Forms pores that allow passive diffusion of small molecules across the outer membrane. (Microbial infection) Serves as a less-preferential secondary receptor during phage Sf6 infection; infection requires both lipopolysaccharide (LPS) and (in the absence of OmpA) OmpC can serve as the secondary receptor. Homotrimer. Forms mixed heterotrimers with OmpF and with PhoE; other mixed heterotrimers are also probable. (Microbial infection) Upon infection with phage Sf6 associates with the mature bacteriophage capsid (PubMed:21071053, PubMed:22386055). Was originally suggested to be within the bacteriophage capsid (PubMed:21071053). This has been disproven (PubMed:22386055). (Microbial infection) Upon infection with phage Sf6 is found in extracellular vesicles that associate with the tails of mature bacteriophage particles. No effect on propagation of phage Sf6 (PubMed:22386055). Upon infection with phage Sf6, single deletion mutant has a wild-type level of small plaques with no change in bacterial survival; double ompA-ompC deletions have about 10-fold fewer plaques, survive infection considerably better than wild-type, are infected more slowly and have fewer extracellular vesicles associated with mature bacteriophage (PubMed:24673644). Belongs to the Gram-negative porin family.