Selenomethionine properties

There is also a significant occurrence of nonprotein D-amino acids in nature.These amino acids have attractive structural variations and remarkable biological properties. However, this chapter will not include details on nonprotein D-amino acids. Selenium-containing amino acids, such as selenocysteine and selenomethionine, are also considered as unusual amino acids. Recently, much interest in selenium-containing amino acids has emerged. More information about selenium-containing amino acids is available in Chapter 5.05. 

Shepherd, L. and Huber, R.E. 1969. Some chemical and biochemical properties of selenomethionine. 

Nonstandard amino acids can be either incorporated globally at multiple sites within a protein or inserted at specific locations (1, 15). Global misincorporation of nonstandard amino acids can produce protein polymers with altered physical properties that confer, for example, varied tensile strengths and elasticities (16). These unique biomaterials can be used in many medical applications, such as altering properties associated with cell adhesion. In other applications, routine replacement of methionine by selenomethionine aids in X-ray crystal structure determination. 

Property Selenium dioxide Selenium trioxide Selenocystine Selenomethionine... 

NMR utihzes the magnetic properties of number of nuclei [4,5], However, from the point of view of peptides analysis only few isotopes can be though as a structural probes. The most important are H, and N isotopes representing the basic building units of peptides. In some cases, Se or nuclei are employed in structural analysis when appropriate derivatives (cysteine, selenomethionine or phosphorylated peptides) are under investigation. AH of the above mentioned nuclei have 14 spin and are relatively easy to measure however, in many cases simple one-pulse acquisition fails. Below, we will show how today these problems can be overcome. 

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