Role of PO₄-ion during the Glucose Metabolism of Streptococcus mutans and Other Non-cariogenic Streptococci under Aerobic and Anaerobic Conditions

Abstract

The glucose metabolism of streptococcus mutans and streptococcus sanguis was examined anaerobically in a buffer containing NaHCO₃+KH₂PO₄.
Streptococcus mutans produced more acetic acid and formic acid in a buffer without KH₂PO₄than in a buffer containing KH₂PO₄.
Production of lactic acid by str. sanguis increases with increasing KH₂PO₄ concentration.
The oxygen uptake of these streptococci in hydroxyl-apatite and in enamel powder was examined. Oxygen uptake was almost nil when str. mutans was grown in B.H.I. broth, but it increased considerably when the culture medium was B.H.I. broth+5% sucrose. Str. sanguis did not show this variation.