Therefore, it is plausible that the optimal extraction was achieved when DNA released from the silica mineral was fragmented to a less extent during incubation. To validate the assumption that opal-CT in sediment needs to be dissolved to release DNA into solution, we tested three additional

sediment samples, the mineralogy of which was confirmed by X-ray diffraction pattern analysis. Two of these samples were primarily composed of opal-A and not consolidated to opal-CT, while another sample was consolidated to opal-CT with a different locality. As shown in Table 4, prokaryotic DNA was not extracted from the sediment selleck kinase inhibitor with opal-CT at 65 °C in 0.33 N NaOH for 50 min, but rather at 94 °C in 0.33 N NaOH for 50 min. In contrast, prokaryotic DNA was extracted from sediment samples with opal-A at 65 °C in 0.33 N NaOH for 50 min rather than at 94 °C in 0.33 N NaOH for 50 min. XRD analysis revealed that opal-CT dissolution was not evident during incubation at 65 °C in 0.33 N NaOH find more for 50 min, which was found to be optimal for DNA extraction from Pseudomonas cells (Fig. 1b and Table S1). These results strengthened our assumption

that DNA is released into solution from the consolidated sediment owing to dissolution of the opal-CT. In this study, a DNA extraction procedure was optimized for the best reproducibility, the shortest incubation time with a reasonable amount of PCR-amplifiable DNA and potentially minimized fragmentation: heating 17-DMAG (Alvespimycin) HCl at 94 °C for 50 min in 0.33 N NaOH solution. DNA extraction method developed in this study has the potential for determining the biosphere globally distributed in deep subseafloor sediments as well as sedimentary rocks from other terrestrial subsurface settings. This study was supported by grants from

the Nuclear and Industrial Safety Agency (NISA) and Japan Nuclear Energy Safety Organization (JNES). “
“Initial analysis has shown that the transcription of the Pseudomonas alcaligeneslipA gene, which encodes an extracellular lipase, is governed by the LipQR two-component system consisting of sensor kinase LipQ and DNA-binding regulator LipR. This study further analyzes lipA gene expression and demonstrates that the RNA polymerase σ54 is involved in the transcription. Purified LipR has an ATPase activity that is stimulated by the presence of lipA promoter DNA. Surface plasmon resonance measurements with purified and in vitro phosphorylated LipR reveal that phosphorylation of LipR is required for specific binding to the upstream activating sequence of the lipA promoter. Furthermore, mass spectrometric analysis combined with mutagenesis demonstrates that Asp52 is the phosphorylated aspartate. This analysis exposes LipR as a prominent member of the growing family of bacterial enhancer-binding proteins. Pseudomonas alcaligenes is a Gram-negative bacterium that efficiently secretes high quantities of commercially relevant enzymes, such as lipases and proteases (Gerritse et al., 1998).