TY - JOUR
T1 - Processing of cell-surface signalling anti-sigma factors prior to signal recognition is aconserved autoproteolytic mechanism that produces two functional domains.
AU - Bastiaansen, K.C.J.T.
AU - Otero-Asman, J.R.
AU - Luirink, J.
AU - Bitter, W.
AU - Llamas, M.A.
PY - 2015
Y1 - 2015
N2 - Cell-surface signalling (CSS) enables Gram-negative bacteria to transduce an environmental signal into a cytosolic response. This regulatory cascade involves an outer membrane receptor that transmits the signal to an anti-sigma factor in the cytoplasmic membrane, allowing the activation of an extracytoplasmic function (ECF) sigma factor. Recent studies have demonstrated that RseP-mediated proteolysis of the anti-sigma factors is key to σECF activation. Using the Pseudomonas aeruginosaFoxR anti-sigma factor, we show here that RseP is responsible for the generation of an N-terminal tail that likely contains pro-sigma activity. Furthermore, it has been reported previously that this anti-sigma factor is processed in two separate domains prior to signal recognition. Here, we demonstrate that this process is common in these types of proteins and that the processing event is probably due to autoproteolytic activity. The resulting domains interact and function together to transduce the CSS signal. However, our results also indicate that this processing event is not essential for activity. In fact, we have identified functional CSS anti-sigma factors that are not cleaved prior to signal perception. Together, our results indicate that CSS regulation can occur through both complete and initially processed anti-sigma factors.
AB - Cell-surface signalling (CSS) enables Gram-negative bacteria to transduce an environmental signal into a cytosolic response. This regulatory cascade involves an outer membrane receptor that transmits the signal to an anti-sigma factor in the cytoplasmic membrane, allowing the activation of an extracytoplasmic function (ECF) sigma factor. Recent studies have demonstrated that RseP-mediated proteolysis of the anti-sigma factors is key to σECF activation. Using the Pseudomonas aeruginosaFoxR anti-sigma factor, we show here that RseP is responsible for the generation of an N-terminal tail that likely contains pro-sigma activity. Furthermore, it has been reported previously that this anti-sigma factor is processed in two separate domains prior to signal recognition. Here, we demonstrate that this process is common in these types of proteins and that the processing event is probably due to autoproteolytic activity. The resulting domains interact and function together to transduce the CSS signal. However, our results also indicate that this processing event is not essential for activity. In fact, we have identified functional CSS anti-sigma factors that are not cleaved prior to signal perception. Together, our results indicate that CSS regulation can occur through both complete and initially processed anti-sigma factors.
U2 - 10.1111/1462-2920.12776
DO - 10.1111/1462-2920.12776
M3 - Article
SN - 1462-2912
VL - 17
SP - 3263
EP - 3277
JO - Environmental Microbiology
JF - Environmental Microbiology
IS - 9
ER -