News & Events
Chemistry Weekly Seminar - Dr. Martin St. Maurice
Posted on 2018-02-14 in Events
Apr 27, 2018
Title: A swing and a miss. Allostery and carrier domain movements in pyruvate carboxylase
Abstract: Pyruvate carboxylase (PC) is a multi-functional biotin-dependent enzyme that catalyzes the ATP-dependent carboxylation of pyruvate to oxaloacetate. The reaction occurs in two separate catalytic domains, coupled by the long-range translocation of a biotinylated carrier domain (BCCP) over ~70 Å. We used a series of hybrid PC enzymes to explore the range of catalytically productive translocation pathways for the BCCP domain. Contrary to the current model, structural and kinetic studies reveal that the BCCP domain of PC adopts multiple translocation pathways during catalysis. Furthermore, the allosteric activator, acetyl CoA, promotes one specific intermolecular carrier domain translocation pathway over all the others. These results are inconsistent with long-standing interpretations of induced conformational changes during PC-catalyzed turnover. Instead, multiple direct observations of BCCP domain positioning reveal that the carrier domain samples multiple conformations in a dynamic equilibrium. Given the similarities with increasingly well-characterized multifunctional carrier domain proteins involved in the modular synthesis of natural products, the factors influencing carrier domain movement and regulation in PC are likely to be broadly applicable to a wide range of enzyme systems.
Chemistry Special Seminar - Dr. Mukund Jha
Posted on 2019-07-16
Dr. Mukhund Jha, Nipissing University, will present a special seminar at 10:30 a.m. in Thorvaldson 205A.
Chemistry Special Seminar - Dr. John Sorensen
Posted on 2019-07-08
Dr. John Sorensen, University of Manitoba, will present a special seminar at 10:30 am in Thorvaldson 205A.
Chemistry Special Seminar - Dr. Ashok Kakkar
Posted on 2019-07-04
Dr. Ashok Kakkar, McGill University, will present a special seminar at 10:00 a.m. in Thorvaldson 159.
Chemistry Special Seminar - Dr. Jean-Francois Morin
Posted on 2019-06-27
Dr. Jean-Francois Morin of Universite Laval will present a special seminar at 10:30 am in Thorvaldson 159.
Chemistry Special Seminar - Dr. Sanjai Kumar Pathak
Posted on 2019-06-14
Dr. Sanjai Kumar Pathak, Queens College and Graduate Center of CUNY, New York will present a special seminar.
Chemistry Special Seminar - Dr. Claude Spino
Posted on 2019-05-21
Dr. Claude Spino, Universite de Sherbrooke, will present a special seminar at 11:00 a.m. in Thorvaldson 159.