Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Comparison of H. pylori subclones

ABSTRACT: Helicobacter pylori has a very plastic genome, reflecting its high rate of recombination and point mutation. This plasticity promotes divergence of the population by the development of subclones and presumably enhances adaptation to host niches. We have investigated the genotypic and phenotypic characteristics of two such subclones isolated from one patient as well as the genetic evolution of these isolates during experimental infection. Whole-genome genotyping of the isolates using DNA microarrays revealed that they were more similar to each other than to a panel of other genotyped strains recovered from different hosts. Nonetheless, they still showed significant differences. The genomic evolution of both isolates during the infection of conventionally raised and germ-free mice was monitored over the course of 3 months. The Cag PAI-positive isolate was also surveyed after a 10 month colonization of conventionally raised transgenic animals (n = 9 mice). Microarray analysis of the Cag PAI and sequence analysis of the cagA, recA, and 16S rRNA genes disclosed no changes in recovered isolates. Together, these results reveal that the H. pylori population infecting one individual can undergo significant divergence, creating stable subclones with substantial genotypic and phenotypic differences. Set of arrays organized by shared biological context, such as organism, tumors types, processes, etc. Computed

ORGANISM(S): Helicobacter pylori

SUBMITTER: Nina Salama

PROVIDER: E-GEOD-3478 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Publications

Comparison of genetic divergence and fitness between two subclones of Helicobacter pylori.

Björkholm B B Lundin A A Sillén A A Guillemin K K Salama N N Rubio C C Gordon J I JI Falk P P Engstrand L L

Infection and immunity 20011201 12

Helicobacter pylori has a very plastic genome, reflecting its high rate of recombination and point mutation. This plasticity promotes divergence of the population by the development of subclones and presumably enhances adaptation to host niches. We have investigated the genotypic and phenotypic characteristics of two such subclones isolated from one patient as well as the genetic evolution of these isolates during experimental infection. Whole-genome genotyping of the isolates using DNA microarr ...[more]

PMID: 11705965

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Dataset Information

Comparison of H. pylori subclones

Publications

Comparison of genetic divergence and fitness between two subclones of Helicobacter pylori.

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