Fluctuation analysis to select for Samarium bio-uptaking microalgae clones the repurposing of a classical evolution experiment

• Published in: Ecotoxicology and environmental safety Vol. 215; p. 112134
• Main Authors: Martínez-Alesón García, Paloma, García-Balboa, Camino, Romero-López, Julia, López-Rodas, Victoria, Costas, Eduardo, Baselga-Cervera, Beatriz
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Inc 01.06.2021; Elsevier
• Subjects: Adaptation; Biological Transport; Biouptake; Chlamydomonas reinhardtii; Clone Cells - chemistry; Metals - metabolism; Metals, Rare Earth - analysis; Microalgae - metabolism; Rare earth elements; Samarium; Samarium - metabolism; Toxicity; Water Pollutants, Chemical - metabolism; BLM; EEE; Toxicity; WB; EDTA; Biouptake; REE; Rare earth elements; Chlamydomonas reinhardtii; ICP-MS; Samarium; DB; Adaptation
• ISSN: 0147-6513; 1090-2414
• DOI: 10.1016/j.ecoenv.2021.112134

Rare Earth Elements (REE) increasing demand prompts the research of biotechnological approaches to exploit secondary resources. We made use of the adapted Fluctuation analyses experiment to obtain Chlamydomonas reinhardtii ChlA strains resistant to Samarium (Sm) as the reference REE. The starting hypothesis was that adaptation to metal-containing media leads to an enhanced metal uptake. ChlA was able to adapt to 1.33·10−4 Sm M and pH~3 by pre-existing genetic variability, allowing the evolutionary rescue of 13 of the 99 populations studied. The rescuing resistant genotypes presented a mutation rate of 8.65·10−7 resistant cells per division. The resulting resistant population contradicted the expected fitness cost associated with the adaptation to Sm, selection resulted in larger and faster-growing resistant cells. Among the three isolated strains studied for Sm uptake, only one presented uplifted performance compared to the control population (46.64 μg Sm gˉ¹ of wet biomass and 3.26·10−7 ng Sm per cell, mainly bioaccumulated within the cells). The selection of microalgae strains with improved tolerance to REEs by this methodology could be a promising solution for REES sequestration. However, increased tolerance can be independent or have negative effects on uptake performance and cellular features studied are not directly correlated with the metal uptake. Repurposing a classic laboratory evolution experiment to select for microalgae Samarium adapted strains for metals recovery and biotechnology approaches. All data generated or analyzed during this study are included in this published article (and its raw files). [Display omitted] •Repurpose Fluctuation analysis as a mechanism to select resistant microalgae.•Selection to Sm resistance resulted in larger and faster-growing resistant cells.•Morphological and physiological diversity are present between resistance strains.•Adaptation to Sm in acid pH environment not necessarily enhanced metal uptake.•Physiological features can be useful to select or discard biotechnological strains.