PubAg

Main content area

Evolution of copper arsenate resistance for enhanced enargite bioleaching using the extreme thermoacidophile Metallosphaera sedula

Author:
Ai, Chenbing, McCarthy, Samuel, Liang, Yuting, Rudrappa, Deepak, Qiu, Guanzhou, Blum, Paul
Source:
Journal of industrial microbiology & biotechnology 2017 v.44 no.12 pp. 1613-1625
ISSN:
1367-5435
Subject:
bioleaching, community structure, copper, copper arsenate, cross resistance, genetic engineering, microbial communities, mutation, pulp
Abstract:
Adaptive laboratory evolution (ALE) was employed to isolate arsenate and copper cross-resistant strains, from the copper-resistant M. sedula CuR1. The evolved strains, M. sedula ARS50-1 and M. sedula ARS50-2, contained 12 and 13 additional mutations, respectively, relative to M. sedula CuR1. Bioleaching capacity of a defined consortium (consisting of a naturally occurring strain and a genetically engineered copper sensitive strain) was increased by introduction of M. sedula ARS50-2, with 5.31 and 26.29% more copper recovered from enargite at a pulp density (PD) of 1 and 3% (w/v), respectively. M. sedula ARS50-2 arose as the predominant species and modulated the proportions of the other two strains after it had been introduced. Collectively, the higher Cu²⁺ resistance trait of M. sedula ARS50-2 resulted in a modulated microbial community structure, and consolidating enargite bioleaching especially at elevated PD.
Agid:
5855906