Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.20 (alpha-glucosidase)
 4,237 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. Albumin activates human liver acid alpha-glucosidase (alpha-D-glucoside hydrolase, EC 3.2.1.20). From the Arrhenius plot, pH-dependence and Lineweaver-Burk plots it can be concluded that this activation is not only due to stabilisation of the enzyme, but also influences the enzymatic activity. It is proposed that for optimal functioning human liver acid alpha-glucosidase needs a protein environment. 2. Glycogen has a competitive inhibitory effect on the hydrolysis of 4-methylumbelliferyl-alpha-D-glucopyranoside, in contrast to maltose which exhibits a non-competitive type of inhibition. It is concluded that two catalytic sites exist, one for glycogen and one for maltose, while both sites influence each other. With glycogen as substrate a break in the Arrhenius plot is found. This is not the case when maltose is used as substrate. 3. The effect of antibody raised against human liver acid alpha-glucosidase on the activity of human liver acid alpha-glucosidase is studied. No corss-reacting material could be demonstrated in the liver of a patient with glycogen storage disease Type II (M. Pompe, acid alpha-glucosidase deficiency).
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PMID:Some properties of human liver acid alpha-glucosidase. 1 57

We wanted to investigate the origin of seminal plasma albumin and its relation to the male reproductive parameters. Semen samples from 916 men, under infertility assessment, were analysed according to guidelines of the World Health Organization. Seminal plasma constituents, i.e. albumin, markers of the epididymal (neutral alpha-glucosidase, NAG), prostatic (prostate-specific antigen, PSA, and zinc) and seminal vesicle function (fructose), as well as levels of reproductive hormones in plasma were measured. The sperm chromatin structure assay (SCSA) was applied on 267 of the 916 samples. A negative correlation was seen for seminal albumin and plasma follicle-stimulating hormone (r=-0.1, P=0.02) and a positive correlation for seminal albumin and serum inhibin B (r=0.2, P=0.004). Albumin exhibited positive correlations with the epididymal marker, NAG (r=0.5, P<0.001) and with the prostatic markers, PSA and zinc (r=0.1, P=0.001; r=0.2, P<0.001 respectively) as well as with age (r=0.2, P<0.001). A negative significant association was seen for seminal albumin and semen volume (beta=-0.60; 95% CI -0.80 to -0.30). The opposite trend was found regarding sperm concentration (beta=0.34; 95% CI 0.30-0.40), total sperm count (beta=0.30; 95% CI 0.20-0.40), and percentage morphologically normal spermatozoa (beta=0.70; 95% CI 0.10-1.0). No association was found between albumin and sperm motility, SCSA parameters, or fructose, the marker of seminal vesicles. Our results suggest testicular, epididymal and prostatic origin of seminal plasma albumin, in addition to the contribution from blood. This is the first study to demonstrate an association between seminal plasma albumin and sperm morphology. Further studies are needed to elucidate the role of seminal albumin in sperm morphology.
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PMID:Seminal plasma albumin: origin and relation to the male reproductive parameters. 1743 Apr 25