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J A Lanser

Publications and source records attributed to J A Lanser.

24 records · Page 2Linked to original sources
PubMed1985

DNA relatedness and biochemical features of Campylobacter spp. isolated in central and South Australia.

Investigations of the etiology of diarrhea in patients in South Australia and the Northern Territory showed that Campylobacter spp. other than Campylobacter jejuni and C. coli were common in children. Campylobacters which were hippurate positive, nitrate negative, and susceptible to cephalothin and polymyxins were shown to be closely related to C. jejuni by DNA studies. Thermotolerant catalase-negative campylobacters were also isolated. These were H2S negative and biochemically resembled the catalase-negative or weak strains found in dogs in Sweden. DNA studies showed these campylobacters to be distinct from C. sputorum subsp. sputorum and to form a homogeneous group distinct from the enteropathogenic catalase-positive campylobacters. Preliminary studies suggest that these campylobacters are related to the Swedish catalase-negative or weak strains.

Adult↗
PubMed1985

Detection of Escherichia coli adhesins with DNA probes.

DNA hybridization assays for genes encoding the Escherichia coli adhesins K88 and K99 were developed. These assays were used to screen a variety of animal E. coli strains, and the results were compared with results obtained by serological methods. All methods compared well for determining the presence of adhesin K99. However, the DNA hybridization detected more K88-positive strains than did either enzyme immunoassay or slide agglutination. Agreement was improved when strains were grown on blood or nutrient agar instead of Minca medium.

Adhesins, Escherichia coli↗
PubMed1980

The polypeptides of infectious bronchitis virus (IBV-41 strain).

The Massachusetts strain of avian infectious bronchitis virus was purified from embryonated hens' eggs. Four major species of apparent mol. wt. 90 000, 52 000, 29 000 and 26 000 were resolved by SDS-polyacrylamide gel electrophoresis. Omission of reducing agent failed to resolve the 29 000 mol. wt. component. Labelling of acrylamide gels with 125I-concanavalin A indicated that polypeptides of mol. wt. 90 000, 29 000 and 26 000 were glycosylated and, in the absence of reducing agent, that the 29 000 species migrated as a dimer in the 5000 mol. wt. region. Purified IBV radio-iodinated with Bolton and Hunter reagent, which banded as a single peak of radioactivity in Metrizamide gradients, was found to contain bands of radioactivity when analysed by SDS-PAGE, corresponding to the polypeptides of mol. wt. 90 000, 52 000 and 29 000 resolved in stained gels. Disruption of IBV particles in Triton X-100 released two subviral particles, a 16 nm spike which comprised polypeptides of 90 000, 52 000 and 29 000 mol. wt. and another denser spherical particle of 25 to 45 nm which contained RNA and the 52 000 and 26 000 polypeptides.

Bromelains↗
PubMedDate not supplied

Electrophoretic and immunoblot analysis of Cryptosporidium oocysts.

Cryptosporidium oocysts were recovered by density gradient centrifugation from diarrhoeal faeces of four human patients and one goat kid. Goat-derived oocysts were further treated with excystation medium and the excysted oocyst walls purified by isopycnic ultracentrifugation. Soluble extracts from intact oocysts and the oocyst wall preparation were analysed by SDS-PAGE. Fifty-one polypeptide bands were detected in intact oocyst preparations: 48 were in the range 14,000-200,000 molecular weight (MW), two bands were less than 14,000 MW and one band was above 200,000 MW. Twenty-one bands were detected in the oocyst wall preparation, all within the range 14,000-200,000 MW. Immunoblot analysis of Cryptosporidium polypeptides using acute or convalescent human and goat sera revealed a large number of reactive bands. Varying degrees of heterogeneity were observed within and between the two serum groups. Nine of the 10 human sera and all of the goat kid sera reacted with a 23,000 MW and 32,000 MW antigen. A 15,500 MW antigen was also detected by all the goat and four of the 10 human sera. Both serum groups reacted with various antigens above 40,000 MW. Surface labelling of three human isolates of Cryptosporidium oocysts with 125I was performed using the Bolton and Hunter reagent. The solubilized preparations were separated by SDS-PAGE on 12% and 18% slab gels and autoradiographed. Common bands were seen at 15,500, 32,000, 47,500, 79,000 and 96,000 MW. Some variation in the molecular weight of polypeptides labelled with 125I was observed among the three isolates.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗