## 3 Discussion
\begin{table}
\begin{tabular}{l l l} \hline \hline
**List of Transcriptionnal Regulators and Regulatory Protein kinases** & **Impact on Act Biosynth** \\ \hline
**Regulation of Phosphate and/or Nitrogen up-take and assimilation** & & \\   PhoR/SCO4229-PhoP/SCO4230 & Neg [77; 78] \\
**Mur-SCOO3013** & Neg [181] \\
**GlnR/SCO4159** & Neg [86] \\
**DasR/SCO5231 (Regulation of N-acetylglucosamine metabolism)** &? \\
**Nank/SCO2958 (Regu of nitrate-nitrite up-take and assimilation)** & (Neg?) \\
**SCO7699/EshA (Stringent response)** & Pos [159] \\
**Cell wall stress** & & \\
**SigE/SCO356** & Neg [42; 44] \\
**SigU/SCO2954** &? \\
**TCS Ces/SCO358 (SCO3359)** & Neg [42] \\
**TCS Vank/VanS** &? \\
**HypR/SCO6294 (?)** &? \\
**Osmotic stress** &? \\
**(**SigB\({}^{\text{ND}}\)/SCO6000)** & (Neg?) \\
**SigH/SCO5243** &? \\
**SCO5244 (anti-sigma factor H)** &? \\
**BldG/SCO3549 (anti-sigma factor)** & Pos [36] \\
**TCS Ohk/Orra (SCO1596/SCO3008)** & Neg [94; 95] \\
**TCS Oaa/SCO5748-OasB/SCO5749** & Neg [61] \\
**Prst/SCO3066 (Anti sigma I factor)** &? \\
**Oxulative Stress** &? \\
**WblA/SCO3579** & Neg [101] \\
**SigR/SCO5216** & (Neg?) \\
**SCO2647 (MarR-like regulator)** & (Neg?) \\
**SOO180 (Fun-like regulator)** & (Neg?) \\
**SigN/SCO4034 (general stress response)** & Pos [49; 50] \\
**Mel homeostasis** & & \\
**TCS CutR/SCO5862-CutS/SCO5863 (copper homeostasis)** & Neg [104] \\
**TCS Rap1/SCO5403-RapA2/SCO5404 (copper homeostasis?)** & Pos [110] \\
**SCO5087** (regulator of the cobaltation biosynthetic cluster/zinc homeostasis) &? \\
**DmdR1/SCO4394 (regulator of the desiferoxamine biosynthetic cluster/iron homeostasis)** &? \\
**AbsC/SCO5405 (MarR-like regulator/zinc homeostasis)** & Neg [183] \\
**Zur** & **SCO2508 (zinc homeostasis)** & Neg [141] \\
**Butyrolactone** & & \\
**Cprb/SCO671 (\(\gamma\)-butyrolactone-responsive regulator)** & Neg [162; 163] \\
**SibR/SCO608 (\(\gamma\)-butyrolactone-responsive regulator)** & Neg [113] \\
**SchA/SCO6266 (gamma-butyrolactone synthesis)** & Neg [56; 57] \\
**AfsR/SCO4426 (\(\gamma\)-butyrolactone-responsive regulator)** & Pos [152; 156; 157] \\
**Others** & BldD/SCO5723 (c-di-GMP signaling) & Neg [112] \\
**SCO6808** & Neg [115] \\
**SCO7128** & Neg [85] \\
**PkaF/SCO2110 (ESTPK)** & Neg [155] \\
**RpoZ/SCO1478 (omega sub-unit of RNA polymerase)** & Pos [209] \\
**Odds/**Ods/**SCO2004/SCO0203 (TCS dormancy/survival regulon)** & Pos [91] \\
**Cprb/SCO371 (Cyclic AMP receptor protein)** & Pos [82] \\
**Arta/SCO4118** & Pos [84] \\
**ArbC3/SCO4596 (TCS response regulator)** & Pos [71; 72; 73] \\ \hline \hline \end{tabular}
\end{table} 
Table 1: List of the 71 transcriptional regulators and 23 eukaryotic-like protein kinases detected in our study and classified, when possible, according to their role in the regulation of phosphate and/or nitrogen up-take and assimilation (6), in cell wall (5), osmotic (8), and oxidative (5) stress responses, in metal homeostasis (6), butylrolactone response (4), and others processes (38). Regulators are either known to have a positive (Pos) or negative (Neg) impact on ACT biosynthesis or a predictable one (Neg or Pos within brackets followed by a question mark) or an unknown one (question mark). Regulators in black are those that were more abundant in SC than in _SL_, whereas regulators in red are those that were more abundant in _SL_ than in _SC_. The numbers within brackets are referring to publications demonstrating the positive or negative regulatory role played by each transcriptional regulator in the regulation of ACT biosynthesis. Regulators in bold are those that were shown to interact directly with the promoter region of actII-ORF4 which encodes the specific activator of the ACT cluster. (SigB/SCO600) is within brackets since it is known to be involved in osmotic stress response and to have impact on ACT biosynthesis, but it was not detected in our study.