Scheda di dettaglio – i prodotti della ricerca
| Dato | Valore |
|---|---|
| Title | Grazing resistant freshwater bacteria profit from chitin and cell-wall-derived organic carbon |
| Abstract | The rise of grazing resistant planktonic bacteria in freshwater lakes during vernal phytoplankton blooms is favoured by predation of heterotrophic nanoflagellates (HNF). The spring period is also characterized by increased availability of organic carbon species that are in parts derived from cellular debris generated during bacterivory or viral lysis, such as peptidoglycan, chitin and their subunit N-acetylglucosamine (NAG). We tested the hypothesis that two dominant grazing resistant bacterial taxa, the ac1 tribe of Actinobacteria (ac1) and filamentous bacteria from the LD2 lineage (Saprospiraceae), profit from such carbon sources during periods of intense HNF predation. The abundances of ac1 and LD2 rose in parallel with HNF, and disproportionally high fractions of cells from both lineages were involved in NAG uptake. Members of ac1 and LD2 were significantly more enriched after NAG addition to lake water. However, highest growth rates of both bacterial lineages were found on chitin and peptidoglycan. Moreover, the direct or indirect transfer of organic carbon from peptidoglycan to LD2 filaments could be demonstrated. We thus provide evidence that these taxa may benefit twofold from protistan predation: by removal of their competitors, and by specific physiological adaptations to utilize carbon sources that are released during grazing or viral lysis. |
| Source | Environmental microbiology (Print) 15 (7), pp. 2019–2030 |
| Keywords | Freshwater bacteriaOrganic carbon |
| Journal | Environmental microbiology (Print) |
| Editor | Blackwell Science., Oxford, Regno Unito |
| Year | 2013 |
| Type | Articolo in rivista |
| DOI | 10.1111/1462-2920.12083 |
| Authors | Ester Maria Eckert; Michael Baumgartner; Iris M. Huber; Jakob Pernthaler |
| Text | 313379 2013 10.1111/1462 2920.12083 ISI Web of Science WOS 000328955900009 Freshwater bacteria Organic carbon Grazing resistant freshwater bacteria profit from chitin and cell wall derived organic carbon Ester Maria Eckert; Michael Baumgartner; Iris M. Huber; Jakob Pernthaler Ester Maria Eckert CNR ISE, Pallanza Verbania; Michael Baumgartner, Iris M. Huber, Jakob Pernthaler Limnological Station, Institute of Plant Biology, University of Zurich CH The rise of grazing resistant planktonic bacteria in freshwater lakes during vernal phytoplankton blooms is favoured by predation of heterotrophic nanoflagellates HNF . The spring period is also characterized by increased availability of organic carbon species that are in parts derived from cellular debris generated during bacterivory or viral lysis, such as peptidoglycan, chitin and their subunit N acetylglucosamine NAG . We tested the hypothesis that two dominant grazing resistant bacterial taxa, the ac1 tribe of Actinobacteria ac1 and filamentous bacteria from the LD2 lineage Saprospiraceae , profit from such carbon sources during periods of intense HNF predation. The abundances of ac1 and LD2 rose in parallel with HNF, and disproportionally high fractions of cells from both lineages were involved in NAG uptake. Members of ac1 and LD2 were significantly more enriched after NAG addition to lake water. However, highest growth rates of both bacterial lineages were found on chitin and peptidoglycan. Moreover, the direct or indirect transfer of organic carbon from peptidoglycan to LD2 filaments could be demonstrated. We thus provide evidence that these taxa may benefit twofold from protistan predation by removal of their competitors, and by specific physiological adaptations to utilize carbon sources that are released during grazing or viral lysis. 15 Published version ID_PUMA cnr.ise/2013 A0 061 Grazing resistant freshwater bacteria profit from chitin and cell wall derived organic carbon 2013_A0_061.pdf Articolo in rivista Blackwell Science. 1462 2912 Environmental microbiology Print Environmental microbiology Print Environ. microbiol. Print estermaria.eckert ECKERT ESTER MARIA TA.P04.016.004 Ecologia teorica e applicata degli ecosistemi acquatici |