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H R Bose

Publications and source records attributed to H R Bose.

87 records · Page 5Linked to original sources

Homologous interference induced by Sindbis virus.

Homologous interference during Sindbis virus infection has been investigated. Prior infection of either chicken embryo fibroblast or BHK(21) cell cultures results in reduced yields of progeny virions of the superinfecting genotype. This reduction in yield results from a reduction in the number of cells in the cultures capable of producing the superinfecting genotype. The development of interference parallels the attachment kinetics of Sindbis virus. Interference requires an active viral genome since the activity is sensitive to inactivation by ultraviolet light, and an RNA(-) mutant, ts-24, fails to induce interference under nonpermissive conditions. However, ts-6, an RNA(-) mutant belonging to a different complementation group, and the RNA(+) mutants, ts-2 and ts-20, interfere at both permissive and nonpermissive temperatures.

Animals↗

Relationship of reticuloendotheliosis virus to the avian tumor viruses: nucleic acid and polypeptide composition.

The RNA content and polypeptide composition of reticuloendotheliosis virus (REV) was compared to that of C-type RNA tumor viruses. Two RNA species with approximate sedimentation values of 64S and 4S were observed after sucrose gradient centrifugation of RNA extracted from purified REV. The high-molecular-weight RNA species of REV sedimented slightly faster than that of the Bryan strain of Rous sarcoma virus (RSV). Although these characteristics were consistent with those of other C-type RNA tumor viruses, significant differences were observed when the polypeptide composition of REV was compared with that of RSV possessing envelope determinants of Rous-associated virus RAV-2 and RAV-3. Five polypeptides of which two were glycosylated were resolved by polyacrylamide gel electrophoresis. The major nonglycosylated polypeptide of REV did not comigrate with that of RSV (RAV-2)-RSV(RAV-3). The majority of the group-specific antigen reactivity resides in this major nonglycosylated polypeptide of avian tumor viruses and comigrates when proteins of several avian tumor viruses are subjected to coelectrophoresis. This difference in the migration of the major polypeptide of REV and RSV(RAV-2)-RSV(RAV-3) may explain the absence of avian tumor virus group-specific antigen in REV.

Alpharetrovirus↗

Correlation of messenger RNA function with adenylate-rich segments in the genomes of single-stranded RNA viruses.

Oligonucleotides enriched in adenylate residues have been demonstrated in the genomes of two positive-strand RNA viruses, Sindbis and Columbia SK. Such oligonucleotides were not found in the genome of vesicular stomatitis virus, a negative-strand virus. The adenylate-rich oligonucleotides from Sindbis and Columbia SK viruses appeared similar when analyzed by zonal sedimentation in sucrose-sodium dodecyl sulfate.

Adenine Nucleotides↗

Physiological studies of methane- and methanol-oxidizing bacteria: comparison of a primary alcohol dehydrogenase from Methylococcus capsulatus (Texas strain) and Pseudomonas species M27.

A primary alcohol dehydrogenase has been purified from Methylococcus capsulatus (Texas strain). The purified enzyme catalyzes the oxidation of methanol and formaldehyde to formate; other primary alcohols are oxidized to their corresponding aldehydes. Ammonium ions are required for enzyme activity. The enzyme has a molecular weight of 120,000 daltons and consists of two 62,000 molecular-weight subunits which dissociate at acidic pH. The enzyme is similar to an alcohol dehydrogenase enzyme isolated from Pseudomonas sp. M27.

Alcohol Oxidoreductases↗

Selective association of Sindbis virion proteins with different membrane fractions of infected cells.

Plasma and smooth membranes obtained from chicken embryo cells infected with Sindbis virus were solubilized and subjected to electrophoresis on acrylamide gels. The electrophoretic patterns showed that (i) the major proteins synthesized and associated with plasma membranes from infected cells are virion proteins and (ii) at 4 hr after infection virion proteins are not present at detectable levels in the smooth membranes of the cell.

Amino Acids↗

Separation of reticuloendotheliosis virus from avian tumor viruses.

Velocity sedimentation and isopycnic density gradient centrifugation indicate that reticuloendotheliosis virus has a different mass and buoyant density than members of the avian tumor virus group. The group-specific antigen of the avian tumor virus group was not detected in concentrated and purified reticuloendotheliosis virus preparations.

Alpharetrovirus↗

Replication of the reticuloendotheliosis virus (strain T) in chicken embryo cell culture.

Investigations were conducted on the in vitro replication of the reticuloendotheliosis (RE) virus (strain T) in specific-pathogen-free chicken embryo fibroblast (CEF) cultures. Active virus production was detected in the tissue culture fluid 24 hr after infection. When injected into chickens, samples taken 42 hr after infection of the cell cultures killed approximately 50% of the birds at a 1:100 dilution. The RE virus titer remained at this level for 5 days before declining. Cell-free virus preparations from tissue cultures rarely resulted in 100% mortality of the assay birds. The level of cell-associated virus was very low. Evidence that the reticuloendotheliosis was not induced by a mycoplasma was indicated by failure to isolate an organism on PPLO Agar (Difco) and failure of kanamycin or amphotericin B to inhibit multiplication of RE virus in vitro. RE virus appeared to be unrelated to members of the avian leukosis and sarcoma complex. It did not induce resistance in CEF cultures to sarcoma viruses of the A or B subgroup of this complex. Similarly, preinfection of cell cultures with leukosis viruses of the A or B subgroup did not inhibit or reduce the replication of RE virus.

Alpharetrovirus↗