Projects

Group Research Projects

Anaerobic degradation of aromatic compounds

We are carrying out pioneer studies through molecular biology and omics-based approaches on the anaerobic degradation of aromatic compounds in bacteria, by using Azoarcus sp. CIB, a Beta-Proteobacterium able to mineralize aromatic hydrocarbons such as toluene and m-xylene, as model system. Thus, we have characterized:

  1. New anaerobic central pathways, e.g., mbd pathway for m-xylene degradation.
  2. New signaling mechanisms, such as that based on the c-di-GMP second messenger, and the role of mobile integrative-conjugative elements, in the adaptation to the degradation of aromatic hydrocarbons.
  3. New regulatory circuits that respond to the redox state of the cell and modulate the expression of the catabolic pathways.
  4. New families of transcriptional regulators, e.g., the BzdR family, that allowed us to ascertain the evolutionary origin of some prokaryotic regulators.

We are designing, through systems biology and metabolic engineering approaches, optimized Azoarcus sp. CIB strains for degradation of aromatic compounds and their conversion to added value products such as bioplastics (polyhydroxybutyrate).

 

Aerobic degradation of aromatic compounds

A second area of emphasis involves the metabolically versatile aerobic G-Proteobacterium Pseudomonas putida. P. putida is an excellent model organism for studying bacterial metabolism and signal transduction cascades involved in the regulation of aromatic degradation pathways. The role of dinucleotides and that of the global and specific regulators in the regulatory networks that control the aerobic degradation of aromatics in Pseudomonas putida KT2440, a model G-Proteobacterium that has been extensively used in environmental biotechnology, constitute another research topic in our team.

 

Plant-bacteria beneficial interactions

Another research line is devoted to explore the endophyte lifestyle of Azoarcus sp. CIB when this strain interacts with plants, and then to exploit this interaction for endophytoremediaton.

 

Syngas bioconversion

As an example of more sustainable and environmentally-friendly bioprocesses, we are performing synthetic biology approaches for the efficient bioconversion of some compounds, e.g. CO, present in the synthetic gas generated in biomass recycling to added value products.

 

Sonotaxis. How bacteria detect sound waves in the audio frequency range?

Bacteria are characterized by their ability for interacting and become adapted to their surrounding environment. To this aim, they have developed various mechanisms to detect both chemical and physical stimuli and to respond in very different ways to these stimuli. Nowadays we know quite well the molecular basis of most of these detection and response mechanisms. However, very little is known on whether bacteria are able to detect and respond to one of the most common physical stimuli present in the environment, i.e., the sound waves in the audio frequency range (20 to 20000 Hz). Therefore, this project aims to develop different experiments to elucidate precisely and reproducibly the effects of audible sound waves in bacteria, as well as the molecular mechanisms underlying the detection and response to these stimuli. The few previous data on the effects of audible sound waves in the development of microorganisms are not sufficiently supported and, in any case, the underlying molecular mechanisms used to detect these stimuli are not known. Therefore, this project will develop firstly a working method to certifying the existence of this effect using perfectly controlled and reproducible acoustic devices, and employing different bacteria and culture media. Once the effect of the sonic waves is confirmed, we will determine the molecular basis of the mechanism of action using omics and genetic engineering technologies. Although the heterodoxy and project risks are high, the profits can be very large from different points of view, i.e., biotechnological, clinical and environmental. If it is demonstrated that bacteria have developed specific molecular mechanisms to detect and respond to the sound waves, the use of these sonic stimuli will facilitate to modify and control the bacterial metabolism by using very simple and safe acoustic devices. You can visit us in our Facebook!

 

 

System level analysis of the metabolic robustness in bacteria.

The understanding of the genotype-phenotype relationship is a fundamental biological question, widely studied, but still not understood in all its dimension. The existence of emergent systems properties largely hampers the lineality of this relationship making it mandatory the study of such properties to fully understand the biological systems. The robustness, understood as the property that allows the systems to maintain their functions despite external and internal perturbations, is a system-level phenomenon ubiquitously observed in living systems, however it is still poorly understood at molecular level. We aim to unravel the molecular mechanisms providing robustness to bacterial systems through an integrative biology approach including microbiological, and molecular and systems biology strategies. See more details here

 

emCIB Lab