P83689 (OCP_SPIMA) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names	Recommended name: Orange carotenoid-binding protein Short name=OCP Cleaved into the following chain: Red carotenoid-binding protein Short name=RCP
Organism	Spirulina maxima (Arthrospira maxima)
Taxonomic identifier	129910 [NCBI]
Taxonomic lineage	cellular organisms › Bacteria › Cyanobacteria › Oscillatoriophycideae › Oscillatoriales › Arthrospira

Protein attributes

Sequence length	317 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	Acts as a photo-protectant. Essential for inhibiting white and blue-green light non-photochemical quenching (NPQ). Binding carotenoids improves OCP's intrinsic photoprotectant activity by broadening its absorption spectrum and facilitating the dissipation of absorbed energy. Ref.4
Subunit structure	Homodimer. Ref.6
Subcellular location	Cellular thylakoid membrane. Note: Associated with the phycobilisome By similarity. UniProtKB P74102
Post-translational modification	Proteolytically cleaved into a red 16.7 kDa form named red carotenoid-binding protein (RCP) which lacks 15 residues from the N-terminus and approximately 150 residues from the C-terminus By similarity. Ref.2
Miscellaneous	Binds 1 carotenoid (3'-hydroxyechinenone) molecule and 1 chloride ion per subunit.
Biophysicochemical properties	Absorption: Abs(max)=494 nm Ref.2 Also shows other maxima at 465 nm and 275 nm. The red form (RCP) shows a broad peak at 500 nm. Ref.2

Ontologies

Keywords
Cellular component	Membrane Phycobilisome Thylakoid
Technical term	3D-structure Direct protein sequencing
Gene Ontology (GO)
Biological_process	light absorption Inferred from electronic annotation. Source: InterPro transport Inferred from electronic annotation. Source: InterPro
Cellular_component	phycobilisome Inferred from electronic annotation. Source: UniProtKB-KW
Molecular_function	chloride ion binding Inferred from electronic annotation. Source: InterPro
Complete GO annotation...

Sequence annotation (Features)

Feature key

Position(s)

Length

Description

Graphical view

Feature identifier

Molecule processing

Initiator methionine

1

1

Removed Ref.1

Chain

2 – 317

316

Orange carotenoid-binding protein Ref.1

PRO_0000282350

Chain

16 – ?

Red carotenoid-binding protein By similarity

PRO_0000282351

Regions

Region

37 – 44

8

Carotenoid-binding Ref.6

Region

107 – 114

8

Carotenoid-binding Ref.6

Region

151 – 158

8

Carotenoid-binding Ref.6

Region

203 – 207

5

Carotenoid-binding Ref.6

Region

247 – 252

6

Carotenoid-binding Ref.6

Region

275 – 280

6

Carotenoid-binding Ref.6

Sites

Binding site

53

1

Carotenoid Ref.6

Binding site

227

1

Carotenoid Ref.6

Binding site

277

1

Chloride Ref.6

Binding site

286

1

Carotenoid Ref.6

Binding site

290

1

Carotenoid Ref.6

Binding site

305

1

Carotenoid Ref.6

Secondary structure

1

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

317

Helix Strand Turn

Details...

Helix

5 – 8

4

Helix

20 – 28

9

Helix

33 – 50

18

Helix

58 – 73

16

Helix

76 – 88

13

Helix

93 – 99

7

Helix

103 – 118

16

Helix

133 – 144

12

Helix

147 – 159

13

Helix

184 – 186

3

Helix

198 – 208

11

Helix

212 – 216

5

Beta strand

219 – 226

8

Beta strand

233 – 235

3

Helix

236 – 246

11

Beta strand

251 – 261

11

Helix

263 – 265

3

Beta strand

267 – 276

10

Turn

278 – 280

3

Helix

281 – 283

3

Beta strand

286 – 294

9

Beta strand

300 – 310

11

Helix

311 – 315

5

Sequences

	Sequence		Length	Mass (Da)
	P83689 [UniParc]. Last modified December 15, 2003. Version 1. Checksum: D72A95D89DEF52EA	FASTA	317	35,348
	10 20 30 40 50 60 MPFTIDTARS IFPETLAADV VPATIARFKQ LSAEDQLALI WFAYLEMGKT ITIAAPGAAN 70 80 90 100 110 120 MQFAENTLQE IRQMTPLQQT QAMCDLANRT DTPICRTYAS WSPNIKLGFW YELGRFMDQG 130 140 150 160 170 180 LVAPIPEGYK LSANANAILV TIQGIDPGQQ ITVLRNCVVD MGFDTSKLGS YQRVAEPVVP 190 200 210 220 230 240 PQEMSQRTKV QIEGVTNSTV LQYMDNLNAN DFDNLISLFA EDGALQPPFQ KPIVGKENTL 250 260 270 280 290 300 RFFREECQNL KLIPERGVSE PTEDGYTQIK VTGKVQTPWF GGNVGMNIAW RFLLNPENKV 310 FFVAIDLLAS PKELLNL

References

[1]	"The orange carotenoid protein of Synechocystis PCC 6803." Wu Y.P., Krogmann D.W. Biochim. Biophys. Acta 1322:1-7(1997) [PubMed] [Europe PMC] [Abstract] Cited for: PROTEIN SEQUENCE OF 2-29.
[2]	"A carotenoid-protein from cyanobacteria." Holt T.K., Krogmann D.W. Biochim. Biophys. Acta 637:408-414(1981) Cited for: BIOPHYSICOCHEMICAL PROPERTIES, IDENTIFICATION OF CAROTENOID, PROTEOLYTIC CLEAVAGE.
[3]	"Water-soluble carotenoid proteins of cyanobacteria." Kerfeld C.A. Arch. Biochem. Biophys. 430:2-9(2004) [PubMed] [Europe PMC] [Abstract] Cited for: REVIEW ON FUNCTION; BIOPHYSICOCHEMICAL PROPERTIES; SUBUNIT; SUBCELLULAR LOCATION AND PROTEOLYTIC CLEAVAGE.
[4]	"Spectroscopic properties of the carotenoid 3'-hydroxyechinenone in the orange carotenoid protein from the cyanobacterium Arthrospira maxima." Polivka T., Kerfeld C.A., Pascher T., Sundstroem V. Biochemistry 44:3994-4003(2005) [PubMed] [Europe PMC] [Abstract] Cited for: FUNCTION.
[5]	"Crystals of the carotenoid protein from Arthrospira maxima containing uniformly oriented pigment molecules." Kerfeld C.A., Wu Y.P., Chan C., Krogmann D.W., Yeates T.O. Acta Crystallogr. D 53:720-723(1997) [PubMed] [Europe PMC] [Abstract] Cited for: CRYSTALLIZATION.
[6]	"The crystal structure of a cyanobacterial water-soluble carotenoid binding protein." Kerfeld C.A., Sawaya M.R., Brahmandam V., Cascio D., Ho K.K., Trevithick-Sutton C.C., Krogmann D.W., Yeates T.O. Structure 11:55-65(2003) [PubMed] [Europe PMC] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.1 ANGSTROMS) IN COMPLEX WITH CAROTENOID, SUBUNIT.

Cross-references

3D structure databases

PDBe
RCSB PDB
PDBj

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
1M98	X-ray	2.10	A/B	1-317	[»]

ProteinModelPortal

P83689.

SMR

P83689. Positions 2-317.

ModBase

Search...

Protocols and materials databases

StructuralBiologyKnowledgebase

Search...

Family and domain databases

Gene3D

1.10.2090.10. 1 hit.

InterPro

IPR002075. NTF2.
IPR015233. Orange_carotenoid-bd_N.
[Graphical view]

Pfam

PF09150. Carot_N. 1 hit.
PF02136. NTF2. 1 hit.
[Graphical view]

SUPFAM

SSF81930. Orange_carotenoid-bd_N. 1 hit.

ProtoNet

Search...

Other

EvolutionaryTrace

P83689.

Entry information

Entry name

OCP_SPIMA

Accession

Primary (citable) accession number: P83689

Entry history

Integrated into UniProtKB/Swiss-Prot:	April 3, 2007
Last sequence update:	December 15, 2003
Last modified:	May 1, 2013
This is version 34 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Prokaryotic Protein Annotation Program