The use of blocking reagent, hybridization procedure and chemilum

The use of blocking reagent, hybridization procedure and chemiluminescent selleck detection with CSPD chemiluminescent substrate (Roche) was according to standard protocols. Complementation of

deletions Deleted genes were reintroduced into all deletion strains in cis. Complementation plasmids for each deletion were constructed by PCR amplification of the deleted gene(s) together with the flanking regions from H. salinarum R1 genomic DNA using the external primers (us_fo, ds_re) used for deletion plasmid construction. Inserts were digested with the respective restriction enzymes CH5424802 research buy and cloned into pMS3, and the resulting plasmids were verified by sequencing of the insert. Each deletion strain was transformed with the corresponding complementation plasmid, and a double crossover triggered as described above. Red colonies were inoculated into complex medium and screened for reintroduction of the target gene by PCR using the primers spanning the flanking regions. Quantitative Realtime RT-PCR Total RNA from 5 ml late log-phase cultures was isolated using the peqGOLD RNAPure™ system according to manufacturer’s instructions. 3 μg total RNA were reverse transcribed with 50 pmol random hexamer primer (Applied

Biosystems, Darmstadt, Germany) using Superscript III (Invitrogen, Karlsruhe, Germany). The quantitative PCR KU55933 cost reactions were done in a GeneAmp 5700 Sequence Detection System (Applied Biosystems) using the SYBR Green PCR Master Mix Kit (Applied Biosystems). The final reaction volume was 25 μl with 0.5 μl of the reverse transcription reaction

as template. Primers (see Additional file 7) were applied in a final concentration of 0.5 μM. Controls without template and control reactions amplifying a non-coding DNA region (the bop promoter) were included. The PCR consisted of 10 min initial denaturation at 95°C and 40 cycles of 15 sec 95°C and 1 min 60°C. Uniformity of the product was assured by measuring the melting curve of the product. Transcript level differences were calculated by the ΔΔC t method using the constitutively expressed fdx gene (OE4217R) as internal standard. For all calculations the mean-C t of 2 replicate reactions was used. Results were accepted if the C t of both 4��8C replicates differed by less than 0.5, and if the difference to the lowest C t of the controls was at least 5. Swarm plates Semi-solid agar plates were prepared from complex medium with 0.25% agar. Wild type and deletion cultures were grown to an OD600 of 0.6 – 0.8. Fresh medium was inoculated with equal amount of cells from the starter cultures and culturing repeated twice to achieve equal cell densities in the final cultures. 10 μl of culture with an OD600 of 0.6 – 0.8 were injected with a pipette tip into the soft agar. The plates were incubated for 3 days at 37°C in the dark.

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