Growth curve analysis of the complementation of E. coli htrA- temperature sensitive phenotype by C. trachomatis htrA . (A. B.) Growth of E. coli strains at 30°C (A) and 44°C (B). Samples are: Solid line; MG1655: wild-type E. coli,; dashed line: htrA-, dotted line: htrA-pACYC184, dashed and dotted line; htrA-pACYCEcHtrA, large dashed line, htrA-pACYCCTHtrA. Triplicate cultures were conducted for each experiment, with standard deviations indicated by the error bars. (C) Western blot of the total E. coli extracts for CtHtrA protein. Samples are: (1–8: 30°C) 1: E. coli MG1655, 2: E. coli MG1655 pACYCcthtrA, 3: E. coli htrA-pACYC184, 4: E. coli htrA-pACYCechtrA, 5: E. coli htrA-pACYCcthtrA, (6–9 44°C) 6: E. coli MG1655 pACYCcthtrA, 7: E. coli htrA-pACYCechtrA, 8: E. coli htrA-pACYCcthtrA, 9: purified recombinant HtrA protein. Chlamydia culture samples are included; 10. total extract HEp-2 cells, 11. total extract HEp-2 C. trachomatis L2 infected (20 h PI).