Wiktor Koźmiński

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The paper discusses glycosylation of trans-cinnamyl alcohol to obtain the biologically active compound rosavin and possibly other cinnamoylglycosides. Cell suspension cultures of Rhodiola rosea were established from callus of leaf origin cultured under light in a modified Murashige and Skoog medium. Under these conditions, no rosavin was formed. However,(More)
A new procedure for Fourier transform with respect to more than one time variable simultaneously is proposed for NMR data processing. In the case of two-dimensional transform the spectrum is calculated for pairs of frequencies, instead of conventional sequence of one-dimensional transforms. Therefore, it enables one to Fourier transform arbitrarily sampled(More)
Spectra obtained by application of multidimensional Fourier Transformation (MFT) to sparsely sampled nD NMR signals are usually corrupted due to missing data. In the present paper this phenomenon is investigated on simulations and experiments. An effective iterative algorithm for artifact suppression for sparse on-grid NMR data sets is discussed in detail.(More)
The characterization of intrinsically disordered proteins (IDPs) by NMR spectroscopy is made difficult by the extensive spectral overlaps. To overcome the intrinsic low-resolution of the spectra the introduction of high-dimensionality experiments is essential. We present here a set of high-resolution experiments based on direct (13)C-detection which proved(More)
A new, simple procedure is proposed which enables acquisition of two or more chemical shifts encoded in a common dimension simultaneously in quadrature. For n chemical shifts projected in a single dimension, the expected effect is obtained by interleaved acquisition and appropriate combination of 2(n) data sets per increment of respective evolution time.(More)
Chiral recognition by cyclodextrins is of considerable importance, especially for pharmaceutical industry, in view of the possible side effects of the second enantiometer of chiral drugs. In general, it manifests itself in all NMR parameters (chemical shifts, coupling constants, NOE and ROE effects, and relaxation rates) on one hand. On the other hand, it(More)
The aggregation of Zn(II)-bound and zinc-free human insulin was studied in solution using the H(beta)-CH(3) crosspeaks of threonine residues in 2D COSY, TOCSY, and NOESY NMR spectra which allow viewing of the oligomers in equilibrium. This is complemented by PFGSE measurements of the translational diffusion coefficient, D(i), used for monitoring the changes(More)
An ultra-high-resolution NMR experiment for the measurement of intraresidue (1)H(i)-(15)N(i)-(13)C'(i) dipolar-chemical shift anisotropy relaxation interference is employed to extract information about local backbone geometries in intrinsically disordered proteins. The study of tumor suppressor BASP1 revealed a population shift of β-turn geometries at low(More)
Recent developments in the acquisition and processing of NMR data sets facilitate the recording of ultra-high-resolution NMR spectra in a reasonable time. The new experiments allow easy resonance assignment for folded and unfolded proteins, as well as the precise determination of spectral parameters, for example, chemical shifts, NOE contacts, coupling(More)
A simplified phase-cycling scheme for heteronuclear active-coupling-pattern tilting (ACT) spectroscopy is presented. It is demonstrated that the theoretically expected twofold sensitivity gain over earlier implementations can be experimentally realized. A further intensity increase by a factor of 2 is obtained with standard sensitivity-enhancement(More)