Other Nucleic Acid Modifications

Other non-protein molecules, such as nucleic acids and oligonucleotides, may not normally possess primary amines of sufficient nucleophilicity to react with common modification reagents. The ability to add amine functionalities to these molecules is sometimes the only route to successful conjugation. Creating amines at specific sites within these molecules allows for site-directed modification at known positions, thus better assuring active conjugates once formed. 

Another popular tag for use with immunoglobulins is biotin. Modification reagents that can add a functional biotin group to proteins, nucleic acids, and other molecules now come in many shapes and reactivities (Chapter 11). Depending on the reactive group present on the biotinylation... 

Since a knowledge of the correct tautomeric form of the pyrimidines is a requisite for understanding the mode of binding to active sites, as well as nucleic acid structure and modification, the formulae of the conventionally-named 2- and 4-hydroxypyrimidines are presented in the correct lactam, or pyrimidone, form in this chapter. Other physical properties of the pyrimidines, such as dissociation constants, protonation sites, and distribution coefficients, are presented in cases where there is a known relation to drug activity. Biogenesis and enzyme control mechanisms are discussed where they relate to an understanding of inhibitor action. 

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