chloroplast: Photosynthetic metabolism
CO2 fixation to build up sucrose and starch (carbon assimilation)
Chloroplast: Non-photosynthetic metabolism:
• nitrogen assimilation
• sulfur assimilation
• pigment biosynthesis • lipid biosynthesis
• amino acid biosynthesis
• plant hormone biosynthesis
• vitamin E (tocopherol) biosynthesis
Nuclear genome:
codes for > 95 % of plastid proteins
How much proteine Plastome codes?
codes for about 100 proteins
The chloroplast proteome comprises about 2500 proteins
Photosynthetic protein complexes involved in linear electron transfer at the thylakoid membrane
Nuclear and plastid encoded subunits of photosynthetic complexes
Posttranslational transport mechanisms of nuclear encoded thylakoid proteins/ Cotranslational transport mechanisms of plastid encoded thylakoid proteins
Targeting pathways for nuclear encoded proteins to the thylakoid
cpSRP
chloroplast signal recognition particle
LHCPs:
light harvesting chlorophyll a/b binding proteins
• light harvesting antennas for both photosystems
• most abundant integral thylakoid membrane proteins (3 TMHs)
Insertion of LHCP into the thylakoid membrane
pathway analyzed in >100 publications of several groups
• first publication around 1985
Central questions:
structure of transit complex?
pigment loading to LHCP?
Alb3-mediated insertion?
Plastome encodes:
37 integral thylakoid membrane proteins ~ half of the subunits of photosynthetic complexes
About 50 % of the plastid-encoded TM proteins are cotranslationally inserted
Targeting of inner membrane proteins in E. coli: cotranslational / SRP-dependent
Mechanisms of cotranslational transport and insertion?Central questions:
Nascent chain processing/folding?
Protein quality control?
Sorting/docking of RNC to the insertase?
Pigment loading?
Regulation?
WHY DO WE NEED NEW ANTIBIOTICS?
MULTI-RESISTANT BACTERIA
COVID-19 - RELATED DEATHS
CHALLENGE MARKET FAILURE
Research und development
CHALLENGE INNOVATION GAP
CLASSICAL ANTIBIOTIC TARGETS
APPROACHES TO IDENTIFYING NOVEL ANTIBIOTICS
RESEARCH INTERESTS OF THE BANDOW LAB
New natural compounds
Synthetic compounds with more than one target
Investigating antibacterial targets and mechanisms
SEARCH FOR NOVEL ANTIBIOTICS FOR CLINICAL USE
RESEARCH AT THE CENTER FOR SYSTEM-BASED ANTIBIOTIC RESEARCH
ACTIVITY AND MASS-GUIDED NATURAL PRODUCT DISCOVERY
CONCLUSION AND NEXT STEP
WHY DO RIBOSOMES NEED TO BE RESCUED
trans-TRANSLATION
ALTERNATIVE RESCUE PATHWAYS IN B. subtilis
SUMMARY OMICS APPROACHES IN ANTIBIOTIC DISCOVERY
What are algae?
What are microalgae?
Commonly, ‘microalgae‘ means unicellular eukaryotes and cyanobacteria
Chloroplasts derive from cyanobacteria
Oxygenic phototrophs are the basis of life
Example: O2 as substrate and reactant in tetrapyrrole biosynthesis
The marine food chain starts with microalgae
Photosynthesis can be stressful
Vitamins and ‚biofuels‘: acclimation strategies
Microalgae are already used commercially
Photosynthesis-dependent H2 production by several species → Prof. Happe
Biotechnology book written & edited by faculty members
From the Content:
White, green, red and blue biotechnology
Traditional processes to modern technologies
(………)
Microalgae could help combat climate change
A lot of R&D is still required
Efficiency (input versus output) – for economic and environmental reasons
Photobioreactor design (e.g. energy requirements & materials, light and CO2 input, nutrient and water recycling, auomatization...)
Strain identification & optimization – by breeding or genetic engineering (natural or heterologous pathways)
The case of Chlamydomonas reinhardtii
Chlamydomonas as a model organism for basic and applied research
a eukaryotic unicellular green alga
What does it take to become a model organism?
To study an organism, you need it at hands ☺
Laboratory (preferably axenic) cultivation possible Preferably short duplication times (growth time) To study responses of an organism, you need triggers and outputs
Amenable to targeted and systemic manipulations (e.g. nutrient supply)
Amenable to extraction methods (e.g. protein, DNA, RNA, metabolites) To study gene functions, you need
Genetic information
Tools for genetic engineering
Chlamydomonas as a model
Major research fields emplyoing Chlamydomonas
Two of our research projects as examples for the values of Chlamydomonas
Old Yellow Enzymes in biotechnology and biology
H2 metabolism of Chlamydomonas
Old Yellow Enzymes: FMN-containing ene-reductases of biotechnological interest
Old Yellow Enzymes: promiscuous FMN-containing ene-reductases of biotechnological interest
Old Yellow Enzymes: not much is known about their biological role
Whole-cell biotransformation in photosynthetic (NADPH-supplying) organisms
Oxygenic photosynthesis
Photosynthetic H2 production
Bacterial cell biology: How do bacteria organize their life?
Cell growth: Monitoring pepditdoglycan synthesis
Cell motility & chemotaxis:
Major tools: Life Cell Fluorescence Microscopy & Genetics
Fluorescence Microscopy
Genetics
The complexity of bacterial popula)ons
The Myxobacteria
How to make a fruiting body?
nutrient sensing & signaling
coordination of cell motility
developmental program
Regulatory network of M. xanthus development
Coordination of cell motility
Myxobacteria use two motility system
Changing direction: Cell polarity and cell reversals
Setting the cell reversal frequency: The Frz two-component chemosensory system
"Typical" two-component chemosensory system
Setting cell reversal frequency: The Frz two-component chemosensory system
Predation
= to kill members of another species and consume their biomass
Predatory bacteria
Endobiotic predation by Bdellovibrio
Epibiotic predation by Myxococcus xanthus
What are plant-pathogen interactions?
Why do we care about plant-pathogen interactions?
Why do we STILL care about plant-pathogen interactions?
Plant-pathogen interactions are like the invasion of a fortress
How do pathogens counteract the plant defenses?
Pathogens deploy several virulence factors
How do plants defend themselves?
How do plants recognize pathogens?
PAMPs trigger basal plant defenses
Effectors from the pathogen block the plant defenses
TAL effectors
microtubule cytoskeleton
Effectors mess up with everything in the cell!
A bacterial effector
Current research projects in The Üstün Lab
Protein homeostasis: The Life and death of proteins
Protein Degradation Pathways in Eukaryotes
Ubiquitin is the “king”
Proteasome-development: Auxin
Research topics of our group grefen
PROTEIN-PROTEIN INTERACTION ASSAYS
BIMOLECULAR FLUORESCENCE COMPLEMENTATION (BIFC)
The Secretory Pathway in Plants
ER Insertion Pathways
TEXTBOOK EXAMPLE FOR TA PROTEIN INSERTION?
SRP INDEPENDENT (SND) IS PARTIALLY CONSERVED IN ARABIDOPSIS
The Arabidopsis orthologs complement the (lethal) yeast phenotype
Balancing water
Stomata: Development vs. Function
Summary
Fungal fruiting bodies: function:
production, protection and dispersal of sexual spores highly diverse morphology
What are fungi ?
Fungal phylogeny
What are the defining characteristics of fungi?
Fungal morphology: yeasts versus filamentous fungi
Filamentous fungi: multinucleate mycelial compartments
Multicellular development in eukaryotes
Evolution of multicellular development in fungi
Asexual and sexual development in fungi
Major features of Basidiomycota
Chromosome content of fungal cells and nuclei: example of a dikaryotic life cycle in a basidiomycete
Major features of Ascomycota
Chromosome content of fungal cells and nuclei: example of a haplo-dikaryotic life cycle in an ascomycete
Sexual development in filamentous ascomycetes: fruiting body formation
Genomics and transcriptomics to study multicellular development
Sordaria macrospora, Pyronema confluens and Ascodesmis nigricans
Asco- & Basidiomycota = Dikarya
with a dikaryotic stage in life cycle
Multicellular growth modes in eukaryotes
Fungal growth by simple (multicellular) structures
Fruiting bodies as complex multicellular structures
Global mushroom production in culture
Megadiversity of fruiting body shapes in Agaricomycetes
Megadiversity of basidiospore architectures
Multicellular structure formation in eukaryotes
Triggers of complex multicellular development
Actinobacteria
The bacterial cell wall
Actinobacteria: cell envelopes
Actinobacteria and biotechnology
take home
Azo dye degradation: efficient
• Lignin degradation allows applications
• Heme as dimer interface and active site
- first structural insights into a membrane protein
• Ibuprofen produced by Gordonia, by a new styrene pathway
new molecules to be discovered - even from known species.
- We are interested in antibiotics (natural and synthetic) with clinical potential that have novel targets and/or mechanisms of action.
- We use system-based approaches to identify protein targets and to gain a global view of the state of cells to build hypotheses on (dual) modes of action that can then be tested with appropriate tools.
Last changed10 months ago
