title: Isolation and Some Properties of the Antimicrobial Peptide (Pa-AMP) from the Seeds of Pokeweed (Phytolacca americana).
abstract: An antimicrobial peptide, designated Pa-AMP, was purified by gel filtration on Sephadex G-75 followed by S-Sepharose, Cosmosil-SP, and reverse-phase HPLC from the seeds of pokeweed (Phytolacca americana). Pa-AMP is a basic peptide having an isoelectric point of over 10 and its extinction coefficient at 280 nm of 1% aqueous solution was 7.7. Pa-AMP has a molecular mass of 4 kDa and 3.4 kDa on tricine SDS-PAGE under nonreducing and reducing conditions, respectively. The N-terminal amino acid of Pa-AMP was blocked. The concentrations of peptide required for 50% inhibition (IC50) of the growth of plant pathogenic fungi, Gram-positive, and Gram-negative bacteria were 3 to 41 μg/ml. Differing from other peptides, Pa-AMP inhibited the growth of some Gram-negative bacteria.
authors.affiliation: a Department of Biochemical Science and Technology, Faculty of Agriculture, Kagoshima University.
authors.forename: Y
authors.initials: Y
authors.lastname: Minami
authors.affiliation: a Department of Biochemical Science and Technology, Faculty of Agriculture, Kagoshima University.
authors.forename: S
authors.initials: S
authors.lastname: Higuchi
authors.affiliation: a Department of Biochemical Science and Technology, Faculty of Agriculture, Kagoshima University.
authors.forename: F
authors.initials: F
authors.lastname: Yagi
authors.affiliation: a Department of Biochemical Science and Technology, Faculty of Agriculture, Kagoshima University.
authors.forename: K
authors.initials: K
authors.lastname: Tadera
keywords: Pa-AMP; Phytolacca americana; antimicrobial peptide; plant defense-related peptide; pokeweed