title: [The resistance of the DNA of cyanophage LPP-3 to the action of different restriction endonucleases].
abstract: Data on the study of structure peculiarities of cyanophage LPP-3 DNA are presented in the work. The length of cyanophage DNA calculated by means of the enzymatic hydrolysis by restrictases is 40 +/- 3.5 thou. pairs of bases. Cyanophage LPP-3 DNA was hydrolysed by more than 50 different restrictases. As a result of screening it was found out that the great number of restrictases, which recognized hexanucleotide sequences did not hydrolyze DNA of cyanophage LPP-3. A considerable deviation of the number of the observed sites of restriction from their theoretically expected number for restrictases Hae III and Cfr 131 was established. Restrictases-isoschisomeres with different sensitivity to the methylation of the recognition sites--Msp I, Hpa II and Sau 3A, MboI and DpnI were used to check the availability of methylated bases in LPP-3 DNA. Absence of methylated adenine in the site GATC and methylated cytosine in the second position of the site CCGG were established. The results obtained permit supposing that the expressed counterselection by the sites of recognition of many restriction endonucleases takes place in cyanophage LPP-3 DNA. It is supposed that apparently, this method of protection of its genome in LPP-3 is one of most important but the inconsiderable percentage of site-specific methylation of the virus DNA cannot be completely excluded.
authors.forename: M I
authors.initials: MI
authors.lastname: Mendzhul
authors.forename: S A
authors.initials: SA
authors.lastname: Syrchin
authors.forename: B A
authors.initials: BA
authors.lastname: Rebentish
authors.forename: A A
authors.initials: AA
authors.lastname: Averkiev
authors.forename: I V
authors.initials: IV
authors.lastname: Busakhina
mesh_terms: D001435:Bacteriophages / Q000187:drug effects* / Q000235:genetics; D001483:Base Sequence; D000458:Cyanobacteria; D004262:DNA Restriction Enzymes / Q000494:pharmacology*; D004279:DNA, Viral / Q000032:analysis / Q000187:drug effects*; D004352:Drug Resistance, Microbial; D004587:Electrophoresis, Agar Gel; D006868:Hydrolysis; D008969:Molecular Sequence Data; D017862:Phycodnaviridae / Q000187:drug effects / Q000235:genetics; D015183:Restriction Mapping
chemical_list: D004279:DNA, Viral; D004262:DNA Restriction Enzymes
vernacular_title: Rezistentnost' DNK tsianofaga LPP-3 k deĭstviiu razlichnykh éndonukleaz restriktsii.