Computer Aided Rational Design Provides a New Tool to Improve Protein Thermostability
The ability to design thermostable proteins offers enormous potential for the development of novel protein bioreagents. In a recent work by Dr. YAO Lishan and his colleagues at Qingdao Institute of Bioenergy and Bioprocess Technology (QIBEBT), a combined computational and experimental method was developed to increase the Tm of the flavin mononucleotide based fluorescent protein Bacillus Subtilis YtvA LOV domain by 31 Celsius, thus extending its applicability in thermophilic systems (Figure 1).
Figure 1. Thermal denaturation of the WT FbFP, the single point mutant N124Y, and the triple mutant N107Y-N124Y-M111F. The fluorescence intensity of the bound FMN is used to monitor the protein denaturation. As can be seen, the mutants have higher percentages of fluorescence at elevated temperature than WT suggesting mutations increase FbFP thermostability.
The method includes five steps, the single mutant computer screening to identify thermostable mutant candidates, the experimental evaluation to confirm the positive selections, the computational redesign around the thermostable mutation regions, the experimental reevaluation and finally the multiple mutations combination. The adopted method is simple and effective, can be applied to other important proteins where traditional methods have difficulties, and therefore provides a new tool to improve protein thermostability.
This work has been published online in plos computational biology, with the link http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1003129 (download for free).
Contact:
Prof. YAO Lishan
Email: yaols (AT) qibebt.ac.cn
