Antimicrobial peptides (AMPs) play an essential role in plant defense against invading pathogens. Due to their biological properties, these molecules have been considered useful for drug development, as novel agents in disease therapeutics, applicable to both agriculture and medicine. New technologies of massive sequencing open opportunities to discover novel AMP encoding genes in wild plant species. This work aimed to identify cysteine-rich AMPs from Peltophorum dubium, a legume tree from South America. We performed whole-transcriptome sequencing of P. dubium seedlings followed by de novo transcriptome assembly, uncovering 78 AMP transcripts classified into five families: hevein-like, lipid-transfer proteins (LTPs), alpha hairpinins, defensins, and snakin/GASA (Giberellic Acid Stimulated in Arabidopsis) peptides. No transcripts with similarity to cyclotide or thionin genes were identified. Genomic DNA analysis by PCR confirmed the presence of 18 genes encoding six putative defensins and 12 snakin/GASA peptides and allowed the characterization of their exon-intron structure. The present work demonstrates that AMP prediction from a wild species is possible using RNA sequencing and de novo transcriptome assembly, regarding a starting point for studies focused on AMP gene evolution and expression. Moreover, this study allowed the detection of strong AMP candidates for drug development and novel biotechnological products.

抗菌肽（AMP）在植物防御入侵病原体中起着至关重要的作用。由于它们的生物学特性，这些分子已被认为可用于药物开发，作为疾病治疗学中的新型药物，适用于农业和医学。大规模测序的新技术为在野生植物物种中发现新的AMP编码基因提供了机会。这项工作旨在从南美豆科植物Peltophorum dubium鉴定富含半胱氨酸的AMP 。我们对P. dubium幼苗进行了全转录组测序，然后进行了从头测序转录组组装，发现78个AMP转录本，分为五个家族：类肝素，脂质转移蛋白（LTP），α发夹蛋白，防御素和snakin / GASA（拟南芥刺激的吉贝酸）肽。没有发现与环氧化物或硫蛋白基因相似的转录物。通过PCR进行的基因组DNA分析证实，存在18个编码6个假定防御素和12个snakin / GASA肽的基因，并可以表征其外显子-内含子结构。目前的工作表明，使用RNA测序和从头进行野生物种的AMP预测是可能的转录组组装，这是研究集中在AMP基因进化和表达的起点。此外，这项研究还可以检测出用于药物开发和新型生物技术产品的强AMP候选药物。