TY - JOUR

T1 - Engineered nickel bioaccumulation in Escherichia coli by NikABCDE transporter and metallothionein overexpression

AU - Diep, Patrick

AU - Leo Shen, Heping

AU - Wiesner, Julian A

AU - Mykytczuk, Nadia

AU - Papangelakis, Vladimiros

AU - Yakunin, Alexander F

AU - Mahadevan, Radhakrishnan

N1 - © 2023 The Authors. Engineering in Life Sciences published by Wiley‐VCH GmbH.

PY - 2023/7

Y1 - 2023/7

N2 - Mine wastewater often contains dissolved metals at concentrations too low to be economically extracted by existing technologies, yet too high for environmental discharge. The most common treatment is chemical precipitation of the dissolved metals using limestone and subsequent disposal of the sludge in tailing impoundments. While it is a cost-effective solution to meet regulatory standards, it represents a lost opportunity. In this study, we engineered Escherichia coli to overexpress its native NikABCDE transporter and a heterologous metallothionein to capture nickel at concentrations in local effluent streams. We found the engineered strain had a 7-fold improvement in the bioaccumulation performance for nickel compared to controls, but also observed a drastic decrease in cell viability due to metabolic burden or inducer (IPTG) toxicity. Growth kinetic analysis revealed the IPTG concentrations used based on past studies lead to growth inhibition, thus delineating future avenues for optimization of the engineered strain and its growth conditions to perform in more complex environments.

AB - Mine wastewater often contains dissolved metals at concentrations too low to be economically extracted by existing technologies, yet too high for environmental discharge. The most common treatment is chemical precipitation of the dissolved metals using limestone and subsequent disposal of the sludge in tailing impoundments. While it is a cost-effective solution to meet regulatory standards, it represents a lost opportunity. In this study, we engineered Escherichia coli to overexpress its native NikABCDE transporter and a heterologous metallothionein to capture nickel at concentrations in local effluent streams. We found the engineered strain had a 7-fold improvement in the bioaccumulation performance for nickel compared to controls, but also observed a drastic decrease in cell viability due to metabolic burden or inducer (IPTG) toxicity. Growth kinetic analysis revealed the IPTG concentrations used based on past studies lead to growth inhibition, thus delineating future avenues for optimization of the engineered strain and its growth conditions to perform in more complex environments.

U2 - 10.1002/elsc.202200133

DO - 10.1002/elsc.202200133

M3 - Article

C2 - 37408871

VL - 23

JO - Engineering in life sciences

JF - Engineering in life sciences

SN - 1618-0240

IS - 7

M1 - 2200133

ER -