Reviewed, UniProtKB/Swiss-Prot P02754 (LACB_BOVIN)

Names and origin

Protein names

Recommended name:
    Beta-lactoglobulin
      Short name=Beta-LG
Alternative name(s):
    Allergen=Bos d 5

Gene names

Name:

LGB

Organism

Bos taurus (Bovine)

Taxonomic identifier

9913 [NCBI]

Taxonomic lineage

Eukaryota › Metazoa › Chordata › Craniata › Vertebrata › Euteleostomi › Mammalia › Eutheria › Laurasiatheria › Cetartiodactyla › Ruminantia › Pecora › Bovidae › Bovinae › Bos

Protein attributes

Sequence length	178 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	Primary component of whey, it binds retinol and is probably involved in the transport of that molecule.
Subunit structure	Under physiological conditions beta-lactoglobulin exists as an equilibrium mixture of monomeric and dimeric forms.
Subcellular location	Secreted.
Tissue specificity	Synthesized in mammary glound and secreted in milk.
Post-translational modification	Alternate disulfide bonds occur in equal amounts in all variants examined.
Allergenic properties	Causes an allergic reaction in human. Is one of the causes of cow's milk allergy.
Miscellaneous	The B variant sequence is shown.
Sequence similarities	Belongs to the calycin superfamily. Lipocalin family.

Ontologies

Keywords
Biological process	Transport
Cellular component	Secreted
Coding sequence diversity	Polymorphism
Disease	Allergen
Domain	Signal
Ligand	Retinol-binding
Molecular function	Milk protein
PTM	Disulfide bond
Technical term	3D-structure Direct protein sequencing
Gene Ontology (GO)
Biological process	transport Inferred from electronic annotation. Source: UniProtKB-KW
Cellular component	extracellular region Inferred from electronic annotation. Source: UniProtKB-SubCell
Molecular function	retinol binding Inferred from electronic annotation. Source: UniProtKB-KW transporter activity Inferred from electronic annotation. Source: InterPro
Complete GO annotation...

Sequence annotation (Features)

Feature key

Position(s)

Length

Description

Graphical view

Feature identifier

Molecule processing

Signal peptide

1 – 16

16

Ref.6 Ref.8

Chain

17 – 178

162

Beta-lactoglobulin

PRO_0000017903

Amino acid modifications

Disulfide bond

82 ↔ 176

Ref.13 Ref.19

Disulfide bond

122 ↔ 137

Alternate Ref.13

Disulfide bond

122 ↔ 135

Ref.13 Ref.19

Natural variations

Natural variant

61

1

E → Q in variant D. Ref.10

Natural variant

72

1

I → L in variant W. Ref.8

Natural variant

75

1

Q → H in variant C; found only in the Jersey breed. Ref.14

Natural variant

80

1

G → D in variant A. Ref.6 Ref.1 Ref.9

Natural variant

134

1

A → V in variant A. Ref.6 Ref.1 Ref.9 Ref.12

Experimental info

Sequence conflict

121

1

F → V in CAA32835. Ref.1

Sequence conflict

136

1

Q → E Ref.12

Secondary structure

1

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178

Helix Strand Turn

Details...

Helix

19 – 21

3

Helix

28 – 31

4

Beta strand

36 – 44

9

Helix

45 – 48

4

Beta strand

58 – 64

7

Beta strand

70 – 78

9

Beta strand

81 – 91

11

Beta strand

97 – 100

4

Beta strand

102 – 104

3

Beta strand

106 – 113

8

Beta strand

115 – 130

16

Beta strand

132 – 141

10

Helix

147 – 155

9

Helix

156 – 158

3

Beta strand

162 – 166

5

Helix

169 – 172

4

Sequences

	Sequence		Length	Mass (Da)
	P02754-1 [UniParc]. Last modified August 1, 1991. Version 3. Checksum: 225F10A78C63A6B2	FASTA	178	19,883
	10 20 30 40 50 60 MKCLLLALAL TCGAQALIVT QTMKGLDIQK VAGTWYSLAM AASDISLLDA QSAPLRVYVE 70 80 90 100 110 120 ELKPTPEGDL EILLQKWENG ECAQKKIIAE KTKIPAVFKI DALNENKVLV LDTDYKKYLL 130 140 150 160 170 FCMENSAEPE QSLACQCLVR TPEVDDEALE KFDKALKALP MHIRLSFNPT QLEEQCHI

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"Complete sequence of the bovine beta-lactoglobulin cDNA." Alexander L.J., Hayes G., Pearse M.J., Beattie C.W., Stewart A.F., Willis I.M., McKinlay A.G. Nucleic Acids Res. 17:6739-6739(1989) [PubMed: 2701948] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA], VARIANTS ASP-80 AND VAL-134. Tissue: Mammary gland.
[2]	"Bovine beta-lactoglobulin: cloning and expression in transgenic mice." Hyttinen J.M., Korhonen V.P., Myohanen S., Janne J. Submitted (FEB-1995) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA]. Tissue: Sperm.
[3]	"Aberrant low expression level of bovine beta-lactoglobulin B." Braunschweig M.H. Submitted (APR-2006) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[4]	NIH - Mammalian Gene Collection (MGC) project Submitted (OCT-2005) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA]. Strain: Crossbred X Angus. Tissue: Liver.
[5]	"Cloning and partial nucleotide sequence of the genomic bovine beta-lactoglobulin gene." Silva M.C., Wong D.W.S., Batt C.A. Nucleic Acids Res. 18:3051-3051(1990) [PubMed: 2349102] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA] OF 1-20. Tissue: Pituitary.
[6]	"The sequence of beta-lactoglobulin." Braunitzer G., Chen R., Schrank B., Stangl A. Hoppe-Seyler's Z. Physiol. Chem. 354:867-878(1973) [PubMed: 4611888] [Abstract] Cited for: PROTEIN SEQUENCE OF 17-178, VARIANTS ASP-80 AND VAL-134.
[7]	"The amino acid sequence of goat beta-lactoglobulin." Preaux G., Braunitzer G., Schrank B., Stangl A. Hoppe-Seyler's Z. Physiol. Chem. 360:1595-1604(1979) [PubMed: 511095] [Abstract] Cited for: SEQUENCE REVISION TO 100; 103; 171 AND 172.
[8]	"Genetic variants of bovine beta-lactoglobulin. A novel wild-type beta-lactoglobulin W and its primary sequence." Godovac-Zimmermann J., Krause I., Buchberger J., Weiss G., Klostermeyer H. Biol. Chem. Hoppe-Seyler 371:255-260(1990) [PubMed: 2340107] [Abstract] Cited for: PROTEIN SEQUENCE OF 17-178, VARIANT LEU-72. Strain: Murnau-Werdenfelser.
[9]	"Cloning and nucleotide sequence of the bovine beta-lactoglobulin gene." Jamieson A.C., Vandeyar M.A., Kang Y.C., Kinsella J.E., Batt C.A. Gene 61:85-90(1987) [PubMed: 3443305] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA] OF 28-178, VARIANTS ASP-80 AND VAL-134.
[10]	"Localization of the Glu-Gln substitution differentiating B and D genetic variants in the peptide chain of bovine beta lactoglobulin." Brignon G., Ribadeau-Dumas B. FEBS Lett. 33:73-76(1973) [PubMed: 4737332] [Abstract] Cited for: PROTEIN SEQUENCE OF 59-73, VARIANT GLN-61.
[11]	"Molecular cloning of bovine beta-lactoglobulin cDNA." Ivanov V.N., Judinkova E.S., Gorodetsky S.I. Biol. Chem. Hoppe-Seyler 369:425-429(1988) [PubMed: 3202951] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] OF 122-178.
[12]	"Construction and identification by partial nucleotide sequence analysis of bovine casein and beta-lactoglobulin cDNA clones." Willis I.M., Stewart A.F., Caputo A., Thompson A.R., McKinlay A.G. DNA 1:375-386(1982) [PubMed: 6897774] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] OF 125-138, VARIANT VAL-134.
[13]	"Location of sulfhydryl and disulfide groups in bovine beta-lactoglobulins and effects of urea." McKenzie H.A., Ralston G.B., Shaw D.C. Biochemistry 11:4539-4547(1972) [PubMed: 4569282] [Abstract] Cited for: DISULFIDE BONDS.
[14]	Shaw D.C. Submitted (JAN-1973) to the PIR data bank Cited for: VARIANT HIS-75.
[15]	"Three-dimensional structure and active site of three hydrophobic molecule-binding proteins with significant amino acid sequence similarity." Monaco H.L., Zanotti G. Biopolymers 32:457-465(1992) [PubMed: 1623143] [Abstract] Cited for: COMPARISON OF X-RAY STRUCTURES.
[16]	"Bovine beta-lactoglobulin at 1.8-A resolution -- still an enigmatic lipocalin." Brownlow S., Morais-Cabral J.H., Cooper R., Flower D.R., Yewdall S.J., Polikarpov I., North A.C.T., Sawyer L. Structure 5:481-495(1997) [PubMed: 9115437] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (1.8 ANGSTROMS).
[17]	"Structural basis of the tanford transition of bovine beta-lactoglobulin." Qin B.Y., Bewley M.C., Creamer L.K., Baker H.M., Baker E.N., Jameson G.B. Biochemistry 37:14014-14023(1998) [PubMed: 9760236] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.22 ANGSTROMS).
[18]	"Partially folded structure of monomeric bovine beta-lactoglobulin." Molinari H., Ragona L., Varani L., Musco G., Consonni R., Zetta L., Monaco H.L. FEBS Lett. 381:237-243(1996) [PubMed: 8601463] [Abstract] Cited for: STRUCTURE BY NMR.
[19]	"Solution structure and dynamics of bovine beta-lactoglobulin A." Kuwata K., Hoshino M., Forge V., Era S., Batt C.A., Goto Y. Protein Sci. 8:2541-2545(1999) [PubMed: 10595563] [Abstract] Cited for: STRUCTURE BY NMR OF VARIANT A.
+	Additional computationally mapped references.

Cross-references

Sequence databases

EMBLGenBankDDBJ

X14712 mRNA. Translation: CAA32835.1.
Z48305 Genomic DNA. Translation: CAA88303.1.
DQ489319 Genomic DNA. Translation: ABF48380.1.
BC108213 mRNA. Translation: AAI08214.1.
X52581 Genomic DNA. Translation: CAA36812.1.
M19088 Genomic DNA. Translation: AAA30411.1.
M27732 mRNA. Translation: AAA30412.1.
K01086 mRNA. Translation: AAA30413.1.

IPI

IPI00699698.

PIR

LGBO. S10179.

RefSeq

NP_776354.2.

UniGene

Bt.385

3D structure databases

PDBPDBe

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
1B0O	X-ray	2.50	A	17-178	[»]
1B8E	X-ray	1.95	A	17-178	[»]
1BEB	X-ray	1.80	A/B	17-178	[»]
1BSO	X-ray	2.23	A	17-178	[»]
1BSQ	X-ray	2.22	A	17-178	[»]
1BSY	X-ray	2.24	A	17-178	[»]
1CJ5	NMR	-	A	19-178	[»]
1DV9	NMR	-	A	19-178	[»]
1GX8	X-ray	2.40	A	17-178	[»]
1GX9	X-ray	2.34	A	17-178	[»]
1GXA	X-ray	2.35	A	17-178	[»]
1QG5	X-ray	2.00	A	17-178	[»]
1UZ2	X-ray	1.95	X	17-178	[»]
1YUP	X-ray	2.10	D	18-176	[»]
2AKQ	X-ray	3.00	A/B/C/D	17-178	[»]
2BLG	X-ray	2.46	A	17-178	[»]
2GJ5	X-ray	2.40	A	17-178	[»]
2Q2M	X-ray	2.10	A	17-178	[»]
2Q2P	X-ray	2.96	A	17-178	[»]
2Q39	X-ray	2.50	A/B	17-178	[»]
2R56	X-ray	2.80	A/B	17-178	[»]
3BLG	X-ray	2.56	A	17-178	[»]

DisProt

DP00193.

ModBase

Search...

Protein-protein interaction databases

STRING

P02754.

PTM databases

GlycoSuiteDB

P02754.

Genome annotation databases

Ensembl

ENSBTAT00000019538; ENSBTAP00000019538; ENSBTAG00000014678; Bos taurus. [Genome view]

GeneID

280838.

KEGG

bta:280838.

Organism-specific databases

CTD

280838.

Phylogenomic databases

HOVERGEN

P02754.

OMA

AMATNNI.

Family and domain databases

InterPro

IPR002447. Blactoglobulin.
IPR012674. Calycin.
IPR002345. Lipocalin.
IPR000566. Lipocln_cytFABP.
[Graphical view]

Gene3D

G3DSA:2.40.128.20. Calycin. 1 hit.

PANTHER

PTHR11430:SF18. Blactoglobulin. 1 hit.

Pfam

PF00061. Lipocalin. 1 hit.
[Graphical view]

PRINTS

PR01172. BLCTOGLOBULN.
PR00179. LIPOCALIN.

PROSITE

PS00213. LIPOCALIN. 1 hit.
[Graphical view]

ProtoNet

Search...

Entry information

Entry name

LACB_BOVIN

Accession

Primary (citable) accession number: P02754
Secondary accession number(s): Q32P89

Entry history

Integrated into UniProtKB/Swiss-Prot:	July 21, 1986
Last sequence update:	August 1, 1991
Last modified:	November 3, 2009
This is version 97 of the entry and version 3 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

HPI (Human Proteome Initiative)