chapter  32
6 Pages

Entomology Sterility from CWD Streptococci

A new role for wall-deficient bacteria was discovered by Ehrman and coinvestigators (Figure 32-1 ) .7 CWD streptococci, residing peacefully in Drosophila, produce sterility in male offspring when subspecies of Drosophila are cross-mated. The streptococcal variants inhabit the testes, causing no disease in their original host unless large numbers of the CWD bacteria are injected into the insect, in which case sterility or loss of viability in offspring likewise may result as though from a cross­ match. Originally the symbionts were thought to be mycoplasma, shown untruc by electron micros­ copy and culture studies .