Streptococcus mutans의 gtfB 및 gtfC 유전자 발현에 대한 당의 영향 = The effects of sugars on the expression of gtfB and gtfC mrna

국문 초록 (Abstract)

Streptococcus mutans Ingbritt의 비수용성 글루칸을 합성하는 효소인 glucosyltransferase B 및 C의 mRNA 발현에 대한 각 당의 영향을 fluorescent in situ hybridization (FISH) 방법으로 관찰하여 다음의 결과를 얻었다.
1. 1% 설탕이 함유된 BHI 배지에서 S. mutans Ingbritt를 접종하여 배양할 때 배양 9시간 째 gtfB 및 gtfC 유전자의 mRNA가 발현이 급격히 증가하였다.
2. BHI 액체배지에 설탕을 첨가한 경우 gtfB 및 gtfC 유전자의 mRNA가 발현되었으며, 10% 설탕을 첨가한 경우 1%와 5%보다 gtfB 및 gtfC 유전자의 발현이 감소되었다.
3. 1% 설탕이 첨가된 BHI 액체 배지에 당을 첨가한 경우 포도당은 10% 첨가하였을 때 gtfB 및 gtfC 유전자의 mRNA 발현이 감소하였고, 과당의 경우 1% 첨가한 경우 감소하여 5%와 10%에서는 gtfB 및 gtfC 유전자가 거의 발현되지 않았다.
4. 자일리톨의 경우 1%부터 gtfB 및 gtfC 유전자 mRNA 발현이 대조군보다 감소하였고, 5%와 10%에서는 두 유전자 모두 발현이 현저하게 감소하였다.
5. 유당의 경우 두 유전자의 발현에 거의 영향을 미치지 않는 것으로 관찰되었고, 솔비톨의 경우 각 농도에서 두 유전자의 발현이 대조군보다 감소하였다.
결론적으로 비수용성 글루칸 합성하는 gtfB 및 gtfC 유전자의 mRNA 발현이 포도당, 과당, 자일리톨 첨가에 의해 감소함을 알 수 있었다.

다국어 초록 (Multilingual Abstract)

Insoluble glucan is the important component of oral biofilm, which is synthesized from sucrose through the action of glucosyltransferase (GTF) B and GTF C encoded by the gtfB and gtfC genes, respectively of Streptococcus mutans. In present study, the effects of various sugars on the mRNA expression of gtfB and gtfC of S. mutans Ingbritt were examined by fluorescent in situ hybridization (FISH). The mRNA of gtfB and gtfC was expressed normally in the BHI broth containing 1% and 5% sucrose. The mRNA expression was decreased by the addition of 10% of glucose, and 1%, 5% and 10% of fructose. Lactose had no great effect on the expression of gtfB and gtfC 5% and 10% of xylitol greatly reduced the mRNA expression of gtfB and gtfC. Sorbitol slightly decreased the mRNA expression of gtfB and gtfC when compared to the control. In summary, mRNA expression of gtfB and gtfC was decreased by the addition of glucose, fructose, and xylitol.

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