Month Flat Week Day
Date: Monday, March 16, 2015 15:00 - 16:00
Categories: Seminar
Department of Chemistry
Seminar

Speaker:
Jörg Nickelsen
Biozentrum der LMU München, AG Molekulare Pflanzenwissenschaften, Botanik, Munich Germany

Title:
Biogenesis and Biomedical Utilization of the Photosynthetic Apparatus

Host: Christiane Funk

Room: KB3A9, Lilla hörsalen KBC

Abstract:
Cyanobacteria, algae and plants can convert light energy to chemical energy using a very similar type of photosynthetic membrane system, named thylakoids. Current molecular analyses suggest that the initial steps of the biogenesis of the cyanobacterial energy conversion system, in particular photosystem (PS) II, progress in a membrane subfraction representing a biosynthetic center which is marked by the PS II assembly factor PratA. This factor binds and delivers manganese (Mn) to PS II and, consequently, is involved in the assembly of its oxygen evolving Mn4CaO5 cluster.
Also in chloroplasts of the eukaryotic alga Chlamydomonas reinhardtii, PSII biogenesis centres – so called translation (T) zones – have been described. We have recently identified the DLA2 factor which appears to target the chloroplast psbA mRNA to these T-zones. Interestingly, DLA2 represents the E2 subunit of the plastid pyruvate dehydrogenase enzyme suggesting a crosstalk between gene expression and carbon metabolism via this protein.
In an applied approach, the oxygen evolving activity of PSII is used to provide a constant source of oxygen supply to engineered mammalian skin tissues which usually suffer from hypoxia due to poor vascularization. In particular, our data suggest that bioartificial scaffolds can be loaded with the microalgae Chlamydomonas reinhardtii, showing high biocompatibility and photosynthetic activity in vitro. The results of this study represent a first step towards the establishment of engineered autotrophic tissues and suggest that the use of photosynthetic cells can overcome a broader spectrum of hypoxic stress conditions.