Nanoparticle Assembly and Gelatin Binding Mediated by Triple Helical Collagen Mimetic Peptide

Abstract

Peptide-conjugated nanoparticles (NPs) have promising potential for applications in biosensing, diagnosis, and therapeutics because of their appropriate size, unique self-assembly, and specific substrate-binding properties. However, controlled assembly and selective target binding are difficult to achieve with simple peptides on NP surfaces because high surface energy makes NPs prone to self-aggregate and adhere nonspecifically. Here, we report the self-assembly and gelatin binding properties of collagen mimetic peptide (CMP) conjugated gold NPs (CMP-NPs). We show that the orientation of CMPs displayed on the NP surface can control NP assembly either by promoting or hindering triple helical folding between CMPs of neighboring NPs. We also show that CMP-NPs can specifically bind to denatured collagen by forming triple-helical hybrids between denatured collagen strands and CMPs, demonstrating their potential use for detection and selective removal of gelatin from protein mixtures. CMP conjugated NPs offer a simple and effective method for NP assembly and for targeting denatured collagens with high specificity. Therefore, they may lead to new types of functional nanomaterials for detection and study of denatured collagen associated with diseases characterized by high levels of collagen degradation.

Molecular assessment of collagen denaturation in decellularized tissues using a collagen hybridizing peptide

“…To verify whether these detergent-modified collagen structures contain denatured collagen molecules, we probed the TEM samples with gold nanoparticles that have CHPs on their surface (designed as CHP-NP). Previously using TEM, we demonstrated that CHP-NPs bind to both thermally denatured [ 42 ] and mechanically damaged collagen molecules (unpublished results) by triple-helical hybridization. Here we found high densities of collagen-bound CHP-NPs in the samples subjected to heating, 1% SDS, and 3% Triton X-100, whereas only a few NPs could be seen in the native collagen sample, as well as in samples subject to 8 mM CHAPS and 4% SD ( Fig.…”

“…The CHP with an N-terminal acetylated cysteine [C-GGG-(GPO) 9 ] was synthesized, purified and heated at 80 °C for 5 min followed by addition to a solution of citrate-stabilized gold nanoparticle (NP), as described previously [ 42 ]. The mixture was incubated overnight at room temperature.…”

Molecular level detection and localization of mechanical damage in collagen enabled by collagen hybridizing peptides

“…TEM has long been used to interrogate the integrity of collagen fibrils through visualization of the characteristic 67 nm periodic d-banding pattern35. Previously using TEM, we demonstrated that NP-CHP binds to thermally denatured collagen molecules by triple-helical hybridization36. An unloaded fascicle and a fascicle stretched to 12% strain were treated with NP-CHP, washed and imaged by TEM.…”

Squid-Inspired Tandem Repeat Proteins: Functional Fibers and Films

“…The GPX repeat forms left-handed α-helices that intertwine into right-handed triple helices (Kadler et al, 2007; Fratzl, 2008). Recombinant hydroxyproline (Luo and Tong, 2011) collagen has been synthetized for tissue engineering (e.g., corneal substitution, cartilage replacement) as well as biosensing and therapeutics applications (Toman et al, 2000; Teles et al, 2010; San et al, 2016).…”