Van der Waals interaction is the weakest of all intermolecular attractions between molecules.

#Id: 2755

#Unit 13. Methods in Biology

Linker and/or adapter molecules can be joined to the cut ends. Linkers are short, chemically synthesized, double-stranded oligonucleotides, which contain within them one or more restriction endonuclease sites, e.g., linker 5'CCGAATTCGG (only one strand of the linker is shown here) contains one EcoRI site. 

#Id: 2756

#Unit 13. Methods in Biology

Linkers are fused with blunt-ended DNA fragments; cleavage of the linker with the appropriate restriction enzyme creates suitable cohesive protruding ends.

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#Unit 13. Methods in Biology

Linkers have the following two applications: creation of cohesive 'ends

on blunt~ended DNA fragments, and 

on fragments having unmatched or undefined sequences in their protruding ends. 

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#Unit 13. Methods in Biology

Examples of adapters. 

An adapter used to create BamHI sticky ends at the blunt ends of a DNA insert. 

A conversion adapter produced by associating two oligonucleotides, each having a different recognition sequence at its 5'~end but a complementary sequence for base pairing at the 3 '-end. 

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#Unit 13. Methods in Biology

Adapters are short, chemically synthesized DNA double strands, which already have one or both sticky ends. 

#Id: 2760

#Unit 13. Methods in Biology

 A gel mobility shift assay detects interaction between a protein and DNA by the reduction of the electrophoretic mobility of a small DNA that occurs on binding to a protein.