Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
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Drug
Enzyme
Compound
Query: UMLS:C0038187 (
starvation
)
24,951
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
A number of lysosomal enzymes are secreted from Tetrahymena pyriformis during growth and during
starvation
. The secretion is energy-dependent and kinetically different among hydrolases. On the basis of the secretion kinetics under
starvation
conditions, Tetrahymena hydrolases can be separated into three classes. The first group containing acid phosphatase, beta-glucosidase and
alpha-galactosidase
, are secreted slowly. Within this group about 4% of the initial cellular activity is released per hour. The second group of enzymes, including alpha-glucosidase, alpha-mannosidase and beta-galactosidase, exhibit moderate secretion (11-15% of the initial cellular activity per hour). The third group, N-acetyl-beta-hexosaminidase, has the highest rate of secretion (22% of the initial cellular activity per hour). N-Acetyl-beta-hexosaminidase shows a continuous increase in overall activity during
starvation
, which is completely blocked by adding cycloheximide; its secretion is also suppressed. Such involvement of enzyme biosynthesis was not seen in the first and second groups. Furthermore, treatment with weak bases caused inhibited secretion of differing degree among acid phosphatase (group I), alpha-glucosidase (group II) and N-acetyl-beta-hexosaminidase (group III).
...
PMID:Secretion heterogeneity of lysosomal enzymes in Tetrahymena pyriformis. 295 37
Activities of several phosphohydrolases are significantly enhanced when cells of the inositol-requiring yeast, Saccharomyces uvarum ATCC 9080, are deprived of inositol. This effect is most pronounced for the external acid phosphatase and cannot be explained simply by limitation of cellular growth, because
starvation
for vitamins or sulphate has no effect on acid phosphatase activities. Excessive secretion of acid phosphatase by spheroplasts prepared from inositol-deficient cells is greatly reduced when the spheroplast medium is supplemented with inositol and is immediately suppressed by the addition of cycloheximide. These results together with data obtained from experiments with whole cells, employing cycloheximide and actinomycin D, point to a regulatory effect of inositol limitation at the level of transcription. The external enzymes beta-D-fructofuranosidase,
alpha-D-galactosidase
and L-asparaginase, and the vacuolar enzyme carboxypeptidase Y are not affected by inositol deficiency indicating that inositol deficiency has no general effect on protein secretion.
...
PMID:The effect of myo-inositol deficiency on phosphatases of yeast. 608 32