Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
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Sugar metabolism: from enzyme cascades towards physiology and application
S. solfataricus and S. acidocaldarius are among the best studied archaeal species up to date. Their central carbohydrate metabolism (CCM) has been clarified in some detail, however, leaving some open questions in respect to pathways of different carbon sources and their regulatory mechanisms. In this research, some of these open questions have been addressed, thus enhanced our understanding of the CCM in Archaea. In chapter 3.1, the putative pyruvate kinase and phosphoenolpyruvate synthetase (PEPS) from S. solfataricus catalyzing the carbon switch between PEP and pyruvate were recombinantly expressed, purified and characterized, indicating the corresponding annotated functions. In addition, it was indicated by effectors testing that the Sso-PK was allosterically inhibited by ATP and isocitrate, and the Sso-PEPS was inhibited by AMP and α-ketoglutarate, suggesting that in this carbon switch, glycolysis was inhibited under high energy charge (high concentration of ATP) and accumulation of building blocks in the TCA cycle (isocitrate), while gluconeogenesis was reduced under low cell energy charge (high concentration of AMP) and ammonium limitation. In chapter 3.2, pentose transport and pentose degradation pathways in S. acidocaldarius were intensively studied including transcriptomic analyses, enzyme activity assays in cell-free extract, protein expression, purification and characterization, as well as construction of gene deletion mutants and growth studies. The results revealed an ATP-binding cassette (ABC) transporter for pentose uptake and demonstrated that D-xylose as well as L-arabinose were mainly/exclusively degraded via the Weimberg pathway, while the Dahms pathway was dispensable in S. acidocaldarius MW001. In chapter 3.3, a pathway for L-fucose degradation in S. solfataricus was proposed based on the integrated systems biology approach. The activity of the responsible enzymes in cell-free extract of the L-fucose grown cells was demonstrated, and the involved proteins were recombinantly expressed, ...
Sugar metabolism: from enzyme cascades towards physiology and application
S. solfataricus and S. acidocaldarius are among the best studied archaeal species up to date. Their central carbohydrate metabolism (CCM) has been clarified in some detail, however, leaving some open questions in respect to pathways of different carbon sources and their regulatory mechanisms. In this research, some of these open questions have been addressed, thus enhanced our understanding of the CCM in Archaea. In chapter 3.1, the putative pyruvate kinase and phosphoenolpyruvate synthetase (PEPS) from S. solfataricus catalyzing the carbon switch between PEP and pyruvate were recombinantly expressed, purified and characterized, indicating the corresponding annotated functions. In addition, it was indicated by effectors testing that the Sso-PK was allosterically inhibited by ATP and isocitrate, and the Sso-PEPS was inhibited by AMP and α-ketoglutarate, suggesting that in this carbon switch, glycolysis was inhibited under high energy charge (high concentration of ATP) and accumulation of building blocks in the TCA cycle (isocitrate), while gluconeogenesis was reduced under low cell energy charge (high concentration of AMP) and ammonium limitation. In chapter 3.2, pentose transport and pentose degradation pathways in S. acidocaldarius were intensively studied including transcriptomic analyses, enzyme activity assays in cell-free extract, protein expression, purification and characterization, as well as construction of gene deletion mutants and growth studies. The results revealed an ATP-binding cassette (ABC) transporter for pentose uptake and demonstrated that D-xylose as well as L-arabinose were mainly/exclusively degraded via the Weimberg pathway, while the Dahms pathway was dispensable in S. acidocaldarius MW001. In chapter 3.3, a pathway for L-fucose degradation in S. solfataricus was proposed based on the integrated systems biology approach. The activity of the responsible enzymes in cell-free extract of the L-fucose grown cells was demonstrated, and the involved proteins were recombinantly expressed, ...
Sugar metabolism: from enzyme cascades towards physiology and application
Shen, Lu (Autor:in) / Siebers, Bettina
27.10.2020
Hochschulschrift
Elektronische Ressource
Englisch
| NTIS | 1967
Investigation of cavitating cascades
| Engineering Index Backfile | 1966