Probable RNase involved in rRNA stability through maturation and/or degradation of precursor rRNAs. Preferentially cleaves UA sequences in the 5' precursor region of 5S rRNA (PubMed:28978920). Binds to RNA in loop regions with AU-rich sequences (By similarity). Deletion mutant shows a delay of exponential phase, reduction of maximum cell number and significant changes in the nucleotide sequence lengths of its 5S, 16S, and 23S rRNAs in early exponential phase. Belongs to the FAU-1 family.