCE OF 2-260.
[7]	"Comparison of the 5' regions of human and mouse carbonic anhydrase II genes and identification of possible regulatory elements." Venta P.J., Montgomery J.C., Hewett-Emmett D., Tashian R.E. Biochim. Biophys. Acta 826:195-201(1985) [PubMed: 3000449] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA] OF 1-77.
[8]	"Direct extracellular interaction between carbonic anhydrase IV and the human NBC1 sodium/bicarbonate co-transporter." Alvarez B.V., Loiselle F.B., Supuran C.T., Schwartz G.J., Casey J.R. Biochemistry 42:12321-12329(2003) [PubMed: 14567693] [Abstract] Cited for: INTERACTION WITH SLC4A4.
[9]	"Regulation of the human NBC3 Na+/HCO3- cotransporter by carbonic anhydrase II and PKA." Loiselle F.B., Morgan P.E., Alvarez B.V., Casey J.R. Am. J. Physiol. 286:C1423-C1433(2004) [PubMed: 14736710] [Abstract] Cited for: INTERACTION WITH SLC4A7.
[10]	"Molecular mechanism of kNBC1-carbonic anhydrase II interaction in proximal tubule cells." Pushkin A., Abuladze N., Gross E., Newman D., Tatishchev S., Lee I., Fedotoff O., Bondar G., Azimov R., Ngyuen M., Kurtz I. J. Physiol. (Lond.) 559:55-65(2004) [PubMed: 15218065] [Abstract] Cited for: INTERACTION WITH SLC4A4.
[11]	"Crystal structure of human carbonic anhydrase C." Liljas A., Kannan K.K., Bergsten P.-C., Waara I., Fridborg K., Strandberg B., Carlbom U., Jaerup L., Loevgren S., Petef M. Nature New Biol. 235:131-137(1972) [PubMed: 4621826] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.0 ANGSTROMS).
[12]	"Refined structure of human carbonic anhydrase II at 2.0-A resolution." Eriksson A.E., Jones T.A., Liljas A. Proteins 4:274-282(1988) [PubMed: 3151019] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.0 ANGSTROMS).
[13]	"Crystallographic studies of inhibitor binding sites in human carbonic anhydrase II: a pentacoordinated binding of the SCN-ion to the zinc at high pH." Eriksson A.E., Kylsten P.M., Jones T.A., Liljas A. Proteins 4:283-293(1988) [PubMed: 3151020] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.0 ANGSTROMS).
[14]	"Structures of murine carbonic anhydrase IV and human carbonic anhydrase II complexed with brinzolamide: molecular basis of isozyme-drug discrimination." Stams T., Chen Y., Boriack-Sjodin P.A., Hurt J.D., Liao J., May J.A., Dean T., Laipis P., Silverman D.N., Christianson D.W. Protein Sci. 7:556-563(1998) [PubMed: 9541386] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.25 ANGSTROMS).
[15]	"Structural influence of hydrophobic core residues on metal binding and specificity in carbonic anhydrase II." Cox J.D., Hunt J.A., Compher K.M., Fierke C.A., Christianson D.W. Biochemistry 39:13687-13694(2000) [PubMed: 11076507] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.0 ANGSTROMS).
[16]	"Chemical and enzymological characterization of an Indonesian variant of human erythrocyte carbonic anhydrase II, CAII Jogjakarta (17 Lys leads to Glu)." Jones G.L., Sofro A.S.M., Shaw D.C. Biochem. Genet. 20:979-1000(1982) [PubMed: 6817747] [Abstract] Cited for: VARIANT JOGJAKARTA GLU-18.
[17]	"A chemical and enzymological comparison of the common major human erythrocyte carbonic anhydrase II, its minor component, and a new genetic variant, CA II Melbourne (237 Pro leads to His)." Jones G.L., Shaw D.C. Hum. Genet. 63:392-399(1983) [PubMed: 6407977] [Abstract] Cited for: VARIANT MELBOURNE HIS-236.
[18]	"Carbonic anhydrase II deficiency syndrome in a Belgian family is caused by a point mutation at an invariant histidine residue (107 His-->Tyr): complete structure of the normal human CA II gene." Venta P.J., Welty R.J., Johnson T.M., Sly W.S., Tashian R.E. Am. J. Hum. Genet. 49:1082-1090(1991) [PubMed: 1928091] [Abstract] Cited for: VARIANT OPTB3 TYR-107.
[19]	"Molecular basis of human carbonic anhydrase II deficiency." Roth D.E., Venta P.J., Tashian R.E., Sly W.S. Proc. Natl. Acad. Sci. U.S.A. 89:1804-1808(1992) [PubMed: 1542674] [Abstract] Cited for: VARIANT OPTB3 TYR-107.
[20]	"A point mutation in exon 3 (His 107-->Tyr) in two unrelated Japanese patients with carbonic anhydrase II deficiency with central nervous system involvement." Soda H., Yukizane S., Yoshida I., Koga Y., Aramaki S., Kato H. Hum. Genet. 97:435-437(1996) [PubMed: 8834238] [Abstract] Cited for: VARIANT OPTB3 TYR-107.
[21]	"Seven novel mutations in carbonic anhydrase II deficiency syndrome identified by SSCP and direct sequencing analysis." Hu P.Y., Lim E.J., Ciccolella J., Strisciuglio P., Sly W.S. Hum. Mutat. 9:383-387(1997) [PubMed: 9143915] [Abstract] Cited for: VARIANT OPTB3 PRO-92.
[22]	"Carbonic anhydrase II deficiency syndrome (osteopetrosis with renal tubular acidosis and brain calcification): novel mutations in CA2 identified by direct sequencing expand the opportunity for genotype-phenotype correlation." Shah G.N., Bonapace G., Hu P.Y., Strisciuglio P., Sly W.S. Hum. Mutat. 24:272-272(2004) [PubMed: 15300855] [Abstract] Cited for: VARIANTS OPTB3 PRO-92; TYR-94; TYR-107 AND ARG-144, CHARACTERIZATION OF VARIANTS TYR-94 AND ARG-144.
+	Additional computationally mapped references.

Web resources

GeneReviews

Cross-references

Sequence databases

EMBLGenBankDDBJ

M77181 , M77176, M77177, M77178, M77179, M77180 Genomic DNA. Translation: AAA51909.1.
Y00339 mRNA. Translation: CAA68426.1.
X03251 Genomic DNA. Translation: CAA27012.1.
J03037 mRNA. Translation: AAA51908.1.
CR536526 mRNA. Translation: CAG38763.1.
CR541875 mRNA. Translation: CAG46673.1.
BC011949 mRNA. Translation: AAH11949.1.
M36532 mRNA. Translation: AAA51911.1.

PIR

CRHU2. A27175.

RefSeq

NP_000058.1.

UniGene

Hs.155097

3D structure databases

PDBMSD

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
12CA	X-ray	2.40	A	1-260	[»]
1A42	X-ray	2.25	A	1-260	[»]
1AM6	X-ray	2.00	A	1-260	[»]
1AVN	X-ray	2.00	A	1-260	[»]
1BCD	X-ray	1.90	A	1-260	[»]
1BIC	X-ray	1.90	A	1-260	[»]
1BN1	X-ray	2.10	A	1-260	[»]
1BN3	X-ray	2.20	A	1-260	[»]
1BN4	X-ray	2.10	A	1-260	[»]
1BNM	X-ray	2.60	A	1-260	[»]
1BNN	X-ray	2.30	A	1-260	[»]
1BNQ	X-ray	2.40	A	1-260	[»]
1BNT	X-ray	2.15	A	1-260	[»]
1BNU	X-ray	2.15	A	1-260	[»]
1BNV	X-ray	2.40	A	1-260	[»]
1BNW	X-ray	2.25	A	1-260	[»]
1BV3	X-ray	1.85	A	1-260	[»]
1CA2	X-ray	2.00	A	1-260	[»]
1CA3	X-ray	2.30	A	1-260	[»]
1CAH	X-ray	1.88	A	1-260	[»]
1CAI	X-ray	1.80	A	1-260	[»]
1CAJ	X-ray	1.90	A	1-260	[»]
1CAK	X-ray	1.90	A	1-260	[»]
1CAL	X-ray	2.20	A