The phenomenon was first reported in 1954 by Hazel D. Barner and Seymour S. Cohen in Escherichia coli when thymine-requiring mutants of the bacteria lost viability when grown in a medium lacking thymine but containing other essential nutrients.[4][5] Subsequently, this discovery led to the development of theories to explain the mechanism of action of several pyrimidine analogs that targeted thymine metabolism in bacteria and tumor cells.[5][6] The phenomenon was commonly attributed to "unbalanced growth" wherein cells continued fundamental processes of RNA transcription, protein synthesis and metabolism in the absence of DNA replication.[7] However, nutrient starvation does not generally kill cells to the extent observed in cells that lack thymine. The molecular mechanism of thymineless death remains unknown;[1] DNA breaks were observed during thymineless death, which could explain the killing.[8][9] Possible pathways involved with the killing mechanism include: replication initiation,[8][10] breakage of ongoing replication forks,[11] futile DNA repair,[9] replication origin destruction,[12] and an addiction module.[13]
References
^ abcAhmad, S. I.; Kirk, S. H.; Eisenstark, A. (October 1998). "Thymine Metabolism and Thymineless Death in Prokaryotes and Eukaryotes". Annual Review of Microbiology. 52: 591–625. doi:10.1146/annurev.micro.52.1.591. PMID9891809.
^Longley, D. B.; Harkin, D. P.; Johnston, P. G. (2003). "5-Fluorouracil: Mechanisms of action and clinical strategies". Nature Reviews Cancer. 3 (5): 330–338. doi:10.1038/nrc1074. PMID12724731. S2CID4357553.
^Friedman, M. A.; Sadée, W. (1978). "The fluoropyrimidines: Biochemical mechanisms and design of clinical trials". Cancer Chemotherapy and Pharmacology. 1 (2): 77–82. doi:10.1007/bf00254040. PMID373913. S2CID10958670.
^ abMartín, C. M.; Guzmán, E. C. (2011). "DNA replication initiation as a key element in thymineless death". DNA Repair. 10 (1): 94–101. doi:10.1016/j.dnarep.2010.10.005. PMID21074501.
^ abNakayama, K.; Kusano, K.; Irino, N.; Nakayama, H. (1994). "Thymine starvation-induced structural changes in Escherichia coli DNA. Detection by pulsed field gel electrophoresis and evidence for involvement of homologous recombination". Journal of Molecular Biology. 243 (4): 611–620. doi:10.1016/0022-2836(94)90036-1. PMID7966286.