ZZE-Configuration of chromophore ß-153 in C-phycocyanin from Mastigocladus laminosus

The photochemistry of C-phycocyanin has been studied after denaturation in the dark. It shows an irreversible reaction which has characteristics of a Ζ,Ζ,Ε- to Z,Z,Z-isomerization of dihydrobilins. Its amplitude depends on the reaction conditions, with a maximum corresponding to 15% conversion of one of the three PC chromophores. This chromophore is suggested to be ß-153, for which recent X-ray data T. Schirmer, W. Bode, and R. Huber, J. Mol. Biol., submitted, show ring D being highly twisted out of the plane of the other rings. During unfolding, there is thus a probability of falling into the photochemically labile Z,Z,^-configuration

Primitiver neuroektodermaler Tumor im Hoden: Molekulare Analyse und Diskussion der Entstehung

Zusammenfassung: Wir beschreiben einen testikulären primitiven neuroektodermalen Tumor (PNET) mit intratubulärer Keimzellneoplasie des angrenzenden Hodenparenchyms bei einem 25-jährigen Patienten. Testikuläre PNET sind selten. Ihre Entstehung wird auf eine maligne somatische Transformation in einem testikulären Keimzelltumor zurückgeführt. Morphologisch und molekularpathologisch ähneln diese Tumoren kindlichen zentralen PNET, die keine Rearrangierung des EWS-Gens auf Chromosom22 aufweisen. Auch im hier beschriebenen Fall konnte keine Translokation nachgewiesen werde

Arxula adeninivorans Recombinant Urate Oxidase and Its Application in the Production of Food with Low Uric Acid Content

Hyperuricemia and its symptoms are becoming increasingly common worldwide. Elevated serum uric acid levels are caused by increased uric acid synthesis from food constituents and reduced renal excretion. Treatment in most cases involves reducing alcohol intake and consumption of meat and fish or treatment with pharmaceuticals. Another approach could be to reduce uric acid level in food, either during production or consumption. This work reports the production of recombinant urate oxidase by Arxula adeninivorans and its application to reduce uric acid in a food product. The A. adeninivorans urate oxidase amino acid sequence was found to be similar to urate oxidases from other fungi (61-65% identity). In media supplemented with adenine, hypoxanthine or uric acid, induction of the urate oxidase (AUOX) gene and intracellular accumulation of urate oxidase (Auoxp) was observed. The enzyme characteristics were analyzed from isolates of the wild-type strain A. adeninivorans LS3, as well as from those of transgenic strains expressing the AUOX gene under control of the strong constitutive TEF1 promoter or the inducible AYNI1 promoter. The enzyme showed high substrate specificity for uric acid, a broad temperature and pH range, high thermostability and the ability to reduce uric acid content in food

Arxula adeninivorans Recombinant Guanine Deaminase and Its Application in the Production of Food with Low Purine Content

Purines of exogenous and endogenous sources are degraded to uric acid in human beings. Concentrations >6.8 mg uric acid/dl serum cause hyperuricemia and its symptoms. Pharmaceuticals and the reduction of the intake of purine-rich food are used to control uric acid levels. A novel approach to the latter proposition is the enzymatic reduction of the purine content of food by purine-degrading enzymes. Here we describe the production of recombinant guanine deaminase by the yeast Arxula adeninivorans LS3 and its application in food. In media supplemented with nitrogen sources hypoxanthine or adenine, guanine deaminase (AGDA) gene expression is induced and intracellular accumulation of guanine deaminase (Agdap) protein occurs. The characteristics of the guanine deaminase isolated from wild-type strain LS3 and a transgenic strain expressing the AGDA gene under control of the strong constitutive TEF1 promoter were determined and compared. Both enzymes were dimeric and had temperature optima of 55°C with high substrate specificity for guanine and localisation in both the cytoplasm and vacuole of yeast. The enzyme was demonstrated to reduce levels of guanine in food. A mixture of guanine deaminase and other purine degradation enzymes will allow the reduction of purines in purine-rich foods

Aadh2p: an Arxula adeninivorans alcohol dehydrogenase involved in the first step of the 1-butanol degradation pathway

Additional file 3: Figures S3. Key compounds of the ß-oxidation - microarray studies. The SBGN style metabolic network depicts reversible (double headed arrow) and irreversible (single headed arrow) reactions catalyzed by the corresponding enzymes (rectangular square). Enzymes are enriched with color-coded fold change values of time resolved expression data of the respective genes. The colors represent upregulation (blue) and downregulation (red) of genes in cells shifted to medium containing 1-butanol as the carbon source compared to cells grown with glucose. Metabolites or enzymes occurring multiple times in the metabolic network are decorated with a clone marker (e.g. CoA) (produced using VANTED [2, 3])