An unusual helix-turn-helix protease inhibitory motif in a novel trypsin inhibitor from seeds of Veronica (Veronica hederifolia L.).

The storage tissues of many plants contain protease inhibitors that are believed to play an important role in defending the plant from invasion by pests and pathogens. These proteinaceous inhibitor molecules belong to a number of structurally distinct families. We describe here the isolation, purification, initial inhibitory properties, and three-dimensional structure of a novel trypsin inhibitor from seeds of Veronica hederifolia (VhTI).

Structure of lactate dehydrogenase from Plasmodium vivax: complexes with NADH and APADH.

Malaria caused by Plasmodium vivax is a major cause of global morbidity and, in rare cases, mortality. Lactate dehydrogenase is an essential Plasmodium protein and, therefore, a potential antimalarial drug target. Ideally, drugs directed against this target would be effective against both major species of Plasmodium, P.

Fungal respiration: a fusion of standard and alternative components.

In animals, electron transfer from NADH to molecular oxygen proceeds via large respiratory complexes in a linear respiratory chain. In contrast, most fungi utilise branched respiratory chains. These consist of alternative NADH dehydrogenases, which catalyse rotenone insensitive oxidation of matrix NADH or enable cytoplasmic NADH to be used directly.

New sequence data enable modelling of the fungal alternative oxidase and explain an absence of regulation by pyruvate.

Respiratory rates involving the alternative oxidase (AO) were studied in mitochondria from Tapesia acuformis. There was no evidence for regulation by pyruvate, in contrast with plant AO. The site of interaction of pyruvate with the plant AO is a conserved cysteine.

Characterization of a split respiratory pathway in the wheat "take-all" fungus, Gaeumannomyces graminis var. tritici.

This article describes the first detailed analysis of mitochondrial electron transfer and oxidative phosphorylation in the pathogenic filamentous fungus, Gaeumannomyces graminis var. tritici. While oxygen consumption was cyanide insensitive, inhibition occurred following treatment with complex III inhibitors and the alternative oxidase inhibitor, salicylhydroxamic acid (SHAM).