Colourimetric Determination of Phospholipase Activities in Balamuthia mandrillaris
Syed Razi Haider
DOI : 10.3844/ajbbsp.2007.171.179
American Journal of Biochemistry and Biotechnology
Volume 3, Issue 3
Balamuthia mandrillaris is a recently identified protozoan pathogen that can cause fatal granulomatous encephalitis however the pathogenesis and pathophysiology associated with Balamuthia encephalitis remain unclear. We have recently isolated B. mandrillaris from a 33-years old male who died of encephalitis. Using this isolate, we demonstrated for the first time that B. mandrillaris exhibited phospholipase activities. More specifically, B. mandrillaris exhibited phospholipase A2 and phospholipase D activities. For the first time we used colourimetric technique based on spectrophotometer and designed phospholipases assays to determine these phospholipase activities. The functional role of phospholipases was determined in in vitro assays using human brain microvascular endothelial cells (HBMEC). We observed that PLA2-specific inhibitor i.e., cytidine 5'-diphosphocholine significantly inhibited B. mandrillaris binding to HBMEC. Similarly PLD inhibitor i.e., compound 48/80 inhibited B. mandrillaris binding to HBMEC. Moreover, both inhibitors inhibited B. mandrillaris-mediated HBMEC cytotoxicity. Overall these results clearly demonstrate that phospholipases are important virulence determinants in B. mandrillaris. Further studies will identify the precise role of phospholipases in the pathogenesis of B. mandrillaris, which may help develop therapeutic interventions. Using a novel spectrophotometric-based assay we demonstrated for the first time that B. mandrillaris exhibit phospholipase activities.
© 2007 Syed Razi Haider. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.