Search results for "YLL"

Changes in lipid and carotenoid metabolism in Chlamydomonas reinhardtii during induction of CO2-concentrating mechanism: Cellular response to low CO2…

2020

Photosynthetic organisms strictly depend on CO2 availability and the CO2:O2 ratio, as both CO2/O2 compete for catalytic site of Rubisco. Green alga Chlamydomonas reinhardtii, can overcome CO2 shortage by inducing CO2-concentrating mechanism (CCM). Cells transferred to low-CO2 are subjected to light-driven oxidative stress due to decrease in the electron sink. Response to environmental perturbations is mediated to some extent by changes in the lipid and carotenoid metabolism. We thus hypothesize that when cells are challenged with changes in CO2 availability, changes in the lipidome and carotenoids profile occur. These changes expected to be transient, when CCM is activated, CO2 limitation w…

Extraction and Analysis of Carotenoids from Escherichia coli in Color Complementation Assays

2017

A common method to investigate the function of genes putatively involved in carotenoid biosynthesis is the so called color complementation assay in Escherichia coli (see, e.g., Cunningham and Gantt, 2007). In this assay, the gene under investigation is expressed in E. coli strains genetically engineered to synthesize potential carotenoid substrates, followed by analysis of the pigment changes in the carotenogenic bacteria via high-performance liquid chromatography (HPLC). Two crucial steps in this method are (i) the quantitative extraction of the carotenoids out of E. coli and (ii) the reproducible and complete separation of the pigments by HPLC. Here, we present a protocol for the extracti…

Leaf anatomy does not explain apparent short-term responses of mesophyll conductance to light and CO2 in tobacco

2018

Mesophyll conductance to CO2 (gm ), a key photosynthetic trait, is strongly constrained by leaf anatomy. Leaf anatomical parameters such as cell wall thickness and chloroplast area exposed to the mesophyll intercellular airspace have been demonstrated to determine gm in species with diverging phylogeny, leaf structure and ontogeny. However, the potential implication of leaf anatomy, especially chloroplast movement, on the short-term response of gm to rapid changes (i.e. seconds to minutes) under different environmental conditions (CO2 , light or temperature) has not been examined. The aim of this study was to determine whether the observed rapid variations of gm in response to variations of…

Flashing light emitting diodes (LEDs) induce proteins, polyunsaturated fatty acids and pigments in three microalgae

2020

As the periodic emission of light pulses by light emitting diodes (LEDs) is known to stimulate growth or induce high value biocompounds in microalgae, this flashing light regime was tested on growth and biochemical composition of the microalgae Nannochloropsis gaditana, Koliella antarctica and Tetraselmis chui. At low flashing light frequencies (e.g., 5 and 50 Hz, Duty cycle = 0.05), a strain-dependent growth inhibition and an accumulation of protein, polyunsaturated fatty acids, chlorophyll or carotenoids (lutein, β-carotene, violaxanthin and neoxanthin) was observed. In addition, a 4-day application of low-frequency flashing light to concentrated cultures increased productivities of eicos…

Simultaneous speciation in the European high mountain flowering plant genus Facchinia (Minuartia s.l., Caryophyllaceae) revealed by genotyping-by-seq…

2017

Understanding the relative importance of different mechanisms of speciation in a given lineage requires fully resolved interspecific relationships. Using Facchinia, a genus of seven species centred in the European Alps, we explore whether the polytomy found by Sanger sequencing analyses of standard nuclear (ITS) and plastid markers (trnQ-rps16) is a hard or soft polytomy by substantially increasing the amount of DNA sequence data, generated by genotyping-by-sequencing. In comparison to 142 phylogenetically informative sites in the Sanger sequences the GBS sequences yielded 3363 phylogenetically informative sites after exclusion of apparently oversaturated SNPs. Maximum parsimony, maximum li…

C3cotyledons are followed by C4leaves: intra-individual transcriptome analysis ofSalsola soda(Chenopodiaceae)

2016

The genome of Salsola soda allows a transition from C3 to C4 photosynthesis. A developmental transcriptome series revealed novel genes showing expression patterns similar to those encoding C4 proteins.

Parameterising a public good: how experiments on predation can be used to predict cheat frequencies

2016

Chemical defence is superficially easy to understand as a means for individuals to protect themselves from enemies. The evolution of chemical defence is however potentially complex because such defences may cause the generation of a public good, protecting members of the population as a whole as well as individuals that deploy toxins defensively. If a public good of protection exists, it may be exploited and degraded by “cheats” that do not invest in defence. This can in turn lead to complex frequency (and density) dependent effects in toxin evolution. To investigate this we used ecologically relevant predators (Great tits, Parus major) and examined how individual and public benefits vary d…

A new hybrid in the genus <em>Anthyllis</em> (Loteae-Leguminosae) from the eastern Iberian Peninsula

2016

We describe a new nothotaxon for the genus Anthyllis (Loteae- Leguminosae), A. . currasii P.P. Ferrer, Roselló & Guara, as result of natural interbreeding between A. cytisoides (Lag.) Pau and A. lagascana Benedí. It has been located at Monte de La Cañada, in Paterna (Valencia, Spain). This new hybrid is compared morphologically with its parents and the rest of nothotaxa described hitherto for the genus in the Iberian Peninsula, analysing the main diagnostic characters. The existence of the nothotaxa A. . fortuita Guara & P.P. Ferrer and A. . currasii implies the creation of the new nothosubgenus Ternijovis P.P. Ferrer, Roselló & Guara. A map of the known and documented distribut…

Session 10 Photosynthesis

1994

Colonization of Plant Roots by Pseudomonads and AM Fungi: A Dynamic Phenomenon, Affecting Plant Growth and Health

2008

Because of their enormously large range of plant hosts and role in plant nutrition, arbuscular mycorrhizal (AM) fungi represent an extraordinarily fascinating field of study. Plant growth promotion effects by AM fungi were described as early as 1900 (Sthal 1900) and several data obtained in the second half of the last century support the idea that these microrganisms can act as biocontrol agents (BCA). The extent of root colonization is variable in different plants and under different environmental conditions (Giovannetti and Hepper 1985). Some effects of AM colonization on plants have been reported to be dependent on the degree of root colonization, while others have not. Root exudation an…