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Updated: Jul 8, 2026
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Fluorescence-Based Measurements of Phosphatidylserine/Phosphatidylinositol 4-Phosphate Exchange Between Membranes
Published on: March 14, 2021
The phagosomal nutrient transporter (Pht) family
Derek E Chen1, Sheila Podell2, John-Demian Sauer3
1Division of Biological Sciences, University of California at San Diego, La Jolla, CA 92093-0116, USA.
Microbiology (Reading, England)
|January 5, 2008
Summary
Phagosomal transporters (Phts), essential for Legionella pneumophila growth, represent a new bacterial protein family. This study characterizes Phts and a related family, revealing their evolutionary origins and evidence of horizontal gene transfer.
Area of Science:
- Molecular biology
- Microbiology
- Bioinformatics
Background:
- Phagosomal transporters (Phts) are crucial for Legionella pneumophila intracellular development.
- Phts belong to the major facilitator superfamily (MFS), a novel family of bacterial multispanning alpha-helical proteins.
Purpose of the Study:
- To characterize the Pht protein family and its evolutionary relationship with other MFS members.
- To investigate the origin and potential horizontal gene transfer of Pht family genes.
Main Methods:
- Phylogenetic analysis of Pht protein sequences.
- Topological analysis to predict protein structure.
- Motif identification and statistical analysis for evolutionary insights.
Main Results:
- Pht proteins exhibit a probable 12 alpha-helical transmembrane segment topology.
- Evidence suggests Pht proteins evolved from a six TMS precursor via intragenic duplication.
- Phylogenetic analysis identified potential orthologous relationships and instances of horizontal gene transfer.
Conclusions:
- Two novel MFS families, Pht and UMF9, are characterized.
- Horizontal gene transfer played a role in the distribution of some Pht family members.
- Pht and UMF9 families show distinct paralogue numbers and organismal distribution.
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