The members of this family are similar to a region close to the C-terminus of the HipA protein expressed by various bacterial species (for example Swiss:P23874). This protein is known to be involved in high-frequency persistence to the lethal effects of inhibition of either DNA or peptidoglycan synthesis [1]. When expressed alone, it is toxic to bacterial cells [1], but it is usually tightly associated with HipB [2], and the HipA-HipB complex may be involved in autoregulation of the hip operon. The hip proteins may be involved in cell division control and may interact with cell division genes or their products [2].

1: Structure and organization of hip, an operon that affects lethality due to inhibition of peptidoglycan or DNA synthesis. Black DS, Kelly AJ, Mardis MJ, Moyed HS; J Bacteriol 1991;173:5732-5739. PMID:1715862

2: Autoregulation of hip, an operon that affects lethality due to inhibition of peptidoglycan or DNA synthesis. Black DS, Irwin B, Moyed HS; J Bacteriol 1994;176:4081-4091. PMID:8021189