Matches in SemOpenAlex for { <https://semopenalex.org/work/W1828575624> ?p ?o ?g. }
- W1828575624 abstract "The conversion of deoxyuridine 5'-monophosphate (dUMP) to deoxythymidine 5'-monophosphate (dTMP) by thymidylate synthases is one key step in the biosynthesis of pyrimidine deoxyribonucleotides. Two non homologous families of thymidylate synthases exist in the prokaryotic world (bacteria and archaea): ThyA and ThyX. The almost exclusive phylogenetic distribution of both enzyme families is complex and does not follow organismal phylogenetic relations. Proteins of both families do not share sequence or structural similarities, and the catalytic mechanisms and efficiencies are different. The work presented in this thesis demonstrates that ThyX activity is essential for the survival of the bacterium Rhodobacter capsulatus in absence of exogenous thymidine. Based upon the results of genetic complementation assays and a mathematical model of the folate metabolism, we showed that a very low dihydrofolate reductase activity is enough to allow survival of thyX containing organisms. Moreover, using a genetic approach and statistical analysis of more than 400 prokaryotic genomes, I was able to show that organisms using thymidylate synthase ThyX have slow DNA replication and growth rates, and mostly possess a small genome. Based upon these findings, I propose a model in which the weak activity of thymidylate synthases ThyX is limiting DNA replication and consequently genome expansion. Finally, I studied the pyrimidine metabolism in the human pathogenic bacterium Helicobacter pylori. In particular, I demonstrated that this bacterium is sensible to the anticancer drug ! 5-fluorouracil (5-FU) despite the absence of a uracil salvage pathway. I showed that the H. pylori orotate phosphoribosyltransferase is able to complement the uracil auxotrophy of an Escherichia coli strain, indicating that this enzyme could be responsible for the 5-FU sensitivity of H. pylori. The studies presented in this thesis allow a better understanding of the physiological consequences of the use of thymidylate synthase ThyX and provide an explanation for the apparent sporadic distribution of both thymidylate synthase families in the prokaryotic world." @default.
- W1828575624 created "2016-06-24" @default.
- W1828575624 creator A5014596588 @default.
- W1828575624 date "2008-05-26" @default.
- W1828575624 modified "2023-09-22" @default.
- W1828575624 title "Physiological consequences of thymidylate synthase ThyX utilization." @default.
- W1828575624 cites W104710838 @default.
- W1828575624 cites W117830047 @default.
- W1828575624 cites W1480861155 @default.
- W1828575624 cites W1493392084 @default.
- W1828575624 cites W1508421499 @default.
- W1828575624 cites W1512950464 @default.
- W1828575624 cites W1528787450 @default.
- W1828575624 cites W1539927167 @default.
- W1828575624 cites W1554765608 @default.
- W1828575624 cites W1556969260 @default.
- W1828575624 cites W1566887656 @default.
- W1828575624 cites W1572643844 @default.
- W1828575624 cites W1575542444 @default.
- W1828575624 cites W1578197836 @default.
- W1828575624 cites W1579095159 @default.
- W1828575624 cites W1600869797 @default.
- W1828575624 cites W1627863859 @default.
- W1828575624 cites W1662124894 @default.
- W1828575624 cites W1800076290 @default.
- W1828575624 cites W1880629566 @default.
- W1828575624 cites W1955621549 @default.
- W1828575624 cites W1966501953 @default.
- W1828575624 cites W1967164846 @default.
- W1828575624 cites W1967465227 @default.
- W1828575624 cites W1968989163 @default.
- W1828575624 cites W1969655354 @default.
- W1828575624 cites W1971359499 @default.
- W1828575624 cites W1971403296 @default.
- W1828575624 cites W1972010400 @default.
- W1828575624 cites W1974358242 @default.
- W1828575624 cites W1976964059 @default.
- W1828575624 cites W1978102882 @default.
- W1828575624 cites W1978796203 @default.
- W1828575624 cites W1980182582 @default.
- W1828575624 cites W1980253503 @default.
- W1828575624 cites W1980335188 @default.
- W1828575624 cites W1982444105 @default.
- W1828575624 cites W1987355768 @default.
- W1828575624 cites W1988037647 @default.
- W1828575624 cites W1988969077 @default.
- W1828575624 cites W1989756084 @default.
- W1828575624 cites W1990453950 @default.
- W1828575624 cites W1990567986 @default.
- W1828575624 cites W1991571104 @default.
- W1828575624 cites W1993095565 @default.
- W1828575624 cites W1994277771 @default.
- W1828575624 cites W1995136541 @default.
- W1828575624 cites W1998228463 @default.
- W1828575624 cites W2003972640 @default.
- W1828575624 cites W2005217453 @default.
- W1828575624 cites W2005635464 @default.
- W1828575624 cites W2006884754 @default.
- W1828575624 cites W2008272663 @default.
- W1828575624 cites W2009598543 @default.
- W1828575624 cites W2011107379 @default.
- W1828575624 cites W2011295602 @default.
- W1828575624 cites W2011847166 @default.
- W1828575624 cites W2012690739 @default.
- W1828575624 cites W2013532519 @default.
- W1828575624 cites W2014560396 @default.
- W1828575624 cites W2016588572 @default.
- W1828575624 cites W2017678973 @default.
- W1828575624 cites W2019181444 @default.
- W1828575624 cites W2022162825 @default.
- W1828575624 cites W2022507235 @default.
- W1828575624 cites W2022838525 @default.
- W1828575624 cites W2023766026 @default.
- W1828575624 cites W2027229485 @default.
- W1828575624 cites W2028027718 @default.
- W1828575624 cites W2028361507 @default.
- W1828575624 cites W2030564603 @default.
- W1828575624 cites W2031386057 @default.
- W1828575624 cites W2032559209 @default.
- W1828575624 cites W2032619610 @default.
- W1828575624 cites W2034720620 @default.
- W1828575624 cites W2035520652 @default.
- W1828575624 cites W2036408983 @default.
- W1828575624 cites W2037984857 @default.
- W1828575624 cites W2039902861 @default.
- W1828575624 cites W2040941311 @default.
- W1828575624 cites W2046200816 @default.
- W1828575624 cites W2047421740 @default.
- W1828575624 cites W2050218740 @default.
- W1828575624 cites W2053080660 @default.
- W1828575624 cites W2054896894 @default.
- W1828575624 cites W2054985667 @default.
- W1828575624 cites W2055016234 @default.
- W1828575624 cites W2055864549 @default.
- W1828575624 cites W2058968448 @default.
- W1828575624 cites W2059849208 @default.
- W1828575624 cites W2063633070 @default.
- W1828575624 cites W2066266675 @default.
- W1828575624 cites W2066299584 @default.
- W1828575624 cites W2066334469 @default.