Vitamin B6 Biosynthese bei Bakterien und Pflanzen
Zusammenfassung der Projektergebnisse
The major route of vitamin B6 biosynthesis is catalyzed by PLP synthase, a protein complex containing 12 Pdx1 and 12 Pdx2 enzymes. Each Pdx1/2 pair forms an independent glutamine amidotransferase. We used x-ray crystallographic, biophysical and biochemical studies on enzymes from various sources, both pro- and eukaryotic. The study of both, enzymes from a variety of different organisms and of an inactive plant protein allowed us to gain insight into the indispensable elements of PLP biosynthesis. The structural studies derive the architectures of the complex, allow assignment of the catalytic centers and study of the enzyme tunnel required for transport of the reaction intermediate. The data allow us to understand how the Pdx1 and Pdx2 enzymes communicate to regulate each other’s activity. Deletion analysis shows that the Pdx1 C-terminus, not resolved in the crystal structures, is essential for control of catalysis. A number of reaction intermediates have been characterized in crystallographic complexes, and the studies are continued to fully resolve the complex cascade of enzymatic reactions catalyzed by this unusual oligomeric (beta alpha)8-barrel protein.
Projektbezogene Publikationen (Auswahl)
- “X-Ray Crystal Structure of Saccharomyces cerevisiae Pdx1 Provides Insights into the Oligomeric Nature of PLP Synthases”, FEBS Lett., 2009, 583, pp. 2179-2186
Neuwirth, M., Strohmeier, M., Windeisen, V., Wallner, S., Deller, S., Rippe, K., Sinning, I., Macheroux, P., Tews, I.
- “Biosynthesis of Pyridoxal phosphate“, Comprehensive Natural Products Chemistry 7, Chapter 9, T. P. Begley Editor (2010), Elsevier
Hanes, J., Ealick, S.E., Tews, I., Begley, T.P.
- “Defining the structural requirements of ribose 5-phosphate-binding and intersubunit crosstalk of the malarial pyridoxal 5-phosphate synthase”, FEBS Lett., 2010, 584, pp. 4169-4174
Derrer, B., Windeisen, V., Guédez Rodriguez, G., Seidler, J., Gengenbacher, M., Lehmann, W.D., Rippe, K., Sinning, I., Tews, I., Kappes, B.
- “PLP-dependent enzymes as potential drug targets for protozoan diseases” Biochim Biophys Acta., 2011, 1814, pp. 1567-1576
Kappes, B., Tews, I., Binter, A., Macheroux, P.
- “Pyridoxal phosphate: Biosynthesis and catabolism” Biochim Biophys Acta., 2011, 1814, pp. 1585-1596
Mukherjee, T., Hanes, J., Tews, I., Ealick, S.E., Begley, T.P.
- “Vitamin biosynthetic pathways, the PLP synthase complex, and the potential for drugging protein-protein interaction”, Drug Discovery in Infections Diseases – Apicomplexan Parasites, Chapter 13, Becker, K. Editor, (2011) Wiley-VCH, pp. 251-270
Tews, I., Sinning, I.
- “Assembly of the eukaryotic PLP-synthase complex from Plasmodium and activation of the Pdx1 enzyme”, Structure, 2012, 20, pp. 172-184
Guédez, G., Hipp, K., Windeisen, V., Derrer, B., Gengenbacher, M., Böttcher, M., Sinning, I., Kappes, B., Tews, I.
(Siehe online unter https://doi.org/10.1016/j.str.2011.11.015) - “Malarial vitamin B6 biosynthesis” Acta Cryst., 2012, A68, s32
Tews, I., Guédez, G., Windeisen, V., Sinning, I., Hipp, K., Böttcher, B., Gengenbacher, M., Derrer, B., Kappes, B.
