Distance distributions recovered from steady-state fluorescence measurements on thirteen donor-acceptor pairs with different F�rster distances

1991 ◽  
Vol 1 (4) ◽  
pp. 273-286 ◽  
Author(s):  
Wieslaw Wiczk ◽  
Peggy S. Eis ◽  
Mayer N. Fishman ◽  
Michael L. Johnson ◽  
Joseph R. Lakowicz
2004 ◽  
Vol 6 (1) ◽  
pp. 154 ◽  
Author(s):  
Olaf F. A. Larsen ◽  
Ivo H. M. van Stokkum ◽  
Frank L. de Weerd ◽  
Mikas Vengris ◽  
Charuvila T. Aravindakumar ◽  
...  

1995 ◽  
Vol 22 (2) ◽  
pp. 285 ◽  
Author(s):  
GD Price ◽  
JW Yu ◽  
SV Caemmerer ◽  
JR Evans ◽  
WS Chow ◽  
...  

Tobacco plants with reduced amounts and activities of both the chloroplast cytochrome b6/f and ATP synthase complexes have been produced using antisense RNA techniques. Antisense constructs were generated from tobacco cDNA clones coding for the Rieske FeS protein and the δ subunit of the b6/f and ATP synthase complexes respectively. Transformants with altered activities were selected using pulse-modulated fluorescence measurements. The b6/ftransformants showed high levels of steady-state fluorescence and reduced levels of both photochemical and non-photochemical quenching. In striking contrast, the ATP synthase transformants showed low levels of steady-state fluorescence and greatly increased levels of non-photochemical quenching. Transformants with a range of suppression were isolated for both constructs, in some cases with photosynthesis reduced to less than 10% of wild-type values. The most severely affected transformants showed extremely slow growth and in some cases they were unable to grow and produce seed. Progeny from the R1 seed from several cytochrome b6/f transformants have been analysed and show segregation of phenotypes ranging from intermediate to severe in repression. Intermediate and severe phenotype plants showed a reduction in Rieske FeS mRNA of more than 90% while FeS polypeptide was reduced to 60 and 86% of wild type. There was a strong correlation between photosynthesis at air and Rieske FeS polypeptide content in the antisense plants suggesting that the cytochrome b6/f complex was a major determinant of photosynthetic rate under these conditions. Photoinhibition studies of FeS antisense plants showed that there was a reduced activity of the xanthophyll cycle in the most severe plants, consistent with a reduction in the transthylakoid pH gradient and a lowered non-photochemical quenching. Preliminary studies of the ATPδ antisense plants showed that they also had reduced levels of mRNA and ATPδ polypeptide.


2007 ◽  
Vol 18 (2) ◽  
pp. 285-296 ◽  
Author(s):  
Alicia A. Williams ◽  
Sayo O. Fakayode ◽  
Onur Alptürk ◽  
Christina M. Jones ◽  
Mark Lowry ◽  
...  

Molecules ◽  
2020 ◽  
Vol 25 (3) ◽  
pp. 743
Author(s):  
Katarzyna Szymczyk ◽  
Magdalena Szaniawska ◽  
Joanna Krawczyk

Density, viscosity and surface tension of Kolliphor® ELP, the nonionic surfactant aqueous solutions were measured at temperature T = 293–318 K and at 5K interval. Steady-state fluorescence measurements have been also made using pyrene as a probe. On the basis of the obtained results, a number of thermodynamic, thermo-acoustic and anharmonic parameters of the studied surfactant have been evaluated and interpreted in terms of structural effects and solute–solvent interactions. The results suggest that the molecules of studied surfactant at concentrations higher than the critical micelle concentration act as structure makers of the water structure.


1993 ◽  
Vol 47 (3) ◽  
pp. 277-282 ◽  
Author(s):  
A. Yvette Will ◽  
Arsenio Muñoz De La Peña ◽  
Thilivhali T. Ndou ◽  
Isiah M. Warner

The influence of amines on the aqueous beta-cyclodextrin ( β-CD): pyrene complex with the use of steady-state fluorescence measurements is examined. A 2:1 β-CD:pyrene complex is reported in the presence of either tert-butylamine (TBA) or n-propylamine (PA). At low amine concentrations, the role of the amine is to shield pyrene from the bulk aqueous phase. However, at higher TBA concentrations, there exists a competitive equilibrium between the amine and pyrene for the β-CD cavity. The formation constants for the various complexes in the presence of either amine were estimated to be of comparable order of magnitude.


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