Abstract
Plant defensins are promising future strategy as antimicrobial agents; however the number of characterized plant defensins is very low. We isolated and studied the expression of plant defensins in six plants from Taif region. Using RT-PCR and two pairs of common as well as three pairs of specific primers, the defensin gene expression was analyzed. Plants showed differences in defensin gene expression in floral buds and leaves, though floral buds represented higher gene expression. The amino acid sequence of the six isolated cDNA sequences showed high similarity with other defensin accessions from the nucleotide database, especially in the cysteine rich motif. Phylogenetic analysis revealed that the isolated sequences share the common features of plant defensins, especially the 8 conserved cysteines. The results of this study help to detect some valuable Saudi plant sources for the development of natural peptides as a replacement for chemical antibiotics.