6 or β-1,3 linkages of glucans12. Moreover, such a construction of the yeast cell wall results in there being many functional groups on its surface such as phosphate, carboxyl and amino groups. Under appropriate conditions of pH (above pKavalue), these...
The proton acceptor group in the recently described retinal protein, proteorhodopsin has an unusually high pKa of 7.1. It was shown that at pH above this pKa, illumination initiates a photocycle similar to that of bacteriorhodopsin, and the protein transports proton across the cell membrane. ...
the numerator in regard to the denominator in this equation, the higher the ka; the more highly dissociated the acid at equilibrium, the higher the numerator in relation to the denominator in this equation, and thus the higher the ka. given the pka of the acid and the concentrations above ...
In addition to being pH-dependent, rcrg depends on the free energy difference between the protonated (HA) and deprotonated (A−) forms of the titrable group in question. In the equations above I have used a titratable group with a neutral protonated state, but the equations are also valid...
pKa values may vary considerably depending on the temperature, ionic strength, viscosity, protein binding and other factors. Unless otherwise noted, values listed have been determined from pH-dependent fluorescence measurements at 22°C. Spectra are in aqueous buffers adjusted to >1...
Almost all known pH-responsive antibodies sense pH due to histidine residues within their variable regions. pKa value of the histidine side chain is about 6; thus, at pH below 6.0, the histidine side chain is mostly protonated, whereas, at physiologic pH 7.4, it is deprotonated. It was show...
At basic pH (above the pKa of the compound), bases have their maximum retention because they are neutral, and acids are fully ionized and have their minimum retention. For the best peak shape, retention and sample loading of basic analytes in RPLC, the mobile phase pH should be two units...
(microscopic) pKain the presence of ion binding is reduced to 8.9, nearly three units from the pKaof 11.6, calculated using configurations in the absence of sodium binding to Asp163 (Fig. 3b). Interestingly, experiment showed that the peak current increases at pH above 7 and reaches a ...
Above the cXmax threshold concentration, enough X ions start to accumulate in the pore (see the profiles of Fig. 10 of Mádai et al. [32]) to draw more Cl− ions into the pore thus steeply increasing the OFF current. Because the OFF current increases more steeply than the ON current...
Based on the above discussion, the dual response mechanism for P(NIPAAM-co-AAc)-PC was proposed. The pH response mechanism is illustrated in Fig. 5a. In the final synthesized P(NIPAAM-co-AAc), there were two reactive polymers AAc (pKa ∼ 4.25) and chitosan (pKb ∼ 6.5) [40]. ...