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. 1996 Apr;64(4):1407–1412. doi: 10.1128/iai.64.4.1407-1412.1996

Fatty acid composition of the major phospholipids of Pneumocystic carinii: comparison with those in the lungs of normal and methylprednisolone-immunosuppressed rats.

Z Guo 1, D H Beach 1, E S Kaneshiro 1
PMCID: PMC173933  PMID: 8606108

Abstract

Large numbers of viable organisms can be isolated from the corticosteroid-immunosuppressed rat model of Pneumocystis carinii pneumonia. With the development of purification protocols that provide organism preparations of high purity, meaningful lipid biochemical analyses of this important opportunistic pathogen can now be conducted. The phospholipid class composition of the pathogen was reported earlier, together with observations of changes that occur in the rat lungs in response to methylprednisolone immunosuppression treatment. In this report, analyses of the effects of corticosteroids on the fatty acid compositions of the major lung phospholipids, individually isolated and purified by thin-layer chromatography, were elucidated and quantified by gas-liquid chromatography. In response to methylprednisolone, there was a relative increase in palmitate and there were decreases in several unsaturated fatty acids of the rat whole-lung total polar lipids leading to a doubling of the saturation index. Reciprocal changes in the relative concentrations of palmitate and stearate in phosphatidylethanolamine, phosphatidylinositol, lysophosphatidylcholine, and cardiolipin were observed, suggesting that there is tight control of acylation of these phospholipids in the lung. Detailed phospholipid fatty acid analyses were also performed with mixed life cycle stages of P. carinii organisms. The most abundant phospholipids, phosphatidylcholine, phosphatidylethanolamine, and phosphatidylinositol, had much higher concentrations of oleic acid and lower concentrations of palmitate in P. carinii than in lung tissue. Sphingomyelin in lung tissue and P. carinii differed from the glycerophospholipids by the presence of high levels of saturated C(22) and C(24) fatty acids. This study represents the most comprehensive fatty acid analysis of rat lung phospholipids and the changes that occur in response to corticosteroid treatment. It is the first report about the fatty acids of individual phospholipids of the opportunistic protist P. carinii carinii.

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Selected References

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  1. BLIGH E. G., DYER W. J. A rapid method of total lipid extraction and purification. Can J Biochem Physiol. 1959 Aug;37(8):911–917. doi: 10.1139/o59-099. [DOI] [PubMed] [Google Scholar]
  2. Baxter C. F., Rouser G., Simon G. Variations among vertebrates of lung phospholipid case composition. Lipids. 1969 May;4(3):243–244. doi: 10.1007/BF02532640. [DOI] [PubMed] [Google Scholar]
  3. Boylan C. J., Current W. L. Improved rat model of Pneumocystis carinii pneumonia: induced laboratory infections in Pneumocystis-free animals. Infect Immun. 1992 Apr;60(4):1589–1597. doi: 10.1128/iai.60.4.1589-1597.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Ellis J. E., Reilly M. H., Kaneshiro E. S. Identification of an epoxy fatty acid in Pneumocystis carinii lipids. J Eukaryot Microbiol. 1994 Sep-Oct;41(5):87S–87S. [PubMed] [Google Scholar]
  5. FOLCH J., LEES M., SLOANE STANLEY G. H. A simple method for the isolation and purification of total lipides from animal tissues. J Biol Chem. 1957 May;226(1):497–509. [PubMed] [Google Scholar]
  6. Florin-Christensen M., Florin-Christensen J., Kaneshiro E. S. Uptake and metabolism of L-serine by Pneumocystis carinii carinii. J Eukaryot Microbiol. 1995 Nov-Dec;42(6):669–675. doi: 10.1111/j.1550-7408.1995.tb01613.x. [DOI] [PubMed] [Google Scholar]
  7. Furlong S. T., Samia J. A., Rose R. M., Fishman J. A. Phytosterols are present in Pneumocystis carinii. Antimicrob Agents Chemother. 1994 Nov;38(11):2534–2540. doi: 10.1128/aac.38.11.2534. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Guo Z., Kaneshiro E. S. Phospholipid composition of Pneumocystis carinii carinii and effects of methylprednisolone immunosuppression on rat lung lipids. Infect Immun. 1995 Apr;63(4):1286–1290. doi: 10.1128/iai.63.4.1286-1290.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Harwood J. L. Lung surfactant. Prog Lipid Res. 1987;26(3):211–256. doi: 10.1016/0163-7827(87)90004-x. [DOI] [PubMed] [Google Scholar]
  10. Kaneshiro E. S., Cushion M. T., Walzer P. D., Jayasimhulu K. Analyses of Pneumocystis fatty acids. J Protozool. 1989 Jan-Feb;36(1):69S–72S. [PubMed] [Google Scholar]
  11. Kaneshiro E. S., Ellis J. E., Jayasimhulu K., Beach D. H. Evidence for the presence of "metabolic sterols" in Pneumocystis: identification and initial characterization of Pneumocystis carinii sterols. J Eukaryot Microbiol. 1994 Jan-Feb;41(1):78–85. doi: 10.1111/j.1550-7408.1994.tb05938.x. [DOI] [PubMed] [Google Scholar]
  12. Kaneshiro E. S. Positional distribution of fatty acids in the major glycerophospholipids of Paramecium tetraurelia. J Lipid Res. 1980 Jul;21(5):559–570. [PubMed] [Google Scholar]
  13. Kaneshiro E. S., Wyder M. A., Zhou L. H., Ellis J. E., Voelker D. R., Langreth S. G. Characterization of Pneumocystis carinii preparations developed for lipid analysis. J Eukaryot Microbiol. 1993 Nov-Dec;40(6):805–815. doi: 10.1111/j.1550-7408.1993.tb04479.x. [DOI] [PubMed] [Google Scholar]
  14. MacGee J., Williams M. G. Preparation of sphingolipid fatty acid methyl esters for determination by gas-liquid chromatography. J Chromatogr. 1981 Jan 30;205(2):281–288. doi: 10.1016/s0021-9673(00)82656-4. [DOI] [PubMed] [Google Scholar]
  15. Paulsrud J. R., Queener S. F., Bartlett M. S., Smith J. W. Total cellular fatty acid composition of cultured Pneumocystis carinii. J Clin Microbiol. 1993 Jul;31(7):1899–1902. doi: 10.1128/jcm.31.7.1899-1902.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Paulsrud J. R., Queener S. F. Incorporation of fatty acids and amino acids by cultured Pneumocystis carinii. J Eukaryot Microbiol. 1994 Nov-Dec;41(6):633–638. doi: 10.1111/j.1550-7408.1994.tb01525.x. [DOI] [PubMed] [Google Scholar]
  17. Pesanti E. L. Phospholipid profile of Pneumocystis carinii and its interaction with alveolar type II epithelial cells. Infect Immun. 1987 Mar;55(3):736–741. doi: 10.1128/iai.55.3.736-741.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Rice W. R., Singleton F. M., Linke M. J., Walzer P. D. Regulation of surfactant phosphatidylcholine secretion from alveolar type II cells during Pneumocystis carinii pneumonia in the rat. J Clin Invest. 1993 Dec;92(6):2778–2782. doi: 10.1172/JCI116896. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Sheehan P. M., Stokes D. C., Yeh Y. Y., Hughes W. T. Surfactant phospholipids and lavage phospholipase A2 in experimental Pneumocystis carinii pneumonia. Am Rev Respir Dis. 1986 Sep;134(3):526–531. doi: 10.1164/arrd.1986.134.3.526. [DOI] [PubMed] [Google Scholar]
  20. Sleight R. G., Mehta M. A., Kaneshiro E. S. Uptake and metabolism of fluorescent lipid analogs by Pneumocystis carinii. J Eukaryot Microbiol. 1994 Sep-Oct;41(5):111S–111S. [PubMed] [Google Scholar]
  21. Sorice M., Lenti L., Misasi R., Contini C., Cignarella L., Griggi T., Vullo V., Masala C. Evidence for the existence of ganglioside molecules on Pneumocystis carinii from human lungs. Parasitology. 1992 Aug;105(Pt 1):1–6. doi: 10.1017/s0031182000073613. [DOI] [PubMed] [Google Scholar]

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