Amplification of the V. harveyi hemolysin gene (vhh)
PCR primers reported by Zhang and co-workers
(2001) were used to amplify the 1.3 kb open reading
frame of the hemolysin gene in the reference strain V.
harveyi IFO 15634 (Fig. 1). The identity of the PCRamplified
1.3 kb product was verified by direct sequencing
and BLAST homology search. The partial
nucleotide sequence displays 95% homology with the
reported Vibrio harveyi vhhA and vhhB genes deposited
in the GenBank database (data not shown).
Subsequently, other nested primers were designed in
this study in order to amplify internal hemolysin vhh
gene fragments in the V. harveyi reference strain.
Primer sequences used (Table 3) include a primer set
F2 and R2 designed in this study, generating a 216-bp
hemolysin gene fragment. PCR reactions using combinations
of the old and new primers and template DNA
from the reference V. harveyi strain, was observed to
yield amplified fragments with the following approximate
sizes: 308 bp and 1.2 kb (with primer sets, F1R2