[Integration of DNA oscillatory vector pSV neo to genome of NIH3T3: importance in investigations of transformation with c-Ha-ras oncogene].

Main aim of this study was evaluation of application of stable clones of transforming cells, containing DNA of plasmid vector for the investigation of oncogenes. Plasmid vector was constructed basing on pSV2neo vector, containing activated oncogene c-Ha-ras-1, derived from pT 24-C3 which was followed by evaluation of phenotypic and genetic changes in standard line of NIH3T3 mouse fibroblast line after transfection with constructed plasmid. After two weeks of culture in selective conditions, transformants resistant to geneticin were obtained and analysis of clones was performed after transfection with constructed vector containing ras oncogene and after transfection pSV2neo.

[Modulation of lymphocytes and immunoglobulins by serine proteinase of Staphylococcus aureus].

Serine proteinase of S. aureus binds with surface of peripheral blood lymphocytes and by proteolysis of polypeptides on the membrane and transduction of signals, changes in polyclonal activation of T and B lymphocytes occur. Cleavage of immunoglobulins tested in three classes and evaluated by electrophoresis in polyacrylamide gel (SDS-Page) of Ig fragments, was differing.

Instability of hybrid plasmids in Bacillus subtilis.

We studied the mechanisms responsible for instability of hybrid derivatives of staphylococcal R plasmids in B. subtilis cells. Four pBCH plasmids were constructed from staphylococcal chloramphenicol-resistance plasmid pC756 ligated with pBR322 or pUC8 vectors, and two pAEC plasmids contained pC756 plasmid, erm gene from S.