The impact of energy-related pollutants on chromosome structure: Final report, January 1, 1984-December 31, 1986

Technical Report · Thu Jan 01 04:00:00 EST 1987

OSTI ID:6020724

Rill, R L

Three projects are described. The structure of nucleosome cores was studied using chymotrypsin as a probe of hydrophobic residues accessible on the core surface showed that only leu-20 of H3 was readily accessible, although other core histones were ultimately cleaved. Primary sites of cleavage of H2a, H2b, and H4 were identified. Carbon-13 NMR spectroscopic methods were used to examine nucleosome cores and that about 10% of histone amino acid residues are contained in termini that are highly mobile. The major mobile segments were identified as amino terminal regions of H3 and H2a, plus a carboxy-terminal region of H2a. NMR studies of oligonucleosomes showed that these termini are not immobilized by binding to nucleosome linkers in certain higher order levels of chromatin structure. We have shown that nucleosome core length DNA forms cholesteric and other liquid crystalline phases at approximately physiological concentrations in simple saline solutions. Microscopic and NMR spectroscopic methods were used to identify liquid crystalline phases and to establish phase diagrams for transitions between phases as functions of DNA concentration and temperature. We have examined the sequence specificities of binding of bis-(o-phenanthroline) Cu(I) complex (CuOP), acetylacetoxyaminofluorene (AAAF), (+-)-anti-benzo(a)pyrene dihydrodiol epoxide (BPDE), methylene blue, and acridine orange to H3 and H2a genes. The first three chemicals bound non-randomly to DNA, while latter two bound nearly randomly. A preliminary map of binding sites of CuOP, AAAF, and BPDE in and near the H3 gene showed that several sequence regions were bound preferentially by two or more or these chemicals. CuOP appeared to exhibit the most specificity. All sites of high CuOP preference were also reactive towards AAAF and/or BPDE. 1 fig.

• Research Organization: Florida State Univ., Tallahassee (USA). Inst. of Molecular Biophysics
• DOE Contract Number: AS05-78EV05888
• OSTI ID: 6020724
• Report Number(s): DOE/EV/05888-T3; ON: DE87013056
• Country of Publication: United States
• Language: English

Related Subjects

550401 -- Genetics-- Tracer Techniques
560300* -- Chemicals Metabolism & Toxicology
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ACETYLAMINOFLUORENES
ACRIDINE ORANGE
ACRIDINES
ADDUCTS
AMINES
ANIMALS
AQUATIC ORGANISMS
AROMATICS
AUTORADIOGRAPHY
AZAARENES
AZINES
BENZOPYRENE
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOCHEMISTRY
BIOPHYSICS
CELL DIFFERENTIATION
CHEMISTRY
CHROMATIN
CONDENSED AROMATICS
DAYS LIVING RADIOISOTOPES
DNA
DNA ADDUCTS
DNA SEQUENCING
DYES
ECHINODERMS
EVEN-ODD NUCLEI
GENES
HETEROCYCLIC COMPOUNDS
HISTONES
HYDROCARBONS
INVERTEBRATES
ISOTOPES
LIGHT NUCLEI
MAGNETIC RESONANCE
MOLECULAR STRUCTURE
NUCLEAR MAGNETIC RESONANCE
NUCLEI
NUCLEIC ACIDS
NUCLEOPROTEINS
NUCLEOSOMES
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PHENANTHROLINES
PROTEIN STRUCTURE
PROTEINS
PYRIDINES
RADIOISOTOPES
RESONANCE
SEA URCHINS
STRUCTURAL CHEMICAL ANALYSIS
SULFUR 35
SULFUR ISOTOPES