Raoultella planticola explained

Raoultella planticola is a Gram-negative[1] bacterium of the genus Raoultella.[2] [3] [4] [5] [6] [7] R. planticola is quite similar in appearance to Klebsiella pneumoniae and must be identified based on growth habits or DNA analysis. A number of strains have been identified.[8] [9]

Human infection

Infections are rare, and mostly seen in immunocompromised patients.[10] [11] [12] R. planticola has been determined to have complicated at least one case of severe pancreatitis.[13]

Strains

A strain of Raoultella planticola, Cd-1 has been found which grows anaerobically at high aqueous cadmium concentrations and precipitates insoluble cadmium sulfide. This strain has been isolated from reducing salt marsh sediments and may be useful in bioremediation of cadmium from exposed soils.[14]

Taxonomic reclassification

Raoultella planticola was formerly classified as part of the genus Klebsiella. It was reclassified along with several other Klebsiella species in 2001.[15]

Genetic modification

In the late 1980s R. planticola was genetically modified by inserting a plasmid from Zymomonas mobilis. This plasmid codes for the enzyme pyruvate decarboxylase which, along with alcohol dehydrogenase already present in the bacteria allow it to produce ethanol. The bacteria already does produce ethanol when metabolizing hexoses and pentoses, but very inefficiently. R. planticola was chosen to receive this gene as it already had metabolic pathways to breakdown pentose sugars such as xylose, which is a main component of agricultural and forest residues.[16] [17] The results showed that the genetically modified strain could produce ethanol but were killed at concentrations of ethanol greater than 5%. The modified strain also produced more ethanol at lower pH (5.4) and ethanol production decreased as pH increased.

In the early 1990s, a biotech company set out to solve a problem: how to destroy crop residue safely. Some crops' residues harbor plant pathogens. Burning is occasionally used to destroy the residue and pathogens, but this is a fire hazard and can be dangerous for the environment. This company realized that, because R. planticola is an aggressive and abundant soil bacterium, it could be genetically modified to destroy crop residue and also create ethanol.

Testing of this process was originally limited to sterile soil. Ph.D. research conducted at Oregon State University, supervised by Elaine Ingham, obtained a sample of the genetically modified organism for assessing ecological effects through the German Institut für Biotechnologie and, testing it in non-sterile (ordinary) soil, found that the modified bacteria caused small amounts of alcohol in the soil.[18] [19] [20] While this level is several hundred times lower than required to affect planth growth, this fact combined with the fact that R. planticola is already found growing in the root systems of all kinds of plants everywhere, sparked a doomsday myth.[21] [19]

Fallacy of GMO claims

Dr Ingham claimed to a New Zealand Commission that "the likely effect of allowing the field trial [with the [[genetically modified bacterium|genetically modified bacteria]] in question] would have been to destroy terrestrial plants".[21] [19] [22] Ingham's suggestion of a possibility of "worldwide plant death" attracted attention from the scientific community. However, they were unable to find any evidence that these claims had been submitted to scientific publication in a peer-reviewed journal, and no evidence was found to indicate the U.S. EPA or U.S. Dept. of Agriculture had reviewed or approved any trials for SDF20.[22] [23] Additionally, the SDF20 was found to have produced 20 micrograms per milliliter of alcohol in the soil which is several hundred times lower than that required to affect plant growth.[24] [23]

Elaine Ingham has issued a public apology for submitting false claims about ecological impact of GMOs.[25]

The Green Party of New Zealand has issued a public apology for misleading statements and acknowledging that a cited research was never published.[26]

In the episode "The Pyramid at the End of the World" of the BBC television show Doctor Who, the Doctor stops a genetically modified strain of R. planticola from causing a worldwide plant and animal die-off similar to the scenario that some scientists have speculated about.

Further reading

External links

Notes and References

  1. Bagley. Susan T.. Seidler. Ramon J.. Brenner. Don J.. Klebsiella planticola sp. nov.: A new species of enterobacteriaceae found primarily in nonclinical environments. Current Microbiology. March 1981. 6. 2. 105–109. 10.1007/BF01569013. 19935030.
  2. http://zipcodezoo.com/Bacteria/R/Raoultella_planticola/ Raoultella planticola
  3. http://data.gbif.org/species/13469050 Data Use Agreement - GBIF Portal
  4. http://data.gbif.org/species/browse/taxon/13469050 Data Use Agreement - GBIF Portal
  5. http://www.ubio.org/browser/details.php?namebankID=2558203 Namebank Record Detail
  6. http://www.nlbif.nl/species_details.php?name=Raoultella+planticola NLBIF : Raoultella planticola (Bagley et al. 1982) Drancourt et al. 2001
  7. http://www.eol.org/pages/972639 Raoultella planticola - Encyclopedia of Life
  8. https://www.uniprot.org/taxonomy/575 Raoultella planticola (Klebsiella planticola)
  9. http://www.straininfo.net/taxa/3521 Raoultella planticola Taxon Passport
  10. 10.1016/j.rmcr.2017.03.018 . 28409111 . 2017 . Westerveld . D. . Hussain . J. . Aljaafareh . A. . Ataya . A. . A Rare Case of Raoultella planticola Pneumonia: An Emerging Pathogen . Respiratory Medicine Case Reports . 21 . 69–70 . 5382143 .
  11. Huynh . Jessica . Fleet . Jamie . Peng . Jonathan . La . Julie . Wyne . Ahraaz . 2018-09-06 . A clinical vignette on Raoultella planticola bacteremia . Official Journal of the Association of Medical Microbiology and Infectious Disease Canada . en . 3 . 3 . 137–140 . 10.3138/jammi.2017-0005 . 2371-0888.
  12. Povlow . Michael R . Carrizosa . Jaime . Jones . Adriana . 2017-07-24 . Raoultella Planticola: Bacteremia and Sepsis in a Patient with Cirrhosis . Cureus . 9 . 7 . e1508 . 10.7759/cureus.1508 . free . 28948128 . 5608487 . 2168-8184.
  13. Alves MS, Riley LW, Moreira BM . A case of severe pancreatitis complicated by Raoultella planticola infection . J. Med. Microbiol. . 56 . Pt 5 . 696–8 . May 2007 . 17446297 . 10.1099/jmm.0.46889-0. free .
  14. Sharma. P. K.. Balkwill. D. L.. Frenkel. A.. Vairavamurthy. M. A.. A New Klebsiella planticola Strain (Cd-1) Grows Anaerobically at High Cadmium Concentrations and Precipitates Cadmium Sulfide. Applied and Environmental Microbiology. 1 July 2000. 66. 7. 3083–3087. 10.1128/AEM.66.7.3083-3087.2000. 10877810. 92115. 2000ApEnM..66.3083S.
  15. 11411716. 2001. Drancourt. M. Bollet. C. Carta. A. Rousselier. P. Phylogenetic analyses of Klebsiella species delineate Klebsiella And raoultella gen. nov., with description of Raoultella ornithinolytica comb. Nov., Raoultella terrigena comb. Nov. And Raoultella planticola comb. Nov. 51. Pt 3. 925–32. International Journal of Systematic and Evolutionary Microbiology. 10.1099/00207713-51-3-925.
  16. Tolan. JS. Finn. RK. Fermentation of d-Xylose to Ethanol by Genetically Modified Klebsiella planticola.. Applied and Environmental Microbiology. September 1987. 53. 9. 2039–44. 10.1128/AEM.53.9.2039-2044.1987. 16347427. 204054. 1987ApEnM..53.2039T.
  17. Feldmann. Sigrun. Sprenger. Georg A.. Sahm. Hermann. Ethanol production from xylose with a pyruvate-formate-lyase mutant of Klebsiella planticola carrying a pyruvate-decarboxylase gene from Zymomonas mobilis. Applied Microbiology and Biotechnology. August 1989. 31. 2. 152–157. 10.1007/BF00262454. 29865373.
  18. Ph.D. . Michael T . Holmes . Ecological assessment after the addition of genetically engineered Klebsiella planticola SDF20 into soil . Oregon State University . 1995. 1957/34510 .
  19. Good Intentions and Engineering Organisms that Kill Wheat . Elaine Ingham . Elaine Ingham . . 18 . Winter 1999 . 2015-11-24.
  20. Effects of Klebsiella planticola SDF20 on soil biota and wheat growth in sandy soil . Applied Soil Ecology . 1999-01-03 . Holmes . M. T. . Ingham . E. R. . Elaine Ingham . Doyle . J. D. . Hendricks . C. W. . 11 . 1 . 67–78 . 10.1016/S0929-1393(98)00129-2 . 1999AppSE..11...67H .
  21. Web site: Klebsiella planticola—The Gene-Altered Monster That Almost Got Away. San Francisco State University. 2015-11-24.
  22. New Zealand GMO debacle undermines green lobby . 2001 . 10.1038/86618 . Fletcher . Liz . Nature Biotechnology . 19 . 4 . 292 . 11283556 . 33027459 . free .
  23. Web site: Evidence in Rebuttal - Life Sciences Network . February 5, 2021.
  24. Web site: Porterfield. Andrew. Did you hear about the GMO that almost destroyed all life?. geneticliteracyproject.org. Genetic Literacy Project. 6 September 2016. 2016-09-06.
  25. Fletcher. Liz. New Zealand GMO debacle undermines green lobby. Nature Biotechnology. 19. 4. 292. Nature. 10.1038/86618. 11283556. 2001. 33027459. free.
  26. Web site: Aotearoa. Green Party of. Amendment to evidence presented to the Royal Commission of Inquiry into Genetic Modification. gene.ch. 6 October 2016.

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Raoultella planticola".

Except where otherwise indicated, Everything.Explained.Today is © Copyright 2009-2024, A B Cryer, All Rights Reserved. Cookie policy.