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Methods for Electroporation and Transformation Confirmation in Limosilactobacillus reuteri DSM20016
Published on: June 23, 2023
Functional genomics of probiotic Lactobacilli.
Todd R Klaenhammer1, Eric Altermann, Erika Pfeiler
1Department of Food, Bioprocessing, and Nutrition Sciences, North Carolina State University, Raleigh, NC 27695, USA. Klaenhammer@ncsu.edu
Journal of Clinical Gastroenterology
|August 8, 2008
Summary
Probiotic lactic acid bacteria (LAB) genomes reveal unique strain-specific genes. Comparative genomics identified Lactobacillus-specific genes for adhesion and nutrient transport, crucial for probiotic functions.
Area of Science:
- Microbiology
- Genomics
- Probiotics
Background:
- Lactic acid bacteria (LAB) have a long history in fermentation and are increasingly used as probiotics.
- Significant genotypic and phenotypic variations exist among LAB strains, necessitating strain-specific analysis.
- The number of publicly available probiotic LAB genomes has grown substantially since 2002.
Purpose of the Study:
- To analyze published probiotic LAB genomes and identify genetic traits linked to probiotic functions.
- To conduct a comparative genomic analysis of Lactobacillus strains against other LAB.
- To identify strain-specific and group-specific genes within Lactobacillus.
Main Methods:
- Comparative genomic analysis of 4 sequenced Lactobacillus strains against 25 public LAB genomes.
- Differential Blast Analysis to compare each genome with related Lactobacillus and other LAB genomes.
- Whole genome transcriptional profiling of Lactobacillus acidophilus and its mutants under various conditions.
Main Results:
- Identified strain-specific genes not found in other LAB, including mucus-binding proteins for adhesion.
- Discovered group-specific genes shared within Lactobacillus, such as carbohydrate and amino acid transport systems.
- Highlighted gene targets in L. acidophilus for functional studies, including adhesion, acid/bile tolerance, and quorum sensing.
Conclusions:
- Comparative genomics is effective in uncovering unique genetic features of probiotic LAB.
- Lactobacillus-specific genes identified are critical for probiotic mechanisms like adhesion and nutrient utilization.
- Functional analysis of identified gene targets in L. acidophilus can elucidate probiotic efficacy.
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