Effects of his-tags on physical properties of parvalbumins

April 9, 2019


Effects of his-tags on physical properties of parvalbumins


Alisa A. Vologzhannikova, Polina A. Khorn, Alexei S. Kazakov, Eugene A. Permyakov, Vladimir N. Uversky, Sergei E. Permyakov




Cell Calcium


A comparative study of His-tagged and non-tagged rat β-parvalbumin (rWT β-PA), calcium binding protein with the EF-hand calcium binding domains, has been carried out. The attachment of His-tag increases α-helical content and decreases β-sheets and β-turns content of the metal free form (apo-state) of β-PA. In contrast to this, the attachment of His-tag decreases α-helical content by more than 10% and increases contents of β-sheets and β-turns of the Ca2+-loaded state. According to the dynamic light scattering analysis, apo-state of His-tagged rat β-PA seems to be less compact compared with the apo-state of non-tagged rat β-PA. Surprisingly, the attachment of His-tag practically does not change mean hydrodynamic radius of Ca2+-loaded rat β-PA. The attachment of His-tag shifts thermal denaturation peaks of both apo- and Ca2+-loaded states of rat β-PA towards higher temperatures by 3–4 °C and slightly decreases its Ca2+ affinity. These results should be taken into consideration in the use of His-tagged parvalbumins.




Circular dichroism, Secondary structure, Chemical stability, Biochemistry