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Transposition of IS10R in Lactococcus lactis
1Laboratory of Microbial Gene Technology and Food Microbiology, Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, As, Norway.
Journal of Applied Microbiology
|January 6, 2009
Summary
The IS10R insertion element transposes in Lactococcus lactis, a key bacterium in food production. This transposition, dependent on the nisR gene, disrupts genes at a specific DNA sequence, offering potential for gene editing applications.
Area of Science:
- Microbiology
- Bacteriology
- Molecular Biology
Background:
- The IS10R insertion element's role in gene disruption was previously unknown in Lactococcus lactis.
- Lactococcus lactis is an industrially significant bacterium used in food fermentation.
Purpose of the Study:
- To investigate the transposition mechanism of the IS10R element.
- To understand how IS10R mediates gene disruption in Lactococcus lactis.
Main Methods:
- Polymerase Chain Reaction (PCR) and DNA sequencing were used to analyze gene disruption.
- Site-directed mutagenesis identified the target integration site of IS10R.
- Co-expression studies with the nisR gene investigated its role in transposition.
Main Results:
- The IS10R element disrupted the flciA gene in L. lactis NZ9000, leading to loss of lactococcin A immunity.
- Transposition was dependent on the presence of the nisR regulator gene.
- The specific DNA sequence 5'-CACTTAACC-3' was identified as the target site for IS10R integration.
Conclusions:
- IS10R transposition in L. lactis NZ9000 is regulated by the nisR gene.
- IS10R utilizes the 5'-CACTTAACC-3' sequence as its integration site.
- IS10R presents a controllable system for gene disruption in L. lactis, with potential applications in genetic engineering.
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