Stage-specific Isoforms of Complex II (Succinate-Ubiquinone Oxidoreductase) in Mitochondria from the Parasitic Nematode, Ascaris suum

作者：Fumiko Saruta, Toshiaki Kuramochi, Kayako Nakamura, Shinzaburo Takamiya, Yong Yu, Takashi Aoki, Kazuhisa Sekimizu, Somei Kojima, Kiyoshi Kita · 发表于：Journal of Biological Chemistry · 年份：1995 · DOI：10.1074/jbc.270.2.928 · 被引用次数：69 · 研究领域：Helminth infection and control、Nematode management and characterization studies、Parasites and Host Interactions

Complex II from mitochondria of the adult parasitic nematode, Ascaris suum, exhibits high fumarate reductase activity and plays a key role in the anaerobic electron transport observed in these organelles. In contrast, mitochondria isolated from free living second stage larvae (L2) of A. suum show much lower fumarate reductase activity than those from adults, whereas succinate dehydrogenase activities of mitochondria in both stages are comparable. In the present study, biochemical and antigenic properties of the partially purified enzymes from both larval and adult mitochondria were compared. Larval complex II eluted from the DEAE-Cellulofine column chromatography at a lower salt concentration than adult enzyme, whereas the apparent molecular size of both enzyme complexes estimated by gel permeation column chromatography was the same. The fumarate reductase activity of larval complex II was less than 3% of that of adult enzyme, and the Km values for substrates were significantly different between the two complexes. The flavoprotein subunit of larval complex II could be distinguished from that of adult complex II by two-dimensional gel electrophoresis and peptide mapping. The antibody against the smallest subunit (small subunit of cytochrome b558) of the adult enzyme did not cross-react with that of the larval enzyme. These results suggest that larval complex II differs from adult enzyme and is more similar to aerobic mammalian enzymes with low fumarate reductase activity. This...