Saccharomyces carlbergensis

The removal of 30-35 % PolyPs from yeast cells during the lysis of cell walls by the snail enzyme was observed in Saccharomyces carlbergensis (Vagabov et al., 1973) - these were alkali-soluble fractions (Table 5.3). A comparative investigation of the amounts of various PolyP fractions was carried out in E. magnusii spheroplasts (Table 5.4.) and some sub-cellular fractions (Table 5.5). All of these data confirm the idea of PolyP localization in different compartments of cells of the lower eukaryotes. 

Figure 7.2 The content of (a) K+, (b) high-molecular-weight PolyP, (c)Zn2+, and (d) low-molecular-weight PolyP during Zn2+ uptake by the yeast Saccharomyces carlbergensis. The incubation medium contained 100 mM glucose and 3 mM ZnS04 (Okorokov et al., 1983b).

The accumulation of Mn2+ in the vacuoles of Saccharomyces carlbergensis (Lichko et al., 1982) correlated well with the increase in PolyP content (Table 7.2). During the accumulation of Mn2+ by S. carlsbergensis, both of the PolyP and Mn2+ contents increased simultaneously. This accumulation took place even when the incubation medium contained no Pi and was accompanied by a simultaneous decrease of Pi content in the vacuoles. This complex-forming function of PolyP may be very important for the yeast cell, since under a short-term phosphate starvation in the presence of metal cations in the medium the vacuolar PolyP content slightly decreases (Table 7.3) (Lichko et al., 1982). A stable Pi content in the cytosol under the above conditions is maintained mainly due to a decrease in the vacuolar P pool but not in the vacuolar PolyP pool. It is probable that the ability of fungi to accumulate large amounts of heavy metals is connected with the PolyP pools, especially in vacuoles. 

Pedersen, M. B. (1986b). DNA sequence polymorphism in the genus Saccharomyces IV. Homologous chromosomes III in Saccharomyces bayanus, S. carlbergensis and S. uvarum. Carlsberg Research Communications, 51, 185-202. 

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