0000000000977753
AUTHOR
Matti Karp
showing 2 related works from this author
Expression and purification of polyhistidine-tagged firefly luciferase in insect cells
2001
The coleopteran firefly, Photinus pyralis, luciferase was produced in lepidopteran Trichoplusia ni insect cells using a baculovirus expression vector. The recombinant protein was equipped with a polyhistidine affinity tag at the carboxyl terminus and purified by immobilized metal-ion affinity chromatography in combination with an expanded bed adsorption system. This approach enabled an efficient, one-step purification protocol of a genetically modified luciferase with properties similar to those of the authentic counterpart. According to light emission measurements, the final yield of highly purified protein was 23 mg l−1 of cell culture. In addition, no specific interaction of interfering …
Effect of Cd-containing wood ash on the microflora of coniferous forest humus
2000
The use of wood ash in forestry has been questioned because the cadmium (Cd) concentration of ash, which varies between 1 and 20 mg kg(-1) ash, exceeds the level allowed for fertilizers (3 mg kg(-1)) used in agriculture. To investigate the combined and separated effects of Cd and ash on the forest humus microflora, pumice or wood ash, spiked with a water-soluble (CdCl(2)) or -insoluble (CdO) form of Cd at three levels (0, 400 and 1000 mg kg(-1)), were applied at a fertilization level of 5000 kg ha(-1) in a laboratory microcosm study. The trial consisted of 60 microcosms (five replications per treatment), which were incubated in darkness at +20 degrees C and a constant relative air humidity …