HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Smith, K. E. Articles by Fisher, M. T. Search for Related Content PubMed PubMed Citation Articles by Smith, K. E. Articles by Fisher, M. T. Social Bookmarking                      What's this?

J Biol Chem, Vol. 273, Issue 44, 28677-28681, October 30, 1998

Partitioning of Rhodanese onto GroEL
CHAPERONIN BINDS A REVERSIBLY OXIDIZED FORM DERIVED FROM THE NATIVE PROTEIN

From the Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, Kansas 66160

The mammalian mitochondrial enzyme, rhodanese, can form stable complexes with the Escherichia coli chaperonin GroEL if it is either refolded from 8 M urea in the presence of chaperonin or is simply added to the chaperonin as the folded conformer at 37 °C. In the presence of GroEL, the kinetic profile of the inactivation of native rhodanese followed a single exponential decay. Initially, the inactivation rates showed a dependence on the chaperonin concentration but reached a constant maximum value as the GroEL concentration increased. Over the same time period, in the absence of GroEL, native rhodanese showed only a small decline in activity. The addition of a non-denaturing concentration of urea accelerated the inactivation and partitioning of rhodanese onto GroEL. These results suggest that the GroEL chaperonin may facilitate protein unfolding indirectly by interacting with intermediates that exist in equilibrium with native rhodanese. The activity of GroEL-bound rhodanese can be completely recovered upon addition of GroES and ATP. The reactivation kinetics and commitment rates for GroEL-rhodanese complexes prepared from either unfolded or native rhodanese were identical. However, when rhodanese was allowed to inactivate spontaneously in the absence of GroEL, no recovery of activity was observed upon addition of GroEL, GroES, and ATP. Interestingly, the partitioning of rhodanese and its subsequent inactivation did not occur when native rhodanese and GroEL were incubated under anaerobic conditions. Thus, our results strongly suggest that the inactive intermediate that partitions onto GroEL is the reversibly oxidized form of rhodanese.

CiteULike

Complore

Connotea

Del.icio.us

Digg

Reddit

Technorati

This article has been cited by other articles:

				K. Y. Rhee, H. Erdjument-Bromage, P. Tempst, and C. F. Nathan S-nitroso proteome of Mycobacterium tuberculosis: Enzymes of intermediary metabolism and antioxidant defense PNAS, January 11, 2005; 102(2): 467 - 472. [Abstract] [Full Text] [PDF]

				J. Ybarra, A. M. Bhattacharyya, M. Panda, and P. M. Horowitz Active Rhodanese Lacking Nonessential Sulfhydryl Groups Contains an Unstable C-terminal Domain and Can Be Bound, Inactivated, and Reactivated by GroEL* J. Biol. Chem., January 10, 2003; 278(3): 1693 - 1699. [Abstract] [Full Text] [PDF]