K. Moller et al., Ability for anaerobic growth is not sufficient for development of the petite phenotype in Saccharomyces kluyveri, J BACT, 183(8), 2001, pp. 2485-2489
Saccharomyces cerevisiae is a petite-phenotype-positive ("petite-positive")
yeast, which can successfully grow in the absence of oxygen. On the other
hand, Kluyveromyces lactis as well as many other yeasts are petite negative
and cannot grow anaerobically. In this paper, we show that Saccharomyces k
luyveri can grow under anaerobic conditions, but while it can generate resp
iration-deficient mutants, it cannot generate true petite mutants. From a p
hylogenetic point of view, S. kluyveri is apparently more closely related t
o S. cerevisiae than to K. lactis. These observations suggest that the prog
enitor of the modern Saccharomyces and Kluyveromyces yeasts, as well as oth
er related genera, was a petite-negative and aerobic yeast. Upon separation
of the K. lactis and S. kluyveri-S. cerevisiae lineages, the latter develo
ped the ability to grow anaerobically. However, while the S. kluyveri linea
ge has remained petite negative, the lineage leading to the modern Saccharo
myces sensu stricto and sensu late yeasts has developed the petite-positive
characteristic.