Purification and Characterization of Iso-Ribonucleases from a Novel Thermophilic Fungus

International Journal of Molecular Sciences

Kyle S. Landry¹ 

[1] Department of Food Science, Massachusetts Agricultural Experiment Station, University of Massachusetts, Amherst, MA 01003, USA; E-Mail

关键词: affinity purification;    RNase purification;    chromatography;    thermophilic fungi;    RNase characterization;   

DOI  :  10.3390/ijms15010944

来源: mdpi

【 摘 要 】

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.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland