title: Purification and characterization of vitellin-2 from the ovary of the American cockroach, Periplaneta americana.
abstract: Two vitellins (Vn-1 and Vn-2) were identified in cockroach ovary. Vn-2 was purified by ion-exchange chromatography using DEAE cellulose and Sepharose CL-6B, and gel filtration using Sephadex G-200 and Sepharose 4B. Vn-2 comprises three subunits with molecular weights of 102, 72 and 40 kDa. Vn-2 contains diacylglycerol and triacylglycerol; their fatty acids are mostly lauric acid and palmitoleic acid. Vn-2 also has phosphatidylcholine and phosphatidylethanolamine but no sphingomyelin. Vn-2 contains large amounts of glutamic acid and aspartic acid but small amounts of tyrosine, phenylalanine, and methionine. Vn-2 gradually decreases during embryonic development; none remains in first instar larvae. It was found that Vn-2 partially reacted immunologically with ovarian extracts of Periplaneta fulginosa but not with those of Blattella germanica. Vn-2 also showed no immunological reaction with extracts from other orders; including Cletus schmidti (Hemiptera), Lucilia illustris (Diptera), Anechura japonica (Dermaptera), Bombyx mori (Lepidoptera), and Ducetia japonica (Orthoptera).
authors.affiliation: Department of Biology, Korea University, Seoul, Korea.
authors.forename: H R
authors.initials: HR
authors.lastname: Kim
authors.forename: S D
authors.initials: SD
authors.lastname: Lee
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000818:Animals; D003429:Cross Reactions; D004527:Egg Proteins / Q000737:chemistry / Q000276:immunology / Q000302:isolation & purification*; D005260:Female; D006458:Hemolymph / Q000737:chemistry; D007120:Immunochemistry; D007313:Insecta; D008055:Lipids / Q000032:analysis; D008970:Molecular Weight; D010053:Ovary / Q000737:chemistry*; D010526:Periplaneta / Q000737:chemistry* / Q000254:growth & development; D011487:Protein Conformation; D013045:Species Specificity
chemical_list: D000596:Amino Acids; D004527:Egg Proteins; D008055:Lipids