passages.id: split_6_test_3262_passage
passages.type: progene_text
passages.text: Gene amplification assays of operons ars1 and ars2 in C. glutamicum revealed that the recombinant strains containing the ars1 operon were resistant to up to 60 mM arsenite , this being one of the highest levels of bacterial resistance to arsenite so far described , whereas recombinant strains containing operon ars2 were resistant to only 20 mM arsenite .