[Genoprotective effect of drugs based on ecdysteroids in poisoning of rats with tetrachloromethane and chlorophos].

Molecular mechanisms of chromatin damage have been investigated during tetrachloromethane and chlorophos intoxication of experimental animals. Introduction of tetrachloromethane to experimental animals induced chromatin degradation causing a partial loss of histone H1-DNA fragmentation and formation of intermolecular bonds: DNA-protein. Intoxication with chlorophos results in repression of a part of genes due to augmented chromatin compactness.

[The use of the multicopy plasmid pUC19 for assuring the constitutive expression of gene rplL in Escherichia coli].

A mutation in lac-operator region of pUC19 plasmid causing an increase in beta-galactosidase activity was observed. The plasmid was used as a vector to provide high level of expression of the cloned E. coli rplL gene.