Corynebacterium glutamicum can degrade phenol by a meta-cleavage pathway, which depends on ncgl2588 (phe) of the phe operon encoding phenol hydroxylase. An additional gene, ncgl2587 (pheR), is located upstream of phe. The pheR encodes an AraC/XylR-type regulator protein with 377 amino acid residues and is transcribed in the same direction as phe. Disruption of pheR by homologous recombination resulted in the accumulation of phenol in C. glutamicum. PheR demonstrates a low type of constitutive expression where phenol induces phe expression. PheR shares 75% sequence identity with AraC-type regulator of Corynebacterium lubricantis and 37 conserved residues, characteristic of AraC family, were located. A constructed pK18mobsacB-P_phe:lacZ transcriptional fusion plasmid was transformed into the wild-type, ΔpheR, and ΔpheR⁺ strains, and the results indicated that PheR activates the expression of phe encoding phenol hydroxylase. Electrophoretic mobility shift assay (EMSA) demonstrated a direct interaction of PheR with the phe promoter region and binding site of PheR on the P_phe was located 109-bp upstream of phe, as indicated by foot printing analysis. Our research provides deep insight into PheR expression and its regulatory function on Phe in C. glutamicum.

谷氨酸棒杆菌可以通过元裂解途径降解苯酚，这取决于编码酚羟化酶的phe操纵子的ncgl2588（phe）。另一个基因ncgl2587（pheR）位于phe的上游。所述PHER编码阿糖胞苷/ XylR型调节蛋白与377个氨基酸残基，并在相同的方向上被转录PHE。同源重组破坏pheR导致苯酚在谷氨酸棒状杆菌中的积累。PheR表现出低水平的组成型表达，其中酚诱导phe表达。PheR与棒状杆菌的AraC型调节子具有75％的序列同一性，并且找到了37个保守的残基，这些残基是AraC家族的特征。将构建的pK18 mobsacB-P _phe：lacZ转录融合质粒转化到野生型ΔpheR和ΔpheR ⁺菌株中，结果表明PheR激活了编码苯酚羟化酶的phe的表达。电泳迁移率变动分析（EMSA）证明PHER的与一个直接相互作用PHE启动子区域和在P PHER的结合位点_PHE位于109-bp的上游PHE，如脚印分析所示。我们的研究为谷氨酸谷氨酸中PheR表达及其对Phe的调控功能提供了深刻的见识。