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Abstract: Compositions of neutral and sulfated glucuronyl glycosphingolipids purified from human motor and sensory nerves and myelins were studied. Higher neutral glycosphingolipids (fraction B), which were separated from GazlCer (fraction A), were analyzed by TLC and TLC-immunostaining. Both nerve myelins contained paragloboside (nLc4Cer) and nLc6Cer dominantly as major higher glycosphingolipids and very little globoside (Gb4Cer), whereas both nerves contained Gb4Cer and nLc4Cer. Besides these major glycosphingolipids, a neutral glycolipid containing asialoGMI (Gg4Cer) epitope and other minor components such as ceramide trihexoside and ceramide dihexoside were detected in both nerves and their myelins. Furthermore, sulfated glucuronyl nLc4Cer and n Lc6Cer, which were monoclonal antibody HNK-1 reactive glycolipids, were detected in both nerves and myelins.  相似文献   
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The process of digestion of captured feeds in a pitcher, an insect-trapping organ, ofNepenthes was studied. Changes in bacterial population, pH and NH4 + concentrations in pitcher juice were examined. Strong activities of both acid- and alkaline phosphatase, phosphoamidase, esterase C4 and esterase C8 were found in the pitcher juice. Optimum pH of proteases in the juice and those secreted from bacteria showed pH 3.0 and pH 8.0–9.0, respectively. Twenty six strains of bacteria were isolated from 4 pitchers: 10 strains were gram positive, 16 strains were gram negative (10 strains had casein hydrolase activity). A proton excretion was induced by NH4 + released from the added solutions, and accordingly, the pH of the solutions fell. As a simulation model of the digestion process of feeds in pitcher juice and polypeptone solution was added into the washed pitcher. A good correlation was found among the NH4 + concentration, pH and bacterial cell titer.  相似文献   
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Excretory and secretory (ES) products collected from adult worms of Strongyloides ratti stimulated interleukin-3 (IL-3) production with mesenteric lymph node cells from infected C57BL/6 mice, but not with normal mesenteric lymph node cells. The IL-3 stimulating components were not major IgG binding antigens. Activity of the IL-3 stimulating components was stable by treatment with protease, although reduced by heating in boiling water.  相似文献   
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Rhodococcus (opacus) erythropolis HL PM-1 grows on 2,4,6-trinitrophenol or 2,4-dinitrophenol (2,4-DNP) as a sole nitrogen source. The NADPH-dependent F420 reductase (NDFR; encoded by npdG) and the hydride transferase II (HTII; encoded by npdI) of the strain were previously shown to convert both nitrophenols to their respective hydride Meisenheimer complexes. In the present study, npdG and npdI were amplified from six 2,4-DNP degrading Rhodococcus spp. The genes showed sequence similarities of 86 to 99% to the respective npd genes of strain HL PM-1. Heterologous expression of the npdG and npdI genes showed that they were involved in 2,4-DNP degradation. Sequence analyses of both the NDFRs and the HTIIs revealed conserved domains which may be involved in binding of NADPH or F420. Phylogenetic analyses of the NDFRs showed that they represent a new group in the family of F420-dependent NADPH reductases. Phylogenetic analyses of the HTIIs revealed that they form an additional group in the family of F420-dependent glucose-6-phosphate dehydrogenases and F420-dependent N5,N10-methylenetetrahydromethanopterin reductases. Thus, the NDFRs and the HTIIs may each represent a novel group of F420-dependent enzymes involved in catabolism.  相似文献   
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