The responses of rat neocortical neurons in vitro to iontophoretically applied N-methyl-D-aspartate (NMDA) were investigated by means of intracellular recording in the presence and absence of extracellular magnesium ions (Mg2+). At Mg2+-concentrations of 1.3 mM the neurons responded with a depolarization accompanied by an increase in membrane resistance. Upon removal of Mg2+ the NMDA-induced de...

MgATP of CaATP is the substrate of the Mg-Ca-ATPase. At low Mg2+- or Ca2+-concentrations the ATPase is activated by Mg2+ or Ca2+, the activator being essential for activity. At higher Mg2+- or Ca2+-concentrations the Mg-Ca-ATPase is inhibited competitively. Thus the real Km is smaller than reported in the literature. H+ competes with Mg2+ or Ca2+ for the metal binding sites.

Salmonella typhimurium has three distinct transport systems for Mg2+: CorA, MgtA, and MgtB. The mgtCB operon encodes two proteins, MgtC, a hydrophobic protein with a predicted molecular mass of 22.5 kDa, and MgtB, a 102-kDa P-type ATPase Mg2+ transport protein. The mgtCB locus has been identified as part of a new Salmonella pathogenicity island, SPI-3. Transcription of mgtCB is regulated by ext...

Zebrafish photoreceptor cells express six guanylate cyclase-activating proteins (zGCAPs) that share a high degree of amino acid sequence homology, but differ in Ca(2+)-binding properties, Ca(2+)-sensitive target regulation and spatial-temporal expression profiles. We here study a general problem in cellular Ca(2+)-sensing, namely how similar Ca(2+)-binding proteins achieve functional selectivit...

Riboswitches are genetic regulatory elements that control gene expression depending on ligand binding. The guanine-sensing riboswitch (Gsw) binds ligands at a three-way junction formed by paired regions P1, P2, and P3. Loops L2 and L3 cap the P2 and P3 helices and form tertiary interactions. Part of P1 belongs to the switching sequence dictating the fate of the mRNA. Previous studies revealed a...

introduction: photonics refers to the technology of generating and harnessing light and other forms of radiant energy whose quantum unit is the photon. photonic technology in the meridian and acupoints research has shown the unique advantages, by which the microcosmic material basis and macroscopic phenomena research can be integrated to interpret the occurrence of propagated sensation along me...

Sheep liver cytoplasmic aldehyde dehydrogenase is strongly inhibited by Mg2+, Ca2+ and Mn2+. The inhibition is only partial, however, with 8-15% of activity remaining at high concentrations of these agents. In 50 mM-Tris/Hcl, pH 7.5, the concentrations giving half-maximal effect were: Mg2+, 6.5 micrometers; Ca2+, 15.2 micrometers; Mn2+, 1.5 micrometer. The esterase activity of the enzyme is not...

Mg2+ regulates many physiological processes and signalling pathways. However, little is known about the mechanisms underlying the organismal balance of Mg2+. Capitalizing on a set of newly generated mouse models, we provide an integrated mechanistic model of the regulation of organismal Mg2+ balance during prenatal development and in adult mice by the ion channel TRPM6. We show that TRPM6 activ...

Dyspeptic symptoms are quite common in patients on long-term hemodialysis, and Helicobacter pylori is thought to play an important role in the pathogenesis of active gastritis and other upper gastrointestinal mucosal lesions in these patients. This study investigated the probable association of serum magnesium (Mg2+) with H pylori infection in patients on maintenance therapy. H pylori specific ...