Bound breakage mechanism

In both mechanisms, nitrite binding involves the displacement of H2O to form a Cu -NO complex. The water departs as OH leaving the Asp residue protonated. Reduction of the type 2 center then results in the breakage of the O— N bond of nitrite proximal to the Asp residue, which protonates the cleaved oxygen to form OH . The enzyme at this stage has a type 2 center with NO bound, Cu -NO (or Cu"-NO ). 

Proposed mechanism of GM-CSF release from PG-MP. GM-CSF adsorption comprises both reversibly bound and irreversibly bound adsorbate clusters. Reversible adsorption (GM-CSF release) is initially mediated by breakage of weaker hydrogen bonding, electrostatic and hydrophobic interactions. Flowever, after an initial release phase, a predominance of irreversibly bound adsorbate clusters remain. Over time, the degradation (by hydrolysis) of PG-MP releases anchored peptides until desorption becomes energetically favorable. Thus, the latter release profile may be attributed to a degradation-controlled mechanism of desorption. 

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