Title:The Application of a Recombinant Antimicrobial Peptide of
Thrombocidin-1 Expressed in Pichia pastoris as a Novel Approach Against
Some Oral Pathogenic Bacteria: An In Vitro Study
Volume: 29
Issue: 1
Author(s): Fatemeh Forouzanfar, Hamideh Sadat Mohammadipour, Majid Akbari, Reza Beyraghshamshir, Abbas Tanhaeian and Elnaz Karimian*
Affiliation:
- Department of Cosmetic and
Restorative Dentistry, Dental School, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
Keywords:
Antimicrobial peptide, E. faecalis, Streptococus mutans, Thrombocidin-1, cytotoxicity, antibacterial.
Abstract: Objective: Oral infections and dental caries are considered serious health problems.
Therefore, searching for new agents with antimicrobial properties seems to be crucial. This study
aimed to evaluate the antimicrobial activity of the recombinant Thrombocidin-1 [TC-1] peptide on
some oral pathogens. Also, the cytotoxicity of this peptide on human gingival fibroblast cells was
investigated.
Methods: In this study, Pichia pastoris was used for the expression of recombinant TC-1. The microbroth
dilution method was used to determine the minimum inhibitory concentration [MIC] and
minimum bacterial concentration [MBC]. It tested against four main oral pathogens; Streptococcus
mutans, Streptococcus salivarius, Streptococcus oralis, and Enterococcus faecalis. Moreover, the
cytotoxicity analysis was done on gingival fibroblast cells by the MTT method. The data were analyzed
using a two-way analysis of variance [ANOVA] and Tukey’s HSD tests.
Results: The most bactericidal effect of TC-1 was against S. salivarius, the highest bacteriostatic effect
was against S. salivarius, and S. oralis had the lowest MIC value of 1.512 μg/ml. The Thrombocidin-
1 peptide showed lower antibacterial properties against E. faecalis compared with CHX,
unlike the stronger antimicrobial effect on examined streptococci. According to cytotoxicity examination,
no concentration of TC-1 presented over 50% growth inhibition [IC50] of the fibroblasts
cells.
Conclusion: Based on antimicrobial tests and cytotoxicity results, the Thrombocidin-1 peptide
may be useful as a safe antibacterial agent against some oral pathogens in dental materials.