Effect of zinc ions on the biochemical behavior of simian virus 40 small-t antigen expressed in bacteria.
The simian virus 40 small-t antigen contains 10 cysteine residues, 6 of which are organized in two CysXCysXXCys clusters. Mutation of individual Cys residues in the two clusters or mutation of specific residues found between these clusters causes pronounced instability of the protein in animal cells. Protein instability correlates with failure of the bacterially expressed mutant proteins to bind zinc ions, an interaction which allows purification of large amounts of small-t antigen in monomeric form.
Goswami
R
R
Department of Microbiology-Immunology, Northwestern University, Chicago, Illinois 60611.
Turk
B
B
Enderle
K
K
Howe
A
A
Rundell
K
K
D000595:Amino Acid Sequence; D000952:Antigens, Polyomavirus Transforming / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D001483:Base Sequence; D003545:Cysteine / Q000737:chemistry; D004252:DNA Mutational Analysis; D008667:Metalloproteins / Q000737:chemistry; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides / Q000737:chemistry; D016133:Polymerase Chain Reaction; D011994:Recombinant Proteins / Q000737:chemistry; D013539:Simian virus 40 / Q000502:physiology*; D015032:Zinc / Q000737:chemistry* / Q000378:metabolism
D000952:Antigens, Polyomavirus Transforming; D008667:Metalloproteins; D009838:Oligodeoxyribonucleotides; D011994:Recombinant Proteins; D015032:Zinc; D003545:Cysteine