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Horizontal gene transfer between bacteria

Published online by Cambridge University Press:  26 October 2007

Holger Heuer  and
Kornelia Smalla
Holger Heuer
Affiliation:
Federal Biological Research Centre for Agriculture and Forestry (BBA), Braunschweig, Germany
Kornelia Smalla
Affiliation:
Federal Biological Research Centre for Agriculture and Forestry (BBA), Braunschweig, Germany

Abstract

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Horizontal gene transfer (HGT) refers to the acquisition of foreign genes by organisms. The occurrence of HGT among bacteria in the environment is assumed to have implications in the risk assessment of genetically modified bacteria which are released into the environment. First, introduced genetic sequences from a genetically modified bacterium could be transferred to indigenous micro-organisms and alter their genome and subsequently their ecological niche. Second, the genetically modified bacterium released into the environment might capture mobile genetic elements (MGE) from indigenous micro-organisms which could extend its ecological potential. Thus, for a risk assessment it is important to understand the extent of HGT and genome plasticity of bacteria in the environment. This review summarizes the present state of knowledge on HGT between bacteria as a crucial mechanism contributing to bacterial adaptability and diversity. In view of the use of GM crops and microbes in agricultural settings, in this mini-review we focus particularly on the presence and role of MGE in soil and plant-associated bacteria and the factors affecting gene transfer.

Keywords

horizontal or lateral gene transfermobile genetic elementhorizontal gene poolgenome flexibility
Type
Research Article
Information
Environmental Biosafety Research , Volume 6 , Issue 1-2: Thematic Issue on Horizontal Gene Transfer , January 2007 , pp. 3 - 13
Copyright
© ISBR, EDP Sciences, 2007

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