Pathogenicity islands of virulent bacteria: structure, function and impact on microbial evolution

  title={Pathogenicity islands of virulent bacteria: structure, function and impact on microbial evolution},
  author={J{\"o}rg H Hacker and Gabriele Blum-Oehler and Inge Mühldorfer and Helmut Tschäpe},
  journal={Molecular Microbiology},
Virulence genes of pathogenic bacteria, which code for toxins, adhesins, invasins or other virulence factors, may be located on transmissible genetic elements such as transposons, plasmids or bacteriophages. In addition, such genes may be part of particular regions on the bacterial chromosome, termed‘pathogenicity islands’(Pais). Pathogenicity islands are found in Gram‐negative as well as in Gram‐positive bacteria. They are present in the genome of pathogenic strains of a given species but… 
Pathogenicity islands and the evolution of microbes.
Genomic islands are present in the majority of genomes of pathogenic as well as nonpathogenic bacteria and may encode accessory functions which have been previously spread among bacterial populations and are argued for the generation of pathogenicity islands by horizontal gene transfer.
Pathogenicity and other genomic islands in plant pathogenic bacteria.
A range of genomic islands in plant pathogenic bacteria including those that carry effector genes, phytotoxins and the type III protein secretion cluster are described including some medically important bacteria in order to discuss the range, acquisition and stabilization of genomic Islands.
[Plasticity of bacterial genomes: pathogenicity islands and the locus of enterocyte effacement (LEE)].
Many bacterial virulence attributes, like toxins, adhesins, invasins, iron uptake systems, are encoded within specific regions of the bacterial genome, which are termed pathogenicity islands (PAIs) since they confer pathogenic properties to the respective micro-organism.
Pathogenicity islands: a molecular toolbox for bacterial virulence
Data based on numerous sequenced bacterial genomes demonstrate that PAIs are present in a wide range of both Gram‐positive and Gram‐negative bacterial pathogens of humans, animals and plants.
Staphylococcus aureus mobile genetic elements
The mobile genetic elements of S. aureus namely bacteriophages, transposons, plasmids, and pathogenicity islands represent about 15 % Staphylococcus aureu genomes and contribute to the wide spread of microorganisms with an important effect on their genome plasticity and evolution.
Toxin genes on pathogenicity islands: impact for microbial evolution.
The Contribution of Pathogenicity Islands to the Evolution of Bacterial Pathogens
Genomic island (GEIs) represent formerly transferred or still mobile genetic entities that have evolved from horizontal gene transfer and DNA recombination events and will contribute to an ongoing evolution of bacterial variants, including bacterial pathogens.
Pathogenic diversity of Escherichia coli and the emergence of 'exotic' islands in the gene stream.
The contribution of intergenic inheritance to the adaptation and evolution of E. coli and other bacteria is presented and approaches to identify unique sequence islands (USIs), some of which might confer pathogenicity, are presented.
On the Role of Genomic Islands in Bacterial Pathogenicity and Antimicrobial Resistance
Genomic signature variation is utilized for detection of GEIs in host chromosome and Target DNAs are edited by Clustered regularly interspaced short palindromic repeats (CRISPRs) causing bacterial evolution and pathogenicity.


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    Zentralblatt fur Bakteriologie : international journal of medical microbiology
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Pathogenicity Islands: Bacterial Evolution in Quantum Leaps
Two pathogenicity islands in uropathogenic Escherichia coli J96: cosmid cloning and sample sequencing
It is proposed that such mobile genetic elements may have facilitated the spread of virulence determinants within PAI-specific sequences among bacteria.
Pathogenicity island evaluation in Escherichia coli K1 by crossing with laboratory strain K-12
Genomic DNA from the chimera failed to hybridize with sequences of the K1 capsule genes from strain RS218, suggesting that the chromosomal segment which was lost contained these sequences and indeed contained K1-specific virulence genes.
Adhesin regulatory genes within large, unstable DNA regions of pathogenic Escherichia coli: cross‐talk between different adhesin gene clusters
It is demonstrated that cross‐regulation of two unlinked virulence gene clusters together with the co‐ordinate loss of large DNA regions significantly influences the virulence of an extraintestinal E. coli wild‐type isolate.
tRNA genes and pathogenicity islands: influence on virulence and metabolic properties of uropathogenic Escherichia coli
It is demonstrated that the expression of other gene products influencing metabolic properties in addition to in vivo virulence are strongly dependent on the intact tRNA loci selC and leuX, and the results clearly show that the selenocysteine‐specific tRNA (tRNASec) directly influences the ability of the bacteria to grow under anaerobic conditions.
A role for bacteriophages in the evolution and transfer of bacterial virulence determinants
A virulence‐associated region in the genome of Dichelobacter nodosus has been shown to contain an integrase gene which is highly related to the integrases of Shigella flexneri phage Sf6 and
cag, a pathogenicity island of Helicobacter pylori, encodes type I-specific and disease-associated virulence factors.
The cag region may encode a novel H. pylori secretion system for the export of virulence determinants and Transposon inactivation of several of the cagI genes abolishes induction of IL-8 expression in gastric epithelial cell lines.
Identification of a virulence locus encoding a second type III secretion system in Salmonella typhimurium.
The newly identified SPI2 locus has a lower G+C content than that of the remainder of the Salmonella genome and is flanked by genes whose products share greater than 90% identity with those of the E. coli ydhE and pykF genes.
Virulence determinants of uropathogenic Escherichia coli and Proteus mirabilis.
It is concluded that the pathogenesis of urinary tract infection and acute pyelonephritis caused by uropathogenic E. coli and P. mirabilis are multifactorial, as mutation of single genes rarely causes significant attenuation of virulence.