Cytochrome P450 monooxygenase; part of the gene cluster that mediates the biosynthesis of the phytotoxin tentoxin, an inhibitor the F1-ATPase activity of chloroplasts, resulting in chlorosis in sensitive plants (PubMed:27490569, PubMed:7881545). Tentoxin is a cyclic tetrapeptide that consists of four amino acid residues: glycine (Gly), alanine (Ala), leucine (Leu), and dehydrophenylalanine (DPhe) (PubMed:27490569, PubMed:7881545). In addition, both the Ala and DPhe residues are N-methylated (PubMed:27490569, PubMed:7881545). The nonribosomal peptide synthetase TES assembles tentoxin from the four substrate amino acids (PubMed:27490569). The adenylation domains of each of the 4 modules are responsible for the activation of Gly, Ala, Leu and DPhe, respectively (PubMed:27490569). In addition, the N-methyltransferase domains in the second and fourth modules of TES could be responsible for N-methylation of Ala and DPhe residues (PubMed:27490569). Finally, the condensation domain located in the termination module probably catalyzes the formation of the intramolecular macrocyclization and then the release of tentoxin (PubMed:27490569). The cytochrome P450 monooxygenase TES1 is predicted to be involved in the formation of DPhe (PubMed:27490569). Phytotoxin biosynthesis. Impairs the production of tentoxin (PubMed:27490569). Belongs to the cytochrome P450 family.