Regulation of proteorhodopsin gene expression by nutrient limitation in the marine bacterium Vibrio sp. AND4
Summary Proteorhodopsin (PR), a ubiquitous membrane photoprotein in marine environments, acts as a light‐driven proton pump and can provide energy for bacterial cellular metabolism. However, knowledge of factors that regulate PR gene expression in different bacteria remains strongly limited. Here, e...
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Published in | Environmental microbiology Vol. 15; no. 5; pp. 1400 - 1415 |
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Main Authors | , , , , , , , |
Format | Journal Article |
Language | English |
Published |
England
Blackwell Publishing Ltd
01.05.2013
Wiley Subscription Services, Inc |
Subjects | |
Online Access | Get full text |
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Summary: | Summary
Proteorhodopsin (PR), a ubiquitous membrane photoprotein in marine environments, acts as a light‐driven proton pump and can provide energy for bacterial cellular metabolism. However, knowledge of factors that regulate PR gene expression in different bacteria remains strongly limited. Here, experiments with Vibrio sp. AND4 showed that PR phototrophy promoted survival only in cells from stationary phase and not in actively growing cells. PR gene expression was tightly regulated, with very low values in exponential phase, a pronounced peak at the exponential/stationary phase intersection, and a marked decline in stationary phase. Thus, PR gene expression at the entry into stationary phase preceded, and could therefore largely explain, the stationary phase light‐induced survival response in AND4. Further experiments revealed nutrient limitation, not light exposure, regulated this differential PR expression. Screening of available marine vibrios showed that the PR gene, and thus the potential for PR phototrophy, is found in at least three different clusters in the genus Vibrio. In an ecological context, our findings suggest that some PR‐containing bacteria adapted to the exploitation of nutrient‐rich micro‐environments rely on a phase of relatively slowly declining resources to mount a cellular response preparing them for adverse conditions dispersed in the water column. |
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Bibliography: | istex:2229293062BC124E63A4F7A77E299CD26D9C6AE7 ark:/67375/WNG-TG6S6WQ5-C Linnaeus University MarineGems - No. CTM2010-20361 Fig. S1. Genetic organization of the prd loci in various Vibrio species. The genes shared between strains are colour coded. PRs and the associated genes for retinal synthesis (shared in all) are shown in red. Transposases are in blue. Genes shared among Vibrio sp. AND4, V. campbellii DS40M4 and V. campbellii BAA-1116 are in yellow while the genes shared only between the latter two are in green. The region to the left of the PR gene in PEL22A is not drawn because of the low sequence quality in this region. Note the location of the idi gene in V. splendidus - further detail regarding this gene in vibrios is provided in Fig. . ArticleID:EMI12085 Spanish Ministry of Science and Innovation - No. CSD2008-00077 Swedish Research Councils VR and FORMAS ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 1462-2912 1462-2920 1462-2920 |
DOI: | 10.1111/1462-2920.12085 |