Effects of the polyhistidine tag on kinetics and other properties of trehalose synthase from Deinococcus geothermalis.

Two recombinant trehalose synthases from Deinococcus geothermalis (DSMZ 11300) were compared. A significant influence of the artificial polyhistidine tag was observed in protein constitution. The recombinant trehalose synthase from D.

Properties of recombinant trehalose synthase from Deinococcus radiodurans expressed in Escherichia coli.

A trehalose synthase gene from Deinococcus radiodurans (DSMZ 20539) containing 1659 bp reading frame encoding 552 amino acids was amplified using PCR. The gene was finally ligated into pET30Ek/LIC vector and expressed after isopropyl β-d-thiogalactopyranoside induction in Escherichia coli (DE3) Rosetta pLysS. The recombinant trehalose synthase (DraTreS) containing a His(6)-tag at the C-terminus was purified by metal affinity chromatography and characterized.

Sources, properties and suitability of new thermostable enzymes in food processing.

Investigations concerning recombinant a-amylases from Pyrococcus woesei and thermostable a-glucosidase from Thermus thermophilus indicate their suitability for starch processing. Furthermore, the study of recombinant ss-galactosidase from Pyrococcus woesei suitable for purpose of low lactose milk and whey production are also presented. The activity of this enzyme in a wide pH range of 4.

Cloning of the thermostable alpha-amylase gene from Pyrococcus woesei in Escherichia coli: isolation and some properties of the enzyme.

Pyrococcus woesei (DSM 3773) alpha-amylase gene was cloned into pET21d(+) and pYTB2 plasmids, and the pET21d(+)alpha-amyl and pYTB2alpha-amyl vectors obtained were used for expression of thermostable alpha-amylase or fusion of alpha-amylase and intein in Escherichia coli BL21(DE3) or BL21(DE3)pLysS cells, respectively. As compared with other expression systems, the synthesis of alpha-amylase in fusion with intein in E. coli BL21(DE3)pLysS strain led to a lower level of inclusion bodies formation-they exhibit only 35% of total cell activity-and high productivity of the soluble enzyme form (195,000 U/L of the growth medium).

Production, properties, and some new applications of chitin and its derivatives.

Chitin is a polysaccharide composed from N-acetyl-D-glucosamine units. It is the second most abundant biopolymer on Earth and found mainly in invertebrates, insects, marine diatoms, algae, fungi, and yeasts. Recent investigations confirm the suitability of chitin and its derivatives in chemistry, biotechnology, medicine, veterinary, dentistry, agriculture, food processing, environmental protection, and textile production.