aatA

AatA is a gene symbol used in microbiology, most notably referring to an outer membrane protein that is part of a bacterial secretion system. In Enteroaggregative Escherichia coli (EAEC), AatA is described as the outer membrane component of the Aat secretion system, which exports virulence factors such as dispersin (Aap) to the exterior of the cell.

In the EAEC dispersin export system, commonly designated as the AatPABC or related operon, AatA works with other Aat proteins to form a channel through which substrates are secreted across the outer membrane. AatA is often characterized as a TolC-like outer membrane protein, partnering with inner membrane and periplasmic components to enable the secretion process. This system is associated with surface colonization and biofilm formation, contributing to the pathogenic lifestyle of EAEC strains.

Genetic context and variability: The aatA gene is typically found in EAEC strains and is frequently part of a virulence gene cluster that can be plasmid-borne or chromosomally integrated. The exact arrangement and sequence can vary among strains, reflecting mobile genetic elements that carry virulence factors.

Other uses and cautions: The symbol aatA may be used for different genes in other organisms, or in different genomic annotations, so functional interpretation should be grounded in the specific organism and study. When encountering aatA in genomic data, consult the organism’s annotation or primary literature to confirm the gene’s function.

See also: dispersin (Aap), AatP, AatB, AatC, AatD, enteroaggregative Escherichia coli (EAEC).