Fatty acid-binding proteins structure

Bakowies, D. Van Cunsteren,W.F. Simulations of apo and holo-fatty acid binding protein. Structure and dynamics of protein, ligand and internal water. J. Mol. Biol. 2002, 315, 713-736. 

There is a second family of small lipid-binding proteins, the P2 family, which include among others cellular retinol- and fatty acid-binding proteins as well as a protein, P2, from myelin in the peripheral nervous system. However, members of this second family have ten antiparallel p strands in their barrels compared with the eight strands found in the barrels of the RBP superfamily. Members of the P2 family show no amino acid sequence homology to members of the RBP superfamily. Nevertheless, their three-dimensional structures have similar architecture and topology, being up-and-down P barrels. 

Actual and predicted structures of three domains of intestinal fatty acid binding protein... 

The remaining major classes of water-soluble lipid transporter proteins (other than the polyproteins of nematodes see below) come from plants and helminths. Plants possess very small (approximately 9 kDa) helix-rich, fatty-acid-binding proteins, the structures of some of which are known (Lerche and Poulsen, 1998). A recently described class comes from cestodes these are also very small (approximately 8 kDa), presumably intracellular, and helix-rich, and bind anthelmintic drugs in addition to fatty acids (Janssen and Barrett, 1995 Barrett et al., 1997). The only helix-rich small (approximately 14 kDa) lipid transporter from vertebrates is the acetyl-CoA-binding protein (Kragelund et al., 1993). 

Kennedy, M.W., Scott, J.C., Lo, S.J., Beauchamp, J. and McManus, D.P. (2000) The Sj-FABPc fatty acid binding protein of the human blood fluke Schistosoma japonicum structural and functional characterisation and unusual solvent exposure of a portal-proximal tryptophan. BiochemicalJournal 349, 377-384. 

P2 protein. PNS myelin contains a positively charged protein different from MBP that is referred to as P2 (Mr — 15,000). It is unrelated in sequence to MBP and is a member of a family of cytoplasmic fatty acid binding proteins (FABP) that are present in a variety of cell types [25]. The amount of P2 protein is variable among species, accounting for about 15% of total protein in bovine PNS myelin, 5% in humans and less than 1% in rodents. P2 protein is generally considered a PNS myelin protein but it is expressed in small amounts in CNS myelin sheaths of some species. P2 is an antigen for experimental allergic neuritis, the PNS counterpart of EAE (see Chs 36 and 38). P2 appears to be present in the major dense line of myelin sheaths, where it may play a structural role similar to MBP... 

Ruse M, Broome AM, Eckert RL. 2003. S100A7 (psoriasin) interacts with epidermal fatty acid binding protein and localizes in focal adhesion-like structures in cultured keratinocytes. J Invest Dermatol 121(1) 132—141. 

Zimmerman, A. W. and Veerkamp, J. H., New insights into the structure and function of fatty acid-binding proteins. Cell Mol Life Sci, 2002, 59, 1096-1116. 

Veerkamp, I. H., et al., Structural and functional features of different types of cytoplasmic fatty acid-binding proteins. Biochim Biophys Acta, 1991,1081, 1-24. 

Bass NM (1988) The cellular fatty acid binding proteins aspects of structure, regulation, and function. Int Rev Cytol 111 143-84... 

Veerkamp, J.H., and R.G.H.J. Maatman (1995). Cytoplasmic fatty acid binding proteins their structure and genes. Prog. Lipid Res. 34 17-52. Viru, A. (1994). Molecular cellular mechanisms of training effects. J. Sports Med. Phys. Fitness 34 309-322. 

In schematic diagrams, P strands are usually depicted by broad arrows pointing in the direction of the carboxyl-terminal end to indicate the type of P sheet formed—parallel or antiparallel. More structurally diverse than a helices, P sheets can be relatively flat but most adopt a somewhat twisted shape (Figure 3.40). The P sheet is an important structural element in many proteins. For example, fatty acid-binding proteins, important for lipid metabolism, are built almost entirely from P sheets (Figure 3.41). 

Figure 3.41. A Protein Rich in p Sheets. The structure of a fatty acid-binding protein. 

A fatty acid binding protein has been crystallized, but x-ray analysis did not show the localization of the bound oligomethylene chains, nor was the protein structure changed significantly upon adsorption and desorption of palmitic acid (Miiller-Fahmow, 1991). 

Muller-Fahmow, A., Egner, U., Jones, A., Riidel, H., Spener, R, Saenger, W. (1991). Three-dimensional structure of fatty acid binding protein from bovine heart, Eur. J. Biochem. 199 271. 

Kimura H, Odani S, Nishi S, et al. 1991a. Primary structure and cellular distribution of two fatty acid-binding proteins in adult rat kidneys. J Biol Chem 266 5963-5972. 

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