MicrobiologyOpen | |
Characterization of the genetic switch from phage ɸ13 important for Staphylococcus aureus colonization in humans | |
Camilla S. Kristensen1  Karin Hammer1  Mogens Kilstrup1  Anders K. Varming2  Leila Lo Leggio2  Helena A. K. Leinweber3  Hanne Ingmer3  | |
[1] Department of Biotechnology and Biomedicine Technical University of Denmark Lyngby Denmark;Department of Chemistry University of Copenhagen Kobenhavn Denmark;Department of Veterinary and Animal Sciences University of Copenhagen Kobenhavn Denmark; | |
关键词: bacteriophage; genetic switch; lysogeny; ɸ13; phi13; prophage; | |
DOI : 10.1002/mbo3.1245 | |
来源: DOAJ |
【 摘 要 】
Abstract Temperate phages are bacterial viruses that after infection either reside integrated into a bacterial genome as prophages forming lysogens or multiply in a lytic lifecycle. The decision between lifestyles is determined by a switch involving a phage‐encoded repressor, CI, and a promoter region from which lytic and lysogenic genes are divergently transcribed. Here, we investigate the switch of phage ɸ13 from the human pathogen Staphylococcus aureus. ɸ13 encodes several virulence factors and is prevalent in S. aureus strains colonizing humans. We show that the ɸ13 switch harbors a cI gene, a predicted mor (modulator of repression) gene, and three high‐affinity operator sites binding CI. To quantify the decision between lytic and lysogenic lifestyle, we introduced reporter plasmids that carry the 1.3 kb switch region from ɸ13 with the lytic promoter fused to lacZ into S. aureus and Bacillus subtilis. Analysis of β‐galactosidase expression indicated that decision frequency is independent of host factors. The white “lysogenic” phenotype, which relies on the expression of cI, could be switched to a stable blue “lytic” phenotype by DNA damaging agents. We have characterized lifestyle decisions of phage ɸ13, and our approach may be applied to other temperate phages encoding virulence factors in S. aureus.
【 授权许可】
Unknown