Megasphaera cerevisiae

Engelmann, U., Weiss, N. (1985). Megasphaera cerevisiae sp. nov. a new gram-negative obligately anaerobic coccus isolated from spoiled beer. Systematic and Applied Microbiology, 6(3), 287-290. 

Megasphaera cerevisiae strains form a uniform group in terms of utilized carbon sources that include arabinose, fructose, lactic acid and pyruvic acid (Engelmann Weiss, 1985). 

Megasphaera cerevisiae is moderately acid tolerant. It still grows weakly in laboratory media at pH 4.1. 2 but not anymore at pH 4.0 (Haikara, 1989). The acid tolerance of the other beer-related species has not been studied. The growth tanpera-ture of the beer-spoilage species ranges from 15 to 37 °C (Haikara, 1989 Juvonen Snihko, 2006). M. cerevisiae appears to tolaate oxygen at least at low temperatures (Juvonen, 2009). The antibiotic sensitivity of the type strains has been studied. All the type strains are resistant to vancomycin. M. sueciensis and M. paucivorans are also resistant to cohstin, whereas M. cerevisiae is sensitive to this compound (Juvonen Snihko, 2006). 

Figure 9A Beer spoiled by Megasphaera cerevisiae (left) and Pectinatus frisingensis (right).

Doyle, L. M., Mclnemey, J. O., Mooney, J., Powell, R., Haikara, A., Moran, A. P. (1995). Sequence of the gene encoding the 16S rRNA of the beer spoilage organism Megasphaera cerevisiae. Journal of Industrial Microbiology, 15, 61-IQ. 

Watier, D., Chowdhury, I., Leguerinel, I., Homez, J. P. (1996a). Survival of Megasphaera cerevisiae heated in laboratory media, wort and beer. Food Microbiology, 13, 205—212. 

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