The co-evolution of bacterial plant pathogens and their hosts is a complex and dynamic process. Host resistance imposes stress on invading pathogens that can lead to changes in the bacterial genome enabling the pathogen to escape host resistance. We have observed this phenomenon with the plant pathogen Pseudomonas syringae pv. phaseolicola where isolates that have lost the genomic island PPHGI-...

Mesorhizobium opportunistum strain WSM2075(T) was isolated in Western Australia in 2000 from root nodules of the pasture legume Biserrula pelecinus that had been inoculated with M. ciceri bv. biserrulae WSM1271. WSM2075(T) is an aerobic, motile, Gram negative, non-spore-forming rod that has gained the ability to nodulate B. pelecinus but is completely ineffective in N2 fixation with this host. ...

A 25,441-bp transposon was recovered from a Pseudomonas aeruginosa clinical isolate. While the transposition module was >99% identical to sequence of Tn1403, the element had been subject to rearrangements, with two In70.2-like class 1 integrons inserted into it in an unusual "tail-to-tail" configuration. One cassette array was the same as that in In70.2; however, the second was different, gener...

While the extent and impact of horizontal transfers in prokaryotes are widely acknowledged, their importance to the eukaryotic kingdom is unclear and thought by many to be anecdotal. Here we report multiple recent transfers of a huge genomic island between Penicillium spp. found in the food environment. Sequencing of the two leading filamentous fungi used in cheese making, P. roqueforti and P. ...

Here, we report the draft genome sequence of the Gram-negative strain Klebsiella pneumoniae RYC492, which produces the amyloid-forming and antibacterial peptide microcin E492. The sequenced genome consists of a 5,095,761-bp assembled open chromosome where the gene cluster for microcin production is located in a putative 31-kb genomic island flanked by sequence repeats and containing a putative ...

Difficulties in accurately identifying serovar 4,[5],12:i:- as monophasic variants of Salmonella enterica serovar Typhimurium mean there is confusion in the reporting of serovars Typhimurium and 4,[5],12:i:-. To gain insight into the prevalence and diversity of these monophasic variants in England and Wales, screening for fljB, hin and the serovar 4,[5],12:i:- DT193-associated genomic island wa...

Prochlorococcus ecotypes are a useful system for exploring the origin and function of diversity among closely related microbes. The genetic variability between phenotypically distinct strains that differ by less that 1% in 16S ribosomal RNA sequences occurs mostly in genomic islands. Island genes appear to have been acquired in part by phage-mediated lateral gene transfer, and some are differen...

Virulence factors of pathogenic bacteria (adhesins, toxins, invasins, protein secretion systems, iron uptake systems, and others) may be encoded by particular regions of the prokaryotic genome termed pathogenicity islands. Pathogenicity islands were first described in human pathogens of the species Escherichia coli, but have recently been found in the genomes of various pathogens of humans, ani...

BACKGROUND High levels of multidrug resistance are usually associated with mobile genetic elements that encode specific resistance genes. Integrons are important genetic elements involved in spreading antibiotic multi-resistance. In special cases, large exogenous segments in bacterial genomes form genomic islands, and one of the functions of these genomic islands is antibiotic resistance. Due t...

Genomic islands play a key role in prokaryotic genome plasticity. Genomic islands integrate into chromosomal loci such as transfer RNA genes and protein coding genes, whilst retaining various cargo genes that potentially bestow novel functions on the host organism. A gene encoding a putative integrase was identified at a single site within the 5' end of the dusA gene in the genomes of over 200 ...