Photoacclimation of the polar diatom Chaetoceros neogracilis at low temperature

Type : ACL
Nature : Production scientifique
Au bénéfice du Laboratoire : Non
Statut de publication : Publié
Année de publication : 2022
Auteurs (9) : LACOUR Thomas LARIVIÈRE Jade FERLAND Joannie MORIN Pascal GRONDIN P,l DONAHER Natalie COCKSHUTT A CAMPBELL Douglas,andrew BABIN Marcel
Revue scientifique : Plos One
Volume : 17
Fascicule : 9
Pages :
DOI : 10.1371/journal.pone.0272822
URL : -
Abstract : Polar microalgae face two major challenges: 1- growing at temperatures (-1.7 to 5 degrees C) that limit enzyme kinetics; and 2- surviving and exploiting a wide range of irradiance. The objective of this study is to understand the adaptation of an Arctic diatom to its environment by studying its ability to acclimate to changes in light and temperature. We acclimated the polar diatom Chaetoceros neogracilis to various light levels at two different temperatures and studied its growth and photosynthetic properties using semi-continuous cultures. Rubisco content was high, to compensate for low catalytic rates, but did not change detectably with growth temperature. Contrary to what is observed in temperate species, in C. neogracilis, carbon fixation rate (20 min C-14 incorporation) equaled net growth rate (mu) suggesting very low or very rapid (< 20 min) re-oxidation of the newly fixed carbon. The comparison of saturation irradiances for electron transport, oxygen net production and carbon fixation revealed alternative electron pathways that could provide energy and reducing power to the cell without consuming organic carbon which is a very limiting product at low temperatures. High protein contents, low re-oxidation of newly fixed carbon and the use of electron pathways alternative to carbon fixation may be important characteristics allowing efficient growth under those extreme environmental conditions.
Mots-clés : -
Commentaire : -
Tags : -
Fichier attaché : -
Citation :
Lacour T, Larivière J, Ferland J, Morin P, Grondin PL, Donaher N, Cockshutt A, Campbell DA, Babin M (2022) Photoacclimation of the polar diatom Chaetoceros neogracilis at low temperature. Plos One 17 | doi: 10.1371/journal.pone.0272822