The DNAs (deoxyribonucleic acids)
of the thoracic tissue
of
the tobacco hornworm,
Manducta sexta, were studied
by physical
and chemical means. The adult
moth was considered to
be fully
formed two days after emergence from
the pupal case, as indicated
by its ability to fly and the integrity
of the...
Investigators have been studying an aggregate
containing enzymes of deoxyribonucleoside triphosphate
biosynthesis in T4-phage infected bacteria. They suggest
that it behaves as an organized complex, efficiently
channeling DNA precursors to the replication apparatus.
Previous work has suggested that about 10 enzyme
activities remain associated through several fractionation
steps. This multi-enzyme...
The genome composition and DNA base sequence homologies
of several diverse species of fish were examined. The fishes were
characterized from spectrophotometric studies of reassociation and
hybridization of their DNAs and from the thermal stabilities of hybrid
duplexes.
Spectrophotometric studies indicated that repeated sequences
comprise 35-40% of the genomes of...
DNA four-way junctions (also known as Holliday junctions) are the primary structural intermediate during recombination, an important process responsible for biological evolution and maintenance of genomes. These junctions arise from the assembly of four nucleic acid strands to produce double-helical regions extending from a central point. Although much progress has...
Using thermal denaturation methodology, the nucleic acid
base composition of deoxyribonucleic acid (DNA) isolated from type,
neotype and stock strains of Lactobacillus species was determined.
The genus was found to be heterogeneous in base composition,
ranging from 33.1 to 50.0 moles % guanine plus cytosine (GC).
Genus members fell into...
This dissertation describes an investigation of DNA precursor supply for mitochondrial and nuclear DNA synthesis in HeLa cells and Mouse L-cells. HeLa cells were used for the quantitation of cellular and mitochondrial deoxyribonucleoside triphosphate (dNTP) and ribonucleoside triphosphate (rNTP) pools and of changes in pools in response to treatment with...
The aim of this study was to gain more information about the
interactions between DNA and the histone octamer during the
process of transcription. This work used a pUC8 plasmid derivative
that contained the core promoter region of the RNA polymerase I of
Acanthamoeba castellanii, placed upstream of four repeats...
The genome of the nuclear polyhedrosis virus which infects the
larvae of the tussock moth, the lepidopteran, Hemerocampa
pseudotsugata, was isolated, identified as deoxyribonucleic acid, and
characterized in terms of its physical and biological properties. An
isolation procedure for the viral DNA was established which consisted
of the following steps:...
Work is presented which explores the properties and nature of
the P-form of DNA. Initially the P-form represented an unknown
state of DNA which occurred when this molecule was in a solvent of
47.5% methanol, 5% water, and 47.5% ethanol, and which showed properties
of both native and denatured conformations....
The question of how the presence of nucleosomal
packing of DNA modifies carcinogen interaction at
specific sites cannot be answered by studies on whole
chromatin or bulk nucleosomes because of the
heterogeneity of DNA sequences in the particles. This
problem was circumvented by constructing nucleosomes that
are homogenous in DNA-histone...
The studies presented here use the B- to Z-DNA transition and Z-DNA
crystallization as model systems to determine the contribution of solvent interactions to
macromolecular structures. The substituent groups of naturally occurring and modified
nucleotide bases affect the hydration and thus the stability of right-handed B-DNA and
left-handed Z-DNA. The...
The interaction of polylysine with DNA may be divided into two
separate phenomena: the primary interaction involved in formation of
a well-defined complex, and secondary interactions leading to aggregation
of these complexes. Most studies on the interaction of polylysine
with DNA have used techniques which measure properties of
the aggregated...
The association of other materials with DNA has been studied
extensively in higher organisms and more recently in bacteria.
However, investigation of these complexes in bacteria have for the
most part been restricted to the study of a specific function this association
may serve, or a specific kind of association....