Conformational changes recognition

Substrates and enzymes induce mutual conformational changes in one another that facihtate substrate recognition and catalysis. 

A more subtle example of homochiral preference, which draws attention to the conformational changes in the molecules needed to achieve self-recognition, is that... 

Antigen antibody recognition is dependent on protein structure. A conformational change in a protein caused by formalin fixation may mask the epitope and thus affect the antigenicity of proteins in formalin-treated tissue (Montero 2003). The antigen retrieval leads to a renaturation or at least partial restoration of the protein structure, with re-establishment of the three-dimensional protein structure to something approaching its native condition (Shi et al. 1991). 

Cusack, S., Yaremchuk, A., and Tukalo, M. (1996). The crystal structures of T. thermophilus lysyl-tRNA synthetase complexed with E. coli tRNA(Lys) and a T. thermophilus tRNA (Lys) transcript anticodon recognition and conformational changes upon binding of a lysyl-adenylate analogue. EM BO J. 15, 6321—6334. 

The basic principle of this method of recognition is a cation-induced conformational change bringing closer together (or moving away) two moieties able to interact and induce photophysical effects excimer or exciplex formation (or disappearance), electronic energy transfer and quenching. 

Recently it was shown that introduction of fluorescent groups into ionophoric calix[4]arenes provides new systems for recognition of alkali metal ions.<59 62) Because of the mobility of the phenyl units, conformational changes can be induced by solvents and metal ions. Examples are given in Figure 2.15. 

The initial event is the binding of ferri-heme to hemopexin in the plasma, which induces a conformational change in the protein and enables high-affinity molecular recognition by cells expressing the... 

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