General

Special Seminar in Chemistry & Engineering: Colin Bain, Durham University

Fri, 2019-03-22 13:00
Speaker: 
Colin D. Bain, Durham University
Location: 
Lynch Lecture Hall
Drops Behaving Badly

Chemistry Graduate Student Honored by ACS

Lauren Grant, a fourth year graduate student in the Mindiola group, has been selected to receive a 2019 ACS Division of Inorganic Chemistry Young Investigator Award. Recipients of this award are invited to participate in the DIC Young Investigator Symposium to be held at the Fall American Chemical Society meeting in San Diego. Recipients also receive an honorarium and a plaque.

Gilbert Stork Lecture (Andreas Pfaltz, Basel)

Mon, 2019-03-25 18:00
Speaker: 

Prof. Andreas Pfaltz

University of Basel

Location: 
Lynch Lecture Hall
Attached Document: 

Design and Screening of Chiral Catalysts for Asymmetric Sythnthesis

Biological Chemistry seminar: Gabriel Rosenblum, Weizmann Institute of Science

Thu, 2019-03-07 15:00 - 16:00
Speaker: 

Gabriel Rosenblum

Department of Structural Biology

Weizmann Institute of Science

 

"Observation of Allosteric Signaling Through DNA with Single-Molecule FRET and Cryo-EM"


Gene networks often obey complex dynamics such as pulsing and oscillations that require a nearly binary “on” and ”off” switch in gene activity. At a molecular level, a high cooperativity in the interaction between transcription factors (TFs) and DNA is key for this switch. However, how this cooperativity is achieved is unknown for many systems. We used a combination of cryo-electron microscopy (cryo-EM) and single-molecule fluorescence spectroscopy to unravel the emergence of cooperativity in the interaction between ComK, a bacterial transcription factor from Bacillus subtilis, and its promoter sequence. The promoter contains two binding sites (AT-boxes) that are separated by 18 base pairs (6 nm). Single-molecule FRET experiments show a low cooperativity for the binding to individual AT-boxes whereas the combination of two distant binding sites in the natural promoter boosts cooperativity. Importantly, the boost does not result from interactions between ComK-molecules at the two sites, as revealed by a cryo-EM structure of the ComK-DNA complex. Instead, the results unravel a new allosteric mechanism. Cooperativity between the ComK-binding sites results from an axially transmitted signal through the DNA-structure. Hence, ComK-binding to one site increases the affinity of the 18 base pair distant site. This communication forms a toggle in which complete binding, i.e., the switch from “off” to “on”, is achieved within a narrow ComK concentration range.

 


Location: 

Carolyn Hoff Lynch Room

Chemistry Complex

 

Host:  Barry Cooperman

Jessica Anna Named Sloan Fellow

Jessica Anna, Assistant Professor of Chemistry and Elliman Faculty Fellow, has been named as a 2019 Sloan Research Fellow. These two-year fellowships are awarded yearly to 126 early-career scholars in recognition of distinguished performance and a unique potential to make substantial contributions to their field.

 

The full list of Sloan Research Fellows is here.

 

 

 

Alumni Reception at APS Meeting in Boston

Tue, 2019-03-05 18:00 - 20:00
Location: 

Tuesday, March 5, 2019

6:00 – 8:00 PM

 

The Westin Boston Waterfront

Room: Revere

425 Summer Street

Boston, MA 02210

617.532.4893

 

Please RSVP to alumni@chem.upenn.edu.

Attached Document: 

Chris Murray Elected to National Academy of Engineering

Chris Murray, Richard Perry University Professor of Chemistry & Materials Science and Penn Integrates Knowledge Professor, has been elected to the National Academy of Engineering. He joins the Academy for the invention and development of solvothermal synthesis of monodisperse nanocrystal quantum dots for displays, photovoltaics, and memory.

 

Biological Chemistry seminar: Yi-Wei Chang, University of Pennsylvania

Thu, 2019-02-14 15:00 - 16:00
Speaker: 

Yi-Wei Chang

University of Pennsylvania

 

"Structural biology in situ by cellular electron cryotomography"


Electron cryotomography (ECT) enables intact cells to be visualized in 3D in an essentially native state to macromolecular (~4 nm) resolution. It has allowed us to visualize the structures of macromolecular machines in their native context inside intact cells. In many cases, such machines cannot be purified intact for in vitro study. In other cases, the function of a structure is lost outside the cell, so that the mechanism can be understood only by observation in situ. In this presentation, I will use bacterial secretion systems as examples to show how ECT can help us to understand important biological processes by doing structural biology directly inside cells.


Location: 

Carolyn Hoff Lynch Room

Cret, Chemistry Complex

Penn Chemistry Distinguished Alumni Award (Michael Brown, UT Southwestern)

Wed, 2019-05-15 16:00
Speaker: 
Michael Brown, University of Texas Southwestern Medical Center
Location: 
Lynch Lecture Hall

Edgar Fahs Smith Lecture (Amy Rosenzweig, Northwestern)

Thu, 2019-03-21 18:00
Speaker: 
Amy Rosenzweig, Northwestern University
Location: 
Lynch Lecture Hall

Department of Chemistry

231 S. 34 Street, Philadelphia, PA 19104-6323

215.898.8317 voice | 215.573.2112 fax | web@chem.upenn.edu

Syndicate content