Rapid growth rates of aerobic anoxygenic phototrophs in the ocean

Authors

  • Michal Koblížek,

    Corresponding author
    1. Institute of Microbiology CAS, Opatovický mlýn, 379 81 Třeboň, Czech Republic.
    2. Institute of Physical Biology JčU, Zámek 136, 373 33 Nové Hrady, Czech Republic.
      *E-mail koblizek@alga.cz; Tel. (+420) 606 648 405; Fax (+420) 384 721 246.
    Search for more papers by this author
  • Michal Mašín,

    1. Institute of Microbiology CAS, Opatovický mlýn, 379 81 Třeboň, Czech Republic.
    2. Institute of Physical Biology JčU, Zámek 136, 373 33 Nové Hrady, Czech Republic.
    Search for more papers by this author
  • Josephine Ras,

    1. Laboratoire d'Océanographie de Villefranche, BP08 Quai de la Darse 06238, Villefranche-sur-mer, France.
    Search for more papers by this author
  • Alex J. Poulton,

    1. National Oceanography Centre, Southampton, European Way, Southampton SO14 3ZH, UK.
    Search for more papers by this author
  • Ondřej Prášil

    1. Institute of Microbiology CAS, Opatovický mlýn, 379 81 Třeboň, Czech Republic.
    2. Institute of Physical Biology JčU, Zámek 136, 373 33 Nové Hrady, Czech Republic.
    Search for more papers by this author

*E-mail koblizek@alga.cz; Tel. (+420) 606 648 405; Fax (+420) 384 721 246.

Summary

We analysed bacteriochlorophyll diel changes to assess growth rates of aerobic anoxygenic phototrophs in the euphotic zone across the Atlantic Ocean. The survey performed during Atlantic Meridional Transect cruise 16 has shown that bacteriochlorophyll in the North Atlantic Gyre cycles at rates of 0.91–1.08 day−1 and in the South Atlantic at rates of 0.72–0.89 day−1. In contrast, in the more productive equatorial region and North Atlantic it cycled at rates of up to 2.13 day−1. These results suggest that bacteriochlorophyll-containing bacteria in the euphotic zone of the oligotrophic gyres grow at rates of about one division per day and in the more productive regions up to three divisions per day. This is in striking contrast with the relatively slow growth rates of the total bacterial community. Thus, aerobic anoxygenic phototrophs appear to be a very dynamic part of the marine microbial community and due to their rapid growth, they are likely to be larger sinks for dissolved organic matter than their abundance alone would predict.

Ancillary