Pathogenesis-related protein 1 (PR-1) is a critical component of plant defense mechanisms, exhibiting significant antifungal activity. This study focused on the PR-1 protein from Zea mays and five other plant species wheat, barley, rice, oats, and rye to explore their physicochemical, structural, and functional characteristics. The PR-1 gene was successfully isolated from Z. mays and amplified using Polymerase Chain Reaction (PCR). Following cloning into the pET15b vector, the gene was expressed in BL21-DE3 (E. coli) cells. Induction with 1mM Isopropyl β-D-1-thiogalactopyranoside (IPTG) for 4 hours at 37°C led to successful protein expression, as confirmed by 12% SDS-PAGE. The PR-1 protein exhibited resistance against a broad spectrum of oomycete pathogens, demonstrating its potential for developing fungi-resistant transgenic plants. The study revealed that PR-1 proteins from different plant species shared high sequence similarity, with identities ranging from 65–90%. However, their physicochemical properties varied based on plant origin. PR-1 proteins from cereals (maize, wheat, barley, and rice) were found to be more hydrophobic compared to those from grasses (oats and rye). Structurally, all PR-1 proteins adopted a similar three-dimensional conformation, featuring a central beta-barrel surrounded by alpha-helices. Functional assays confirmed that all six PR-1 proteins exhibited antifungal activity against a diverse array of fungal pathogens. The PR-1 protein from Z. mays, along with PR-1 proteins from other plant species, shows significant potential for agricultural biotechnology. By incorporating these genes into crop plants, it is possible to enhance their resistance to fungal pathogens, thereby advancing the development of more resilient and sustainable agricultural systems.