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A D Gruzdev

Publications and source records attributed to A D Gruzdev.

At least 37 records · Page 2Linked to original sources
PubMedDate not supplied

[Structure of virions of the M13 phage containing chimeric B-protein molecules].

We have studied the virion structure of M13 strains (M13B1, M13BOM1, M13BOM2, M13BOL1) with chimeric variants of B-protein. Data concerning the spatial structure of chimeric B-protein molecules and their interaction with intraphage DNA were obtained. The phage contour lengths were measured under electron microscope and the DNA/protein ratios were obtained by spectrophotometry. These data testified that the insertion of foreign peptide affected neither DNA packaging nor the compactness of molecular arrangement of proteins in the virion. By linear dichroism and fluorescence spectra of phages it was determined, that the insert can influence the polarity of amino acid environment and the orientation of amino acids in the B-protein central part. It was shown by quenching of phage fluorescence by KI that the inward or outward amino acids location in the capsid is invariable. The carboxyl residues have been titrated in the phage strains by Auramine O. It was shown that there is no correlation between the number of the titrated carboxyl groups and the number of the carboxyl groups as a whole.

Amino Acid Sequence↗
PubMedDate not supplied

[Effect of the length of internucleosome regions of DNA on the conformation of chromatid fibrils].

Models of chromatin fibers structures with linear regions of linker DNA were analysed. Limitations put by end dimensions of linker DNA and nucleosomes are considered. Good agreement between the structural properties of model and real chromatin fibers was obtained. It has been shown that the models with three and more configurations of closely located nucleosomes have linker DNA of 19-53 base pairs length, which is characteristic of real chromatin of the majority of somatic cells.

Chromatin↗
PubMedDate not supplied

[DNA packing in the DNP fibrils of polytene chromosomes].

Isolated polytene chromosomes stained with acridine orange were stretched with micromanipulator needles. Changes of chromosome fluorescence polarization led to the conclusions: 1) almost complete orientation of DNP fibers is attained at very low levels of chromosome stretching (3--8 times) without irreversible disruption of chromomeres; 2) internucleosomal DNA in native DNP fibers is supercoiled and makes 30 degrees angle to the fiber axis.

Acridines↗