Simple transport medium for Bacteroides ureolyticus

Restriction endonuclease analysis and ribotyping differentiate genital and nongenital strains of Bacteroides ureolyticus

Thirty-three clinical isolates from male nongonococcal urethritis and 28 isolates from soft tissue infections and ulcers were identified as Bacteroides ureolyticus by conventional bacteriological tests and were compared with five reference strains of the species. Whole-cell proteins from these clinical isolates and the reference strains were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The majority of the strains from the two sources could be divided into five different groups, named phenons I to V; phenons I to IV have been described previously by others, while phenon V has been described recently by us. Digestion of chromosomal DNA from 16 of the clinical isolates (including strains representative of each of the five SDS-PAGE phenons) and the five reference strains was attempted with restriction endonucleases EcoRI, PstI, SmaI, and HindIII. After electrophoresis in agarose gels, good digestion was observed with HindIII only, and 12 different banding patterns (restriction endonuclease analysis [REA] profiles) were obtained for the 19 strains digested; one nongonococcal urethritis isolate and one reference strain did not show any digestion. From the agarose gels, HindIII-digested fragments of DNA were transferred to nylon membranes by use of vacuum blotting and subjected to hybridization with 32P-labelled 16S-23S rRNA from Escherichia coli. The resultant pattern of bands (ribotypes), which depends on the restriction fragment length polymorphisms in the rRNA genes, was used as a measure of genomic variation within the species. In total, 13 different ribotypes were obtained for the 19 strains. For some strains, good correlation was achieved among the SDS-PAGE phenons, REA profiles, and ribotypes. However, for others, REA analysis and ribotyping were able to discriminate between strains which shared the same SDS-PAGE phenon. Interestingly, these two techniques of DNA characterization were able to differentiate between isolates from the genital tract and those associated with soft tissue infections and ulcers.

Isolation of Bacteroides ureolyticus from the genital tract of men with and without non-gonococcal urethritis

Urethral specimens from 247 heterosexual men--118 patients with non-gonococcal urethritis and 129 controls with no evidence of urethritis--were examined for the presence of Bacteroides ureolyticus. Bacteroides ureolyticus was isolated from 45 (34.9%) of the controls and from 31 (26.3%) of the urethritis patients; there was no significant difference between these rates (p = 0.1). There was no association between the density of Bacteroides ureolyticus on primary isolation plates in either group.