Click here to view fulltext PDF

Permanent link:
https://www.ias.ac.in/article/fulltext/jbsc/045/0054

Bioinformatics design; flexibility; loop deletion; organophosphorus compounds; organophosphorus hydrolase; thermostability improvement

Thermostability improvement of enzymes used industrially or commercially would develop their capacity andcommercial potential due to increased enzymatic competence and cost-effectiveness. Several stabilizing factorshave been suggested to be the base of thermal stability, like proline replacements, disulfide bonds, surface looptruncation and ionic pair networks creation. This research evaluated the mechanism of increasing the rigidity oforganophosphorus hydrolase enzyme by flexible loop truncation. Bioinformatics analysis revealed that themutated protein retains its stability after loop truncation (five amino acids deleted). The thermostability of thewild-type (OPH-wt) and mutated (OPH-D5) enzymes were investigated by half-life, DGi, and fluorescence andfar-UV CD analysis. Results demonstrated an increase half-life and DGi in OPH-D5 compared to OPH-wt.These results were confirmed by extrinsic fluorescence and circular dichroism (CD) spectrometry experiments,therefore, as rigidity increased in OPHD5 after loop truncation, half-life and DGi also increased. Based onthese findings, a strong case is presented for thermostability improvement of OPH enzyme by flexible looptruncation after bioinformatics analysis.

GHOLAMREZA FARNOOSH¹ KHOSRO KHAJEH² MOZAFAR MOHAMMADI¹ KAZEM HASSANPOUR³ ALI MOHAMMAD LATIFI¹ HOSSEIN AGHAMOLLAEI⁴

1. Applied Biotechnology Research Centre, Baqiyatallah University of Medical Sciences, Tehran, Iran
2. Department of Biochemistry, Faculty of Biologic Science, Tarbiat Modares University, Tehran, Iran
3. Medical School, Sabzevar University of Medical Sciences, Sabzevar, Iran
4. Chemical Injuries Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran

Published

31 March 2020