passages.id: split_6_test_1671_passage
passages.type: progene_text
passages.text: Ask activity of ' A. lactamdurans ' is regulated by the concerted action of lysine plus threonine and this inhibition is abolished in E. coli transformants containing Ser ( 301 ) to Tyr , or Gly ( 345 ) to Asp mutations of the ' A. lactamdurans ' ask gene .