Abstract
The bacteriophage T4 α- and β-glucosyltransferases (AGT and BGT) catalyse the transfer of glucose from uridine diphosphoglucose to 5-hydroxymethyl cytosine of T4 DNA in an α- and β-conformation, respectively. Following the 3D structure of BGT and a secondary structure alignment of AGT and BGT, we performed a site-directed mutagenesis of AGT. A two-domain structure was deduced, with an open substrate-free and a closed substrate-bound conformation. We also identified specific amino acids involved in DNA binding. The identification of a protein-protein interaction of AGT and gp45 which is a part of the T4 replication complex supports the idea that T4 DNA is α-glucosylated immediately after synthesis. BGT then glucosylates those hydroxymethyl cytosines not previously served by AGT.
| Original language | English |
|---|---|
| Journal | Biochemical and Biophysical Research Communications |
| Volume | 323 |
| Issue number | 3 |
| Pages (from-to) | 809-815 |
| Number of pages | 7 |
| ISSN | 0006-291X |
| DOIs | |
| Publication status | Published - 22.10.2004 |
Funding
We thank U. Aschke for excellent technical assistance, P.S. Freemont for kind support for the in silico works, and P. van der Heusen for the generous gift of purified gene product 45. W.R. gratefully acknowledges the financial support of the Deutsche Forschungsgemeinschaft through Grant RU 123/26-1 and 26-2, and of the Deutscher Akademischer Austauschdienst through Grant 313/ARC-scu. Appendix
