phosphate transport

N-Ethylmaleimide (NEM) is a reagent for alkylation of free sulfhydryl groups, a cysteine protease inhibitor used in experimental biochemistry. N-Ethylmaleimide is also a deubiquitinating enzyme inhibitor that specifically inhibits phosphate transport in mitochondria.

Diethylumbelliferyl phosphate (DEUP) is a potent and selective inhibitor of cholesterol esterase that does not inhibit protein kinase A activity in vitro. It disrupts steroidogenesis by blocking cholesterol transport to mitochondria in steroidogenic cells, with an IC50 of 11.6 μM. This compound may also limit the absorption of dietary cholesterol.

NADP+ is the oxidized form of the electron donor nicotinamide adenine dinucleotide phosphate . It serves as a cofactor in various biological reactions. In addition, the balance between these reduced and oxidized forms plays key roles in diverse cellular functions, including cell survival, the maintenance of redox status, and intracellular signaling. For example, binding of NADP+ to β-subunits of Kv channels activates ion transport, whereas NADPH stabilizes channel inactivation. NADP+ is biosynthesized from NAD+ by NAD kinase, with ATP as the phosphoryl donor.

4-Deoxypyridoxine (4-DPD) is a vitamin B6 antimetabolite with diverse biological activities. It inhibits transport of pyridoxine , pyridoxal, and pyridoxamine in and reduces growth of S. carlsbergensis cells. 4-DPD inhibits sphingosine-1-phosphate (S1P) lyase and reduces cyclic stretch-induced apoptosis in alveolar epithelial MLE-12 cells. 4-DPD (5 mg, i.p.) reduces lysyl oxidase activity by 26% and reduces collagen and elastin crosslinking, resulting in limb abnormalities in chick embryos. It decreases latency to first seizure in mice (ED50 = 1 mmol kg) and increases the occurrence and duration of myoclonic responses in baboons with photosensitive epilepsy. 4-DPD reduces TNF-α and IL-6 production in mice infected with T. spiralis.