The initial step in the infectious cycle of the single-stranded DNA phage øX174 is the synthesis of a DNA strand complementary to the infecting viral DNA producing a duplex molecule, the parental replicative form (RF). Electron micrographic examination of parental RF produced from viruses exposed to ultra-violet (UV) light suggests that synthesis begins at only one site. However, in vitro results and some recent reports of in vivo experiements contradict that interpretation.
Using restriction enzymes we have re-examined the incomplete RF made from UV-damaged phage. Parental RF made in vivo from viruses exposed to various UV doses were purified by velocity sedimentation and benzoylated naphthoylated diethylaminoethylcellulose column chromatography. The incomplete parental RF were digested with a restriction enzyme and the fragments separated by by gel electrophoresis. The genetic location of the new DNA was determined from the relative amount of label appearing at each fragment position.
Readioactive label was not uniformly distributed among the DNA fragments, but neither was there a simple sequence of increasing radioactivity. We conclude that initiation was not random but occurred at several sites. The data do not exclude the possibility that a single initiation site was employed on each template but that the site varied from template to template.
","abstract_html":"<p>The initial step in the infectious cycle of the single-stranded DNA phage øX174 is the synthesis of a DNA strand complementary to the infecting viral DNA producing a duplex molecule, the parental replicative form (RF). Electron micrographic examination of parental RF produced from viruses exposed to ultra-violet (UV) light suggests that synthesis begins at only one site. However, <em>in vitro</em> results and some recent reports of <em>in vivo</em> experiements contradict that interpretation.</p> <p>Using restriction enzymes we have re-examined the incomplete RF made from UV-damaged phage. Parental RF made <em>in vivo</em> from viruses exposed to various UV doses were purified by velocity sedimentation and benzoylated naphthoylated diethylaminoethylcellulose column chromatography. The incomplete parental RF were digested with a restriction enzyme and the fragments separated by by gel electrophoresis. The genetic location of the new DNA was determined from the relative amount of label appearing at each fragment position.</p> <p>Readioactive label was not uniformly distributed among the DNA fragments, but neither was there a simple sequence of increasing radioactivity. We conclude that initiation was not random but occurred at several sites. The data do not exclude the possibility that a single initiation site was employed on each template but that the site varied from template to template.</p>","abstract_has_math":false,"creators":["Bogardus, Alicia Morales"],"institution":null,"degree_name":"Master of Arts (MA)","degree_level":"Thesis","degree_discipline":"Biology","degree_department":null,"school":null,"contributors":["Anthony J. Zuccarelli","Leonard R. Brand","Robert L. Nutter"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":1979,"date_issued":"1979-08-01T07:00:00Z","date_published":"1979-08-01T07:00:00Z","updated_at":"2026-07-24T02:53:44Z","subjects":["Biology","Bacteriophages -- analysis; DNA Restriction Enzymes; DNA Single-Stranded"],"languages":["English"],"rights":["This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights."],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://scholarsrepository.llu.edu/etd/1396","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Anthony J. Zuccarelli","Leonard R. Brand","Robert L. Nutter"]},{"key":"dc:creator","label":"Author","values":["Bogardus, Alicia Morales"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"thesis:degree_discipline","label":"Discipline","values":["Biology"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Arts (MA)"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Biology","Bacteriophages -- analysis; DNA Restriction Enzymes; DNA Single-Stranded"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["English"]},{"key":"dc:rights","label":"Dc Rights","values":["This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://scholarsrepository.llu.edu/etd/1396"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["The initial step in the infectious cycle of the single-stranded DNA phage øX174 is the synthesis of a DNA strand complementary to the infecting viral DNA producing a duplex molecule, the parental replicative form (RF). Electron micrographic examination of parental RF produced from viruses exposed to ultra-violet (UV) light suggests that synthesis begins at only one site. However, in vitro results and some recent reports of in vivo experiements contradict that interpretation.
Using restriction enzymes we have re-examined the incomplete RF made from UV-damaged phage. Parental RF made in vivo from viruses exposed to various UV doses were purified by velocity sedimentation and benzoylated naphthoylated diethylaminoethylcellulose column chromatography. The incomplete parental RF were digested with a restriction enzyme and the fragments separated by by gel electrophoresis. The genetic location of the new DNA was determined from the relative amount of label appearing at each fragment position.
Readioactive label was not uniformly distributed among the DNA fragments, but neither was there a simple sequence of increasing radioactivity. We conclude that initiation was not random but occurred at several sites. The data do not exclude the possibility that a single initiation site was employed on each template but that the site varied from template to template.
"]},{"key":"dc:title","label":"Title","values":["Restriction Enzyme Analysis of Incomplete Parental Replicative Forms of øX174"]}]}],"canonical_facts":{"dc:contributor":["Anthony J. Zuccarelli","Leonard R. Brand","Robert L. Nutter"],"dc:creator":["Bogardus, Alicia Morales"],"dc:description.abstract":["The initial step in the infectious cycle of the single-stranded DNA phage øX174 is the synthesis of a DNA strand complementary to the infecting viral DNA producing a duplex molecule, the parental replicative form (RF). Electron micrographic examination of parental RF produced from viruses exposed to ultra-violet (UV) light suggests that synthesis begins at only one site. However, in vitro results and some recent reports of in vivo experiements contradict that interpretation.
Using restriction enzymes we have re-examined the incomplete RF made from UV-damaged phage. Parental RF made in vivo from viruses exposed to various UV doses were purified by velocity sedimentation and benzoylated naphthoylated diethylaminoethylcellulose column chromatography. The incomplete parental RF were digested with a restriction enzyme and the fragments separated by by gel electrophoresis. The genetic location of the new DNA was determined from the relative amount of label appearing at each fragment position.
Readioactive label was not uniformly distributed among the DNA fragments, but neither was there a simple sequence of increasing radioactivity. We conclude that initiation was not random but occurred at several sites. The data do not exclude the possibility that a single initiation site was employed on each template but that the site varied from template to template.
"],"dc:identifier":["https://scholarsrepository.llu.edu/etd/1396"],"dc:language":["English"],"dc:rights":["This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights."],"dc:subject":["Biology","Bacteriophages -- analysis; DNA Restriction Enzymes; DNA Single-Stranded"],"dc:title":["Restriction Enzyme Analysis of Incomplete Parental Replicative Forms of øX174"],"thesis:degree_discipline":["Biology"],"thesis:degree_level":["Thesis"],"thesis:degree_name":["Master of Arts (MA)"]},"updated_at":"2026-07-24T02:53:44Z"}