Solid-State NMR Spectroscopic Study of Phosphate Sorption Mechanisms on Aluminum (Hydr)oxides

2013 ◽  
pp. 130725144353009 ◽  
Author(s):  
Wei Li ◽  
Xionghan Feng ◽  
Yupeng Yan ◽  
Donald L. Sparks ◽  
Brian L. Phillips
2012 ◽  
Vol 5 (3) ◽  
pp. 698-715 ◽  
Author(s):  
Chen Song ◽  
Lars-Oliver Essen ◽  
Wolfgang Gärtner ◽  
Jon Hughes ◽  
Jörg Matysik

2015 ◽  
Vol 17 (4) ◽  
pp. 2540-2549 ◽  
Author(s):  
Zhongjie Lin ◽  
Julian R. Jones ◽  
John V. Hanna ◽  
Mark E. Smith

Multinuclear solid state NMR, especially 17O, shows the structural evolution of calcium silicate sol–gel bioactive glasses during stabilisation and subsequent reaction with simulated body fluid.


2019 ◽  
Vol 20 (15) ◽  
pp. 3656 ◽  
Author(s):  
Qian-Zhao Xu ◽  
Pavlo Bielytskyi ◽  
James Otis ◽  
Christina Lang ◽  
Jon Hughes ◽  
...  

Unlike canonical phytochromes, the GAF domain of cyanobacteriochromes (CBCRs) can bind bilins autonomously and is sufficient for functional photocycles. Despite the astonishing spectral diversity of CBCRs, the GAF1 domain of the three-GAF-domain photoreceptor all2699 from the cyanobacterium Nostoc 7120 is the only CBCR-GAF known that converts from a red-absorbing (Pr) dark state to a far-red-absorbing (Pfr) photoproduct, analogous to the more conservative phytochromes. Here we report a solid-state NMR spectroscopic study of all2699g1 in its Pr state. Conclusive NMR evidence unveils a particular stereochemical heterogeneity at the tetrahedral C31 atom, whereas the crystal structure shows exclusively the R-stereochemistry at this chiral center. Additional NMR experiments were performed on a construct comprising the GAF1 and GAF2 domains of all2699, showing a greater precision in the chromophore–protein interactions in the GAF1-2 construct. A 3D Pr structural model of the all2699g1-2 construct predicts a tongue-like region extending from the GAF2 domain (akin to canonical phytochromes) in the direction of the chromophore, shielding it from the solvent. In addition, this stabilizing element allows exclusively the R-stereochemistry for the chromophore-protein linkage. Site-directed mutagenesis performed on three conserved motifs in the hairpin-like tip confirms the interaction of the tongue region with the GAF1-bound chromophore.


ChemInform ◽  
2014 ◽  
Vol 45 (32) ◽  
pp. no-no
Author(s):  
Christoph Hoeting ◽  
Hellmut Eckert ◽  
Frank Haarmann ◽  
Rainer Poettgen

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