Duplicated or Hybridized Peptide Functional Domains Promote Oral Homeostasis

Area of Science:

• Biochemistry and Molecular Biology
• Dental Research
• Materials Science

Background:

• Naturally occurring proteins often feature repeated functional domains for enhanced capacity.
• The enamel pellicle's statherin protein contains a DR9 domain with high hydroxyapatite affinity and protective qualities.
• Engineered peptides can leverage these domains for improved therapeutic outcomes.

Purpose of the Study:

• To test if multiplying functional domains in pellicle peptides amplifies protection against enamel demineralization.
• To evaluate the efficacy of engineered hybrid peptides incorporating statherin's DR9 domain and histatin 3's RR-14 sequence.
• To explore the potential of these peptides for therapeutic applications against dental caries, erosion, and oral candidiasis.

Main Methods:

• Enamel specimens were treated with single DR9, duplicated DR9 (DR9-DR9), hybrid DR9-RR14 peptides, native statherin, histatin 1, or distilled water.
• Specimens were subjected to a controlled demineralization process.
• Colorimetric assays measured calcium and phosphate release to quantify demineralization protection and antimicrobial activity against Candida albicans and Streptococcus mutans.

Main Results:

• DR9-DR9 significantly enhanced protection against enamel demineralization compared to single DR9 or statherin.
• The hybrid DR9-RR14 peptide demonstrated substantial protection against demineralization.
• DR9-RR14 retained significant antifungal activity against Candida albicans and killing activity against Streptococcus mutans.

Conclusions:

• Multiplication of functional domains in enamel pellicle peptides amplifies protection against demineralization.
• Engineered peptides like DR9-RR14 offer dual benefits of demineralization protection and antimicrobial properties.
• These findings support the development of stable, synthetic peptides for treating dental caries, erosion, and oral candidiasis.