contains similarity to Pfam domains PF13598 (Domain of unknown function (DUF4139)), PF13600 (N-terminal domain of unknown function (DUF4140)); contains similarity to Interpro domains IPR011935 (Conserved hypothetical protein CHP02231), IPR037291 (Domain of unknown function DUF4139), IPR025554 (Domain of unknown function DUF4140)