Non-covalent peptide

Deshayes S, Morris M, Heitz F, et al. Delivery of proteins and nucleic acids using a non-covalent peptide-based strategy. Adv Drug Deliv Rev 2008 60(4-5) 537-547. 

Crombez L, Charnet A, Morris MC, Aldrian-Herrada G, Heitz F, Divita G. A non-covalent peptide-based strategy for siRNA delivery. Biochem Soc Trans 2007 35 44-46. 

WieduwUd R, Tsurkan M, Chwalek K, Murawala P, Nowak M, Freudenberg U, Neinhuis C, Werner C, Zhang Y (2013) Minimal peptide motif for non-covalent peptide-heparin hydrogels. J Am Chem Soc 135 2919-2922. doi 10.1021/ja312022u... 

The covalent chemistry of peptide-functionalized CNTs has made significant progress mainly in the biomedical applications mentioned above [151-153]. In contrast, non-covalent peptide chemistry of CNTs has been rather limited. In 2003, peptide sequences with specific affinity for various kinds of CNTs,... 

Woolfson and Mahmoud have classified the routes to preparation of decorated self-assembling peptide materials [53] as (1) co-assembly, where the functional part is already attached to a self-assembling component prior to assembly, and (2) postassembly, where a non-functionahsed self-assembled structure is modified by covalent or non-covalent means. This discussion adheres to this classification. A third route, beyond the scope of this review, is the use of structured peptides as templates for inorganic materials. Section 4.1 discusses functionalised self-assemblies formed from co-assembly-type approaches, while post-assembly modifications of self-assembled structures are considered in Sect. 4.2. 

Several classes of non-covalent substrate based inhibitors have been reported, and are grouped below based on the nature of the C-terminal group interacting with the catalytic triad of the enzyme. The majority of the reported inhibitors are based on the N-terminal product of a modified substrate of the NS5A/5B cleavage side or to a lesser extent of the NS4A/4B substrate peptide. 

The past 3 years have seen tremendous advances in both the design of Cat K inhibitors and in our understanding of the effect of Cat K inhibition on bone remodeling. The structural diversity of Cat K inhibitors has expanded considerably from simple peptidomimetics to non-peptidic derivatives and even non-covalent inhibitors. The potency, selectivity and pharmacokinetic properties of key compounds are very attractive and seem well-suited to further development. The disclosure of clinical validation of the effect of Cat K inhibition on bone mineral density, plus the provocative data suggesting a decoupling of bone resorption and bone formation provides a compelling framework for further development of Cat K inhibitors for the treatment of osteoporosis. 

CNTs can be functionalized with protein via non-covalent bond (Li et al., 2005 Kim et al., 2003 Mitchell et al., 2002). For example, (beta-lactamase I, that can be immobilized inside or outside CNTs, doesn t change enzyme s activity (Vinuesa and Goodnow, 2002). Taq enzyme can attach to the outside of CNT, and doesn t change its activity (Cui et al., 2004). Peptide with Histidine and Tryptophan can have selective affinity for CNT(Guo et al., 1998). Monoclonal antibody can attach to SWNTs. Protein-modified CNTs can be used to improve its biocompatibility and biomolecular recognition capabilities (Um et al., 2006). For example, CNTs functionalized with PEG and Triton X-100 can prevent nonspecific binding of protein and CNTs. Biotin moiety is attached to the PEG chains Streptavidin can bind specifically with biotin-CNT (Shim et al., 2002). 

Capillary coating can also stabilize the migration times and resolutions. This is in particular necessary in the case of peptide and protein analysis, because proteins tend to stick to capillary walls. Often low-concentration polyethylene oxide solutions are recommended as well as dynamic bilayer coating formed by a non-covalent adsorption of polybrene and polyvinylsulfonate (PVS). Due to the stability of the EOF, the variation of intra- and intercapillary migration time was less than 1% relative standard deviation (RSD) with basic analytes and peptides. 

Kempe M, Mosbach K. Chiral recognition of N alpha-protected amino acids and derivatives in non-covalently molecularly imprinted polymers. Int J Peptide Protein Res 1994 44 603 -606. 

Sami-Manchado, P. and Cheynier, V., Study of non-covalent complexation between catechin derivatives and peptides by electrospray ionization mass spectrometry, J. Mass Spectrom., 37, 609, 2002. 

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