ALOX12 in human toxoplasmosis.

ALOX12 is a gene encoding arachidonate 12-lipoxygenase (12-LOX), a member of a nonheme lipoxygenase family of dioxygenases. ALOX12 catalyzes the addition of oxygen to arachidonic acid, producing 12-hydroperoxyeicosatetraenoic acid (12-HPETE), which can be reduced to the eicosanoid 12-HETE (12-hydroxyeicosatetraenoic acid). 12-HETE acts in diverse cellular processes, including catecholamine synthesis, vasoconstriction, neuronal function, and inflammation.

Inhibition of p-aminobenzoate and folate syntheses in plants and apicomplexan parasites by natural product rubreserine.

Glutamine amidotransferase/aminodeoxychorismate synthase (GAT-ADCS) is a bifunctional enzyme involved in the synthesis of p-aminobenzoate, a central component part of folate cofactors. GAT-ADCS is found in eukaryotic organisms autonomous for folate biosynthesis, such as plants or parasites of the phylum Apicomplexa. Based on an automated screening to search for new inhibitors of folate biosynthesis, we found that rubreserine was able to inhibit the glutamine amidotransferase activity of the plant GAT-ADCS with an apparent IC(50) of about 8 μM.

NALP1 influences susceptibility to human congenital toxoplasmosis, proinflammatory cytokine response, and fate of Toxoplasma gondii-infected monocytic cells.

NALP1 is a member of the NOD-like receptor (NLR) family of proteins that form inflammasomes. Upon cellular infection or stress, inflammasomes are activated, triggering maturation of proinflammatory cytokines and downstream cellular signaling mediated through the MyD88 adaptor. Toxoplasma gondii is an obligate intracellular parasite that stimulates production of high levels of proinflammatory cytokines that are important in innate immunity.

The rat Toxo1 locus directs toxoplasmosis outcome and controls parasite proliferation and spreading by macrophage-dependent mechanisms.

Toxoplasmosis is a healthcare problem in pregnant women and immunocompromised patients. Like humans, rats usually develop a subclinical chronic infection. LEW rats exhibit total resistance to Toxoplasma gondii infection, which is expressed in a dominant mode.

Toxoplasma gondii acyl-lipid metabolism: de novo synthesis from apicoplast-generated fatty acids versus scavenging of host cell precursors.

Toxoplasma gondii is an obligate intracellular parasite that contains a relic plastid, called the apicoplast, deriving from a secondary endosymbiosis with an ancestral alga. Metabolic labelling experiments using [14C]acetate led to a substantial production of numerous glycero- and sphingo-lipid classes in extracellular tachyzoites. Syntheses of all these lipids were affected by the herbicide haloxyfop, demonstrating that their de novo syntheses necessarily required a functional apicoplast fatty acid synthase II.

The Arabidopsis nuclear DAL gene encodes a chloroplast protein which is required for the maturation of the plastid ribosomal RNAs and is essential for chloroplast differentiation.

Altered pigmentation is an easily scored and sensitive monitor of plastid function. We analyzed in detail a yellow colored transposon-tagged mutant (dal1-2) that is allelic to the dal mutant previously identified (Babiychuk et al., 1997).