[Antimicrobial activity of carbon fiber fabric modified with a polymer-gentamicin complex].

Modified and unmodified carbon fiber supports were treated with solutions of a polymer-gentamicin complex, possessing high antimicrobial activity and low toxicity. It was found that the antimicrobial activity of modified carbon fiber fabrics depended on the nature of the support and on the immobilization conditions. The highest antimicrobial activity was observed with phosphorus-containing carbon fiber ion exchanger in salt form.

[Interactions of the phytopathogenic bacteria Erwinia with phage P1 CRL100 CML]. / Osobennosti vzaimodeistviia fitopatogennykh bakterii Errwinia s fagom P1 CRL100 CML.

The bacteriophage P1 Cm clr100 lysogenises the bacteria E. chrysanthemi, E. aroideae, E. atroseptica being localized in the cytoplasm, replicating but causing no cell lysis. The prophage induction results in transformation of the lysogenic bacteria E. chrysanthemi into nonviable filamentous cells. However, a portion of cells gets rid of the prophage and gives rise to normal heritage inheritors permitting to use the bacteriophage as an efficient vehicle for introducing the transposons into the chromosome of E. chrysanthemi. The transposon Tn9 has been found to insert into the different chromosomal sites causing no inactivation of the genes, while the transposition of Tn5 from the bacteriophage P1::Tn5Cmclr100 induces the different mutations with the frequency up to 3%. The bacteriophage P1Cmclr100 may also serve a tool for construction of the homology regions in the chromosome of E. chrysanthemi and Flac+ plasmid for further construction of Hfr-type donors.

[The role of te transposition of Tn1000 from Flac+-plasmid into chromosome of Erwinia chrysanthemi in the formation of Hfr-type donors]. / Rol' transpozitsii Tn1000 iz Flac+-plazmidy v khromosomu Erwinia chrysanthemi v formirovanii donorov Hfr-tipa.

Based on the data of stability of the donor state of Hfr-like strain Erwinia chrysanthemi VY1-10 in RecA+ and RecA- cells, it can be suggested that the donor properties of the strain are mediated by the presence of the genetic homology region which occurred as a result of transposition of the Tn1000 from the Flac+ plasmid into the chromosome of E. chrysanthemi. Tn1000 may be transposed into several sites on the chromosome of E. chrysanthemi ENA49. This leads to the appearance of donors transferring their chromosome from several fixed points oriT and in opposite directions. The location of these points and the direction of transfer are determined by Tn1000 insertion sites and their orientation.