Ma. Preston et Aa. Borczyk, GENETIC-VARIABILITY AND MOLECULAR TYPING OF SHIGELLA-SONNEI STRAINS ISOLATED IN CANADA, Journal of clinical microbiology, 32(6), 1994, pp. 1427-1430
Restriction fragment length polymorphisms (RFLPs) of genomic DNAs from
49 clinical isolates of Shigella sonnei were analyzed by using a modi
fied restriction endonuclease analysis procedure to investigate the ge
netic variability of this species. After cleavage with the restriction
enzyme Haem or RsaI, DNA samples were electrophoresed in polyacrylami
de gels and the RFLP patterns were visualized by silver staining. The
results showed that among 20 strains associated with sporadic cases of
infection in three Canadian provinces, 15 distinct RFLP patterns were
revealed by HaeIII digestion and 12 distinct patterns were revealed b
y RsaI digestion. In contrast, the RFLP patterns of individual isolate
s within six groups of epidemiologically related isolates were identic
al to each other but distinct from those of unrelated isolates, and th
ese patterns could be used to determine the genetic relationships betw
een isolates associated with separate outbreaks of shigellosis. Our re
sults indicate that the modified restriction endonuclease analysis tec
hnique represents a rapid, reproducible, and highly discriminatory met
hod for the molecular typing of this species.