Light stimulates growth of proteorhodopsin-containing marine Flavobacteria
Artikel i vetenskaplig tidskrift, 2007

Proteorhodopsins are bacterial light-dependent proton pumps. Their discovery within genomic material from uncultivated marine bacterioplankton caused considerable excitement because it indicated a potential phototrophic function within these organisms, which had previously been considered strictly chemotrophic. Subsequent studies established that sequences encoding proteorhodopsin are broadly distributed throughout the world's oceans. Nevertheless, the role of proteorhodopsins in native marine bacteria is still unknown. Here we show, from an analysis of the complete genomes of three marine Flavobacteria, that cultivated bacteria in the phylum Bacteroidetes, one of the principal components of marine bacterioplankton, contain proteorhodopsin. Moreover, growth experiments in both natural and artificial seawater (low in labile organic matter, which is typical of the world's oceans) establish that exposure to light results in a marked increase in the cell yield of one such bacterium (Dokdonia sp. strain MED134) when compared with cells grown in darkness. Thus, our results show that the phototrophy conferred by proteorhodopsin can provide critical amounts of energy, not only for respiration and maintenance but also for active growth of marine bacterioplankton in their natural environment. ©2007 Nature Publishing Group.

Författare

Laura Gomez-Consarna

Hogskolan i Kalmar

,Jose M. Gonzalez

Universidad de la Laguna

Montserrat Coll-Llado

CSIC - Centro Mediterraneo de Investigaciones Marinas y Ambientales (CMIMA)

Pontus Emanuel Gourdon

Chalmers, Kemi- och bioteknik, Molekylär bioteknik

Torbjoern Pascher

Lunds universitet

Richard Neutze

Göteborgs universitet

Carlos Pedros-Alio

CSIC - Centro Mediterraneo de Investigaciones Marinas y Ambientales (CMIMA)

Jarone Pinhassi

Hogskolan i Kalmar

Nature

0028-0836 (ISSN) 1476-4687 (eISSN)

Vol. 445 210-213

Ämneskategorier

Biokemi och molekylärbiologi

DOI

10.1038/nature05381