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Biomedical subjects

N C Brown

Publications and source records attributed to N C Brown.

At least 73 records · Page 4Linked to original sources
PubMed1972

Morphology and physical properties of Staphylococcus bacteriophage P11-M15.

The Group B Staphylococcus phage P11-M15 is shown to be 51% protein and 49% deoxyribonucleic acid (DNA). The intact virion has a molecular weight of 66.7 x 10(6) daltons. The purified viral DNA has a molecular weight of 32.7 x 10(6) daltons. The intact virion is shown to be composed of a polyhedral head which is attached at one of its vertices to a flexible tail having helical symmetry. The tail structure is terminated by a complex baseplate which has sixfold symmetry. The virion contains a single molecule of double-stranded DNA which has no apparent single-strand nicks or single-stranded terminal redundancies.

Centrifugation, Density Gradient↗
PubMed1971

6(p-Hydroxyphenylazo)-uracil: a reversible, selective inhibitor of the replication of deoxyribonucleic acid of staphylococcal bacteriophage P11-M15.

6(p-Hydroxyphenylazo)-uracil (HPUra), a selective inhibitor of the semiconservative replication of deoxyribonucleic acid (DNA) of gram-positive bacteria, was found to inhibit the replication of DNA of bacteriophage P11-M15, a virulent derivative of the temperate Staphylococcus aureus bacteriophage P11. At appropriate concentration, HPUra inhibited DNA synthesis by P11-M15-infected S. aureus immediately and completely, regardless of the stage of the lytic cycle at which infected cells were exposed to drug. The effect of HPUra was reversible since the capacity of inhibited, infected cells to replicate phage DNA and produce mature phage could be restored by removal of HPUra from incubation media. Concentrations of HPUra which completely inhibited the replication of P11-M15 in its drug-sensitive host did not inhibit the replication of this phage or its DNA in several drug-resistant host mutants. HPUra also did not inhibit the replication of two other serologically distinct, virulent staphylococcal bacteriophages, P1 and 44AHJD, in drug-sensitive hosts.

Adenine↗
PubMed1970

6-(p-hydroxyphenylazo)-uracil: a selective inhibitor of host DNA replication in phage-infected Bacillus subtilis.

The azopyrimidine, 6-(p-hydroxyphenylazo)-uracil, inhibits the replication of bacterial DNA selectively, completely, and reversibly, and has no apparent effects on the metabolism of other cellular macromolecules thus far examined. The mechanism of its action has been investigated in uninfected and phage-infected Bacillus subtilis, and the compound appears to be specific for a host function. In cells infected with virulent phage the synthesis of phage DNA proceeds normally, while residual host DNA synthesis is completely blocked. The drug-sensitive host site retains its sensitivity even after partial disruption of the cell by lysozyme treatment.

Azo Compounds↗
PubMedDate not supplied

Construction and characterization of partial digest DNA libraries made from flow-sorted human chromosome 16.

In this report, we present the techniques used for the construction of chromosome-specific partial digest libraries from flow-sorted chromosomes and the characterization of two such libraries from human chromosome 16. These libraries were constructed to provide materials for use in the development of a high-resolution physical map of human chromosome 16, and as part of a distributive effort on the National Laboratory Gene Library Project. Libraries with 20-fold coverage were made in Charon-40 (LA16NL03) and in sCos-1 (LA16NC02) after chromosome 16 was sorted from a mouse-human monochromosomal hybrid cell line containing a single homologue of human chromosome 16. Both libraries are approximately 90% enriched for human chromosome 16, have low nonrecombinant backgrounds, and are highly representative for human chromosome-16 sequences. The cosmid library in particular has provided a valuable resource for the isolation of coding sequences, and in the ongoing development of a physical map of human chromosome 16.

Animals↗