Interaction of non-myristoylated NADH-cytochrome b5 reductase with cytochrome b5-dimyristoylphosphatidylcholine vesicles.

نویسندگان

  • P Strittmatter
  • J M Kittler
  • J E Coghill
  • J Ozols
چکیده

An expression vector for NADH-cytochrome b5 reductase containing a thrombin cleavage site directly before the N-terminal glycine residue of the flavoprotein was used to isolate the non-myristoylated enzyme by thrombin cleavage of the initial fusion protein of a short segment of the multiple cloning site of the plasmid vector and the reductase. This flavoprotein preparation, containing only the 28-residue N-terminal peptide segment of the membrane-binding domain of the mammalian enzyme, binds to phospholipid vesicles and interacts with membrane-bound cytochrome b5. The effect of N-myristoylation of the enzyme therefore appears to be limited to facilitating and stabilizing interactions with phospholipid vesicles. However, the relatively short intervening peptide sequence that separates the crucial peptide membrane-binding domain from lysine 41, which has been implicated in the active-site interaction with cytochrome b5 (Strittmatter, P., Kittler, J. M., Coghill, J. E., and Ozols, J. (1992) J. Biol. Chem. 267, 2519-2523), provides some limitation of the distance from the membrane surface for the interactions required for rapid electron transfer from the flavin of the reductase to the heme of cytochrome b5.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Cytochrome b5 reductase is the component from neuronal synaptic plasma membrane vesicles that generates superoxide anion upon stimulation by cytochrome c

In this work, we measured the effect of cytochrome c on the NADH-dependent superoxide anion production by synaptic plasma membrane vesicles from rat brain. In these membranes, the cytochrome c stimulated NADH-dependent superoxide anion production was inhibited by antibodies against cytochrome b5 reductase linking the production to this enzyme. Measurement of the superoxide anion radical generat...

متن کامل

The interaction of NADH-cytochrome b5 reductase and cytochrome b5 bound to egg lecithin liposomes.

Incubation of liposomes prepared by sonication of egg lecithin with the amphipathic form of cytochrome b5 results in the binding of a maximum of 244 molecules of cytochrome b5 per liposomal vesicle. Interactions of the phospholipid with the hydrophobic segment of cytochrome b5 are involved in this binding which does not disrupt the liposome. When a small amount of NADH-cytochrome b5 reductase i...

متن کامل

Molecular construction of NADH-cytochrome b5 reductase inhibition by flavonoids and chemical basis of difference in inhibition potential: Molecular dynamics simulation study

NADH-cytochrome b5 reductase, a flavoprotein, plays a central role in many diverse metabolic reactions. NADH-cytochrome b5 reductase has been shown to be responsible for the generation of free radicals from heterocyclic amines. Flavonoids compounds share remarkable similarity in structure but showed differences in their cytochrome b5 reductase inhibition pattern. Our molecular dynamics simulati...

متن کامل

NADH cytochrome b5 reductase and cytochrome b5 catalyze the microsomal reduction of xenobiotic hydroxylamines and amidoximes in humans.

Hydroxylamine metabolites, implicated in dose-dependent and idiosyncratic toxicity from arylamine drugs, and amidoximes, used as pro-drugs, are metabolized by an as yet incompletely characterized NADH-dependent microsomal reductase system. We hypothesized that NADH cytochrome b5 reductase and cytochrome b5 were responsible for this enzymatic activity in humans. Purified human soluble NADH cytoc...

متن کامل

A role for N-myristoylation in protein targeting: NADH-cytochrome b5 reductase requires myristic acid for association with outer mitochondrial but not ER membranes

N-myristoylation is a cotranslational modification involved in protein-protein interactions as well as in anchoring polypeptides to phospholipid bilayers; however, its role in targeting proteins to specific subcellular compartments has not been clearly defined. The mammalian myristoylated flavoenzyme NADH-cytochrome b5 reductase is integrated into ER and mitochondrial outer membranes via an anc...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • The Journal of biological chemistry

دوره 268 31  شماره 

صفحات  -

تاریخ انتشار 1993