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H D Mayor

Publications and source records attributed to H D Mayor.

At least 55 records · Page 3Linked to original sources

Plus and minus single-stranded DNA separately encapsidated in adeno-associated satellite virions.

Based on physical and chemical determinations, the mnolecular weight of the type 4 adeno-satellite virus is 5.4 X 10(6) daltons, and the virion contains 1.4 X 10(6) daltons of DNA. Denaturation and renaturation studies indicate that the viral genome is a single-stranded DNA molecule and that each virion contains either a minus or a plus strand. Upon extraction, the minus and plus strands unite to form double-stranded DNA molecules with no obvious excess of unpaired strands.

Adenoviridae↗

Interference between two adeno-associated satellite viruses: a three-component system.

Adenovirus-associated satellite viruses interfere with the replication of their helper adenoviruses. According to a previous report, this interference is not mediated by interferon. A three-component system comprising simian adenovirus SV15 and satellites types 1 and 4 was studied to determine whether satellite viruses also interfere with one another. Satellite type 1 interfered with the replication of type 4 and vice versa. The degree of interference was directly proportional to the dose of interfering satellite. The events leading to mutual satellite interference were operative during the first 12 hr of replication, the period associated with active synthesis of viral deoxyribonucleic acid.

Adenoviridae↗

Nucleic acid molecules: new microdiffusion technique for visualization.

A microdiffusion technique, developed for visualization of nucleic acid molecules in the electron microscope, requires less than 0.01 microgram of nucleic acid. Although originally developed for free nucleic acids, the method can be applied to virion suspensions for direct visualization of their genomes; less than 10(10) virions per milliliter are required. Results agree well with those yielded by the diffusion technique of Lang, Kleinschmidt, and Zahn.

Adsorption↗

Physical assay and growth cycle studies of a defective adeno-satellite virus.

Electron microscopic particle counting of the defective adeno-satellite virus (ASV), by use of pseudoreplication and negative staining with phosphotungstic acid, was shown to be a reproducible quantitative assay procedure. Particles of satellite type 4 that were counted in fluids from infected cultures had the same morphology as particles that banded at a buoyant density of 1.43 g/cc in cesium chloride. Other satellite virus serotypes examined in the same manner had a buoyant density of 1.37 to 1.38 g/cc. A comparison of satellite titers obtained by complement fixation and by particle counting demonstrated that an increase in satellite particles resulted in a corresponding increase in CF titers; however, electron microscopy was at least 10 times more sensitive than complement fixation for detecting satellite virus. Growth cycle studies of satellite virus in cells co-infected with adenovirus, as assayed by particle counting, indicated that the kinetics of satellite virus production closely followed the kinetics of its helper adenovirus production, with an eclipse period of 12 to 16 hr. The eclipse period of the satellite remained the same when cultures were preinfected with satellite 24 hr prior to adenovirus inoculation. However, when cultures were infected with adenovirus 12 hr before satellite virus, the eclipse period of the satellite was shortened to between 4 and 6 hr. Thus, satellite virus replication seems dependent upon a relatively late event in the adenovirus replication cycle. When cells were co-infected with adenovirus and its defective satellite, the yield of adenovirus was markedly reduced from that obtained in cells singly infected with adenovirus.

Adenoviridae↗

Comparative study of seven picornaviruses of man.

Jamison, Richard M. (Baylor University College of Medicine, Houston, Tex.), and Heather D. Mayor. Comparative study of seven picornaviruses of man. J. Bacteriol. 91:1971-1976. 1966.-The buoyant densities in CsCl and potassium tartrate of seven acid-resistant picornaviruses of man were determined. The viruses studied were found to be a relatively homogeneous group. Buoyant densities ranged from 1.32 to 1.35 g/cc in CsCl and 1.21 to 1.23 g/cc in potassium tartrate. The buoyant density of each virus did not vary by more than 0.01 g/cc. The host cell of origin and passage level did not influence the buoyant density of the virions. However, measurements of the diameters of purified virions by a standard method have shown that there are considerable size variations among these picornaviruses. The diameters ranged from 18 to 25 mmu. Echovirus 19 and poliovirus 1 were significantly larger (mean diameter, 23.5 mmu) than echoviruses 4, 6, 16, and 23, and coxsackievirus B2 (mean diameter, 21.0 mmu).

Enterovirus↗

Structure and Composition of a Small Particle Prepared from a Simian Adenovirus.

Mayor, Heather D. (Baylor University College of Medicine, Houston, Tex.), Richard M. Jamison, Liane E. Jordan, and Joseph L. Melnick. Structure and composition of a small particle prepared from a simian adenovirus. J. Bacteriol. 90:235-242. 1965.-When tissue-culture fluids infected with simian adenovirus SV15 are examined in an electron microscope, either as fresh harvests or after treatment with Genetron, typical mature adenovirus particles are found. These are 65 to 70 mmu in diameter, with an icosahedral capsid built from 252 capsomeres. Also present is a population of small polyhedral particles approximately 20 mmu in diameter. These small particles can be separated from the mature virions by ultrafiltration or density gradient centrifugation. The small particles have a density of 1.43 in cesium chloride. They contain protein and double-stranded deoxyribonucleic acid. They appear to possess cubic symmetry of the icosahedral type, with a coat composed of 12 subunits each at the vertex of an icosahedron.

Journal Article↗