Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.36 (hyaluronidase)
 4,606 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The mechanism of albumin biosynthesis was studied in Morris hepatoma 5123tc in vivo and in hepatoma cell suspensions obtained by solubilizing the intercellular matrix with collagenase and hyaluronidase. In the in vivo experiments, L-[-14C]leucine was injected i.v. into rats bearing hepatomas in the muscles of both hind legs. After 14 min, tumors were removed and homogenized. A protein fraction quantitatively precipitable with antialbumin was isolated from the homogenate by acetone fractionation and precipitation with antiserum against serum albumin. This protein fraction was not homogeneous. With the use of 3 consecutive chromatographies on diethylaminoethyl cellulose, a very highly radioactive albumin-like protein could be separated from a large amount of only slightly radioactive albumin. In hepatoma cell suspensions incubated with L-[1-14C]leucine followed by a chase with excess nonradioactive L-leucine, radioactivity was incorporated first into the albumin-like protein and transferred thereafter into albumin, suggesting that albumin was synthesized via the albuminlike protein as precursor. In vivo, 1.8% of newly synthesized hepatoma protein was albumin or its precursor, compared with 1.2% in cell suspensions.
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PMID:Biosynthesis of albumin via a precursor protein in Morris hepatoma 5123tc. 18 40

The mechanism of the biosynthesis of albumin was studied in cell suspensions from rat liver. The cells were prepared by continuous perfusion of the liver in situ with 0.05% collagenase and 0.10% hyaluronidase and incubated under conditions optimized for the incorporation of amino acids into protein. Seven minutes after starting the incubation L-[1-14C]leucine was added, followed after 25 min by a 15 or 30-min chase with an 830-fold excess of non-radioactive L-leucine. Total protein, an albumin-like protein, and albumin were isolated from samples withdrawn immediately of total protein was found to remain constant after addition of the non-radioactive L-leucine, whereas that of the albumin-like protein decreased and that of albumin increased with incubation time. The increase in albumin radioactivity accounted for the decrease in radioactivity of the albumin-like protein, suggesting that the latter is a precursor of albumin. The precursor protein differed from albumin by an oligopeptide extension at the N-terminal end.
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PMID:Synthesis of albumin via a precursor protein in cell suspensions from rat liver. 126 47

Tibiae and humeri were removed from suckling rats at intervals of time after intraperitoneal injection of C(14)-L-phenylalanine, C(14)-L-leucine, S(35)-sulfate, or Ca(45) Cl(2). Autoradiograms of sections of the bones were prepared. Ca(45) was removed from sections treated with dilute acetic acid; neither the concentration of S(35) nor that of C(14) was thereby markedly decreased. The S(35) was removed from the demineralized sections on incubation in a solution of testicular hyaluronidase; the C(14) was not. These results are interpreted as indicating that most of the S(35) was present in the bones as chondroitin sulfate and that most of the C(14) in the bones was present as protein. In the epiphyses, the C(14) was initially concentrated in the proliferaing and hypertrophic chondrocytes, as was the S(35). Secretion of S(35)- and C(14)-labeled materials into the matrix followed. Thereafter, however, although the S(35)-labeled material (chondroitin sulfate) persisted in the matrix, albeit at a diminished concentration, and was incorporated into metaphyseal bone, the C(14)-labeled material (protein) was almost completely removed from the matrix. When rats were given repeated doses of 17-beta-estradiol benzoate so as to inhibit resorption of their metaphyses, repeated doses of S(35)-sulfate were discerned as strata of S(35) in their metaphyses. This was not the case if the rats received repeated doses of C(14)-L-phenylalanine or C(14)-L-leucine. On the basis of the results in these experiments it is suggested that although a portion of the chondroitin sulfate produced by the chondrocytes of the epiphyseal plate is retained and becomes part of the cores of metaphyseal spicules of bone, the protein of the proteinpolysaccharide is somehow removed before calcification of the cartilage ensues.
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PMID:Turnover of the organic matrix of cartilage and bone as visualized by autoradiography. 1401 80