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A Protocol for Computer-Based Protein Structure and Function Prediction
Published on: November 3, 2011
TonB/TolA amino-terminal domain modeling
Kimberly L Keller1, Kerry K Brinkman, Ray A Larsen
1Department of Biological Sciences, Bowling Green State University, Bowling Green, OH, USA.
Methods in Enzymology
|July 5, 2007
Summary
TonB and TolA proteins energize outer membrane processes in bacteria by interacting with membrane complexes. Researchers used protein substitutions to identify key regions involved in this energy transfer.
Area of Science:
- Bacterial outer membrane protein energization
- Protein-protein interactions in bacteria
- Gram-negative bacterial physiology
Background:
- TonB and TolA proteins are crucial energy transducers in Gram-negative bacteria.
- They link the cytoplasmic membrane's ion gradient to outer membrane energy-dependent processes.
- The precise mechanisms of this energy transfer and protein interactions are not fully understood.
Purpose of the Study:
- To elucidate the specific mechanisms of energy transfer mediated by TonB and TolA proteins.
- To identify novel motifs in TonB and TolA involved in interactions with energy harvesting complexes.
- To investigate the roles of amino-terminal signal anchors in protein energization.
Main Methods:
- Characterization of TonB derivatives with multiple-residue substitutions.
- Generation of derivatives via block substitutions with alanyl residues.
- Exchange of short protein regions between TonB and TolA.
Main Results:
- Identified a common motif in the amino-terminal region of TonB and TolA essential for energization.
- Evidence suggests additional, non-shared motifs mediate interactions with specific energy harvesting complexes.
- Characterized specific TonB derivatives to pinpoint interaction regions.
Conclusions:
- The amino-terminal signal anchors of TonB and TolA are vital for protein energization.
- Distinct motifs within TonB and TolA are responsible for specific interactions with energy harvesting complexes.
- Substitution strategies effectively identify functionally important protein regions.
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