InterPro : IPR002447

Name  Beta-lactoglobulin Short Name  Blactoglobulin
Type  Family Description  The lipocalins are a diverse, interesting, yet poorly understood family of proteins composed, in the main, of extracellular ligand-binding proteinsdisplaying high specificity for small hydrophobic molecules [, ]. Functionsof these proteins include transport of nutrients, control of cell regulation, pheromone transport, cryptic colouration and the enzymatic synthesisof prostaglandins.The crystal structures of several lipocalins have been solved and show a novel 8-stranded anti-parallel beta-barrel fold well conserved within thefamily. Sequence similarity within the family is at a much lower level andwould seem to be restricted to conserved disulphides and 3 motifs, whichform a juxtaposed cluster that may act as a common cell surface receptorsite []. By contrast, at the more variable end of the fold are found an internal ligand binding site and a putative surface for the formation of macromolecular complexes []. The anti-parallel beta-barrel fold is alsoexploited by the fatty acid-binding proteins (which function similarly bybinding small hydrophobic molecules), by avidin and the closely relatedmetalloprotease inhibitors, and by triabin. Similarity at the sequence level, however, is less obvious, being confined to a single short N-terminal motif.The lipocalin family can be subdivided into kernal and outlier sets. Thekernal lipocalins form the largest self consistent group, comprising the subfamily of beta-lactoglobulins. The outlier lipocalins form several smaller distinct subgroups: the OBPs, the von Ebner's gland proteins, alpha-1-acid glycoproteins, tick histamine binding proteins and the nitrophorins.Beta-lactoglobulin (Blg) is the major protein component of milk from a wide range of species but not human. Glycodelin or PP14 protein is the human equivalent of Blg and is secreted into the endometrium. Blg binds a wide variety of hydrophobic ligands but its function remains unknown. The crystalstructure of Blg has been solved [], confirming membership of the lipocalinprotein family.

Sequence Features

GO Displayer


InterPro protein domain ID --> Contigs



0 Child Features

1 Contains

Id Name Short Name Type
IPR022272 Lipocalin family conserved site Lipocalin_CS Conserved_site

0 Found In

1 Parent Features

Id Name Short Name Type
IPR002345 Lipocalin Lipocalin Family

4 Publications

First Author Title Year Journal Volume Pages
Flower DR Multiple molecular recognition properties of the lipocalin protein family. 1995 J Mol Recognit 8 185-95
Pervaiz S Homology of beta-lactoglobulin, serum retinol-binding protein, and protein HC. 1985 Science 228 335-7
Flower DR The lipocalin protein family: structure and function. 1996 Biochem J 318 ( Pt 1) 1-14
Brownlow S Bovine beta-lactoglobulin at 1.8 A resolution--still an enigmatic lipocalin. 1997 Structure 5 481-95

To cite PlanMine, please refer to the following publication:

Rozanski, A., Moon, H., Brandl, H., Martín-Durán, J. M., Grohme, M., Hüttner, K., Bartscherer, K., Henry, I., & Rink, J. C.
PlanMine 3.0—improvements to a mineable resource of flatworm biology and biodiversity
Nucleic Acids Research, gky1070. doi:10.1093/nar/gky1070 (2018)