Hostname: page-component-78c5997874-j824f Total loading time: 0 Render date: 2024-11-16T05:40:28.176Z Has data issue: false hasContentIssue false
  • English
  • Français

Enzymic Proteolysis by Entamoeba histolytica; biochemical characteristics and relationship with invasiveness

Published online by Cambridge University Press:  06 April 2009

R. A. Neal
R. A. Neal
Affiliation:
Wellcome Laboratories of Tropical Medicine, London, N. W. 1
Get access Rights & Permissions [Opens in a new window]

Extract

The proteolytic activity of extracts of Entamoeba histolytica has been further investigated. Casein and gelatin, but not haemaglobin, were hydrolysed. Activity was observed in the pH range 5·8 to 8·5 with optimal activity at pH 7·5 to 7·9. Activity was optimal at 37° C. and sulphydryl groups were not required. Concomitant bacteria showed no proteolytic activity. Hyaluronidase, collagenase and lecithinase could not be detected.

An inhibitor of proteolytic enzyme was present in sera of all animals tested and in egg yolk. All culture media prepared from eggs were inhibitory, but inspissation or dilution of serum inactivated the serum inhibitor. Purified trypsin inhibitors from lima and soy bean were not active against the amoebic enzyme. Proteolytic enzymes were not secreted extracellularly in vitro.

High proteolytic activity was found in two out of five invasive, freshly isolated, strains of E. histolytica and after two series of liver passages of a single strain. The significance of these observations is discussed. It is concluded that the present evidence does not convincingly demonstrate that high proteolytic activity is required for tissue invasion by amoebae, but may accompany another factor.

Type
Research Article
Information
Parasitology , Volume 50 , Issue 3-4 , November 1960 , pp. 531 - 550
Copyright
Copyright © Cambridge University Press 1960

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Balamuth, W. (1946). Improved egg yolk infusion for cultivation of Entamoeba histolytica and other intestinal protozoa. Amer. J. Clin. Path. 16, 380.CrossRefGoogle ScholarPubMed
Bishop, A. (1937). Further observations upon Entamoeba aulastomi Nöller. Parasitology, 29, 57.CrossRefGoogle Scholar
Bradin, J. R. (1953). Studies on the production of hyaluronidase by Endamoeba histolytica. Exp. Parasit. 2, 230.CrossRefGoogle Scholar
Councilman, W. T. & Lafleur, H. A. (1891). Amoebic dysentery. Johns Hopk. Hosp. Rep. 2, 395.Google Scholar
DeLamater, J. N., Michaelson, J. B., Hallman, F. A. & Blumenthal, H. (1954). An investigation into hyaluronidase as a factor in the mechanism of tissue invasion by Endamoeba histolytica. Amer. J. Trop. Med. Hyg. 3, 1.CrossRefGoogle ScholarPubMed
Dobell, C. (1919). The Amoebae Living in Man. London: John Bale, Sons and Danielsson.Google Scholar
Dobell, C. (1928). Researches on the intestinal protozoa of monkeys and man. I. General introduction and II. Description of the whole life history of Entamoeba histolytica in cultures. Parasitology, 20, 357.CrossRefGoogle Scholar
Dobell, C. & Laidlaw, P. P. (1926). On the cultivation of Entamoeba histolytica and some other entozoic amoebae. Parasitology, 18, 283.CrossRefGoogle Scholar
Dobell, C. & Neal, R. A. (1952). Research on the intestinal protozoa of monkeys and man. XII. Bacterial factors influencing the life history of Entamoeba histolytica in cultures. Parasitology, 42, 16.CrossRefGoogle ScholarPubMed
Duspiva, F. (1939). Beiträge zur Histophysiologie des Insektendarmes. I. Untersuchungen über die Verteilung der proteolytischen Enzyme sowie der sekret- und resorptionszellen in Darm von Dytiscus marginalis. Protoplasma, 32, 211.CrossRefGoogle Scholar
Geiman, Q. M. & Ratcliffe, H. L. (1936). Morphology and life-cycle of an amoeba producing amoebiasis in reptiles. Parasitology, 28, 208.CrossRefGoogle Scholar
Hallman, F. A., Michaelson, J. B. & DeLamater, J. N. (1950). The cultivation of Endamoeba histolytica in a defined medium. Amer. J. Trop. Med. 30, 363.CrossRefGoogle Scholar
Harinasuta, C. & Maegraith, B. G. (1958). The demonstration of proteolytic enzyme activity of Entamoeba histolytica by the use of photographic gelatin film. Ann. Trop. Med. Parasit. 52, 508.CrossRefGoogle ScholarPubMed
Holter, H. & Løvtrup, S. (1949). Proteolytic enzymes in Chaos chaos. C.R. Lab. Carlsberg, Sér. chim. 27, 27.Google Scholar
Jones, W. R. (1946). The experimental infection of rats with Entamoeba histolytica; with a method for evaluating the anti-amoebic properties of new compounds. Ann. Trop. Med. Parasit. 40, 130.CrossRefGoogle ScholarPubMed
Kaneko, M. (1956). Investigation on the proteolytic activity of parasitic and free-living amoebae. Kiseichu-gaku Zasshi, 5, 92.Google Scholar
Kohn, J. (1953). A preliminary report of a new gelatin liquefaction method. J. Clin. Path. 6, 249.CrossRefGoogle ScholarPubMed
Laskowski, M. & Laskowski, M. Jr. (1954). Naturally occurring trypsin inhibitors. Advanc. Protein Chem. 9, 203.CrossRefGoogle ScholarPubMed
Mitchell, P. (1958). Membrane penetration and therapeutic value of chemicals. In Strategy of Chemotherapy. Symp. Soc. Gen. Microbiol. 8, 94.Google Scholar
Morrison, W. L. & Neurath, H. (1953). Proteolytic enzymes of the formed elements of human blood. I. Erythrocytes. J. Biol. Chem. 200, 39.CrossRefGoogle ScholarPubMed
Nakamura, M. & Edwards, P. R. Jr (1959 a). Casease in Entamoeba histolytica. Nature, Lond., 183, 397.CrossRefGoogle ScholarPubMed
Nakamura, M. & Edwards, P. R. Jr (1959 b). Enzymes of Entamoeba histolytica. I. Gelatinase. Proc. Soc. Exp. Biol. N.Y., 100, 403.CrossRefGoogle ScholarPubMed
Nakamura, M. & Klein, L. (1957). Absence of collagenase activity in Entamoeba histolytica. J. Parasit. 43, 88.CrossRefGoogle Scholar
Neal, R. A. (1951). Some observations on the variation of virulence and response to chemotherapy of strains of Entamoeba histolytica in rats. Trans. Roy. Soc. Trop. Med. Hyg. 44, 439.CrossRefGoogle ScholarPubMed
Neal, R. A. (1953). Studies on the morphology and biology of Entamoeba moshkovskii Tshalaia, 1941. Parasitology, 43, 253.CrossRefGoogle ScholarPubMed
Neal, R. A. (1956). Proteolytic enzymes in Entamoeba histolytica. Nature, Lond., 178, 599.CrossRefGoogle ScholarPubMed
Neal, R. A. (1958). The pathogenicity of Entamoeba histolytica. Proc. 6th Int. Congr. Trop. Med. Malaria. In the Press.Google Scholar
Neal, R. A. & Vincent, P. (1955). Strain variation in Entamoeba histolytica. I. Correlation of invasiveness in rats with the clinical history and treatment of the experimental infections. Parasitology, 45, 152.CrossRefGoogle ScholarPubMed
Neal, R. A. & Vincent, P. (1956). Strain variation in Entamoeba histolytica. II. The effect of serial liver passage on the virulence. Parasitology, 46, 173.CrossRefGoogle ScholarPubMed
Parker, R. C. (1938). Methods of Tissue Culture, p. 36. London: Hamish Hamilton.Google Scholar
Rees, C. W., Baernstein, H. D., Reardon, L. V. & Phillips, L. (1953). Some interactions in vitro of Endamoeba histolytica and single species of microbial symbionts. Amer. J. Trop. Med. Hyg. 2, 1002.CrossRefGoogle ScholarPubMed
Rothstein, A. (1954). The enzymology of the cell surface. In Protoplasmatologia, 2, (E4) 1. Wien: Springer-Verlag.Google Scholar
Thompson, P. E., McCarthy, D. & Reinertson, J. W. (1954). Observations on the virulence of Endamoeba histolytica during prolonged subcultivation. Amer. J. Hyg. 59, 249.Google ScholarPubMed
Townshend, R. H. (1949). Failure of an attempt to demonstrate hyaluronidase production by Entamoeba histolytica. Trans. Roy. Soc. Trop. Med. Hyg. 42, 314.Google Scholar
Vincent, P. & Neal, R. A. (1960). Duration of invasiveness of Entamoeba histolytica maintained in vitro. Parasitology. 50, 449.CrossRefGoogle ScholarPubMed
Westphal, A. (1938). Die Pathogenese der Amobenruhr bei Mensch und Tier. I. Das Wesen der pathogenetischen Wirksamkeit der Ruhramöbe. Arch. Schiffs-u. Tropenhyg. 42, 343.Google Scholar