Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.26 (invertase)
 4,927 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Developing and germinating lima bean (Phaseolus lunatus var Cangreen) seeds were used for testing the sucrose synthase pathway, to examine the competition for uridine diphosphate (UDP) and pyrophosphate (PPi), and to identify adaptive and maintenance-type enzymes in glycolysis and gluconeogenesis. In developing seeds, sucrose breakdown was dominated by the sucrose synthase pathway; but in the seedling embryos, both the sucrose synthase pathway and acid invertase were active. UDPase activity was low and seemingly insufficient to compete for UDP during sucrose metabolism in seed development or germination. In contrast, both an acid and alkaline pyrophosphatase were active in seed development and germination. The set of adaptive enzymes identified in developing seeds were sucrose synthase, PPi-dependent phosphofructokinase, plus acid and alkaline pyrophosphatase; and, the adaptive enzymes identified in germinating seeds included the same set of enzymes plus acid invertase. The set of maintenance enzymes identified during development, in the dry seed, and during germination were UDP-glucopyrophosphorylase, neutral invertase, ATP and UTP-dependent fructokinase, glucokinase, phosphoglucomutase, ATP and UTP-dependent phosphofructokinase and sucrose-P synthase.
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PMID:Sucrose metabolism in lima bean seeds. 1666 72

A plasma membrane-enriched fraction was isolated from various tissues of developing lima bean seedlings, Phaseolus lunatus var Cangreen, to study beta-1,3-glucan synthase activity changes. All tissues contained an active beta-glucan synthase, including the cotyledons that will be senescent in mature lima bean plants. Young primary leaves exhibited a very active beta-glucan synthase; but this activity dropped markedly, about fivefold, as the leaves gained weight and became photosynthetic. Some tissues, such as the hypocotyl and young stem, exhibited an increase in beta-glucan synthase activity as the tissues were growing and a decrease as the growth rate slowed. Roots exhibited a high activity early in development that only decreased slightly, about 30%, as root growth increased. Surprisingly the senescent cotyledons contained an activity equivalent to some other tissues that was maintained over our measurement time of 21 days. Perhaps this callose synthesis activity is related to translocation processes as the cotyledons transfer their reserves to the growing seedling. We concluded that beta-glucan synthase was not a good indicator of sink strength in these lima bean tissues. The plasma membrane fractions also were tested for other enzymes that might be present because an electron microscope study revealed a low contamination by other types of membranes. The membrane fractions had low but detectable activities of sucrose synthase, UDPglucose pyrophosphorylase, UDPase, alkaline invertase, and a general phosphatase; but these enzymes exhibited no consistent pattern(s) of activity change with plant development.
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PMID:Changes in beta-1,3-Glucan Synthase Activity in Developing Lima Bean Plants. 1666 36