Lisa A. Mahnke 1992-2000
Resident, Internal Medicine
Washington Univ. School of Medicine, Barnes-Jewish Hospital, St. Louis, MO
Ripon College 1992
Biochemistry PhD 1998
William S Reznikoff
Structure/function studies of the TN5 transposase: Models for inhibition and catalysis
|
| |
|
Tn5 is a transposable DNA element that occurs in gram negative bacteria and shuffles antibiotic resistance genes within genomes. Here, an investigation of structural domains and functional regions in the Tn5 transposase, the catalytic protein responsible for Tn5 DNA cutting and joining, is presented. An N-terminal DNA-binding region has been confirmed and this region appears to be unfolded or flexible in the absence of DNA. A catalytic core domain has been visualized and is structurally similar to two retroviral integrase core domains and to a bacterial transposase core domain, placing the Tn5 transposase in a superfamily of polynucleotidyl transfer enzymes. The active site of the Tn5 transposase has been identified and contains a conserved arginine residue in addition to a characteristic carboxylate residue triad. Two dimerization regions have been identified biochemically, one overlapping with the catalytic domain and one located at the C terminus of the transposase. The C-terminal dimerization domain has been visualized structurally and has been shown to be important for the natural inhibitory mechanism of Tn5 transposition. |
| |
| Thesis Publications |
- Davies DR, Braam LM, Reznikoff WS, Rayment I. The three-dimensional structure of a Tn5 transposase-related protein determined to 2.9-A resolution. J Biol Chem 274:11904-11913, 1999.
- Mahnke Braam LA, Goryshin IY, Reznikoff WS. A mechanism for Tn5 inhibition carboxyl-terminal dimerization. J Biol Chem 274:86-92, 1999.
- Reznikoff WS, Bhasin A, Davies DR, Goryshin IY, Mahnke LA, Naumann T, Rayment I, Steiniger-White M, Twining SS. Tn5: A molecular window on transposition. Biochem Biophys Res Commun 266:729-734, 1999.
- Braam LA, Reznikoff WS. Functional characterization of the Tn5 transposase by limited proteolysis. J Biol Chem 273:10908-10913, 1998.
- Weinreich MD, Mahnke LAB, Reznikoff WS. A functional analysis of the Tn5 transposase: identification of domains required for DNA binding and multimerization. J Mol Biol 241:166-177, 1994.
|
