title: Molecular characterization of vitellin from the ovaries of the white shrimp Penaeus (Litopenaeus) vannamei.
abstract: Vitellin (Vt) was purified from ovary extracts of mature females of the white shrimp Penaeus vannamei using Sepharose CL-4B and Q-Sepharose columns. Native Vt had an apparent molecular weight of 388 kDa as detected in Native-PAGE, bound the lipophilic dye Oil Red O and had a total lipid content of approximately 43.8%. Under reducing and denaturing conditions (SDS-PAGE), Vt is composed of three major subunits of 87, 78 and 46 kDa, although minor bands of 65, 61 and 31 kDa are also detected. The 87- and 78-kDa polypeptides were strongly recognized by Penaeus semisulcatus anti-Vt polyclonal and Penaeus monodon anti-Vt monoclonal antibodies. Furthermore, the N-terminal amino acid sequence of the 78-kDa polypeptide is very similar to Penaeus japonicus vitellogenin (Vg) and P. semisulcatus Vt, with an identity of 76%. Circular dichroism indicates that the beta-helix content of Vt is 25% while beta-sheets correspond to 37 and 14% of unordered secondary structure. These values are similar to insect microvitellogenin. Vt has an emission fluorescence maximum at 329 nm, comparable to the shrimp high-density lipoprotein/beta-glucan binding protein (HDL/BGBP).
authors.affiliation: Marine Biotechnology, Centro de Investigación en Alimentación y Desarrollo, PO Box 1735 Hermosillo Son, 83000 Mexico.
authors.forename: Karina D
authors.initials: KD
authors.lastname: García-Orozco
authors.forename: Francisco
authors.initials: F
authors.lastname: Vargas-Albores
authors.forename: Rogerio R
authors.initials: RR
authors.lastname: Sotelo-Mundo
authors.forename: Gloria
authors.initials: G
authors.lastname: Yepiz-Plascencia
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002942:Circular Dichroism; D004527:Egg Proteins / Q000737:chemistry* / Q000276:immunology / Q000302:isolation & purification; D005260:Female; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010053:Ovary / Q000737:chemistry*; D033561:Penaeidae / Q000737:chemistry*; D017433:Protein Structure, Secondary; D017385:Sequence Homology; D013050:Spectrometry, Fluorescence; D014819:Vitellogenins / Q000737:chemistry* / Q000276:immunology / Q000302:isolation & purification
chemical_list: D004527:Egg Proteins; D014819:Vitellogenins