Biology Reference
In-Depth Information
Fig. 2. PCA showing a low signal-to-noise ratio. Two related strains
of Helicobacter pylori
that differ by deletion of ArsS were
grown in pH 5 vs. pH 7 medium, and protein expression was analyzed by DIGE. The experiment was independently repeated
in quadruplicate, resulting in 16 samples coresolved across 8 DIGE gels along with a Cy2-labeled internal standard.
(
a
) Representative DIGE gel from the 8-gel set. (
b
) PCA performed on the unfi ltered 639 features matched across all eight
gels indicated that the majority of variation among these features was consistent with strain-specifi c differences, but no
other correlation with phenotype was revealed in the other principal components. (
c
) Refi ning the PCA to those features that
exhibited a signifi cant change between any group relative to the others (ANOVA
p
< 0.05) revealed that the second principal
component was now consistent with pH-specifi c changes which were the subject of the study. Adapted from ref. (
7
) .
Search WWH ::
Custom Search