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I Fodor

Publications and source records attributed to I Fodor.

110 records · Page 7Linked to original sources

[Structural organization of the genome of bacteriophage T5 by specific endonucleases].

The DNA of Bacteriophage T5+ has been treated with restriction endonucleases EcoRI, HindIII, BamI, SmaI, PstI, SalI, KpnI and the electrophorectic pattern obtained in agarose gel has been analyzed in order to localize the specific cleavage sites on the T5 DNA. The localization of cleavage sites has been resolved from the electrophoretic pattern of double and partial digests, the digests of isolated restriction fragments and the digests of deletion mutant T5 st(O) DNA. Four BamI cleavage sites have been found and localized on the physical map of T5 DNA at 0.225; 0.68; 0.715 and 0.725 fractional lenght. Endonuclease PstI cuts T5 DNA at 11 sites: 0.095; 0.215; 0.320; 0.510; 0.635; 0.675; 0.710; 0.770; 0.810; 0.840; 0.875 fractional length. Six KpnI cleavage sites have been mapped at 0.140; 0.160; 0.530; 0.720; 0.760; 0.840 fractional length. 14 out of 17 HindIII cleavage sites have been localized at 0.10; 0.24; 0.255; 0.345; 0.40; 0.52; 0.54; 0.57; 0.70; 0.76; 0.80; 0.84; 0.87; 0.89, fractional length of T5 DNA. Complete cleavage map of the phage genome is presented for seven restriction enzymes.

Coliphages↗

Effect of change in structure of cohesive ends on aggregating ability and biological activity of bacteriophage lambda DNA.

The effect of different types of buildup of the cohesive ends on the ability of phage lambda DNA molecules to form cyclic and concatemeric forms and on their biological activity in two infection systems--transfection and transformation--was investigated with the aid of E. coli DNA polymerase. A change in the structure of the cohesive ends leads to a change in the aggregating ability of the phage lambda DNA molecules up to an almost complete loss of this ability. The infectious activity of phage lambda DNA in the transfection system is very sensitive to a change in structure of the cohesive ends. It is suggested that phage development in this system requires retention of the ability to form cyclic or concatemeric forms. In the transformation system molecules with any of the modifications of the cohesive ends differ insignificantly from one another in infectivity. This can be attributed to the important role of recombination processes, which can save the defective DNA markers. DNAs with completely normal cohesive ends behave in the transformation system like phage lambda DNA fragments from internal parts of the molecule. No polarity of the cohesive ends is found when phage lambda develops in systems with or without a helper phage.

Base Sequence↗