Pseudomonas putida KT2440

A certified safety-strain soil bacterium with exceptional solvent/stress tolerance and diverse metabolism. The premier chassis for environmental biosensing of pollutants and heavy metals in soil and water.

BSL-1

Identity

Species
Pseudomonas putida
Strain
KT2440
NCBI taxid
160488
Genome
NC_002947.4

Safety

Biosafety level
BSL-1
Pathogenic
No
GRAS
No
Biocontainment
Well-developed containment circuits; the first Gram-negative soil bacterium certified as a safe cloning host (HV1).
BSL-1 basis
ABSA Risk Group 1; KT2440 is a certified host-vector biosafety (HV1) strain (US Federal Register, 1982).

Rifampicin-resistant plasmid-cured derivative of P. putida mt-2; metabolically versatile, robust outdoors.

Traits

Gram
negative
Oxygen
aerobe
Optimal temp
30 °C
Doubling time
~40 min
Spore-forming
No
Transformable
Yes

Engineering

CRISPR tooling
dCas9/CRISPRi and CRISPR base-editing established in P. putida.
Common promoters
Pm/XylS, Pu, lac-derived, Anderson series
Selection markers
KanR, GmR, TcR
Toolkits
SEVA (Standard European Vector Architecture), Marburg Collection-style parts

Biosensors using this chassis

Alkane/oil sensor (AlkS + CRISPRa)

Detects medium-chain alkanes (diesel / crude-oil contamination). The AlkS regulator gates a CRISPRa circuit driving a fluorescent reporter, in the solvent-tolerant chassis P. putida KT2440.

environmentalCRISPRa-activation

Benzoate sensor (BenM + CRISPRi)

Detects benzoate, a common aromatic pollutant and degradation intermediate. The BenM LysR-family regulator gates a CRISPRi circuit driving a visible pigment, in P. putida KT2440.

environmentalCRISPRi-repression

Copper soil sensor (CueR + CRISPRi)

Detects bioavailable copper Cu(I)/Cu(II) in soil and water. The CueR copper-responsive regulator gates a CRISPRi circuit driving a visible chromoprotein, in the robust environmental chassis P. putida KT2440.

environmentalCRISPRi-repression

Crown-gall sensor (TraR/3OC8-HSL + CRISPRi)

Detects the plant pathogen Agrobacterium tumefaciens via its 3-oxo-C8-HSL quorum signal. The TraR receptor gates a CRISPRi circuit driving a visible pigment, in the soil chassis P. putida KT2440 — for agricultural crown-gall surveillance.

pathogenCRISPRi-repression

Cuminate sensor (CymR + CRISPRa)

Detects cuminate (p-isopropylbenzoate), a terpenoid-degradation marker. The native P. putida CymR sensor gates a CRISPRa circuit driving a fluorescent reporter, in P. putida KT2440.

chemicalCRISPRa-activation

DAPG biocontrol sensor (PhlF + CRISPRi)

Detects 2,4-diacetylphloroglucinol (DAPG), an antibiotic made by biocontrol pseudomonads in soil. The Marionette PhlF sensor gates a CRISPRi circuit driving a visible pigment, in the soil chassis P. putida KT2440 — useful for monitoring soil biocontrol activity.

chemicalCRISPRi-repression

Iron sensor (Fur + CRISPRi)

Reports bioavailable iron via the Fur ferric-uptake regulator, gating a CRISPRi circuit driving a fluorescent reporter, in the robust environmental chassis P. putida KT2440. Useful for soil/water iron and process monitoring.

chemicalCRISPRi-repression

Mercury soil/water sensor (MerR + CRISPRi)

Detects ionic mercury Hg(II) in soil and water. The MerR/PmerT sensing module gates a CRISPRi circuit driving a visible chromoprotein, in the rugged environmental chassis P. putida KT2440.

environmentalCRISPRa-activation

P. aeruginosa sensor (PQS/PqsR + CRISPRi)

Detects Pseudomonas aeruginosa via its quinolone signal (PQS). The PqsR (MvfR) receptor gates a CRISPRi circuit driving a visible pigment, in the safe Pseudomonas relative P. putida KT2440.

pathogenCRISPRi-repression

Phenol sensor (DmpR + CRISPRa)

Detects phenol and methylphenols in water/soil. The DmpR aromatic sensor gates a CRISPRa circuit driving a fluorescent reporter, in the phenol-tolerant chassis P. putida KT2440.

environmentalCRISPRa-activation

Toluene/BTEX sensor (XylR + CRISPRi)

Detects toluene and related BTEX aromatic pollutants. The native XylR/Pu regulator gates a CRISPRi circuit driving a visible pigment, in P. putida KT2440 — a natural toluene-degrader and rugged environmental chassis.

environmentalCRISPRi-repression