Isogenic lysogens of diverse shiga toxin 2-encoding bacteriophages produce markedly different amounts of shiga toxin.
We produced isogenic Escherichia coli K-12 lysogens of seven different Shiga toxin 2 (Stx2)-encoding bacteriophages derived from clinical Shiga toxin-producing E. coli (STEC) isolates of serotypes O157:H7, O145, O111, and O83 to assess the variability among these phages and determine if there were phage-related differences in toxin production. Phage genomic restriction fragment length polymorphisms (RFLP) and superinfection resistance studies revealed significant differences among these phages and allowed the seven phages to be placed into five distinct groups. Experiments revealed striking differences in spontaneous phage and toxin production that were correlated with the groupings derived from the RFLP and resistance studies. These results suggest that the genotype of the Stx2 prophage can influence the level of phage release and toxin expression by host strains and thus may be relevant to STEC pathogenesis.
Wagner
P L
PL
Division of Geographic Medicine and Infectious Diseases, New England Medical Center and Tufts University School of Medicine, Boston, Massachusetts 02111, USA.
Acheson
D W
DW
Waldor
M K
MK
D001427:Bacterial Toxins / Q000096:biosynthesis* / Q000235:genetics; D003090:Coliphages / Q000235:genetics* / Q000502:physiology; D004279:DNA, Viral / Q000032:analysis / Q000235:genetics; D004926:Escherichia coli / Q000145:classification / Q000378:metabolism* / Q000821:virology*; D004927:Escherichia coli Infections / Q000382:microbiology; D019453:Escherichia coli O157 / Q000378:metabolism / Q000821:virology; D006801:Humans; D008242:Lysogeny; D012150:Polymorphism, Restriction Fragment Length; D022603:Shiga Toxins
D001427:Bacterial Toxins; D004279:DNA, Viral; D022603:Shiga Toxins