Molecular basis for the mutagenic and lethal effects of ultraviolet irradiation. Research accomplishments (1968 to present)

Technical Report · Sun Jan 01 04:00:00 EST 1978

DOI:https://doi.org/10.2172/5638293· OSTI ID:5638293

Grossman, L

Earlier work on the chemical basis of mutagenesis led to certain chemical generalities sufficient to explain how certain mutagens such as uv light and hydroxylamine functioned in information transfer systems (replicative, transcriptive and translational). When such modifications were applied to biologically active DNA in a controlled manner biological expression was non-stoichiometric because much of the damage was removed from the DNA by repair systems. Our efforts were then directed to these systems which led to: (1) the isolation, purification and characterization of endonucleases responsible for the first and controlling step in DNA repair - referred to as incision in both M. luteus and E. coli. The biological role of these enzymes was inferred in appropriate mutants; (2) the isolation, purification and characterization of exonucleases responsible for the removal or excision of damaged nucleotides in M. luteus and human placental trophoblasts; (3) the repair of uv damaged biologically active transforming and transfecting DNAs by purified endonucleases, exonucleases, DNA polymerase I and polynucleotide ligase from M. luteus and E. coli; (4) the characterization of the dual gene control for incision phenomenon in M. luteus and E. coli; and (5) isolation, purification and characterization of repair enzymes from human placenta (currently in progress).

• Research Organization: Johns Hopkins Univ., Baltimore, MD (USA). Dept. of Biochemistry
• OSTI ID: 5638293
• Report Number(s): COO-2814-5
• Country of Publication: United States
• Language: English

Related Subjects

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63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
BIOLOGICAL RECOVERY
BIOLOGICAL REPAIR
DNA
ELECTROMAGNETIC RADIATION
ENZYMES
GENETIC EFFECTS
GENETIC RADIATION EFFECTS
NUCLEASES
NUCLEIC ACIDS
ORGANIC COMPOUNDS
PHOSPHOTRANSFERASES
PURIFICATION
RADIATION EFFECTS
RADIATIONS
RECOVERY
REPAIR
TRANSFERASES
ULTRAVIOLET RADIATION