Parasitology Research

, Volume 112, Issue 3, pp 1221–1227 | Cite as

Silencing of xylose isomerase and cellulose synthase by siRNA inhibits encystation in Acanthamoeba castellanii

  • Yousuf Aqeel
  • Ruqaiyyah Siddiqui
  • Naveed Ahmed KhanEmail author
Original Paper


A key challenge in the successful treatment of Acanthamoeba infections is its ability to transform into a dormant cyst form that is resistant to physiological conditions and pharmacological therapies, resulting in recurrent infections. The carbohydrate linkage analysis of cyst walls of Acanthamoeba castellanii showed variously linked sugar residues, including xylofuranose/xylopyranose, glucopyranose, mannopyranose, and galactopyranose. Here, it is shown that exogenous xylose significantly reduced A. castellanii differentiation in encystation assays (P < 0.05 using paired t test, one-tailed distribution). Using small interfering RNA (siRNA) probes against xylose isomerase and cellulose synthase, as well as specific inhibitors, the findings revealed that xylose isomerase and cellulose synthase activities are crucial in the differentiation of A. castellanii. Inhibition of both enzymes using siRNA against xylose isomerase and cellulose synthase but not scrambled siRNA attenuated A. castellanii metamorphosis, as demonstrated by the arrest of encystation of A. castellanii. Neither inhibitor nor siRNA probes had any effect on the viability and extracellular proteolytic activities of A. castellanii.


Xylose Cyst Wall Basic Local Alignment Search Tool Xylose Isomerase Acanthamoeba Castellanii 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This work was partially supported by grants from the Aga Khan University.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Yousuf Aqeel
    • 1
  • Ruqaiyyah Siddiqui
    • 1
  • Naveed Ahmed Khan
    • 1
    Email author
  1. 1.Department of Biological and Biomedical SciencesAga Khan UniversityKarachiPakistan

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