Thirteen reference strains, including the type strains of the type species of the genus
Gluconobacter,
Gluconobacter oxydans (NBRC 14819
T),
Gluconobacter cerinus (NBRC 3267
T), and
Gluconobacter frateurii (IFO 3264
T) were examined for their species identification based on the sequence and the restriction analyses of the 16S–23S rDNA internal transcribed spacer (ITS) regions. A phylogenetic tree constructed by the neighbor-joining method represented three clusters corresponding respectively to the three species,
G. oxydans,
G. cerinus, and
G. frateurii. The type strain of
Gluconobacter asaii (NBRC 3276
T), which is a junior subjective synonym of
G. cerinus, was included completely in the
G. cerinus cluster. Several restriction endonucleases discriminating the three species from one another were selected by computer analyses:
Bsp1286I,
MboII,
SapI,
Bpu10I,
EarI,
BsiHKAI, and
FatI. On digestion of the PCR products with restriction endonucleases
Bsp1286I and
MboII, all the restriction patterns coincided with those of the type strains of the three species except for strain NBRC 3251. This strain gave a different pattern from the type strain of
G. frateurii, when digested with
MboII. However, strain 3251 was included phylogenetically in the
G. frateurii cluster. All the reference strains were thus identified at the species level by the sequence and the restriction analyses of the 16S–23S rDNA ITS regions.
View full abstract