title: Antifreeze glycopeptides: from structure and activity studies to current approaches in chemical synthesis.
abstract: Antifreeze glycopeptides (AFGPs) are a class of biological antifreeze agents found predominantly in Arctic and Antarctic species of fish. They possess the ability to regulate ice nucleation and ice crystal growth, thus creating viable life conditions at temperatures below the freezing point of body fluids. AFGPs usually consist of 4-55 repetitions of the tripeptide unit Ala-Ala-Thr that is O-glycosylated at the threonine side chains with β-D-galactosyl-(1 → 3)-α-N-acetyl-D-galactosamine. Due to their interesting properties and high antifreeze activity, they have many potential applications, e.g., in food industry and medicine. Current research is focused towards understanding the relationship between the structural preferences and the activity of the AFGPs, as well as developing time and cost efficient ways of synthesis of this class of molecules. Recent computational studies in conjunction with experimental results from NMR and THz spectroscopies were a possible breakthrough in understanding the mechanism of action of AFGPs. At the moment, as a result of these findings, the focus of research is shifted towards the analysis of behaviour of the hydration shell around AFGPs and the impact of water-dynamics retardation caused by AFGPs on ice crystal growth. In the field of organic synthesis of AFGP analogues, most of the novel protocols are centered around solid-phase peptide synthesis and multiple efforts are made to optimize this approach. In this review, we present the current state of knowledge regarding the structure and activity of AFGPs, as well as approaches to organic synthesis of these molecules with focus on the most recent developments.
authors.affiliation: Department of Organic and Pharmaceutical Technology, Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże St. Wyspiańskiego 29, 50-370, Wrocław, Poland.
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Urbańczyk
authors.affiliation: Department of Organic and Pharmaceutical Technology, Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże St. Wyspiańskiego 29, 50-370, Wrocław, Poland.
authors.forename: Jerzy
authors.initials: J
authors.lastname: Góra
authors.affiliation: Department of Organic and Pharmaceutical Technology, Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże St. Wyspiańskiego 29, 50-370, Wrocław, Poland. rafal.latajka@pwr.edu.pl.
authors.forename: Rafał
authors.initials: R
authors.lastname: Latajka
authors.affiliation: Organic Chemistry III, Department of Chemistry, Bielefeld University, Universitätsstrasse 25, 33615, Bielefeld, Germany. norbert.sewald@uni-bielefeld.de.
authors.forename: Norbert
authors.identifier: http://orcid.org/0000-0002-0309-2655
authors.initials: N
authors.lastname: Sewald
mesh_terms: D000818:Animals; D000864:Antarctic Regions; D021301:Antifreeze Proteins / Q000138:chemical synthesis / Q000737:chemistry* / Q000378:metabolism*; D001110:Arctic Regions; D060326:Chemistry Techniques, Synthetic; D005399:Fishes; D006031:Glycosylation; D009682:Magnetic Resonance Spectroscopy; D011487:Protein Conformation; D013329:Structure-Activity Relationship
chemical_list: D021301:Antifreeze Proteins
keywords: AFGP; Antifreeze glycopeptides; Hydration shell dynamics; Solid-phase peptide synthesis; Structure–activity relationship; Terahertz spectroscopy