Effects Of Simulated Microgravity On Porphyromonas Gingivalis Strain ATCC33277 Gene Expression

Periodontitis is a periodontium infection caused by the imbalance of subgingival micro-ecology. P. gingivalis is the prime aetiological bacteria of initiation and progression of periodontal disease. It is also the risk factor of many system diseases. Our research group found that under simulated microgravity conditions Streptococcus mutans had obviously morphological changes and its ability of producing WSG and WIG of Streptococcus mutans is inhibited under microgravity condition. This study is aiming to demonstrate the effects of stimulated microgravity (SMG) on P. gingivalis ATCC33277 growth and gene express and the correlations.Methods:We performed the rotary cell culture system (RCCS) to stimulate the microgravity effectively and analyzed the transcriptional adaptation and the changes of growth and genes expression profile by high-throughput RNA sequencing (RNA-Seq). The experimental group is in the microgravity condition and the control group is in the normal gravity. Both group include two sample as the repeat of biology.Results:1. We found the SMG(stimulated microgravity) condition can enhance the bacterium growth during logarithmic phase (P<0.05)2.71 genes were differentially expressed in SMG conditions compared to NG (normal gravity) condition among all the genes of P. g ATCC33277 by global gene expression analysis, including 12 upregulated genes (hagA,traG,etc.) and 59 downregulated genes (fimA,fimC\D\E,mfal,etc.).3. These DEGs were involved in a wide range of biological processes and biological pathways, including modulation of DNA replication, recombination, and repair; energy metabolism; two-component system; one carbon pool by folate; microbial metabolism in diverse environments.Conclusion:1. we established the P.g ATCC33277 microgravity cultured model.2. Microgravity effected the P.g genes expression by two-ways regulation..3. The DEG genes indicated that the abilities of colonization and biofilm formation and oxidative stress were receded, while the abilities of invasion to epithelium cell and endothelium cell, the abilities of transfer of the virulence factors were reinforced under microgravity condition.