title: Development of a Novel Tetravalent Synthetic Peptide That Binds to Phosphatidic Acid.
abstract: We employed a multivalent peptide-library screening technique to identify a peptide motif that binds to phosphatidic acid (PA), but not to other phospholipids such as phosphatidylcholine (PC), phosphatidylethanolamine (PE), and phosphatidylserine (PS). A tetravalent peptide with the sequence motif of MARWHRHHH, designated as PAB-TP (phosphatidic acid-binding tetravalent peptide), was shown to bind as low as 1 mol% of PA in the bilayer membrane composed of PC and cholesterol. Kinetic analysis of the interaction between PAB-TP and the membranes containing 10 mol% of PA showed that PAB-TP associated with PA with a low dissociation constant of KD = 38 ± 5 nM. Coexistence of cholesterol or PE with PA in the membrane enhanced the PAB-TP binding to PA by increasing the ionization of the phosphomonoester head group as well as by changing the microenvironment of PA molecules in the membrane. Amino acid replacement analysis demonstrated that the tryptophan residue at position 4 of PAB-TP was involved in the interaction with PA. Furthermore, a series of amino acid substitutions at positions 5 to 9 of PAB-TP revealed the involvement of consecutive histidine and arginine residues in recognition of the phosphomonoester head group of PA. Our results demonstrate that the recognition of PA by PAB-TP is achieved by a combination of hydrophobic, electrostatic and hydrogen-bond interactions, and that the tetravalent structure of PAB-TP contributes to the high affinity binding to PA in the membrane. The novel PA-binding tetravalent peptide PAB-TP will provide insight into the molecular mechanism underlying the recognition of PA by PA-binding proteins that are involved in various cellular events.
authors.affiliation: Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Kyoto, Japan.
authors.forename: Rina
authors.initials: R
authors.lastname: Ogawa
authors.affiliation: Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Kyoto, Japan.
authors.forename: Kohjiro
authors.initials: K
authors.lastname: Nagao
authors.affiliation: Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Kyoto, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Taniuchi
authors.affiliation: Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Kyoto, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Tsuchiya
authors.affiliation: Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Kyoto, Japan.
authors.forename: Utako
authors.initials: U
authors.lastname: Kato
authors.affiliation: Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Kyoto, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Hara
authors.affiliation: Lipid Biology Laboratory, RIKEN, Wako, Saitama, Japan.
authors.forename: Takehiko
authors.initials: T
authors.lastname: Inaba
authors.affiliation: Lipid Biology Laboratory, RIKEN, Wako, Saitama, Japan.
authors.forename: Toshihide
authors.initials: T
authors.lastname: Kobayashi
authors.affiliation: Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Kyoto, Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Sasaki
authors.affiliation: Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Kyoto, Japan.
authors.forename: Kazunari
authors.initials: K
authors.lastname: Akiyoshi
authors.affiliation: Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, Kyoto, Japan.
authors.forename: Miho
authors.initials: M
authors.lastname: Watanabe-Takahashi
authors.affiliation: Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, Kyoto, Japan.
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Nishikawa
authors.affiliation: Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Kyoto, Japan.
authors.forename: Masato
authors.initials: M
authors.lastname: Umeda
mesh_terms: D019943:Amino Acid Substitution / Q000502:physiology; D006860:Hydrogen Bonding; D007700:Kinetics; D008566:Membranes / Q000378:metabolism; D019151:Peptide Library; D010455:Peptides / Q000378:metabolism*; D010712:Phosphatidic Acids / Q000378:metabolism*; D055672:Static Electricity; D014364:Tryptophan / Q000378:metabolism
chemical_list: D019151:Peptide Library; D010455:Peptides; D010712:Phosphatidic Acids; D014364:Tryptophan