The properties of the microbody malate dehydrogenase (EC 1.1.1.37) (MDH) isozyme from cotyledons of Cucumus sativus L. were compared during development. It is concluded that the isozyme remains unaltered, despite the transition from glyoxysomal to peroxisomal function that occurs during greening of the cotyledons. This conclusion is based on electrophoretic behavior, chromatographic elution fro...

Extinction promotes abstinence from drug seeking. Extinction expression is an active process, dependent on infralimbic prefrontal cortex (ilPFC). However, the neurocircuitry mediating extinction expression is unknown. Here we studied the neural mechanisms for expression of extinction of alcoholic beer seeking in rats. We first examined the pattern of activation in prefrontal cortex projections ...

Small heat shock proteins (sHSPs) and the related alpha-crystallins are ubiquitous chaperones linked to neurodegenerative diseases, myopathies, and cataract. To better define their mechanism of chaperone action, we used hydrogen/deuterium exchange and mass spectrometry (HXMS) to monitor conformational changes during complex formation between the structurally defined sHSPs, pea PsHsp18.1, and wh...

The Bacillus methanolicus methanol dehydrogenase (MDH) is a decameric nicotinoprotein alcohol dehydrogenase (family III) with one Zn(2+) ion, one or two Mg(2+) ions, and a tightly bound cofactor NAD(H) per subunit. The Mg(2+) ions are essential for binding of cofactor NAD(H) in MDH. A B. methanolicus activator protein strongly stimulates the relatively low coenzyme NAD(+)-dependent MDH activity...

PknD is one of the eleven eukaryotic-like serine/threonine protein kinases (STPKs) of Mycobacterium tuberculosis (Mtb). In vitro phosphorylation assays with the active recombinant PknD showed that the intracellular protein NAD+-dependent malate dehydrogenase (MDH) is a substrate of this kinase. MDH, an energy-supplying enzyme, catalyzes the interconversion of malate and oxaloacetate and plays c...

The results of breeding experiments with the pink salmon, Oncorhynchus gorbuscha, indicate that s-MDH-A and s-MDH-B subunits are each encoded by duplicate loci. Limited evidence suggests also that the two loci encoding for the s-MDH-A subunit are each polymorphic and linked or pseudolinked.

Molecular dynamics (MD) simulations have been carried out to study the enzymatic mechanisms of quinoproteins, methanol dehydrogenase (MDH), and soluble glucose dehydrogenase (sGDH). The mechanisms of reduction of the orthoquinone cofactor (PQQ) of MDH and sGDH involve concerted base-catalyzed proton abstraction from the hydroxyl moiety of methanol or from the 1-hydroxyl of glucose, and hydride ...

Lipid droplets (LDs) are dynamic cellular organelles responsible for the storage of neutral lipids, and are associated with a multitude of metabolic syndromes. Here we report monodansylpentane (MDH) as a high contrast blue-fluorescent marker for LDs. The unique spectral properties make MDH easily combinable with other green and red fluorescent reporters for multicolor fluorescence imaging. MDH ...

Ethyleneglycol (aminoethylether) tetra-acetic acid (EGTA) was shown to be a potent competitive inhibitor of electron transfer between methanol dehydrogenase (MDH) and its electron acceptor cytochrome cL. Addition of Ca2+ ions relieved the inhibition by removal of the inhibitory EGTA. Removal of EGTA by gel filtration completely relieved the inhibition. EGTA did not remove the tightly bound Ca2+...

Only 3 of the 6 sulfhydryl groups of native bovine heart supernatant malate dehydrogenase (S-MDH) react with p-mercuribenzoate (PMB) with no loss of enzymatic activity. In addition, prolonged incubation of S-MDH in 2.6 M urea solutions does not significantly alter the catalytic properties of the enzyme. In 2.6 M urea, however, all 6 sulfhydryl groups of the enzyme react with PMB, with attendant...