Term
what are the three molecules that interconvert between each other? |
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Definition
glucose6p-->fructose6p-->mannose6p |
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Term
what is an essential feature of the glycoprotein structure? |
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Definition
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Term
what is the structure of N-linked glycoproteins? |
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Definition
two N-acetylglucosamines (GlcNac) and three mannoses. |
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Term
what is the function of phosphoglucose isomerase? |
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Definition
converts glucose to fructose |
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Term
what is the function of phosphomannose mutase? |
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Definition
converts mannose 6 phosphate to fructose 6p |
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Term
what is aldose-ketose isomerization? |
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Definition
moves double within same molecule w/o net change in the oxidation state of the molecule. |
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Term
what is type 1 CDG associated with? |
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Definition
deficiency in phosphomannose mutase 2 |
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Term
what is type 1b CDG characterized by? |
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Definition
phosphomannose isomerase deficiency |
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Term
what does the basic defect of CDGS appear to be |
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Definition
synthesis of processing of N-linked oligosaccharides |
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Term
this is used as a sensitive indicator to identify CDG |
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Definition
glycosylation state of serum transferrin |
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Term
what is an indicated by transferrin |
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Definition
altered electrophoretic mobility of unusual isoforms |
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Term
what is present in O-linked glycoproteins |
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Definition
fucose, sialic acid, and N-acetyl galactosamine |
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Term
GDP mannose is converted to GDP fucose releasing what |
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Definition
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Term
decarboxylation of of UDP-glucuronic acid yields what (UDP Glu->UDP Glucuronic->?) |
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Definition
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Term
what is UDP xylose necessary? |
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Definition
synthesis of proteoglycans |
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Term
this leads to formation of amino sugars and sialic acids |
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Definition
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Term
the A allele encodes what? |
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Definition
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Term
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Definition
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Term
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Definition
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Term
symptoms of hereditary fructose intolerance |
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Definition
hypoglycemia, hyposphosphatemia, hypermangnesemia |
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Term
In hereditary fructose intolerance, what is interconverted? |
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Definition
fructose 6p and glucose 6p interconvert |
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Term
deficiency in aldolase B leads to? |
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Definition
low ATP and phosphate depletion |
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Term
dietary fructose is converted to fructose 1p by what enzyme |
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Definition
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Term
how is fructose intolerance treated? |
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Definition
complete elimination of all sources sugar |
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Term
essential fructosuria is a deficiency in |
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Definition
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Term
consumption of fructose from an individual with aldolase B deficiency results in |
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Definition
accumulation of fructose 1-phosphate and depletion of ATP |
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Term
when glucose concentration in the lens is high, this enzyme converts some of it to sorbitol |
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Definition
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Term
sorbitol can be converted to fructose by what |
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Definition
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Term
accumulation of sorbitol in the eye leads to increased osmolarity of the lens. what does this cause |
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Definition
aggregation and denaturation of the crystallins |
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Term
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Definition
changes in the structural organization of crystallins w/increased light scattering |
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Term
when aldolase reductase is greater than the activity of polyol dehydrogenase, what does that cause |
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Definition
accumulation of sorbitol leading to catarcts |
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Term
when aldolase reductase is greater than the activity of polyol dehydrogenase, what does that cause |
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Definition
accumulation of sorbitol leading to catarcts |
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Term
interconversion of glucose and galactose requires formation of |
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Definition
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Term
deficiency in this enzyme causes a relatively mild form of galactosemia |
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Definition
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Term
how does excess galactose play a role in central nervous system damage? |
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Definition
galactose is reduced to galactitol causing accumulation in the lens. |
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Term
deficiency of this enzyme causes severe galactosemia |
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Definition
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Term
this enzyme deficiency can cause both forms of galactosemia |
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Definition
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Term
what forms glucuronic acid |
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Definition
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Term
what is the major difference between UDP glucose and UDP glucuronic |
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Definition
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Term
what is the central step in bilirubin exretion? |
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Definition
conjugation w/glucuronic acid by UDP-glucuronyltransferase |
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Term
congenital familial non hemolytic jaundice results from a deficiency of |
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Definition
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Term
can humans convert glucuronic acid to ascorbic acid? |
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Definition
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Term
what is essential for sorting of the enzymes to lysosomes |
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Definition
addition of a phosphate group to mannose in position 6 |
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Term
what is mucolipidosis II (I cell) disease characterized by? |
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Definition
deficiency in N-acetylglucosamine phosphotransferase |
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Term
what happens to fibroblasts in I cell disease |
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Definition
dense inclusion bodies-lack of lysosome function |
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Term
what is mucolipidosis III due to? |
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Definition
reduced GlcNac phosphotransferase |
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Term
what is the function of phosphomannose isomerase |
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Definition
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Term
what does the Hgene code for in the ABO blood group systems? |
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Definition
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