HNS-dependent expression A (IPR024972)

Short name: HdeA

Overlapping homologous superfamilies

Family relationships


HNS (histone-like nucleoid structuring)-dependent expression A (HdeA) protein is a stress response protein found in highly acid resistant bacteria such as Shigella flexneri and Escherichia coli, but which is lacking in mildly acid tolerant bacteria such as Salmonella [PMID: 10623550]. HdeA is one of the most abundant proteins found in the periplasmic space of E. coli, where it is one of a network of proteins that confer an acid resistance phenotype essential for the pathogenesis of enteric bacteria [PMID: 12694615]. HdeA is thought to act as a chaperone, functioning to prevent the aggregation of periplasmic proteins denatured under acidic conditions. The HNS protein, a chromatin-associated protein that influences the gene expression of several environmentally-induced target genes, represses the expression of HdeA. HdeB, which is encoded within the same operon, may form heterodimers with HdeA. HdeA is a single domain alpha-helical [PMID: 10623550] protein with an overall fold that is similar to the fold of the N-terminal subdomain of the GluRS anticodon-binding domain.

This entry represents acid stress chaperone HdeA.

GO terms

Biological Process

GO:0071468 cellular response to acidic pH

Molecular Function

No terms assigned in this category.

Cellular Component

GO:0030288 outer membrane-bounded periplasmic space

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.