Fig. 5
From: Identification of the periplasmic DNA receptor for natural transformation of Helicobacter pylori
Ectopic expression of ComH DNA binding domain (ComH-CTD) restores DNA uptake but not transformation. a Schematic representation of ectopically expressed FLAG-tagged ComH constructs in a ΔcomH genetic background. The upstream sequence (-200 bp) and the coding sequence for the signal peptide of comH (SP) were added to maintain the expression levels of the gene close to that of the wild-type strain. b Subcellular localisation of ComH-FLAG and ComH-CTD-FLAG was monitored by immunoblotting using anti-FLAG antibodies. T: Total extract, P: periplasm, C: cytoplasm. c Fluorescent DNA (ATTO-550-dUTP labelled 408 bp dsDNA) foci formation in the ΔcomH rdxA::comH-CTD-FLAG strain. 3394 cells were counted from at least two independent experiments. 256 (7.5%) bacteria showed presence of detectable DNA foci. Scale bar = 2.5 µm. d Detection of internalised donor DNA in the ΔcomH rdxA::comH-CTD-FLAG strain by the PCR assay. e Comparison of recombination frequencies after natural transformation with genomic DNA of wild-type and ΔcomH rdxA::comH-CTD-FLAG strains. The central line represents the median, the bounds of the boxes show the inner quartile range and the whiskers represent the minimum and maximum values of the data set. The numbers above the box refer to P-values calculated using nonparametric MWU T tests.
