The endosymbionts of Glossina morsitans and G. palpalis: cultivation experiments and some physiological properties.

Pyruvate, malate, and succinate are the main substrates for bacteroid respiration; oxygen uptake can be inhibited by rotenone and antimycin A, but not by cyanide. The symbionts displayed limited growth and survival for over 80 days in a medium with succinate and pyruvate as main substrates, and supplemented with nucleotides. It was not possible to cultivate the endosymbionts of G. morsitans and G. palpalis intracellularly in cell cultures of the tsetse fly or of vertebrates. A high attraction between cells and symbionts was observed in these systems; about 10% of all bacteroids were incorporatedby the cells but they were lysed and digested within 48 h.