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Isolation of Physiologically Active Thylakoids and Their Use in Energy-Dependent Protein Transport Assays
Published on: September 28, 2018
Substrate recognition by proline permease in Salmonella
1Department of Biology, Furman University, Greenville, South Carolina 29613-1118, USA. Min-ken.liao@furman.edu
Amino Acids
|October 23, 2001
Summary
Researchers identified key structural features of the proline permease (PutP) in enteric bacteria. This understanding may help design inhibitors to block proline uptake in microbial pathogens.
Area of Science:
- Microbiology
- Biochemistry
- Structural Biology
Background:
- Proline transport is crucial for microbial metabolism and stress adaptation.
- It also plays a significant role in the virulence of various pathogens.
- The putP gene encodes the major proline permease in enteric bacteria.
Purpose of the Study:
- To elucidate the structural requirements for substrate recognition by the PutP proline permease.
- To guide the design of novel inhibitors targeting proline transport in pathogens.
Main Methods:
- Assaying transport and toxicity of proline derivatives.
- Analyzing structural interactions between substrates and the permease binding site.
Main Results:
- The PutP binding site features a hydrophobic pocket accommodating pyrrolidine rings (4- and 5-membered) but excluding 6-membered rings.
- Substituents at the C4 position are not tolerated.
- A hydrophilic region recognizes imino and carbonyl groups; a free carboxyl group is not essential.
Conclusions:
- The substrate specificity of PutP is defined by specific hydrophobic and hydrophilic interactions.
- These findings provide a basis for developing synthetic inhibitors of proline transport.
- Inhibiting proline uptake could be a strategy to combat microbial pathogens.
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