Inheritance stability of hybrid plasmid TrS16 in transformant under long-term culture conditions without supporting selection

Abstract

Aim. The aim is to define the stability of inheritance the streptomycete recombinant plasmid TrS16 (8.4 kb) by TрS16 – 2 transformant cells of after the long-term storage without a purposeful selection (thiostrepton). Methods. Applied microbiological, genetic and physical-chemical methods. The recombinant plasmid of TrS16 was constructed on a base of the hybrid plasmid рАХ5а. The plasmidless variant of strain of Streptomyces globisporus 1912 was used as a recipient for the plasmid TrS16. Results. It is set that 5 % cells of transformant TрS16 – 2 population saved thiostrepton resistance after his periodic subculturings without selective pressure him during 5 years. The hybrid plasmid TrS16 was found only in a fourth from the investigated thiostreptonrecipient colonies of transformant of TрS16 – 2. Conclusions. The hybrid plasmid TrS16 is characterized satisfactory stability of inheritance by the transfotmant TрS16 – 2 after long-term storage of transformant without the use of thiostrepton for a purposeful selection.
 Keywords: plasmid, vector, insertion, stability of inheritance.