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Biomedical subjects

P Faulkner

Publications and source records attributed to P Faulkner.

At least 55 records · Page 3Linked to original sources
PubMed1972

Genome of Sindbis virus.

(32)P-labeled ribonucleic acid (RNA) from purified Sindbis virus was examined for the presence of hidden breaks. Viral RNA was treated with acid at pH 2.9 or with formaldehyde and was analyzed on sucrose gradients or by polyacrylamide gel electrophoresis. The sedimentation pattern and mobility on polyacrylamide gels of the 42S RNA was unaffected by heating and quick cooling and was not altered by denaturing agents such as dimethyl sulfoxide and urea. No evidence that Sindbis RNA is a polyaggregate of fragments was obtained. It is concluded that the genome consists of a continuous length of single-stranded polynucleotide.

Animals↗
PubMed1969

Properties of 42S and 26S Sindbis viral ribonucleic acid species.

Two species of ribonuclease-sensitive Sindbis viral ribonucleic acids which sedimented at 42S and 26S were studied. 42S RNA, derived either from virions or from viral nucleoids extracted from infected cultures, was converted by heating to an RNA which sedimented at 26S. The sedimentation patterns of 42S RNA and "derived" 26S RNA were similarly affected in low ionic strength buffers. 42S RNA ran as a homogeneous fraction on polyacrylamide gels; the "derived" 26S RNA as well as "natural" 26S RNA from infected cultures showed similar electrophoretic patterns of heterogeneity. A doubling of 3' polynucleotide termini was observed when 42S RNA was heated. Two possibilities concerning the structure of 42S RNA are considered. (i) It may consist of an aggregate of subunits, joined by means of hydrogen bonds to form a complex molecule. (ii) A heat-labile covalent bond of unknown type may link viral RNA subunits. Although 26S RNA from infected cultures and "derived" 26S RNA from 42S RNA behaved in a similar qualitative manner on gels, their sedimentation characteristics were affected differently in low ionic strength buffers. "Natural" and "derived" 26S RNA appear to consist of a population of fragments. and their behavior in gradients and in gels is probably dictated by the experimental conditions of the analytical methods used.

Animals↗
PubMedDate not supplied

Recombinant beta-galactosidase production in serum-free medium by insect cells in a 14-L airlift bioreactor.

Spodoptera frugiperda (Sf9) insect cells were successfully cultured in serum-free medium in a 14-L airlift bioreactor. Cell densities as high as 1 x 10(7) cells/mL were achieved with specific growth rates of approximately 0.0286 h-1 (doubling time of 24 h). This system was also used to demonstrate the expression of a reported gene, beta-galactosidase (beta-gal), when cells were infected with a recombinant baculovirus. Approximately 0.33 mg of beta-gal/mL (i.e., 104,000 units/mL) of medium were obtained at the 14-L scale, while about 0.95 mg of beta-gal/mL (i.e., 285,000 units/mL) of medium were obtained in small-scale shaker flasks. The difference was attributed to a suboptimal infection in the large scale. Specific oxygen consumption rates decreased from 5.58 x 10(-17) mol O2/cell.s in early exponential growth to 3.13 x 10(-17) mol O2/cell.s at 3 days post-infection.

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