Type II antifreeze protein from a mid-latitude freshwater fish, Japanese smelt (Hypomesus nipponensis).
A lot of reports of antifreeze protein (AFP) from fish have been published, but no report has mentioned of commercialized mid-latitude fresh water fish which producing AFP in its body fluid. We found that the AFP in the body fluid of Japanese smelt (Hypomesus nipponensis) from mid-latitude fresh water was purified and characterized. The N-terminal amino acid sequence of the Japanese smelt AFP was 75.0% identical to Type II AFP from herring. Results of EDTA treatment and ruthenium red staining suggested that the Japanese smelt AFP had at least one Ca2+-binding domain. Interestingly, the antifreeze activity of the Japanese smelt AFP did not completely disappear when Ca2+ ions were removed. The molecular mass of the Japanese smelt AFP was calculated to be 16,756.8 by the TOF-mass analysis. The Open reading flame of the gene coding for the Japanese smelt AFP was 444 bp long and was 85.0% identical with the entire herring AFP gene. The cDNA and amino acid sequence of the Japanese smelt AFP were the same length as those of herring AFP.
Yamashita
Yasuhiro
Y
Department of Biotechnology, Faculty of Engineering, Kansai University, 3-3-35 Yamate-cho, Suita, Osaka 564-8680, Japan. yy529@mb.dreammail.ne.jp
Miura
Rikako
R
Takemoto
Yukari
Y
Tsuda
Sakae
S
Kawahara
Hidehisa
H
Obata
Hitoshi
H
D000595:Amino Acid Sequence; D000818:Animals; D021341:Antifreeze Proteins, Type II / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D001483:Base Sequence; D002118:Calcium / Q000378:metabolism; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D005618:Fresh Water; D013058:Mass Spectrometry / Q000379:methods; D008969:Molecular Sequence Data; D036441:Osmeriformes / Q000235:genetics* / Q000378:metabolism; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D016364:Reading Frames / Q000235:genetics; D012430:Ruthenium Red / Q000737:chemistry; D017386:Sequence Homology, Amino Acid
D021341:Antifreeze Proteins, Type II; D018076:DNA, Complementary; D012430:Ruthenium Red; D002118:Calcium