Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:2.4.1.14 (SPS)
813 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A method for product analysis that eliminates a problematic step in the radiometric sucrose-phosphate synthase assay is described. The method uses chromatography on a boronate-derivatized high-performance liquid chromatography column to separate the labeled product, [14C]sucrose phosphate, from unreacted uridine 5'-diphosphate-[14C]glucose (UDP-Glc). Direct separation of these compounds eliminates the need for treatment of the reaction mixtures with alkaline phosphatase, thereby avoiding the problem of high background caused by contaminating phosphodiesterase activity in alkaline phosphatase preparations. The method presented in this paper can be applied to many UDP-Glc requiring enzymes; here we show its use for determining the activities of sucrose-phosphate synthase, sucrose synthase, and uridine diphosphate-glucose pyrophosphorylase in plant extracts.
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PMID:A high-performance liquid chromatography-based radiometric assay for sucrose-phosphate synthase and other UDP-glucose requiring enzymes. 183 Jul 27

2-week isocaloric modifications in the dietary ratio of polyunsaturated/saturated fatty acids (P/S) alters intestinal transport in rats. This study was undertaken to test the hypotheses that (1) the fatty acid composition of a nutritionally adequate diet in early life has lasting consequences for active and passive intestinal transport processes; and (2) early life feeding experiences with diets of varying fatty acid composition influence the intestines' ability to adaptively up- or down-regulate intestinal transport in later life. Female Sprague-Dawley rats were weaned onto S or P and were maintained on these diets for 2, 10 or 12 weeks. An in vitro uptake technique was used in which the bulk phase was vigorously stirred to reduce the effective resistance of the intestinal unstirred water layer. P decreased and S increased the uptake of glucose, and this effect was progressive from 2 to 12 weeks. Switching from a P to an S diet decreased jejunal but increased ileal uptake of glucose, whereas switching from an S to a P diet was associated with a decline in both the jejunal and the ileal uptake of glucose. The ileal uptake of galactose increased as the animals grew on either P or S. Switching from P to S resulted in a decline in ileal uptake of galactose, whereas the opposite effect was observed when switching from S to P. The effect of feeding P or S on hexose uptake was influenced by the animals' dietary history: ileal glucose and galactose uptake was lower in animals fed P at an early age (PSP) than in animals fed P for the first time in later life (SSP). Jejunal glucose and galactose uptake was also lower in animals fed S at an early age (SPS) than in those fed S for the first time in later life (PPS). The alterations in the uptake of long-chain saturated and unsaturated fatty acids and cholesterol did not progress with longer periods of feeding, and in the jejunum, lipid uptake did not change when switching from P to S or S to P. Early feeding with P (PSP vs. SSP) was associated with lower jejunal uptake of 18:3 and lower ileal uptake of 12:0, whereas previous feeding with S (SPS vs. PPS) was associated with lower ileal uptake of cholesterol. The changes in uptake of hexoses and lipids was not explained by differences in the animals' food consumption, body or intestinal weight or mucosal surface area.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Evidence for critical-period programming of intestinal transport function: variations in the dietary ratio of polyunsaturated to saturated fatty acids alters ontogeny of the rat intestine. 291 55

Two basal media, containing the ingredients found in common in both SPS (BBL) and TSN (BBL) media and in the previously described media of Schaedler et al. (1965) and Starr et al (1971), but minus antibiotics, were selected as the most suitable for the enumeration of Clostridium perfringens spores in a model system. These media were also used to study the influence of the presence of glucose, xylose, or ribose in various concentrations (0, 0.01, 0.1, and 1.0%) on colony morphology and spore recovery. As the sugar concentration in the basal agar medium increased, the colonies of all the test organisms also increased in size, and more of the black colonies became white in color. At the 1.0% sugar level, glucose permitted only white colony development, whereas the pentoses were completely inhibitory. Both pour plates and most-probable-number tubes were inoculated with the spores of several strains of C. perfringens and incubated at 20, 30, 37, and 45 C for 24, 48, and 72 h. Statistical analyses of the enumeration data indicated, at the 99% confidence level, that a Trypticase(BBL)-yeast extract-glucose-sulfite-iron agar gave maximal population estimates at 37 C in 72 h.
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PMID:Evaluation of media, time and temperature of incubation, and method of enumeration of several strains fo Clostridium perfringens spores. 436 58

A cDNA clone encoding a sucrose-phosphate synthase from sugar beet (BvSPS 1) has been isolated by screening a tap root-specific cDNA library using a heterologous SPS cDNA from spinach. The 3635 bp sugar beet cDNA codes for a 1045 amino acid polypeptide with a predicted molecular mass of 118 kDa. The deduced amino acid sequence of sugar beet SPS shows homologies with SPS from maize (71% identity) and spinach (77% identity). Genomic Southern blot analysis suggests that BvSPS 1 is a low-copy-number gene. RNA blot analysis of sink and source leaves, root and tap root tissue shows that SPS 1 is expressed in an organ-specific manner, being predominantly active in tap root. Incubation of detached leaves of sugar beet in light in glucose-containing media leads to an accumulation of the SPS transcript, while sucrose feeding reduces the steady-state level of the mRNA.
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PMID:Cloning and expression analysis of sucrose-phosphate synthase from sugar beet (Beta vulgaris L.). 777 61

The present study was undertaken to explore endogenous sleep factors isolated from 48-72 h sleep deprived (SD) male Tupaia belangeri chinensis (TBC). Only drink ad libitum (10% glucose) was available within 24 h before collection of urine. Controlled "clean" urinary samples were pooled and stored at 20 C. Fraction I-V from the urine were determined after ultrafiltration and Sephadex-G15. Amino-acid analysis of each fraction was automatically done by a 835 Amino-acid Analyzer, respectively. Bioassay was performed in 40 adult rabbits weighing 2.5-3.5 kg of either sex. Experiments were undertaken via the mesodiencephalic intraventricular infusion. Results show that S2C (Fraction-III) (50 micrograms/rabbit, i.c.v.) exhibited significant delta-enhancing effect compared to the controls. Further purification was done with Sephadex G-25 and Sephadex LH-20. The more purified S4B (50 micrograms/rabbit, i.c.v.) also exhibited significant delta-enhancing effect compared to the controls. The amino-acid analysis of Fraction-III revealed that the compositional contents of S2C and S4B are different from what have been known with Factor S, DSIP and SPS.
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PMID:[Studies on the isolation of endogenous sleep factors from Tupaia Belangeri Chinensis (TBC) after sleep deprivation]. 808 74

The uridine diphosphate-glucose (UDP-Glc) binding domain of sucrose-phosphate synthase (SPS) was identified by overexpressing part of the gene from spinach (Spinacia oleracea). Degenerate oligonucleotide primers corresponding to two tryptic peptides common to both the full-length 120-kD SPS subunit and an 82-kD form that photoaffinity labeled with 5-azidouridine diphosphate-glucose (5-N3UDP-Glc) were used in a polymerase chain reaction to isolate a partial cDNA clone. Comparison of the deduced amino acid sequence of spinach SPS with the sequences of potato sucrose synthase showed that the partial cDNA included one region that was highly conserved between the proteins. Expression of the partial cDNA clone of SPS in Escherichia coli produced a 26-kD fusion protein that photoaffinity labeled with 5-N3UDP-Glc. Photoaffinity labeling of the 26-kD fusion protein was specific, indicating that this portion of the SPS protein harbors the UDP-Glc-binding domain. Isolation of a modified peptide from the photolabeled protein provided tentative identification of amino acid residues that make up the uridine-binding domain of SPS.
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PMID:Identification of the uridine-binding domain of sucrose-phosphate synthase. Expression of a region of the protein that photoaffinity labels with 5-azidouridine diphosphate-glucose. 810 11

In this study, we purified and characterized tetra- and triglycosyl glycolipids (GL-1 and GL-2, respectively) from two different colonial forms of Thermus scotoductus X-1, from T. filiformis Tok4 A2, and from T. oshimai SPS-11. Acid hydrolysis of the purified glycolipids liberated, in addition to the expected long-chain fatty acids, two components which were identified by gas chromatography-mass spectrometry as 16-methylheptadecane-1,2-diol and 15-methylheptadecane-1,2-diol. Fast atom bombardment mass spectrometry of the intact glycolipids indicated that a major proportion consisted of components with glycan head groups linked to long-chain 1,2-diols rather than to glycerol, although in all cases glycerol-linked compounds containing similar glycan head groups were also present. As in other Thermus strains, the polar head group of GL-1 from T. filiformis Tok4 A2 and from T. scotoductus X-1 colony type t2 was a glucosylgalactosyl-(N-acyl)glucosaminylglucosyl moiety. However, GL-2 from T. scotoductus X-1 colony type t1 and from T. oshimai SPS-11 was a truncated analog which lacked the nonreducing terminal glucose. Long-chain 1,2-diols have been previously reported in the polar lipids of Thermomicrobium roseum and (possibly) Chloroflexus aurantiacus, but to our knowledge, this is the first report of their detection in other bacteria and the first account of the structural determination of long-chain diol-linked glycolipids.
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PMID:Characterization of novel long-chain 1,2-diols in Thermus species and demonstration that Thermus strains contain both glycerol-linked and diol-linked glycolipids. 932 66

Early during fruit ripening in kiwifruit (Actinidia deliciosa var. deliciosa [A. Chev.], C.F. Liang and A.R. Ferguson cv. Hayward), starch is broken down to sucrose and hexose sugars. Concomitantly, sucrose-phosphate synthase (SPS, EC 2.3.1.14) activity measured with saturating substrate increased, suggesting that SPS is induced in response to a higher requirement for sucrose synthesis. A 2584 bp long partial cDNA clone encoding SPS was isolated from ripening kiwifruit. cDNA fragments encoding the 5' end were isolated by PCR, and sequencing revealed at least four closely related (> 96% identity) mRNAs expressed early in kiwifruit ripening. Southern hybridisations in a diploid relative of kiwifruit, Actinidia chinensis (Planch.) var. chinensis, were consistent with the presence of a small gene family. Western analysis indicated a 125 kDa SPS protein present in all tissues of A. chitensis at all stages of development. Steady-state levels of SPS mRNA in A. chinensis increased near fruit maturity as net starch degradation began on the vine, and increased again during ethylene treatment of fruit after harvest. After removal from ethylene SPS transcript levels decreased, only to increase again as fruit moved into the climacteric and starch breakdown was completed. Exposure to low temperatures also caused an increase in SPS transcript level. These results indicate that SPS mRNA increases in kiwifruit in response to the presence of new substrate sourced from starch degradation, in response to ethylene and in response to low temperature.
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PMID:Sucrose-phosphate synthase steady-state mRNA increases in ripening kiwifruit. 952 Feb 77

Water stress stimulates sucrose synthesis and inhibits starch synthesis in wild-type tubers. Antisense and co-suppression potato transformants with decreased expression of sucrose-phosphate synthase (SPS) have been used to analyse the importance of SPS for the regulation of this water-stress induced change in partitioning. (i) In the absence of water stress, a 70-80% decrease in SPS activity led to a 30-50% inhibition of sucrose synthesis and a slight (10-20%) increase of starch synthesis in tuber discs in short-term labelling experiments with low concentrations of labelled glucose. Similar changes were seen in short-term labelling experiments with intact tubers attached to well-watered plants. Provided plants were grown with ample light and water, transformant tubers had a slightly lower water and sucrose content and a similar or even marginally higher starch content than wild-type tubers. (ii) When wild-type tuber slices were incubated with labelled glucose in the presence of mannitol to generate a moderate water deficit (between -0.12 and -0.72 MPa), there was a marked stimulation of sucrose synthesis and inhibition of starch synthesis. A similar stimulation was seen in labelling experiments with wild-type tubers that were attached to water-stressed wild-type plants. These changes were almost completely suppressed in transformants with a 70-80% reduction of SPS activity. (iii) Decreased irrigation led to an increase in the fraction of the dry-matter allocated to tubers in wild-type plants. This shift in allocation was prevented in transformants with reduced expression of SPS. (iv) The results show that operation of SPS and the sucrose cycle in growing potato tubers may lead to a marginal decrease in starch accumulation in non-stressed plants. However, SPS becomes a crucial factor in water-stressed plants because it is required for adaptive changes in tuber metabolism and whole plant allocation.
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PMID:Decreased expression of sucrose phosphate synthase strongly inhibits the water stress-induced synthesis of sucrose in growing potato tubers. 1047 59

Fruits of cv. Fortune mandarin were periodically harvested throughout the ripening period to evaluate changes in carbohydrate content and metabolism in flavedo tissue and to determine the potential role of carbohydrates in the tolerance of citrus fruit to chilling injury (CI). Sucrose showed little change in the flavedo during the season, but fructose and glucose increased, in nearly equal amounts, throughout the fall and winter, reaching a maximum in January. Starch levels were less abundant than soluble carbohydrates and rose continuously until March. Sucrose phosphate synthase (SPS; EC 4.1.14) activity decreased from December throughout ripening. Changes in sucrose synthase (SS; EC 2.4.1.13) and acid and alkaline invertase (Inv; EC 3.2.1.26) activities correlated with changes in the reducing sugars, but acid invertase was less active than the other sucrose-metabolizing enzymes. Carbohydrate changes in the flavedo of Fortune mandarins with fruit maturity appear not to be related to the chilling tolerance of fruits during cold storage.
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PMID:Carbohydrate content and metabolism as related to maturity and chilling sensitivity of cv. Fortune mandarins. 1055 19


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