• Login
    View Item 
    •   DSpace Home
    • Institute's contributions
    • Scholarly literature
    • View Item
    •   DSpace Home
    • Institute's contributions
    • Scholarly literature
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Degradation of alkenones by aerobic heterotrophic bacteria: Selective or not ?

    Thumbnail
    View/Open
    Org_Geochem_39_34.pdf (447.1Kb)
    Author version OA (537.9Kb)
    Date
    2008
    Author
    Rontani, J-F.
    Harji, R.
    Guasco, S.
    Prahl, F.G.
    Volkman, J.K.
    Bhosle, N.B.
    Bonin, P.
    Metadata
    Show full item record
    Abstract
    Four bacterial communities were isolated from Emiliania huxleyi strain TWP1 cultures before and after the algal cells had been treated with different antibiotics. Incubation of E. huxleyi with these bacterial communities resulted in dramatically different extents of alkenone degradation, ranging from effectively none to extensive. Selective degradation of the more unsaturated alkenones was observed in experiments using the total bacterial community and one of the communities isolated from antibiotic-treated algal cells. The observed increases in U sup (k’) sub(37) are equivalent to a +2 degrees C and +3.3 degrees C change in the inferred temperature. Our results clearly show that intense aerobic microbial degradative processes have the potential to introduce a significant ‘warm’ bias in palaeotemperature reconstruction and could explain apparent anomalies in palaeotemperatures inferred from alkenone distributions in strongly oxidizing sedimentary environments. The results show that aerobic bacteria capable of selectively degrading alkenones are not limited to particular environments such as microbial mats and can be actually associated with living E. huxleyi cells. The detection of epoxyketones in some cultures indicates that metabolic pathways involving attack at the terminal groups of the molecule are essentially non-selective, while those acting on alkenone double bonds are selective. The epoxyketones resulting from bacterial epoxidation of alkenone double bonds could be useful indicators of aerobic bacterial alteration of the alkenone unsaturation ratio in situ. The production of alkenols during incubation with one of the bacterial communities demonstrated for the first time that bacterial reduction of alkenones can be a potential source of these compounds in the environment. The intriguing production of small amounts of monounsaturated alkenones by one of the bacterial communities also raises the possibility of a bacterial reduction of alkenone double bonds.
    URI
    http://drs.nio.org/drs/handle/2264/1034
    Collections
    • Scholarly literature [9141]

    DSpace software copyright © 2002-2016  DuraSpace
    Contact Us | Send Feedback
    Theme by 
    Atmire NV
     

     

    Browse

    All of DSpaceCommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsThis CollectionBy Issue DateAuthorsTitlesSubjects

    My Account

    LoginRegister

    DSpace software copyright © 2002-2016  DuraSpace
    Contact Us | Send Feedback
    Theme by 
    Atmire NV