Sulfate-reducing bacteria in floating macrophyte rhizospheres from an Amazonian floodplain lake in Bolivia and their association with Hg methylation

Darío Achá, Volga Iñiguez, Marc Roulet, Jean Remy Davée Guimarães, Ruddy Luna, Lucia Alanoca, Samanta Sanchez

Research output: Contribution to journalArticlepeer-review

70 Scopus citations

Abstract

Five subgroups of sulfate-reducing bacteria (SRB) were detected by PCR in three macrophyte rhizospheres (Polygonum densiflorum, Hymenachne donacifolia, and Ludwigia helminthorriza) and three subgroups in Eichhornia crassipes from La Granja, a floodplain lake from the upper Madeira basin. The SRB community varied according to the macrophyte species but with different degrees of association with their roots. The rhizosphere of the C4 plant Polygonum densiflorum had higher frequencies of SRB subgroups as well as higher mercury methylation potentials (27.5 to 36.1%) and carbon (16.06 ± 5.40%), nitrogen (2.03 ± 0.64%), Hg (94.50 ± 6.86 ng Hg g -1), and methylmercury (8.25 ± 1.45 ng Hg g-1) contents than the rhizosphere of the C3 plant Eichhornia crassipes. Mercury methylation in Polygonum densiflorum and Eichhornia crassipes was reduced when SRB metabolism was inhibited by sodium molybdate.

Original languageEnglish
Pages (from-to)7531-7535
Number of pages5
JournalApplied and Environmental Microbiology
Volume71
Issue number11
DOIs
StatePublished - Nov 2005

Fingerprint

Dive into the research topics of 'Sulfate-reducing bacteria in floating macrophyte rhizospheres from an Amazonian floodplain lake in Bolivia and their association with Hg methylation'. Together they form a unique fingerprint.

Cite this