Statistics 19

Statistical methods used included paired t-tests for comparison of mean values. All analyses were carried out using SPSS Statistics 19.0. P < 0.05 was considered statistically significant.

All data are expressed as the mean ± standard deviation. Various groups were compared for differences using one-way analysis of variance (one-way ANOVA). All analyses were performed using SPSS Statistics 19.0. A difference with a P-value of <0.05 was deemed statistically significant.

The levels association of growth rate, biofilm and cell adhesion between A. baumannii ATCC 19606 and the mutant strains were analysed using the SPSS Statistics 19.0 software. According to the normality test and homogeneity of variances test, the levels of growth rate, biofilm and cell adhesion appear to be a normal distribution with equal variance, so all the data was adopted with analysis of variance (ANOVA) statistical test. The survival rate of mice was compared by Chi-Squared Test (Fisher probabilistic method). Statistical significance was established by using a conventional level of P < 0.05.

The DEGs results were validated using qRT-PCR. The qRT-PCR assays were performed with three replicates, and the actin gene was used as an internal control to normalize the expression level of the target genes. The specific primers were designed according to the unigene sequences using Primer 5.0 software (Table S1).
Amplifications were performed on a 96-well plate with a 25 μL reaction volume containing 1 μL cDNA (50ng), 10 μL SsoFastTM EvaGreen® Supermix (BIO-RAD, CA, USA), 0.5 μL 10 μM of primers, and 13 μL of ddH₂O. The PCR temperature profile was 95 °C for 30 s followed by 40 cycles of 94 °C for 15 s, 58 °C for 20 s and 72 °C for 20 s, with a 0.5 °C/5 s incremental increase from 60 °C to 95 °C. The relative copy number of mRNA was calculated according to the 2^{− ∆∆CT} comparative CT method^{38 (link)}. Quantitative data were expressed as means ± SD. Two-side t test was used to compare expression levels. A probability level of 0.05 was used to indicate significance. All statistics were performed using SPSS Statistics 19.0.

All data were expressed as the mean±S.E.M. from at least three independent experiments. One- or two-way ANOVA followed by Tukey's post-test was used to compare values among different experimental groups using the SPSS Statistics 19.0 program. Student's t-test and two-tailed Student's t-test were used for experiments that contain only two groups. A value of P<0.05 was considered statistically significant, and a value of P<0.01 was considered highly significant.

The films were scanned as gray scale 8-bit images and the density of bands were determined by the ImageJ software.The data of relative quantity in western blot are presented and the statistical analysis of variance between groups was performed by SPSS Statistics 19.0 software. Significant difference of all statistical tests was set at 0.05 (p<0.05).