Biomedical subjects

Benjamin J Gross

Publications and source records attributed to Benjamin J Gross.

3 recordsLinked to original sources

PubMed2006

Locating hydrogen atoms in single crystal and uniaxially aligned amino acids by solid-state NMR.

We demonstrate a novel method to locate hydrogen atoms in amino acids, which involves measuring the C(alpha)H(alpha) bond vector geometry through orientationally dependent dipolar coupling frequencies measured by Lee-Goldburg cross polarization (LGCP). A 2D LGCP experiment is used to measure the polar angle of the C(alpha)H(alpha) bond vector in a single crystal of the model compound L-alanine. It is also demonstrated that by coupling the 13C(alpha)1H(alpha) LGCP experiment to a 13C(alpha)15N REDOR experiment, one can determine the complete three-dimensional geometry of the C(alpha)H(alpha) and C(alpha)N vectors in a single crystal. These measurements allow for location of hydrogen atoms in crystalline biological macromolecules.

Algorithms↗

PubMed2005

Discovery of O-GlcNAc transferase inhibitors.

O-GlcNAcylation of serine and threonine residues is a dynamic and essential post-translational modification involved in signaling pathways in eukaryotes. Studies of O-GlcNAcylation would be aided by small-molecule inhibitors of O-GlcNAc transferase (OGT), the sole enzyme know to mediate this modification, but discovery of such molecules has been hampered by poor expression of cloned OGT and lack of suitable high-throughput screens. This Communication describes the development an expression system to access large amounts of the catalytic domain of OGT and the implementation of a fluorescence-based substrate analogue displacement assay that has led to the discovery of a set of OGT inhibitors. This work lays the foundation for both structural and functional analysis of the catalytic domain of OGT.

Catalysis↗

PubMed2005

Structure determination of aligned systems by solid-state NMR magic angle spinning methods.

Single crystal rotational echo double resonance (REDOR) experiments can be used to determine the three-dimensional orientation of heteronuclear bond vectors in an amino acid, as well as the crystal's orientation relative to the rotor fixed frame (RFF). We also demonstrate that for samples uniaxially aligned along the rotor axis, the polar tilt angle of a bond vector relative to the RFF can be measured by use of an analytical expression that describes the REDOR curve for that system. These bond orientations were verified by X-ray indexing of the single crystal sample, and were shown to be as accurate as +/- 1 degrees .

Alanine↗