The lysogenization of the non-O157 Escherichia coli strains by
stx-converting bacteriophage phi24B is associated with the O antigen
loss and reduced fitness
Golomidova A.K.a, Efimov A.D.a,
Kulikov E.E.a,b, Kuznetsov A.S.a,c ,
Letarov A.V.a,c*
aWinogradsky Institute of Microbiology RC
Biotechnology RAS, Moscow, Russia
bPhystech School of Biological and Medical Physics,
Moscow Institute of Physics and Technology, Moscow, Russia
cFaculty of Biology, Lomonosov Moscow State
University, Moscow, Russia
*Prospekt 60-letiya Oktyabrya 7 bld. 2., 117312,
Moscow, Russia. letarov@gmail.com
The lysogenization of the non-O157 Escherichia coli strains by
stx-converting bacteriophage phi24B is associated with the O antigen
loss and reduced fitness
Acquisition of new prophages that are able to increase the bacterial
fitness by lysogenic conversion is believed to be important strategy of
bacterial adaptation to changing environment. However, in contrast to
the factors determining the range of bacteriophage lytic activity,
little is known about the factors that define the lysogenization host
range. Bacteriophage phi24B is the paradigmal model of stx-converting
phages, encoding the toxins of the Shiga-toxigenic E. coli(STEC). This virus has been shown to lysogenize the wide range ofE. coli strains that is much broader than the range of the
strains supporting its lytic growth. Therefore, phages produced by the
STEC population colonizing the small intestine are potentially able to
lysogenize symbiotic E. coli in the hindgut, and these secondary
lysogens may contribute to the overall patient toxic load and to lead to
the emergence of new pathogenic STEC strains. We demonstrate, however,
that O antigen effectively limit the lysogenization of the wild E.
coli strains by phi24B phage. The lysogens are formed from the
spontaneous rough mutants and therefore have increased sensitivity to
other bacteriophages and to the bactericidal activity of the serum if
compared to their respective parental strains.
Keywords: stx-converting bacteriophages; shiga-toxigenic E. coli ;
LPS; O antigen; bacteriophage adsorption; temperate bacteriophages