Structure and characterization of a novel chicken biotin-binding protein A (BBP-A)
Open access
Datum
2007-03-07Typ
- Journal Article
ETH Bibliographie
yes
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Abstract
Background
The chicken genome contains a BBP-A gene showing similar characteristics to avidin family genes. In a previous study we reported that the BBP-A gene may encode a biotin-binding protein due to the high sequence similarity with chicken avidin, especially at regions encoding residues known to be located at the ligand-binding site of avidin.
Results
Here, we expand the repertoire of known macromolecular biotin binders by reporting a novel biotin-binding protein A (BBP-A) from chicken. The BBP-A recombinant protein was expressed using two different expression systems and purified with affinity chromatography, biochemically characterized and two X-ray structures were solved – in complex with D-biotin (BTN) and in complex with D-biotin D-sulfoxide (BSO). The BBP-A protein binds free biotin with high, "streptavidin-like" affinity (Kd ~ 10-13 M), which is about 50 times lower than that of chicken avidin. Surprisingly, the affinity of BBP-A for BSO is even higher than the affinity for BTN. Furthermore, the solved structures of the BBP-A – BTN and BBP-A – BSO complexes, which share the fold with the members of the avidin and lipocalin protein families, are extremely similar to each other.
Conclusion
BBP-A is an avidin-like protein having a β-barrel fold and high affinity towards BTN. However, BBP-A differs from the other known members of the avidin protein family in thermal stability and immunological properties. BBP-A also has a unique ligand-binding property, the ability to bind BTN and BSO at comparable affinities. BBP-A may have use as a novel material in, e.g. modern bio(nano)technological applications. Mehr anzeigen
Persistenter Link
https://doi.org/10.3929/ethz-b-000067975Publikationsstatus
publishedExterne Links
Zeitschrift / Serie
BMC Structural BiologyBand
Seiten / Artikelnummer
Verlag
BioMed CentralThema
Protein Data Bank; Dissociation Rate; Solvent Accessible Surface Area; Mutation A74S; Subunit InterfaceETH Bibliographie
yes
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