Bioprospecting the solar panel microbiome: high-throughput screening for antioxidant bacteria in aCaenorhabditis elegansmodel

Abstract

Microbial communities that are exposed to sunlight typically share a series of adaptations to deal with the radiation they are exposed to, including efficient DNA repair systems, pigment production and protection against oxidative stress, which makes these environments good candidates for the search of novel antioxidant microorganisms. In this research project, we isolated potential antioxidant pigmented bacteria from a dry and highly-irradiated extreme environment: solar panels. High-throughput in vivo assays using Caenorhabiditis elegans as an experimental model demonstrated the high antioxidant and ultravioletprotection properties of these bacterial isolates that proved to be rich in carotenoids. Our results suggest that solar panels harbor a microbial community that includes strains with potential applications as antioxidants.

Microbial communities of the Mediterranean rocky shore: ecology and biotechnological potential of the sea‐land transition

“…A collection of both positive and negative controls (in terms of theoretical antioxidant activity) were tested using both assays (H 2 O 2 and DPPH). PS1, PS21 and PS75 ( P. glaciei 423, 97.38% ID; Rhodobacter maris JA276, 98.89% ID; and Bacillus megaterium NBRC 15308, 100% ID respectively) were the three control strains selected, all of them recovered from solar panels and previously tested in C. elegans for in vivo protection against oxidative stress (Tanner et al ., ). Three different strains of E. coli were chosen as negative controls (JM109, BH101, DH5α).…”

“…Surprisingly, the control samples P. glaciei and JM109 did not display the expected effect in terms of antioxidant activity. On one hand, P. glaciei was expected to be one of the most antioxidant isolates, as its antioxidant activity was demonstrated in previous in vivo assays in C. elegans (Tanner et al ., ) and in the H 2 O 2 assay. Nevertheless, it was the worst strain in terms of DPPH scavenging.…”

“…Two strains were used as controls for the assay: PS1 ( Planomicrobium glaciei 423, 97.38% ID) and Escherichia coli JM109 as a positive and negative control for antioxidant activity respectively. Planomicrobium glaciei is a pigmented microorganism whose antioxidant activity has previously been reported in vivo using a Caenorhabditis elegans model (Tanner et al ., ).…”

Kineococcus vitellinus sp. nov., Kineococcus indalonis sp. nov. and Kineococcus siccus sp. nov., Isolated Nearby the Tabernas Desert (Almería, Spain)

“…The objective of the study was to characterize in detail the microbial communities from the Tabernas Desert (Almería, Spain), with particular emphasis in the isolation of extremophilic bacteria. The bacterial strains isolated from similar environmental niches, such as solar panels or the intertidal coastal zone, are able to tolerate UV radiation, and could thus be potentially useful in the synthesis of antioxidant compounds [ 13 , 14 ]. Among them, pigments such as carotenoids are particularly valuable for the biotechnological and pharmaceutical industries.…”