Isolation and characterization of ruminal spirochetes

Abstract

Three strains of rumen spirochetes have been isolated from the rumen fluid sample. Phase-contrast and epifluorescence microscopy have been used for morphological observation of isolated strains. For further characterisation rapid biochemical tests (API 50CH) and molecular biological analysis have been used. The morphological observations showed that two of the isolated strains SM1 and SM3 are similar and differ significantly from the strain SM2. All three isolated strains of rumen spirochetes are Gram-negative. The SM1 and SM3 cells were smaller than SM2 cells. Smaller were also the amplitude and the wavelength of coils of SM1 and SM3 cells. SM1 and SM3 strains utilised seven of 49 tested charbohydrates, whereas strain SM2 utilised additional 14 sugars. The literature data describing sugar fermentation in T. bryantii and T. saccharophilum showed significant differences between type strains T. bryantii and T. saccharophilum and strains SM1 and SM3. The strain SM2 seems to be similar to the type strain of T. saccharophilum. Large differences between analysed strains were found with theoretical and experimental RFLP analysis using different restriction enzymes of the 16S rRNA gene.