Hydrolysis versus Phosphorolysis of Glycans

their preference for a- or P-conflguration at the scissile C-1 linkage of glycans and 

The hydrolytic degradation of nucleic acids is catalyzed by nucleases, which are phosphodiesterases because they cleave the phosphodiesteric bonds hydrolytically (Linn et al., 1993). The cleavage can potentially occur on either side of the phosphorus atom, i.e. on the 3 -side (a) and the 5 -side (b)  

Hydrolysis on the a-side leaves the phosphate attached to the 5 position of the adjacent nucleotide, whereas the b- side cleavage yields 3 -phosphate. The enzymes that hydrolyze the internal linkages are known as endonucleases and those that remove the terminal nucleotides are called exonucleases (Table 12.9). 

In addition to common nucleases listed in Table 12.9, cells contain many distinct nucleases, which perform essential functions (Deutscher, 1993). For example, RNases are involved in  

The restriction nucleolysis of DNA by restriction endonucleases (restriction enzymes), which recognizes specific sequences on the target DNA will be described in the Chapter 13. 

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