Home About us MoEF Contact us Sitemap Tamil Website  
About Envis
Whats New
Microorganisms
Research on Microbes
Database
Bibliography
Publications
Library
E-Resources
Microbiology Experts
Events
Online Submission
Access Statistics

Site Visitors

blog tracking


 
PNAS
Vol.
109, No. 19, 2012; Pages: 1173 - 1182

Metaproteomics of a gutless marine worm and its symbiotic microbial community reveal unusual pathways for carbon and energy use

Manuel Kleiner, Cecilia Wentrup, Christian Lott, Hanno Teeling, Silke Wetzel, Jacque Young, Yun-Juan Chang, Manesh Shah, Nathan C. VerBerkmoes, Jan Zarzycki, Georg Fuchs, Stephanie Markert, Kristina Hempel, Birgit Voigt, Dörte Becher, Manuel Liebeke, Michael Lalk, Dirk Albrecht, Michael Hecker, Thomas Schweder and Nicole Dubilier

Symbiosis Group, Max Planck Institute for Marine Microbiology, 28359 Bremen, Germany.

Abstract

Low nutrient and energy availability has led to the evolution of numerous strategies for overcoming these limitations, of which symbiotic associations represent a key mechanism. Particularly striking are the associations between chemosynthetic bacteria and marine animals that thrive in nutrient-poor environments such as the deep sea because the symbionts allow their hosts to grow on inorganic energy and carbon sources such as sulfide and CO2. Remarkably little is known about the physiological strategies that enable chemosynthetic symbioses to colonize oligotrophic environments. In this study, we used metaproteomics and metabolomics to investigate the intricate network of metabolic interactions in the chemosynthetic association between Olavius algarvensis, a gutless marine worm, and its bacterial symbionts. We propose previously undescribed pathways for coping with energy and nutrient limitation, some of which may be widespread in both free-living and symbiotic bacteria. These pathways include (i) a pathway for symbiont assimilation of the host waste products acetate, propionate, succinate and malate; (ii) the potential use of carbon monoxide as an energy source, a substrate previously not known to play a role in marine invertebrate symbioses; (iii) the potential use of hydrogen as an energy source; (iv) the strong expression of high-affinity uptake transporters; and (v) as yet undescribed energy-efficient steps in CO2 fixation and sulfate reduction. The high expression of proteins involved in pathways for energy and carbon uptake and conservation in the O. algarvensis symbiosis indicates that the oligotrophic nature of its environment exerted a strong selective pressure in shaping these associations.

Keywords: 3-hydroxypropionate bi-cycle; Calvin cycle; proton-translocating pyrophosphatase; pyrophosphate dependent phosphofructokinase; metagenomics


 

 

 
Copyright © 2005 ENVIS Centre ! All rights reserved
This site is optimized for 1024 x 768 screen resolution