Abstract
Introducing one or more intramolecular thioether bridges in a peptide provides a promising approach to create more stable molecules with improved pharmacodynamic properties and especially to protect peptides against proteolytic degradation. Lanthipeptides are compounds that naturally possess thioether bonds in their structure. The model lanthipeptide, nisin, is produced by Lactococcus lactis as a core peptide fused to a leader peptide. The modification machinery responsible for nisin production, including the Ser/Thr-dehydratase NisB and the cyclase NisC, can be applied for introducing a thioether bridge into peptides fused to the nisin leader peptide, e.g., to replace a disulfide bond. Vasopressin plays a key role in water homeostasis in the human body and helps to constrict blood vessels. There are two cysteine residues in the structure of wild type vasopressin, which form a disulfide bridge in the mature peptide. Here, we show it is possible to direct the biosynthesis of vasopressin variants in such a way that the disulfide bridge is replaced by a thioether bridge using the nisin modification machinery NisBTC, albeit at low efficiency. Vasopressin mutants were fused either to the nisin leader peptide directly (Type A), after the first three rings of nisin (Type B/C), or after full nisin (Type D). The type B strategy was optimal for expression. LC-MS/MS data verified the formation of a thioether bridge, which provides proof of principle for this modification in vasopressin. This is a first step prior to the necessary increase of the production yield and further purification of these peptides to finally test their biological activity in tissue and animal models.
Highlights
Vasopressin, a neurohypophysial hormone, was originally detected by Oliver and Schäfer (1895), who demonstrated that extracts of the pituitary gland altered blood pressure
In order to make this peptide amenable for the nisin modification machinery, the first Cys was mutated into Ser, generating the sequence “SYFQNCPRG.” This vasopressin mutated sequence was fused at the end of either full nisin or truncations thereof (Figure 1), inserting in each case a cleavage site for several different peptidases and chemical reagents that can facilitate the release of this hormone
Due to the interest of vasopressin and related peptide hormones and the stabilizing effect of cyclization, in our work, a thioether bridge was introduced into vasopressin using the nisin modification machinery in order to create improved and more stable vasopressin variants
Summary
Vasopressin, a neurohypophysial hormone, was originally detected by Oliver and Schäfer (1895), who demonstrated that extracts of the pituitary gland altered blood pressure. Vasopressin was isolated and its properties were further investigated (Vigneaud, 1952). Mammalian vasopressin was reported to be produced primarily within the hypothalamic area and released or projected to various brain regions in response to stress, sexual stimulation, uterine dilatation, and dehydration (Donaldson and Young, 2008; Insel, 2010). Vasopressin is used in medicine for different treatments including diabetes insipidus, vasodilatory shock, and gastrointestinal bleeding. The half-life of vasopressin is 16–24 min (Czaczkes et al, 1964; Baumann and Dingman, 1976), to other peptide hormones (de Vries et al, 2010)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
