TY  - JOUR
N1  - Copyright of this article belongs to ELSEVIER
ID  - open2734
UR  - https://www.sciencedirect.com/science/article/abs/pii/S0141813021016901?via%3Dihub
A1  - Vasudeva, Gunjan
A1  - Sidhu, Chandni
A1  - Kalidas, Nidhi
A1  - Ganguly, Ashish
A1  - Pinnaka, Anil Kumar
Y1  - 2021/10/01/
N2  - The oxygenases have attracted considerable attention in enzyme-mediated bioremediation of xenobiotic compounds due to their high specificity, cost-effectiveness, and targeted field applications. Here, we performed a functional metagenomics approach to cope with culturability limitations to isolate a novel extradiol dioxygenase. Fosmid clone harboring dioxygenase gene was sequenced and analyzed by bioinformatics tools. One ring-cleaving dioxygenase RW4-MPC (metapyrocatechase) was purified and characterized to examine its degradation efficiency. The RW4-MPC was significantly active in the temperature and pH range of 5 to 40 °C, and 7-10, respectively, with an optimum temperature of 25 °C and pH 8. To gain insight into observed differential activity, Small-Angle X-ray Scattering (SAXS) data of the protein samples were analyzed, which brought forth that the RW4-MPC molecules form tight globular tetramers in solution. This native association was stable till 35 °C, and protein started to associate at higher temperatures, explaining heat-induced loss of function. Similarly, RW4-MPC aggregated or lost globular profile below pH 7 or at pH 10, respectively. The kinetic parameters showed the six folds high catalytic efficiency of RW4-MPC towards 2,3-dihydroxy biphenyl than catechol and its derivatives. RW4-MPC molecules showed remarkable retention of functionality in hypersaline conditions with more than 70% activity in a buffer having 3 M NaCl concentration. In concordance, SAXS data analysis showed retention of functional shape profile in hypersaline conditions. The halotolerant and oxygen insensitive nature of this enzyme makes it a potential candidate for bioremediation.
PB  - Elsevier
JF  - INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
VL  - 188
KW  - Meta-cleavage dioxygenase; Metagenomics; SAXS; Tetramer; 
TI  - Shape-function of a novel metapyrocatechase, RW4-MPC: Metagenomics to SAXS data based insight into deciphering regulators of function
SP  - 1012
EP  - 1024
ER  -