title: A thermal hysteresis-producing xylomannan glycolipid antifreeze associated with cold tolerance is found in diverse taxa.
abstract: The presence of large-molecular-mass, thermal hysteresis (TH)-producing antifreezes (e.g., antifreeze proteins) has been reported in numerous and diverse taxa, including representative species of fish, arthropods, plants, fungi, and bacteria. However, relatively few of these antifreeze molecules have been chemically characterized. We screened diverse species by subjecting their homogenates to ice-affinity purification and discovered the presence of a newly identified class of antifreeze, a xylomannan-based TH-producing glycolipid that was previously reported in one species of freeze-tolerant Alaskan beetle. We isolated xylomannan-based antifreeze glycolipids from one plant species, six insect species, and the first frog species to be shown to produce a large-molecular-mass antifreeze. (1)H NMR spectra of the ice-purified molecules isolated from these diverse freeze-tolerant and freeze-avoiding organisms were nearly identical, indicating that the chemical structures of the glycolipids were highly similar. Although the exact functions remain uncertain, it appears that antifreeze glycolipids play a role in cold tolerance.
authors.affiliation: Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA. kwalte2@life.illinois.edu
authors.forename: Kent R
authors.initials: KR
authors.lastname: Walters
authors.forename: Anthony S
authors.initials: AS
authors.lastname: Serianni
authors.forename: Yann
authors.initials: Y
authors.lastname: Voituron
authors.forename: Todd
authors.initials: T
authors.lastname: Sformo
authors.forename: Brian M
authors.initials: BM
authors.lastname: Barnes
authors.forename: John G
authors.initials: JG
authors.lastname: Duman
mesh_terms: D000064:Acclimatization / Q000502:physiology*; D000818:Animals; D021301:Antifreeze Proteins / Q000737:chemistry*; D001517:Coleoptera / Q000737:chemistry; D003451:Cryoprotective Agents / Q000302:isolation & purification*; D006017:Glycolipids / Q000737:chemistry*; D007313:Insecta / Q000737:chemistry; D008351:Mannans / Q000737:chemistry*; D019906:Nuclear Magnetic Resonance, Biomolecular; D011898:Ranidae / Q000378:metabolism; D032322:Solanum / Q000737:chemistry
chemical_list: D021301:Antifreeze Proteins; D003451:Cryoprotective Agents; D006017:Glycolipids; D008351:Mannans