SHBG, plasma, and urinary androgens in weight lifters after a strength training.

Previous studies with different results have suggested that total and bioavailable testosterone levels are modified by physical exercise. Such changes may be related to modifications in cortisol levels and could be reflected in some urine androgens. To determine how weight lifting training may affect serum and urinary androgens, we measured total serum testosterone (T), cortisol, sex hormone binding globulin (SHBG) and urinary testosterone, epitestosterone, androsterone, and etiocholanolone, in a group of 19 elite weight lifters after 20 weeks of training.

Glutamine synthetase degradation is controlled by oxidative proteolysis in the marine cyanobacterium Prochlorococcus marinus strain PCC 9511.

Prochlorococcus is one of the most important primary producers on Earth; its unusual features and ecological importance have made it a model organism, but nutrient assimilation has received little attention. Glutamine synthetase (GS) plays a key role in nitrogen metabolism and its central position justifies the fine regulation of this enzyme. The aim of this work is to demonstrate the involvement of metal-catalyzed oxidation (MCO) in the control of the biological activity and turnover of GS from Prochlorococcus.

Glutamine synthetase from the marine cyanobacteria Prochlorococcus spp: characterization, phylogeny and response to nutrient limitation.

The regulation of glutamine synthetase (EC 6.3.1.