. "This protein is found in bacteria. Proteins in this family aretypically between 136 to 150 amino acids in length. The opportunistic pathogen Mycobacterium smegmatis is resistant to rifampin because of the presence of a chromosomally encoded rifampin ADP-ribosyltransferase (Arr-ms). Arr-ms is a small enzyme whose activity thus renders rifamycin antibiotics ineffective [2]. " . "Arr-ms" . "Rifampin ADP-ribosyl transferase" . "Mistry J, Gavin OL" . "Domain" . . . . . . . . . . . . . . . . .