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Updated: May 24, 2026
08:53
Biochemical and Structural Characterization of the Carbohydrate Transport Substrate-binding-protein SP0092
Published on: October 2, 2017
The structural basis of transferrin sequestration by transferrin-binding protein B
Charles Calmettes1, Joenel Alcantara, Rong-Hua Yu
1Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada.
Nature Structural & Molecular Biology
|February 21, 2012
Summary
Neisseria meningitidis uses TbpB to capture iron from human transferrin, a crucial step in causing meningitis. Crystal structures reveal how this bacterial protein binds and initiates iron release from transferrin.
Area of Science:
- Microbiology
- Structural Biology
- Infectious Diseases
Background:
- Neisseria meningitidis causes bacterial meningitis.
- Iron acquisition is vital for Neisseria meningitidis survival.
- The TbpA-TbpB system mediates iron uptake from transferrin.
Purpose of the Study:
- To elucidate the structural mechanism of iron acquisition by Neisseria meningitidis.
- To determine the crystal structures of TbpB in its apo and transferrin-bound forms.
Main Methods:
- X-ray crystallography
- Protein structure determination
- Complex formation analysis
Main Results:
- Crystal structures of TbpB (apo and human transferrin-bound) were determined.
- The structures reveal TbpB's mechanism for sequestering human transferrin.
- The mechanism for initiating iron release from transferrin by TbpB is elucidated.
Conclusions:
- TbpB plays a critical role in Neisseria meningitidis's iron acquisition strategy.
- Structural insights into TbpB-transferrin interaction can inform therapeutic strategies against meningitis.
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