Department of Food Science, Massachusetts Agricultural Experiment Station, University of Massachusetts, Amherst, MA 01003, USA.
Int J Mol Sci. 2014 Jan 10;15(1):944-57. doi: 10.3390/ijms15010944.
A thermophilic fungus previously isolated from composted horse manure was found to produce extracellular iso-RNases that were purified 127.6-fold using a combination of size exclusion chromatography and a novel affinity membrane purification system. The extent of purification was determined electrophoretically using 4%-15% gradient polyacrylamide gels. RNase activity was dependent on the presence of a metal co-factor with significantly more activity with Zn2+ or Mn2+ than Mg2+. The RNases exhibited maximum activity at both pH 3.0 and pH 7.0 with no activity at pH 2.0 or 10.0. The optimal temperature for the iso-RNase was 70 °C. The molecular weight of the iso-RNase was determined to be 69 kDa using a Sephadex G-75 column.
从堆肥马粪中分离到的一种嗜热真菌被发现能产生细胞外的同工 RNase，通过大小排阻色谱法和一种新型亲和膜纯化系统的组合，同工 RNase 被纯化了 127.6 倍。电泳法用于确定纯化程度，使用 4%-15%梯度聚丙烯酰胺凝胶。RNase 活性依赖于金属辅因子的存在，Zn2+或 Mn2+的活性显著高于 Mg2+。RNases 在 pH 3.0 和 pH 7.0 时均表现出最大活性，而在 pH 2.0 或 10.0 时则无活性。同工 RNase 的最适温度为 70°C。使用 Sephadex G-75 柱，同工 RNase 的分子量被确定为 69 kDa。
