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Aquatic Plants Native to America
Published in Namrita Lall, Aquatic Plants, 2020
Bianca D. Fibrich, Jacqueline Maphutha, Carel B. Oosthuizen, Danielle Twilley, Khan-Van Ho, Chung-Ho Lin, Leszek P. Vincent, T. N. Shilpa, N. P. Deepika, B. Duraiswamy, S. P. Dhanabal, Suresh M. Kumar, Namrita Lall
According to the NCBI database, about 203 genes have been sequenced including clone marker sequences, chloroplast atpB gene, internal transcribed spacer partial sequences, RNA polymerase C genes, ribulose-1,5-bisphosphate carboxylase/oxygenase genes, MatK genes, ATP synthase genes, cytochrome b6 (petB) genes. (Accession: HQ181413.1) and photosystem I subunits. A summary of the genes is provided in Table 4.14.
Crystallizing Membrane Proteins: Experiments on Different Systems
Published in Hartmut Michel, Crystallization of Membrane Proteins, 1991
As in plants, cyanobacteria have two photosystems in their photosynthetic apparatus: photosystem II which is involved in oxygen evolution and H+ pumping and photosystem I which provides reducing equivalents for the production of NADPH.42 Intact and active photosystem I reaction center (PS1-rc) complexes can be easily isolated from a number of cyanobacteria. From the thermophilic cyanobacterium Phormidium laminosum, we have isolated a 450 kDa complex which is stable in a number of detergents including SDS10. The PS1-rc is an extremely heterogeneous complex consisting of at least four distinct polypeptides, iron-suffer centers, and about 60 light-harvesting pigment molecules. The proper choice of detergent is very important here as we wish to keep this complex intact. Some small detergent like β-OG are inadequate for this task and result in pigment loss. Instead, the PS1-rc complex was generally handled in Triton X-100 or dodecyl maltoside (C12-M).
The Reactivity Of Copper Sites In The “Blue” Copper Proteins
Published in René Lontie, Copper Proteins and Copper Enzymes, 1984
These are the best characterized among the single blue copper proteins. Their Mr values are ≈10,000 (Appendix 1) and the amino-acid sequences of a very large number of Pc’s have been determined and show a remarkably high degree of conservation.17 The great similarity of PMR spectra of Pc(I) from a variety of higher plants18 led to the suggestion that the structure of poplar Pc referred to in Section I is maintained by this whole group. They function as electron carriers in all higher plants, in many green algae, and some blue-green ones. The site of their action is commonly believed to be located between the membrane-bound cytochrome f and the Ρ-700 chlorophyll pigment of photosystem I. The redox potential of Pc at pH 7 is ≈370 mV.5 This value is between those of Cyt f and Ρ-700, in agreement with the position of Pc in the electron-transfer chain. The orientation of Pc on the thylakoid membrane is still a matter of controversy. It is not clear whether it is bound to the inner or outer thylakoid surface. Cyt f and Ρ-700 are probably located close to the interior thylakoid surface, whereas Pc is apparently bound loosely to the membrane as it can be solubilized readily.
Characterization of planktonic and biofilm cells from two filamentous cyanobacteria using a shotgun proteomic approach
Published in Biofouling, 2020
Maria João Leal Romeu, Dany Domínguez-Pérez, Daniela Almeida, João Morais, Alexandre Campos, Vítor Vasconcelos, Filipe J. M. Mergulhão
Proteins related to photosystems I and II and with allophycocyanin were found in three of the four biofilm condition groups (Table 1 in dark grey shading). The specific conditions in which these proteins were identified can be found in the Supplementary material, SM5. Photosystem I (PS I, plastocyaninferredoxin oxidoreductase) and photosystem II (PS II, waterplastoquinone oxidoreductase) are multisubunit protein complexes located in the thylakoid membranes of cyanobacteria, algae and higher plants (Nelson and Yocum 2006). Although in the present study the PsaF protein was only identified in biofilms of both the cyanobacterial strains formed at 40 s−1 (Table 1), this protein is also related to photosystems (Photosystem I subunit III). A study performed by Huang et al. (2002) also identified proteins related to photosystems in the plasma membrane of Synechocystis PCC 6803. A proteomic study with different strains of M. aeruginosa showed that the majority of proteins shared among all strains were involved in photosynthesis and respiration (Alexova et al. 2011). Thus, the distribution of protein identification obtained in the present study is typical for cyanobacteria.
Current knowledge about the impact of microgravity on the proteome
Published in Expert Review of Proteomics, 2019
Sebastian M. Strauch, Daniela Grimm, Thomas J. Corydon, Marcus Krüger, Johann Bauer, Michael Lebert, Petra Wise, Manfred Infanger, Peter Richter
Chen and Wang analyzed 17-day-old rice seedlings grown on Shenzhou-8 with special attention on the proteins involved in photosynthesis [58]. Compared to the ground control, from 454 differently expressed proteins identified, 38 were related to photosynthesis: 34 were downregulated, 4 were upregulated. However, the in-flight 1g control was lost and could not be compared to the µg experiment. Photosystem I (PSI) activity was more diminished than photosystem II (PSII) activity, as measured by fluorescence. This is remarkable, as under normal conditions on Earth, PSII is more sensitive to environmental factors. The results were in agreement with similar studies on the Space Shuttle [59] and RPMs [60]. Ten proteins involved in antioxidant defense in chloroplasts were upregulated, while four were downregulated.
An outlook on using serial femtosecond crystallography in drug discovery
Published in Expert Opinion on Drug Discovery, 2019
Alexey Mishin, Anastasiia Gusach, Aleksandra Luginina, Egor Marin, Valentin Borshchevskiy, Vadim Cherezov
The first and still one of the most successful injectors to date, a gas dynamic virtual nozzle (GDVN), was introduced in 2008 [39]. A simple and robust construction of two coaxial capillaries produces a stream of crystals flowing in their liquid crystallization medium focused to a diameter of only few micrometers by a sheath of gas. GDVN was successfully used for the first SFX demonstration with microcrystals of photosystem I [38] and many other SFX experiments, however, its major drawback of a high sample consumption (flow rates above 10 µl/min) prompted the development of modified and alternative injectors. For example, one such modification, a double flow focusing nozzle (DFFN), allowed for sample reduction by up to eight times [40].