title: Engineered knottin peptides as diagnostics, therapeutics, and drug delivery vehicles.
abstract: Inhibitor cystine-knots, also known as knottins, are a structural family of ultra-stable peptides with diverse functions. Knottins and related backbone-cyclized peptides called cyclotides contain three disulfide bonds connected in a particular arrangement that endows these peptides with high thermal, proteolytic, and chemical stability. Knottins have gained interest as candidates for non-invasive molecular imaging and for drug development as they can possess the pharmacological properties of small molecules and the target affinity and selectively of protein biologics. Naturally occurring knottins are clinically approved for treating chronic pain and GI disorders. Combinatorial methods are being used to engineer knottins that can bind to other clinically relevant targets in cancer, and inflammatory and cardiac disease. This review details recent examples of engineered knottin peptides; their use as molecular imaging agents, therapeutics, and drug delivery vehicles; modifications that can be introduced to improve peptide folding and bioactivity; and future perspectives and challenges in the field.
authors.affiliation: Department of Bioengineering, Stanford University, United States.
authors.forename: James R
authors.initials: JR
authors.lastname: Kintzing
authors.affiliation: Department of Bioengineering, Stanford University, United States; Department of Chemical Engineering, Stanford University, United States. Electronic address: jennifer.cochran@stanford.edu.
authors.forename: Jennifer R
authors.initials: JR
authors.lastname: Cochran
mesh_terms: D000818:Animals; D057771:Cystine-Knot Miniproteins / Q000737:chemistry*; D003933:Diagnosis; D004337:Drug Carriers; D006801:Humans; D010455:Peptides / Q000737:chemistry*; D015202:Protein Engineering; D013812:Therapeutics
chemical_list: D057771:Cystine-Knot Miniproteins; D004337:Drug Carriers; D010455:Peptides