Post-genomic characterization of metabolic pathways in Sulfolobus solfataricus

摘要: The physiological functions and mode of actions different biomolecules are continuous interest a prerequisite to fully understand appreciate the potential Archaea their molecules. We chose study Sulfolobus solfataricus for its stable (heat-resistant) enzymes specific metabolic potential, ease cultivation this organism, relative large amount knowledge about heat-loving acidophilic organism. selected systems approach behaviour organism trying make steps forward into unknown, whenever possible link exploration exploitation. S.solfataricus is an essential element in all approaches that genotype phenotype. Hence, attention given advanced culturing extremophile have been used experimental studies described here ( Chapters 3-6 ). Systems analysis includes integration available omics data increasingly 3 4 However, most has archaeal transcriptome hence important literature on summarized Chapter 2 In chapters ) various applied gain understanding pathways Sulfolobus. describes central carbon pathways, consisting (non-) phosphorilated Entner-Douderoff (ED) pathway citric acid cycle. Different functional genomic were model response growth sources, D-Glucose vs. Tryptone Yeast Extract. complete was studied using PCR-based microarrays. addition proteome 2D-electrophoresis map combination with 13 N- labelling technique determine protein fluctuations. Despite difference medium, very few significant differences or RNA level observed two conditions. Therefore regulation these does probability not occur through changes abundance but presumably rather by direct enzyme activity. This unlike thermophilic Euryarchaea: Thermococcus kodaaraensis (Kanai, Akerboom et al. 2007)and Pyrococcus furiosus (Schut, Brehm 2003)where extensive glycolytic genes similar situation. degradation D-arabinose as chapter 3. S. grown either D-glucose comprehensive carried out. result only elucidation route, also general prokaryotic pentose, hexaric acids hydroxyproline which supports theory genesis recruitment. Also predicted cis-regulatory induce arabinose degrading when needed. involved proposed cloned, expressed function biochemically measured. showed enzymes, can be degraded 2-oxogluterate, one metabolites part 5 reports effects oxygen concentrations solfataricus. controlled relatively easily bioreactor, crucial rapid reproducible growth. Based experiments microcosms, types could seen. At 35% (v/v gas phase) cultures did grow, indicating solfa-taricus experiences lethal dose oxygen. 26-32% impaired, suggesting moderate toxicity compared reference (21%). ranges 16-24% oxygen, standard observed, comfortable ranges. For lower amounts (1.5-15%), comparable reference, respiratoryefficiency increased. To get some more insight behaviour, we looked at transcriptome. It differential expression several genes, including encoding terminal oxidases, adapts adapting respiratory machinery.  6 zeaxanthin species. Zeaxanthin colorant vital importance human eye. responsible production presented. this, DNA microarrays, bioinformatics well molecular genetics techniques used. A crtx-like gene operational known species able attach sugar-like molecules zeaxanthin, improves solubility water, many food uses. cloned solfataricus, shibatae, acidocaldarius overproducing E. coli strain. demonstrated products shibatae attaching zeaxanthin. ctrx-like operating coli. probably due fact truncated. further improved carotenoid it shown modify although each produces modifications.