The Lipocalin Protein Family: Protein Sequence, Structure and Relationship to the Calycin Superfamily
Lola Ganfornina, Diego Sanchez, Lesley H Greene and Darren R. Flower
Lipocalins are remarkable in their diversity, as manifest at the levels of protein sequence
and protein function. At the level of 3-dimensional structure, however, they are very similar. The lipocalins are also part of a larger protein superfamily: the calycins, which also includes the fatty acid binding proteins, avidins, a group of metalloproteinase inhibitors, and triabin. The superfamily is characterised by a similar structure (a repeated +1 topology b-barrel) and by the conservation of a remarkable structural signature. In this review, both of these aspects are explored.