杨尺蠖核型多角体病毒蛋白质的特性

本文研究了杨尺蠖核型多角体病毒(AciNPV)蛋白质特性,用反复调等电点法,从AciNPV的多角体蛋白中分离到A,B两种蛋白,Sepharose 6B柱层析和超离心沉降分析表明,两者均为一个峰纯,沉降系数(S20w)分别为4.9和8.9,对A蛋白进行了16种氨基酸组成分析,Glu、Asp和Leu含量高于其它氨基酸,不含Cys,用SDS-聚丙烯酰胺凝胶电泳和免疫双扩散法分析表明,用两倍体积饱和硫酸铵沉淀法制备的多角体蛋白,与提纯的多角体A、B蛋白之间无差异,多角体蛋白结构多肽由6种组成,分子量在12500—54000道尔顿范围内,其中32000是多角体蛋白的主要多肽,病毒粒子结构多肽和核衣壳蛋白分别由19和7个多肽组成,分子量范围分别在89000～13000和34000～13000之间,间接试验结果表明,在AciNPV中有碱性蛋白酶活性存在。

A STUDY ON THE PROTEINS OF NUCLEAR POLYHEDROSIS VIRUS OF POPLAR LOOPER, APOCHEIMA CINERARIUS

The polyhedrons proteins A and B were isolated by repeated adjustment of isoelectric points from the polyhedra of nuclear polyhedrosis virus of pop. lar looper, Apocheima cinerarius, and were identified as a single peak with Sepharose 6B colum chromatography and ultracentrifugal sedimentation respectively. The sedimentation coefficient of protein A and B were found to be about 4.9 and 8.9 (S20w) respectively. Protein A plus B on analysis with Sepharose 6B colum chromatography showed two peaks. The analysis of amino acid composition of protein A showed that the amount of several amino acids such as Glu, Asp and Leu was higher than others. The N-po-lyhedron ( N-P ) protein that was separated by salting out with 2 volumes of saturated ammonium sulfate solution and protein A and B were com-paraed by SDS-polyacrylamide gel electrophoresis and immunodiffusion methods No difference in their polypeptide patterns and immunoreaction were observed. The polypeptides of polyhedrin protein consisted of six bands with molecular weights of 54 000 to 12 500, and 32000 band was the major polypeptide. Virions and nucleocapsids consisted of 19 and 7 bands with molecular weights ranging from 89000 to 13000 and 34000 to 13000 respectively. Indirect test result showed that there was a kind alkaline protease activity associated with the nuclear polyhedrosis virus of Apocheima cinerarius.