Harbin Institute of Technology, School of Marine Science and Technology, Weihai 264209, China.
Molecules. 2019 Jun 14;24(12):2229. doi: 10.3390/molecules24122229.
A novel RNase R, , was cloned from the Antarctic bacterium sp. ANT206 and expressed in (). A bioinformatics analysis of the gene revealed that it contained an open reading frame of 2313 bp and encoded a protein (PsRNR) of 770 amino acids. Homology modeling indicated that PsRNR had reduced hydrogen bonds and salt bridges, which might be the main reason for the catalytic efficiency at low temperatures. A site directed mutation exhibited that His 667 in the active site was absolutely crucial for the enzyme catalysis. The recombinant PsRNR (rPsRNR) showed maximum activity at 30 °C and had thermal instability, suggesting that rPsRNR was a cold-adapted enzyme. Interestingly, rPsRNR displayed remarkable salt tolerance, remaining stable at 0.5-3.0 M NaCl. Furthermore, rPsRNR had a higher value, contributing to its efficient catalytic activity at a low temperature. Overall, cold-adapted RNase R in this study was an excellent candidate for antimicrobial treatment.
从南极细菌 sp.ANT206 中克隆了一种新型 RNase R，并在 （）中表达。对 基因的生物信息学分析表明，它包含一个 2313bp 的开放阅读框，编码一个 770 个氨基酸的蛋白质（PsRNR）。同源建模表明，PsRNR 具有减少的氢键和盐桥，这可能是其在低温下催化效率的主要原因。定点突变表明，活性位点中的 His 667 对酶催化是绝对关键的。重组 PsRNR（rPsRNR）在 30°C 时表现出最大活性，并且热不稳定性，表明 rPsRNR 是一种耐冷酶。有趣的是，rPsRNR 表现出显著的耐盐性，在 0.5-3.0 M NaCl 下保持稳定。此外，rPsRNR 具有更高的 值，有助于其在低温下的高效催化活性。总的来说，本研究中的耐冷 RNase R 是一种用于抗菌治疗的优秀候选物。
