Ra. Poot et al., ACETYLATION OF RIBOSOMAL-PROTEIN S5 AFFECTED BY DEFECTS IN THE CENTRAL PSEUDOKNOT IN 16S RIBOSOMAL-RNA, FEBS letters, 401(2-3), 1997, pp. 175-179
We have analyzed the ribosomal protein profile of Escherichia coli 30S
subunits with the mutation C(18)A in the central pseudoknot of their
16S ribosomal RNA, This mutation was shown to inhibit translational ac
tivity in vivo and to affect ribosome stability in vitro, The majority
of the mutant 30S particles were present as free subunits in which a
reproducible decrease in amount of proteins S1, S2, S18 and S21 was ob
served, The protein gels also showed the appearance of a satellite ban
d nest to S5, This band reacted with anti-S5 antibodies and had a slig
htly increased positive charge, The simplest interpretation of these f
indings, also considering published data, is that the satellite band i
s S5 with a non-acetylated N-terminal alanine, Underacetylation of S5
due to mutations in the 16S rRNA implies that the modification is perf
ormed on the ribosome.