Metabolite profiling of pea roots in response to phosphate availability.

The arbuscular mycorrhizal (AM) symbiosis is a mutualistic association between soil fungi (Glomeromycota) and roots of most plant species. A recent study showed that high phosphate fertilization could inhibit mycorrhizal colonization at a very early stage, before hyphopodium formation. The authors proposed that inhibiting and/or stimulatory compounds might be present in roots grown under high phosphate or low phosphate, respectively.

CB1 receptor-mediated control of the release of endocannabinoids (as assessed by microdialysis coupled with LC/MS) in the rat hypothalamus.

In the present study, we examined the occurrence and potential regulation of endocannabinoid release by cannabinoid CB1 receptors in the rat brain. To this end, we developed a highly sensitive (limit of sensitivity 30-300 amol) new analytical method, combining online brain microdialysis with solid-phase extraction-liquid chromatography-tandem mass spectrometry, which allowed the detection in real time of trace amounts of endocannabinoids in the extracellular fluid. In the hypothalamus, anandamide and 2-arachidonoyl-glycerol release was stimulated following depolarization via local administration of K(+), with or without addition of Ca(2+), or glutamate application.

Mycobacterium tuberculosis phoP mutant: lipoarabinomannan molecular structure.

Mycobacterium tuberculosis encodes two-component signal systems. Recently, it was established that the viability of the M. tuberculosis phoP mutant is attenuated in the mouse, suggesting the requirement of the phoP gene for M.