Page 166 - The Biochemistry of Inorganic Polyphosphates

WU095/Kulaev
WU095-08
Peculiarities of polyphosphate metabolism
150 March 9, 2004 20:32 Char Count= 0
ATP
GTP RNA(DNA) polymerase
CTP RNA(DNA)
UTP
(TTP)
n
(n)PP i PolyP m

(n − 1)PP i + P i PolyP m + 1

Figure 8.15 The hypothetical linkage of PolyPs and nucleic acids biosynthesis in yeast and fungi.

8.10.3 The Relationship between the Metabolism
of Polyphosphates and other Compounds

Besides the correlation between the rates of accumulation of RNA and the PolyP(II) frac-
tion (Kulaev et al., 1973b; Kulaev and Belozersky, 1957; Kulaev and Vagabov, 1983), a
good correlation between the rates of PolyP(IV) accumulation and the synthesis of cell wall
polysaccharides has been revealed (Kulaev et al., 1972d; Vagabov et al., 1973; Tsiomenko
et al., 1974; Shabalin et al., 1979; 1985; Vagabov, 1988). This correlation can be seen in
Figure 8.16. These data suggest a specific interrelation between the metabolisms of these
two compounds, which, although quite different in their chemical nature, are nevertheless
components of the same organelle, namely the cell envelope. The presence of PolyPs in the
cell envelopes of yeast and fungi has been established by using many techniques (Weim-
berg and Orton, 1965; Weimberg, 1970; Kulaev and Afanas’eva, 1970, Voˇr´ıˇsek et al., 1982;
Tijssen et al., 1982, 1983; Tijssen and Van Steveninck, 1984, 1985; Vagabov et al., 1990;
Ivanov et al., 1996). Later, an enzyme dolichyl-diphosphate:polyphosphate phosphotrans-
ferase (EC 2.7.4.20) was found in the membrane fraction of yeast cells (Shabalin et al.,
1979, 1984, 1985; Naumov et al., 1985; Kulaev et al., 1987), and the putative pathway of
joint mannan and PolyP biosynthesis was proposed.
There was some evidence for the possible involvement of PolyPs localized in the cell
periphery in the uptake and phosphorylation of sugars as energy and phosphate donors
(Van Steveninck and Booij, 1964; Hofeler et al., 1987). Later, studies of the mechanisms
of transport-associated phosphorylation of 2-deoxy-D-glucose in the yeast Kluyveromyces
marxianus (Schuddemat et al., 1989b) and Saccharomyces cerevisiae (Schuddemat et al.,
1990) resulted in the conclusion that PolyPs seem to replenish the P i pool and therefore had
an indirect role in sugar transport.

8.10.4 Polyphosphate Fractions at Growth on a P i -Sufficient
Medium with Glucose

Glucose is the most common carbon substrate for many yeasts, and the PolyPs contents at
different growth stages using this energy source has been analysed in detail. A 31 P NMR