title: [Protection of segments of replicative form I of phiX174 phage DNA recognized by HindII, BspRI, and AluI restrictases by Escherichia coli RNA-polymerase].
abstract: The preincubation of a DNA with E. coli RNA polymerase provides its partial protection against the HindII, BspRI and AluI cleavage giving possibility to determine the location of RNA polymerase tight-binding sites. Using this approach about 16 RNA polymerase tight-binding sites were detected on replicative form of phiX174 phage DNA. The protection degree of each of these sites depended on the preincubation conditions. Some of the protected sites hit the known phiX174 promoters and rho-dependent terminators and the other were distributed along the whole phiX174 DNA molecule. Many of them could be considered as potential promoters because they contain all the necessary elements specifying the real promoter sequences. At least some of the intrinsic promoter elements could be observed next to the rest of protected sites. One of the protected sites (R6b/l) is located in phiX174 DNA region which is very similar to the cAMP-CRP-controlled promoter sequences. It was confirmed that phiX174 DNA has two B promoters positioned by Sanger on the phiX174 nucleotide map, according to our data obtained by RNA polymerase protection experiments along with RNA product analysis of the R8 DNA fragment transcription in vitro.
mesh_terms: D010584:Bacteriophage phi X 174 / Q000378:metabolism*; D001665:Binding Sites; D002384:Catalysis; D004262:DNA Restriction Enzymes / Q000378:metabolism*; D004279:DNA, Viral / Q000378:metabolism*; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism*; D015252:Deoxyribonucleases, Type II Site-Specific; D004926:Escherichia coli / Q000201:enzymology*
chemical_list: D004279:DNA, Viral; D012321:DNA-Directed RNA Polymerases; D004262:DNA Restriction Enzymes; C024669:endodeoxyribonuclease AluI; C024402:endodeoxyribonuclease Bsp; D015252:Deoxyribonucleases, Type II Site-Specific; C024400:GTYRAC-specific type II deoxyribonucleases
vernacular_title: Zashchita RNK-polimerazoĭ Escherichia coli uchastkov replikativnoĭ formy I DNK faga phiX174, uznavaemykh restriktazami HindII, BspRI i AluI.