Purification and characterization of α2-macroglobulin from the white shrimp (Penaeus vannamei)
2003; Elsevier BV; Volume: 134; Issue: 4 Linguagem: Inglês
10.1016/s1532-0456(03)00002-4
ISSN1878-1659
AutoresTeresa Gollas‐Galván, Rogerio R. Sotelo‐Mundo, Glória Yépiz-Plascencia, Claudia Vargas-Requena, Francisco Vargas‐Albores,
Tópico(s)Insect Utilization and Effects
Resumoalpha(2)-Macroglobulin (alpha(2)M) is a broad-spectrum protease-binding protein abundant in plasma from vertebrates and several invertebrate phyla. This protein was purified from cell-free hemolymph of the white shrimp, Penaeus vannamei, using Blue-Sepharose and Phenyl-Sepharose chromatography. The shrimp alpha(2)M is a 380 kDa protein, a homodimer of two apparently identical subunits of approximately 180 kDa linked by disulphide bridges. The amino acid sequence of the N-terminus is similar to the Limulus alpha(2)M counterpart. The shrimp alpha(2)M has a wide inhibition spectrum against different proteinase types including trypsin, leucine amino peptidase, chymotrypsin, elastase and papain. The secondary structure of shrimp alpha(2)M is mainly beta-sheet (36%), with a characteristic minimum elipticity at 217 nm. Evidence for a thiolester-mediated inhibition mechanism of proteases by alpha(2)M was provided by inactivation with methylamine.
Referência(s)