- Email: [email protected]
Synthesis of colicin A
Abstracts
sensitive strain was used as a control and compared to isogenic strains carrying mutations either in Btu B or in F genes . These studies , as well as other dealing with the killingeffect of Col A, demonstrated that the two proteins coded by Btu B and Om F genes from the outer membrane of E . cola cooperate to form tie recepto~ col A .
~~
SYNTHESIS OF COLICIN A Danièle CAVARD, Stanislas YARENNE , Alain BERNADAC and Claude LAZDUNSKI Centre de Biochimie et de Biologie Moléculaire du CNRS - BP 71, 13277 Marseille Cedex 9 . France
Colicins are antibiotic proteins produced by some strains of Enterocacteriacea which carry specific plasmids called colicinogenic factors . There is presently a wide interest in the mechanism and regulation of their production and export (1,2,3) . The synthesis of Colicins may be induced by mutagenic agents such as ultraviolet light or mitomycin C .
In the present work, synthesis of colicin A (Col A) was studied after induction with mitamycin C . Specific inhibition of chromosomal protein synthesis occured very shortly after mitamycin addition in wild type colicinogenic strains . There was not coordinate synthesis of Col A (61 000 Mr) and low molecular weight protein .Free and membrane-bound polysomes fractions were isolated fr~an cells induced with mitomycin C . These polysome fractions were used to program a cellfree system of protein synthesis . In this system, no reinitiation occured . Col A was synthesized in vitro in the free polysomes and not in the membrane-bound polysomes . The col~prnauced was localized by immunoferritin labelling on ultrathin section of frozen cells . It was exclusively detected in the cell cytoplasm . In the course of these studies , evidence was obtained that pauses or discontinuities occur during translation of the Col A mRNA .
(1) Jakes, K . and Model, P . (1979) J . Bacteriol . , 138 , 770-778 (2) Mock, M . and Schwartz, M . (1978) J . Bacteriol . ; 336, 700-707 . (3) Van Tiel-Menkveld, G .J ., Rezee, A . and de Graaf, F :K . (1979) J . Bacteriol ., 140, 415-423 .
255
sensitive strain was used as a control and compared to isogenic strains carrying mutations either in Btu B or in F genes . These studies , as well as other dealing with the killingeffect of Col A, demonstrated that the two proteins coded by Btu B and Om F genes from the outer membrane of E . cola cooperate to form tie recepto~ col A .
~~
SYNTHESIS OF COLICIN A Danièle CAVARD, Stanislas YARENNE , Alain BERNADAC and Claude LAZDUNSKI Centre de Biochimie et de Biologie Moléculaire du CNRS - BP 71, 13277 Marseille Cedex 9 . France
Colicins are antibiotic proteins produced by some strains of Enterocacteriacea which carry specific plasmids called colicinogenic factors . There is presently a wide interest in the mechanism and regulation of their production and export (1,2,3) . The synthesis of Colicins may be induced by mutagenic agents such as ultraviolet light or mitomycin C .
In the present work, synthesis of colicin A (Col A) was studied after induction with mitamycin C . Specific inhibition of chromosomal protein synthesis occured very shortly after mitamycin addition in wild type colicinogenic strains . There was not coordinate synthesis of Col A (61 000 Mr) and low molecular weight protein .Free and membrane-bound polysomes fractions were isolated fr~an cells induced with mitomycin C . These polysome fractions were used to program a cellfree system of protein synthesis . In this system, no reinitiation occured . Col A was synthesized in vitro in the free polysomes and not in the membrane-bound polysomes . The col~prnauced was localized by immunoferritin labelling on ultrathin section of frozen cells . It was exclusively detected in the cell cytoplasm . In the course of these studies , evidence was obtained that pauses or discontinuities occur during translation of the Col A mRNA .
(1) Jakes, K . and Model, P . (1979) J . Bacteriol . , 138 , 770-778 (2) Mock, M . and Schwartz, M . (1978) J . Bacteriol . ; 336, 700-707 . (3) Van Tiel-Menkveld, G .J ., Rezee, A . and de Graaf, F :K . (1979) J . Bacteriol ., 140, 415-423 .
255