Highlights

Congratulations to undergraduates George Alyateem, Harrison Vogel and Brent Chesson, each recipients of summer research grants from North Carolina Biotechnology Center, Howard Hughes Medical Institute, and NSF REU Nanosure (resectively)!

Joining these three undergraduates this summer are recent BS Chemistry graduate, Matthew Van Vorst (NIH support), and currrent chemistry undergraduates David Ardakani and Jay Cox.

This summer our group will be hosting two high school students: Matthew Jordan, a rising senior from the North Carolina School of Science and Math (arguably the best high school in the country!) and an ACS project SEED recipient Carly Prevatte from Audrey Kell HS.

Graduate student, Jon Trullinger, will be busy finishing his thesis work and writing up!

Jon Trullinger and Matthew Van Vorst win 3rd place in the poster competition at regional ACS meeting sponsored by Syngenta in Greensboro, NC

Over 200 colleagues attended 10th Annual Poster Vendor Night Exhibit which was held at Syngenta on April 13th. This event drew the largest attendance for a technical meeting hosted by the Central NC Section of the ACS. Sixteen vendors displayed their products and forty-eight posters highlighting chemical research in the Triad, RTP and Charlotte regions were presented. The local section awarded prizes for the best student posters. The judging process was difficult because of the high quality of all of the student posters.

Awards were given for:

First Place: Human 2-keto-4-hydroxy-glutarate Aldolase (KHGA), a Promising New Target for Modulating Oxalate Production in Primary Hyperoxaluria Patients ,Travis Riedel and Dr. W. Todd Lowther, Department of Biochemistry, Wake Forest University School of Medicine

Second Place: Effects of Resveratrol and Galangin on hCYP1A1 and hCYP1B1 Activation of Benzo[a]Pyrene (B[a]P) and B[a]P(-)7,8-diol (BPD) to Toxic and Mutagenic Metabolites, Patricia D. Durant1, Sandra Leone-Kabler2, Alan J. Townsend2 1 Department of Molecular Medicine & Translational Sciences, Wake Forest University School of Medicine, 2 Department of Biochemistry, Wake Forest University School of Medicine

Third Place: Characterization of Protein Structure and Stability in the Presence of Ionic Liquids, Matthew Van Vorst, Jonathan Trullinger and Joanna Krueger, Department of Chemistry, University of North Carolina at Charlotte

Gelsolin and actin from crystal structure shown as black and blue ribbon with modeled SANS data for gelsolin and the actin dimer of the GA2 complex shown as dark grey and light grey balls, respectively.

Master’s student, Ryan Oliver, finished writing and successfully defended his thesis work, (see abstract below). He was accepted into the Ph. D. program in Chemistry at the U. Virgina beginning in the Fall 2010. He will move to Charlottesville, VA in June and begin working with Dr. Linda Columbus, who has offered him a summer position in his lab.

Contrast is a demonstration on the concept of light scattering and contrast matching that Ryan used in his defense.

Constraints for Building Structural Models of Gelsolin, an Actin Dimer, and their Complex in Solution using Small-angle Scattering Data

Abstract:

Actin, a 42kDa globular protein commonly recognized for its role in muscle cell contraction, is an essential component of the cellular cytoskeleton in nearly all eukaryotic cells. In non-muscle cells, actin forms dynamic networks responsible for vital cellular functions such as intracellular localization and transport, as well as cellular motility events. Actin’s role in these processes is achieved through its ability to rapidly polymerize to filamentous (F-)actin and de-polymerize back to monomeric globular (G-)actin in a tightly-regulated fashion. Read more…

Jon Trullinger presents his research at the National ACS meeting in San Fransico, CA March 2010

Abstract:

The native, folded structure of a protein is known to exhibit limited shelf life while in aqueous solutions. The mechanism for this observed instability may be related to time-dependent aggregation phenomena. Recent investigations into methodologies that increase the conformational stability of proteins involve solubilization of proteins in the presence of ionic liquids (ILs), salts that exist as liquids at or near room temperature. We have explored ILs as a means to increase the shelf life of several proteins. We report herein structural and functional data collected on these proteins in a concentration series of ionic liquids. Utilizing a well-established fluorescence assay to follow the rate of polymerization and depolymerization of actin, it was found that self-association slowed significantly in 1% IL and was not observed in as little as 10% IL. Using circular dichroism, fluorescence, and SAXS we will characterize the relationship between these changes and protein structure.

Seven UNC Charlotte undergraduate and two Master’s students commit to a semester of biophysical research at UNC Charlotte. Pictured is (left to right, bottom row) undergraduate students Navid Ardakani, Harrison Vogel (Kalamazoo College), Jay Cox, and Brent Chesson. (top row) Dr. Krueger, graduate student Jon Trullinger, with undergraduates Matthew Van Vorst and Arthur Huntley. Also in the group is Ryan Oliver (MS*10) and BS Chemistry undergraduate HaeNa Chung (not pictured).

Spring 2010 Krueger Research Team

Guest Undergraduate Research Student, Harrison Vogel, is a junior at Kalamazoo College, my alma mater, who came to experience a research environment during his semester off from Jan – March. His work was presented at the regional ACS poster competition in Greensboro. He received a HHMI summer research fellowship and will be back to finish his senior independent project, a requirement for all graduates of Kalamazoo College.

Graduate student, Ryan Oliver (not pictured) spent the semester writing up his thesis work, which he successfully defended on April 7, 2010. He was accepted into the NIST neutron scattering summer school for May 10 -14. Thomas Walsh Research Fellow, Jon Trullinger, continued his Master’s thesis work, which he presented at the National ACS meeting in San Francisco, March 24, 2010 as well as the regional ACS poster competition held at Syngenta in Greensboro, NC.

Chris Boone celebrates after successfully defending his Master’s thesis, June 25, 2009

Master’s student, Christopher Daniel Boone, finished writing and successfully defended his thesis work, (see abstract below). He was accepted into the Ph. D. program at U. Florida beginning in the Fall 2010. He will move to Gainesville, Fl in August.

Conformational change within full-length HIV-1 gp120 upon ligation with T-cell receptor CD4 and neutralizing antibody IgG1 b12

Abstract:

Viral membrane glycoprotein gp120 is the key surface coat protein involved in HIV-1 human cellular recognition and initiating viral entry into the host cell. This viral entry is initiated by binding of gp120 to the first ectodomain (D1) of the hosts four domain T-cell receptor CD4. After binding with CD4, the variable V3 loop of gp120 is extended out to ligate with a coreceptor on the T-cell surface, CXCR4 or CCR5. Small-angle X-ray scattering (SAXS)-derived structural perimeters and models of the unliganded soluble CD4 constructs (sCD4D1-D2, sCD4D1-D4) agreed well with previously reported crystallographic data with sCD4D1-D4 adapting a ‘Z’-conformation in solution. Likewise, SAXS data analyses of HIV-1SF162 gp120 ligated with both sCD4 constructs revealed a conformational change in the D2-D3 linker region within sCD4D1-D4 which rotates the D3/D4 subdomains with respect to D1/D2 subdomains, changing the overall shape of sCD4D1-D4 from a ‘Z’- to a ‘U’-configuration upon binding gp120. This conformational change of sCD4D1-D4 upon binding HIV-1 gp120 is believed to be the key event that brings the extended V3 loop of gp120 into close enough proximity with the T-cell coreceptor which then initiates viral entry into the host cell.Read more…