A research of the Universitat proves the adaptation ability of microorganisms in extreme conditions

The fieldwork - made on nine solar panels situated in the three campuses of the Universitat- suggests that the microbial community existent in the photovoltaic panels is more similar to that living in a warm or polar desert, to that living in a Mediterranean city like Valencia. The fact that many bacteria identified in the research can have important biotechnological implications has also been brought to light.

According to the researchers, the studied Biocoenosis (community of organisms which occupy a defined territory by which they are mutually conditioned to survive), “is more similar to that in the deserts than to any human ecosystem or urban microbial ecosystem”. The work is the first approach which gives as a result a highly diverse microbial community, studied in solar panels. A recently published study has proved the limited diversity of the microbial community in the solar panels in Brazil, including some fungi which even obstructed the efficiency of the panels.

The fieldwork in the Universitat shows that this microbial community existent in Valencia “has different proteomic profiling during the day and the night; it is dominated by the red pigments and adapts to resist cycles of high temperatures, desiccation and solar radiation”.

The research, preprinted in the Biology platform bioRxiv and open to comments and contributions, is signed by Pedro Dorado-Morales (Cavanilles Institute); Cristina Vilanova (Biopolis, Science and Technology Park of the Universitat de València); Juli Peretó (Department of Biochemistry and Molecular Biology); Francisco M. Codoñer (Lifesequencing, Science Park); Daniel Ramon (Biopolis, Science Park); and Manuel Porcar (Cavanilles Institute and University of Valencia General Foundation).

According to researcher Manuel Porcar, “the most abundant bacteria (‘Deinococcus’, ‘Hymenobacter’, etc.) are not usually found in urban environments, but are found in warm or cold deserts (like Antarctica or Sonora Desert, in Mexico). In our roofs, we have found thus, a unique microbial community characterised by its diversity and because it is the first intra-urban microbial desert”.

Furthermore, there is a high resistance of microorganism s to high concentration of salt; moderate and strong resistance to low acidity and solar light or heat. In the work 800 different species were identified in the photovoltaic solar panels of the Unviersitat, and a year later, in 2014, around 500.

Manuel Porcar explains that a systematic sampling of the photovoltaic panels was made, by day (with the panels at more than 50ºC) and at night. “We have spread its surface with a sort of sterile windscreen wiper. After that, we have verified the resistance to difficult conditions of the plaques (high irradiation, temperature, dehydration) of isolated bacteria, and we have compared the proteome (protein group) during the day and the night. We could say that, up to date, it is the first intra-urban microbial desert found, which is a clear sign of the natural selection of living creatures in order to adapt to the different conditions in life”.

Pedro Dorado-Morales, Cristina Vilanova, Juli Peretó, Francisco M. Codoñer, Daniel Ramón and Manuel Porcar.

‘A highly diverse, desert-like microbial biocenosis on solar panels in a Mediterranean city’

bioRxvid preprint first posted online October 22, 2015. Doi: http://dx.doi.org/10.1101/029660