粘虫颗粒体病毒增效因子的分离纯化及其生化性质

粘虫颗粒体病毒经０．０２ｍｏｌ／ＬＮａＯＨ碱溶，先用ＳｅｐｈａｄｅｘＧ－２００凝胶过滤层析柱从病毒蛋白粗提中分离增效因子，然后选用ＤＥＡＥ－ＳｅｐｈａｒｏｓｅＣＬ－６Ｂ离子交换层析柱进一步纯化增效因子，得到少量电泳纯的增效因子蛋白样品。

PURIFICATION AND BIOCHEMICAL CHARACTERIZATION OF SYNERGETIC FACTOR IN THE CAPSULE OF A GRANULOSIS VIRUS OF THE ARMYWORM, PSEUDALETIA UNIPUNCTA

The Hawaiian strain of Pseudaletia unipuncta GV was propagated in Pseudaletia separata larvae. The capsules of PuGV were dissolved in 0.02mol/L NaOH, the concentrated crude protein extract was firstly filtered through on a column of Sephadex G-200, the fraction mainly containing synergetic factor was further purified by applying onto a DEAE-Sepharose CL-6B column. The purified synergetic factor has typical ultraviolet absorptive spectrum of proteins and the wavelength, at which synergetic factor has maximum absorbance, is 275.2nm. Determined by SDS-PAGE, the molecular weight of synergetic factor is 108kD. Following native-PAGE, Sudan Black B staining method and Periodic acid-Schiff method were used to detect lipoprotein and protein-bound carbohydrates respectively, but the bands of synergetic factor had negative reactions. The isoelectric point of synergetic factor is pH5.3 analyzed by polyacrylamide gel isoelectric focusing. The results of amino acid analysis indicated that 26.42% of the purified synergetic factor consists of the acidic amino acids, aspartic and glutamic acids.