Crystal structure of TtgV in complex with its DNA operator reveals a general model for cooperative DNA binding of tetrameric gene regulators.

ABSTRACT: The majority of bacterial gene regulators bind as symmetric dimers to palindromic DNA operators of 12-20 base pairs (bp). Multimeric forms of proteins, including tetramers, are able to recognize longer operator sequences in a cooperative manner, although how this is achieved is not well understood due to the lack of complete structural information. Models, instead of structures, of complete tetrameric assembly on DNA exist in literature. Here we present the crystal structures of the multidrug-binding protein TtgV, a gene repressor that controls efflux pumps, alone and in complex with a 42-bp DNA operator containing two TtgV recognition sites at 2.9 Å and 3.4 Å resolution. These structures represent the first full-length functional tetrameric protein in complex with its intact DNA operator

SUBMITTER: Lu D 

PROVIDER: S-EPMC2975931 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature