Multiple resistance mechanisms in Staphylococcus sp. strain AS6 under arsenite stress and its potential use in amelioration of wastewater

• Main Authors: Shahid Sher, Syed Zajif Hussain, Abdul Rehman
• Format: Article
• Language: English
• Published: Elsevier 2020-10-01
• Series: Journal of King Saud University: Science
• Subjects: Arsenite; Heavy metals; Staphylococcus sp. strain AS6; Glutathione; Antioxidant enzymes; Bioremediation
• Online Access: http://www.sciencedirect.com/science/article/pii/S1018364720302512

The multiple metal resistant Staphylococcus sp. strain AS6, isolated from wastewater of Pakistan, was able to resist 25 mM arsenite and 150 mM arsenate. SEM analysis showed that no significant change in bacterial morphology under arsenite exposure was observed while EDX and FTIR analyses confirmed the surface adsorption and uptake of arsenite into the bacterial cells exposed to 15 mM arsenite. The GSH/GSSG ratio and NPSHs were increased 45.0 and 76.50% in 15 mM arsenite stress while antioxidant enzymes (SOD, CAT, POX, and APX) showed varied response in arsenic presence. The genome of strain AS6 was sequenced through Illumina NextSeq 550 sequencer and the genes confer resistance to arsenic such as arsR, arsB, and arsC were identified. The bacterial stain AS6 was able to oxidize arsenite 91%/8h and removed 93%/10 h arsenite through its inactivated biomass from the medium. The strain AS6 has great potential, due to its hyper-metal resistance and high arsenite oxidation ability, to be used as a bioresource for green chemistry to eliminate toxic arsenite from the environment.