title: Isolation and characterization of type I antifreeze proteins from Atlantic snailfish (Liparis atlanticus) and dusky snailfish (Liparis gibbus).
abstract: Antifreeze proteins (AFPs) were isolated from the blood plasma of Atlantic snailfish Liparis atlanticus and dusky snailfish Liparis gibbus, which belong to the Teleost family Cyclopteridae, a close relative of sculpins. Using a combination of gel filtration chromatography and reversed-phase HPLC, proteins were purified to individual peaks. Atlantic snailfish plasma contained two different proteins (MW=9344, 9415) while dusky snailfish plasma contained five protein isoforms (MW=9514-9814), as determined by mass spectrometry. Further characterization revealed that these proteins are rich in alanine (>50 mol%), and have alpha-helical secondary structure that can undergo reversible thermal denaturation. Thermal hysteresis activities of these proteins were similar to each other but lower than the major type I AFPs from winter flounder. Results of this study have indicated that although the AFPs from snailfish are significantly larger than previously described type I AFPs, they share enough characteristics to be classified in this group.
authors: Ocean Sciences Centre, Memorial University of Newfoundland, A1C 5S7, St. John's, NF, Canada. evans@mun.ca
authors: R P
authors: RP
authors: Evans
authors: G L
authors: GL
authors: Fletcher
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D000818:Animals; D021322:Antifreeze Proteins, Type I / Q000737:chemistry* / Q000302:isolation & purification; D001267:Atlantic Ocean; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D002942:Circular Dichroism; D003080:Cold Temperature; D004591:Electrophoresis, Polyacrylamide Gel; D005399:Fishes / Q000097:blood*; D008969:Molecular Sequence Data; D017433:Protein Structure, Secondary; D012621:Seasons
chemical_list: D000596:Amino Acids; D021322:Antifreeze Proteins, Type I