Nass K, Frenkel G D
J Virol. 1980 Aug;35(2):314-9. doi: 10.1128/JVI.35.2.314-319.1980.
The adenovirus-specific DNA-binding protein was isolated from adenovirus type 5-infected KB cells and shown to possess DNase inhibitor activity. The protein decreased the rate of hydrolysis of single-strand DNA proportionately to its concentration in the reaction. Two peaks of activity were obtained upon sedimentation in a glycerol gradient, probably corresponding to the two major adenovirus-specific polypeptides in the preparation (molecular weights, 72,000 and 44,000). The DNase inhibitor activity of the adenovirus DNA-binding protein was distinguishable from that of the cellular DNA-binding protein, which we have described previously (K, Nass and G. D. Frenkel, J. Biol. Chem. 254:3407-3410, 1979), by its pattern of sedimentation and by the effect of temperature on the two activities. For the adenovirus DNA-binding protein, the ratio of DNase inhibitor activity at 43 degrees C to that at 30 degrees C was approximately 14, whereas for the cellular protein this ratio was less than 3. The DNase inhibitor activity with the temperature coefficient of 14 was absent from cells infected with adenovirus type 5 ts125 at 40 degrees C. DNase inhibition is a simple, sensitive, quantitative method for assay of the adenovirus DNA-binding protein.
腺病毒特异性DNA结合蛋白是从感染5型腺病毒的KB细胞中分离出来的，并显示具有DNA酶抑制活性。该蛋白按其在反应中的浓度成比例地降低单链DNA的水解速率。在甘油梯度中沉降时获得了两个活性峰，可能对应于制剂中的两种主要腺病毒特异性多肽（分子量分别为72,000和44,000）。腺病毒DNA结合蛋白的DNA酶抑制活性与其沉降模式以及温度对这两种活性的影响可与我们先前描述的细胞DNA结合蛋白（K. Nass和G. D. Frenkel，《生物化学杂志》254:3407 - 3410，1979）相区分。对于腺病毒DNA结合蛋白，43℃时的DNA酶抑制活性与30℃时的活性之比约为14，而对于细胞蛋白，该比例小于3。在40℃感染5型腺病毒ts125的细胞中不存在温度系数为14的DNA酶抑制活性。DNA酶抑制是一种用于检测腺病毒DNA结合蛋白的简单、灵敏的定量方法。
