@article{fdi:010086131,
  title = {{D}iazotrophs are overlooked contributors to carbon and nitrogen export to the deep ocean},
  author = {{B}onnet, {S}ophie and {B}enavides, {M}ar and {L}e {M}oigne, {F}. {A}. {C}. and {C}amps, {M}. and {T}orremocha, {A}. and {G}rosso, {O}. and {D}imier, {C}. and {S}pungin, {D}. and {B}erman-{F}rank, {I}. and {G}arczarek, {L}. and {C}ornejo-{C}astillo, {F}. {M}.},
  editor = {},
  language = {{ENG}},
  abstract = {{D}iazotrophs are widespread microorganisms that alleviate nitrogen limitation in 60% of our oceans, thereby regulating marine productivity. {Y}et, the group-specific contribution of diazotrophs to organic matter export has not been quantified, which so far has impeded an accurate assessment of their impact on the biological carbon pump. {H}ere, we examine the fate of five groups of globally-distributed diazotrophs by using an original combination of mesopelagic particle sampling devices across the subtropical {S}outh {P}acific {O}cean. {W}e demonstrate that cyanobacterial and non-cyanobacterial diazotrophs are exported down to 1000 m depth. {S}urprisingly, group-specific export turnover rates point to a more efficient export of small unicellular cyanobacterial diazotrophs ({UCYN}) relative to the larger and filamentous {T}richodesmium. {P}hycoerythrin-containing {UCYN}-{B} and {UCYN}-{C}-like cells were recurrently found embedded in large (>50 mu m) organic aggregates or organized into clusters of tens to hundreds of cells linked by an extracellular matrix, presumably facilitating their export. {B}eyond the {S}outh {P}acific, our data are supported by analysis of the {T}ara {O}ceans metagenomes collected in other ocean basins, extending the scope of our results globally. {W}e show that, when diazotrophs are found in the euphotic zone, they are also systematically present in mesopelagic waters, suggesting their transport to the deep ocean. {W}e thus conclude that diazotrophs are a significant part of the carbon sequestered in the deep ocean and, therefore, they need to be accounted in regional and global estimates of export.},
  keywords = {{PACIFIQUE} {SUD}},
  booktitle = {},
  journal = {{ISME} {J}ournal},
  volume = {[{E}arly access]},
  numero = {},
  pages = {[12 p.]},
  ISSN = {1751-7362},
  year = {2022},
  DOI = {10.1038/s41396-022-01319-3},
  URL = {https://www.documentation.ird.fr/hor/fdi:010086131},
}