Jiri Janata

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We report on a CMOS-based microsensor array, featuring 576 electrodes and 24 channels, for label-free electrochemical detection of DNA hybridization. Each channel comprises a potentiostatic circuit that keeps the electrode at a defined potential and measures the respective electrical current. The readout channels rely on a first-order delta-sigma(More)
The possibility that weak, ac and dc magnetic fields in combination may affect binding equilibria of calcium-ions (Ca2+) was investigated with two metallochromic dyes as calcium-binding molecules: murexide and arsenazo III. Calcium-dye equilibria were followed by measuring solution absorbances with a fiber-optic spectrophotometer. A Ca(2+)-arsenazo solution(More)
In the biosynthesis of lincosamide antibiotics lincomycin and celesticetin, the amino acid and amino sugar units are linked by an amide bond. The respective condensing enzyme lincosamide synthetase (LS) is expected to be an unusual system combining nonribosomal peptide synthetase (NRPS) components with so far unknown amino sugar related activities. The(More)
who each inspired me to succeed for them in their own unique and special ways. Their support and sacrifice throughout this journey is immeasurable. iv ACKNOWLEDGEMENTS Words could not possibly express the absolute sincere appreciation I have for those who both supported and sacrificed so much during my pursuit for my graduate research and education. I would(More)
Structurally different and functionally diverse natural compounds - antitumour agents pyrrolo[1,4]benzodiazepines, bacterial hormone hormaomycin, and lincosamide antibiotic lincomycin - share a common building unit, 4-alkyl-L-proline derivative (APD). APDs arise from L-tyrosine through a special biosynthetic pathway. Its generally accepted scheme, however,(More)
The biosynthetic gene cluster of porothramycin, a sequence-selective DNA alkylating compound, was identified in the genome of producing strain Streptomyces albus subsp. albus (ATCC 39897) and sequentially characterized. A 39.7 kb long DNA region contains 27 putative genes, 18 of them revealing high similarity with homologous genes from biosynthetic gene(More)
The gene lmbB2 of the lincomycin biosynthetic gene cluster of Streptomyces lincolnensis ATCC 25466 was shown to code for an unusual tyrosine hydroxylating enzyme involved in the biosynthetic pathway of this clinically important antibiotic. LmbB2 was expressed in Escherichia coli, purified near to homogeneity and shown to convert tyrosine to(More)
Eukaryotic cells begin to assemble discrete, nucleoplasmic repair foci within seconds after the onset of exposure to ionizing radiation. Real-time imaging of this assembly has the potential to further our understanding of the effects of medical and environmental radiation exposure. Here, we describe a microirradiation system for targeted delivery of(More)
Chemical sensors for gases are at the forefront of the information acquisition chain about the environment in which we live. The quality of the air we breathe is one of the most important concerns of a modern society. A large number of gas sensors use conducting polymers (CPs) because they offer great design flexibility 1,2. They can form selective layers(More)
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