The third major region of protein-DNA interactions is the flexible loop, residues 12-20.

Residues 12-20 form flexible loops immediately preceding each β -strand.

The central T-A dinucleotide step showing the interactions of the phosphate backbone with the flexible 12-20 loop.

The proteins are completely helical, and a flexible loop, involved in L-tryptophan binding, is observed just outside the active-site pocket.

Dimerization is thought to stabilize a "flexible loop" located close to the active site.

The main recognition site is a flexible loop at the a3 domain of an MHC molecule.

The cars ride inside a single large vertical loop, pulled along by a flexible inner loop, Mr. Cashman said.

Additionaly, at one end of the active site there is a flexible loop that provides sufficient room for long carbon chains.

There are two flexible loops call the B-loop and T-loop which are involved in regulation of the protein.

Tight turns and loose, flexible loops link the more "regular" secondary structure elements.