Cyclophilin PpiB is involved in motility and biofilm formation via its functional association with certain proteins.
PpiB belongs to the superfamily of peptidyl-prolyl cis/trans isomerases (PPIases, EC: 5.2.1.8), which catalyze the rate-limiting protein folding step at peptidyl-prolyl bonds and control several biological processes. In this study, we show that PpiB acts as a negative effector of motility and biofilm formation ability of Escherichia coli. We identify multicopy suppressors of each ΔppiB phenotype among putative PpiB prey proteins which upon deletion are often characterized by analogous phenotypes. Many putative preys show similar gene expression in wild-type and ΔppiB genetic backgrounds implying possible post-translational modifications by PpiB. We further conducted in vivo and in vitro interaction screens to determine which of them represent true preys. For DnaK, acetyl-CoA carboxylase, biotin carboxylase subunit (AccC) and phosphate acetyltransferase (Pta) we also showed a direct role of PpiB in the functional control of these proteins because it increased the measured enzyme activity of each protein and further interfered with DnaK localization and the correct folding of AccC. Taken together, these results indicate that PpiB is involved in diverse regulatory mechanisms to negatively modulate motility and biofilm formation via its functional association with certain protein substrates.
Laboratory of General and Agricultural Microbiology, Faculty of Crop Science, Agricultural University of Athens, Iera Odos 75, 11855, Athens, Greece.
Aggeliki
A
Skagia
Laboratory of General and Agricultural Microbiology, Faculty of Crop Science, Agricultural University of Athens, Iera Odos 75, 11855, Athens, Greece.
Chrysoula
C
Zografou
Laboratory of General and Agricultural Microbiology, Faculty of Crop Science, Agricultural University of Athens, Iera Odos 75, 11855, Athens, Greece.
Eleni
E
Vezyri
Laboratory of General and Agricultural Microbiology, Faculty of Crop Science, Agricultural University of Athens, Iera Odos 75, 11855, Athens, Greece.
Anastasia
A
Venieraki
Laboratory of General and Agricultural Microbiology, Faculty of Crop Science, Agricultural University of Athens, Iera Odos 75, 11855, Athens, Greece.
Panagiotis
P
Katinakis
Laboratory of General and Agricultural Microbiology, Faculty of Crop Science, Agricultural University of Athens, Iera Odos 75, 11855, Athens, Greece.
Maria
M
Dimou
D000103:Acetyl-CoA Carboxylase / Q000737:chemistry* / Q000235:genetics; D018441:Biofilms / Q000254:growth & development*; D019731:Carbon-Nitrogen Ligases / Q000737:chemistry / Q000235:genetics; D021983:Cyclophilins / Q000737:chemistry / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics / Q000254:growth & development; D029968:Escherichia coli Proteins / Q000737:chemistry / Q000235:genetics*; D018840:HSP70 Heat-Shock Proteins / Q000737:chemistry / Q000235:genetics*; D010709:Phosphate Acetyltransferase / Q000235:genetics; D017510:Protein Folding
D029968:Escherichia coli Proteins; D018840:HSP70 Heat-Shock Proteins; C081786:cyclophilin B; D010709:Phosphate Acetyltransferase; C063842:dnaK protein, E coli; D021983:Cyclophilins; D019731:Carbon-Nitrogen Ligases; C019791:biotin carboxylase; D000103:Acetyl-CoA Carboxylase