C. Stathopoulos et al., Extensive deproteinization of Dictyostelium discoideum RNase P reveals a new catalytic activity, EUR J BIOCH, 268(7), 2001, pp. 2134-2140
Nuclear Dictyostelium discoideum RNase P was subjected to vigorous deprotei
nization procedures. After treatment with proteinase K followed by phenol e
xtraction of samples containing D. discoideum RNase P activity, a new enzym
atic activity was recovered. The proteinase K/phenol/SDS treated enzyme cle
aves Schizossacharomyces pombe tRNA(Ser) (supS1), D. discoideum tRNASer and
tRNA(Leu) precursors several nucleotides upstream of the cleavage site of
RNase P, liberating products with 5'-hydroxyl ends. This activity seems to
be associated with one or two RNA molecules copurifying with D. discoideum
RNase P activity as judged by its inhibition in the presence of micrococcal
nuclease, which is in contrast to its resistance to proteinase K/phenol/SD
S treatment.