Abstract: The aim of this study was to identify the single protein extracted from Crassostrea gigas muscle sarcoplasm by mass spectrometry and analyze the molecular weight consistency of the induced recombinant protein and the natural protein identified by western blot(WB). The consistency of the two protein on the two level structure was analyzed by cireular dichroism(CD) spectrum, and the sarcoplasmic calcium-binding protein (SCP) glycoprotein type of oyster was identified. The content of polysaccharide was also determined. The results revealed that 20 kDa protein was purified from oyster crude extract and confirmed as SCP by LC-MS / MS,the bands of natural SCP and recombinant SCP were 20 kDa and 22 kDa respectively,which including 13.5%, 18.9% and 14.5%, 18.2% Helix and Beta-Turn , respectively. SCP protein contained 7.89% O-glycosidic glycopolysaccharide. The molecular weight of recombinant SCP was slightly different from that of natural SCP, but their spatial structures were almost the same. It is a new potential allergen in Crassostrea gigas, which lays an important foundation for the study of allergenicity and sensitization mechanism of recombinant SCP instead of natural SCP in the future.
 SICHERER S H, SAMPSON H A.Food allergy:Review and update on epidemiology, pathogenesis, diagnosis, prevention and management[J].Journal of Allergy and Clinical and Immunology, 2018, 141(1):41-58.  SHARP M F, LOPATA A L.Fish Allergy:In review[J].Clinical Reviews in Allergy & Immunology,2014,46(3):258-271.  HANSON L, TELEMO E.The growing allergy problem[J].Acta Paediatrica,1997,86(9):916-918.  LIANG G Z, LI F J, HOU S B, et al.Analysis of allergens in 1625 cases[J].Practical Clinical Medicine,2005,6(7):14-16.  吴泳,黄一锦,杨萍娥.2000例过敏性疾病患者变应原检测分析[J].现代中西医结合杂志,2008,17(30):4 732-4 733. WU Y, HUANG Y J, YANG P E.Analysis of allergen detection in 2000 patients with allergic diseases[J].Modern Journal of Integrated Traditional Chinese and Western Medicine, 2008,17(30):4 732-4 733.  吕相征,刘秀梅,杨晓光.健康人群食物过敏状况的初步调查[J].中国食品卫生杂志,2005,17(2):119-121. LYU X Z, LIU X M, YANG X G.Preliminary survey on status of food allergy in young Chinese students[J].Chinese Journal of Food Hygiene, 2005,17(2):119-121.  LE T T K, NGUYEN D H, VU A T L, et al.A cross-sectional, population-based study on the prevalence of food allergies among children in two different socioeconomic regions of Vietnam[J].Pediatr Allergy and Immunology,2019, 30:348-355.  LEUNG P S C, CHOW W K, DUFFEY S, et al.IgE reactivity against a cross-reactive allergen in Crustacea and Mollusca:Evidence for tropomyosin as the common allergen[J].Journal of Allergy and Clinical Immunology,1996,98(5):954-961.  AYUSO R, LEHRER S B, REESE G.Identification of continuous, allergenic regions of the major shrimp allergen Pen a 1 (tropomyosin)[J].International Archives of Allergy and Immunology,2002,127(1):27-37.  CHEN H L, MAO H Y, CAO M J, et al.Purification, physicochemical and immunological characterization of arginine kinase, an allergen of crayfish (Procambarus clarkii)[J].Food and Chemical Toxicology,2013,62:475-484.  AYUSO R, GRISHINA G, BARDINA L, et al.Myosin light chain is a novel shrimp allergen, Lit v 3[J].Journal of Allergy and Clinical Immunology,2008,122(4):795-802.  XIA F, LI M S, LIU Q M, et al.Crystal structure analysis and conformational epitope mutation of triosephosphate isomerase, a mud crab allergen[J].Journal of Agricultural and Food Chemistry,2019,67(46):12 918-12 926.  SHIOMI K, SATO Y, HAMAMOTO S, et al.Sarcoplasmic calcium-binding protein:Identification as a new allergen of the black tiger shrimp Penaeus monodon[J].International Archives of Allergy and Immunology,2008,146(2):91-98.  LEUNG P S, CHU K H.cDNA cloning and molecular identification of the major oyster allergen from the Pacific oyster Crassostrea gigas[J].Clinical and Experimental Allergy,2001,31(8):1 287-1 294.  HERMANN A, COX J A.Sarcoplasmic calcium-binding protein[J].Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology,1995,111(3):337-345.  PASCALM, GRISHIA G, YANG A C, et al.Molecular diagnosis of shrimp allergy:Efficiency of several allergens to predict clinical reactivity[J].The Journal of Allergy and Clinical Immunology:In Practice,2015,3(4):521-529.  BAUERMEISTER K, WANGORSCH A, GAROFFO L P, et al.Generation of a comprehensive panel of crustacean allergens from the North Sea Shrimp Crangon crangon[J].Molecular Immunology,2011,48(15-16):1 983-1 992.  AYUSO R, GRISHINA G, IBÁÑEZ M D, et al.Sarcoplasmic calcium-binding protein is an EF-hand-type protein identified as a new shrimp allergen[J].Journal of Allergy and Clinical Immunology,2009,124(1):114-120.  YANG Y, HU M J, JIN T C, et al.A comprehensive analysis of the allergenicity and IgE epitopes of myosinogen allergens in Scylla paramamosain[J].Clinical & Experimental Allergy,2019,49(1):108-119.  MOSER M, CRAMERI R, BRUST E, et al.Diagnostic value of recombinant Aspergillus fumigatus allergen I/a for skin testing and serology[J].Journal of Allergy and Clinical Immunology,1994,93(1):1-11.  LYNCH N R, THOMAS W R,CHUA Y, et al.In vivo biological activity of recombinant Der p II allergen of house-dust mite[J].International Archives of Allergy and Immunology,1994,105(1):70-74.  MENZ G, DOLECEK C, SCHÖNHEIT-KENN U, et al.Serological and skin-test diagnosis of birch pollen allergy with recombinant Bet v I, the major birch pollen allergen[J].Clinical & Experimental Al-lergy,1996,26(1):50-60.  沈苑. 锯缘青蟹精氨酸激酶的分离纯化、分子克隆及过敏原性研究[D].厦门:集美大学, 2010. SHEN Y.Arginine kinase from scylla serrata:Purification, cloning, expression and allergenic analysis[D].Xiamen:JiMei University, 2010.  KING T P, HOFFMAN D, LOWENSTEIN H, et al.Allergen nomenclature[J].Allergy, 1995, 50(9):765-774.  CHEN H L, CAO M J, CAI Q F, et al.Purification and characterisation of sarcoplasmic calcium-binding protein, a novel allergen of red swamp crayfish (Procambarus clarkii)[J].Food Chemistry,2013,139(1-4):213-223.  钟岩, 潘浦群, 王艳红, 等.苯酚-硫酸法测定鲜人参中多糖含量[J].时珍国医国药,200819(8):1 957-1 958. ZHONG Y, PAN P Q, WANG Y H, et al.Determination of the content of polysaccharides in fresh root of panax ginseng by the method of phenol vitril[J].Lishizhen Medicine and Materia Medica Research,2008,19(8):1 957-1 958.  佟海菊, 张志胜, 孙克岩, 等.苯酚-硫酸法测定海湾扇贝多糖方法的研究[J].食品工业科技, 2011,32(10):447-448;452. TONG H J, ZHANG Z S, SUN K Y, et al.Study on determination of polysaccharides content in argopectens irradias by phenol-sulfuric acid method[J].Science and Technology of Food Industry, 2011,32(10):447-448;452.  HANG H C, BERTOZZI C R.The chemistry and biology of mucin-type O-linked glycosylation[J].Bioorganic & Medicinal Chemistry,2005,13(17):5 021-5 034.