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J W Preiss

Publications and source records attributed to J W Preiss.

11 recordsLinked to original sources
PubMed1976

Protein-polynucleotide scattering centers as a protein structure probe.

When certain basic globular proteins are mixed with nucleic acids near a critical concentration ratio, large, low density scattering centers of about 10(9) particle weight are created. Scattering from these complexes is altered when thermally inactivated proteins are substituted for enzymes in their native, globular conformation. Scattering data from heat-treated ribonuclease and lysozyme mixed with four different synthetic homopolyribonucleotides are reported. The concentration of nucleic acid necessary to produce maximum scattering from a heat-treated protein sample is shown to be a direct indication of the amount of enzyme that remains biologically active after being heated.

Light↗
PubMed1973

Temperature variation of polyribonucleotide conformation by an interaction with basic globular proteins.

Chicken lysozyme interacts with polyribonucleotides to form large light-scattering centers. The size of these is critically dependent on conformation of the polynucleotides. Hence, the interaction provides a very sensitive method of determining temperature intervals within which the polynucleotides change from multistranded, stacked-base structures to single-stranded, random coils. This change can be observed with the unaided eye, especially when concentrations of polynucleotides are of the order of a few micrograms per milliliter.

Adenine Nucleotides↗
PubMed1972

Some parallelisms n the behavior of pancreatic ribonuclease and chicken lysozyme toward homopolyribonucleotides.

Pancreatic ribonuclease and chicken lysozyme possess gross similarities that are responsible for a common ability to form enormous light-scattering centers in cooperation with homopolyribonucleotides. The light-scattering power of the mixtures is highest when [homopolymer]/[protein] assumes some critical value that is unique for each homopolymer-protein pair. In some respects the scatterers resemble very large antigen-antibody networks. A criterion is established to ascertain the relative abilities of the homopolymers to form the centers with the two proteins. Both see polyinosinic acid (poly-I) as most and polyadenylic acid (poly-A) as least efficient in this respect.

Adenine Nucleotides↗
PubMed1969

Pancreatic ribonuclease-poly G complexes: complete inhibition of poly U hydrolysis.

Pancreatic ribonuclease forms large complexes with poly G in 0.1 M acetate buffer solutions (pH 5.4). These are largest when the ratio, of ribonuclease to poly G concentration, is slightly less than 2. Under the same conditions lysozyme forms still larger complexes with poly U, and these are largest when the ratio, of lysozyme to poly U concentration, is about 2.5. The ribonuclease in ribonuclease-poly G complexes digests poly U. Free ribonuclease digests the poly U in lysozyme-poly U complexes. However, when the poly G concentration is about an order of magnitude greater than that required to bind all the ribonuclease, lysozyme-bound poly U is not hydrolyzed.

Acetates↗
PubMed1968

Dynamics of the interactions of basic proteins with polyribonucleotides.

Pancreatic ribonuclease was irradiated in the dried state with electrons and then added to acetate buffer solutions that contained different concentrations of polyribonucleotides. Qualitatively similar results were obtained by adding a combination of unirradiated ribonuclease and lysozyme to such solutions. Such solutions scatter light strongly, and the intensity of the scattered light changes with time after mixing. The angular distribution of the scattered light was obtained as a function of time and compared with the rates at which hydrolysis products were formed. The turbidity of the solutions increases rapidly with time at the lower polyribonucleotide concentrations, and seems to result from a complex between inactive ribonuclease, or lysozyme, and oligonucleotides that appear during enzymic hydrolysis of the polynucleotides. The dissymmetry of the scattered light is approximately 5, indicating that the scattering centers are, if spherical, about 1500 A in diameter. The turbidities are remarkably high when one considers the low concentrations of protein and nucleic acid materials that are used.

Adenine Nucleotides↗
PubMed1968

The complexing of lysozyme with poly C and other homopolymers.

Lysozyme forms very large complexes with poly C, in acetate buffer solutions (pH 5.4), when the ratio of lysozyme to poly C concentration is 3/2. When this is less than 3/8 there is virtually no complexing, as evidenced by the low light-scattering power of such mixtures. At such relatively high poly C concentrations, the addition of pancreatic ribonuclease causes both the intensity and dissymmetry of scattering to rise to very high values after which time the intensity falls exponentially with time and with very little change in dissymmetry. Other homopolymers also form largest complexes with lysozyme at characteristic concentration ratios.

Adenine Nucleotides↗