Efficient mechanical cell disruption of Escherichia coli by an ultrasonicator and recovery of intracellular hepatitis B core antigen

Chin Woi Ho, Tsuey Kee Chew, Tau Chuan Ling, Suryani Kamaruddin, Wen Siang Tan, Beng Ti Tey

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58 Citations (Scopus)


Hepatitis B core antigen (HBcAg) expressed intracellularly in Escherichia coli, hence cell disruption process is the prerequisite step to recover this protein. The objective of this study was to develop an efficient mechanical cell disruption method (ultrasonication) for the release of HBcAg. The released intracellular protein was subsequently purified by the combination of centrifugation, precipitation, dialysis and sucrose gradient ultracentrifugation. The results show that the cell disruption and HBcAg release rates increased with the increase of acoustic power. Besides, the optimal cell suspension volume (15 ml) and sonication time (90 min) for the disruption of E. coli cells and the release of intracellular HBcAg were determined. Ultrasonication was found to be more effective than enzymatic method with respect to the release of HBcAg. HBcAg recovered from the cell lysate, resulted from ultrasonication, is 22 times higher than that of the enzymatic method. Electron microscopic analysis showed that the purified HBcAg assembled into particles that closely resemble the viral nucleocapsid form. These particles reacted with anti-HBcAg monoclonal antibody in enzyme-linked immunosorbent assay (ELISA) showing that it is functionally active.

Original languageEnglish
Pages (from-to)1829-1834
Number of pages6
JournalProcess Biochemistry
Issue number8
Publication statusPublished - Aug 2006
Externally publishedYes


  • Cell disruption
  • Escherichia coli
  • HBcAg
  • Lysozyme
  • Ultrasonication

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