Premium
Similarities in the structure of the transcriptional repressor AmtR in two different space groups suggest a model for the interaction with GlnK
Author(s) -
Sevvana Madhumati,
Hasselt Kristin,
Grau Florian C.,
Burkovski Andreas,
Muller Yves A.
Publication year - 2017
Publication title -
acta crystallographica section f
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.572
H-Index - 37
ISSN - 2053-230X
DOI - 10.1107/s2053230x17002485
Subject(s) - tetr , corynebacterium glutamicum , repressor , biology , effector , biochemistry , protein quaternary structure , amino acid , stereochemistry , chemistry , transcription factor , gene , protein subunit
AmtR belongs to the TetR family of transcription regulators and is a global nitrogen regulator that is induced under nitrogen‐starvation conditions in Corynebacterium glutamicum . AmtR regulates the expression of transporters and enzymes for the assimilation of ammonium and alternative nitrogen sources, for example urea, amino acids etc . The recognition of operator DNA by homodimeric AmtR is not regulated by small‐molecule effectors as in other TetR‐family members but by a trimeric adenylylated P II ‐type signal transduction protein named GlnK. The crystal structure of ligand‐free AmtR (AmtR orth ) has been solved at a resolution of 2.1 Å in space group P 2 1 2 1 2. Comparison of its quaternary assembly with the previously solved native AmtR structure (PDB entry 5dy1) in a trigonal crystal system (AmtR tri ) not only shows how a solvent‐content reduction triggers a space‐group switch but also suggests a model for how dimeric AmtR might stoichiometrically interact with trimeric adenylylated GlnK.