Genomic DNA was extracted using the method of Marmur
(1961) from cells grown in RO medium for 2 days at
28
u
C, washed and resuspended in TE buffer
[
10 mM Tris-
HCl (pH 7.5), 1 mM EDTA (pH 8.0)
]
. Purity was assessed
using A
280
/A
260
and A
230
/A
260
ratios (Johnson, 1994).
Phylogenetic analyses based on 16S rRNA gene sequences
were performed as descri bed by Lin et al. (2007). The 16S
rRNA gen e was amplified with uni versal bacterial primers
corresponding to Escherichia coli positions 8F (5 9-AGA-
GTTTGATCCTGGCTCAG) and 1492R (59-GGTTACCT-
TGTTACGACTT) (Embley, 1991).