160776-83-0Relevant academic research and scientific papers
Invisible detergents for structure determination of membrane proteins by small-angle neutron scattering
Midtgaard, S?ren Roi,Darwish, Tamim A.,Pedersen, Martin Cramer,Huda, Pie,Larsen, Andreas Haahr,Jensen, Grethe Vestergaard,Kynde, S?ren Andreas R?ssell,Skar-Gislinge, Nicholas,Nielsen, Agnieszka Janina Zygadlo,Olesen, Claus,Blaise, Mickael,Dorosz, Jerzy Józef,Thorsen, Thor Seneca,Venskutonyt?, Raminta,Krintel, Christian,M?ller, Jesper V.,Frielinghaus, Henrich,Gilbert, Elliot Paul,Martel, Anne,Kastrup, Jette Sandholm,Jensen, Poul Erik,Nissen, Poul,Arleth, Lise
, p. 357 - 371 (2018/01/04)
A novel and generally applicable method for determining structures of membrane proteins in solution via small-angle neutron scattering (SANS) is presented. Common detergents for solubilizing membrane proteins were synthesized in isotope-substituted versions for utilizing the intrinsic neutron scattering length difference between hydrogen and deuterium. Individual hydrogen/deuterium levels of the detergent head and tail groups were achieved such that the formed micelles became effectively invisible in heavy water (D2O) when investigated by neutrons. This way, only the signal from the membrane protein remained in the SANS data. We demonstrate that the method is not only generally applicable on five very different membrane proteins but also reveals subtle structural details about the sarco/endoplasmatic reticulum Ca2+ ATPase (SERCA). In all, the synthesis of isotope-substituted detergents makes solution structure determination of membrane proteins by SANS and subsequent data analysis available to nonspecialists.
2H NMR Evidence for dynamic disorder in human skin induced by the penetration enhancer Azone
Bezema,Marttin,Roemele,Brussee,Bodde,De Groot
, p. 785 - 791 (2007/10/03)
Penetration enhancers mediate trans-dermal drug delivery. The penetration enhancer dodecyl-azacycloheptanone (Azone) was characterized in situ with 2H NMR on human stratum corneum treated with either uniformly deuterated Azone or penetration enhancer with only the entire chain deuterated, in both cases in propylene glycol. The 2H NMR spectrum at ambient temperature constitutes a single narrow line only 180 Hz wide. This contrasts with the complex lineshapes 1-25 kHz wide commonly observed for methylene deuterons of lipids in a bilayer gel phase. Hence there is no evidence for differences in orientational behaviour between different deuterons at ambient temperature. The narrow line translates into a low overall order parameter SCD c 6 × 10-6 s, in all possible directions. At temperatures of about 150 K a 2H NMR pattern characteristic for a random isotropic powder was observed on samples of stacked stratum corneum sheets at different orientations with respect to the magnetic field. This provides strong evidence for random isotropic freezing of the Azone molecules upon cooling. The 2H NMR data suggest than incubation with Azone in propylene glycol provokes dynamic structural disorder of the intercellular lamellar lipid structure throughout the stratum corneum and possibly even the creation of fluid domains involving the intercellular lipids, which may be essential for the penetration enhancing effect.
