2.4. DNA extraction and molecular phylogenetic analyses using
16S rRNA gene sequence
Genomic DNA was isolated from C1 strain following the
method of Johnson (1994). The 16S rDNA genes was amplified
with broadly conserved bacterial 16s rDNA primers SSU16s-F
(50-AAC TCC TAC GGG AGG CAG CAG-30) and SSU16s-R
(50-AAG GAC TAC CAG GGT ATC TAA TCC-30) which
yielded PCR products of about 0.4 Kb (Wilmotte et al., 1993).
The nucleotide sequences of the amplified small subunit rRNA
genes were determined bidirectionally with same SSU 16s primers
according to Shaikh and Tarr (2003).Acontinuous stretch of
415-nucleotide 16S rRNA gene sequences was used to search for
similar sequences from RDP database site. After confirmation
of generic affiliation, sequences from type strains of different
species were retrieved from NCBI GenBank. A phylogenetic
tree was constructed showing relationship between C1 strain
and other reference strains by neighbor joining (NJ) method
with Jukes and Cantor correction using TREECON software
as described by Saha and Chakrabarti (2006).