Cardiolipin (1) is a dimeric phospholipid found in the mitochondrial membranes of both plants and animals. In order to understand better its role, we report the preparation of an immobilised analogue (2) using phosphoramidite chemistry; the probe has been used successfully to bind a recombinant protein containing a cardiolipin-binding domain.
View Article and Find Full Text PDFPatients with chronic fatigue syndrome (CFS) are affected by symptoms of cognitive dysfunction and neurological impairment, the cause of which has yet to be elucidated. However, these symptoms are strikingly similar to those of patients presented with D-lactic acidosis. A significant increase of Gram positive facultative anaerobic faecal microorganisms in 108 CFS patients as compared to 177 control subjects (p<0.
View Article and Find Full Text PDFThe dual specificity phosphatase PTEN exerts its tumour suppressor and cell-migration regulatory functions by dephosphorylating the phospholipid substrate, phosphatidylinositol-3,4,5-trisphosphate (PI(3,4,5)P(3)), and phosphotyrosine protein substrates. PTEN functions are regulated by phospholipid binding, interactions with other cellular proteins and phosphorylation at multiple sites. Precisely, how the phosphorylation and binding events modulate PTEN activity and structure remains mostly unclear.
View Article and Find Full Text PDFAutophosphorylation is a key event in the activation of protein kinases. In this study, we demonstrate that autophosphorylation of the recombinant Src family kinase Hck leads to a 20-fold increase in its specific enzymatic activity. Hck was found to autophosphorylate readily to a stoichiometry of 1.
View Article and Find Full Text PDFInsulin treatment of Drosophila melanogaster Kc 167 cells induces the multiple phosphorylation of a Drosophila ribosomal protein, as judged by its decreased electrophoretic mobility on two-dimensional polyacrylamide gels. The extent to which insulin induces this response is potentiated by cycloheximide and blocked by pretreatment with rapamycin. Isolation and mass spectrometric analysis revealed that the multiply phosphorylated protein was the larger of two Drosophila melanogaster orthologues of mammalian 40S ribosomal protein S6, termed here DS6A.
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