Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.2.1.17 (lysozyme)
21,489 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We present a Raman and surface-enhanced Raman scattering (SERS) study of the following proteins containing S-S group(s): alpha chymotrypsin (alpha-CHT), insulin, lysozyme, oxytocin (OXT), Streptomyces subtilisin inhibitor (SSI), and trypsin inhibitor (STI). The SERS study is performed in order to understand the adsorption mechanism of the above-mentioned proteins on a colloidal silver surface. The SERS spectra presented here show bands associated mainly with aromatic amino acid vibrations. In addition, two distinct vibrations of the -C-S-S-C- fragment are observed in the Raman and SERS spectra, i.e., nu(SS) and nu(CS). The enhancement of the nu(SS) vibration in the SERS spectra yields evidence that the intact disulfide bridge(s) is (are) located near the silver surface. This finding is supported by the presence of the nu(CS) mode(s). The presence of nus(COO-) and nu(C-COO-) in the SERS spectra in the 1384-1399 cm(-1) and 909-939 cm(-1) regions, respectively, indicate that the negatively charged COO- groups (aspartic and glutamic acids) assist in the binding on the positively charged silver surface. The Raman amide I and III bands observed in the 1621-1633 and 1261-1289 cm(-1) ranges, respectively, indicate that the alpha-helical conformation is favored for binding to the surface over the random coil or beta-sheet conformations. In addition, the presence of the imino group of Trp and/or His indicates that these amino acid residues may also bind to the silver sol.
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PMID:Adsorption of S-S containing proteins on a colloidal silver surface studied by surface-enhanced Raman spectroscopy. 1552 14

Syringacin 4-A, a bacteriocin produced by Pseudomonas syrinagae 4-A, was obtained by induction with ultraviolet irradiation or mitomycin C. Approximately 1,000-fold purification of the bacteriocin was achieved by manganous chloride precipitation, differential centrifugation, and chromatography on hydroxyapatite columns. The purified syngacin was homogeneous on hydroxyapatite columns and sucrose density gradients; it also sedimented as a single entity in the analytical ultracentrifuge. The buoyant density of purified syringacin in cesium chloride was 1.294 g/ml. The sedimentation coefficient was calculated as 120S, and the diffusion coefficient was 6.49 x 10(-8) cm(2)/s. The molecular weight was calculated as 1.6 x 10(7) from physical data and 1.7 x 10(7) from biological data. The syringacin was composed of about 88.4% protein, 8.5% arabinose, 2.2% galacturonic acid, and 0.7% glucosamine. Amino acid analysis indicated a predominance of leucine (12.1%), aspartic acid (12.2%), and glutamic acid (12.7%). The ultraviolet spectrum showed a maximum absorbance peak at 276 nm. The syringacin was heat and alcohol sensitive, but resistant to trypsin, chymotrypsin, carboxypeptidase, Pronase, protease, lysozyme, steapsin, deoxyribonuclease, and ribonuclease. Maximum pH stability was between 5 and 8. Crude bacteriocin was stable at room temperature for at least a year, and purified material was stable for at least 3 months at 4 C.
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PMID:Purification and characterization of syringacin 4-A, a bacteriocin from pseudomonas syringae 4-A. 1582 74

Intergeneric protoplast fusion between Escherichia coli HB101 with pBR322 carrying the cloned o-(carboxymethyl)cellulase (CMCase) gene of Ruminococcus albus (Pro Leu Ap Km) and an anaerobic mutant strain, FEM29 (Trp His Ap Km), with dehydrodivanillin-degrading activity was performed in the presence of 40% polyvinyl alcohol 300 under aerobic and anaerobic conditions to transfer the cloned cellulase gene into the mutant. The mutant FEM29 had a unique property. When it was incubated in liquid medium with 1% glucose and sucrose, protoplasts could be produced autogenously and regenerated on the agar slant. E. coli spheroplasts formed from a plasmid-amplified overnight culture after 10 min of treatment with lysozyme (20 mug/ml) in a hypertonic solution (0.01 M Tris hydrochloride [pH 7.5], 0.4 M mannitol). Protoplast regeneration rates of FEM29 and HB101 were 30 and 83%, respectively, on the agar-yeast extract medium. Ap Km fusants were obtained at high frequency: 1.7 x 10 anaerobically and 8.2 x 10 aerobically. These fusants showed 23 to 57% of CMCase and dehydrodivanillin-degrading activities, respectively, as compared with parental strains. All the fusants isolated were gram-negative rods with main phenotypes such as urease and catalase activities as in HB101 and esterase and chymotrypsin activities as in FEM29. Southern hybridization experiments suggested that pBR322 with the cloned CMCase gene existed autonomously in the fusant cells. This is the first report describing transfer of pBR322 with a cloned cellulase gene into an anaerobic mutant by polyvinyl alcohol-mediated fusion with an E. coli spheroplast.
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PMID:Escherichia coli Spheroplast-Mediated Transfer of pBR322 Carrying the Cloned Ruminococcus albus Cellulase Gene into Anaerobic Mutant Strain FEM29 by Protoplast Fusion. 1634 43

Porphobilinogen oxygenase, skatole pyrrolooxygenase, and tryptophan pyrrolooxygenase were found in the different parts of germinating wheat (Triticum aestivum) grain seedlings. In the embryos of grains germinated for 24 hours, the activities of PBG oxygenase and skatole pyrrolooxygenase were inhibited by a labile inhibitor. Tryptophan pyrrolooxygenase activity was not inhibited. Embryos of grains germinated for 48 hours showed higher activities for the three enzymes. The latter were also present in the radicles and coleoptiles of 96-hour germinated wheat grains. A DEAE-cellulose analysis of a crude enzymic preparation from embryos allowed the separation of two molecular forms of the three pyrrolooxygenases. The more cationic forms of porphobilinogen oxygenase and skatole pyrrolooxygenase were associated with the inhibitor. This form of porphobilinogen oxygenase had allosteric kinetics while the more anionic form had Michaelis kinetics. Both forms of skatole pyrrolooxygenase had Michaelis kinetics. The activity of tryptophan pyrrolooxygenase was highest in seedling roots and was found to be inhibited in seedling young leaves. This enzyme oxidized tryptophanyl dipeptides, as well as a nonapeptide, to N-formylkynurenine-containing peptides. The pyrrolooxygenase also oxidized the tryptophanyl residues of lysozyme, chymotrypsin, and trypsin.
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PMID:Changes in the Activities of Pyrrolooxygenases during the Germination of Wheat Grains. 1666 14

Green turtle lysozyme purified from egg white was sequenced and analyzed its activity. Lysozyme was reduced and pyridylethylated or carboxymethylated to digest with trypsin, chymotrypsin and V8 protease. The peptides yielded were purified by RP-HPLC and sequenced. Every trypsin peptide was overlapped by chymotrypsin peptides and V8 protease peptides. This lysozyme is composed of 130 amino acids including an insertion of a Gly residue between 47 and 48 residues when compared with chicken lysozyme. The amino acid substitutions were found at subsites E and F. Namely Phe34, Arg45, Thr47, and Arg114 were replaced by Tyr, Tyr, Pro, and Asn, respectively. The time course using N-acetylglucosamine pentamer as a substrate showed a reduction of the rate constant of glycosidic cleavage and transglycosylation and increase of binding free energy for subsite E, which proved the contribution of amino acids mentioned above for substrate binding at subsites E and F.
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PMID:Amino acid sequence and activity of green turtle (Chelonia mydas) lysozyme. 1694 76

Alginate has potential as a matrix for controlled delivery of protein-based drugs that require site-specific long-term delivery. In the current work albumin, lysozyme and chymotrypsin were encapsulated into alginate microspheres using a novel method that involved soaking the microspheres in a protein-containing NaCl solution. This was followed by recrosslinking with calcium chloride. High pI proteins also appeared to physically crosslink the sodium alginate which resulted in more sustained release. Release was affected by the nature of the releasate solution. In TRIS buffered saline, the high pI proteins chymotrypsin and lysozyme showed sustained release lasting over 150 h. Release into 0.15% NaCl led to relatively constant release of lysozyme and chymotrypsin over more than 2000 h; reduction of the releasate volume lengthened the lysozyme release to greater than 8 months. Released lysozyme was shown to remain active for at least 16 days, in some cases with activity greater than 100% of the active control. This encapsulation technique can therefore be used to rapidly load alginate microspheres with proteins, with high isoelectric point proteins showing particular promise. Furthermore, the interactions between the high pI proteins and the alginate gel could potentially be exploited to generate new protein delivery systems.
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PMID:Extended release of high pI proteins from alginate microspheres via a novel encapsulation technique. 1715 84

Lysozyme has been tritiated by the free-radical interceptor method, which involves reaction of the carbon free radicals, resulting from gamma-irradiation of the lyophilized protein in a vacuum, with tritiated hydrogen sulfide. This technique resulted in a high yield of tritiated enzyme which was chromatographically indistinguishable from the native protein. To characterize this material with respect to its tritium distribution, it was first reduced, carboxymethylated, and digested with chymotrypsin. The peptides were separated and purified by ion exchange chromatography and electrophoresis and then analyzed to determine the specific activities of 78 of the 129 residues in the protein chain. The tritium was found to be broadly distributed, with only 12 residues apparently devoid of label. The relative specific activity, defined as the ratio of the specific activity of a given residue to the average specific activity for all residues of the same kind within the protein, did not exceed the value of 3.73 for isoleucine at position 88. A distinct spatial relationship is seen among the more heavily labeled residues when these results are related to the x-ray diffraction model of lysozyme. Thus, residues 16, 18, 19, 21, 23, 29, 31, and 32 may be grouped with 105, 110, 113, and 115; these highly labeled residues are close to a strongly hydrophobic region. Another heavily labeled area involves residues 50, 54, 57. 83, 84, and 88. In addition, residues 1 and 6 at the amino end of the chain are heavily labeled, as are 118, 121, and possibly 119 at the carboxyl end. This distribution of tritium appears to reflect the secondary free-radical distribution in the irradiated protein. These observations confirm previous indications that the secondary distribution is influenced by the conformation of the protein molecule.
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PMID:Tritiation of lysozyme by the free-radical interceptor method and determination of the tritium distribution among individual residues of the chromatographically homogeneous protein. 1738 79

The Author agrees in principle with the question/statement, but states also that an important qualification is needed within this question. In fact, it is not possible by the bottom up approach to find the conditions for the synthesis of our actual proteins-lysozyme, chymotrypsin or the like--however it is possible to show experimentally that co-oligopeptides chains of that length can be produced by prebiotic reactions. Considering such a synthesis, it is important to recall that proteins-and nucleic acids-are not simply polymers, but are co-polymers, and the kinetics and thermodynamics attending the synthesis of copolymers poses stringent constraints for the biogenesis and growth of specific sequences. Such constraints are examined and discussed.
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PMID:Question 3: the problem of macromolecular sequences: the forgotten stumbling block. 1763 17

The design, synthesis and properties of a new class of enzyme/DNA/inorganic nanobiomaterials are described here. DNA has been used to stabilize the enzymes intercalated in the galleries of the inorganic solid, alpha-Zr(iv) phosphate (alpha-Zr(HPO(4))(2).H(2)O, abbreviated as alpha-ZrP). Interestingly, the presence of DNA improved the activity and stability of the bound enzymes. Key studies leading to the current strategy are presented initially, and these are followed by more recent developments. Several enzymes and proteins, including horseradish peroxidase, lysozyme, glucose oxidase, chymotrypsin, bovine serum albumin, cytochrome c, met-hemoglobin and met-myoglobin are successfully intercalated in the galleries of alpha-ZrP, under benign ambient conditions (aqueous buffered solutions, at room temperature and neutral pH). These novel materials are characterized by XRD, SEM and TEM as well as by biochemical, calorimetric and spectroscopic methods. Spectroscopic studies (circular dichroism, CD), for example, indicated that co-intercalation of DNA improved the retention of bound enzyme structure. The activity was enhanced markedly (five-fold) when DNA is co-intercalated, when compared to the activity in the absence of DNA. Addition of DNA to the sample, after enzyme intercalation, did not make any improvements. Our hypothesis is that enzyme-DNA supramolecular complex binds to the solid and the unfavorable interactions between the enzyme and the solid are minimized. These novel nanobiocomposite materials provide a simple method for packaging DNA and aid in engineering more effective synthetic materials for gene/RNA-delivery and drug delivery applications.
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PMID:Novel enzyme/DNA/inorganic nanomaterials: a new generation of biocatalysts. 1804 9

Strain NRRL B-30745, isolated from chicken ceca and identified as Enterococcus durans, Enterococcus faecium, or Enterococcus hirae, was initially identified as antagonistic to Campylobacter jejuni. The isolate produced a 5,362-Da bacteriocin (enterocin) that inhibits the growth of Salmonella enterica serovar Enteritidis, S. enterica serovar Choleraesuis, S. enterica serovar Typhimurium, S. enterica serovar Gallinarum, Escherichia coli O157:H7, Yersinia enterocolitica, Citrobacter freundii, Klebsiella pneumoniae, Shigella dysenteriae, Pseudomonas aeruginosa, Proteus mirabilis, Morganella morganii, Staphylococcus aureus, Staphylococcus epidermidis, Listeria monocytogenes, Campylobacter jejuni, and 20 other Campylobacter species isolates. The enterocin, E-760, was isolated and purified by cation-exchange and hydrophobic-interaction chromatographies. The proteinaceous nature of purified enterocin E-760 was demonstrated upon treatment with various proteolytic enzymes. Specifically, the antimicrobial peptide was found to be sensitive to beta-chymotrypsin, proteinase K, and papain, while it was resistant to lysozyme and lipase. The enterocin demonstrated thermostability by retaining activity after 5 min at 100 degrees C and was stable at pH values between 5.0 and 8.7. However, activity was lost below pH 3.0 and above pH 9.5. Administration of enterocin E-760-treated feed significantly (P < 0.05) reduced the colonization of young broiler chicks experimentally challenged and colonized with two strains of C. jejuni by more than 8 log(10) CFU. Enterocin E-760 also significantly (P < 0.05) reduced the colonization of naturally acquired Campylobacter species in market age broiler chickens when administered in treated feed 4 days prior to analysis.
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PMID:Isolation and purification of enterocin E-760 with broad antimicrobial activity against gram-positive and gram-negative bacteria. 1808 39


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