Genetic basis of copper-tolerance in Australian Pseudomonas syringae pv. tomato

2019 ◽  
Vol 48 (4) ◽  
pp. 425-437
Author(s):  
Karina Griffin ◽  
P. Campbell ◽  
C. Gambley
Keyword(s):  
Pseudomonas Syringae ◽  
Genetic Basis ◽  
Copper Tolerance

Occurrence of cop-like copper resistance genes among bacteria isolated from a water distribution system

1995 ◽  
Vol 41 (7) ◽  
pp. 642-646 ◽  
Author(s):  
Chuzhao Lin ◽  
Betty H. Olson
Keyword(s):  
Pseudomonas Syringae ◽  
Resistance Genes ◽  
Distribution System ◽  
Water Distribution ◽  
Water Distribution System ◽  
Culture Media ◽  
Copper Resistance ◽  
Copper Tolerance ◽  
Resistant Bacteria ◽  
Copper Resistance Genes

The occurrence of cop-like copper resistance determinants homologous to the cop genes of Pseudomonas syringae among bacteria isolated from a water distribution system experiencing copper corrosion was investigated in this study. It was found that at least 49% of the copper-resistant bacteria and less than 15% of the copper-sensitive isolates possessed a cop homolog. The occurrence of this determinant in the copper-resistant population correlated with the degree of copper tolerance exhibited by the bacteria. The effect of organic substances present in the culture media on the empirical degree of bacterial copper tolerance is also discussed.Key words: copper resistance genes, water distribution system, cop.

scholarly journals Experimental evolution of the megaplasmid pMPPla107 in Pseudomonas stutzeri enables identification of genes contributing to sensitivity to an inhibitory agent

2021 ◽  
Vol 377 (1842) ◽  
Author(s):  
Brian A. Smith ◽  
Kevin Dougherty ◽  
Meara Clark ◽  
David A. Baltrus
Keyword(s):  
Pseudomonas Syringae ◽  
Experimental Evolution ◽  
Genetic Basis ◽  
Pseudomonas Stutzeri ◽  
Large Deletion ◽  
Host Cells ◽  
Single Amino Acid ◽  
Fitness Costs ◽  
Nonsynonymous Change ◽  
Single Amino Acid Change

Horizontally transferred elements, such as plasmids, can burden host cells with various metabolic and fitness costs and may lead to other potentially detrimental phenotypic effects. Acquisition of the Pseudomonas syringae megaplasmid pMPPla107 by various Pseudomonads causes sensitivity to a growth-inhibiting substance that is produced in cultures by Pseudomonads during growth under standard laboratory conditions. After approximately 500 generations of laboratory passage of Pseudomonas stutzeri populations containing pMPPla107, strains from two out of six independent passage lines displayed resistance to this inhibitory agent. Resistance was transferable and is, therefore, associated with mutations occurring on pMPPla107. Resequencing experiments demonstrated that resistance is likely due to a large deletion on the megaplasmid in one line, and to a nonsynonymous change in an uncharacterized megaplasmid locus in the other strain. We further used allele exchange experiments to confirm that resistance is due to this single amino acid change in a previously uncharacterized megaplasmid protein, which we name SkaA. These results provide further evidence that costs and phenotypic changes associated with horizontal gene transfer can be compensated through single mutational events and emphasize the power of experimental evolution and resequencing to better understand the genetic basis of evolved phenotypes. This article is part of the theme issue ‘The secret lives of microbial mobile genetic elements’.

scholarly journals Multiple Megaplasmids Confer Extremely High Levels of Metal Tolerance in Alteromonas Strains

2019 ◽  
Vol 86 (3) ◽  
Author(s):  
Kathleen D. Cusick ◽  
Shawn W. Polson ◽  
Gabriel Duran ◽  
Russell T. Hill
Keyword(s):  
Gene Transfer ◽  
Pseudomonas Syringae ◽  
Molecular Mechanisms ◽  
Metal Tolerance ◽  
Bioinformatic Analysis ◽  
Metal Resistance ◽  
Copper Resistance ◽  
The Other ◽  
Copper Tolerance ◽  
Content Type

ABSTRACT Alteromonas is a widely distributed genus of marine Gammaproteobacteria, with representatives shown to be key players in diverse processes, including biogeochemical cycling and biofouling of marine substrata. While Alteromonas spp. are early colonizers of copper-based antifouling paints on marine vessels, their mechanism of tolerance is poorly understood. PacBio whole-genome sequencing of Alteromonas macleodii strains CUKW and KCC02, isolated from Cu/Ni alloy test coupons submerged in oligotrophic coastal waters, indicated the presence of multiple megaplasmids (ca. 200 kb) in both. A pulsed-field gel electrophoresis method was developed and used to confirm the presence of multiple megaplasmids in these two strains; it was then used to screen additional Alteromonas strains for which little to no sequencing data exist. Plasmids were not detected in any of the other strains. Bioinformatic analysis of the CUKW and KCC02 plasmids identified numerous genes associated with metal resistance. Copper resistance orthologs from both the Escherichia coli Cue and Cus and Pseudomonas syringae Cop systems were present, at times as multiple copies. Metal growth assays in the presence of copper, cobalt, manganese, and zinc performed with 10 Alteromonas strains demonstrated the ability of CUKW and KCC02 to grow at metal concentrations inhibitory to all the other strains tested. This study reports multiple megaplasmids in Alteromonas strains. Bioinformatic analysis of the CUKW and KCC02 plasmids indicate that they harbor elements of the Tra system conjugation apparatus, although their type of mobility remains to be experimentally verified. IMPORTANCE Copper is commonly used as an antifouling agent on ship hulls. Alteromonas spp. are early colonizers of copper-based antifouling paint, but their mechanism of tolerance is poorly understood. Sequencing of A. macleodii strains isolated from copper test materials for marine ships indicated the presence of multiple megaplasmids. Plasmids serve as key vectors in horizontal gene transfer and confer traits such as metal resistance, detoxification, ecological interaction, and antibiotic resistance. Bioinformatic analysis identified many metal resistance genes and genes associated with mobility. Understanding the molecular mechanisms and capacity for gene transfer within marine biofilms provides a platform for the development of novel antifouling solutions targeting genes involved in copper tolerance and biofilm formation.

scholarly journals Genetic basis of copper resistance in New Zealand strains of Pseudomonas syringae

2003 ◽  
Vol 56 ◽  
pp. 109-112 ◽  
Author(s):  
J.L. Vanneste ◽  
M.D. Voyle
Keyword(s):  
New Zealand ◽  
Pseudomonas Syringae ◽  
Copper Sulphate ◽  
Minimal Medium ◽  
Genetic Basis ◽  
Copper Resistance

Strains of Pseudomonas syringae able to grow on minimal medium containing 500 mg/litre of copper sulphate were selected from a collection of streptomycinresistant strains isolated in New Zealand From one of these copperresistant strains a 13 kb fragment of DNA was isolated by PCR using primers designed on genes reported to be associated with copper resistance Sequencing of this fragment revealed that a 572 bp and a 275 bp portion had 98 and 95 similarity with ORF A of P syringae pv actinidiae a gene that codes for copper resistance Smaller portions of this 13 kb fragment were highly similar (89 to 100) to portions of another gene involved in copper resistance (copA) from Pseudomonas syringae pv tomato Using this 13 kb fragment as a probe homologous DNA was detected in eight other strains of P syringae which were all subsequently found to be resistant to copper

scholarly journals Experimental Evolution of the Megaplasmid pMPPla107 in Pseudomonas stutzeri Enables Identification of Genes Contributing to Sensitivity to an Inhibitory Agent

2019 ◽  
Author(s):  
Brian A. Smith ◽  
Kevin Dougherty ◽  
Meara Clark ◽  
David A. Baltrus
Keyword(s):  
Pseudomonas Syringae ◽  
Experimental Evolution ◽  
Genetic Basis ◽  
Pseudomonas Stutzeri ◽  
Large Deletion ◽  
Host Cells ◽  
Standard Laboratory ◽  
Fitness Costs ◽  
Killing Activity ◽  
Compensatory Mutations

ABSTRACTHorizontally transferred elements such as plasmids can, at times, burden host cells with various metabolic and fitness costs. Our previous work demonstrated that acquisition of the Pseudomonas syringae megaplasmid pMPPla107 causes sensitivity to a growth inhibiting substance that is produced in cultures during growth under standard laboratory conditions. After 500 generations of laboratory passage of P. stutzeri lines containing pMPPla107, two out of six independent lines displayed resistance to this inhibitory agent. We therefore sequenced the genomes of isolates from each independent evolutionary line to identify the genetic basis of this resistance phenotype through comparative genomics. Our analysis demonstrates that two different compensatory mutations on the megaplasmid ameliorate the sensitivity phenotype: 1) a large deletion of approximately 368kb in pMPPla107 and 2) a SNP in the gene we name skaA for Supernatant Killing Activity. These results provide further evidence that costs associated with horizontal gene transfer can be compensated through single mutational events and emphasize the power of experimental evolution and resequencing to better understand the genetic basis of evolved phenotypes.

scholarly journals Disease Development and Changes in the Natural Pseudomonas syringae pv. tomato Populations on Field Tomato Plants

Plant Disease ◽  
1999 ◽  
Vol 83 (8) ◽  
pp. 759-764 ◽  
Author(s):  
D. A. Cuppels ◽  
J. Elmhirst
Keyword(s):  
Statistical Analysis ◽  
Disease Severity ◽  
Pseudomonas Syringae ◽  
Natural Populations ◽  
Leaf Tissue ◽  
Copper Tolerance ◽  
Disease Development ◽  
Tomato Plants ◽  
Growing Seasons ◽  
Tomato Gene

The probe TPRI, derived from the Pseudomonas syringae pv. tomato gene cluster controlling production of the phytotoxin coronatine, was used in conjunction with the semiselective medium VBTar to trace natural populations of the pathogen on tomato plants from just before planting to harvest. In a survey of transplant seedlings in greenhouses, P. syringae pv. tomato populations ranged from 8 × 100 to 3.2 × 105 CFU/g of leaf tissue. Copper-sprayed seedlings had similar populations to nonsprayed plants, but copper tolerance was common among the P. syringae pv. tomato strains surveyed. Transplant seedlings from three greenhouses were tagged, randomly planted in three grower fields, and monitored for P. syringae pv. tomato and disease severity over two growing seasons. Statistical analysis indicated that, when the P. syringae pv. tomato populations of greenhouse plants were small, as recorded in this study, there was no correlation between greenhouse infestation and disease severity in the field. Environmental conditions played a greater role than greenhouse infestation in disease development. Once formed, leaf lesions remained a good inoculum source (104 to 105 CFU) throughout the 7-week life of the leaf. Bacterial speck damage correlated well in both years (r = 0.80 and r = 0.86, respectively) with P. syringae pv. tomato population levels.

Effects of the pseudomonad phytotoxin coronatine on tomato leaf structure and ultrastructure

1995 ◽  
Vol 53 ◽  
pp. 862-863
Author(s):  
D.A. Palmer ◽  
C.L. Bender
Keyword(s):  
Pseudomonas Syringae ◽  
Membrane Integrity ◽  
Leaf Tissue ◽  
Cell Number ◽  
Cell Ultrastructure ◽  
Response To Treatment ◽  
Prominent Symptom ◽  
Chlorophylls A And B ◽  
Cell Dimensions ◽  
Structure And Ultrastructure

Coronatine is a non-host-specific phytotoxin produced by several members of the Pseudomonas syringae group of pathovars. The toxin acts as a virulence factor in P. syringae pv. tomato, allowing the organism to multiply to a higher population density and develop larger lesions than mutant strains unable to produce the toxin. The most prominent symptom observed in leaf tissue treated with coronatine is an intense spreading chlorosis; this has been attributed to a loss of chlorophylls a and b in tobacco. Coronatine's effects on membrane integrity and cell ultrastructure have not been previously investigated. The present study describes changes in tomato leaves in response to treatment with purified coronatine, infection by a coronatine-producing strain of P. syringae pv. tomato, and infection by a cor" mutant.In contrast to H2O-treated tissue, coronatine-treated tissue showed a diffuse chlorosis extending approximately 5 mm from the inoculation site. Leaf thickness, cell number, and cell dimensions were similar for both healthy and coronatine-treated, chlorotic tissue; however, the epidermal cell walls were consistently thicker in coronatine-treated leaves (Figs, la and lb).

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