The constraints on all the 7 internal fluxes are that these fluxes are all positive. As in the previous synthetic system in the manuscript (Fig. 2), flux vectors were generated. If we want to maximize the rate of yield of E for growth on substrate A, we have to maximize the quantity z = c6v6 + c7v7 − c11b4. Applying the present method, we have obtained the pathway R1 → R2 → R3 → R7 → R9 as an o...

Rhodanese activity was demonstrated in extracts from all three taxonomic families of photosynthetic bacteria, and this activity appeared to be uncorrelated with thiosulfate metabolism.

The meromictic Lake Cadagno is characterized by a compact chemocline with high concentrations of anoxygenic phototrophic purple sulfur bacteria (PSB) and green sulfur bacteria (GSB). The co-occurrence of phylogenetically distant bacterial groups such as PSB and GSB in the same ecological niche, makes the chemocline of Lake Cadagno an ideal system for studying the conditions and consequences of ...

It is now well established that, for photosynthetic bacteria, the aerobic-to-microaerophilic transition activates the membrane-bound sensor kinase RegB, which subsequently phosphorylates the transcriptional activator RegA, thereby inducing elevated levels of intracellular photosynthetic membranes. The mechanism of RegB activation--in particular, the role of ubiquinone-10--is controversial at pr...

Aerobic photosynthetic bacteria possess the unusual characteristic of producing different classes of carotenoids. In this study, we demonstrate the presence of two distinct crt gene clusters involved in the synthesis of spirilloxanthin and canthaxanthin in a Bradyrhizobium strain. Each cluster contains the genes crtE, crtB, and crtI leading to the common precursor lycopene. We show that spirill...

We review recent theoretical and experimental advances in the elucidation of the dynamics of light harvesting in photosynthesis, focusing on recent theoretical developments in structure-based modeling of electronic excitations in photosynthetic complexes and critically examining theoretical models for excitation energy transfer. We then briefly describe two-dimensional electronic spectroscopy a...

In photosynthesis, the energy of the Sun is absorbed by the light-harvesting antenna and transferred to the reaction center (RC) within several tens of picoseconds. In the RC the solar energy is converted into electrochemical energy by means of a trans-membrane charge separation. Photosynthetic purple bacteria employ a single reaction center. In contrast, in photosynthesis of plants, algae and ...

Primer sets were designed to target specific 16S ribosomal DNA (rDNA) sequences of photosynthetic bacteria, including the green sulfur bacteria, the green nonsulfur bacteria, and the members of the Heliobacteriaceae (a gram-positive phylum). Due to the phylogenetic diversity of purple sulfur and purple nonsulfur phototrophs, the 16S rDNA gene was not an appropriate target for phylogenetic rDNA ...

Reaction centres are membrane-embedded pigment-protein complexes that transduce the energy of sunlight into a biologically useful form. The most heavily studied reaction centres are the PS-I (Photosystem I) and PS-II complexes from oxygenic phototrophs, and the reaction centre from purple photosynthetic bacteria. A great deal is known about the compositions and structures of these reaction cent...

Usually, in vivo light absorption spectra of photosynthetic bacteria are obtained by measuring cell suspensions in glass or quartz cuvettes. In such arrangements, however, the scattering of light by the suspensions as well as sedimentation or even swarming behavior of motile cells (N. Pfennig, Arch. Mikrobiol. 42:90, 1962) may give rise to various errors. The error caused by light scattering in...