Bacterial survival in serum was determined with minor modifications [57]. First, The bacteria were grown to log phase in selleck screening library LB broth and the viable bacterial concentration was adjusted to 1 × 106 colony forming

units/ml. 1 ml of the cultures was washed twice by using phosphate-buffered saline (PBS) and resuspended in 1 ml PBS. The mixture containing 250 μl of the cell suspension and 750 μl of Trichostatin A ic50 pooled human serum was incubated at 37°C for 60 min. The number of viable bacteria was then determined by plate counting. The survival rate was expressed as the number of viable bacteria treated with human serum compared to the number of pre-treatment. The assay was performed triple, each with triplicate samples. The data from one of the representative experiments are shown and expressed as the mean and standard deviation from the three samples. The 0% survival of K. pneumoniae CG43S3ΔgalU served as a negative control. CAS assay The CAS assay was performed according to the method described by Schwyn and Neilands [66]. Each of the bacterial strain was grown overnight in M9 minimal medium, and then 5 μl of culture was added onto a CAS agar plate. After 24 hr Lazertinib in vitro incubation at 37°C, effects of the bacterial siderophore production could be observed. Siderophore production was apparent as an orange halo around the colonies; absence of a halo indicated the inability to produce siderophores.

Statistical method An unpaired t-test was used to determine the

statistical significance GBA3 and values of P < 0.001 were considered significant. The results of CPS quantification and qRT-PCR analysis were derived from a single experiment representative of three independent experiments. Each sample was assayed in triplicate and the mean activity and standard deviation are presented. Acknowledgements The work is supported by the grants from National Science Council (NSC 97-2314-B-039-042-MY2 and NSC 99-2320-B-039-002-MY3) and China Medical University (CMU98-ASIA-01 and CMU99-ASIA-07). Electronic supplementary material Additional file 1: Figure S1: RyhB pairs with sitA. The file contains supplemental figure S1 that the potential base pairing in RyhB/sitA mRNA in this study. (PPT 136 KB) Additional file 2: Table S1: Primers used in this study. The file contains supplemental Table S1 that the detailed information of primer sets used in this study. (DOC 64 kb) (DOC 64 KB) References 1. Chou FF, Kou HK: Endogenous endophthalmitis associated with pyogenic hepatic abscess. J Am Coll Surg 1996,182(1):33–36.PubMed 2. Han SH: Review of hepatic abscess from Klebsiella pneumoniae. An association with diabetes mellitus and septic endophthalmitis. West J Med 1995,162(3):220–224.PubMed 3. Lau YJ, Hu BS, Wu WL, Lin YH, Chang HY, Shi ZY: Identification of a major cluster of Klebsiella pneumoniae isolates from patients with liver abscess in Taiwan. J Clin Microbiol 2000,38(1):412–414.PubMed 4.