creators_name: Suhail Alam, Md
creators_name: Agrawal, Pushpa
type: article
datestamp: 2011-12-08 19:38:22
lastmod: 2011-12-08 19:38:22
metadata_visibility: show
title: Matrix-assisted refolding and redox properties of WhiB3/Rv3416 of Mycobacterium tuberculosis H37Rv.
ispublished: pub
subjects: QH301
full_text_status: restricted
note: copyright of this article belongs to Elsevier Science
abstract: Redox stress is one of the major challenges faced by Mycobacterium tuberculosis during early infection and latency. The mechanism of sensing and adaptation to altered redox conditions is poorly understood. whiB family of Mtb is emerging as an important class of stress responsive genes. WhiB3/Rv3416 has been shown to be important for pathogenesis in animal model and was recently shown to co-ordinate a Fe-S cluster. Here, we report a simple, rapid and efficient matrix-assisted refolding method and important redox properties of WhiB3. Similar to other WhiB proteins, WhiB3 also has four conserved cysteine residues, where two of them are present in a CXXC motif. The Fe-S cluster of WhiB3 remained bound in the presence of strong protein denaturant. Upon cluster removal due to oxidation, the four cysteine residues which are ligands of Fe-S cluster, formed two intra-molecular disulfide bridges where one of them is possibly between the cysteines of CXXC motif, an important feature of several thiol-disulfide oxido-reductases. Far-UV CD spectroscopy revealed the presence of both alpha-helices and beta-strands in apo WhiB3. The secondary structural elements of apo WhiB3 were found resistant for thermal denaturation. The results demonstrated that apo WhiB3 functions as a protein disulfide reductase similar to thioredoxins. The importance of WhiB3 in redox sensing and its possible role in mycobacterial physiology has been discussed.
date: 2008-09
date_type: published
publication: Protein expression and purification
volume: 61
number: 1
publisher: Elsevier Science
pagerange: 83-91
refereed: TRUE
issn: 1096-0279
official_url: http://www.sciencedirect.com/science/article/pii/S1046592808001198
related_url_url: http://www.sciencedirect.com/science/article/pii/S1046592808001198
related_url_type: pub
citation:   Suhail Alam, Md and Agrawal, Pushpa  (2008) Matrix-assisted refolding and redox properties of WhiB3/Rv3416 of Mycobacterium tuberculosis H37Rv.  Protein expression and purification, 61 (1).  pp. 83-91.  ISSN 1096-0279     
document_url: http://crdd.osdd.net/open/589/1/pushpa08.pdf