The survival of the malaria parasite Plasmodium falciparum is dependent upon the de novo biosynthesis of pyrimidines. P. falciparum dihydroorotate dehydrogenase (PfDHODH) catalyzes the fourth step in this pathway in an FMN-dependent reaction. The full-length enzyme is associated with the inner mitochondrial membrane, where ubiquinone (CoQ) serves as the terminal electron acceptor. The lipophili...

Mitochondrial dysfunction is a fundamental abnormality in the vascular endothelium and smooth muscle of patients with pulmonary arterial hypertension (PAH). Because coenzyme Q (CoQ) is essential for mitochondrial function and efficient oxygen utilization as the electron carrier in the inner mitochondrial membrane, we hypothesized that CoQ would improve mitochondrial function and benefit PAH pat...

Coenzyme Q (CoQ, ubiquinone) is a component of the electron transport system in the mitochondria of eukaryotes and is essential for energy production. CoQ consists of a quinone moiety and an isoprenoid chain. Almost all living cells produce CoQ with different isoprenoid chain lengths. For example, CoQ10, which is a popular food supplement, possesses 10 isoprene units. CoQ10 is commercially prod...

We formalize the deenition and the metatheory of the Calculus of Constructions (CC) using the proof assistant Coq. In particular, we prove strong nor-malization and decidability of type inference. From the latter proof, we extract a certiied Objective Caml program which performs type inference in CC and use this code to build a small-scale certiied proof-checker.

The Coq proof assistant allows generation of programs correct by construction. This feature—called extraction—can be used to build certified libraries. In this article, we present a formalization of the extraction in Coq, along with some properties that have been formally proved. This work is in line with B. Barras’s work on formalizing Coq in Coq. MOTS-CLÉS : assistant de preuve, calcul des co...

Coenzyme Q (CoQ) is an essential factor for aerobic growth and oxidative phosphorylation in the electron transport system. The biosynthetic pathway for CoQ has been proposed mainly from biochemical and genetic analyses of Escherichia coli and Saccharomyces cerevisiae; however, the biosynthetic pathway in higher eukaryotes has been explored in only a limited number of studies. We previously repo...

In this article we show how we proved correctness of the translation from a small applicative language with recursive deenitions (Mini-ML) to the Categorical abstract machine (CAM) using the Coq system. Our aim was to mechanise the proof of J. Despeyroux 10]. Like her, we use natural semantics to axiomatise the semantics of our languages. The axiomatisations of inferences systems and of the lan...

The formation of a di-tert-alkyl nitroxide has been observed by Electron Spin Resonance during the exposure of coenzyme CoQ(10), in both the oxidized and reduced forms, to nitrogen dioxide (˙NO(2)) or to nitric oxide (˙NO) in the presence of oxygen. The same kind of nitroxide has been observed also with CoQ(1), CoQ(3) or with 1-phenyl-3-methyl-2-butene, chosen as model compounds. In all cases, ...

Previous studies showed that coenzyme Q(1) (CoQ(1)) reduction on passage through the rat pulmonary circulation was catalyzed by NAD(P)H:quinone oxidoreductase 1 (NQO1) and mitochondrial complex I, but that NQO1 genotype was not a factor in CoQ(1) reduction on passage through the mouse lung. The aim of the present study was to evaluate the complex I contribution to CoQ(1) reduction in the isolat...