Characterization by restriction endonuclease analysis and DNA hybridization using IS900 of bovine, ovine, caprine and human dependent strains of Mycobacterium paratuberculosis isolated in various localities.

DNA of 90 mycobactin-dependent strains of Mycobacterium paratuberculosis, isolated in 9 countries, was digested with restriction endonuclease PstI and hybridized with a DNA fragment containing insertion sequence IS900. Bovine strains (n = 73) were isolated from 61 animals in 17 herds, ovine strains (n = 15) from 13 animals in 3 herds and the set was completed by 1 caprine and 1 human (Linda) strain. Three types, tentatively designated A (n = 37), B (n = 51) and C (n = 2) were differentiated by restriction fragment length polymorphism (RFLP). Of the bovine strains 27, 45 and 1 were classified as belonging to types A, B and C, respectively; of the 15 ovine strains 10 and 5 belonged to types A and B, respectively; the caprine strain belonged to type C. The human strain Linda, isolated in the U.S.A., from a man with Crohn's disease, belonged to B type. A certain degree of type uniformity was observed among strains isolated within one herd in the course of several years, and the prevalence of a single type was also recorded within individual regions of the Czech Republic and Slovakia. Type A was identified in the course of 2 years in a sheep farm with frequent sales and purchases of animals, and type C was demonstrated in a goat kept in the same farm. Differences between RFLP types of the strains isolated from mesenteric lymph nodes and intestinal mucosa were found in one cow and one sheep. Selected strains of M. paratuberculosis RFLP type A (14 strains) and B (18 strains) were digested with restriction endonuclease BstEII. All the strains of A type were classified into C1 group and all the strains of B type into Cx group.

Oligonucleotide (GTG)5 in bacterial DNA fingerprinting.

On a set of 198 bacterial strains out of 19 different species we have tested the ability of oligonucleotide (GTG)5 to provide definitive DNA fingerprints. All the tested bacteria gave rise to at least one band after digestion with Hinf I and hybridization with radioabelled oligonucleotide (GTG)5. The number of resulting bands varied considerably from species to species and correlated strongly with the GC content of individual bacterial species. A set of 13 well defined laboratory strains of Escherichia coli was divided into 3 groups after GTG fingerprinting, while standard ribotyping revealed no differences. GTG fingerprinting is simple and reliable method for typing bacteria and may be of particular value in those bacterial species, where no other typing systems are available.

[Occurrence, economic significance and diagnosis of paratuberculosis]. / Výskyt, ekonomický význam a diagnostika paratuberkulózy.

Paratuberculosis is the most serious chronic bacterial disease of ruminants. Regarding the increasing incidence of the disease in the Czech Republic in connection with changing situation in agriculture and, among other factors, with import of animals we are presenting a summary of the latest data. We assume that high economic losses and expected participation of Mycobacterium paratuberculosis in Crohn's disease in men will evoke a broad interest in the disease among people from various branches of veterinary and human diagnosis.