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Biomedical subjects

R G Martin

Publications and source records attributed to R G Martin.

At least 163 records · Page 9Linked to original sources
PubMed1972

Characterization of an endonuclease associated with simian virus 40 virions.

An endonucleolytic activity associated with purified simian virus 40 (SV40) virions has been found. The enzyme is present in virions prepared from a number of different host lines. The enzyme is present in all early and late temperature-sensitive mutants examined. Some aspects of the endonucleolytic activity have been examined with SV40 deoxyribonucleic acid as substrate.

Animals↗
PubMed1972

Proposal for a uniform nomenclature for simian virus 40 mutants.

A uniform nomenclature for simian virus 40 mutants has been developed. This nomenclature should evolve into a comprehensive nomenclature as new mutants and information are obtained. Hopefully, his nomenclature will also stimulate the development of a comprehensive nomenclature for all animal virus mutants.

Genetic Complementation Test↗
PubMed1972

Genetic analysis of simian virus 40. 3. Characterization of a temperature-sensitive mutant blocked at an early stage of productive infection in monkey cells.

A temperature-sensitive mutant of simian virus 40 (SV40), ts(*)101, has been characterized during productive infection in monkey kidney cells. The mutant virion can adsorb to and penetrate the cell normally at the restrictive temperature, but cannot induce the synthesis of cellular deoxyribonucleic acid (DNA) nor initiate the synthesis of SV40-specific tumor, virion, or U antigens or viral DNA. First-cycle infection with purified ts(*)101 DNA is normal at the restrictive temperature, but the resulting progeny virions are still temperature-sensitive. The mutant neither complements nor inhibits other temperature-sensitive SV40 mutants or wild-type virions. The affected protein in the ts(*)101 mutant may be a regulatory structural protein, possibly a core protein, that is interacting with the viral DNA.

Adsorption↗
PubMed1971

Two mutations in the first gene of the histidine operon of Salmonella typhimurium affecting control.

Two strains with mutations in the first structural gene of the histidine operon of Salmonella typhimurium were characterized. (The first structural gene specifies the first enzyme of histidine biosynthesis, phosphoribosyltransferase, which is sensitive to feedback inhibition by histidine.) One mutation, hisG3934, results in a phosphoribosyltransferase which is no longer sensitive to feedback inhibition by histidine but is instead subject to inhibition by aspartic acid. The other mutation, hisG3935, allows the histidine operon to be partially repressed by several amino acids, including aspartic acid. Analysis of hisG3935 is consistent with the hypothesis that phosphoribosyltransferase is directly involved in the regulation of the histidine operon.

Amino Acids↗