Highly Specific Affinities of Short Peptides against Synthetic Polymers

Abstract

We investigated polymer-binding 7-mer peptides that recognize differences in the polymer stereoregularity of all-purpose poly(methyl methacrylate)s (PMMAs) with simple chemical structures. Quantitative surface plasmon resonance measurements detected association/dissociation processes of the peptides against PMMA film surfaces, followed by an estimation of kinetic parameters such as association/dissociation rate constants and affinity constants. Greater association and smaller dissociation constants of the peptides were observed against a target isotactic PMMA than the structurally similar reference syndiotactic PMMA, followed by greater affinity constants against the target. A c02 peptide composed of the Glu-Leu-Trp-Arg-Pro-Thr-Arg sequence showed the greatest affinity constant (2.8x10(5) M(-1)) for the target, which was 41-fold greater than that for the reference, thus demonstrating extremely high peptide specificities. The substitution of each amino acid of the c02 peptide to Ala (Ala scanning) clearly revealed the essential amino acids for the affinity constants; the essential order was Pro5>>Thr6>Arg7>Glu1>Arg4. In fact, the shorter 4-mer peptide composed of the C-terminal Arg-Pro-Thr-Arg sequence of the c02 peptide still demonstrated strong target specificity, although the N-terminal 4-mer peptide Glu-Leu-Trp-Arg completely lost its specificity. The possible conformations modeled with Molecular Mechanics supported the significance of the Arg-Pro-Thr-Arg sequence. The thermodynamic parameters of the c02 peptide suggested an induced fit mechanism for the specific affinity. The present affinity analyses of polymer-recognizing peptides revealed significant and general information that was essential for potential applications in peptidyl nanomaterials.

Nanoliter contact angle probes tumor angiogenic ligand–receptor protein interactions

“…To this purpose we used, as a model ligand, the peptide Cyclo-VEGI, a well-known VEGFR2 antagonist (Zilberberg et al, 2003) that weights 1998 Da. In order to eliminate the possible contribution of non-specific adsorption that may occur when employing LMW molecules on biopolymer functionalized surfaces (Serizawa et al, 2007), the LMW peptide VEGF15 was used as the negative control (D'Andrea et al, 2005).…”

Surface modification of stereoregular and stereocomplex poly(methyl methacrylate) films with biologically identified peptides

“…The binding constant of the SCBP for the SC films was estimated to be 7.5Â10 5 M À1 , which was comparable with that of itBP (2.8Â10 5 M À1 ) and stBP (9.1Â10 4 M À1 ). 18 The binding specificity of SCBP for the SC films was demonstrated (see the Supplementary Information for the detailed Results and discussion). The sequence homologies of the SCBP with other identified peptides for the SC films suggested that the amino acid sequence near the C terminus was important for binding with SC.…”

Directed evolution of polypropylene and polystyrene binding peptides

“…In conclusion, our results validate the PeP evo protocol for directed evolution of PBPs. Binding peptides have further potential applications in antimicrobial coatings for biomaterials, in plant health, in assembly of nano‐inks, nanoparticles, or nanomaterials (Chiu et al, ; Meurer et al, ; Serizawa, Sawada, et al, ; Yazici et al, ). Additionally the wettability of polymer surfaces can be increased through introduction of charged amino acids which can very likely also be improved by employing the ABBA screening system.…”

“…Phage display libraries employ usually short peptides (7–12 amino acids) which are selected for binding to targeted materials (Serizawa, Matsuno, & Sawada, ). PP‐ and PS‐binding peptides were isolated from a 12‐mer library (e.g., Ph.D.‐7 library (New England Biolabs, Ipswic))(Kumada et al, ; Serizawa, Sawada, & Matsuno, ; Vodnik et al, ) and PP‐binding peptides were patented for immobilization, medical, and cosmetic applications. PS‐binding peptides PS19‐1 and PS19‐6 were shown to bind to hydrophilic PS surfaces (PS‐A plate, Animal cell culture, #3860‐096, surface treatment for tissue culture, AGC Techno Glass Co., Ltd., Shizuoka, Japan)) with a maximum adsorption of 81 mg/m 2 and 86 mg/m 2 , respectively; glutathione S‐transferase was used as reference enzyme for immobilization studies (Kumada, Kuroki, Yasui, Ohse, & Kishimoto, ).…”