Record Details

Partial destabilization of native structure by a combination of heat and denaturant facilitates cold denaturation in a hyperthermophile protein.

DIR@IMTECH: CSIR-Institute of Microbial Technology

View Archive Info
 
 
Field Value
 
Title Partial destabilization of native structure by a combination of heat and denaturant facilitates cold denaturation in a hyperthermophile protein.
 
Creator Chandrayan, Sanjeev Kumar
Guptasarma, Purnananda
 
Subject QR Microbiology
 
Description Cold denaturation is a phenomenon seen in many different proteins. However, there have been no reports so far of its occurrence in hyperthermophile proteins. Here, using a recombinant triosephosphate isomerase (PfuTIM) from the hyperthermophile archaeon, Pyrococcus furiosus, we show that the heating of this protein through the low temperature side of its thermal unfolding transition in the presence of guanidinium hydrochloride (GdmCl) results in the formation of partially-disordered conformational ensembles that retain considerable native-like secondary and tertiary structure. Unlike PfuTIM itself, these thermochemically obtained partially-disordered PfuTIM ensembles display cold denaturation as they are cooled to room temperature. The protein thus shows hysteresis, adopting different structural states in a manner dependent upon the nature of the heating and cooling treatment, rather than upon the initial and final conditions of temperature and GdmCl concentration, indicating that some sort of a kinetic effect influences structure adoption and retention. The structure lost through cooling of partially-disordered PfuTIM is found to be regained through heating. The ability of GdmCl to thus apparently destabilize the highly thermodynamically and kinetically stable structure of PfuTIM (sufficiently, to cause it to display observable cold-denaturation and heat-renaturation transitions, in real-time, with cooling and heating) offers support to current ideas concerning the how hyperthermophile proteins achieve their high kinetic stabilities, and suggests that desolvation-solvation barriers may be responsible for high kinetic stability.
 
Publisher Wiley
 
Date 2008-08
 
Type Article
PeerReviewed
 
Format application/pdf
 
Identifier http://crdd.osdd.net/open/593/1/guptasarma08.14.pdf
Chandrayan, Sanjeev Kumar and Guptasarma, Purnananda (2008) Partial destabilization of native structure by a combination of heat and denaturant facilitates cold denaturation in a hyperthermophile protein. Proteins, 72 (2). pp. 539-546. ISSN 1097-0134
 
Relation http://onlinelibrary.wiley.com/doi/10.1002/prot.22077/pdf
http://crdd.osdd.net/open/593/