Nicotine is a main alkaloid in tobacco and is also the primary toxic compound in tobacco wastes. It can be degraded by bacteria via either pyridine pathway or pyrrolidine pathway. Previously, a fused pathway of the pyridine pathway and the pyrrolidine pathway was proposed for nicotine degradation by Agrobacterium tumefaciens S33, in which 6-hydroxy-3-succinoylpyridine (HSP) is a key intermediat...

Ovotransferrin is one of the major egg white proteins that have antimicrobial activity as well as iron binding capability. The objective of this study was to develop a simple and easy method to separate ovotransferrin without using organic solvents. Egg white was separated from yolk, added in a 1:1 ratio to distilled water (DW), and then homogenized. The ovomucin in the diluted egg white was re...

The gastric pathogen Helicobacter pylori possesses a highly active urease to support acid tolerance. Urea hydrolysis occurs inside the cytoplasm, resulting in the production of NH3 that is immediately protonated to form NH4 (+). This ammonium must be metabolized or effluxed because its presence within the cell is counterproductive to the goal of raising pH while maintaining a viable proton moti...

7-Azabicyclo[2.2.1]heptane-2-carboxylic acid 11 was prepared in enantiopure form, and its catalytic potential in the direct aldol reaction between acetone and 4-nitrobenzaldehyde was assessed. The bicyclic system was found to be more selective than its monocyclic analogue beta-proline 5b. A comparative density functional theory study of proline 1, beta-proline 5b, and 11 in the latter reaction ...

Structural requirements of N-blocked L-proline derivatives as specific inhibitors for prolyl endopeptidase were investigated using a series of substrate analogs. Replacement of L-proline by its D-isomer remarkably reduced the inhibition. Introduction of a sulfur atom in proline and/or in the penultimate pyrrolidine rings significantly increased the inhibition, but the introduction of oxygen rat...

A study of the phase transition behavior of mixed ammonium sulfate – malonic acid aerosols C. F. Braban and J. P. D. Abbatt Centre for Atmospheric Sciences, Department of Chemistry, Lensfield Road, University of Cambridge, Cambridge, CB2 1EW, UK Department of Chemistry, University of Toronto, Toronto, ON, M5S 3H6, Canada Received: 22 March 2004 – Accepted: 3 May 2004 – Published: 2 June 2004 Co...