Nicolas E, Beggs J M, Haltiwanger B M, Taraschi T F
Department of Pathology, Anatomy and Cell Biology, Jefferson Medical College, Philadelphia, PA 19107, USA.
FEBS Lett. 1997 Apr 7;406(1-2):162-4. doi: 10.1016/s0014-5793(97)00267-6.
Several plant ribotoxins, including gelonin, were reported to have additional weak nuclease activities on supercoiled DNA. The potential contribution of this activity to their cytotoxicity has not been given serious consideration due to concerns about contaminating nucleases in the protein preparations. We now report the degradation of single-stranded DNA by preparations of native plant gelonin and recombinant gelonin produced in E. coli. The DNase activity of both preparations is similarly modulated by zinc. An SDS-PAGE DNase assay identifies gelonin as the polypeptide responsible for deoxyribonuclease activity.
据报道，包括去糖链蛋白在内的几种植物核糖体毒素对超螺旋DNA具有额外的微弱核酸酶活性。由于担心蛋白质制剂中存在核酸酶污染，这种活性对其细胞毒性的潜在贡献尚未得到认真考虑。我们现在报道了天然植物去糖链蛋白制剂和在大肠杆菌中产生的重组去糖链蛋白对单链DNA的降解作用。两种制剂的DNA酶活性都受到锌的类似调节。SDS-PAGE DNA酶分析确定去糖链蛋白是负责脱氧核糖核酸酶活性的多肽。
