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Genomic DNA of Nostoc Commune (Cyanobacteria) Becomes Covalently Modified During Long-Term (Decades) Desiccation But Is Protected From Oxidative Damage and Degradation



B Shirkey, N J. McMaster, Sue C. Smith, D J. Wright, H Rodriguez, Pawel Jaruga, M Birincioglu, R F. Helm, M Potts


Genomic DNA of Nostoc commume (Cyanobacteria) became covalently modified during decades of desiccation. Amplification of gene loci from desiccated cells required pretreatment of DNA with N-phenacylthiazolium bromide; a reagent that cleaves DNA- and protein-linked advanced glycosylation endproducts. DNA from 13-year desiccated cells did not show any higher levels of the commonly studied oxidatively-modified DNA damage biomarkers 8-hydroxyguanine, 8-hydroxyadenine, and 5-hydroxyuracil, compared to commercially available calf thymus DNA. Different patterns of amplification products were obtained with DNA from desiccated/rehydrating cells and a liquid culture derived from the dried material, using the same set of primers. In contrast, a reproducible fingerprint was obtained, irrespective of time of rehydration of the DNA, using a primer (5'GWCWATCGCC 3') based upn a highly-iterated palindromic (HIP) repeat sequence present in the genome. In vitro, the desiccation of cccDNA lead to loss of supercoiling, aggregation, loss of resolution during agarose gel electrophoresis, and loss of transformation and transfection efficiency. These changes were minimized when DNA was desiccated and stored in the presence of trehalose, a non-reducing disaccharide present in Nostoc colonies. The response of the N. commune genome to desiccation is different from the response of the genomes of cyanobacteriaand Deinococcus radiodurans to ionizing radiation.
Nucleic Acids Research


cyanobacteria, desiccation, DNA modification, DNA stability


Shirkey, B. , McMaster, N. , Smith, S. , Wright, D. , Rodriguez, H. , Jaruga, P. , Birincioglu, M. , Helm, R. and Potts, M. (2003), Genomic DNA of Nostoc Commune (Cyanobacteria) Becomes Covalently Modified During Long-Term (Decades) Desiccation But Is Protected From Oxidative Damage and Degradation, Nucleic Acids Research (Accessed May 20, 2024)


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Created June 14, 2003, Updated October 12, 2021