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Updated: Jul 5, 2026
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A Fluorescence-based Method to Study Bacterial Gene Regulation in Infected Tissues
Published on: February 19, 2019
The sigH gene sequence can subspeciate staphylococci
Kazuya Morikawa1, Ryosuke L Ohniwa, Miyuki Kumano
1Institute of Basic Medical Sciences, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba 305-8575, Japan. morikawa@sakura.cc.tsukuba.ac.jp
Diagnostic Microbiology and Infectious Disease
|May 20, 2008
Summary
The sigH gene, despite low homology, effectively differentiates staphylococcal species. This finding highlights sigH as a valuable tool for bacterial genotypic identification and species-level classification.
Area of Science:
- Microbiology
- Genetics
- Molecular Biology
Background:
- The sigH gene exhibits low sequence homology across staphylococcal species.
- Understanding staphylococcal diversity is crucial for clinical and epidemiological studies.
Purpose of the Study:
- To evaluate the utility of the sigH gene for differentiating staphylococcal species.
- To assess sigH as a molecular target for bacterial genotypic identification.
Main Methods:
- Analysis of "positionally cloned" sigH gene sequences from 39 staphylococcal species.
- Phylogenetic analysis of sigH sequences and comparison with 16S rRNA gene phylogeny.
Main Results:
- The phylogenetic tree topology derived from sigH sequences mirrored that of the 16S rRNA gene.
- sigH sequence data successfully differentiated certain clinical isolates at the species level.
- The sigH gene demonstrated high discriminative power among closely related staphylococcal species.
Conclusions:
- The sigH gene is a highly discriminative marker for differentiating staphylococcal species.
- sigH represents a promising molecular target for accurate genotypic identification in staphylococci.
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