His originality, moreover, goes beyond conjuring interesting lines: he invites us to partake in one soul's primary encounter with the order of things.
Once a primary encounter occurs, the following secondary encounters are independent of the free Ca2+ concentration and occur at average intervals of ∼4 ns.
As IgM antibodies are formed upon the primary encounter with antigens, their affinity is in general low before affinity maturation occurs during an isotype switch from IgM to IgG, IgA, or IgE (45, 91).
She's a formidable debater who prevailed in most of the primary encounters, except towards the end when Obama, who is still improving as a political leader, began getting the best of her.
These encounters, where the ion came to contact with a residue on the surface after diffusion in the bulk, are defined as primary encounters.
The overall ratio between secondary and primary encounters for all the protein oxygens is 0.38, which is somewhat higher than 0.3 ratio observed at the per-residue resolution.
Under physiologic conditions, were the free Ca2+ concentration is few µM, the time interval between primary encounters will be stretched to the µs time frame.
However, any attempt to adhere to the physiologic Ca2+ concentration will waste most of the simulation time waiting for primary encounters of the ion with the protein.
Thus, as at physiologic Ca2+ concentration, the primary encounters will serve as efficient donors to the nearby sites, rendering the protein's surface as a collecting antenna, and increasing the surface of the protein which is scanned by the ions.
As can be deduced from Figure 7 (middle and bottom panels), the increased binding time was due to increased primary encounters, with no change in the average dwell time (∼2.4 ns).
In the case of the WT protein, the carboxylate moiety of E60 retains the Ca2+ for ∼25% of the total accumulative time, with an average dwell time of ∼2.4 ns. Figure 7 summarizes the total binding time (panel A), primary encounters (panel B) and secondary encounters (panel C) of the side chain carboxylates of D54, D58, E60/D60 and E65 in the WT and E60D mutant (as summarized in Table S2).
