Mutants of Agrobacterium tumefaciens virG gene that activate transcription of vir promoter in Escherichia coli.

The virA and virG two-component regulatory system is essential for transcriptional activation of virulence (vir) genes in Agrobacterium tumefaciens in the presence of inducer molecules. The VirA/VirG mediated vir gene transcription depends on a specific interaction between the C-terminal domain of the alpha subunit (RpoA) of A. tumefaciens RNA polymerase (RNAP) and N-terminal domain of the VirG.

Structural insights and functional implications of choline acetyltransferase.

The biosynthetic enzyme for the neurotransmitter acetylcholine, choline acetyltransferase (ChAT) (E.C. 2.

Structural and mutational characterization of L-carnitine binding to human carnitine acetyltransferase.

We report the crystal structure of a binary complex of human peroxisomal carnitine acetyltransferase and the substrate l-carnitine, refined to a resolution of 1.8 Angstrom with an R(factor) value of 18.9% (R(free)=22.

A two-dimensional imaging biosensor to monitor enhanced brain glutamate release stimulated by nicotine.

In this study, we have imaged and monitored real-time release of neurotransmitter glutamate from mouse brain slices stimulated by nicotine and physiological salts using a newly developed two-dimensional (2D) imaging biosensor. Nicotine, the addictive substance contained in cigarettes and other tobacco baring products, affects human body through interactions with both central and peripheral nervous system receptors and exists in various concentrations in body organs including the brain. The 2D imaging biosensor, designed for sensitive glutamate monitoring, is prepared through the use of a flat silica plate that is covalently attached with an enzyme, glutamate dehydrogenase (GDH).

Crystallization and preliminary X-ray crystallographic studies on recombinant rat choline acetyltransferase.

Choline acetyltransferase (ChAT) catalyzes the biosynthesis of the neurotransmitter acetylcholine from acetyl-CoA and choline in cholinergic neurons. Rat ChAT (rChAT) was overexpressed in Escherichia coli, purified by affinity chromatography and crystallized. Diffraction data were collected from a single crystal under cryoconditions at the F1 beamline at the Cornell High Energy Synchrotron Source, with a maximal useful diffraction pattern to 1.

Two-dimensional imaging biosensor for the monitoring of lactate released from brain slices.

Real-time monitoring of lactate release from brain slices has been studied with an optical two-dimensional (2D) imaging biosensor. The 2D biosensor is prepared by direct immobilization of lactate dehydrogenase (LDH) molecules onto a flat silica glass surface through a covalent binding mechanism. The biosensor is able to spatially differentiate lactate concentration variations with conventional optical microscopic spatial resolution.

Structure of human carnitine acetyltransferase. Molecular basis for fatty acyl transfer.

Carnitine acyltransferases are a family of ubiquitous enzymes that play a pivotal role in cellular energy metabolism. We report here the x-ray structure of human carnitine acetyltransferase to a 1.6-A resolution.

Crystallization and preliminary X-ray crystallographic studies on recombinant human carnitine acetyltransferase.

In this paper, the purification, crystallization and preliminary X-ray crystallographic studies of human carnitine acetyltransferase are reported. Recombinant human carnitine acetyltransferase crystals were grown by the hanging-drop vapor-diffusion method and belong to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 137.65, b = 84.

Protein microarrays to detect protein-protein interactions using red and green fluorescent proteins.

Proteomics, the study of protein function on a global scale, will play an important role in furthering our understanding of gene functions, complex biological pathways, and discovery of novel drug targets. A number of techniques have been developed for proteomic studies to identify and analyze proteins, compare protein expression levels, and study protein-protein interactions. Recent developments have applied a DNA array-type approach to immobilize proteins on a surface for high-throughput analysis.