Return to search

Oligomerization of the lysr-type transcriptional regulators in Escherichia Coli

Protein-protein interactions regulate and drive biological processes and
understanding the assembly of these interactions is important. The LysR-Type
Transcriptional Regulators (LTTRs) are a large family of transcriptional regulators
found in prokaryotes. I have used the LTTRs as a model for protein specificity. In order
to understand a residue’s contribution to oligomerization, alanine-scanning mutagenesis
was used to probe the contribution of residues identified from in silico analysis of two
proteins: OxyR and CynR. The contribution of the residues to oligomerization was
characterized using lcI repressor fusions. In OxyR, seven residues were identified as
hot spots. Moreover, these hot spots are not especially conserved. The interaction surface
of OxyR was mapped onto a multiple sequence alignment of the LTTR family. This
mapping identified putative contacts in the CynR regulatory domain dimer interface.
Combined with the in vivo testing, three residues were identified as hot spots. The
residues identified in OxyR and CynR do not overlap. To investigate the assembly of the
LTTRs I used a negative-dominance assay with lcI repressor fusions. Taken together, I
show that the LTTRs in E. coli K-12 are mostly specific in their interactions.

Identiferoai:union.ndltd.org:tamu.edu/oai:repository.tamu.edu:1969.1/ETD-TAMU-2655
Date15 May 2009
CreatorsKnapp, Gwendowlyn Sue
ContributorsHu, James C
Source SetsTexas A and M University
Languageen_US
Detected LanguageEnglish
TypeBook, Thesis, Electronic Dissertation, text
Formatelectronic, application/pdf, born digital

Page generated in 0.0018 seconds