Compiling a versatile toolbox for inducible gene expression in .

is a model organism, providing a platform to explore methanoarchaeal regulation mechanisms on the transcriptional and translational level. This study investigates and evaluates various molecular tools to allow inducible gene expression in . (i) The TetR/TetO system was utilized to induce expression of a designed antisense RNA directed against sRNA allowing to increase transcripts of asRNA (500-fold), resulting in a significant decrease of sRNA levels (tetracycline-induced knockdown mutant).

Genome mining in Sorangium cellulosum So ce56: identification and characterization of the homologous electron transfer proteins of a myxobacterial cytochrome P450.

Myxobacteria, especially members of the genus Sorangium, are known for their biotechnological potential as producers of pharmaceutically valuable secondary metabolites. The biosynthesis of several of those myxobacterial compounds includes cytochrome P450 activity. Although class I cytochrome P450 enzymes occur wide-spread in bacteria and rely on ferredoxins and ferredoxin reductases as essential electron mediators, the study of these proteins is often neglected.

The reduced [2Fe-2S] clusters in adrenodoxin and Arthrospira platensis ferredoxin share spin density with protein nitrogens, probed using 2D ESEEM.

We have used X-band ESEEM to study the reduced [2Fe-2S] cluster in adrenodoxin and Arthrospira platensis ferredoxin. By use of a 2D approach (HYSCORE), we have shown that the cluster is involved in weak magnetic interactions with several nitrogens in each protein. Despite substantial differences in the shape and orientational dependence of individual cross-peaks, the major spectral features in both proteins are attributable to two peptide nitrogens (N1 and N2) with similar hyperfine couplings approximately 1.

Mechanism of inhibition of P-glycoprotein mediated efflux by vitamin E TPGS: influence on ATPase activity and membrane fluidity.

Efflux pump (e.g., P-gp, MRP1, and BCRP) inhibition has been recognized as a strategy to overcome multi-drug resistance and improve drug bioavailability.

Spectroscopic and biochemical studies on protein variants of quinaldine 4-oxidase: Role of E736 in catalysis and effects of serine ligands on the FeSI and FeSII clusters.

Quinaldine 4-oxidase (Qox), which catalyzes the hydroxylation of quinaldine to 1H-4-oxoquinaldine, is a heterotrimeric (LMS)2 molybdo-iron/sulfur flavoprotein belonging to the xanthine oxidase family. Variants of Qox were generated by site-directed mutagenesis. Replacement in the large subunit at E736, which is presumed to be located close to the molybdenum, by aspartate (QoxLE736D) resulted in a marked decrease in kcat app for quinaldine, while Km app was largely unaffected.