Strains.

*Δ, deletion of genes/sites.:: indicates deletion-substitution when an antibiotic resistance cassette or EGFP is inserted in the indicated gene, but insertion when a site (loxP/SGS) or Mu is inserted. :: placed on both sides of a site indicates insertion of that site between the neighboring genes, the exact location given in Table S1.*Δ：表示基因/位点的缺失。:: 表示：若在指定基因中插入抗生素抗性盒或增强型绿色荧光蛋白（EGFP），则为缺失-替换突变；若在指定位点（loxP/SGS）或Mu中插入该序列，则为插入突变。:: 当该符号置于位点两侧时，表示将该位点插入相邻基因之间，具体位置详见表S1。