Bilin-binding protein

Phytochromes are a family of bilin binding proteins that function as photoreceptors, regulating many physiologic processes... 

Pieris brassicae bilin-binding protein p-BBP 2 Huber et al. (1987a)... 

Manduca sexta bilin-binding protein m-BBP 2.6 Holden et al. (1987)... 

Most of these proteins are also responsible for the inter and intracellular transport of the hydrophobic ligands, otherwise insoluble in a polar environment. Retinol binding protein [5], bilin binding protein [7], insecticyanin [2] and P-lactoglobulin [5,... 

Lipocalins are typical secretory proteins containing disulfide bonds. Human RBP possesses the maximal number of three disulfide cross-links that was observed so far. One of them joins the carboxy-terminal end of the polypeptide chain to the -barrel (Cys7°-Cys 7 ). Another one fixes the amino-terminal segment of the protein to the carboxy-terminal end of the a-helix (Cys" -Cys ). The third disulfide bond (Cys °-Cys ) links the two neighboring strands G and H just underneath loop 4 at the open end of the /1-barrel (cf. Fig. 8.2). The latter two disulfide bridges are characteristic for RBP. Although a Cys residue close to the amino-terminus is also found in several other lipocalins, it usually forms a disulfide bond with a Cys residue in strand G of the -barrel, as in the bilin-binding protein (BBP), which carries two disulfide bonds [31, 32]. 

Bilin binding protein FAST TV 132.7 121.9 63.9 P2A2J 3.5 Huber etal (1987)... 

Band 3 protein, human blood Barstar, B. amyloliquefaciens Basement membrane protein, mouse Bence Jones protein (Tod) Bilin-binding protein, P. brassicae... 

Protein - max A Quarternary structure Bilin content per subunit Bilin binding positions Number of residues % Homology between ap-subunits Refs. 

Fig. 8.1 Three types of scaffolds, with a convex, flat, and concave interface, respectively. (Left) Camel VhH domain, here presenting its extended CDR-3 loop towards the active site of an enzyme (PDB entry 1 MEL). (Middle) Protein A with its interface made of two a-he-lices directed against an Ig constant domain (PDB entry IBDD). (Right) Bilin-binding pro-...

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