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L C Hayes

Publications and source records attributed to L C Hayes.

10 recordsLinked to original sources
PubMed1992

Reduction-driven polypeptide folding by the delta Tt mechanism.

Poly(Gly-Val-Gly-Val-Pro), i.e., poly(GVGVP), exhibits composition and solute dependence of Tt, the temperature of the inverse temperature transition at which hydrophobic folding and assembly occur on raising the temperature. Importantly, a means whereby the value of Tt is lowered from above to below the working temperature becomes an isothermal means of driving folding and assembly, i.e., of achieving free energy transduction. Using poly[0.73(GVGVP),0.27(GK[NMeN]GVP)] where [NMeN] indicates N-methyl nicotinamide attached to the epsilon-NH2 of the Lys(K) residue, chemical and electrochemical reductions are found to remarkably lower the value of Tt; reduction can drive hydrophobic folding and assembly as effectively as decreasing ionization. Changing the redox state of a protein becomes yet another means of achieving free energy transduction by the delta Tt mechanism.

Amino Acid Sequence↗
PubMed1977

Adsorption of messenger RNA of Novikoff hepatoma, normal liver, and regenerating liver on complementary DNA-cellulose affinity matrices.

Complementary DNA (cDNA)-oligodeoxythmidylate-celluloses were prepared from cDNA copies of polysomal messenger RNA (mRNA) of Novikoff hepatoma, normal rat liver, and regenerating rat liver. cDNA synthesis with reverse transcriptase was approximately 46% with respect to input mRNA with oligodeoxythymidylate-cellulose primer. The cDNA's of normal liver, regenerating liver, and Novikoff hepatomas were used as affinity matrices for hybridization of different mRNA species. Under the conditions used, degradation of mRNA was not detected. After normalization for homologous hybridization efficiency, 53 and 65% of the Novikoff hepatoma mRNA bound to normal liver and regenerating liver cDNA's. Under these conditions an average of 82% of mRNA of normal liver bound to regenerating liver cDNA, and 92% of regenerating liver mRNA bound to normal liver cDNA. The bound and unbound mRNA's were analyzed by translation in the wheat germ system; 2-D gel analysis of the proteins synthesized in the wheat germ system indicated that the cDNA affinity columns selectively adsorbed some mRNA species.

Animals↗
PubMed1976

Electrophoresis of human multiple myeloma and Waldenström's macroglobulinemia sera in sodium dodecyl sulfate polyacrylamide gels.

Sera from normal persons and patients with IgA, IgD, IgG, and IgM monoclonal gammopathies were electrophoresed in polyacrylamide gels containing sodium dodecyl sulfate. The gels were stained with Coomassie blue or were used for immunodiffusion. By this method IgG multiple myeloma and IgM Waldenström's macroglobulinemia sera were readily distinguished by electrophoresis alone, whereas IgA and IgD myeloma sera were distinguished by further immunodiffusion against anti-alpha-chain antibody and anti-delta-chain antibody.

Electrophoresis, Polyacrylamide Gel↗
PubMed1975

Characterization of monosomes produced by aflatoxin B1.

A single injection of 1.5 mg aflatoxin B1 per kg body weight produced approx. 70% disaggregation of rat liver polysomes into monosomes within 18 h. Isolated monosomes dissociated into 40 S subunits during centrifugation in linear sucrose gradients containing 0.3 M KCI. The 4 S to 5 S molar RNA ratio of the monosomes was calculated to be 0.6, indicating 0.6 tRNA and/or aminoacyl tRNA molecule per ribosome; no peptidyl tRNA was present. These results suggest that a single injection of affatoxin B1 produces monosomes which resemble runoff ribosomes.

Aflatoxins↗