20650684

not annotated - annotated - LINNAEUS only

Possible roles of phospholipase A(2) in the biological activities of Acanthamoeba castellanii (T4 Genotype).

Using phospholipases A(2)-specific spectrophotometric assays, it was shown that A. castellanii lysates and their conditioned medium exhibit phospholipase activities. The extracellular levels of PLA(2)detected were significantly reduced compared with the cell-associated enzyme (P<0.05). Sphinganine, a PLA(2)inhibitor showed robust amoebistatic properties but had no effect on the viability of A. castellanii. The potency of sphinganine was demonstrated effectively towards purified PLA(2)derived from porcine pancreas. Using sphinganine, it was observed that PLA(2)is involved in neither binding nor cytotoxicity of the human brain microvascular endothelial cells due to A. castellanii. Unlike as was the case for Dictyostelium amoebae, PLA(2) appeared to be involved in A. castellanii phagocytosis of the fluorescently-labelled polystyrene beads. Horseradish peroxidase was used as a tracer molecule to develop assays to study pinocytosis in A. castellanii. The findings revealed that sphinganine impedes phagocytosis but augments pinocytosis in A. castellanii suggesting distinct nature of processes. A complete understanding of the role of phospholipases in the biology and pathogenesis of A. castellanii infections will determine their potential as therapeutic targets.



Ann file

T1	Species 69 93	Acanthamoeba castellanii

N1 Reference T1 Taxonomy:5755

T2 Species 191 205 A. castellanii

N2 Reference T2 Taxonomy:5755

T3 Species 508 522 A. castellanii

N3 Reference T3 Taxonomy:5755

T4 Species 735 740 human

N4 Reference T4 Taxonomy:9606

T5 Species 786 800 A. castellanii

N5 Reference T5 Taxonomy:5755

T6 Species 886 900 A. castellanii

N6 Reference T6 Taxonomy:5755

T7 Species 963 974 Horseradish

N7 Reference T7 Taxonomy:3704

T8 Species 1058 1072 A. castellanii

N8 Reference T8 Taxonomy:5755

T9 Species 1162 1176 A. castellanii

N9 Reference T9 Taxonomy:5755

T10 Species 1308 1322 A. castellanii

N10 Reference T10 Taxonomy:5755