Under spot test conditions, double mutant arg-4, arg-13 is able to use ornithine as sole nitrogen source and arginine biosynthesis precursor, but subject to strong lysine and canavanine inhibition.

• 在斑点试验条件下,arg-4,arg-13双突变株能利用鸟氨酸作为唯一氮源与精氨酸合成前体,但受赖氨酸与刀豆氨酸强烈抑制。