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.
Department of Biotechnology, Faculty of Engineering, Kansai University, 3-3-35 Yamate-cho, Suita, Osaka 564-8680, Japan. yy529@mb.dreammail.ne.jp
Yasuhiro
Y
Yamashita
Rikako
R
Miura
Yukari
Y
Takemoto
Sakae
S
Tsuda
Hidehisa
H
Kawahara
Hitoshi
H
Obata
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