Streptococcus durans

Streptococcus thermophilus H Streptococcus thermophilus T Streptococcus lactis 9 Lactobacillus easel Streptococcus durans Micrococcus 8406... 

When grown in alkaline media, certain species of lactic acid bacteria decrease production of LDH, resulting in increased formation of formate, acetate, and ethanol as end products. This phenomenon has been observed in S. faecalis subsp. liquefaciens (Gunsalus and Niven 1942), Streptococcus durans, S. thermophilus, (Platt and Foster 1958), and Lactobacillus bulgaricus (Rhee and Pack 1980). Data of Rhee and Pack (1980) indicate that a phosphoroclastic split of pyruvate occurs under alkaline conditions to yield ATP. The enzymes involved in this reaction (pyruvate formate-lyase and acetate kinase) require alkaline conditions for optimum activity. A shift from homo- to heterofermentation because of increased pH has not been observed for Group N streptococci. 

Aksoy, A., Duran, N., and Koksal, F. 2006. In vitro and in vivo antimicrobial effects of mastic chewing gum against Streptococcus mutans and mutans streptococci. Am/i. Oral Biol. 51 476-481. 

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