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Role of tyrosine 33 residue for the stabilization of the tetrameric structure of human cytidine deaminase.

ABSTRACT: In the present work the effect of a mutation on tyrosine 33 residue (Y33G) of human cytidine deaminase (CDA) was investigated with regard to protein solubility and specific activity. Osmolytes and CDA ligands were used to increase the yield and the specific activity of the protein. The mutant enzyme was purified and subjected to a kinetic characterization and to stability studies. These investigations reinforced the hypothesis that in human CDA the side chain of Y33 is involved in intersubunit interactions with four glutamate residues (E108) forming a double latch that connects each of the two pairs of monomers of the tetrameric CDA.

SUBMITTER: Micozzi D

PROVIDER: S-EPMC3020594 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature

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Role of tyrosine 33 residue for the stabilization of the tetrameric structure of human cytidine deaminase.

Micozzi Daniela D Pucciarelli Stefania S Carpi Francesco M FM Costanzi Stefano S De Sanctis Giampiero G Polzonetti Valeria V Natalini Paolo P Santarelli Ivano F IF Vita Alberto A Vincenzetti Silvia S

International journal of biological macromolecules 20100714 4

In the present work the effect of a mutation on tyrosine 33 residue (Y33G) of human cytidine deaminase (CDA) was investigated with regard to protein solubility and specific activity. Osmolytes and CDA ligands were used to increase the yield and the specific activity of the protein. The mutant enzyme was purified and subjected to a kinetic characterization and to stability studies. These investigations reinforced the hypothesis that in human CDA the side chain of Y33 is involved in intersubunit i ...[more]

PMID: 20637228

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