Control of Morphological Differentiation of Streptomyces coelicolor A3(2) by Phosphorylation of MreC and PBP2.
During morphological differentiation of Streptomyces coelicolor A3(2), the sporogenic aerial hyphae are transformed into a chain of more than fifty spores in a highly coordinated manner. Synthesis of the thickened spore envelope is directed by the Streptomyces spore wall synthesizing complex SSSC which resembles the elongasome of rod-shaped bacteria. The SSSC includes the eukaryotic type serine/threonine protein kinase (eSTPK) PkaI, encoded within a cluster of five independently transcribed eSTPK genes (SCO4775-4779). To understand the role of PkaI in spore wall synthesis, we screened a S. coelicolor genomic library for PkaI interaction partners by bacterial two-hybrid analyses and identified several proteins with a documented role in sporulation. We inactivated pkaI and deleted the complete SCO4775-4779 cluster. Deletion of pkaI alone delayed sporulation and produced some aberrant spores. The five-fold mutant NLΔ4775-4779 had a more severe defect and produced 18% aberrant spores affected in the integrity of the spore envelope. Moreover, overbalancing phosphorylation activity by expressing a second copy of any of these kinases caused a similar defect. Following co-expression of pkaI with either mreC or pbp2 in E. coli, phosphorylation of MreC and PBP2 was demonstrated and multiple phosphosites were identified by LC-MS/MS. Our data suggest that elaborate protein phosphorylation controls activity of the SSSC to ensure proper sporulation by suppressing premature cross-wall synthesis.
Interfakultaeres Institut für Mikrobiologie und Infektionsmedizin Tuebingen IMIT, Mikrobiologie/Biotechnologie, Eberhard Karls Universitaet Tuebingen, Auf der Morgenstelle 28, 72076 Tuebingen, Germany.
Nils
N
Ladwig
Proteome Center Tuebingen, Interfakultaeres Institut für Zellbiologie, Eberhard Karls Universitaet Tuebingen, Auf der Morgenstelle 15,72076 Tübingen, Germany.
Mirita
M
Franz-Wachtel
Interfakultaeres Institut für Mikrobiologie und Infektionsmedizin Tuebingen IMIT, Mikrobiologie/Biotechnologie, Eberhard Karls Universitaet Tuebingen, Auf der Morgenstelle 28, 72076 Tuebingen, Germany.
Felix
F
Hezel
Proteome Center Tuebingen, Interfakultaeres Institut für Zellbiologie, Eberhard Karls Universitaet Tuebingen, Auf der Morgenstelle 15,72076 Tübingen, Germany.
Boumediene
B
Soufi
Proteome Center Tuebingen, Interfakultaeres Institut für Zellbiologie, Eberhard Karls Universitaet Tuebingen, Auf der Morgenstelle 15,72076 Tübingen, Germany.
Boris
B
Macek
Interfakultaeres Institut für Mikrobiologie und Infektionsmedizin Tuebingen IMIT, Mikrobiologie/Biotechnologie, Eberhard Karls Universitaet Tuebingen, Auf der Morgenstelle 28, 72076 Tuebingen, Germany.
Wolfgang
W
Wohlleben
Interfakultaeres Institut für Mikrobiologie und Infektionsmedizin Tuebingen IMIT, Mikrobiologie/Biotechnologie, Eberhard Karls Universitaet Tuebingen, Auf der Morgenstelle 28, 72076 Tuebingen, Germany.
Günther
G
Muth
D001426:Bacterial Proteins / Q000378:metabolism*; D004926:Escherichia coli / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D046915:Penicillin-Binding Proteins / Q000378:metabolism; D010766:Phosphorylation; D011485:Protein Binding; D013171:Spores, Bacterial / Q000378:metabolism; D048372:Streptomyces coelicolor / Q000166:cytology* / Q000378:metabolism*; D053719:Tandem Mass Spectrometry
D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; C062061:MreC protein, Bacteria; D046915:Penicillin-Binding Proteins; C582982:MrdA protein, E coli