Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P04179 (MnSOD)
 2,777 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Superoxide dismutase (SOD) from extracts of anaerobically maintained Bacteroides thetaiotaomicron was a dimer of equally sized 23,000-molecular-weight monomers joined noncovalently. A preparation with a specific activity of 1,200 U/mg contained 1.1 g-atom of Fe, 0.6 g-atom of Zn, and less than 0.05 g-atom of Mn per mol of dimer. The apoprotein, prepared by dialysis of iron-SOD in 5 M guanidinium chloride-20 mM 8-hydroxyquinoline, had no superoxide-scavenging activity when renatured without exogenous metal. Enzymatic activity was restored to the denatured apoprotein by dialysis against either 1 mM Fe(NH4)2 or 1 mM MnCl2 in 20 mM Tris (pH 7.0). The Fe-reconstituted enzyme and the native enzyme were inhibited approximately 50% by 0.2 mM NaN3, whereas the Mn-reconstituted enzyme was inhibited 60% by 10 mM NaN3. Aeration of the anaerobic cells resulted in a fourfold induction of an azide-resistant SOD. The enzyme (43,000 molecular weight) isolated from aerated cells was a dimer of equally sized subunits. The metal content was 1.0 g-atom of Mn, 0.55 g-atom of Fe, and 0.3 g-atom of Zn per mol of dimer. Enzymatic activity of the denatured apoprotein from this enzyme was also restored on addition of either iron or manganese. The constitutive Fe-SOD and the O2-induced Mn-SOD, tested alone and in combination, migrated identically on acrylamide gels, had similar amino acid compositions, and had alanine as the sole N-terminal amino acid. These data are consistent with the synthesis of a single apoprotein in either anaerobically maintained or oxygenated cells. We have observed a similar phenomenon with SOD from Bacteroides fragilis (E. M. Gregory, Arch. Biochem. Biophys. 238:83-89, 1985).
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PMID:Isolation and reconstitution of iron- and manganese-containing superoxide dismutases from Bacteroides thetaiotaomicron. 370 Mar 36

Phenotypic alterations induced by the cytokinin 6-benzylaminopurine in cell suspensions of Nicotiana plumbaginifolia were studied at the level of the NH(2)-terminal sequence of the constituent proteins. Total protein extracts were separated by classical two-dimensional PAGE, and the proteins were recovered by electroblotting onto support materials allowing direct gas-phase sequence analysis of the immobilized proteins. The systems used consist of an efficient electrotransfer buffer (50 mM Tris borate, pH 8.3) in combination with either glass-fiber sheets to which poly(4-vinyl-N-methylpyridinium iodide) is adsorbed or with membranes of polyvinylidene difluoride. The former is an improved version of our previously reported Polybrene-coated glass-fiber sheets and was found to be at least twice as efficient as the polyvinylidene difluoride blots. Thirteen proteins were selected for analysis. They were either induced, repressed, or independent of cytokinin. Ten proteins yielded a sequence, ranging from 10 to 38 residues. Three of the studied Nicotiana proteins show a degree of homology higher than 85% with the amino acid sequences of other eukaryotic proteins-triose-phosphate isomerase, Mn superoxide dismutase, and (1,3)-beta-glucanase. The latter enzyme was repressed by the plant hormone. This study demonstrates that proteins associated with phenotypic variations in cells can now be sequenced by a straightforward procedure involving two-dimensional gel separation of total cellular proteins, recovery by electroblotting, and gas-phase sequence analysis of the immobilized proteins.
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PMID:Alterations in the phenotype of plant cells studied by NH(2)-terminal amino acid-sequence analysis of proteins electroblotted from two-dimensional gel-separated total extracts. 1657 10