Lipocalin Blc is a potential heme-binding protein

FEBS Letters

article

Nina G. Bozhanova¹  M. Wade Calcutt²  William N. Beavers³  Benjamin P. Brown¹  Eric P. Skaar³  Jens Meiler¹ 

[1] Department of Chemistry, Center for Structural Biology, Vanderbilt University;Mass Spectrometry Research Center, Department of Biochemistry, Vanderbilt University School of Medicine;Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center;Institute for Drug Discovery, Medical School, Leipzig University

关键词: Blc;    crystal structure;    hematoporphyrin;    heme-binding protein;    lipocalins;   

DOI  :  10.1002/1873-3468.14001

来源: John Wiley & Sons Ltd.

【 摘 要 】

Lipocalins are a superfamily of functionally diverse proteins defined by a well-conserved tertiary structure despite variation in sequence. Lipocalins bind and transport small hydrophobic molecules in organisms of all kingdoms. However, there is still uncertainty regarding the function of some members of the family, including bacterial lipocalin Blc from Escherichia coli . Here, we present evidence that lipocalin Blc may be involved in heme binding, trans-periplasmic transport, or heme storage. This conclusion is supported by a cocrystal structure, mass-spectrometric data, absorption titration, and in silico analysis. Binding of heme is observed at low micromolar range with one-to-one ligand-to-protein stoichiometry. However, the absence of classical coordination to the iron atom leaves the possibility that the primary ligand of Blc is another tetrapyrrole.

【 授权许可】

Unknown