Genomic evolution and iron uptake in Pseudomonas aeruginosa.
Recombination and lateral transfer of genomic material has long been recognised as important to the evolution of pathogenic bacteria. However, few systematic studies of its effects have been undertaken. This study focussed on the contribution of recombination in genome evolution of the human pathogen P. aeruginosa. Analysis of ~500 sequenced genomes of P. aeruginosa showed that between 9 and 26% of genomic variation was introduced by DNA transferred in recombination events. These were not evenly distributed across the genome. Instead regions associated with interactions with the external environment and with host species were strongly overrepresented.
One of these genomic regions is responsible for synthesis of pyoverdine, an iron acquisition compound required for infection. Detailed analysis revealed that evolution of the pyoverdine locus is dependent on regulatory genes being transferred in different events and includes genes specific to the type of pyoverdine produced by each isolate. Molecular genetic manipulation demonstrated compatibility between regulatory genes from strains of P. aeruginosa that make different types of pyoverdine. Molecular pathways controlling pyoverdine production were then investigated to identify external factors that contribute to this process. Overall this research represents the first thorough analysis of recombination in the species P. aeruginosa and the implications this has on the evolution and regulation of a virulence locus.
|Date||Tuesday, 17 July 2018|
|Time||12:00pm - 1:00pm|
|Event Category||Health Sciences|
|Location||Biochemistry Seminar Room 231|