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V Mackay

Publications and source records attributed to V Mackay.

7 recordsLinked to original sources
PubMed1976

Selective inhibition of the dnase activity of the recBC enzyme by the DNA binding protein from Escherichia coli.

In the presence of the Escherichia coli DNA binding protein, single-stranded DNA is resistant to both the endo- and exonucleolytic activities of the recBC DNase. Linear duplex DNA, on the other hand, is unwound at a normal rate, but converted to large, single-stranded fragments which are resistant to further hydrolysis. Therefore, in the presence of the binding protein and linear duplex DNA, the recBC enzyme acts not as a DNase, but primarily as an ATP-dependent unwinding enzyme, able to generate large, single-stranded material. Duplex circular DNA containing short, single-stranded gaps is also resistant to the hydrolysis in the presence of the binding protein.

Adenosine Triphosphate↗
PubMed1974

Molecular structure of exonuclease I from Escherichia coli B.

Exonuclease I of Escherichia coli B (EC 3.1.4.25) was determined to be a monomeric protein of molecular weight approx. 72,000, as estimated by Sephadex gel filtration, sedimentation velocity centrifugation, and sodium dodecylsulfate polyacrylamide gel electrophoresis.

Centrifugation, Density Gradient↗
PubMed1974

Mutations affecting sexual conjugation and related processes in Saccharomyces cerevisiae. I. Isolation and phenotypic characterization of nonmating mutants.

Nonmating mutants were also isolated from haploid strains of yeast of both mating types. The mutants were characterized with respect to their ability to produce and respond to specific yeast sex factors, their ability to mate at low frequencies, and the ability of the low-frequency diploids to sporulate. Loss of the ability to mate by either mating type was invariably accompanied by the loss of one or more, and in some cases, all, of the above capabilities. The results strongly indicate that the sex factors are functionally involved in the conjugation process.

Alleles↗
PubMed1974

Mutations affecting sexual conjugation and related processes in Saccharomyces cerevisiae. II. Genetic analysis of nonmating mutants.

Rare diploids formed by sterile mutants have been studied by tetrad analysis. Sixteen classes of mutants representing at least five distinct genetic loci have been defined. One group of mutations, isolated only in alpha, maps at the mating-type locus, while none of the others shows any linkage to mating type. Some of the mutations are nonspecific for mating type, while others act only on a or alpha. In addition, mutations were found that prevent sporulation when heterozygous in diploids. These appear to be mutations of the mating-type alleles.

Alleles↗