Light and Primary Production Shape Bacterial Activity and Community Composition of Aerobic Anoxygenic Phototrophic Bacteria in a Microcosm Experiment
| Autor: | Hans-Peter Grossart, Izabela Mujakić, Andrea Pessina, Kristian Spilling, Juan Manuel González-Olalla, Luca Zoccarato, Kasia Piwosz, Martina Hanusová, Petr Znachor, Lior Guttman, Lívia Kolesár Fecskeová, Michal Koblížek, Ana Vrdoljak, Thijs Frenken, R. Michael L. McKay, Danijela Šantić, Tom Reich |
|---|---|
| Přispěvatelé: | Aquatic Ecology (AqE) |
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
Light
phytoplankton-bacteria couplingaerobic anoxygenic phototrophic bacteriabacterial community compositionAAP community composition lcsh:QR1-502 Fresh Water Bacterial growth Photosynthesis Bacterial Physiological Phenomena phytoplankton-bacteria coupling Photoheterotroph Microbiology lcsh:Microbiology 03 medical and health sciences bacterial community composition VDP::Matematikk og Naturvitenskap: 400::Basale biofag: 470 AAP community composition Seawater Food science Molecular Biology Ecosystem 030304 developmental biology aerobic anoxygenic phototrophic bacteria 2. Zero hunger 0303 health sciences Phototroph 030306 microbiology Chemistry Microbiota Anoxygenic photosynthesis QR1-502 Bacteria Aerobic Light intensity Phototrophic Processes International Aerobic anoxygenic phototrophic bacteria Plan_S-Compliant_OA Erratum Energy source |
| Zdroj: | mSphere, Vol 5, Iss 4 (2020) mSphere mSphere, 5. American Society for Microbiology mSphere, Vol 5, Iss 4, p e00354-20 (2020) |
| ISSN: | 2379-5042 |
| DOI: | 10.1128/mSphere.00354-20 |
| Popis: | Phytoplankton is a key component of aquatic microbial communities, and metabolic coupling between phytoplankton and bacteria determines the fate of dissolved organic carbon (DOC). Yet, the impact of primary production on bacterial activity and community composition remains largely unknown, as, for example, in the case of aerobic anoxygenic phototrophic (AAP) bacteria that utilize both phytoplankton-derived DOC and light as energy sources. Here, we studied how reduction of primary production in a natural freshwater community affects the bacterial community composition and its activity, focusing primarily on AAP bacteria. The bacterial respiration rate was the lowest when photosynthesis was reduced by direct inhibition of photosystem II and the highest in ambient light condition with no photosynthesis inhibition, suggesting that it was limited by carbon availability. However, bacterial assimilation rates of leucine and glucose were unaffected, indicating that increased bacterial growth efficiency (e.g., due to photoheterotrophy) can help to maintain overall bacterial production when low primary production limits DOC availability. Bacterial community composition was tightly linked to light intensity, mainly due to the increased relative abundance of light-dependent AAP bacteria. This notion shows that changes in bacterial community composition are not necessarily reflected by changes in bacterial production or growth and vice versa. Moreover, we demonstrated for the first time that light can directly affect bacterial community composition, a topic which has been neglected in studies of phytoplankton-bacteria interactions. IMPORTANCE Metabolic coupling between phytoplankton and bacteria determines the fate of dissolved organic carbon in aquatic environments, and yet how changes in the rate of primary production affect the bacterial activity and community composition remains understudied. Here, we experimentally limited the rate of primary production either by lowering light intensity or by adding a photosynthesis inhibitor. The induced decrease had a greater influence on bacterial respiration than on bacterial production and growth rate, especially at an optimal light intensity. This suggests that changes in primary production drive bacterial activity, but the effect on carbon flow may be mitigated by increased bacterial growth efficiencies, especially of light-dependent AAP bacteria. Bacterial activities were independent of changes in bacterial community composition, which were driven by light availability and AAP bacteria. This direct effect of light on composition of bacterial communities has not been documented previously. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|