Disulfide Bonds: A Key Modification in Bacterial Extracytoplasmic Proteins
11 Department of Microbiology and Immunology, Dalhousie University, Halifax, NS, Canada.
Journal of Dental Research
|August 12, 2017
Summary
Oral bacteria utilize disulfide bonds, crucial for protein stability, impacting dental plaque formation and bacterial fitness. These bonds are formed by diverse thiol-disulfide oxidoreductases, essential for various bacterial processes.
Area of Science:
- Microbiology
- Biochemistry
- Oral Biology
Background:
- Disulfide bonds are vital posttranslational modifications for protein folding and stability in extracytoplasmic proteins across all domains of life.
- Enzymes catalyzing disulfide bond formation are crucial for numerous biological processes, ensuring protein function.
Purpose of the Study:
- To investigate the role and mechanisms of disulfide bond formation in oral bacteria.
- To understand the impact of disulfide bond formation on dental plaque-related phenotypes and bacterial fitness.
Main Methods:
- Review of existing literature and bioinformatic analysis of oral bacterial genomes.
- Identification of thiol-disulfide oxidoreductases and their conserved motifs (CXXC active site, C-terminal cis-proline).
Main Results:
- Gram-positive oral bacteria (e.g., Streptococcus gordonii, Actinomyces oris) use disulfide bonds for autolysis, biofilm formation, pilus assembly, and bacteriocin activity.
- Gram-negative oral bacteria (e.g., Porphyromonas gingivalis, Tannerella forsythia) employ disulfide bonds to stabilize outer membrane porins.
- Identified diverse thiol-disulfide oxidoreductases in oral bacteria, sharing key catalytic motifs.
Conclusions:
- Disulfide bond formation is a significant, emerging area in oral microbiology.
- This process critically influences dental plaque formation and the overall fitness of oral bacteria.
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