Metal resistance in acidophilic microorganisms and its significance for biotechnologies

Dopson, M; Holmes, DS

Abstract

Extremely acidophilic microorganisms have an optimal pH of < 3 and are found in all three domains of life. As metals are more soluble at acid pH, acidophiles are often challenged by very high metal concentrations. Acidophiles are metal-tolerant by both intrinsic, passive mechanisms as well as active systems. Passive mechanisms include an internal positive membrane potential that creates a chemiosmotic gradient against which metal cations must move, as well as the formation of metal sulfate complexes reducing the concentration of the free metal ion. Active systems include efflux proteins that pump metals out of the cytoplasm and conversion of the metal to a less toxic form. Acidophiles are exploited in a number of biotechnologies including biomining for sulfide mineral dissolution, biosulfidogenesis to produce sulfide that can selectively precipitate metals from process streams, treatment of acid mine drainage, and bioremediation of acidic metal-contaminated milieux. This review describes how acidophilic microorganisms tolerate extremely high metal concentrations in biotechnological processes and identifies areas of future work that hold promise for improving the efficiency of these applications.

Más información

Título según WOS: Metal resistance in acidophilic microorganisms and its significance for biotechnologies
Título según SCOPUS: Metal resistance in acidophilic microorganisms and its significance for biotechnologies
Título de la Revista: APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
Volumen: 98
Número: 19
Editorial: Springer
Fecha de publicación: 2014
Página de inicio: 8133
Página final: 8144
Idioma: English
DOI:

10.1007/s00253-014-5982-2

Notas: ISI, SCOPUS