In:
Molecular Microbiology, Wiley, Vol. 100, No. 6 ( 2016-06), p. 945-953
Abstract:
Microbial biotransformations are major contributors to the arsenic biogeocycle. In parallel with transformations of inorganic arsenic, organoarsenicals pathways have recently been recognized as important components of global cycling of arsenic. The well‐characterized pathway of resistance to arsenate is reduction coupled to arsenite efflux. Here, we describe a new pathway of arsenate resistance involving biosynthesis and extrusion of an unusual pentavalent organoarsenical. A number of arsenic resistance ( ars ) operons have two genes of unknown function that are linked in these operons. One, gapdh , encodes the glycolytic enzyme glyceraldehyde‐3‐phosphate dehydrogenase. The other, arsJ , encodes a major facilitator superfamily (MFS) protein. The two genes were cloned from the chromosome of Pseudomonas aeruginosa . When expressed together, but not alone, in Escherichia coli, gapdh and arsJ specifically conferred resistance to arsenate and decreased accumulation of As(V). Everted membrane vesicles from cells expressing arsJ accumulated As(V) in the presence of purified GAPDH, D‐glceraldehylde 3‐phosphate (G3P) and NAD + . GAPDH forms the unstable organoarsenical 1‐arseno‐3‐phosphoglycerate (1As3PGA). We propose that ArsJ is an efflux permease that extrudes 1As3PGA from cells, where it rapidly dissociates into As(V) and 3‐phosphoglycerate (3PGA), creating a novel pathway of arsenate resistance.
Type of Medium:
Online Resource
ISSN:
0950-382X
,
1365-2958
DOI:
10.1111/mmi.2016.100.issue-6
Language:
English
Publisher:
Wiley
Publication Date:
2016
detail.hit.zdb_id:
1501537-3
detail.hit.zdb_id:
619315-8
