TiO2 beads purify nucleotides and inositol phosphates from
mammalian cells. (a) PA extracts from vegetative
D. discoideum (4 × 106 cells)
and the human HCT116 cell line (80 × 106 cells)
were subjected to TiO2 enrichment. After resolving the
extract with PAGE, phosphate-rich molecules were visualized by
toluidine blue staining for comparison with InsP6, ATP
and GTP nucleotide standards. (b)
TiO2-purified HCT116 extract and nucleotide standards
were subjected to apyrase treatment, before resolution by PAGE and
staining with toluidine blue. (c) Two 14 cm dishes
of 80% confluent HeLa, HCT116 and MCF7 cells were treated
with 10 mM sodium fluoride (NaF) for 1 h, before purification of
inositol phosphates with TiO2 beads and resolution by
PAGE with toluidine blue staining. The gels presented are
representative of experiments performed at least three times.