Chlamydia trachomatis major outer membrane protein (MOMP)

Chlamydia trachomatis major outer membrane protein (MOMP) is the predominant protein constituent of the outer membrane of C. trachomatis, comprising up to 60% of the total outer membrane complex protein mass[2][3][6]. It is encoded by the ompA gene and features a primary structure with five constant and four variable domains, the latter conferring serovar-specific antigenicity. MOMP is a trimeric β-barrel porin, forming channels that allow small molecules to diffuse into the bacterium[1][3][7]. Extensive intra- and intermolecular disulfide bonds, some involving other cysteine-rich membrane proteins, provide the outer membrane's structural rigidity, compensating for the absence of classic peptidoglycan in Chlamydia[3][6][7]. As the principal surface-exposed antigen, MOMP is highly immunogenic and an important focus for diagnostic assays and subunit vaccine development. Neutralizing antibodies targeting its variable domains can prevent infection by blocking bacterial adherence to host cells; however, sequence diversity in these domains leads to substantial antigenic variation among strains, presenting a challenge for vaccine design[3].

Other names

Major outer membrane porinChlamydia trachomatis MOMPOuter membrane protein A (OmpA)ompA gene product

Blocking host cell attachment (via monoclonal antibodies against variable domains); Stimulating host immune responses (as a vaccine antigen)