Open AccessCrystallization and preliminary X‐ray crystallographic analysis of a Mycobacterium tuberculosis ferritin homolog, BfrB
Author(s) -
McMath L. M.,
Habel J. E.,
Sankaran B.,
Yu M.,
Hung L.W.,
Goulding C. W.
Publication year - 2010
Publication title -
acta crystallographica section f
Language(s) - English
Resource type - Journals
ISSN - 1744-3091
DOI - 10.1107/s1744309110042958
Subject(s) - crystallization , ferritin , x ray , crystallography , tuberculosis , x ray crystallography , chemistry , materials science , physics , medicine , biochemistry , pathology , diffraction , organic chemistry , optics
Mycobacterium tuberculosis (Mtb) is the causative agent of the deadly disease tuberculosis. Iron acquisition, regulation and storage are critical for the survival of this pathogen within a host. Thus, understanding the mechanisms of iron metabolism in Mtb will shed light on its pathogenic nature, as iron is important for infection. Ferritins are a superfamily of protein nanocages that function in both iron detoxification and storage, and Mtb contains both a predicted ferritin and a bacterioferritin. Here, the cloning, expression, purification, crystallization and preliminary X‐ray diffraction analysis of the ferritin homolog (Mtb BfrB, Rv3841) is reported. An Mtb BfrB crystal grown at pH 6.5 using the hanging‐drop vapor‐diffusion technique diffracted to 2.50 Å resolution and belonged to space group C 2, with unit‐cell parameters a = 226.2, b = 226.8, c = 113.7 Å, β = 94.7° and with 24 subunits per asymmetric unit. Furthermore, modeling the crystal structure of a homologous ferritin into a low‐resolution small‐angle X‐ray scattering (SAXS) electron‐density envelope is consistent with the presence of 24 subunits in the BfrB protein cage quaternary structure.