Research Highlights

Houry lab identifies a novel regulator of respiratory chain complexes

13 February 2017|

Graphical abstract_120616

An interaction between the respiratory enzyme fumarate reductase (Frd, also known as Complex II) and an ATPase has been identified in E. coli by the Houry lab. The research shows that the RavA ATPase, belonging to a poorly characterized but ubiquitous MoxR family of AAA+ ATPases, associates with the Frd respiratory enzyme through an adaptor, which the group named ViaA. […]

Ernst Lab discover new way to crystallize membrane proteins

7 February 2017|

The laboratory of Dr. Oliver Ernst has used X-ray crystallography to determine the structure of a membrane protein that never left a lipid-bilayer environment (i.e., without the use of conventional detergents). The work, published in Structure and highlighted on the Journal’s cover, was led by postdoctoral fellow Dr. Jana Broecker. Polymer-bounded lipid nanodiscs were used to extract and purify membrane proteins with their surrounding lipids and allowed […]

Ensminger lab discovers a class of bacterial effectors with novel regulatory activities

3 February 2017|

Many bacterial pathogens modulate their hosts through complex arsenals of effector proteins that are injected into host cell during infection. Indeed, the concept that effectors target host proteins and processes to modulate their activities is central to the current molecular understanding of host-pathogen interactions. Legionella pneumophila, the causative agent of a deadly pneumonia known as Legionnaires’ disease, has over 300 effectors, which is the largest known arsenal amongst bacterial pathogens. […]

Lingwood Lab discover new approach to rescue endogenous misfolded proteins

1 February 2017|

Newly made proteins which do not quite achieve the correct 3D shape in the ER are moved to the cell cytoplasm via a specific membrane pore, and broken down. Many disease causing gene mutations e.g. in cystic fibrosis, also result in misfolding of the mutant protein, and its transport though this pore, for cytoplasmic degradation. This pore is hijacked by some bacterial toxins which need to access the cytoplasm to […]

An artistic interpretation of the enzyme fluoroacetate dehalogenase binding substrate (green) in the left subunit and releasing bound water molecules (red) in the right-hand subunit.

The roles of protein dynamics and water networks in catalysis visualized

1 February 2017|

The dimeric enzyme fluoroacetate dehalogenase is one of only a handful of protein catalysts that can break the strongest bond in organic chemistry, the one between carbon and fluorine atoms, in the process transforming the highly toxic pesticide fluoroacetate into glycolate, a benign molecule.  The laboratories of Emil Pai and Scott Prosser, together with the group of Régis Pomès and collaborators in the US and Japan, have […]

Stagljar lab map interactions between receptor tyrosine kinases (RTKs) and protein tyrosine phosphatases (PTPs)

1 February 2017|

Featured on the front page of Molecular Cell, the research led by Dr. Igor Stagljar captured and mapped interactions between receptor tyrosine kinases (RTKs) and protein tyrosine phosphatases (PTPs) in human cells, leading to new and improved cancer therapies.

Read the full story on the Faculty of Medicine and The Varsity websites.

Davidson and Maxwell help discover off-switches for CRISPR

31 January 2017|

 

Featured on the cover of Cell, Biochemistry’s Dr. Alan Davidson and Dr. Karen Maxwell helped to discover how to turn off CRISPR. Read the full story.

Atomic model for the membrane-embedded motor of a eukaryotic V-ATPase

Proton pumping region of rotary ATPases revealed

3 November 2016|

In work led by postdoctoral fellow Mohammad T. Mazhab-Jafari, the Rubinstein laboratory used electron cryomicroscopy (cryo-EM) to determine the atomic structure of the membrane-bound region of a eukaryotic V-ATPase. This study, which was published in Nature, gives the first high-resolution structure for the membrane region of any rotary ATPase, a family of enzymes that includes proton pumping V-ATPases and proton-driven ATP synthases. The structure reveals several surprising features of […]

A photo of Natalie Bamford.

Bamford awarded a 2016 Vanier Canada Graduate Scholarship

3 October 2016|

Natalie Bamford, a former University of Toronto Biochemistry Specialist and current PhD student in the Howell lab, was recently awarded a prestigious Vanier Canada Graduate Scholarship from the Natural Sciences and Engineering Research Council of Canada (NSERC) to continue her studies. Natalie’s research focuses on understanding the biosynthesis of the fungal biofilm exopolysaccharide galactosaminogalactan.

“This is a new exciting project as little is known of fungal exopolysaccharide biosynthesis. I […]

Malnutrition.

Study indicates malnutrition in children may lead to severe impairments in liver function

7 September 2016|

A group led by Peter Kim and Robert Bandsma (Paediatrics) made a breakthrough published in Journal of Cell Biology and in the Journal of Hepatology in linking peroxisome function through the gene PEX2 and the cell’s response to starvation.

Malnourished children living in the same household who are given the same food to eat sometimes have stark differences in health, leading researchers to query why some severely malnourished […]

An image of models for two conformations of the AAA+ chaperone VAT, built into cryo-EM density maps.

Protein unfolding machinery visualized

9 August 2016|

Using a combined cryo-EM and solution NMR approach the laboratories of John Rubinstein and Lewis Kay have determined the structure and equilibrium distribution of two unique conformers along the ATP hydrolysis cycle of the AAA+ unfoldase VAT. The paper published in PNAS (http://www.pnas.org/content/113/29/E4190.abstract) lends insight into how this class of molecular machines are able to convert the chemical energy of ATP hydrolysis into the mechanical force required […]

An image of an atomic model of a ubiquitinated and dimethylated histone core particle with bound 53BP1 built into a cryo-EM density map.

Seeing the first steps of DNA repair

2 August 2016|

The laboratories of John Rubinstein and Frank Sicheri (Biochemistry), and Dan Durocher (Molecular Genetics) have used electron cryomicroscopy (cryo-EM) to determine the structure of the DNA-damage recognizing protein 53BP1 bound to modified nucleosome core particles. The work, published in Nature (http://www.nature.com/nature/journal/vaop/ncurrent/full/nature18951.html), was led by postdoctoral fellow Marcus Wilson and research associate Samir Benlekbir and provides the first structural insight into how dimethylation and ubiquitination of nucleosomes in […]