The 16S rRNA gene sequences of the three isolates were
determined according to a previously described method
(Endo & Okada, 2005). The closest recognized relatives of
the isolates were determined by performing database
searches and sequences of closely related species were
retrieved from the DDBJ. Multiple alignments of the
sequences were carried out with the CLUSTAL_X program
version 1.18 (Thompson et al., 1997). Distance matrices for
the aligned sequences were calculated by using the twoparameter
method of Kimura (1980). The neighbourjoining
method was used to construct a phylogenetic tree
(Saitou & Nei, 1987). The robustness of individual
branches was estimated by bootstrapping with 1000
replicates (Felsenstein, 1985).