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Geology topics

W. B. Schill

Publications and source records attributed to W. B. Schill.

34 records · Page 2Linked to original sources
USGS1986

Immunoblot assay: a rapid and sensitive method for identification of salmonid fish viruses

An immunoblot assay was used to identify the viruses of infectious pancreatic necrosis, infectious hematopoietic necrosis, and viral hemorrhagic septicemia. Viral antigen in infected cell culture supernatant was adsorbed onto nitrocellulose membrane or Whatman 541 filter paper and detected by enzyme-linked immunosorbent assay techniques. The immunoblot assay took less than 4 hr to perform and required no special instrumentation. Assays using cell culture supernatant fluids showed immunoblot sensitivity was 10 5 –10 6 PFU/ml. Assay sensitivity, determined using purified virus, is 0.85–4.0 ng of viral antigen. The immunoblot assay was used to detect and identify virus in cell culture fluids.

Journal of Wildlife Diseases↗
USGS1986

An epizootic in chinook salmon (Oncorhynchus tshawytscha) caused by a sorbitol-positive serovar 2 strain of Yersinia ruckeri

Enteric redmouth disease is described in chinook salmon ( Oncorhynchus tshawytscha ) at a state hatchery in Sand Ridge, Illinois. Biochemical, isoenzyme, and serological data indicated that the epizootic was caused by a sorbitol-fermenting Serovar 2 strain of Yersinia ruckeri . In laboratory experiments the isolate was pathogenic for both brook trout ( Salvelinus fontinalis ) and Atlantic salmon ( Salmo salar ).

Journal of Wildlife Diseases↗
USGS1985

Rapid serological analysis of bacterial lipopolysaccharides by electrotransfer to nitrocellulose

Techniques are described for the rapid screening of proteinase K-treated bacterial lysates by electroblot and immunoenzymatic detection to assess O-specificity of antigens and antisera. Conditions are outlined which permit the use of a single polyacrylamide gel for both electrotransfer to nitrocellulose and silver staining. Immunodetection of transferred LPS bands was equally sensitive to silver stain when whole cell or O-specific antisera were used. The techniques were utilized to identify at least 4 O-serotypes among sorbitol fermenting isolates of the fish pathogen, Yersinia ruckeri . Observed variations in the electrophoretic mobilities of lipopolysaccharides from 17 field isolates of Y. ruckeri were used to accurately predict the O-serotype.

Journal of Immunological Methods↗
USGS1984

Fish cell lines: Characterization by isozyme analysis

The electrophoretic mobilities of isozymes from 16 enzyme systems were determined for nine fish cell lines. The relative migration of the malate dehydrogenase and 6-phosphoglucose dehydrogenase isozymes could be used together to distinguish between seven of the fish cell lines. Two cyprinid cell lines could not be distinguished from each other but were readily separated from the six noncyprinid lines and the one other line of cyprinid origin.

In Vitro↗
USGS1984

Multilocus electrophoretic assessment of the genetic structure and diversity of Yersinia ruckeri

Multilocus isoenzyme electrophoresis was used to screen 47 field isolates of Yersinia ruckeri for electrophoretic variation at 15 enzyme loci. Only four electrophoretic types were observed, thus indicating that the genetic structure of Y. ruckeri is clonal. Forty-two isolates were of one electrophoretic type, a reflection of the low amount of genetic diversity extant in this species. Although sorbitol fermentation has been considered to be indicative of a second biotype, no significant gene frequency differences were found between the group of 20 isolates that readily used sorbitol as the sole carbon source and the group of 27 that did not.

Applied and Environmental Microbiology↗