- 01.08.2019 -
S3 SEMINAR Prof. Sander Tans
Date and Time: Thursday August 1, 2019 - 11.00
Venue: S3 Seminar Room, Third Floor, Physics Building, FIM Department
Speaker: Professor Sander Tans
FOM Institute for Atomic and Molecular Physics [AMOLF] Amsterdam, The Netherlands
Title: Chaperone-guided folding of single proteins
Abstract:Chaperones are well known to be central to the folding of larger proteins in cells. But it has been difficult to determine whether the folding process is affected directly. Much of the current evidence suggests that chaperones instead help folding indirectly, by suppressing aggregation between protein molecules. Moreover, the principles that could underlie direct folding assistance remain unclear. We have explored this question by focusing on single proteins using optical tweezers. We have previously studied the chaperones SecB, trigger factor, and Hsp70, the latter two of which have shown surprising ability to bind and stabilize partially folded structures, and thus are able to act throughout the folding pathway up to the near native state. In this presentation I will discuss some of these earlier findings as well as more recent results on other chaperone systems, including GroEL and ClpB, as well as ribosomal chaperone activity.
Alternative modes of client binding enable functional plasticity of Hsp70, A. Mashaghi, S. Bezrukavnikov, D.P. Minde, A.S. Wentink, R. Kityk, B. Zachmann-Brand, M.P. Mayer, G. Kramer, B. Bukau and S.J. Tans, Nature 539, 448–451 (2016).
Reshaping of the conformational search of a protein by the chaperone trigger factor, Mashaghi A, Kramer G, Bechtluft P, Zachmann-Brand B, Driessen AJ, Bukau B, Tans SJ, Nature 500, 98-101 (2013).
Direct observation of chaperone-induced changes in a protein folding pathway, Philip Bechtluft, Ruud van Leeuwen , Matthew Tyreman, Danuta Tomkiewicz, Nico Nouwen, Harald Tepper, Arnold Driessen, and Sander J. Tans, Science 318, 1458-61 (2007).
Host: Prof. Ciro Cecconi