Second of two HU domains found in bacterial proteins typically fused to a C-terminal transmembrane helix and an extracellular peptidoglycan-binding domain. The HU domains in many of these proteins are predicted to function in tethering the nucleoid to the cell envelope [1].

1: Novel clades of the HU/IHF superfamily point to unexpected roles in the eukaryotic centrosome, chromosome partitioning, and biologic conflicts. Burroughs AM, Kaur G, Zhang D, Aravind L; Cell Cycle. 2017;16:1093-1103. PMID:28441108