Reversible oxygen‐tolerant hydrogenase carried by free‐living N 2 ‐fixing bacteria isolated from the rhizospheres of rice, maize, and wheat - CNRS - Centre national de la recherche scientifique Accéder directement au contenu
Article Dans Une Revue MicrobiologyOpen Année : 2012

Reversible oxygen‐tolerant hydrogenase carried by free‐living N 2 ‐fixing bacteria isolated from the rhizospheres of rice, maize, and wheat

Résumé

Hydrogen production by microorganisms is often described as a promising sustainable and clean energy source, but still faces several obstacles, which prevent practical application. Among them, oxygen sensitivity of hydrogenases represents one of the major limitations hampering the biotechnological implementation of photobiological production processes. Here, we describe a hierarchical biodiversity-based approach, including a chemochromic screening of hydrogenase activity of hundreds of bacterial strains collected from several ecosystems, followed by mass spectrometry measurements of hydrogenase activity of a selection of the H2-oxidizing bacterial strains identified during the screen. In all, 131 of 1266 strains, isolated from cereal rhizospheres and basins containing irradiating waste, were scored as H2-oxidizing bacteria, including Pseudomonas sp., Serratia sp., Stenotrophomonas sp., Enterobacter sp., Rahnella sp., Burkholderia sp., and Ralstonia sp. isolates. Four free-living N2-fixing bacteria harbored a high and oxygen-tolerant hydrogenase activity, which was not fully inhibited within entire cells up to 150–250 μmol/L O2 concentration or within soluble protein extracts up to 25–30 μmol/L. The only hydrogenase-related genes that we could reveal in these strains were of the hyc type (subunits of formate hydrogenlyase complex). The four free-living N2-fixing bacteria were closely related to Enterobacter radicincitans based on the sequences of four genes (16S rRNA, rpoB, hsp60, and hycE genes). These results should bring interesting prospects for microbial biohydrogen production and might have ecophysiological significance for bacterial adaptation to the oxic–anoxic interfaces in the rhizosphere.
Fichier principal
Vignette du fichier
mbo30001-0349.pdf (2.01 Mo) Télécharger le fichier
Origine : Fichiers éditeurs autorisés sur une archive ouverte

Dates et versions

hal-03430374 , version 1 (19-09-2023)

Identifiants

Citer

Philippe Roumagnac, Pierre Richaud, ​mohamed Barakat, Philippe Ortet, Marie‐anne Roncato, et al.. Reversible oxygen‐tolerant hydrogenase carried by free‐living N 2 ‐fixing bacteria isolated from the rhizospheres of rice, maize, and wheat. MicrobiologyOpen, 2012, 1 (4), pp.349-361. ⟨10.1002/mbo3.37⟩. ⟨hal-03430374⟩
23 Consultations
3 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More