Co-Immobilization of RizA Variants with Acetate Kinase for the Production of Bioactive Arginyl Dipeptides.

The biocatalytic system comprised of RizA and acetate kinase (AckA) combines the specific synthesis of bioactive arginyl dipeptides with efficient ATP regeneration. Immobilization of this coupled enzyme system was performed and characterized in terms of activity, specificity and reusability of the immobilisates. Co-immobilization of RizA and AckA into a single immobilisate conferred no disadvantage in comparison to immobilization of only RizA, and a small addition of AckA (20:1) was sufficient for ATP regeneration.

Mycelium vs. Fruiting Bodies of Edible Fungi-A Comparison of Metabolites.

Edible mushrooms are widely appreciated for their appealing flavours, low caloric values and high content of presumably health-protecting metabolites. Their long history of safe use together with the looming worldwide food crisis have revived the idea of generating meat analogues and protein isolates by the controlled fermentation of mycelia of these edible fungi as a dietary option. The occurrence of proteins, polysaccharides, smaller metabolites, metal ions and toxins in mycelia and fruiting bodies is compared among the three most popular species, (button mushroom), (oyster mushroom), (shiitake) and some closely related species.

Baeyer-Villiger monooxygenases from Yarrowia lipolytica catalyze preferentially sulfoxidations.

Nine new putative Baeyer-Villiger monooxygenase encoding genes were identified in the eukaryote Yarrowia lipolytica and eight were subsequently cloned and expressed. These enzymes, Yarrowia monooxygenases A-H (YMOA-H), were used in biocatalysis reactions with ketones, sulfides and sulfoxides as substrates. YMOB converts ketones and sulfides, albeit with low activities.

Switch in Cofactor Specificity of a Baeyer-Villiger Monooxygenase.

Baeyer-Villiger monooxygenases (BVMOs) catalyze the oxidation of ketones to esters or lactones by using molecular oxygen and a cofactor. Type I BVMOs display a strong preference for NADPH. However, for industrial purposes NADH is the preferred cofactor, as it is ten times cheaper and more stable.