Ligand binding induces an ammonia channel in 2-amino-2-desoxyisochorismate (ADIC) synthase PhzE.

PhzE utilizes chorismate and glutamine to synthesize 2-amino-2-desoxyisochorismate (ADIC) in the first step of phenazine biosynthesis. The PhzE monomer contains both a chorismate-converting menaquinone, siderophore, tryptophan biosynthesis (MST) and a type 1 glutamine amidotransferase (GATase1) domain connected by a 45-residue linker. We present here the crystal structure of PhzE from Burkholderia lata 383 in a ligand-free open and ligand-bound closed conformation at 2.

Effect of O-superfamily conotoxin SO3 on synchronized spontaneous calcium spikes in cultured hippocampal networks.

SO3 belongs to the O-superfamily of conotoxins and is known to have analgesic effects in experimental animals. In order to explore the mechanism of its potential pharmacological actions, the effect of SO3 on synchronized spontaneous calcium spikes was examined in cultured hippocampal networks by calcium imaging. Spontaneous oscillations of intracellular concentrations of calcium (Ca(2+)) in the form of waves and spikes are found in cultured hippocampal networks.