Magnesium-Dependent Promotion of H2O2 Production Increases Ecological Competitiveness of Oral Commensal Streptococci

X. Cheng, S. Redanz, P. Treerat, H. Qin, D. Choi, X. Zhou, X. Xu, J. Merritt, J. Kreth

Research output: Contribution to journalArticlepeer-review

11 Scopus citations


The pyruvate oxidase (SpxB)–dependent production of H2O2 is widely distributed among oral commensal streptococci. Several studies confirmed the ability of H2O2 to antagonize susceptible oral bacterial species, including caries-associated Streptococcus mutans as well as several periodontal pathobionts. Here we report a potential mechanism to bolster oral commensal streptococcal H2O2 production by magnesium (Mg2+) supplementation. Magnesium is a cofactor for SpxB catalytic activity, and supplementation increases the production of H2O2 in vitro. We demonstrate that Mg2+ affects spxB transcription and SpxB abundance in Streptococcus sanguinis and Streptococcus gordonii. The competitiveness of low-passage commensal streptococcal clinical isolates is positively influenced in antagonism assays against S. mutans. In growth conditions normally selective for S. mutans, Mg2+ supplementation is able to increase the abundance of S. sanguinis in dual-species biofilms. Using an in vivo biophotonic imaging platform, we further demonstrate that dietary Mg2+ supplementation significantly improves S. gordonii oral colonization in mice. In summary, our results support a role for Mg2+ supplementation as a potential prebiotic to promote establishment of oral health–associated commensal streptococci.

Original languageEnglish (US)
Pages (from-to)847-854
Number of pages8
JournalJournal of dental research
Issue number7
StatePublished - Jul 1 2020


  • Streptococcus gordonii
  • Streptococcus sanguinis
  • hydrogen peroxide
  • magnesium
  • oral biofilm
  • pyruvate oxidase

ASJC Scopus subject areas

  • Dentistry(all)


Dive into the research topics of 'Magnesium-Dependent Promotion of H2O2 Production Increases Ecological Competitiveness of Oral Commensal Streptococci'. Together they form a unique fingerprint.

Cite this