Naslov
RecBCD enzyme in UV-irradiated Escherichia coli interferes with site-specific and general recombination of lambda prophage

Autori
Vlahović, Ksenija ; Zahradka, Davor ; Petranović, Mirjana

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Kongres hrvatskih biokemičara i molekularnih biologa HB2000 - Knjiga sažetaka / Floegel, Mirna - Zagreb : Farmaceutsko-biokemijski fakultet Sveučilišta u Zagrebu, 2000, 69-69

Skup
HB2000 - Kongres hrvatskih biokemičara i molekularnih biologa

Mjesto i datum
Zagreb, Hrvatska, 13.10.2000. - 15.10.2000

Vrsta sudjelovanja
Poster

Vrsta recenzije
Domaća recenzija

Ključne riječi
Escherichia coli; lambda prophage; DNA recombination; recombinational DNA repair; RecBCD enzyme

Sažetak
RecBCD enzyme is involved in the radiation-induced process known as prophage inactivation. The process leads to the inability of lambda prophage to excise itself from the E. coli chromosome via site-specific recombination. In this work we wanted to further characterize the role of RecBCD enzyme in this process. In addition, we examined the ability of irradiated prophage to recombine with the infecting homologous phage. We used several E. coli mutants differentially altered in RecBCD's activities. The results showed that in the mutants carrying either recB2109 or recD1903, which do not exhibit significant nuclease activities, the prophage progressively loses its capacity for both site-specific and general recombination. In the recB268 null mutant, however, prophage recombinogenicity remained fully preserved. We also showed that the prophage unable to recombine retained its ability to complement the mutant infecting phage and that the recombination frequencies in phage x phage crosses were not affected by postirradiation incubation. Our results suggest that the helicase activity of RecBCD is responsible for the progressive loss of prophage recombinogenicity. This loss is most probably a consequence of the unsuccessful RecBCD-dependent recombinational repair of double-stranded breaks in the cell chromosome, during which some structures unsuitable for further recombination reactions may be produced.

Izvorni jezik
Engleski

Znanstvena područja
Biologija

POVEZANOST RADA