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Large-scale evolutionary analyses on SecB subunits of bacterial sec system
1State Key Laboratory of Non-food Biomass Enzyme Technology, National Engineering Research Center for Non-food Biorefinery, Guangxi Biomass Industrialization Engineering Institute, Guangxi Key Laboratory of Biorefinery, Guangxi Academy of Sciences, 98 Daling Road, Nanning, Guangxi, 530007, China.
Plos One
|March 17, 2015
Summary
This study analyzed 3,813 bacterial SecB protein sequences, revealing evolutionary patterns and functional conservation within the essential Sec secretion system. Findings highlight variances in SecB evolution across taxonomic groups, offering insights into bacterial protein transport mechanisms.
Area of Science:
- Microbiology
- Molecular Biology
- Evolutionary Biology
Background:
- Protein secretion systems are vital for bacterial cellular processes.
- The Sec system, crucial for protein translocation across the inner membrane, involves subunits like SecB.
- SecB's evolutionary history across diverse bacteria remained largely unexplored.
Purpose of the Study:
- To conduct a large-scale phylogenetic and statistical analysis of bacterial SecB sequences.
- To investigate the evolutionary relationships and functional conservation of SecB.
- To examine the variance of pairwise p-distances in SecB along taxonomic lineages.
Main Methods:
- Phylogenetic analysis of 3,813 bacterial SecB sequences.
- Statistical analysis of pairwise p-distances across taxonomic ranks (kingdom to organism).
- 3-D structure comparison of selected SecB proteins.
Main Results:
- Phylogenetic analysis elucidated SecB evolution and functional conservation.
- Significant variations in average pairwise p-distances were observed across taxonomic groups.
- Variance partitioning suggested contributions of vertical and horizontal gene transfer to SecB evolution.
Conclusions:
- SecB has evolved to maintain function across diverse bacterial taxa.
- Taxonomic lineage significantly impacts SecB sequence variance.
- Understanding SecB evolution provides insights into bacterial secretion and gene transfer mechanisms.
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