Catalysis Letters, Vol.148, No.12, 3732-3740, 2018
Magnetic Multienzyme Nanoparticles Catalyzed Degradation of Aqueous Tributyltin
Degradation of aqueous tributyltin (TBT), an organotin compound extensively used in marine machineries but with high toxicity towards broad spectra of organisms, is essential to sustain marine ecosystem. The present study started with isolating a TBT-resistant strain F-2 capable of degrading TBT in M9 minimal medium, as either live cells or homogenates. Strain F-2 was identified by 16S rDNA sequence and phylogenetic tree analysis as closely related to Pseudomonas stutzeri (99%). LC-MS/MS protein identification result of the strain F-2 shown overexpressed proteins including antioxidant enzyme, cold-shock protein and elongation factor Tu after incubation in M9 medium containing TBT. Next, enzyme extract of the strain F-2 was immobilized by cross-linking on concanavalin A-Fe3O4 magnetic nanoparticles (CE@ConA-MNP). Analysis by SEM, TEM, XRD and laser confocal microscopy confirmed the co-localization of enzymes. The immobilized multi-enzyme offered a wide operational spectrum in terms of salinity, pH and temperature and was ease of recover. Finally, the CE@ConA-MNP was tested in artificial seawater (3.6% salinity) containing 1.0mM TBT and removed 55.5% TBT within 1h, indicating its potential for the degradation of aqueous TBT. [GRAPHICS] .