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Conjugative Mating Assays for Sequence-specific Analysis of Transfer Proteins Involved in Bacterial Conjugation
10:41

Conjugative Mating Assays for Sequence-specific Analysis of Transfer Proteins Involved in Bacterial Conjugation

Published on: January 4, 2017

Description of a novel plasmid replicative origin from a genetically distinct family of conjugative plasmids

C A Viegas1, A K Lilley, K Bruce

  • 1Natural Environment Research Council, Institute of Virology and Environmental Microbiology, Oxford, UK.

FEMS Microbiology Letters
|April 1, 1997
PubMed

Insights

Researchers identified a novel replication origin (oriV) in a large mercury resistance plasmid. This origin initiates replication in Pseudomonas species, offering insights into plasmid maintenance in bacterial communities.

Area of Science:

  • Molecular Biology
  • Microbiology
  • Genetics

Background:

  • Conjugative plasmids play a crucial role in bacterial adaptation and evolution.
  • Understanding plasmid replication mechanisms is vital for controlling their persistence in microbial communities.
  • Mega-plasmids, like pQBR11, are significant genetic elements in pseudomonad populations.

Purpose of the Study:

  • To clone and sequence a novel replicative origin (oriV) from the mercury resistance plasmid pQBR11.
  • To investigate the functional role of this oriV in plasmid replication within Pseudomonas species.
  • To determine the characteristics of the oriV sequence and its replication mechanism.

Main Methods:

  • Cloning and sequencing of the oriV region from plasmid pQBR11.
  • Functional analysis using pUC-derived suicide vectors in Pseudomonas putida UWC1.
  • Sequence analysis to identify conserved motifs and regulatory elements.

Main Results:

  • A novel oriV was identified within a 300 bp unique sequence of pQBR11.
  • This oriV initiated replication of suicide vectors in Pseudomonas putida UWC1.
  • The oriV contained two directly repeated motifs, suggesting a single origin of replication.

Conclusions:

  • The identified oriV is functional and sufficient for initiating replication in Pseudomonas.
  • The oriV likely utilizes a host-polymerase dependent rolling circle mechanism for replication.
  • This finding contributes to understanding the persistence of large plasmids in bacterial communities.

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