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Related Experiment Video

Updated: Jul 10, 2026

Specificity Analysis of Protein Lysine Methyltransferases Using SPOT Peptide Arrays

Specificity Analysis of Protein Lysine Methyltransferases Using SPOT Peptide Arrays

Published on: November 29, 2014

Structural insight into OprD substrate specificity.

Shyamasri Biswas¹, Mohammad M Mohammad, Dimki R Patel

¹Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA.

Nature Structural & Molecular Biology

|October 24, 2007

Summary

The crystal structure of Pseudomonas aeruginosa OprD reveals a narrow pore with charged regions. This structure likely represents the general architecture of OprD channels in bacteria.

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Last Updated: Jul 10, 2026

Specificity Analysis of Protein Lysine Methyltransferases Using SPOT Peptide Arrays

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Published on: November 29, 2014

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Defining Substrate Specificities for Lipase and Phospholipase Candidates

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Published on: November 23, 2016

Area of Science:

Structural biology
Microbiology
Biochemistry

Background:

OprD proteins are crucial outer-membrane channels in Gram-negative bacteria.
These channels exhibit substrate specificity, playing roles in nutrient uptake and metabolite transport.

Purpose of the Study:

To determine the X-ray crystal structure of the OprD protein from Pseudomonas aeruginosa.
To elucidate the structural basis for OprD channel function and substrate selectivity.

Main Methods:

X-ray crystallography was employed to obtain the high-resolution structure of OprD.
Structural analysis focused on pore architecture, charge distribution, and conserved residues.

Main Results:

The structure reveals OprD as a monomeric 18-stranded beta-barrel.
A narrow pore constriction features a positively charged 'basic ladder' and an electronegative pocket.
Conserved residues are strategically located, suggesting a conserved structural motif.

Conclusions:

The determined structure provides unprecedented insight into the molecular architecture of OprD channels.
The findings suggest a conserved structural framework for OprD family proteins across different Gram-negative bacteria.
This structural information is vital for understanding OprD-mediated transport and potential drug development targeting bacterial outer membranes.