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Effect of Quorum-sensing Molecules on Early Stage of Candida Albicans Biofilms Formation

Author: Pan
Tutor: LiuWeiHong；WeiZuo
School: Nanjing Medical University
Course: Clinical Stomatology
Keywords: Candida albicans Biofilm Quorum sensing molecules tyrosol farnesol HTA1 EFG1
CLC: R379
Type: Master's thesis
Year: 2008
Downloads: 187
Quote: 0
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Abstract

Candida albicans (Candida albicans) are common conditions within the human oral pathogenic fungi, biofilm Oral Candida albicans is the most common way of life is important in clinical infections. In recent years, many scholars have found that quorum sensing and Candida albicans biofilm formation and its stability remain closely related to. farnesol (farnesol) and tyrosol (p-hydroxyphenyl ethanol) is now known to Candida albicans unique two quorum sensing molecules, more in-depth study of the former and less the latter's role in research. In this study, an inverted microscope and RT-PCR technique was used to observe the two quorum sensing molecules on the early Candida albicans biofilms (90 min) cell morphology and HTA1 and the EFG1 gene expression regulation by MTT assay of quorum sensing molecules on white rosary the bacteria the early biofilm cell proliferation quantitative analysis, tyrosol and farnesol in-depth study of the mechanism of action to provide a theoretical basis. The role of the first part of the quorum sensing molecules early Candida albicans biofilm morphology [Materials and Methods] mouthwash method for Candida albicans clinical isolates, RPMI 1640 medium preparation concentration of 1.0 × 10 ^{6 / mL strains and clinical isolates of Candida albicans standard standard bacterial suspension, 5% CO ₂ 37 ° C under the conditions of 50 mL flasks as vector construction early Candida albicans biofilm model. Plant Candida albicans in biofilm growth process, depending on the effect of quorum sensing molecules of three groups treated and control groups: (1): 100μM tyrosol (tyrosol group); (2): 50 μm famesol (farnesol group ); (3): 50μM the farnesol 500μM Tyrosol (the mixing treatment group); (4): None of quorum sensing molecules (control group). Candida incubated for 90 min to form the white of the early biofilm morphology was observed under an inverted microscope, while observing a mature biofilm grown for 48 hours in the role of quorum sensing molecules. [Results] the tyrosol group and the control group of early biofilm are hyphal cells mainly; Candida albicans farnesol group and mixed treated early biofilm cells mainly for spore phase. After 48 h of culture of Candida albicans hyphal and spore phase and pseudohyphal forms of cells within the mature biofilm, main hyphal, mixed extracellular polymer matrix. [Conclusion] Tyrosol on Candida albicans hyphae cells in early biofilm formation had no significant role in promoting, while farnesol showed significant inhibition of hyphae formation of early biofilm cells; When farnesol exist in the environment, Even if the high concentration of tyrosol also can not change the inhibition of hyphae. The second part of the quorum sensing molecules early biofilm white Candida HTA1 and regulation of the EFG1 gene expression of the [Materials and methods] preserving Candida albicans recovery of standard strains and clinical isolates with RPMI1640 medium preparation concentration of 1.0 × 10 ^{6 / mL standard bacterial suspension, 5% CO ₂ 37 ° C under the conditions of 50 mL flasks as vector construction early Candida albicans biofilm model. Plant Candida albicans in biofilm growth process, depending on the effect of quorum sensing molecules of three groups treated and control groups: (1): 100μM tyrosol (tyrosol group); (2): 50 μm farnesol (farnesol group ); (3): 50μM the farnesol 500μM Tyrosol (the mixing treatment group); (4): None of quorum sensing molecules (control group). Whether the expression of growth for 90 min early biofilm scraped with a sterile cell scraper, Candida albicans RNA was extracted using Trizol reagent cartridge for RT-PCR test, and observed for the group of protein-coding gene HTA1 and hyphae formation of related genes EFG1 differences. 【Results】 Compared with the control group, the the tyrosol group white Candida enhanced HTA1 expression (P <0.05), the EFG1 the expression did not change significantly (P> 0.05); in farnesol Group HTA1 and EFG1 expression is governed by significantly inhibited (P <0.05); the mixing treatment group HTA1 and EFG1 expression also was significantly inhibited (p <0.05). [Conclusion] can improve the level of transcription of the early Candida albicans biofilm cells HTA1 tyrosol, on the EFG1 the expression no obvious role, farnesol early Candida albicans biofilm cells HTA1 and EFG1 were significantly reduced; When tyrosol and when farnesol simultaneously, the former can not be changed farnesol downward effect on gene expression, the role of the latter is more dominant. The third part of the quorum sensing molecules early biofilm cell proliferation [Materials and Methods] against Candida albicans Candida albicans of preserving the standard strains and clinical isolates of recovery, RPMI1640 culture fluid prepared at a concentration of 1.0 × 10 ^{6 / mL standard bacterial suspension, 5% CO _{build early Candida albicans biofilm model 2} 37 ° C conditions. MTT assay biofilm build carrier for a 96-well cell culture plate, depending on the role of quorum sensing molecules set up three groups of treatment group and a control group: (1): 100μM tyrosol (tyrosol group); (2): 50μM farnesol (farnesol); (3): 50μM the farnesol 500μM Tyrosol (the mixing treatment group); (4): None of quorum sensing molecules (control group). MTT solution and incubated for 4 h early biofilm formation, flip the culture plate discard hole liquid, adding DMSO and shaken for 10 min, 490nm absorbance at values ??determined using a microplate reader (OD ₄₉₀) compare different processing quorum sensing molecules Early Candida albicans biofilm cells proliferation growth. [Results] Compared with the control group, the the tyrosol groups white candidiasis early biofilm cell number was no significant difference (P> 0.05), farnesol group and mixed treatment group the biofilm cell proliferation by significantly inhibited (P <0.05) . [Conclusion] tyrosol against Candida albicans Early proliferation of biofilm cells without a significant role in promoting; farnesol can be suppressed Candida albicans early biofilm cell proliferation, and this inhibition tyrosol the influence from environmental high concentration.}}}

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