Hydrogen Dynamics in Trichodesmium Colonies and Their Potential Role in Mineral Iron Acquisition

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388971%3A_____%2F19%3A00518292" target="_blank" >RIV/61388971:_____/19:00518292 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.frontiersin.org/articles/10.3389/fmicb.2019.01565/full" target="_blank" >https://www.frontiersin.org/articles/10.3389/fmicb.2019.01565/full</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3389/fmicb.2019.01565" target="_blank" >10.3389/fmicb.2019.01565</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Hydrogen Dynamics in Trichodesmium Colonies and Their Potential Role in Mineral Iron Acquisition

Popis výsledku v původním jazyce

N-2-fixing cyanobacteria mediate H-2 fluxes through the opposing processes of H-2 evolution, which is a by-product of the N-2 fixation reaction, and H-2 uptake, which is driven by uptake hydrogenases. Here, we used microelectrodes to characterize H-2 and O-2 dynamics in single natural colonies of the globally important N-2 fixer Trichodesmium collected from the Gulf of Eilat. We observed gradually changing H-2 dynamics over the course of the day, including both net H-2 evolution and net H-2 uptake, as well as large differences in H-2 fluxes between individual colonies. Net H-2 uptake was observed in colonies amended with H-2 in both light and dark. Net H-2 evolution was recorded in the light only, reflecting light-dependent N-2 fixation coupled to H-2 evolution. Both net H-2 evolution and H-2 uptake rates were higher before 2 pm than later in the day. These pronounced H-2 dynamics in the morning coincided with strong net O-2 uptake and the previously reported diel peak in N-2 fixation. Later in the afternoon, when photosynthesis rates determined by O-2 measurements were highest, and N-2 fixation rates decrease according to previous studies, the H-2 dynamics were also less pronounced. Thus, the observed diel variations in H-2 dynamics reflect diel changes in the rates of O-2 consumption and N-2 fixation. Remarkably, the presence of H-2 strongly stimulated the uptake of mineral iron by natural colonies. The magnitude of this effect was dependent on the time of day, with the strongest response in incubations that started before 2 pm, i.e., the period that covered the time of highest uptake hydrogenase activity. Based on these findings, we propose that by providing an electron source for mineral iron reduction in N-2-fixing cells, H-2 may contribute to iron uptake in Trichodesmium colonies.

Název v anglickém jazyce

Hydrogen Dynamics in Trichodesmium Colonies and Their Potential Role in Mineral Iron Acquisition

Popis výsledku anglicky

N-2-fixing cyanobacteria mediate H-2 fluxes through the opposing processes of H-2 evolution, which is a by-product of the N-2 fixation reaction, and H-2 uptake, which is driven by uptake hydrogenases. Here, we used microelectrodes to characterize H-2 and O-2 dynamics in single natural colonies of the globally important N-2 fixer Trichodesmium collected from the Gulf of Eilat. We observed gradually changing H-2 dynamics over the course of the day, including both net H-2 evolution and net H-2 uptake, as well as large differences in H-2 fluxes between individual colonies. Net H-2 uptake was observed in colonies amended with H-2 in both light and dark. Net H-2 evolution was recorded in the light only, reflecting light-dependent N-2 fixation coupled to H-2 evolution. Both net H-2 evolution and H-2 uptake rates were higher before 2 pm than later in the day. These pronounced H-2 dynamics in the morning coincided with strong net O-2 uptake and the previously reported diel peak in N-2 fixation. Later in the afternoon, when photosynthesis rates determined by O-2 measurements were highest, and N-2 fixation rates decrease according to previous studies, the H-2 dynamics were also less pronounced. Thus, the observed diel variations in H-2 dynamics reflect diel changes in the rates of O-2 consumption and N-2 fixation. Remarkably, the presence of H-2 strongly stimulated the uptake of mineral iron by natural colonies. The magnitude of this effect was dependent on the time of day, with the strongest response in incubations that started before 2 pm, i.e., the period that covered the time of highest uptake hydrogenase activity. Based on these findings, we propose that by providing an electron source for mineral iron reduction in N-2-fixing cells, H-2 may contribute to iron uptake in Trichodesmium colonies.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10606 - Microbiology

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2019

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Frontiers in Microbiology

ISSN

1664-302X

e-ISSN

—

Svazek periodika

10

Číslo periodika v rámci svazku

JUL 10 2019

Stát vydavatele periodika

CH - Švýcarská konfederace

Počet stran výsledku

12

Strana od-do

1565

Kód UT WoS článku

000474750800001

EID výsledku v databázi Scopus

2-s2.0-85069540664