Euglena gracilis Rhodoquinone:Ubiquinone Ratio and Mitochondrial Proteome Differ under Aerobic and

Euglena gracilis cells grown under aerobic and anaer-obic conditions were compared for their whole cell rhodoquinone and ubiquinone content and for major protein spots contained in isolated mitochondria as as-sayed by two-dimensional gel electrophoresis and mass spectrometry sequencing. Anaerobically grown cells had higher rhodoquinone levels than aerobically grown cells in agreement with earlier findings indicating the need for fumarate reductase activity in anaerobic wax ester fermentation in Euglena. Microsequencing re-vealed components of complex III and complex IV of the respiratory chain and the E1 subunit of pyruvate de-hydrogenase to be present in mitochondria of aerobi-cally grown cells but lacking in mitochondria from anaerobically grown cells. No proteins were identifie