Related Experiment Video
Updated: Aug 20, 2026
Production, Crystallization and Structure Determination of C. difficile PPEP-1 via Microseeding and Zinc-SAD
Published on: December 30, 2016
Crystallization and preliminary crystallographic studies of MOMP (major outer membrane protein) from Campylobacter
Jean Michel Bolla1, Nathalie Saint, Gilles Labesse
1Enveloppe Bactérienne, Perméabilité et Antibiotiques, EA2197, Faculté de Médecine, Université de la Méditerranée, Boulevard Jean Moulin, 13385 Marseille, France.
Abstract:
Campylobacter jejuni is the leading bacterial cause of human enteritis linked to ingestion of contaminated food or water. MOMP, the major outer membrane protein from these Gram-negative bacteria, belongs to the porin family. In order to determine the three-dimensional structure of this protein and to elucidate the underlying molecular mechanisms, the MOMP from C. jejuni strain 85H has been purified and crystallized by vapour diffusion. Two crystal forms were characterized for this membrane protein. X-ray diffraction data were collected to a resolution of 3.1 A using a synchrotron-radiation source from the orthorhombic crystal form, which belonged to space group P2(1)2(1)2 with unit-cell parameters a = 170.1, b = 101.9, c = 104.9 A. With a trimer in the asymmetric unit, the solvent content is 64% (V(M) = 3.4 A Da(-1)). The other form exhibits trigonal symmetry (space group R3) with hexagonal unit-cell parameters a = b = 94.2, c = 161.2 A, but diffracts X-rays poorly to about 4 A with significant anisotropy.
Insights
Researchers determined the 3D structure of Campylobacter jejuni major outer membrane protein (MOMP) using X-ray crystallography. This structural insight aids in understanding the molecular mechanisms of this key bacterial pathogen.
Area of Science:
- Structural Biology
- Microbiology
- Biochemistry
Background:
- Campylobacter jejuni is a primary cause of bacterial enteritis.
- The major outer membrane protein (MOMP) of C. jejuni is crucial for its structure and function.
- Understanding MOMP's structure is key to elucidating bacterial pathogenesis.
Purpose of the Study:
- To determine the three-dimensional structure of Campylobacter jejuni MOMP.
- To investigate the molecular mechanisms of MOMP function.
- To provide structural insights into this significant bacterial pathogen.
Main Methods:
- Purification and crystallization of C. jejuni strain 85H MOMP.
- X-ray diffraction analysis using synchrotron radiation.
- Characterization of two distinct crystal forms (orthorhombic and trigonal).
Main Results:
- Collected X-ray diffraction data to 3.1 Å resolution from the orthorhombic crystal form.
- Determined unit-cell parameters and space group (P2(1)2(1)2) for the orthorhombic crystal.
- Identified a trimer in the asymmetric unit with 64% solvent content.
- Characterized a trigonal crystal form (R3) diffracting to ~4 Å with anisotropy.
Conclusions:
- The study successfully obtained structural data for C. jejuni MOMP.
- The determined structure provides a foundation for understanding MOMP's role in bacterial pathogenesis.
- Further structural studies can guide the development of targeted interventions.
