Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0272170 (SDS)
 50,377 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The amide content of neocarzinostatin (NCS), an antitumor protein, has been determined by analysing asparagine and glutamine in the Pronase-aminopeptidase M digests of tetra-S-carboxymethyl-NCS and carboxyl-modified NCS (modified with a water-soluble carbodiimide and [14C]glycine methyl ester). Preneocarzinostatin (PRE) was separated and purified from a crude NCS preparation by CM-cellulose column chromatography. PRE was found to contain one mole less asparagine than NCS, and asparagine was deamidated to aspartic acid in PRE. A time-dependent conversion of NCS to PRE at pH 3.2 at 4 degrees or in 0.1 M acetic acid at 26 degrees was studied in two ways; first, by quantitative determination of NCS and PRE by CM-cellulose column chromatography and second, by following the release of free NH3 during dialysis in an air-tight container. Within experimental error, PRE was indistinguishable from NCS in amino acid content after acid hydrolysis, as well as in apparent molecular weight as determined by SDS-disc gel electrophoresis (10% acrylamide), and N- and C-terminal amino acid residues. Both NCS and PRE shared a common antigenicity as determined by Ouchterlony's agar diffusion method. Only a slight difference between the two in electrophoresis on a cellulose acetate membrane and on a peptide map of the tryptic digest was demonstrated. PRE, however, was completely devoid of biological activity. In addition to the chromatographic difference, a conformational difference was observed by CD spectroscopy, namely, an apparently looser structure of PRE was indicated by the shallowness of the trough in the 240-265 nm region. This interpretation was supported by the finding that digestions by Pronase were more extensive with PRE than with NCS. These results indicate an important role of the single asparagine residue (Asn 83) of NCS in the biological activity, which is evidently governed by the conformation.
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PMID:Spontaneous deamidation of a protein antibiotic, neocarzinostatin, at weakly acidic pH. Conversion to a homologous inactive preneocarzinostatin due to change of asparagine 83 to aspartic acid 83 accompanied by conformational and biological alterations. 1 34

Lysophospholipase [EC 3.1.1.5] was solubilized from the cells of Vibrio parahaemolyticus with Triton X-100 and purified by the following procedure; precipitation with ammonium sulfate, acid treatment and ion exchange column chromatography using DEAE-cellulose, DEAE-Sephadex A-50, and CM-cellulose, successively. The purified preparation was shown to be homogeneous by polyacrylamide gel disk electrophoresis. The isoelectric point of the enzyme was found to be around pH 3.64 by isoelectric focusing electrophoresis, and its molecular weight was estimated to be 89,000 at pH 7.6 by gel filtration on Sephadex G-200. The minimal molecular weight (15,000) was found at pH 3 by gel filtration on Sephadex G-100 and also by SDS-polyacrylamide disk electrophoresis. The enzyme hydrolyzed 1-acyl-GPC, 1-acyl-GPE, 2-acyl-GPE, and lysocardiolipin but did not attack monoacylglycerol, triacylglycerol, or phosphatidylcholine at all. The enzyme activity required no bivalent cations, and was unaffected by reagents specific to SH-groups, although it was inhibited by Hg2+. The enzyme activity was completely inhibited by preincubation with diisopropylfluorophosphate. The enzyme lost its activity on preincubation with either 1% SDS or 8 M urea at 37 degrees C for 30 min, but the activity lost with urea was recovered by dialysis against distilled water.
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PMID:Purification of lysophospholipase of Vibrio parahaemolyticus and its properties. 2 76

A moderately halophilic Acinetobacter sp., capable of producing dextrinogenic amylase, was isolated from sea-sands. Maximum enzyme production was obtained when the bacterium was cultivated aerobically in media containing 1 to 2M NaCl or 1M KCl. Two kinds of amylase, amylases I and II were purified from the culture filtrate to an electrophoretically homogenous state by glycogen-complex formation, DEAE-Sephadex A-50 chromatography, and Sephadex G-200 gel filtration. Both enzymes had maximal activity at pH 7.0 in 0.2 to 0.6 M NaCl or KCl at 50 to 55 degrees C. The activities were lost by dialysis against distilled water. Molecular weights for amylases I and II were estimated to be 55 000 and 65 000 respectively by SDS-gel electrophoresis. The action pattern on amylose, soluble starch, and glycogen showed that the products were maltose and maltotriose.
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PMID:Purification and properties of amylase produced by a moderately halophilic Acinetobacter sp. 3 May 30

A cellulase component of Avicelase type was obtained from Driselase, a commercial enzyme preparation from a wood-rotting fungus Irpex lacteus (Polyporus tulipiferae). It showed a single band on SDS-polyacrylamide electrophoresis. The amino acid composition of this cellulase resembled those of cellulase components of endo-type from the same fungus. However, it produced exclusively cellobiose from CMC as well as from water-insoluble celluloses such as Avicel or cotton at earlier stages of hydrolysis. In addition, the hydrolysis of CMC practically stopped after an initial rapid stage. The cellulase showed a strong synergistic action with an endo-cellulase of higher randomness (typical CMCase-type) in the hydrolysis of CMC as well as Avicel. In contrast to cellotriose and -tetraose, cellopentaose and -hexaose were attacked very rapidly, and only cellobiose was produced. These results suggest that the cellulase is an exo-type component. However, it mutarotated the products from cellopentaitol in the same direction as endo-cellulases. it represented a relatively large portion of the total cellulase activity, and may play an important role in the degradation of native cellulose in vivo.
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PMID:Purification and properties of an exo-cellulase of Avicelase type from a wood-rotting fungus, Irpex lacteus (Polyporus tulipiferae). 3 75

A detailed description and stepwise evaluation of a procedure that can be used to obtain myelin basic protein (BP) from whole brain is presented. The procedure involved the 0.001 MHC1 extraction of whole brain pre-treated in a sequential manner with chloroform-methanol (2:1 v/v), acetone, and deionized water. This is followed by a precipitation of the extract at pH 9.0, and gel filtration of the supernatant in 0.01 M HC1. Yields of canine and porcine BP and their disc gel evaluations are presented at several key points in the procedure. The final products possessed a high degree of homogeneity when examined on SDS gels stained with commonly used protein stains. When compared with six SDS-gel marker-protein standards, the canine and porcine final products had mobilities that correspond to an apparent molecular weight of 18,5000 +/- 5%. Quantitative binding of 125I-labeled canine and porcine BPs with standardized rabbit anti-BP antisera gave comparable results. Immunoelectrophoretic and immunodiffusion examinations demonstrated single components and complete identity. The canine and porcine BP's also reacted fully with syngeneic anti-BP antisera raised in Lewis-strain rats. The canine BP was tested for encephalitogenicity in Lewis-strain rats and found to be comparable to rat BP in producing experimental allergic encephalomyelitis.
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PMID:An evaluation of a procedure for the isolation of myelin basic protein (BP). 6 Jul 58

Clinical and pathological studies have revealed that in multiple sclerosis (MS) the involvement of the optic tracts is much more frequent than that of the olfactory tracts. To investigate the possible reasons for this difference in involvement of these two adjacent structures, both containing a central type myelin, we have studied optic and olfactory tracts obtained at autopsy from 7 adult males ranging in age from 54 to 64 years. White matter from the frontal poles of the same individuals was used for reference. These tissues were compared with respect to the relative content of a) water, b) soluble proteins, c) 2',3'-cyclic nucleotide 3'-phosphohydrolase (CNP) activity, and d) immunologically precipitable basic protein (BP). Homogenates from these tissues were further compared by disc gel electrophoresis in two systems; phenolformic acid-water and SDS-urea gels. Results indicate that while the optic tracts and the frontal pole white matter were similar with respect to their water, total protein content and BP content, the optic tracts had lower CNP activity than the frontal poles. The olfactory tracts contained more water and less BP and the CNP activity of these structures was lower than that of the frontal pole white matter. Assuming the CNP activity and the BP content are true measures of the total myelin content of a given tissue, it appears that olfactory tracts have smaller amounts of myelin. On the other hand, the optic tracts contain only half as much CNP-activity with a disproportionately greater amount of BP. The possible significance of these findings is discussed.
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PMID:Biochemical and immunological studies with human optic and olfactory tracts. 8 54

The i-active substance was isolated from i adult and I int erythrocyte membranes by butanol-water extraction and was purified by SDS-gel filtration and thin layer chromatography of peracetylated samples. The i-active substances from both types of erythrocytes showed also IF activity. In antigen isolated from i adult red cells the IF activity was lower than i activity. On the other hand, the antigen of I int red cells showed higher IF than i activity. The chemical characterization of isolated antigens indicated their glycosphingolipid character.
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PMID:Isolation and partial characterization of I antigen from I adult erythrocyte membranes. 8 32

The Bacillus cereus protein has been obtained from culture fluid in homogenic form as indicated by SDS-disc electrophoresis and immunodiffusion not described before. The protein has a molecular weight of 100000 daltons. Purification was accomplished by the following steps: (1) removal of ballast nitrous components with DE-32 cellulose at pH 7.2; (2) removal of the proteins from the culture filtrate (deluted four times by water) with DE-32 cellulose at pH 8.6; (3) elution by 0.005 M tris-HCl buffer at pH 7.0 containing 0.5 M NaCl; (4) column rechromatography on DE-32 cellulose at pH 8.6. The isolated protein was identified as a vascular permeability factor acording to the bluing zone in rabbit skin tests or to the bluing lung tissue in mice.
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PMID:The bacillus cereus toxin: isolation of permeability factor. 11 38

A lipophilic derivative of neocarzinostatin (NCS), an antitumor antibiotic, was prepared by reaction with a synthetic water-soluble polymer, [(styrene)1 approximately 3-(maleic acid 4 approximately 7/anhydride 1)]. The reaction was carried out at pH 8.6 for 3 h and aimed at modifying the two nonessential amino groups (alpha-amino of Ala-1, epsilon-amino of Lys-20). The NCS-polystyrene (SMANCS) was purified on a column of Sephadex G-100 in 0.05 M ammonium bicarbonate and the main product was obtained as a single peak. The elemental analysis showed an increased C and a decreased N content. U.v. and i.r. absorption spectra for SMANCS showed the presence of styrene. SDS-acrylamide gel electrophoresis at pH 8.5 and the decreased N content suggested a molecular weight of about 25 000, indicating the numbers of polymers conjugated to be about six units, two of which were found attached to the two amino groups. SMANCS was soluble in organic solvents, in contrast to NCS, and in water. SMANCS exhibited increased chemical and biological stability and appeared to possess similar in vitro biological activity.
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PMID:A lipophilic derivative of neocarzinostatin. A polymer conjugation of an antitumor protein antibiotic. 15 71

It is well established that active sodium-ion transport and water flow across isolated toad bladder are increased by antidiuretic hormone (ADH) and by cAMP. These agents were also observed in previous studies to cause changes in the amount of radioactive phosphate in a specific protein in the toad bladder. This protein, found by SDS-polyacrylamide gel electrophoresis of toad bladder epithelial preparations, had an apparent molecular weight of 49,000 daltons. In the present study, a correlation was found between the ability of a variety of substances to affect the amount of radioactive phosphate in this 40,000-dalton protein and their ability to alter the rate of sodium transport. Thus several agents (ADH, cAMP, theophylline, adenine, prostaglandin E1, and Mn Cl-2) caused a decrease in the amount of radioactive phosphate in the 49,000-dalton protein and also stimulated active sodium transport across the bladder. Conversely, ZnCl-2 produced an increase in the amount of radioactive phosphate in this protein and an inhibition of sodium transport. With each of these agents, the time-course of change in phosphorylation of this protein was, in general, similar to that for sodium transport. A second phosphoprotein, with an apparent molecular weight of about 42,000 daltons, showed changes in parallel with, but less extensive than, those observed in the 49,000 dalton protein. There was no consistent relationship between changes in level of phosphorylation of either in the 49,000- or 42,000- dalton protein and changes in osmotic water permeability. The results are compatible with the possibility that regulation by ADH and by cAMP of sodium transport in the toad bladder epithelium may be mediated through regulation of the amount of phosphate in a specific protein.
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PMID:Regulation of protein phosphorylation and sodium transport in toad bladder. 16 89


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