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Biomedical subjects

S W Fox

Publications and source records attributed to S W Fox.

85 records · Page 5Linked to original sources
PubMed1969

The condensation of the adenylates of the amino acids common to protein.

Simultaneous formation of the adenylates of the 18 amino acids common to protein, followed by cocondensation, has yielded polymers containing all of those amino acids. The condensation occurred rapidly at room temperature above pH 7. The activated amino acids were reacted with thermally synthesized polyanhydro-alpha-amino acids to yield polymers of substantially increased size. The modified polyamino acids form micron-sized particles which demonstrate internal synthesis by growth and budding. These particles are stable over a wide range of pH. From thermal polyamino acids alone, answers have earlier been obtained, in principle, to questions of the primordial origin of enzymes, cellular structure, membranes, systematic anhydroamino acid sequences, and propagation of microsystems. Such a model is largely heterotrophic; the mixed adenylate condensation provides, in principle, a partial answer to the origin of syntheses of peptide bonds within protocellular structures.

Adenine Nucleotides↗
PubMed1968

Melanocyte-stimulating hormone: activity in thermal polymers of alpha-amino acids.

Thermal polymers of arginine, glutamic acid, glycine, histidine, phenylalanine, and tryptophan have melanocyte-stimulating activity. The fact that similar polymers lack such activity indicates that the effect is related to the specific amino acid residues. The active polymers are discussed as a model of an evolutionary precursor of contemporary melanocyte-stimulating hormone.

Animals↗
PubMed1966

Simulation of organismic morphology and behavior by synthetic poly-alpha-amino acids.

Experiments imitating spontaneous geothermal occurrences have yielded most of the amino acids found in protein. All of the amino acids found in protein are simultaneously condensed, by heating in a range of appropriate conditions, to polymers which have many of the properties of proteins. These properties include molecular weights of many thousand, digestibility by proteolytic enzymes, and catalytic activities. One of the other properties is the tendency to form structured units; these units have many of the attributes of biocells. The processes indicated, and others, comprise a conceptual continuum which, according to accumulated information, must have occurred under the conditions existing in regions of the primitive Earth.

Amino Acids↗
PubMedDate not supplied

Effects of thermal peptides on retention of footshock avoidance training in mice.

Some hydrophobic polypeptides known as thermal proteins have been found to have neurotrophic effects. Thermal proteins were synthesized from aspartic acid, glutamic acid, proline, and tryptophan. Two hydrophobic and one nonhydrophobic polymers were injected intracerebroventricularly into brains of mice after partial training on footshock avoidance run in a T-maze. When retention was tested 1 week later, the hydrophobic polymers enhanced retention while the nonhydrophobic polymer did not. Thermal proteins exhibiting hydrophobicity and having neurotrophic effects may aid in altering synaptic connections by facilitating cell recognition.

Animals↗