Restriction endonuclease digest patterns of chromosomal DNA from nitrate-negative Campylobacter jejuni-like organisms

Abstract

High molecular weight chromosomal DNA was isolated from ten nitrate-negative campylobacters of human origin (gastric biopsies and faecal specimens). The DNA was digested with various restriction endonucleases and the patterns obtained were compared with those of Campylobacter coli, C. fetus subsp. fetus, C. jejuni and C. laridis reference strains. Electrophoresis of Hae III digests of DNA in 0.5% agarose gave excellent patterns which comprised at least 25 well-resolved bands with fragment sizes between about 4 and 40Kb. There were distinct differences between strains from different geographical locations. The six gastric strains from West Germany formed a relatively homogeneous group with respect to their band patterns (type I and II), whereas the U.K. gastric isolate had a slightly different pattern (type III) as did the three Australian faecal isolates (types IV, V and VI). No plasmids were detected in these nitrate-negative campylobacters and differences in DNA digest patterns between strains and representatives of allied species were attributed to variations in the distributions of Hae III recognition sequences within the genome. The patterns provided further evidence that the strains were atypical C. jejuni.

DNA restriction digest and ribosomal RNA gene patterns ofCampylobacter jejuni: a comparison with bio-, sero-, and bacteriophage-types of United Kingdom outbreak strains

“…Both of these outbreak strain sets were different, however, by Lior serotyping, phage typing and DNA grouping. This finding highlights the excellent discriminatory power of the DNA grouping technique and confirms the value of using at least two different typing techniques when testing strains from different outbreaks [11][12][13][14][15]. Our results show clearly that both biotyping and DNA grouping have a major advantage over serotyping and phage typing in that strains of C. jejuni, which are untypable by the latter two methods, always give a result with biotyping and DNA grouping.…”

“…Comparisons of DNA digest patterns have been used in conjunction with serotyping in several epidemiological studies of C. jejuni [15,16] and in the characterization of cross-reacting serotypes of C. jejuni [27]. In the present study we have examined ribopatterns as well as total digest patterns because the former are comprised of less complex patterns of bands and facilitate between-strain comparisons.…”

“…At present the most promising and widely used methods are biotyping according to the schemes of Lior [7] and Bolton [8], and serotyping using heat-stable (HS) [9] and heat-labile (HL) [10] surface antigens. Other schemes for typing C. jejuni have included fluorescent antibody tests [11], 266 R. J. OWEN, J. HERNANDEZ AND F. BOLTON auxotyping [12], phage typing [13], and DNA restriction endonuclease analysis [14][15][16]. For epidemiological purposes, some investigators have proposed that improved discrimination can be achieved by the combination of several typing systems [17,18].…”

NOTES: Campylobacter jejuni subsp. doylei subsp. nov., a Subspecies of Nitrate-Negative Campylobacters Isolated from Human Clinical Specimens

“…Subsequent DNA dot blot hybridization studies have shown that the Australian strains are also closely related to the South African isolates (Steele, unpublished data). HaeIII restriction endonuclease digestion analysis of chromosomal DNA revealed distinct differences between strains from different geographical locations (10). The six West German gastric isolates all had almost identical band patterns, whereas the band patterns of the British (gastric) and Australian (fecal) isolates were different.…”

“…All isolates were obtained from children that were less than 5 years old and were admitted to hospital with diarrhoea in Central Australia. Similar strains have now been isolated from a small number of aboriginal children in South and Western Australia, from children with diarrhoea in South Africa (9), and from gastric biopsies of adults in West Germany (7) and the United Kingdom (10).…”