MODIFICATION OF THE APOPTOTIC-LIKE EFFECTS OF MBP PROTEIN OVEREXPRESSION IN ESCHERICHIA-COLI BY FUSION WITH 14-3-3 DERIVED POLYPEPTIDES

Overexpression of even non-toxic proteins in bacteria causes a starvat ion-like response: the arrest of bacterial proliferation and apoptotic -like suicidal cell death. We have shown here that, as in the cells of higher organisms, these effects are accompanied by DNA degradation, T he fusion with the bacterial MBP of a polypeptide, belonging to the 14 -3-3 family and normally expressed in pumpkin (C. pepo), modifies the apoptotic-like effects of overexpression of this protein in E. coli. F usion of the full length 14-3-3 protein with the MBP considerably slow s down the DNA degradation caused by overexpression of the unmodified MBP. Overexpression of the construct containing a truncated version of the 14-3-3 polypeptide causes immediate arrest of bacterial growth an d rapid degradation of the chromosomal DNA. This result suggests that the DNA degradation in bacteria is an active process which can be modi fied to some extent by an endogenous protein.