title: [Use of ultrasound to obtain small Escherichia coli cells containing drd plasmids].
abstract: Treatment with ultrasound of Escherichia coli K-12 chi 1100 producing mini-cells and containing R factor 100-1 drd depressed in conjugation transfer, prior to defferential and zonal centrifugation, makes it possible to increase the yield and purity of mini-cells. Combination of ultrasound treatment with differential centrifugation produces mini-cells with purity greater than 10(3) per parent cell. Ultrasound has no negative effect on the physiological state of mini-cells and the hydrodynamical characteristics of segregated plasmid DNA.
mesh_terms: D004926:Escherichia coli / Q000166:cytology; D014465:Ultrasonics
vernacular_title: Primenenie ul'trazvuka dlia polucheniia nelikikh kletok Escherichia coli, soderzhashchikh drd plazmidy.