The invention at hand provides a novel protein for the chemoenzymatic and enantiomerically pure production of L-<i>threo</i>-hydroxyaspartate from L-aspartate.<p>
The naturally occurring protein AsnO (asparagine oxygenase) is part of the CDA biosynthesis gene cluster in Streptomyces coelicor. AsnO is an Fe<sup>2+</sup> and <font face=”symbol”>a</font>-ketoglutarate-dependent hydroxylase. This hydroxylase acts as a building block for non-ribosomally produced CDA (?Calcium-dependent antibiotic?) in vivo. During the catalytic cycle, this class of enzymes couples the oxidative decomposition of <font face=”symbol”>a</font>-ketoglutarate to succinate and CO<sub>2</sub> with the hydroxylation of the substrate (L-asparagine).<p>
In the wild type of AsnO, the side chain of the amino acid residue Asp-241 thereby binds to the NH<sub>2</sub> group of the carboxamide group of L-Asn.
Surprisingly, it was found that directed mutagenesis of Asp-241 to Asn-241 (D241N) results in a binding site for the carboxyl group of an aspartate side chain. By means of this directed mutagenesis, the substrate specificity changes from asparagine to aspartate, and the mutated protein converts aspartate chemoenzymatically to L-threo-hydroxyaspartate in the presence of Fe2+ and a-ketoglutarate.<p>
Thereby, AsnO D241N represents the mutant of the wild type AsnO according to the present invention.
The invention is a procedure to reduce the bit fault rate in UMTS networks and thus to allow to process more data simultaneously, to reduce the required…
In industrial applications of MIG welding of aluminium usually wires with a diameter of 1.0 mm to 1.6 mm are used. Filler metals with smaller wire diameters…
The generation of protons by irradiating thin foils by ultra short laser pulses (laser-driven proton beams) has recently
gained enormous attention. These…
hydroFUEL – ecologically compatible diesel fuel
hydroFUEL is an absolutely stable microemulsion that is bicontinuous – i.e. both the oil and the water…
Scientists at the University of Cologne have developed a new inducible expression system, which is easy to use, reliable and very fast. The System is based on…
Scientists at the University of Bonn have identified new small molecules which can be used for the treatment of diseases characterized by alterations of…
Scientists at the University of Bonn, Germany, have identified the main target antigen for the atypical antineutrophil
cytoplasmic antibodies pANCA in…
Scientists of the Georg-August-University of Göttingen identified a new source of adult somatic stem cells, the spermatogonial stem cells (SSC). These cells…
Invention
Scientists at the University of Münster, Germany, have isolated and characterized a novel substance class from Cocoa. CocoaHeal is capable of…
The new material density sensor enables contactless and highly sensitive mass flow measurements of dielectric materials transported in pipe lines or with…
The invention enables surgeons to monitor the quality of anastomosed vessels by measuring the blood pressure above and below the junction. Fiber-optic sensors…
Cottbus College of Applied Sciences (BTU Cottbus) recently developed and tested a process for forming metal-foam sandwiches (foam-coated aluminium or other…
Calorimetric measurement of the vapour-liquid phase equilibrium in compoundsFurther Information: PDF ZAB ZukunftsAgentur Brandenburg GmbH BrainshellPhone: +49…
This invention provides a novel technique for manufacturing composite materials, namely plastics reinforced with natural fibres. Because all kinds of natural…
The invention permits low-cost preparation and processing of freshly harvested natural fibres for the production of natural raw materials. The invention…
Feedback
