PMC

(A) Sequence logo of the cTP cleavage site, constructed for proteins, for which N-terminally Acetylated semi-tryptic peptides within 10 residues from predicted cTP cleavage site were observed by MS. N-terminally acetylated residue was assumed to represent true cTP cleavage site. (B) Sequence logo of cTP cleavage site, constructed for proteins, for which only non-modified semi-tryptic peptides within 10 residues from predicted cTP cleavage site were observed by MS. N-terminal residue of the semi-tryptic peptide closest to predicted cTP cleavage site was assumed to represent true cTP cleavage site. (C) Sequence logo of 203 stromal proteins for which the most N-terminal peptide (full tryptic or the semi-tryptic peptide) was within 10 residues of the predicted cTP, (D) Sequence logo of the predicted cTP of all 898 annotated Arabidopsis chloroplast proteins, but only those proteins (831) were used with a predicted cTP length of at least 20 aa residues. (E) Sequence logo of the predicted cTP of 802 rice proteins representing the best homologues for 898 annotated Arabidopsis chloroplast proteins, but only those proteins (714) were used with a predicted cTP length of at least 25 aa residues.

The figure shows the structures of UTP and CTP, and the reaction catalyzed by CTP synthetase.

(a) Treatment of PfIspD-wt with 8 at varying CTP concentrations shows the concentration of CTP substrate affects the strength of inhibition at early time points. Five min. IC₅₀ values gave 120 ± 17 nM at 100 μM CTP and 330 ± 57 nM at 400 μM CTP; p = 0.04. Representative data shown; n ≥ 3. (b) Treatment of PfIspD-wt with 8 at varying CTP concentrations shows the concentration of CTP substrate does not affect the strength of inhibition following extended incubation. 50 min. IC₅₀ values gave 49 ± 7.6 nM at 100 μM CTP and 81 ± 13 nM at 400 μM CTP; p = 0.17. Representative data shown; n ≥ 3. (c) Treatment of PfIspD-C202A with 8 at varying CTP concentrations shows the concentration of CTP substrate does not affect the strength of inhibition at early time points. Five min. IC₅₀ values gave 660 ± 130 nM at 100 μM CTP and 860 ± 120 nM at 400 μM CTP; p = 0.32. Representative data shown; n ≥ 3. (d) Treatment of PfIspD-C202A with 8 at varying CTP concentrations shows the concentration of the CTP substrate does not affect the strength of inhibition following extended incubation. 50 min. IC₅₀ values gave 414 ± 86 nM at 100 μM CTP and 470 ± 39 nM at 400 μM CTP; p = 0.57. Representative data shown; n ≥ 3.

ctp genes encode the production of common pili. (A) Gene maps of the ctp cluster and the unlinked pilA gene (Atu3514). The ctp cluster contained nine genes (Atu0216 to Atu0224). Arrows indicate promoters in the ctp cluster. (B) TEM of A. tumefaciens C58, ctp mutants, and complemented derivatives. Arrows, flagella; filled triangles, Ctp pili; open triangles, Ctp pilus bundles. Cells were negatively stained with uranyl acetate and visualized by TEM.