NAP enzyme recruitment in simultaneous bioremediation and nanoparticles synthesis

Marwa Eltarahony; Sahar Zaki; Zeinab Kheiralla; Desouky Abd-El-Haleem

doi:10.1016/j.btre.2018.e00257

NAP enzyme recruitment in simultaneous bioremediation and nanoparticles synthesis

Biotechnol Rep (Amst). 2018 May 17:18:e00257. doi: 10.1016/j.btre.2018.e00257. eCollection 2018 Jun.

Authors

Marwa Eltarahony¹, Sahar Zaki¹, Zeinab Kheiralla², Desouky Abd-El-Haleem¹

Affiliations

¹ Environmental Biotechnology Department, Genetic Engineering and Biotechnology Research Institute, City of Scientific Research and Technological Applications, 21934 Borgelarab, Alexandria, Egypt.
² Botany Department, College of Women for Arts, Science and Education, Ain Shams University, Cairo, Egypt.

Abstract

The periplasmic nitrate reductase enzyme (NAP) has become attractive catalyst, whose exploitation has emerged as one of the indispensable strategies toward environmentally benign applications. To achieve them efficiently and overcome the sensitivity of NAP in harsh environmental circumstances, the immobilization for denitrifying bacteria and NAP enzyme for simultaneous bioremediation and bionanoparticles synthesis was studied. NAP catalyzed NO₃^- reduction at V_max of 0.811 μM/min and K_m of 14.02 mM. Concurrently, the immobilized MMT cells completely removed NO₃- upon 192 h with AgNPs synthesis ranging from 23.26 to 58.14 nm as indicated by SEM. Wherase, immobilized NAP exhibited lower efficiency with 28.6% of NO₃^- elimination within 288 h and large aggregated AgNPs ranging from 94.44 nm to 172.22 nm. To the best of author knowledge, the immobilization for denitrifying bacteria and NAP enzyme for simultaneous bioremediation and bionanoparticles synthesis was not studied before.

Keywords: Bioremediation; Denitrification; Immobilization; Nanoparticles; Nitrate reductase.