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Genetic context and structural diversity of class 1 integrons from human commensal bacteria in a hospital intensive care unit.

ABSTRACT: Most surveys for class 1 integrons are at least partly predicated on PCR screening that targets integron conserved regions. However, class 1 integrons are structurally diverse, so dependence on conserved regions may lead to missing clinically relevant examples of class 1 integrons. Here, we surveyed a commensal population of bacteria from patients in an intensive care unit to identify class 1 integrons irrespective of their structure or genetic context. We identified several examples of class 1 integrons linked to complete Tn402-like or Tn402 hybrid transposition modules and diverse insertion points with respect to the inverted repeat IRi boundary. The diversity and abundance of class 1 integrons identified are such that many novel elements seen here would not have been identified by commonly used methods, and they revealed an additional level of complexity.

SUBMITTER: Betteridge T

PROVIDER: S-EPMC3147655 | biostudies-literature | 2011 Aug

REPOSITORIES: biostudies-literature

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Genetic context and structural diversity of class 1 integrons from human commensal bacteria in a hospital intensive care unit.

Betteridge Thu T Partridge Sally R SR Iredell Jonathan R JR Stokes H W HW

Antimicrobial agents and chemotherapy 20110531 8

Most surveys for class 1 integrons are at least partly predicated on PCR screening that targets integron conserved regions. However, class 1 integrons are structurally diverse, so dependence on conserved regions may lead to missing clinically relevant examples of class 1 integrons. Here, we surveyed a commensal population of bacteria from patients in an intensive care unit to identify class 1 integrons irrespective of their structure or genetic context. We identified several examples of class 1 ...[more]

PMID: 21628540

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