Evidence for the occurrence of respiratory electron transport in adult Brugia pahangi and Dipetalonema viteae.

摘要: Abstract Mixed-sex adult stages of Brugia pahangi and Dipetalonema viteae, in the absence exogenous substrate, consumed oxygen at rates 4.18 ± 0.38 2.12 0.20 ngatoms O2 min−1 mg−1 dry wt. respectively. When calculated on a unit weight basis endogenous consumption (E-QO2) mature male macrofilariae B. D. viteae were significantly greater than those females, although E-QO2 per individual worm was essentially similar irrespective sex. assayed as separate unisexual groups, uptake female both species inhibited by classical inhibitors respiratory electron transport (RET), showed substrate bypass phenomena response to succinate ascorbate, N,N,N′,N′-tetramethyl-p-phenylenediamine with respect RET rotenone (inhibitor complex I) antimycin A III). Since worms elicited responses did mixed-sex and/or populations, possibility that developmental contained within filariids contributing any significant manner overall observed can be discounted. Such live-intact are normally only mitochondrial preparations suggest cuticles permeable rotenone, succinate, A, N,N,N′,N′-tetramethyl-p-phenylenediamine, azide cyanide. The uncoupler 2,4-dinitrophenol stimulated rate intact 33–160 μM, indicating probable occurrence RET-coupled oxidative phosphorylation. Higher concentrations proved inhibitory. Respiratory studies subcellular fractions substantiated parasites, suggesting presence A-sensitive -insensitive pathways capable utilising α-glycerophosphate, malate substrates. Both therefore probably possess branched RET-pathways bifurcating side RET-complex III. oxidation terms QO2 protein compare well other nematode parasites.