Site-directed manipulation

Synthetic oligonucleotides are very important tools in the study and manipulation of DNA, including such techniques as site-directed mutagenesis and DNA amplification by the polymerase chain reaction. The techniques for chemical synthesis of oligonucleotides are highly developed. Very efficient automated methodologies based on solid phase synthesis are used extensively in fields that depend on the availability of defined DNA sequences.52... 

The time is ripe for the widespread application of biocatalysis in industrial organic synthesis and according to a recent estimate [113] more than 130 processes have been commercialised. Advances in recombinant DNA techniques have made it, in principle, possible to produce virtually any enzyme for a commercially acceptable price. Advances in protein engineering have made it possible, using techniques such as site directed mutagenesis and in vitro evolution, to manipulate enzymes such that they exhibit the desired substrate specificity, activity, stability, pH profile, etc. [114]. Furthermore, the development of effective immobilisation techniques has paved the way for optimising the performance and recovery and recycling of enzymes. 

The A -Fmoc protection is the essential feature of the Fmoc/tBu strategy of SPPS, but the stability/deprotection characteristics of this group (see Section 2.1.1.1.1.3) can be conveniently exploited in the context of the Boc/Bzl protection scheme for site-directed chemical manipulations at co-amino functions on resin and in solution. 

---