- Autor(in)
- Seitenbereich
-
061 - 073
- Zusammenfsg.
-
In order to compare the oxidative metabolism of a symbiotic strain (SS) and an aposymbiotic strain (AA) of Sitophilus oryzae, we isolated mitochondria from adult insects and subjected them to oxygraph measurements to determine the respiratory control ratio (RCR) and the ADP/O ratios. The RCR was very high in both strains but significantly higher in the symbiotic strain. Respiration was accompanied by phosphorylation of ADP, and ADP/O values were not significantly different in the SS and AA strains (t-test, p = 0.05). We conclude that a modification of the aposymbiotic strain has occurred at the level of respiratory control and after the elimination of the symbiotic bacteria. These bacteria lacked oxidative metabolism. When they were incubated in the oxygraph under the same conditions as mitochondria, they display no oxygen uptake. The symbiotic bacteria not only interacted with the cytoplasmic metabolism, but also with the mitochondrion metabolism.