Ensuring substrate retention. Part

One of the best ways to ensure retention of activity in protein molecules is to avoid doing chemistry at the active center. The active center is that portion of the protein where ligand, antigen, or substrate binding occurs. In simpler terms, the active center (or active site) is that part that has specific interaction with another substance (Means and Feeney, 1971). For the preparation of enzyme derivatives, it is important to protect the site of catalysis where conversion of substrate to product happens. For instance, when working with antibody molecules, it is crucial to stay away from the two antigen binding sites. 

Chemical mass transfer responsible for partitioning of contaminants constitutes a significant part of the processes involved in the transport and fate of contaminants. In the longer term, the redox environment (pE) and subsequent reduction-oxidation reactions will ultimately determine the final fate of the contaminants. The assessment of whether retention or retardation processes are responsible for the observed partitioning and hence the attenuation of contaminants within the soil matrix, is vital and critical in the evaluation of the natural attenuation capability of the soil barrier system. The dilemma facing both regulatory agencies and practitioners is obvious If potential pollution hazards and threats to public health and the environment are to be minimized or avoided, How can one ensure that the processes for contaminant attenuation in the substrate are the result of (irreversible sorption) retention... 

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