GLORIA

GEOMAR Library Ocean Research Information Access

X

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Online Resource
    Online Resource
    Circadian clock-controlled gene expression in co-cultured, mat-forming cyanobacteria
    Springer Science and Business Media LLC ; 2020
    In:  Scientific Reports Vol. 10, No. 1 ( 2020-08-24)
    Details
    In: Scientific Reports, Springer Science and Business Media LLC, Vol. 10, No. 1 ( 2020-08-24)
    Abstract: Natural coastal microbial mat communities are multi-species assemblages that experience fluctuating environmental conditions and are shaped by resource competition as well as by cooperation. Laboratory studies rarely address the natural complexity of microbial communities but are usually limited to homogeneous mono-cultures of key species grown in liquid media. The mat-forming filamentous cyanobacteria Lyngbya aestuarii and Coleofasciculus chthonoplastes were cultured under different conditions to investigate the expression of circadian clock genes and genes that are under their control. The cyanobacteria were grown in liquid medium or on a solid substrate (glass beads) as mono- or as co-cultures under a light–dark regime and subsequently transferred to continuous light. TaqMan-probe based qPCR assays were used to quantify the expression of the circadian clock genes kaiA , kaiB, and kaiC , and of four genes that are under control of the circadian clock: psbA , nifH, ftsZ , and prx . Expression of kaiABC was influenced by co-culturing the cyanobacteria and whether grown in liquid media or on a solid substrate. Free-running (i.e. under continuous light) expression cycle of the circadian clock genes was observed in L. aestuarii but not in C. chthonoplastes . In the former organism, maximum expression of psbA and nifH occurred temporally separated and independent of the light regime, although the peak shifted in time when the culture was transferred to continuous illumination. Although functionally similar, both species of cyanobacteria displayed different 24-h transcriptional patterns in response to the experimental treatments, suggesting that their circadian clocks have adapted to different life strategies adopted by these mat-forming cyanobacteria.
    Type of Medium: Online Resource
    ISSN: 2045-2322
    URL: Article
    DOI: 10.1038/s41598-020-69294-3
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2020
    detail.hit.zdb_id: 2615211-3
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 2
    Online Resource
    Online Resource
    Effect of salinity on nitrogenase activity and composition of the active diazotrophic community in intertidal microbial mats
    Springer Science and Business Media LLC ; 2012
    In:  Archives of Microbiology Vol. 194, No. 6 ( 2012-6), p. 483-491
    Details
    In: Archives of Microbiology, Springer Science and Business Media LLC, Vol. 194, No. 6 ( 2012-6), p. 483-491
    Type of Medium: Online Resource
    ISSN: 0302-8933 , 1432-072X
    URL: Article
    DOI: 10.1007/s00203-011-0787-5
    RVK:
    WA 15000
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2012
    detail.hit.zdb_id: 1458451-7
    detail.hit.zdb_id: 124824-8
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 3
    Online Resource
    Online Resource
    Horizontal transfer of the nitrogen fixation gene cluster in the cyanobacterium Microcoleus chthonoplastes
    Oxford University Press (OUP) ; 2010
    In:  The ISME Journal Vol. 4, No. 1 ( 2010-01-01), p. 121-130
    Details
    In: The ISME Journal, Oxford University Press (OUP), Vol. 4, No. 1 ( 2010-01-01), p. 121-130
    Abstract: The filamentous, non-heterocystous cyanobacterium Microcoleus chthonoplastes is a cosmopolitan organism, known to build microbial mats in a variety of different environments. Although most of these cyanobacterial mats are known for their capacity to fix dinitrogen, M. chthonoplastes has not been assigned as a diazotrophic organism. None of the strains that were correctly identified as M. chthonoplastes has been shown to fix dinitrogen and it has repeatedly been reported that these organisms lacked the cyanobacterial nifH, the structural gene for dinitrogenase reductase. In this study, we show that a complete nif-gene cluster is present in the genome of M. chthonoplastes PCC 7420 and that the three structural nitrogenase genes, nifHDK, are present in a collection of axenic strains of M. chthonoplastes from distant locations. Phylogenetic analysis of nifHDK revealed that they cluster with the Deltaproteobacteria and that they are closely related to Desulfovibrio. The nif operon is flanked by typical cyanobacterial genes, suggesting that it is an integral part of the M. chthonoplastes genome. In this study, we provide evidence that the nif operon of M. chthonoplastes is acquired through horizontal gene transfer. Moreover, the presence of the same nif-cluster in M. chthonoplastes isolates derived from various sites around the world suggests that this horizontal gene transfer event must have occurred early in the evolution of M. chthonoplastes. We have been unable to express nitrogenase in cultures of M. chthonoplastes, but we show that these genes were expressed under natural conditions in the field.
    Type of Medium: Online Resource
    ISSN: 1751-7362 , 1751-7370
    URL: Article
    DOI: 10.1038/ismej.2009.99
    Language: English
    Publisher: Oxford University Press (OUP)
    Publication Date: 2010
    detail.hit.zdb_id: 2299378-2
    detail.hit.zdb_id: 2406536-5
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 4
    Online Resource
    Online Resource
    Competition and facilitation between the marine nitrogen-fixing cyanobacterium Cyanothece and its associated bacterial community
    Frontiers Media SA ; 2015
    In:  Frontiers in Microbiology Vol. 5 ( 2015-01-14)
    Details
    In: Frontiers in Microbiology, Frontiers Media SA, Vol. 5 ( 2015-01-14)
    Type of Medium: Online Resource
    ISSN: 1664-302X
    URL: Article
    DOI: 10.3389/fmicb.2014.00795
    Language: Unknown
    Publisher: Frontiers Media SA
    Publication Date: 2015
    detail.hit.zdb_id: 2587354-4
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 5
    Online Resource
    Online Resource
    Microbial carbon metabolism associated with electrogenic sulphur oxidation in coastal sediments
    Oxford University Press (OUP) ; 2015
    In:  The ISME Journal Vol. 9, No. 9 ( 2015-09-01), p. 1966-1978
    Details
    In: The ISME Journal, Oxford University Press (OUP), Vol. 9, No. 9 ( 2015-09-01), p. 1966-1978
    Abstract: Recently, a novel electrogenic type of sulphur oxidation was documented in marine sediments, whereby filamentous cable bacteria (Desulfobulbaceae) are mediating electron transport over cm-scale distances. These cable bacteria are capable of developing an extensive network within days, implying a highly efficient carbon acquisition strategy. Presently, the carbon metabolism of cable bacteria is unknown, and hence we adopted a multidisciplinary approach to study the carbon substrate utilization of both cable bacteria and associated microbial community in sediment incubations. Fluorescence in situ hybridization showed rapid downward growth of cable bacteria, concomitant with high rates of electrogenic sulphur oxidation, as quantified by microelectrode profiling. We studied heterotrophy and autotrophy by following 13C-propionate and -bicarbonate incorporation into bacterial fatty acids. This biomarker analysis showed that propionate uptake was limited to fatty acid signatures typical for the genus Desulfobulbus. The nanoscale secondary ion mass spectrometry analysis confirmed heterotrophic rather than autotrophic growth of cable bacteria. Still, high bicarbonate uptake was observed in concert with the development of cable bacteria. Clone libraries of 16S complementary DNA showed numerous sequences associated to chemoautotrophic sulphur-oxidizing Epsilon- and Gammaproteobacteria, whereas 13C-bicarbonate biomarker labelling suggested that these sulphur-oxidizing bacteria were active far below the oxygen penetration. A targeted manipulation experiment demonstrated that chemoautotrophic carbon fixation was tightly linked to the heterotrophic activity of the cable bacteria down to cm depth. Overall, the results suggest that electrogenic sulphur oxidation is performed by a microbial consortium, consisting of chemoorganotrophic cable bacteria and chemolithoautotrophic Epsilon- and Gammaproteobacteria. The metabolic linkage between these two groups is presently unknown and needs further study.
    Type of Medium: Online Resource
    ISSN: 1751-7362 , 1751-7370
    URL: Article
    DOI: 10.1038/ismej.2015.10
    Language: English
    Publisher: Oxford University Press (OUP)
    Publication Date: 2015
    detail.hit.zdb_id: 2299378-2
    detail.hit.zdb_id: 2406536-5
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 6
    Online Resource
    Online Resource
    Daily rhythmicity in coastal microbial mats
    Springer Science and Business Media LLC ; 2018
    In:  npj Biofilms and Microbiomes Vol. 4, No. 1 ( 2018-05-15)
    Details
    In: npj Biofilms and Microbiomes, Springer Science and Business Media LLC, Vol. 4, No. 1 ( 2018-05-15)
    Abstract: Cyanobacteria are major primary producers in coastal microbial mats and provide biochemical energy, organic carbon, and bound nitrogen to the mat community through oxygenic photosynthesis and dinitrogen fixation. In order to anticipate the specific requirements to optimize their metabolism and growth during a day-and-night cycle, Cyanobacteria possess a unique molecular timing mechanism known as the circadian clock that is well-studied under laboratory conditions but little is known about its function in a natural complex community. Here, we investigated daily rhythmicity of gene expression in a coastal microbial mat community sampled at 6 time points during a 24-h period. In order to identify diel expressed genes, meta-transcriptome data was fitted to periodic functions. Out of 24,035 conserved gene transcript clusters, approximately 7% revealed a significant rhythmic expression pattern. These rhythmic genes were assigned to phototrophic micro-eukaryotes, Cyanobacteria but also to Proteobacteria and Bacteroidetes. Analysis of MG-RAST annotated genes and mRNA recruitment analysis of two cyanobacterial and three proteobacterial microbial mat members confirmed that homologs of the cyanobacterial circadian clock genes were also found in other bacterial members of the microbial mat community. These results suggest that various microbial mat members other than Cyanobacteria have their own molecular clock, which can be entrained by a cocktail of Zeitgebers such as light, temperature or metabolites from neighboring species. Hence, microbial mats can be compared to a complex organism consisting of multiple sub-systems that have to be entrained in a cooperative way such that the corpus functions optimally.
    Type of Medium: Online Resource
    ISSN: 2055-5008
    URL: Article
    DOI: 10.1038/s41522-018-0054-5
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2018
    detail.hit.zdb_id: 2817021-0
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...