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Max A B Haase Jacek Kominek Dana A Opulente Xing-Xing Shen Abigail L LaBella Xiaofan Zhou Jeremy DeVirgilio Amanda Beth Hulfachor Cletus P Kurtzman Antonis Rokas Chris Todd Hittinger 《Genetics》2021,217(2)
Dollo’s law posits that evolutionary losses are irreversible, thereby narrowing the potential paths of evolutionary change. While phenotypic reversals to ancestral states have been observed, little is known about their underlying genetic causes. The genomes of budding yeasts have been shaped by extensive reductive evolution, such as reduced genome sizes and the losses of metabolic capabilities. However, the extent and mechanisms of trait reacquisition after gene loss in yeasts have not been thoroughly studied. Here, through phylogenomic analyses, we reconstructed the evolutionary history of the yeast galactose utilization pathway and observed widespread and repeated losses of the ability to utilize galactose, which occurred concurrently with the losses of GALactose (GAL) utilization genes. Unexpectedly, we detected multiple galactose-utilizing lineages that were deeply embedded within clades that underwent ancient losses of galactose utilization. We show that at least two, and possibly three, lineages reacquired the GAL pathway via yeast-to-yeast horizontal gene transfer. Our results show how trait reacquisition can occur tens of millions of years after an initial loss via horizontal gene transfer from distant relatives. These findings demonstrate that the losses of complex traits and even whole pathways are not always evolutionary dead-ends, highlighting how reversals to ancestral states can occur. 相似文献
65.
Marzena Wieczorkowska Jacek Zielonka Joanna Celińska Jan Adamus Ewa Ciesielska Andrzej Marcinek 《Free radical research》2013,47(11):1157-1162
It is shown that NADH can be effectively oxidized by 1-methyl-3-nitropyridine in non-enzymatic and enzyme-mediated processes. Mechanistic issues of these reactions are discussed. These processes seem to contribute to the observed cytotoxicity of 1-methyl-3-nitropyridine. A key role of 1-methyl-3-nitropyridinyl radical formed in the enzyme-mediated processes is emphasized. 相似文献
66.
Abstract Sodium iodide was found to catalyse the phosphorylation of nucleosides by phosphorodiester derivatives such as chlorophosphates, pyrophosphates and triazolides. A similar catalytic effect, but on phosphorochloridates only, was also exerted by iodine. 相似文献
67.
Par J. Garegg Tor Regberg Jacek Stawinski Roger Strömberg 《Nucleosides, nucleotides & nucleic acids》2013,32(1-2):429-432
Abstract Oxidation of nucleoside H-phosphonate diesters has been investigated using dipyridyl disulphide, hexachloroacetone and iodine, under various reaction conditions. 相似文献
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An efficient entry to nucleoside 3′-H-phosphonoselenoate monoesters via phosphinate intermediates was developed. It involves a reaction of suitably protected nucleosides with triethylammonium phosphinate in the presence of pivaloyl chloride, followed by selenization of the intermediate nucleoside phosphinates with triphenylphosphine selenide, to produce the corresponding nucleoside H-phosphonoselenoates in 86–92% yields. 相似文献
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Abstract In this paper a short review is given of synthetic methods for the preparation of nucleoside phosphorofluoridates, nucleoside phosphorofluoridothioates and nucleoside phosphorofluoridodithioates. 相似文献
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Michal Sobkowski Jadwiga Jankowska Adam Kraszewski Jacek Stawinski 《Nucleosides, nucleotides & nucleic acids》2013,32(10-12):1469-1484
Sixteen diribonucleoside (3′-5′)-H-phosphonates were synthesized via condensation of the protected ribonucleoside 3′-H-phosphonates with nucleosides, and the influence of a nucleoside sequence on the observed stereoselectivity was analyzed. 31P NMR spectroscopy was used to evaluate a relationship between chemical shift and absolute configuration at the phosphorous center of the H-phosphonate diesters as well as of the corresponding phosphorothioate diesters. Although for the most cases such correlation was found, there was however several exceptions to the rule where the relative positions of resonances arising from R P and S P diastereomers were reversed. 相似文献