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Biochemical and Structural Characterization of the Carbohydrate Transport Substrate-binding-protein SP0092
Published on: October 2, 2017
Structural and antigenic characteristics of Streptococcus sobrinus glucan binding proteins
1Department of Immunology, Forsyth Dental Center, Boston, Massachusetts 02115, USA. dsmith@forsyth.org
Infection and Immunity
|October 24, 1998
Summary
Glucan binding proteins (GBPs) from Streptococcus sobrinus were analyzed. GBP-3 and GBP-5 are similar, but distinct from GBP-2, suggesting different functions in oral bacteria.
Area of Science:
- Microbiology
- Protein Chemistry
- Immunology
Background:
- Glucan binding proteins (GBPs) are crucial for Streptococcus species adhesion and biofilm formation.
- Understanding the structural and antigenic properties of GBPs is essential for developing targeted interventions against oral pathogens.
Purpose of the Study:
- To structurally and antigenically compare three purified glucan binding proteins (GBP-2, GBP-3, and GBP-5) from Streptococcus sobrinus 6715.
- To investigate the relationship between S. sobrinus GBPs and those from Streptococcus mutans.
Main Methods:
- Mass spectroscopy of tryptic fragments for structural analysis.
- Western blot analysis using rat antisera for antigenic comparison.
- Comparison with peptides containing putative glucan binding epitopes.
Main Results:
- GBP-3 and GBP-5 exhibited high structural and antigenic similarity.
- GBP-2 was antigenically distinct from both GBP-3 and GBP-5.
- No significant antigenic relationship was observed between S. sobrinus GBPs and GBPs from Streptococcus mutans.
Conclusions:
- S. sobrinus GBP-2 and GBP-3 represent distinct proteins, likely with different functional roles.
- S. sobrinus GBP-5 may be a degradation product of GBP-3 or arise from closely related genes.
- These findings contribute to understanding the diversity of GBPs in oral streptococci.
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