The effect of lanthanides on photosynthesis, growth, and chlorophyll profile of the green alga Desmodesmus quadricauda.
Lanthanides (La, Gd, Nd, Ce) accumulated in the green alga Desmodesmus quadricauda but their intracellular localizations were distinctly different: lanthanum and gadolinium were localized in cytoplasm, while neodymium and cerium were in the chloroplast. The effect of lanthanum and neodymium, as representatives of these two groups, on growth, chlorophyll content and photosynthetic rate at different light intensities was studied. At the lowest light intensity used (50 µmol photons m-2s-1), in the presence of lanthanides (Nd), growth was enhanced by as much as 36 % over lanthanide free control, and the photosynthetic rate increased by up to 300 %. At high light intensities (238, 460, and 750 µmol photons m-2s-1), photosynthetic rate increased markedly, but there was no significant difference between rates in the presence or absence of lanthanides. However, growth, measured as a percentage of dry weight, if compared with lanthanide free control, increased at all light intensities (31, 39, and 20 %, respectively). The total amount of chlorophyll after lanthanide treatment increased by up to 21 % relative to the control culture, mainly due to an increase in the level of chlorophyll b. Addition of lanthanides caused a change in the chlorophyll a/b ratio from 4.583 in control cultivation, to 1.05. Possible mechanisms of lanthanide-induced photosynthetic change, alterations in photosynthetic structures, and increases in growth are discussed and compared with findings in higher plants. The hypothesis that the lanthanide effect could be due to formation of lanthanide-pheophytins was not confirmed as lanthanide pheophytins were not found in D. quadricauda. Furthermore, we have shown that the preferential incorporation of heavy isotopes of magnesium, namely25Mg and26Mg, into chlorophyll during photosynthesis that occurred in controls was diminished in the presence of lanthanides.
Institute of Microbiology of the CAS, Vídeňská 1083, 14220, Prague, Czech Republic.
Tomáš
T
Řezanka
Medical and Pharmaceutical Biotechnology, IMC University of Applied Sciences Krems, Piaristengasse1, A-3500, Krems an der Donau, Austria.
Katrin
K
Kaineder
Medical and Pharmaceutical Biotechnology, IMC University of Applied Sciences Krems, Piaristengasse1, A-3500, Krems an der Donau, Austria.
Dana
D
Mezricky
Institute for Nanomaterials, Advanced Technologies and Innovation, Technical University of Liberec, Studentská 1402/2, 46117, Liberec, Czech Republic.
Michal
M
Řezanka
Laboratory of Cell Cycles of Algae, Centre Algatech, Institute of Microbiology of the CAS, Novohradská 237, Třeboň, 379 81, Czech Republic.
Kateřina
K
Bišová
Laboratory of Cell Cycles of Algae, Centre Algatech, Institute of Microbiology of the CAS, Novohradská 237, Třeboň, 379 81, Czech Republic.
Vilém
V
Zachleder
Laboratory of Cell Cycles of Algae, Centre Algatech, Institute of Microbiology of the CAS, Novohradská 237, Třeboň, 379 81, Czech Republic. milada.vitova@gmail.com.
Milada
M
Vítová
D002734:Chlorophyll / Q000032:analysis* / Q000302:isolation & purification / Q000502:physiology; D000460:Chlorophyta / Q000737:chemistry / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D002736:Chloroplasts / Q000187:drug effects / Q000378:metabolism; D028581:Lanthanoid Series Elements / Q000494:pharmacology*; D010788:Photosynthesis / Q000187:drug effects*
D028581:Lanthanoid Series Elements; D002734:Chlorophyll
Chlorophyll; Green algae; Growth; High-resolution electrospray mass spectrometry; Lanthanides; Magnesium isotopes; Photosynthetic rate