Expression of ssrA in non-pathogen-induced adaptation in the oral cavity through signal exchange with oral pathogens

Kim, Sung Ryoul; Kwak, Jae Woo; Lee, Sung Ka; Jung, Seung Gon; Han, Man Seung; Kim, Bang Sin; Kook, Min Suk; Oh, Hee Kyun; Park, Hong Ju

Abstract

INTRODUCTION
This study was conducted to evaluate ssrA expression resulting from adaptation of Escherichia coli (E. coli) to oral pathogens through signal exchange.
MATERIALS AND METHODS
Human cell lines Hep2 and HT29, wild-type E. coli (WT K-12), ssrA knock-out E. coli (Delta K-12), and Scleropages aureus (S. aureus) were used. A single culture consisting of Hep2, HT29, WT K-12, and Delta K-12, and mixed cultures consisting of Hep2 and WT K-12, Hep2 and Delta K-12, WT K-12 and S. aureus , Delta K-12 and S. aureus , and Hep2, WT K-12, and S. aureus were prepared. For HT29, a mixed culture was prepared with WT K-12 and with WT K-12 and S. aureus. Total RNA was extracted from each culture with the resulting expression of ssrA, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kappaB), and p53 was evaluated by Reverse transcription polymerase chain reaction (RT-PCR).
RESULTS
The expression of ssrA in a single culture of WT K-12 was lower than that observed in the mixed culture of WT K-12 with S. aureus. Greater ssrA expression was observed in the mixed culture of WT K-12 with Hep2 than in the single culture of WT K-12. The expression of NF-kappaB was higher in the mixed culture of Hep2 with Delta K-12 than that in the mixed culture of Hep2 with WT K-12, and was lowest in the single culture of Hep2. The expression of ssrA was higher in the mixed culture of WT K-12 with Hep2 and S. aureus than in the mixed culture of WT K-12 with Hep2.
CONCLUSION
These results suggest that ssrA plays an important role in the mechanism of E. coli adaptation to a new environment.