Victoria Calatrava

University of Córdoba | UCO · Department of Biochemistry and Molecular Biology

Interactions between algae and bacteria are ubiquitous and play fundamental roles in nutrient cycling and biomass production. Recent studies have shown that the plant auxin indole acetic acid (IAA) can mediate chemical crosstalk between algae and bacteria, resembling its role in plant-bacterial associations. Here, we report a mechanism for algal ex...

Nitrogen is a key nutrient for land plants and phytoplankton in terrestrial and aquatic ecosystems. The model alga Chlamydomonas reinhardtii can grow efficiently on several inorganic nitrogen sources (e.g. ammonium, nitrate, nitrite) as well as many amino acids. In this study, we show that Chlamydomonas is unable to use proline, hydroxyproline, and...

Significance Primary endosymbiosis allowed the evolution of complex life on Earth. In this process, a prokaryote was engulfed and retained in the cytoplasm of another microbe, where it developed into a new organelle (mitochondria and plastids). During organelle evolution, genes from the endosymbiont are transferred to the host nuclear genome, where...

The increase in the global population and industrial activities has led to an extensive use of water, the release of wastewater, and overall contamination of the environment. To address these issues, efficient treatment methods have been developed to decrease wastewater nutrient content and contaminants. Microalgae are a promising tool as a sustain...

Microbial mats are stratified communities often dominated by unicellular and filamentous phototrophs within an exopolymer matrix. It is challenging to quantify the dynamic responses of community members in situ as they experience steep gradients and rapid fluctuations of light. To address this, we developed a binary consortium using two representat...

Primary endosymbiosis between a cyanobacterium and a protist marked the origin of photosynthetic eukaryotes, profoundly impacting the history of life on our planet. This event occurred 1.6–2.1 Bya and gave rise to the putative single common ancestor of the Archaeplastida (i.e., glaucophytes, red algae, and green algae plus land plants). A second in...

The photosynthetic amoeba, Paulinella provides a recent (ca. 120 Mya) example of primary plastid endosymbiosis. Given the extensive data demonstrating host lineage‐driven endosymbiont integration, we analysed nuclear genome and transcriptome data to investigate mechanisms that may have evolved in Paulinella micropora KR01 (hereinafter, KR01) to mai...

In soil environments where tryptophan may be present due to plant exudation and microbial decay, bacterial indole-3-acetic acid (IAA) biosynthesis from this amino acid can promote plant growth. Chlamydomonas reinhardtii can also convert tryptophan into IAA using the extracellular enzyme LAO1. Accumulation of this auxin may result in algal growth ar...

The stability and harmony of ecological niches rely on intricate interactions between their members. During evolution, organisms have developed the ability to thrive in different environments, taking advantage of each other. Among these organisms, microalgae are a highly diverse and widely distributed group of major primary producers whose interact...

Interactions between algae and bacteria are widespread in aquatic and terrestrial ecosystems and play fundamental roles in nutrient cycling and biomass production. However, the chemical basis for many of these interactions is poorly characterized and understood. Recent studies have shown that the plant auxin indole acetic acid (IAA) can mediate che...

Nitrous oxide (N2O) is a powerful greenhouse gas and an ozone-depleting compound whose synthesis and release have traditionally been ascribed to bacteria and fungi. Although plants and microalgae have been proposed as N2O producers in recent decades, the proteins involved in this process have been only recently unveiled. In the green microalga Chla...

Optimizing light absorption is of paramount importance to photosynthetic organisms. Some photosynthetic microbes have evolved a sophisticated process called phototaxis to move toward or away from a light source.

Endosymbiosis is a relationship between two organisms wherein one cell resides inside the other. This affiliation, when stable and beneficial for the ‘host’ cell, can result in massive genetic innovation with the foremost examples being the evolution of eukaryotic organelles, the mitochondria and plastids. Despite its critical evolutionary role, th...

Nitrogen (N) is an essential constituent of all living organisms and the main limiting macronutrient. Even when dinitrogen gas is the most abundant form of N, it can only be used by fixing bacteria but is inaccessible to most organisms, algae among them. Algae preferentially use ammonium (NH4+) and nitrate (NO3−) for growth, and the reactions for t...

The mitogen activated protein kinases (MAPKs) form part of a signaling cascade through phosphorylation reactions conserved in all eukaryotic organisms. The MAPK cascades are mainly composed by threeproteins, MAPKKKs, MAPKKs and MAPKs. Some signals induce MAPKKK-mediated phosphorylation and activation of MAPKK that phosphorylate and activate MAPK. A...

Free access Link (until March 06, 2019): https://authors.elsevier.com/c/1YOuv7sxn0Rhw1 ABSTRACT: Phytoplankton live under constantly changing environments in which concentrations of inorganic nitrogen can be limiting but organic nitrogen sources (urea, amino acids or peptides) are available. Understanding how algae, as primary producers, assimilat...

Phytoplankton live under constantly changing environments in which concentrations of inorganic nitrogen can be limiting but organic nitrogen sources (urea, amino acids or peptides) are available. Understanding how algae, as primary producers, assimilate organic nitrogen is of eco-physiological importance although such studies are rare. Given geneti...

All eukaryotic molybdenum (Mo) enzymes contain in their active site a Mo Cofactor (Moco), which is formed by a tricyclic pyranopterin with a dithiolene chelating the Mo atom. Here, the eukaryotic Moco biosynthetic pathway and the eukaryotic Moco enzymes are overviewed, including nitrate reductase (NR), sulfite oxidase, xanthine oxidoreductase, alde...

The green alga Chlamydomonas is a valuable model system capable of assimilating different forms of nitrogen (N). Nitrate (NO3-) has a relevant role in plant-like organisms, first as a nitrogen source for growth and second as a signalling molecule. Several modules are necessary for Chlamydomonas to handle nitrate, including transporters, nitrate red...

The NRT2 transporters mediate High Affinity Nitrate/NitriteTransport (HAN/NiT), which are essential for nitrogen acquisition from these inorganic forms. The NRT2 proteins are encoded by a multigene family in plants, and contain 12 transmembrane-spanning domains. Chlamydomonas reinhardtii has six NRT2, two of which (NRT2.5 and NRT2.4) are located in...