The North Jersey ACS NMR Topical Group is pleased to presents its January meeting at Rutgers, Wednesday, January 10, 2018 [ register ]
Featured Presentation
Qi Gao
Structure Elucidation Group, Merck & Co., Inc.
“From Protein-Ligand Interactions to Small Molecule Structure Elucidation”
Abstract
Glycoprotein-glycosaminogycan (GAG) complexes have important functions in cell migration, proliferation and cancer progression. Characterization of these systems is best done on properly glycosylated forms produced by expression of the proteins in mammalian cell culture. Mammalian protein characterization by traditional NMR methodology is challenging since the uniform isotopic labeling needed to expedite NMR resonance assignment becomes extraordinarily expensive; and direct in vivo deuteration of proteins is detrimental to cell growth. In this presentation, I will describe an alternative labeling methodology based on sparse labeling with single isotopically enriched amino acids. This approach enhances the NMR resolution while reducing expense in protein expression. The primary limitation of sparse labeling is that through-bond connectivities between isotopically labeled residues no longer exist. Consequently, traditional triple resonance assignment approaches are not viable. To overcome this obstacle, a new strategy was developed to assign the 1H, 13C, and 15N resonances for a sparsely labeled protein sample. This strategy uses a genetic algorithm to search for an optimal pairing of HSQC crosspeaks with labeled sites based on experimental and predicted values of chemical shifts, nuclear Overhauser effects (NOEs) and residual dipolar couplings (RDCs). Once the assignments are available for each labeled site, structural information encoded in NMR data, including chemical shift perturbation, STD, trNOE, RDC, and paramagnetic effects, combined with multiple computational software platforms is utilized to elucidate their interactions with corresponding ligands. Signaling glycoproteins Robo1 and type IIa receptor protein tyrosine phosphatase LAR interacting with GAGs will be presented as examples to apply this combined methodology. In addition, an overview of the Structure Elucidation Group at Merck will be presented.
Program
6:00 pm Dinner
7:00 pm Seminar
Dinner Cost:
$15 employed / $5 students, postdoc, retired, unemployed. No charge for seminar only.
Meeting Venue
Where: CABM (Center for Advanced Biotechnology and Medicine)
Rutgers, 679 Hoes Lane West
Piscataway, NJ 08854 [ directions ]
Parking: Parking will be available in the front of CABM (see map link given above under Directions)
Questions:
Mary.Harner@bms.com (Chair)
or qi.gao1@merck.com (Co-Chair)
Register:
Please register online here
or via e-mail to Mary.Harner@bms.com or qi.gao1@merck.com
