Adaptive laboratory evolution of cadmium tolerance in Synechocystis sp PCC 6803
Open Access
- 24 July 2018
- journal article
- research article
- Published by Springer Science and Business Media LLC in Biotechnology for Biofuels
- Vol. 11 (1), 205
- https://doi.org/10.1186/s13068-018-1205-x
Abstract
Background: Cadmium has been a significant threat to environment and human health due to its high toxicity and wide application in fossil-fuel burning and battery industry. Cyanobacteria are one of the most dominant prokaryotes, and the previous studies suggested that they could be valuable in removing-Cd2+ from waste water. However, currently, the tolerance to cadmium is very low in cyanobacteria. To further engineer cyanobacteria for the environmental application, it is thus necessary to determine the mechanism that they respond to high concentration of cadmium. Results: In this study, a robust strain of Synechocystis PCC 6803 (named ALE-9.0) tolerant to-CdSO4 with a concentration up to 9.0 mu M was successfully isolated via adaptive laboratory evolution over 802-day continuous passages under cadmium stress. Whole-genome re-sequencing was then performed and nine mutations were identified for the evolved strain compared to the wild-type strain. Among these mutations, a large fragment deletion in slr0454 encoding a cation or drug efflux system protein was found to contribute directly to the resistance to-Cd2+ stress. In addition, five other mutations were also demonstrated related to the improved-Cd2+ tolerance in ALE-9.0. Moreover, the evolved ALE-9.0 strain was found to obtain cross tolerance to some other heavy metals like zinc and cobalt as well as higher resistance to high light. Conclusions: The work here identified six genes and their mutations related to-Cd2+ tolerance in Synechocystis PCC 6803, and demonstrated the feasibility of adaptive laboratory evolution in tolerance modifications. This work also provided valuable information regarding the cadmium tolerance mechanism in Synechocystis PCC 6803, and useful insights for cyanobacterial robustness and tolerance engineering.Funding Information
- National Natural Science Foundation of China (31470217)
This publication has 57 references indexed in Scilit:
- Two RND proteins involved in heavy metal efflux in Caulobacter crescentus belong to separate clusters within proteobacteriaBMC Microbiology, 2013
- Adaptive laboratory evolution – principles and applications for biotechnologyMicrobial Cell Factories, 2013
- Bioremoval capacity of three heavy metals by some microalgae species (Egyptian Isolates)Plant Signaling & Behavior, 2012
- Microbial laboratory evolution in the era of genome‐scale scienceMolecular Systems Biology, 2011
- Cadmium triggers an integrated reprogramming of the metabolism of Synechocystis PCC6803, under the control of the Slr1738 regulatorBMC Genomics, 2007
- Fast cadmium inhibition of photosynthesis in cyanobacteria in vivo and in vitro studies using perturbed angular correlation of γ-raysJBIC Journal of Biological Inorganic Chemistry, 2006
- Analysis of Relative Gene Expression Data Using Real-Time Quantitative PCR and the 2−ΔΔCT MethodMethods, 2001
- The orange carotenoid protein of Synechocystis PCC 6803Biochimica et Biophysica Acta (BBA) - Bioenergetics, 1997
- Sequence Analysis of the Genome of the Unicellular Cyanobacterium Synechocystis sp. Strain PCC6803. II. Sequence Determination of the Entire Genome and Assignment of Potential Protein-coding Regions (Supplement)DNA Research, 1996
- Sequence Analysis of the Genome of the Unicellular Cyanobacterium Synechocystis sp. Strain PCC6803. II. Sequence Determination of the Entire Genome and Assignment of Potential Protein-coding RegionsDNA Research, 1996