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Updated: Aug 9, 2026
11:10
High-throughput Assay to Phenotype Salmonella enterica Typhimurium Association, Invasion, and Replication in Macrophages
Published on: August 12, 2014
[Phase variation in Salmonella typhimurium phagetype]
Wei Sheng Wu Xue Bao = Acta Microbiologica Sinica
|January 31, 2003
Summary
Salmonella typhimurium phagetypes exhibit phase variation, with a 15.6% rate of change from full to phase types and a 53.2% rate of change back to full types. This variation impacts Salmonella phagetyping and epidemiological analysis.
Area of Science:
- Microbiology
- Bacteriology
Context:
- Salmonella typhimurium strains collected in Xinjiang Uygur Autonomous Region between 1980-1993 displayed significant phase variation.
- Observed variations involved shifts between specific full phagetypes (e.g., 4774, 4776, 7776) and their phase 1 (e.g., 4000, 7000) or phase 2 (e.g., 0774, 0776) forms.
Purpose:
- To document and analyze the phase variation patterns in Salmonella typhimurium phagetypes.
- To investigate the reversibility and directionality of these phagetype changes.
Summary:
- Phase variation was observed in Salmonella typhimurium, with 'full type' phagetypes occasionally converting to 'phase 1' or 'phase 2' types (15.6% variability).
- Conversely, a higher rate (53.2% variability) was noted for phase types reverting to their original full types.
- Interconversion between different phase types (e.g., phase 1 to phase 2) was also documented.
Impact:
- Understanding Salmonella typhimurium phase variation is crucial for accurate Salmonella phagetyping.
- These findings have significance for the epidemiological analysis of Salmonella infections, aiding in tracking and understanding transmission dynamics.
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