Antonie van Leeuwenhoek

, Volume 40, Issue 4, pp 481–527 | Cite as

A study in test reproducibility between laboratories: Report of a Pseudomonas Working Party

Edited for the Working Party
  • P. H. A. Sneath
  • Vera G. Collins
Development and Structure


The results are reported of a collaborative study in laboratories of 17 tests commonly used for pseudomonads, together with statistical analysis of the results in the form of analyses of variance. The studies involved 59 strains.

The following tests showed good or reasonably good consistency between different laboratories: motility if checked by a Craigie tube, growth at 4 C, production of fluorescin, oxidation of glucose and sucrose, gluconate oxidation, hydrolysis of aesculin, arginine and casein, and gelatin hydrolysis by the tube method.

The following were less satisfactory: shape, size and arrangement of organismis, growth at 42 C, oxidase, acid from lactose, reduction of nitrate, acetic acid from ethanol, gelatin hydrolysis by the plate method, and the egg yolk reaction.

The following showed poor consistency or noticeable difficulties in performing or interpreting results of the test: growth at 37 C, the denitrification test of Stanier, Palleroni and Doudoroff, and hydrolysis of urea.

However, with several of the unsatisfactory tests the replicates within a laboratory showed much better reproducibility. This (together with other evidence on the importance of exact control of variables such as temperature, and time of reading, and the occurrence of mutants in some strains) suggests that careful attention to standardization may give much better testing methods. The considerable value of statistical analyses in such work is discussed.


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  1. Ballard, R. W., Palleroni, N. J., Doudoroff, M., Stanier, R. Y. and Mandel, M. 1970. Taxonomy of the aerobic Pseudomonads: Pseudomonas cepacia, P. marginata, P. alliicola and P. caryophylli. — J. Gen. Microbiol. 60: 199–214.Google Scholar
  2. Brough, F. 1950. A rapid microtechnique for the determination of nitrate reduction — J. Bacteriol. 60: 365–366.Google Scholar
  3. Christensen, W. B. 1946. Urea decomposition as a means of differentiating Proteus and paracolon organisms from each other and from Salmonella and Shigella types. — J. Bacteriol. 52: 461–466.Google Scholar
  4. Cohen-Bazire, G., Sistrom, W. R. and Stanier, R. Y. 1957. Kinetic studies of pigment synthesis by non-sulfur purple bacteria. — J. Cell. Comp. Physiol.. 49: 25–68.Google Scholar
  5. Cruickshank, R. (ed.) 1965. Medical Microbiology, p. 235. — E. & S. Livingstone Ltd., Edinburgh.Google Scholar
  6. Davis, G. H. G. and Park, R. W. A. 1962. A taxonomic study of certain bacteria currently classified as Vibrio species. — J. Gen. Microbiol. 27: 101–119.Google Scholar
  7. Frazier, W. C. 1926. A method for the detection of changes in gelation due to bacteria. — J. Infect. Dis. 39: 302–309.Google Scholar
  8. Friedman, M. 1937. The use of ranks to avoid the assumption of normality implicit in the analysis of variance. — J. Amer. Statist. Ass. 32: 675–701.Google Scholar
  9. Haynes, W. C. 1951. Pseudomonas aeruginosa-its characterization and identification. — J. Gen. Microbiol. 5: 939–950.Google Scholar
  10. Hugh, R. and Leifson, E. 1953. The taxonomic significance of fermentative versus oxidative metabolism of carbohydrates by various Gram-negative bacteria. — J. Bacteriol. 66: 24–26.Google Scholar
  11. Jessen, O. 1965. Pseudomonas aeruginosa and other green fluorescent pseudomonads. A taxonomic study. — Munksgaard, Copenhagen.Google Scholar
  12. King, E. O., Ward, M. K. and Raney, D. E. 1954. Two simple media for the demonstration of pyocyanin and fluorescin. — J. Lab. Clin. Med. 44: 301–305.Google Scholar
  13. Klinge, K. 1960. Differential techniques and methods of isolation of Pseudomonas. — J. Appl. Bacteriol 23: 442–462.Google Scholar
  14. Kovacs, N. 1956. Identification of Pseudomonas pyocyanea by the oxidase reaction. — Nature (London) 178: 703.Google Scholar
  15. Lapage, S. P., Bascomb, B., Willcox, W. R. and Curtis, M. A. 1970. Computer identification of bacteria. In A.Baillie and R. J.Gilbert, (eds.) Automation, mechanization and data handling in microbiology, pp. 1–22. — Academic Press, London and New York.Google Scholar
  16. Lysenko, O. 1961. Pseudomonas-an attempt at a general classification. — J. Gen. Microbiol. 25: 379–408.Google Scholar
  17. Manual of Microbiological Methods. 1957. Ed. by Committee on Bacteriological Technic of American Society for Microbiology. — McGraw-Hill, New York.Google Scholar
  18. Moroney, M. J. 1956. Facts from Figures, 3rd ed. — Penguin Books, Harmondsworth, Middlesex.Google Scholar
  19. Rhodes, M. E. 1961. The characterization of Pseudomonas fluorescens with the aid of an electronic computer. — J. Gen. Microbiol. 25: 331–345.Google Scholar
  20. Shimwell, J. L., Carr, J. G. and Rhodes, M. 1960. Differentiation of Acetomonas and Pseudomonas. — J. Gen. Microbiol. 23: 283–286.Google Scholar
  21. Smith, N. R., Gordon, R. E. and Clark, F. E. 1952. Aerobic spore-forming bacteria. — U.S. Dept. of Agriculture. Agriculture Monograph No. 16, Washington, D.C.Google Scholar
  22. Sneath, P.H.A. 1956. Cultural and biochemical characteristics of the genus Chromobacterium. —J. Gen Microbiol. 15: 70–98.Google Scholar
  23. Sneath, P.H.A. 1966. Identification methods applied to Chromobacterium, p. 15–20, In B. M.Gibbs and F. A.Skinner (eds.), Identification methods for microbiology, Part A. — Academic Press, London and New York.Google Scholar
  24. Sneath, P. H. A. 1971. Theoretical aspects of microbiological taxonomy, p. 581–586. In A.Pérez-Miravete and D.Peláez (eds.), Recent Advances in Microbiology, X International Congress for Microbiology. — Association Mexicana de Microbiologia, Mexico, D.F.Google Scholar
  25. Sneath, P. H. A. and Johnson, R. 1972. The influence on numerical taxonomic similarities of errors in microbiological tests. — J. Gen. Microbiol. 72: 377–392.Google Scholar
  26. Snedecor, G. W. 1956. Statistical methods applied to experiments in agriculture and biology, 5th ed. — Iowa State University Press, Ames, Iowa.Google Scholar
  27. Sokal, R. R. and Rohlf, F. J. 1969. Biometry, the principles and practice of statistics in biological research. — W. H. Freeman, San Francisco.Google Scholar
  28. Stanier, R. Y., Palleroni, N. J. and Doudoroff, M. 1966. The aerobic pseudomonads: a taxonomic study. — J. Gen. Microbiol. 43: 159–271.Google Scholar
  29. Stewart, D. J. 1965. The urease activity of fluorescent pseudomonads. — J. Gen. Microbiol. 41: 169–174.Google Scholar
  30. Thornley, M. J. 1960. The differentiation of Pseudomonas from other gram negative bacteria on the basis of arginine metabolism. — J. Bacteriol. 23: 37–52.Google Scholar

Copyright information

© H. Veenman & Zonen B. V. 1974

Authors and Affiliations

  • P. H. A. Sneath
    • 1
  • Vera G. Collins
    • 1
  1. 1.MRC Microbial Systematics UnitThe UniversityLeicesterEngland

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