长毛对虾必需氨基酸的研究

Essential Ami no Acids of the Prawn Penaeus penicillatus

分析了不同体长组的长毛对虾生化组成和必需氨基酸(EAA)的可能种类。结果表明:(1)长毛对虾的最主要生化物质蛋白质的含量似有随体长增长(40 mm至 104 mm)而升高。但糖类含量较稳定;(2)注射~3H-葡萄糖后测得 Glu,Asp,Ser,Pro,Gly,(Cys)_2和 Ala等带有较强的放射性,长毛对虾可能从葡萄糖合成这些氨基酸。而极少或甚至没有~3H 参入到Met,Thr,He,Leu,Val,Arg,His,Lys,Phe,Tyr和Trp中。这些可能是长毛对虾的EAA。

The biochemical compositions of different size P.penicillalusdetermined in this paper show that contents of animal proteins change with the body sizes and vary slightly in glycogen. Seven amino acids,i.e. glutamic acid, alanine, aspartic acid, cystjnc, glycine, proline and serinc, could be synthesied de novoby the prawn after investigating by a radio-isotopic method using (1-3H)-glucose. The constituent amino acids of the protein fractions were isolated by paper chromatography on paper Xinhua No I, with no tryphtophan examined, and then measured using Tri-carb 4 300 Liquid Scintillation Counter (Packard Iustr. Comp.USA). It shows that methionine, valine phcnylalanine, arginine, threnine, histidinc, lysine, isoleueine, leucine and tyrosine have been, little or even not, incorporated radioactivity from 3H-glucose. These amino acids are considcred to be prabably essential ones for this animal.lt also reveals that the smaller prawn synthesized more radioactivities in protein from glucose than that of bigger one.