[Phase variation in Salmonella typhimurium phagetype].
The phase variation of phagetype was observed in cultures of Salmonella typhimurium collected from Xinjiang Uygur Autonomous Region during 1980-1993. A few cultures of phagetype 4774 or 4776(full type) may change into another phagetype, i.e. 4000(phase 1) or 0774 and 0776 (phase 2). In reverse, more strains of these phagetype 4000 and 0774(0776) easily back into their original phagetype 4774 or 4776. But some 4000(phase 1) can change to 0776(phase 2), and some 0774(phase 2) can also change to 4000(phase 1). Similarly, a few cultures of phagetype 7776(full type) can change to 7000(phase 1) or 0776(phase 2). More strains of these phagetype 7000(or 7002) and 0776 reverse easily to their original phagetype 7776 or 7774. The variability is 15.6% from full type to phase 1 or phase 2, and is 53.2% from phase 1 or phase 2 to full type. Understanding of phase variation of Salmonella typhimurium phagetype will be helpful to Salmonella phagetyping, and will be significance on epidemiological analysis of Salmonella infection.
He
X
X
Jiangxi Hygienic and Antiepidemic Station, Nanchang 330029.
Wang
L
L
Hu
X
X
Hou
H
H
Liu
M
M
D001434:Bacteriophage Typing; D014644:Genetic Variation; D012483:Salmonella Phages / Q000145:classification* / Q000235:genetics; D012486:Salmonella typhimurium / Q000821:virology*