Octyl p-glucopyranoside

P-OG - octyl-P-glucopyranoside B - stands for h.ulk in, e.g., B850 to designate a lightharvesting BChl-protein complex B - monomeric bacteriochlorophyll /-cytochrome bj ... 

For structural studies of PrP, recombinant proteins were expressed in Escherichia coli. The constructs used contain either the intact polypeptide chain of the mature form of natural PrP (Fig. 1), possibly with some additional, construct-related residues at either chain end, or fragments thereof. Presently it appears impractical to envisage three-dimensional structure determinations with mammalian prion proteins from natural sources. However, sufficient amounts of natural PrP have been isolated to enable qualitative comparative studies with the recombinant protein by optical spectroscopy. Overall, these experiments indicate close similarity between the natural and the corresponding recombinant prion protein. Thus, the circular dichroism (CD) spectrum of monomeric hamster PrP extracted from hamster brains into a micellar environment of 30 mM w-octyl-P-glucopyranoside at pH 7.5 is typical for... 

Figure 11, Titration curves obtained from difference electronic spectra for titration of MerR with Hg(II). Titrations were performed in anaerobically sealed 1-cm path cuvettes with O.OOlAf 2-mercaptoethanol competitor. Protein was buffered at pH 7.00 with O.OlAf sodium phosphate, M NaCl, 0.1% w/v octyl-p-glucopyranoside.

Paraformaldehyde fixes by crosslinking surface proteins. Ethanol and methanol work through precipitation of membrane components. Triton X-100 and Tween-20 permeabilize membranes. Other permeabilizers are saponin (0.1-10% [v/v] in PBSG), L-lysophosphatidylcholine, and n-octyl-P-D-glucopyranoside (1-10 pg/mL in water). 

TLC and HPLC. To determine the best solvents for HPLC, 5pl of the C18 concentrated PVP fraction were separated on analytical TLC plates coated with either C18 reversed phase adsorbant or with silica. One cm sections of the plates were removed, placed in buffer, hydrolyzed, extracted and the p-damascenone charm determined. Standards containing 5 mg each of 1 -O-n-octyl- p-D-glucopyranoside and a-methyl-D-mannoside were run simultaneously on the same plate and visualized by spraying with aniline-diphenylamine-acetone-phosphoric acid 80% (4 mL 4 g 200 mL 30 mL) (10). HPLC separations were performed on a 0.46 mm x 25 cm column packed with 5 im C18, eluted with 60/40 methanol water at a flow of 0.8 mL/min. The refractive index of samples was recorded with a Knauer differential refractometer. Fractions were collected every minute and assayed for p-damascenone charm. 

Both groups used intact trimeric PS-I complex, isolated from Synechococcus using either detergent octyl P-D-glucopyranoside " or Triton XI00. Both groups obtained very similar results. We will use the results of Vassiliev et for illustration. When the intact complex ( AB ) was treated with HgCl2... 

For lipolytic enzymes—lipases and phospholipases— Braco and co-workers demonstrated that the presence of surfactants (e.g., octyl P-o-glucopyranosides) and phospholipids in the prelyophilization aqueous phase at concentrations above their critical micellar concentrations (i.e., in the form of micelles or vesicles), increased enzymatic activity by several orders of magnitude. It is believed for lipases that the formation of a small bulk aqueous interface induces an open conformation of the enzyme, where a lid that covers the active site recedes. Treatment of crude lipase with 2-propanol may also promote an open conformation of lipases. Similar to bioimprinting, the activation agent, the surfactant, must be rinsed away from the lyo-philized enzyme by anhydrous solvent prior to use. The activity enhancement decreases with increasing water content in the reaction medium. ... 

After the film is dried under vacuum to remove residual solvent, hydration is performed with 35 mM n-octyl P-D-glucopyranoside (OGP), a nonionic detergent, which is added at a concentration known to cause solubilization of the lipid components used. To ensure that this critical step is complete, the lipid mixture is heated at 50°C in a water bath. 

Patthi, S., et al. (1987). Hydrodynamic Characterization of Vasoactive Intestinal Peptide Receptor Extracted from Rat Lung Membranes in TRITON-X-100 and n-octyl-P-D-glucopyranoside, J. Biol. Chem. 262 15740-15745. 

Muramatsu W, Kawabata T (2007) Regioselective acylation of 6-O-protected octyl p-d-glucopyranosides by DMAP catalysis. Tetrahedron Lett 48 5031-5033... 

Kawabata T, Muramatsu W, Nishio T, Shibata T, Uruno Y, Stragies R (2008) Regioselective acylation of octyl p-d-glucopyranoside by chiral 4-pyrrolidinopyridine analogues. Synthesis 747-753... 

Scheme 1 Leaving group dependence in the DMAP-catalyzed acetylation of octyl p-D-glucopyranoside...

Scheme 3 Acetylation of octyl p-D-glucopyranoside using functionalized DMAP derivatives...

Scheme 4 Top selective monoacylation of octyl p-D-glucopyranoside catalyzed by C2 symmetric PPY derivative 3. Bottom monoacylated pyranosides prepared using catalyst 3...

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