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Purification and Visualization of Lipopolysaccharide from Gram-negative Bacteria by Hot Aqueous-phenol Extraction
Published on: May 28, 2012
The bacterial lipocalins
1Department of Laboratory Medicine and Pathobiology, Faculty of Medicine, University of Toronto, 6213 Medical Sciences Building, Toronto, Ont. M5S 1A8, Canada. russell.bishop@utoronto.ca
Biochimica Et Biophysica Acta
|November 4, 2000
Summary
Bacterial lipocalins, initially thought to be eukaryotic, are key outer membrane proteins involved in bacterial functions like antibiotic resistance. Their discovery reveals evolutionary links between bacterial and eukaryotic cells.
Area of Science:
- Microbiology
- Molecular Biology
- Evolutionary Biology
Background:
- Lipocalins were historically considered exclusive to eukaryotes.
- The first bacterial lipocalin (Blc) identified in Escherichia coli is an outer membrane lipoprotein.
- Blc lacks disulfide bonds but shares a membrane anchor with eukaryotic homologues.
Purpose of the Study:
- To investigate the diversity and evolutionary origins of bacterial lipocalins.
- To understand the structure-function relationships of bacterial lipocalins.
- To explore the roles of bacterial lipocalins in cellular processes.
Main Methods:
- Genome sequencing to identify bacterial lipocalins.
- Comparative analysis of lipocalin structures and functions.
- Bioinformatic approaches to trace evolutionary pathways.
Main Results:
- At least 20 distinct bacterial lipocalins have been identified.
- Bacterial lipocalins exhibit varied subcellular localizations (periplasm, membrane, cytosol).
- Evidence suggests horizontal gene transfer from bacteria to eukaryotes.
Conclusions:
- Bacterial lipocalins play diverse roles, including membrane biogenesis, repair, antibiotic resistance, and immunity.
- Lipocalins likely originated in Gram-negative bacteria and were transferred to eukaryotes.
- Studying bacterial lipocalins provides insights into the shared biochemistry of prokaryotic and eukaryotic cells.
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