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

Result code in 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>

Result on the web

<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>

Result language

angličtina

Original language name

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

Original language description

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.

Czech name

—

Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10606 - Microbiology

Project

—

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2019

Confidentiality

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

Name of the periodical

Frontiers in Microbiology

ISSN

1664-302X

e-ISSN

—

Volume of the periodical

10

Issue of the periodical within the volume

JUL 10 2019

Country of publishing house

CH - SWITZERLAND

Number of pages

12

Pages from-to

1565

UT code for WoS article

000474750800001

EID of the result in the Scopus database

2-s2.0-85069540664