The structure of Phalaenopsis PR1. (A) A schematic diagram of PhaPR1. The full-length, 169 amino acid protein contains a predicted signal peptide (SP) of 21 residues in length indicated in gray, the 4 α-helixes are indicated (), and the 4 β-sheets are also shown (). The 6 conserved cysteine residues are also indicated with C1-C6. (B) Alignment of PhaPR1 (underlined) with PR-1-like proteins, which have antimicrobial functions, and STS14-like proteins. The mature protein sequences were used for the analysis. Their accession numbers are OsPR1a (NP_001058815), AtPR1 (AT2G14610), LeP14a (NP_001234314), NtPR1a (CAA31233), NtPR1b (CAA47374), NtPR1c (CAA35666), AtSTS14 (AT5G66590), VvSTS14 (XP_003635089), and MtSTS14 (XP_003611867).