Spontaneous switching of the sucrose-promoted colony phenotype in Streptococcus sanguis.
نویسندگان
چکیده
Streptococcus sanguis on media containing 3% sucrose gives rise to characteristic hard cohesive colonies (designated Spp+). Populations of Spp+ bacteria (strain Challis) on sucrose media switch to a soft noncohesive phenotype (designated Spp-) at a frequency of 10(-4) to 10(-3). Spp- bacteria switch back to Spp+ bacteria at a similar frequency. Successive rounds of Spp variation were observed. The Spp phenotypic switch was associated with changes in extracellular glucosyltransferase activity.
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ورودعنوان ژورنال:
- Infection and immunity
دوره 57 12 شماره
صفحات -
تاریخ انتشار 1989