Author: Brooke Andrews

Last week’s JACS highlighted Morgan’s recent paper, “Activity-Related Microsecond Dynamics Revealed by Temperature-Jump Förster Resonance Energy Transfer Measurements on Thermophilic Alcohol Dehydrogenase.” The Spotlight summary, included below, underscores the uniqueness of the timescales we access in our lab and the overall importance of understanding enzyme dynamics in catalysis.  Congrats on an outstanding paper, Morgan!

Making Sense of Protein Motion in Enzymes, Erika Gebel Berg (Ph.D.)

In recent years, scientists have come to appreciate that orchestrated protein motions are key drivers of enzyme activity. However, the details can be difficult to work out due to experimental limitations. Protein dynamics occur on multiple time scales, ranging from picoseconds to milliseconds, so measurement techniques must be carefully selected to probe the time scale of interest. Thomas Spiro, R. Brian Dyer, Judith Klinman, and colleagues use time-resolved temperature-jump FRET spectroscopy to probe the dynamics of thermophilic alcohol dehydrogenase, an enzyme model of the link between protein motion and activity (DOI: 10.1021/jacs.7b12369).

Previous researches in the Klinman Lab had indicated that protein motions facilitate the enzyme’s activity at temperature above 30 °C, but the timing and position of the motions was unknown. Now, by monitoring the energy transfer between NADH, the enzyme cofactor, and a nearby tryptophan side chain, the researchers observe a fast motion involving the enzyme active site that turns on above 30 °C. The fast relaxation rate is not detected at lower temperatures where the enzyme activity is compromised. This result implicates a link between thermally equilibrated, microsecond protein motions and the creation of active site configurations that facilitate catalysis. The work is a major step forward in understanding the functional role of enzyme dynamics.

Last week, Dr. Dyer visited the NIH in Bethesda, Maryland, at the invitation of Protein Conformation and Dynamics senior investigator Jennifer Lee. During the visit, Dyer gave a talk entitled “Membrane Protein Dynamics,” which was preceded by a poetic introduction that summarizes the research performed in our lab:

This new year brought the Dyer Lab a new, yet familiar face, as Alexia joins the lab as a graduate research student. Following her tenure as an undergrad in the group, she will be continuing her work on protein-membrane interactions, examining the requisite dynamics for viral entry and propagation. 

The arrival of 2018 also marked the exit of Erin, our beloved group member-turned-postdoc, who has moved on to take a prestigious clinical chemistry fellowship at the University of Kentucky College of Medicine’s Department of Pathology and Laboratory Medicine.  The move embraces her past clinical experience, current chemical and biophysical expertise, and love of thoroughbred horses. 

Best of luck to both of you!

As the third rotation period begins, we say goodbye and good luck to Rui, who worked with Gokul on the expression of supercharged GFP. We also welcome Sara, who will spend the next five weeks working with Monica and Bryant, team energy. Glad to have you here, Sara!

Last weekend, Monica and Bryant traveled to Salt Lake City, Utah, to help with Emory Chemistry recruiting at SACNAS. While they were there, Monica also presented her research in a talk, titled “Events in Photocatalysis: Probing the Electron Transfer Mechanism at the Quantum Dot-Mediator Interface.”

Meanwhile, Brooke, Morgan, and Rachel (Team Enzyme) traveled to Tucson, Arizona with Dr. Dyer to participate in the annual NIH Program Project Review. At the meeting, each presented their work during a poster session at the University of Arizona alongside collaborators from the labs of Dr. Steve Schwartz (U of AZ), Dr. Robert Callender (Albert Einstein College of Medicine), and Dr. Vern Schramm (Albert Einstein College of Medicine). 

In addition to the updates on the enzyme research, the group also received a private tour of the University’s Richard F. Caris Mirror Lab, where the seven 8.4 meter honeycomb glass mirrors are currently being created for the Giant Magellan Telescope in Chile.