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Phenotypic variability of beta-glucoside utilization and its correlation to pathogenesis process in a few enteric
1Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore, India. aru@teacher.com
FEMS Microbiology Letters
|May 30, 2001
Summary
Enterobacteriaceae members show variable beta-glucoside utilization due to gene deletions. Shigella sonnei retains complete bgl and cel operons, unlike Salmonella and other species, explaining phenotypic differences.
Area of Science:
- Microbiology
- Genomics
- Evolutionary Biology
Background:
- Beta-glucoside utilization varies significantly across Enterobacteriaceae.
- Understanding the genetic basis of this variability is crucial for evolutionary insights.
Purpose of the Study:
- To investigate the molecular basis for differential beta-glucoside utilization in Enterobacteriaceae.
- To identify genetic homologs of beta-glucoside (bgl) and cellobiose (cel) operons in key species.
Main Methods:
- Genomic hybridization was employed using Escherichia coli bgl and cel genes as probes.
- Comparative analysis of gene presence and deletions across selected bacterial species.
Main Results:
- Shigella sonnei possesses complete homologs of both bgl and cel operons.
- Salmonella, Proteus mirabilis, Enterobacter aerogenes, and Pseudomonas aeruginosa exhibit deletions in bglF and bglB genes, retaining only bglR and bglG homologs.
- Cel operon homologs were found in S. sonnei and Salmonella.
Conclusions:
- Gene deletions in bgl operons explain the observed phenotypic variability in beta-glucoside utilization.
- Evolutionary events have led to distinct genetic architectures for beta-glucoside metabolism in Enterobacteriaceae.
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