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Updated: Aug 2, 2026
08:21
Site-specific Bacterial Chromosome Engineering: ΦC31 Integrase Mediated Cassette Exchange (IMCE)
Published on: March 16, 2012
The hidden life of integrative and conjugative elements
François Delavat1, Ryo Miyazaki2, Nicolas Carraro1
1Department of Fundamental Microbiology, University of Lausanne, 1015 Lausanne Switzerland.
FEMS Microbiology Reviews
|April 4, 2017
Summary
Integrative and conjugative elements (ICEs) utilize a bistable switch for transmission. A specialized subpopulation of cells facilitates ICE horizontal transfer, balancing host costs and ICE fitness.
Area of Science:
- Mobile genetic elements
- Microbial genetics
- Evolutionary biology
Background:
- Integrative and conjugative elements (ICEs) are mobile DNA elements capable of both vertical and horizontal transmission.
- Diverse ICE families exist with varying host ranges, regulatory networks, and gene content.
- Understanding the transmission dynamics and evolutionary strategies of ICEs is crucial.
Purpose of the Study:
- To propose a general model for the lifestyle of ICEs, explaining the transition between vertical and horizontal transmission.
- To elucidate the bistable decision-making process governing ICE transmission in host-microbe partnerships.
- To analyze the factors influencing the ratio of horizontal to vertical transmission.
Main Methods:
- Review of recent experimental data on ICE behavior.
- Development of a general model for ICE life cycle.
- Analysis of the balance between host fitness costs and ICE selection.
Main Results:
- ICE transmission is governed by a bistable switch, leading to host cell differentiation.
- A subpopulation of specialized cells initiates ICE horizontal transfer.
- The transmission ratio results from a balance between host fitness costs and ICE propagation.
Conclusions:
- ICEs exhibit a predominantly confined lifestyle but possess a dynamic horizontal transfer mechanism.
- Bistability allows ICEs to maintain integration while enabling efficient spread through dedicated cells.
- This model provides insights into the evolutionary adaptation and transmission strategies of mobile genetic elements.
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