FIGURE 3.

YopD associates with Y. enterocolitica 30 S ribosomal particles. A, lysate of Y. enterocolitica W22703 were subjected to hydrophobic interaction chromatography with stepwise increases of ionic strength (buffer B with 1.5 m (NH₄)₂·SO₄). Left, the y axis denotes absorbance at 254 nm to detect ribosomal RNA. Right, the y axis denotes the percentage of buffer B. mAU, milliabsorbance units. The indicated fractions were collected and subjected to transmission electron microscopy, which revealed the purification of 50 S (B), 70 S (C), and 30 S (D) ribosomal particles; scale bars represent 50 nm. E, immunoblot analysis of ribosomal particles purified in A. Polyclonal antisera raised against class II regulatory factors YopD, LcrH, or YscM1 as well as monoclonal antibodies directed against ribosomal protein S3 were used to probe collected fractions. FT = flow-through fractions. Average percentages of YopD or YscM1 in the cleared lysate that are associated with either 30 or 70 S ribosomal particles are listed in Table 1. Images and data analyses are representative examples from three independent experiments.