Noncoded amino acids in protein engineering: Structure-activity relationship studies of hirudin-thrombin interaction
Research article published in Biotechnology and applied biochemistry (2018)
Abstract
The advent of recombinant DNA technology allowed to site-specifically insert, delete, or mutate almost any amino acid in a given protein, significantly improving our knowledge of protein structure, stability, and function. Nevertheless, a quantitative description of the physical and chemical basis that makes a polypeptide chain to efficiently fold into a stable and functionally active conformation is still elusive. This mainly originates from the fact that nature combined, in a yet unknown manner, different properties (i.e., hydrophobicity, conformational propensity, polarizability, and hydrogen bonding capability) into the 20 standard natural amino acids, thus making difficult, if not impossible, to univocally relate the change in protein stability or function to the alteration of physicochemical properties caused by amino acid exchange(s). In this view, incorporation of noncoded amino acids with tailored side chains, allowing to finely tune the structure at a protein site, would facilitate to dissect the effects of a given mutation in terms of one or a few physicochemical properties, thus much expanding the scope of physical organic chemistry in the study of proteins. In this review, relevant applications from our laboratory will be presented on the use of noncoded amino acids in structure-activity relationships studies of hirudin binding to thrombin.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
Noncoded amino acids in protein engineering: Structure-activity relationship studies of hirudin-thrombin interaction.
Why This Matters for Hirudotherapy
This review summarizes the authors' laboratory work using noncoded amino acids with tailored side chains to conduct structure-activity relationship studies of hirudin binding to thrombin, aiming to dissect how individual physicochemical properties—such as hydrophobicity, hydrogen bonding, or conformational propensity—contribute to the interaction. For ASH and hirudotherapy, this work is directly relevant because hirudin is the principal anticoagulant in medicinal leech saliva and the mechanistic basis of its potent thrombin inhibition underlies the therapeutic action of leech therapy and related direct thrombin inhibitors. A precise molecular understanding of hirudin-thrombin binding could help guide rational optimization of leech-derived anticoagulants. An honest caveat is that this is a review of protein-engineering and biophysical studies, not a clinical or in vivo investigation; it provides no efficacy, safety, or therapeutic-outcome data, and it does not constitute proof of clinical benefit for hirudotherapy.
Citation
Noncoded amino acids in protein engineering: Structure-activity relationship studies of hirudin-thrombin interaction
De Filippis V et al. · Biotechnology and applied biochemistry, 2018
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