RT Journal Article
T1 HsbA represses stationary phase biofilm formation in Pseudomonas putida
A1 Pulido Sánchez, Marta
A1 Montero Beltrán, Elisa
A1 López Sánchez, Aroa
A1 Govantes, Fernando
K1 Biofilm
K1 Cyclic di-GMP
K1 Pseudomonas
K1 Signal transduction
K1 Stationary phase
K1 Stress responses
AB Pseudomonas putida biofilm growth is associated to nutrient-sufficient conditions and biofilm dispersal is induced by nutrient starvation, signaled by the stringent response-associated nucleotide alarmone (p)ppGpp. We have used transcriptomic analysis to show that (p)ppGpp regulates the hsbAR-hptB gene cluster, encoding components of a phosphorelay pathway and an anti-σ factor antagonist, and cfcR, encoding a response regulator with diguanylate cyclase (DGC) activity. Transcription of hsbAR-hptB and cfcR is RpoS-dependent and induced by stationary phase and the stringent response. A ∆hsbA mutant resumed biofilm formation after dispersal in late stationary phase and displayed increased pellicle formation at the medium-air interphase and Congo Red adsorption. All these phenotypes were traced down to increased c-di-GMP levels in stationary phase, dependent on the activity of CfcR and its cognate sensor kinase, CfcA. HsbA was reversibly phosphorylated by the combined action of HptB and HsbR. HsbA phosphorylation conditioned its interaction with CfcR and CfcA and the subcellular distribution of the three proteins. In spite of this, HsbA retained its ability to prevent biofilm formation regardless of its phosphorylation state. Our results support a model in which HsbA forms a complex with CfcR to inhibit its DGC activity regardless of its phosphorylation state. Upon HsbA dephosphorylation, this complex is recruited to the cell membrane by CfcA to strengthen the inhibitory effect. While this pathway contributes to biofilm dispersal by denying de novo c-di-GMP synthesis during nutrient starvation, it may also enable quick restoration of the biofilm phenotype to colonize new sites or during biofilm maturation.
PB Elsevier
YR 2025
FD 2025-12-19
LK https://hdl.handle.net/10433/25541
UL https://hdl.handle.net/10433/25541
LA en
NO Microbiological Research Volume 305, April 2026, 128428
NO Proyectos de investigaciónPGC2018–097151-B-I00PID2021–126121-NB-I00CEX2020–00108-M
NO Universidad Pablo de Olavide. Departamento de Biología Molecular e Ingeniería Bioquímica
NO Centro Andaluz de Biología del Desarrollo
DS RIO
RD Apr 27, 2026