Organophosphate (OP) agents are continuously utilized in large amount throughout the globe for crop protection and public health, thereby creating a potential concern on human health. OP agent as an anticholinesterase also acts on the endocannabinoid (EC)-hydrolases, i.e., fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL), to reveal unexpected adverse effects including ADHD-like behaviors in adolescent male rats. The present investigation examines a hypothesis that OP compound inhibiting the EC-hydrolase(s) dysregulates the EC-signaling system, triggering apoptosis in neuronal cells. Ethyl octylphosphonofluoridate (EOPF), as an OP probe, preferably acts on FAAH over MAGL in intact NG108-15 cells. Anandamide (AEA), an endogenous FAAH substrate, is cytotoxic in a concentration-dependent manner, although 2-arachidonoylglycerol, an endogenous MAGL substrate, gives no effect in the concentrations examined here. EOPF pretreatment markedly enhances AEA-induced cytotoxicity. Interestingly, the cannabinoid receptor blocker AM251 diminishes AEA-induced cell death, whereas AM251 does not prevent the cell death in the presence of EOPF. The consistent results are displayed in apoptosis markers evaluation (caspases and mitochondrial membrane potential). Accordingly, FAAH inhibition by EOPF suppresses AEA-metabolism, and accumulated excess AEA overstimulates both the cannabinoid receptor- and mitochondria-mediated apoptotic pathways.
        
Title: Genome sequence of Xanthomonas oryzae pv. oryzae suggests contribution of large numbers of effector genes and insertion sequences to its race diversity Inoue Y, Takeya M, Sasaki A, Kaki H Ref: , 39:275, 2005 : PubMed
The plant-pathogenic prokaryote Xanthomonas oryzae pv. oryzae (Xoo) causes bacterial blight, one of the most important diseases of rice. The bacterium is a model organism for the analysis of plant-pathogen interaction, because more than 30 races differing in virulence and 25 resistance genes in rice have been reported to date. We present here the complete genome sequence of Xoo strain MAFF 311018. The size of the genome was 4,940,217 bp, in a single circular chromosome. The genome structure of Xoo MAFF 311018 was characterized by large numbers of effector (avr) genes of the avrBs3/pth family and insertion sequences (ISs). RFLP analysis of diverse strains using ISXo1 as a probe suggests that the prevalence of mobile elements in this species, which can bring about genome inversions and rearrangement, may have played a major role in generating the high degree of genetic diversity and race differentiation characteristic of this pathogen. The Xoo MAFF 311018 sequence was also highly similar to those of X. axonopodis pv. citri and X. campestris pv. campestris with the exception of the large number of effectors and IS elements, and numerous inversions and rearrangements.
The first chordates appear in the fossil record at the time of the Cambrian explosion, nearly 550 million years ago. The modern ascidian tadpole represents a plausible approximation to these ancestral chordates. To illuminate the origins of chordate and vertebrates, we generated a draft of the protein-coding portion of the genome of the most studied ascidian, Ciona intestinalis. The Ciona genome contains approximately 16,000 protein-coding genes, similar to the number in other invertebrates, but only half that found in vertebrates. Vertebrate gene families are typically found in simplified form in Ciona, suggesting that ascidians contain the basic ancestral complement of genes involved in cell signaling and development. The ascidian genome has also acquired a number of lineage-specific innovations, including a group of genes engaged in cellulose metabolism that are related to those in bacteria and fungi.
A unique feature of lipoprotein lipase (LpL), the rate-limiting enzyme in the hydrolysis of circulating triglycerides, is its movement from its cell of synthesis, adipocyte or myocyte, to its site of action, the luminal endothelial surface. This involves processes that allow LpL to be released from the adipocyte cell surface and transferred against the flow of interstitial fluid to the luminal surface of endothelial cells. LpL, an unstable enzyme, must retain its activity during this process. Whether a chaperone-like molecule is involved in LpL stabilization and transport is unclear. In the present study, we tested the hypothesis that endothelial cells secrete factors that release LpL and promote its transfer to the luminal endothelial surface. Incubation of adipocytes with endothelial cell conditioned medium (ECCM) led to release of about 2-fold more LpL activity than control medium. Medium from endothelial cells exposed to lysophosphatidylcholine (lyso-ECCM), a product of LpL lipolysis of lipoproteins, released approximately 3-fold more LpL than ECCM. Concomitant with the release of LpL, adipocyte cell surface heparan sulfate (HS) proteoglycans were degraded suggesting that lyso-ECCM contained a heparanase-like activity. More heparanase was found in media from the basolateral than the apical side of lysolecithin-stimulated polarized endothelial cells. In coculture experiments, lipolysis and lysolecithin stimulation of endothelial cells increased LpL release from adipocytes. LpL released by lyso-ECCM remained stable and did not lose enzymatic activity at 37 degrees C for 1 h. LpL activity was also stabilized by heparanase-digested fragments of HS (HS oligosaccharide) and by purified LpL binding decasaccharide. Moreover, LpL.HS oligosaccharide complexes crossed endothelial cell monolayers and bound to the apical side of the cells. Thus, an endothelial heparanase may play a critical role in releasing subendothelial HS bound proteins, and specific HS oligosaccharides produced by this enzyme may serve as extracellular chaperones.
        
Title: Biotinylation of lipoprotein lipase and hepatic triglyceride lipase: application in the assessment of cell binding sites Sivaram P, Wadhwani S, Klein MG, Sasaki A, Goldberg IJ Ref: Analytical Biochemistry, 214:511, 1993 : PubMed
Lipoprotein lipase (LPL) and hepatic triglyceride lipase (HL) were biotinylated using N-hydroxysuccinamide ester of biotin (25-fold molar excess) which was incorporated into the lysine amino groups of the enzyme protein. By assessing enzyme activity and heparin-agarose affinity a biotinylation protocol which did not denature lipases was developed. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis showed that biotinylated LPL (bLPL) has the same mobility as that of unlabeled or iodinated LPL. Receptor binding activity of bLPL was studied in (i) cell binding experiments using cultured bovine aortic endothelial cells and (ii) ligand blotting experiments using endothelial cell plasma membranes. Endothelial cells in culture bound similar amounts of bLPL and 125I-LPL. We previously described a 116-kDa heparin-releasable LPL binding protein (hrp-116) on endothelial cells. Using biotinylated lipases in ligand blotting experiments we now demonstrate that both bLPL and biotinylated HL can bind to hrp-116. bLPL in addition also bound to low-density lipoprotein receptor related protein in ligand blotting. Thus, our protocol has produced biotinylated lipases which are both chemically and biologically active and can be used instead of iodinated lipases.
Following the discovery of a new series of 1-benzyl-4-[2-(N-benzoyl-N-methylamino)ethyl]piperidine (2) derivatives with a potent anti-acetylcholinesterase (anti-AChE) activity, we extended the structure-activity relationships (SAR) to rigid analogues (4) and 1-benzyl-4-[2-(N-benzoyl-N-phenylamino)ethyl]piperidine derivatives (3). Introduction of a phenyl group on the nitrogen atom of the amide moieties resulted in enhanced activity. The rigid analogue containing isoindolone (9) was found to exhibit potent anti-AChE activity comparable to that of 2. Furthermore, replacement of the isoindolone with other heterobicyclic ring systems was examined. Among the compounds prepared in these series, 1-benzyl-4-[2-[4-(benzoylamino)phthalimido]ethyl]piperidine hydrochloride (19) (IC50 = 1.2 nM) is one of the most potent inhibitors of AChE. Compound 19 showed a definite selectivity to AChE over the BCHE (about 34700-fold) and, at dosages of 10-50 mg/kg, exerted a dose-dependent inhibitory effect on AChE in rat brain.
A series of 1-benzyl-4-[2-(N-benzoylamino)ethyl]piperidine derivatives was synthesized and evaluated for anti-acetylcholinesterase (anti-AChE) activity. Substituting the benzamide with a bulky moiety in the para position led to a substantial increase in activity. Introduction of an akyl or phenyl group at the nitrogen atom of benzamide dramatically enhanced the activity. The basic quality of the nitrogen atom of piperidine appears to play an important role in the increased activity, since the N-benzoylpiperidine derivative was almost inactive. We found that 1-benzyl-4-[2-(N-[4'-(benzylsulfonyl) benzoyl]-N-methylamino]ethyl]piperidine hydrochloride (21) (IC50 = 0.56 nM) is one of the most potent inhibitors of acetylcholinesterase. Compound 21 showed an affinity 18,000 times greater for AChE than for BuChE. At a dose of 3 mg/kg, 21 produced a marked and significant increase in acetylcholine (ACh) content in the cerebral vortex and hippocampus of rats. Compound 21 was chosen for advanced development as an antidementia agent.