Dihydrolipoamide Acetyltransferase AceF Influences the Type III Secretion System and Resistance to Oxidative Stresses through RsmY/Z in _Pseudomonas aeruginosa_  
[PERSON]  
1 State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China; [EMAIL_ADDRESS] (H.L. ); [EMAIL_ADDRESS] (Y.X. ); [EMAIL_ADDRESS] (Z.T. ); [EMAIL_ADDRESS] (Y.X. ); [EMAIL_ADDRESS] (F.B. ); [EMAIL_ADDRESS] (Z.C. ); [EMAIL_ADDRESS] (W.W.)  
[PERSON]  
1 State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China; [EMAIL_ADDRESS] (H.L. ); [EMAIL_ADDRESS] (Y.X. ); [EMAIL_ADDRESS] (Z.T. ); [EMAIL_ADDRESS] (Y.X. ); [EMAIL_ADDRESS] (F.B. ); [EMAIL_ADDRESS] (Z.C. ); [EMAIL_ADDRESS] (W.W.)  
Yongxin Jin  
1 State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China; [EMAIL_ADDRESS] (H.L. ); [EMAIL_ADDRESS] (Y.X. ); [EMAIL_ADDRESS] (Z.T. ); [EMAIL_ADDRESS] (Y.X. ); [EMAIL_ADDRESS] (F.B. ); [EMAIL_ADDRESS] (Z.C. ); [EMAIL_ADDRESS] (W.W.)  
[EMAIL_ADDRESS] (W.W.)  
VI secretion systems (T6 SSs) and biofilm formation [11; 12; 13]. The expression of \(rsmY\) and \(rsmZ\) is controlled by the GacS-GacA two-component system [14], whose function is repressed by RetS and activated by LadS [15]. The sensor kinase GacS phosphorylates the response regulator GacA, which binds to the promoters of \(rsmY\) and \(rsmZ\) and activates their transcription [14]. RetS is a hybrid two-component regulator with a sensor kinase domain and two response regulator domains [16]. It has been demonstrated that RetS inhibits the GacS activity through three mechanisms: (1) the siphoning of phosphates from the catalytic domain of GacS; (2) the inhibition of GacS autophosphorylation through direct interaction; and (3) the dephosphorylation of the receiver domain of GacS [16; 17; 18; 19]. A recent study identified host-derived mucin glycans as ligands of RetS. The presence of mucin glycans represses the GacS-GacA two-component system through RetS [20]. Meanwhile, the GacS-GacA two-component system is positively regulated by two hybrid histidine kinases, PA1611 and LadS. PA1611 directly binds to RetS, which counteracts the repressive effect of RetS on GacS [21]. LadS activates the GacS-GacA two-component system by directly phosphorylating GacS [15]. Metabolism plays important roles in bacterial virulence [22]. It has been demonstrated that tryptophan and histidine utilization interfere with the expression of the T3 SS genes in _P. aeruginosa_[23; 24]. The catabolic repression control protein Crc is required for the expression of the T3 SS genes in _P. aeruginosa_[25], indicating a relationship between carbon metabolism and the T3 SS. The function of Crc is antagonized by a small RNA (sRNA), CrcZ [26]. In our previous screening for T3 SS-related carbon metabolism genes, we found that triosephosphate isomerase (TpiA) affects T3 SS gene expression through CrcZ [22]. The isocitrate lyase is required for the expression of the T3 SS genes under oxygen-limited conditions [25]. [PERSON] et al. found that transposon insertions in genes encoding the pyruvate dehydrogenase (PDH) subunits AceE and AceF (previously called AceA and AceB) resulted in the defective expression of the T3 SS genes upon Ca\({}^{2+}\) depletion, which was restored by expression of _exsA_ in trans [27]. A mutation in the E1 subunit (AceA/AceE) of pyruvate dehydrogenase resulted in the defective expression of _exoS_ in response to Ca\({}^{2+}\) depletion in a minimal medium containing 0.1% tryptone and glutamate [28].