Involvement of porin N,N-dicyclohexylcarbodiimide-reactive domain in hexokinase binding to the outer mitochondrial membrane.

The proportion of hexokinase that is bound to the outer mitochondrial membrane is tissue specific and metabolically regulated. This study examined the role of the N,N-dicyclohexylcarbodiimide-binding domain of mitochondrial porin in binding to hexokinase 1. Selective proteolytic cleavage of porin protein was performed and peptides were assayed for their, effect on hexokinase I binding to isolated mitochondria.

Effect of different thyroid states on mitochondrial porin synthesis and hexokinase activity in developing rabbit brain.

Voltage-dependent anion-selective channel proteins (VDACs) are pore-forming proteins found in the outer mitochondrial membrane of all eukaryotes and in brain postsynaptic membranes. VDACs regulate anion fluxes of a series of metabolites including ATP, thus regulating mitochondrial metabolic functions. Hexokinase binds to porin.

Synthesis of 3- or 4-phenyl-1,8-naphthyridine derivatives and evaluation of antimycobacterial and antimicrobial activity.

A series of 3- or 4-phenyl-1,8-naphthyridine derivatives variously substituted in the positions 2, 6 and 7 were synthesized and evaluated for in vitro evaluation for their antimycobacterial activity as part of a TAACF TB screening program under the direction of the US National Institute of Health, NIAID division. Several compounds showed an interesting activity when tested at a concentration of 6.25 microg/ml against Mycobacterium tuberculosis H(37)Rv and in particular compounds 2a, 4a,d, 8a,d and 8i, exhibit a % inhibition from 91 to 99.

Characterization of the biochemical effects of new 1, 8-naphthyridine derivatives, beta-receptor antagonists, in ventricular myocytes.

Novel derivatives of 1, 8-naphthyridine were synthesized from 7-amino-2-hydroxy-4-morpholinomethyl-1, 8-naphthyridine. The ability of the synthesized compounds to inhibit isoproterenol(ISO)-induced phosphorylation of phospholamban (PLB) was assessed. Their ability to block both beta(1) and beta(2) receptors almost completely abolished all ISO effects on phosphorylation of PLB.

Characterization of different reactive lysines in bovine heart mitochondrial porin.

Incubation of mitochondrial outer membrane porin with citraconic anhydride prior to treatment with fluorescein isothiocyanate (FITC) resulted in the labeling of a set of lysines located at a boundary between the water phase and lipid phase. The elution pattern of porin from the cation exchanger has been considered as indicative for the location of lysines. Electrical measurements after reconstitution of the modified protein in lipid bilayer membranes revealed that certain specific lysine residues are more susceptible to alterations.