Showing papers in "Journal of Molecular Biology in 1969"

TL;DR: Intercistronic complementation was observed between three classes of restriction and modification mutants of E. coli B, indicating that at least three cistron (the ram cistrons) are involved in the genetic control of the [restriction and modification of DNA].

TL;DR: Under suitable experimental conditions, low concentrations of papain can split the enzymic globular regions of myosin from the structural α-helical rod, leaving the latter intact along its length.

TL;DR: The biochemical evidence shows that the role of α-lactalbumin in the synthesis of lactose is a complex one requiring direct interaction with the A protein.

TL;DR: A rapid refinement procedure capable of deriving the stable conformation of a macromolecule from experimental model co-ordinates is presented and a set of non-bonded potential functions applicable to the equilibrium of a folded protein in an aqueous medium is described and tested on myoglobin.

TL;DR: Bacterial polyribosomes, ribosomes and ribosomal subunits were found to possess characteristic electrophoretic mobilities in polyacrylamide-agarose composite gels and it is likely that some of the variations in subunit mobilities are related to differences in the size of the RNA which they contain.

TL;DR: It is concluded that the modification of the base adjacent to the anticodon in tyrosine transfer RNA is essential for its efficient binding to ribosomes, but not for itsefficient charging.

TL;DR: A detailed analysis of the binding of N-formyl-l-tryptophan to the active site of α-chymotrypsin shows that the indolyl side chain lies in a hydrophobic pocket or slit, which accounts for the specificity of this enzyme for binding arginine or lysine side chains.

TL;DR: By localizing the site of action of murein hydrolases which are directly involved in bacterial morphogenesis, this structural element of the cell wall is enlarged exactly as predicted by the replicon hypothesis.

TL;DR: It is shown that when chromosomal proteins, principally histones, are dissociated from DNA by 2 m -NaCl and then reassociated by gradient dialysis to low ionic strength, the original chromatin is not reconstituted, but reconstitution by gradientdialysis in the presence of 5 m -urea does result in chromatin equivalent to native by the hybridization-competition criterion.

TL;DR: In this paper, two polysaccharides have been studied which approximate in structure to alternating copolymers, (−A−B) n, in which B is a residue of β-d -galactose-4sulphate and A is an anhydrous residue of 3,6-anhydro-α-d-galactoses (κ-carrageenan).

TL;DR: The dimensions of the mixed lipidic layers and that of the intercalated layers of water have thus been determined as a function of the percentage of the different components of this ternary system.

TL;DR: An early function in translation is shown to be rate limiting at the elevated temperature and is the cause of polyribosome disaggregation and an RNA factor is produced which appears to promote the association of ribosomes with messenger RNA.

TL;DR: The synthesis of RNA associated with the mitochondria of HeLa cells is selectively inhibited by relatively low concentrations of ethidium bromide, and the ethidiumsensitive RNA does not appear on membrane-associated polyribosomes.

TL;DR: Temperature-jump relaxation kinetic studies of the proflavine-DNA complex indicate that there are two forms of the complex at equilibrium, and evidence is presented for the view that in the less strongly bound form the dye is attached externally to the double helix, and that this outside binding precedes insertion in the intercalation reaction.

TL;DR: The kinetics of this refolding process under the conditions used has been shown to be almost identical to those of reconstitution of 30 s ribosomes from RNA and proteins, representing a structural rearrangement of RI particles which requires high activation energy.

TL;DR: There is a specific polar end-to-end bonding of tropomyosin molecules which defines the period of about 400 A observed in the polymorphic nets and tactoids; there are two cross-connecting sites which are involved in net formation; in many of the forms, the polar filaments are arranged in oppositely directed pairs; the molecular coiled-coil is often supercoiled in the polar Filaments.

TL;DR: Ambiguity caused by ram, by streptomycin and by their combination is antagonized in vivo and in vitro by additional mutations at the strA locus, which restricts ribosomal suppression and returns to normal the reduced growth rate produced by ram mutation in a wild-type strA+ strain.

TL;DR: Changes in hydration are likely to have an important role in effects observed at high concentrations of the added substance, as well as from changes in the extent of binding of theadded substance.

TL;DR: The possible function of the protein-bound RNA in chick embryo chromatin is examined by experiments involving chromatin reconstitution and DNA-RNA hybridization of the template products.

TL;DR: It is infer that the complex comprises the specific portion of the cell membrane to which the DNA is attached within the cell, and this complex depends on the interaction of cell membrane components with the crystals of detergent.

TL;DR: These experiments show that one structural component of the rod outer segment disc membranes, the visual pigment apoprotein, is constantly renewed, and a model for the synthesis and assembly of rod outer segments disc membranes is proposed.

TL;DR: It appears that the l-sites are primarily involved in the regulation of the over-all activity of the enzyme, while binding of effectors to the h-sites influences the substrate-specificity of ribonucleoside diphosphate reductase.

TL;DR: In this article, the number of 4, 18 and 26 s RNA cistrons present in purified nuclear and mitochondrial DNA of Saccharomyces cerevisiae has been determined and the significance of these findings to the continuous synthesis of ribosomal RNA during the cell cycle of yeast is discussed.

TL;DR: Studies on cyclic bacteriophage λb2b5c DNA covalently closed in vitro by Escherichia coli polynucleotide joining enzyme reveal the following: the DNA helix unwinds slightly as the temperature is increased at temperatures 60 to 100 deg.

TL;DR: Growing cultures of Escherichia coli and Salmonella typhimurium excreted lipopolysaecharide, phospholipid and protein into the culture fluid when protein synthesis was inhibited, and the excretion appears to be a membrane complex arising from the outer membrane of the cell envelope.

TL;DR: Density-gradient analysis shows that λ transducing phages which carry spontaneous extreme polar mutations of the galactose operon have higher buoyant densities than otherwise identical phage which carry a wild-type galactoses operon.

TL;DR: It is found that less than 1 in 60,000 complementary molecules in RNA from liver, spleen or kidney cells may not be transcribed, and it should be easy to detect RNA which is complementary to one or the other of the highly reiterated sequences in the light or heavy strands.

TL;DR: It appears from data that release of aminoacyl-tRNA is the rate-limiting step in the acylation, or transfer, reaction.

TL;DR: This finding suggests that R-factors continue to replicate for several hours during the stationary phase of growth, which is consistent with a model in which individual copies of the R-factor are selected at random for replication without discrimination as to whether any particular copy has been duplicated one or more times during that generation.