Correction: Mucosal fluid glycoprotein DMBT1 suppresses twitching motility and virulence of the opportunistic pathogen Pseudomonas aeruginosa

ABSTRACT The opportunistic pathogen Pseudomonas aeruginosa expresses polar type IV pili (TFP), which are responsible for adhesion to various materials and twitching motility on surfaces. Twitching occurs by alternate extension and retraction of TFP, which arise from assembly and disassembly of pilin subunits at the base of the pilus. The ATPase PilB promotes pilin assembly, while the ATPase PilT or PilU or both promote pilin dissociation. Fluorescent fusions to two of the three ATPases (PilT and PilU) were functional, as shown by complementation of the corresponding mutants. PilB and PilT fusions localized to both poles, while PilU fusions localized only to the piliated pole. To identify the portion of the ATPases required for localization, sequential C-terminal deletions of PilT and PilU were generated. The conserved His and Walker B boxes were dispensable for polar localization but were required for twitching motility, showing that localization and function could be uncoupled. Truncated fusions that retained polar localization maintained their distinctive distribution patterns. To dissect the cellular factors involved in establishing polarity, fusion protein localization was monitored with a panel of TFP mutants. The localization of yellow fluorescent protein (YFP)-PilT and YFP-PilU was independent of the subunit PilA, other TFP ATPases, and TFP-associated proteins previously shown to be associated with the membrane or exhibiting polar localization. In contrast, YFP-PilB exhibited diffuse cytoplasmic localization in a pilC mutant, suggesting that PilC is required for polar localization of PilB. Finally, localization studies performed with fluorescent ATPase chimeras of PilT and PilU demonstrated that information responsible for the characteristic localization patterns of the ATPases likely resides in their N termini.

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Cyclic AMP-Independent Control of Twitching Motility in Pseudomonas aeruginosa

Journal of Bacteriology ◽

10.1128/jb.00188-17 ◽

2017 ◽

Vol 199 (16) ◽

Cited By ~ 13

Author(s):

Ryan N. C. Buensuceso ◽

Martin Daniel-Ivad ◽

Sara L. N. Kilmury ◽

Tiffany L. Leighton ◽

Hanjeong Harvey ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Cyclic Amp ◽

Response Regulator ◽

Opportunistic Pathogen ◽

Regulatory Elements ◽

Twitching Motility ◽

Camp Phosphodiesterase ◽

Content Type ◽

Polar Localization ◽

Camp Levels

ABSTRACT FimV is a Pseudomonas aeruginosa inner membrane hub protein that modulates levels of the second messenger, cyclic AMP (cAMP), through the activation of adenylate cyclase CyaB. Although type IVa pilus (T4aP)-dependent twitching motility is modulated by cAMP levels, mutants lacking FimV are twitching impaired, even when exogenous cAMP is provided. Here we further define FimV's cAMP-dependent and -independent regulation of twitching. We confirmed that the response regulator of the T4aP-associated Chp chemotaxis system, PilG, requires both FimV and the CyaB regulator, FimL, to activate CyaB. However, in cAMP-replete backgrounds—lacking the cAMP phosphodiesterase CpdA or the CheY-like protein PilH or expressing constitutively active CyaB—pilG and fimV mutants failed to twitch. Both cytoplasmic and periplasmic domains of FimV were important for its cAMP-dependent and -independent roles, while its septal peptidoglycan-targeting LysM motif was required only for twitching motility. Polar localization of the sensor kinase PilS, a key regulator of transcription of the major pilin, was FimV dependent. However, unlike its homologues in other species that localize flagellar system components, FimV was not required for swimming motility. These data provide further evidence to support FimV's role as a key hub protein that coordinates the polar localization and function of multiple structural and regulatory proteins involved in P. aeruginosa twitching motility. IMPORTANCE Pseudomonas aeruginosa is a serious opportunistic pathogen. Type IVa pili (T4aP) are important for its virulence, because they mediate dissemination and invasion via twitching motility and are involved in surface sensing, which modulates pathogenicity via changes in cAMP levels. Here we show that the hub protein FimV and the response regulator of the Chp system, PilG, regulate twitching independently of their roles in the modulation of cAMP synthesis. These functions do not require the putative scaffold protein FimL, proposed to link PilG with FimV. PilG may regulate asymmetric functioning of the T4aP system to allow for directional movement, while FimV appears to localize both structural and regulatory elements—including the PilSR two-component system—to cell poles for optimal function.

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Mechanotaxis directs Pseudomonas aeruginosa twitching motility

10.1101/2021.01.26.428277 ◽

2021 ◽

Author(s):

Marco J. Kühn ◽

Lorenzo Talà ◽

Yuki Inclan ◽

Ramiro Patino ◽

Xavier Pierrat ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Single Cells ◽

Opportunistic Pathogen ◽

Type Iv Pili ◽

Twitching Motility ◽

Response Regulators ◽

Spatially Resolved ◽

Type Iv ◽

Mechanical Signal ◽

Chp System

AbstractThe opportunistic pathogen Pseudomonas aeruginosa explores surfaces using twitching motility powered by retractile extracellular filaments called type IV pili. Single cells twitch by successive pili extension, attachment and retraction. However, whether and how single cells control twitching migration remains unclear. We discovered that P. aeruginosa actively directs twitching in the direction of mechanical input from type IV pili, in a process we call mechanotaxis. The Chp chemotaxis-like system controls the balance of forward and reverse twitching migration of single cells in response to the mechanical signal. On surfaces, Chp senses type IV pili attachment at one pole thereby sensing a spatially-resolved signal. As a result, the Chp response regulators PilG and PilH control the polarization of the extension motor PilB. PilG stimulates polarization favoring forward migration, while PilH inhibits polarization inducing reversal. Subcellular segregation of PilG and PilH efficiently orchestrates their antagonistic functions, ultimately enabling rapid reversals upon perturbations. This distinct localization of response regulators establishes a signaling landscape known as local-excitation, global-inhibition in higher order organisms, identifying a conserved strategy to transduce spatially-resolved signals. Our discovery finally resolves the function of the Chp system and expands our view of the signals regulating motility.

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Mucosal fluid glycoprotein DMBT1 suppresses twitching motility and virulence of the opportunistic pathogen Pseudomonas aeruginosa

PLoS Pathogens ◽

10.1371/journal.ppat.1006392 ◽

2017 ◽

Vol 13 (5) ◽

pp. e1006392 ◽

Cited By ~ 10

Author(s):

Jianfang Li ◽

Matteo M. E. Metruccio ◽

David J. Evans ◽

Suzanne M. J. Fleiszig

Keyword(s):

Pseudomonas Aeruginosa ◽

Opportunistic Pathogen ◽

Twitching Motility

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Suicidal chemotaxis in bacteria

10.1101/2021.12.21.473623 ◽

2021 ◽

Author(s):

Nuno M Oliveira ◽

James H R Wheeler ◽

Cyril Deroy ◽

Sean C Booth ◽

Edmond J Walsh ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Inhibitory Concentration ◽

Microfluidic Devices ◽

Chemical Compounds ◽

Opportunistic Pathogen ◽

Twitching Motility ◽

Direct Response ◽

Spatial Gradients ◽

Migrating Cells

Bacteria commonly live in communities on surfaces where steep gradients of antibiotics and other chemical compounds routinely occur. While many species of bacteria can move on surfaces, we know surprisingly little about how such antibiotic gradients affect cell motility. Here we study the behaviour of the opportunistic pathogen Pseudomonas aeruginosa in stable spatial gradients of a range of antibiotics by tracking thousands of cells in microfluidic devices as they form biofilms. Unexpectedly, these experiments reveal that individual bacteria use pili-based ('twitching') motility to actively navigate towards regions with higher antibiotic concentrations. Our analyses suggest that this biased migration is driven, at least in part, by a direct response to the antibiotics. Migrating cells can reach antibiotic concentrations hundreds of times higher than their minimum inhibitory concentration in a few hours and remain highly motile. However, isolating these cells - using fluid-walled microfluidic devices that can be reconfigured in situ - suggests that these bacteria are terminal and not able to reproduce. In spite of moving towards their death, we show that migrating cells are capable of entering a suicidal program to release bacteriocins that are used to kill other bacteria. Our work suggests that bacteria respond to antibiotics as if they come from a competing colony growing in the neighbourhood, inducing them to invade and attack. As a result, clinical antibiotics have the potential to serve as a bait that lures bacteria to their death.

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Mechanotaxis directs Pseudomonas aeruginosa twitching motility

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2101759118 ◽

2021 ◽

Vol 118 (30) ◽

pp. e2101759118

Author(s):

Marco J. Kühn ◽

Lorenzo Talà ◽

Yuki F. Inclan ◽

Ramiro Patino ◽

Xavier Pierrat ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Single Cells ◽

Opportunistic Pathogen ◽

Group Behavior ◽

Twitching Motility ◽

Response Regulators ◽

Spatially Resolved ◽

Type Iv ◽

Mechanical Signal ◽

Global Inhibition

The opportunistic pathogen Pseudomonas aeruginosa explores surfaces using twitching motility powered by retractile extracellular filaments called type IV pili (T4P). Single cells twitch by sequential T4P extension, attachment, and retraction. How single cells coordinate T4P to efficiently navigate surfaces remains unclear. We demonstrate that P. aeruginosa actively directs twitching in the direction of mechanical input from T4P in a process called mechanotaxis. The Chp chemotaxis-like system controls the balance of forward and reverse twitching migration of single cells in response to the mechanical signal. Collisions between twitching cells stimulate reversals, but Chp mutants either always or never reverse. As a result, while wild-type cells colonize surfaces uniformly, collision-blind Chp mutants jam, demonstrating a function for mechanosensing in regulating group behavior. On surfaces, Chp senses T4P attachment at one pole, thereby sensing a spatially resolved signal. As a result, the Chp response regulators PilG and PilH control the polarization of the extension motor PilB. PilG stimulates polarization favoring forward migration, while PilH inhibits polarization, inducing reversal. Subcellular segregation of PilG and PilH efficiently orchestrates their antagonistic functions, ultimately enabling rapid reversals upon perturbations. The distinct localization of response regulators establishes a signaling landscape known as local excitation–global inhibition in higher-order organisms, identifying a conserved strategy to transduce spatially resolved signals.

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cAMP-independent control of twitching motility inPseudomonas aeruginosa

10.1101/116954 ◽

2017 ◽

Author(s):

Ryan N.C. Buensuceso ◽

Martin Daniel-Ivad ◽

Sara L.N. Kilmury ◽

Hanjeong Harvey ◽

P. Lynne Howell ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Response Regulator ◽

Opportunistic Pathogen ◽

Regulatory Elements ◽

Twitching Motility ◽

Camp Phosphodiesterase ◽

Polar Localization ◽

And Function ◽

Chemotaxis System ◽

Camp Levels

ABSTRACTFimV is aPseudomonas aeruginosainner membrane hub protein that modulates levels of the second messenger, cyclic AMP (cAMP), through activation of the adenylate cyclase, CyaB. Although type IVa pilus (T4aP)-dependent twitching motility is modulated by cAMP levels, mutants lacking FimV are twitching impaired, even when exogenous cAMP is provided. Here we further define FimV’s cAMP-dependent and -independent regulation of twitching. We confirmed that the response regulator of the T4aP-associated Chp chemotaxis system, PilG, required both FimV and the CyaB regulator, FimL, to activate CyaB. However, in cAMP-replete backgrounds - lacking the cAMP phosphodiesterase CpdA or the CheY-like protein PilH, or expressing constitutively-active CyaB -pilGandfimVmutants failed to twitch. Both cytoplasmic and periplasmic domains of FimV were important for its cAMP-dependent and -independent roles, while its septal peptidoglycan-targeting LysM motif was required only for twitching motility. Polar localization of the sensor kinase PilS, a key regulator of transcription of the major pilin, was FimV-dependent. However, unlike its homologues in other species that localize flagellar system components, FimV was not required for swimming motility. These data provide further evidence to support FimV’s role as a key hub protein that coordinates the polar localization and function of multiple structural and regulatory proteins involved inP. aeruginosatwitching motility.IMPORTANCEPseudomonas aeruginosais a serious opportunistic pathogen. Type IVa pili (T4aP) are important for its virulence, because they mediate dissemination and invasion via twitching motility, and are involved in surface sensing which modulates pathogenicity via changes in cAMP levels. Here we show that the hub protein FimV and the response regulator of the Chp system, PilG, regulate twitching independently of their roles in modulation of cAMP synthesis. These functions do not require the putative scaffold protein FimL, proposed to link PilG with FimV. PilG may regulate asymmetric functioning of the T4aP system to allow for directional movement, while FimV appears to localize both structural and regulatory elements – including the PilSR two-component system – to cell poles for optimal function.

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The In Vitro Antibiofilm Activity of Water Leaf Extract of Papaya (Carica papaya L.) against Pseudomonas aeruginosa

Current Biochemistry ◽

10.29244/cb.2.3.150-163 ◽

2017 ◽

Vol 2 (3) ◽

pp. 150-163

Author(s):

Ekajayanti Kining ◽

Syamsul Falah ◽

Novik Nurhidayat

Keyword(s):

Pseudomonas Aeruginosa ◽

Contact Time ◽

Cell Attachment ◽

Water Extract ◽

Opportunistic Pathogen ◽

Bacterial Biofilm ◽

Antibiofilm Activity ◽

Bacterial Survival ◽

Optimum Conditions

Pseudomonas aeruginosa is one of opportunistic pathogen forming bacterial biofilm. The biofilm sustains the bacterial survival and infections. This study aimed to assess the activity of water extract of papaya leaves on inhibition of cells attachment, growth and degradation of the biofilm using crystal violet (CV) biofilm assay. Research results showed that water extract of papaya leaves contains alkaloids, tanins, flavonoids, and steroids/terpenoids and showed antibacterial activity and antibiofilm against P. aeruginosa. Addition of extract can inhibit the cell attachment and was able to degrade the biofilm of 40.92% and 48.058% respectively at optimum conditions: extract concentration of 25% (v/v), temperature 37.5 °C and contact time 45 minutes. With a concentration of 25% (v/v), temperature of 50 °C and the contact time of 3 days, extract of papaya leaves can inhibit the growth of biofilms of 39.837% v/v.

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Faculty Opinions recommendation of FimX, a multidomain protein connecting environmental signals to twitching motility in Pseudomonas aeruginosa.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1018586.208574 ◽

2004 ◽

Author(s):

Fergal O'Gara

Keyword(s):

Pseudomonas Aeruginosa ◽

Twitching Motility ◽

Environmental Signals ◽

Multidomain Protein

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Prevalence of metallo-β-lactamase genes among Pseudomonas aeruginosa isolated from various clinical samples in China

Journal of Laboratory Medicine ◽

10.1515/labmed-2019-0162 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Wei Wang ◽

Xiaoya Wang

Keyword(s):

Pseudomonas Aeruginosa ◽

Antibiotic Susceptibility ◽

Ethylenediaminetetraacetic Acid ◽

Carbapenem Resistance ◽

Opportunistic Pathogen ◽

Detection Methods ◽

Clinical Samples ◽

Routine Practice ◽

Carbapenem Resistant ◽

High Prevalence

AbstractBackgroundPseudomonas aeruginosa is an opportunistic pathogen which is associated with nosocomial infections and causes various diseases including urinary tract infection, pneumonia, soft-tissue infection and sepsis. The emergence of P. aeruginosa-acquired metallo-β-lactamase (MBL) is most worrisome and poses a serious threat during treatment and infection control. The objective of this study was to identify antibiotic susceptibility, phenotypic detection of MBL production and to determine the prevalence of MBL genes in carbapenem-resistant P. aeruginosa isolated from different clinical samples.MethodsA total of 329 non-duplicate P. aeruginosa isolated from various clinical samples from two hospitals in China between September 2017 and March 2019 were included in this study. Phenotypic detection of MBL was performed by the combined detection method using imipenem and imipenem-ethylenediaminetetraacetic acid (EDTA) discs. MBL-encoding genes including blaVIM-1, blaVIM-2, blaIMP-1, blaIMP-2, blaSPM-1, blaSIM, blaNDM-1 and blaGIM were detected by polymerase chain reaction (PCR).ResultsOf the 329 P. aeruginosa, majority of the isolates were resistant to imipenem (77.5%) followed by meropenem (64.7%). Of the 270 P. aeruginosa isolates tested, 149 (55.2%) isolates were found to be positive for MBL detection. Of the different samples, 57.8% (n = 26) of P. aeruginosa isolated from blood were found to be positive for MBL production. Of the various MBL genes, blaIMP-1 (28.2%) was the most predominant gene detected followed by blaVIM-2 (18.8%), blaVIM-1 (16.1%), blaNDM-1 (9.4%), blaIMP-2 (6.7%), blaSIM (6.0%), blaSPM-1 (4.0%) and blaGIM (1.3%) genes.ConclusionsThe high resistance of P. aeruginosa toward imipenem and meropenem and the high prevalence of blaIMP-1 and blaVIM-2 set the alarm on the increasing, perhaps the increased, carbapenem resistance. In addition to routine antibiotic susceptibility testings, our results emphasize the importance of both the phenotypic and genotypic MBL detection methods in routine practice for early detection of carbapenem resistance and to prevent further dissemination of this resistant pathogen.

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