Growth of genetically-engineered Pseudomonas aeruginosa and Pseudomonas putida in soil and rhizosphere

The biodegradation of phenol and chlorophenols by immobilized pure-culture cells was conducted by a series of batch reactors. The microorganisms used in this study were Pseudomonas putida, Psuedomonas testosteroni, Pseudomonas aeruginosa, and Agrobacterium radiobacter. All four species showed the ortho-cleavage pathway to metabolize chlorophenols. Among the four species, P. testosteroni, P. putida, and P. aeruginosa could effectively remove phenol at 200 mg/l. P. testosteroni could effectively remove 2-chlorophenol at 10mg/l. However, the other three species, P. putida, P. aeruginosa, and A. radiobacter, could not effectively remove 2-chlorophenol. Although 3-chlorophenol is a recalcitrant compound, P. testosteroni also could rapidly metabolize 3-chlorophenol at 10 mg/l. The removal of 4-chlorophenol at 10 mg/l by P. testosteroni reached 98% within one day. P. aeruginosa and A. radiobacter also could metabolize 4-chlorophenol after 2 and 7 days of lag period, respectively.

Download Full-text

High‐throughput dilution‐based growth method enables time‐resolved exo‐metabolomics of Pseudomonas putida and Pseudomonas aeruginosa

Microbial Biotechnology ◽

10.1111/1751-7915.13905 ◽

2021 ◽

Author(s):

Bjarke H. Pedersen ◽

Nicolás Gurdo ◽

Helle Krogh Johansen ◽

Søren Molin ◽

Pablo I. Nikel ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Pseudomonas Putida ◽

High Throughput ◽

Time Resolved ◽

Growth Method

Download Full-text

Conjugal TOL Transfer from Pseudomonas putida to Pseudomonas aeruginosa: Effects of Restriction Proficiency, Toxicant Exposure, Cell Density Ratios, and Conjugation Detection Method on Observed Transfer Efficiencies

Applied and Environmental Microbiology ◽

10.1128/aem.71.1.51-57.2005 ◽

2005 ◽

Vol 71 (1) ◽

pp. 51-57 ◽

Cited By ~ 34

Author(s):

Catalina Arango Pinedo ◽

Barth F. Smets

Keyword(s):

Pseudomonas Aeruginosa ◽

Pseudomonas Putida ◽

Strong Dependence ◽

Plasmid Transfer ◽

Mass Action ◽

Tol Plasmid ◽

Toxicant Exposure ◽

Transfer Frequency ◽

Cell Densities

ABSTRACT The effects of restriction proficiency and premating exposure to toxicants on conjugal transfer of the TOL plasmid between Pseudomonas spp. was investigated by examinations of filter matings. A Pseudomonas putida KT2442-derived strain carrying a gfp-tagged variant of the TOL plasmid was used as a donor, and both restriction-deficient (PAO1162N) and -proficient (PAO2002N) Pseudomonas aeruginosa strains were used as recipients. The in situ enumeration of conjugation events allowed us to obtain frequency estimates that were unbiased by transconjugant growth or plasmid retransfer. We observed a strong dependence of the plasmid transfer frequency on the initial donor-to-recipient ratio of surface matings, which invalidated the use of mass action-based plasmid transfer kinetic estimators. Careful control of the initial parental cell densities permitted evaluations of the true effects of restriction proficiency and toxicant exposure on TOL transfer. At standard donor-to-recipient ratios (10−3 for PAO1162N and 2 Ã¯Â¿Â½ 101 for PAO2002N) and total cell densities (105 cells/mm2 for PAO1162N and 106 cells/mm2 for PAO2002N), plasmid transfer frequencies without toxicant exposure were approximately 10−7 (events/mm2)−1 for PAO1162N and 10−11 (events/mm2)−1 for PAO2002N based on in situ observations of conjugation events. The enumeration of transconjugants via selective plating yielded transfer frequencies that were up to 1 order of magnitude lower. Premating exposure to sodium dodecyl sulfate (1 to 10 mM) significantly increased the transfer frequency for the restriction-proficient strain PAO2002N (P < 0.05) but not for the restriction-deficient strain PAO1162N. On the other hand, premating exposure to ethanol, toluene, or phenol had no positive effect on the plasmid transfer frequency. Clearly, restriction proficiency provides a strong barrier to interspecific transfer of the TOL plasmid, and this barrier was only marginally attenuated by recipient exposure to toxicants within the ranges examined.

Download Full-text

Use of ureidopenicillins for selection of plasmid vector transformants in Pseudomonas aeruginosa and Pseudomonas putida.

Journal of Bacteriology ◽

10.1128/jb.157.3.937-939.1984 ◽

1984 ◽

Vol 157 (3) ◽

pp. 937-939 ◽

Cited By ~ 4

Author(s):

D L Day ◽

D Yasinow ◽

J McDonough ◽

C W Shuster

Keyword(s):

Pseudomonas Aeruginosa ◽

Pseudomonas Putida ◽

Plasmid Vector ◽

Selection Of

Download Full-text

nalD Encodes a Second Repressor of the mexAB-oprM Multidrug Efflux Operon of Pseudomonas aeruginosa

Journal of Bacteriology ◽

10.1128/jb.01342-06 ◽

2006 ◽

Vol 188 (24) ◽

pp. 8649-8654 ◽

Cited By ~ 50

Author(s):

Yuji Morita ◽

Lily Cao ◽

Virginia C. Gould ◽

Matthew B. Avison ◽

Keith Poole

Keyword(s):

Pseudomonas Aeruginosa ◽

Pseudomonas Putida ◽

Stenotrophomonas Maltophilia ◽

Multidrug Efflux ◽

Efflux System

ABSTRACT The Pseudomonas aeruginosa nalD gene encodes a TetR family repressor with homology to the SmeT and TtgR repressors of the smeDEF and ttgABC multidrug efflux systems of Stenotrophomonas maltophilia and Pseudomonas putida, respectively. A sequence upstream of mexAB-oprM and overlapping a second promoter for this efflux system was very similar to the SmeT and TtgR operator sequences, and NalD binding to this region was, in fact, demonstrated. Moreover, increased expression from this promoter was seen in a nalD mutant, consistent with NalD directly controlling mexAB-oprM expression from a second promoter.

Download Full-text

Hierarchical management of carbon sources is regulated similarly by the CbrA/B systems in Pseudomonas aeruginosa and Pseudomonas putida

Microbiology ◽

10.1099/mic.0.078873-0 ◽

2014 ◽

Vol 160 (10) ◽

pp. 2243-2252 ◽

Cited By ~ 31

Author(s):

Martina Valentini ◽

Sofía M. García-Mauriño ◽

Isabel Pérez-Martínez ◽

Eduardo Santero ◽

Inés Canosa ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Pseudomonas Putida ◽

Nitrogen Availability ◽

Carbon Sources ◽

Signal Transduction Pathway ◽

Exact Nature ◽

Energy Status ◽

Regulatory Systems ◽

Close Relationship ◽

Carbon Nitrogen Ratio

The CbrA/B system in pseudomonads is involved in the utilization of carbon sources and carbon catabolite repression (CCR) through the activation of the small RNAs crcZ in Pseudomonas aeruginosa, and crcZ and crcY in Pseudomonas putida. Interestingly, previous works reported that the CbrA/B system activity in P. aeruginosa PAO1 and P. putida KT2442 responded differently to the presence of different carbon sources, thus raising the question of the exact nature of the signal(s) detected by CbrA. Here, we demonstrated that the CbrA/B/CrcZ(Y) signal transduction pathway is similarly activated in the two Pseudomonas species. We show that the CbrA sensor kinase is fully interchangeable between the two species and, moreover, responds similarly to the presence of different carbon sources. In addition, a metabolomics analysis supported the hypothesis that CCR responds to the internal energy status of the cell, as the internal carbon/nitrogen ratio seems to determine CCR and non-CCR conditions. The strong difference found in the 2-oxoglutarate/glutamine ratio between CCR and non-CCR conditions points to the close relationship between carbon and nitrogen availability, or the relationship between the CbrA/B and NtrB/C systems, suggesting that both regulatory systems sense the same sort or interrelated signal.

Download Full-text