[Effect of single-stranded DNA binding proteins on template/primer-independent DNA synthesis in the presence of nicking endonuclease Nt.BspD6I].

In the presence of the Nt.BspD6I nicking endonuclease DNA polymerase Bst stimulates intensive template/primer-independent DNA synthesis. Template/primer-independent DNA synthesis could be the reason for appearing nonspecific DNA products in many DNA amplification reactions particularly in the reactions with using nicking endonucleases.

[Late radiation effects in the microcirculation system of the mouse brain after chronic low-dose irradiation].

The radiation reaction of the mouse brain microvascular system was investigated 15 months after chronic (dose-rate was 3 cGy/day) and acute (dose-rate 3.2 Gy/min) gamma-irradiation. Late pathological changes in the microvascular system after the acute irradiation (3 Gy) were not found.

PCR fragmentation of DNA.

A method has been developed to prepare random DNA fragments using PCR. First, two cycles are carried out at 16 degrees C with the Klenow's fragment and oligonucleotides (random primers) with random 3'-sequences and the 5'-constant part containing the site for cloning with the site-specific endonuclease. The random primers can link to any DNA site, and random DNA fragments are formed during DNA synthesis.

Site-specific endonuclease NspLKI is an isoschizomer of endonuclease HaeIII.

Site-specific endonuclease NspLKI has been isolated and purified to functionally pure state from soil bacterium Nocardia species LK by successive chromatography on columns with phosphocellulose, HTP hydroxyapatite, and heparin-Sepharose. The isolated enzyme recognizes the 5'-GG downward arrowCC-3' sequence on DNA and cleaves it as indicated by the arrow, i.e.

A site-specific endonuclease from thermophilic strain Bacillus species ZE is a ClaI isoschizomer.

Strain Bacillus species ZE with a maximal yield of the ClaI isoschizomer was chosen from 12 natural thermophilic strains producing ClaI isomers. The yield is 110 times higher than that of the ClaI prototype endonuclease from Caryophanon latum L. The enzyme is sensitive to DNA dam-methylation and is highly stable under storage.