7. Genotypic identification of fungi isolates
Nucleotide sequencing of rRNA genes of some Penicillium species
was done with the help of SolGent Company, Daejeon,
South Korea. Primers used for gene amplification have the following
composition: ITS1 (50-TCC GTA GGT GAA CCT
GCG G-30), and ITS4 (50-TCC TCC GCT TAT TGA TAT
GC-30). Then the amplification was carried out in a thermal
cycler under the following conditions: one round of denaturation
at 95 C for 15 s followed by 30 cycles of denaturation
at 95 C for 20 s, annealing at 50 C for 40 s and extension
at 72 C for 1 min, with a final extension step at 72 C for
5 min. The PCR products were then purified with the SolGent
PCR Purification Kit-Ultra (SolGent, Daejeon, South Korea)
prior to sequencing. Purified PCR products were reconfirmed
(using size marker) by electrophoreses on 1% agarose gel.
Then these bands were eluted and sequenced with the incorporation
of dideoxynucleotides (dd NTPs) in the reaction mixture.
Each sample was sequenced in the sense and antisense
directions using ITS1 and ITS4 primers (White et al., 1990).
Sequences were further analyzed using BLAST from the
National Center of Biotechnology Information (NCBI)
website. Phylogenetic analysis of sequences was done with
the help of MegAlign (DNA Star) software version 5.05.