Annealing is a bimolecular process, but there are competing processes in which both intrastrand and interstand base pairs can form, ultimately leading to the stable duplex. Cleavage of DNA and RNA Polymers Chemical Stability RNA is susceptible to alkaline hydrolysis because of the presence of the free 2 ' -OH on ribose, as shown in this diagram. DNA is stable to alkaline hydrolysis, because it lacks the free 2 ' - OH on the ribose. Nucleases Nucleases are enzymes that hydrolyze the phosphodiester bonds in nucleic acids. Some are specific for DNA, DNases , and others for RNA, RNases and still others show no specificity.
Endonucleases cleave internal phosphodiester bonds.
Restriction Enzymes Viruses that infect bacteria are called bacteriophages or phages. Phage consist of protein and nucleic acid. Some phage that grow well in one strain of bacteria are often unable to grow well in other strains of bacteria. Phage do not grow because their DNA molecules are cleaved and degraded by enzymes of the host bacterial cell. Degrading DNA destroys the ability of the phage to grow and is responsible for the pattern of growth restriction, hence the bacterial enzymes are called restriction enzymes.