Takahashi K
J Biochem. 1976 Nov;80(5):1173-6. doi: 10.1093/oxfordjournals.jbchem.a131373.
Ninhydrin (1)2,3-indantrione monohydrate) was shown to react with the guanidino group of Nalpha-benzyloxycarbonylarginine under mild conditions (pH 8.0, 25 degrees). When ribonuclease A [EC 3.1.4.22] was reacted with ninhydrin under similar conditions, rapid inactivation took place with concomitant modification of arginine and lysine residues. Specific modification of arginine residues in the enzyme could be achieved by reversible blocking of amino groups with citraconic anhydride. Ribonuclease T1 [EC 3.1.4.8] was also inactivated rapidly by ninhydrin under similar conditions. In this case, the single arginine residue (Arg-77) and the amino groups of the N-terminal alanine and lysine-41 appeared to be specifically modified. Other amino acid residues did not appear to be significantly modified by ninhydrin in either of these enzymes. Ninhydrin thus can be used for the specific modification of arginine residues in proteins under mild conditions by reversibly blocking amino and, possibly, thiol groups.
茚三酮（1,2,3 - 茚三酮一水合物）在温和条件下（pH 8.0，25℃）可与Nα - 苄氧羰基精氨酸的胍基发生反应。当核糖核酸酶A[EC 3.1.4.22]在类似条件下与茚三酮反应时，会迅速失活，同时精氨酸和赖氨酸残基发生修饰。通过用柠康酸酐可逆地封闭氨基，可以实现对该酶中精氨酸残基的特异性修饰。核糖核酸酶T1[EC 3.1.4.8]在类似条件下也会被茚三酮迅速灭活。在这种情况下，单个精氨酸残基（Arg - 77）以及N端丙氨酸和赖氨酸 - 41的氨基似乎被特异性修饰。在这两种酶中，其他氨基酸残基似乎未被茚三酮显著修饰。因此，茚三酮可用于在温和条件下通过可逆地封闭氨基以及可能的巯基来特异性修饰蛋白质中的精氨酸残基。
