[Prophage CTXphi genome variability and its role in alteration of Vibrio cholerae El Tor virulence characteristics].
Comparative analysis of CTXphi prophage genome of 366 V. cholerae El Tor strains isolated from infected people and water was carried out using the polymerase chain reaction. Four groups of vibrios, which carry different combinations of ctxA, zot, and ace genes from core region of CTXphi prophage coding key (cholera enterotoxin) and accessory (Zot and Ace toxins) pathogenicity factors, were determined: ctxA(+) zot(-) ace(+), ctxA(-) zot(+) ace(+), ctxA(-) zot(+) ace(-), ctxA(-) zot(-) ace(+). Vibrios that had lost all tested genes were also revealed. Genomic rearrangements occurring in water environment in virulent V. cholerae strains, which acquired foreign pathogenicity genes necessary for their existence in human organism, were proposed as one of the mechanisms of formation of clones with an incomplete or no prophage. Infection process in model animals challenged with wild and isogenic strains of V. cholerae differing in the set of the phage genes (ctxA, zot, and ace) was comparatively analyzed. It was shown that variability of CTXphi prophage genome was an important factor of modification of cholera vibrios virulent characteristics. Obtained data point to usefulness of ctxA, zot, and ace phage genes detection in wild V. cholerae isolates as it could permit evaluation of their virulent potential determining the severity of the infection.
Smirnova
N I
NI
Osin
A V
AV
Nefedov
K S
KS
Kul'shan'
T A
TA
Zadnova
S P
SP
Livanova
L F
LF
Toporkov
A V
AV
Kutyrev
V V
VV
D000818:Animals; D001435:Bacteriophages / Q000235:genetics*; D002771:Cholera / Q000382:microbiology*; D002772:Cholera Toxin / Q000235:genetics; D004731:Endotoxins; D014644:Genetic Variation; D016679:Genome, Viral; D044404:Genomic Islands / Q000235:genetics; D006801:Humans; D016133:Polymerase Chain Reaction; D039002:Prophages / Q000235:genetics*; D011817:Rabbits; D041241:Vibrio cholerae O1 / Q000235:genetics / Q000472:pathogenicity / Q000821:virology*; D014758:Viral Core Proteins / Q000235:genetics; D014774:Virulence; D014871:Water Microbiology
C081530:Ace toxin; D004731:Endotoxins; D014758:Viral Core Proteins; C077728:zonula occludens toxin, Vibrio cholerae; D002772:Cholera Toxin