Glucose Level Affects the Regulation of MgaSpn on Virulence and Adaptability of Streptococcus pneumoniae

Streptococcus pneumoniae can regulate virulence gene expression by sensing environmental changes, which is the key to pathogenicity. Carbohydrate is a significant environmental factor affecting the growth and virulence of bacteria. Here, we found that glucose level could affect the content of phosphocholine, which was mediated by MgaSpn. MgaSpn belongs to a virulence regulator (PCVR) family containing phosphotransferase system (PTS) regulatory domains (PRDs). PTS can phosphorylate MgaSpn to varying degrees according to the availability of glucose, thereby altering its virulence regulation. In addition, Transcriptome analysis of wild-type D39s between low and high sugar concentrations revealed that MgaSpn was also involved in the regulation of carbon metabolism inhibition (CCR) and translation process, which made S.pneumoniae still have strong competitiveness in fluctuating environments. In contrast, MgaSpn is closely related to virulence, carbohydrate metabolism, and environmental adaptability of Streptococcus pneumoniae.