Biosynthetic Oligonucleotide Libraries

Biosynthetic polypeptide libraries are the translation of a genetic, oUgonucleotide-based diversity information into a biologically relevant pool of p)otential binders, catalysts, or receptors. The previous section illustrated how the availability of complex DNA sequences and of the appropriate techniques for their synthesis and manipulation allows the biological production of diverse polypeptide libraries. However, the intrinsic properties of nucleotide sequences have themselves stimulated researchers into budding a variety of oligonucleotide (ON) libraries per se for a variety of applications. 

The first part of this section is devoted to the description of the in vitro selection process, which enables the iterative selection/ampUfication cycles to reliably and accurately furnish ON sequences. 

The state of the art in the SPS of oligonucleotides (see Section 2.2) has reached excellent levels of rehabihty and performance, which can be summarized as follows  

Sequences of 100 oligomers can be routinely synthesized with extremely high purity and yield. 

Libraries of up to 10 individuals can be made and handled using various techniques. 

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BIOSYNTHETIC OLIGONUCLEOTIDE LIBRARIES 531 10.2.2 In Vitro Selection of ON Sequences... 

Oligonucleotide libraries are commonly used either to encode biosynthetic display peptide libraries (Section 11.1) or to screen for novel nucleotide ligands (aptamer) or catalytic activities (ribozymes). They are produced using high-quality automated ON SP protocols seen in Section 2.2, but their amplification and selection are performed via biological protocols (see Sections 4.2.4 and 11.2). 

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