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)

Groups of rabbits were exposed to chlorides of nickel, cadmium, copper, and cobalt at concentrations ranging from 0.2 to 0.6 mg/m3 (as metal) for 4-6 weeks (5 days/week, 6 hr/day). Activity of lysozyme (muramidase) in lavage fluid, in alveolar macrophages, and in culture medium from macrophages incubated at 37 degrees C for 1 and 20 hr was estimated using the lyso-plate technique, agar plates with heat-killed Micrococcus lysodeikticus. In the nickel-exposed rabbits lysozyme activity in the mucous membrane from the left main bronchus was also estimated. Following nickel exposure the lysozyme level was significantly decreased in lavage fluid, macrophages, and in culture medium from incubated macrophages but remained unchanged in the mucous membrane. After exposure to cadmium, copper, and cobalt, lysozyme levels increased or were unchanged.
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PMID:Lysozyme levels in rabbit lung after inhalation of nickel, cadmium, cobalt, and copper chlorides. 674 35

The N-acetylglutamate deacetylase (EC 3.5.1.-) from Pseudomonas aeruginosa, strain PAO1, was purified 15,000-fold to electrophoretic homogeneity. The enzyme was distinct from acetylornithinase and formylglutamate hydrolase. Its molecular weight was estimated to be 90,000 by gel filtration and by sedimentation in sucrose gradients. Electrophoresis in sodium-dodecyl sulphate gels gave a single band corresponding to a molecular weight of 44,000. N-Acetylglutamate deacetylase was L-specific and showed no peptidase activity. Among 17 N-acetyl-L-amino acids tested as substrates, N-acetyl-L-glutamine, N-acetyl-L-methionine and N-acetylglycine were hydrolysed at 20% of the rate of N-acetyl-L-glutamate whereas other N-acetyl-L-amino acids were deacetylated at a rate of less than 10%. The catalytic activity depended on Co2+. The Km of the enzyme with respect to N-acetylglutamate was 1.43 mM. Preparation of spheroplasts with lysozyme in the presence of 0.2 M-MgCl2 led to the release of 80% of the enzyme activity from the cells, indicating the periplasmic localization of N-acetylglutamate deacetylase. Its localization in the periplasmic space explains the inability of P. aeruginosa argA mutants to grow on N-acetylglutamate, which is utilized by the wild-type as a carbon and nitrogen source.
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PMID:Properties and localization of N-acetylglutamate deacetylase from Pseudomonas aeruginosa. 680 Nov 90

The interaction between hen egg-white lysozyme and Cu(II) or Co(II) cations has been studied by dilatometry, equilibrium dialysis-differential refractometry and viscometry at different metal cation concentrations. Delta V isotherms in copper and cobalt solutions have been obtained from dilatometry. Preferential adsorption parameters and specific viscosity have been determined from refractometric and viscosimetric measurements. It has been observed that this interaction produces structural alterations in lysozyme. The magnitude of these conformational changes depends on the metal ion and protein concentration. The results obtained using the three techniques are in good agreement.
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PMID:Dilatometric, refractometric and viscometric study of lysozyme-cation interaction. 732 52

A Spheron-base affinity sorbent containing Concanavalin A (Con A) groupings has been synthesized. Con A was immobilized via the formation of a ternary complex with a stationary ligand (tetrafunctional) triethylene tetramine) and cobalt(III) ions. The inertness of cobalt(III) provided strong binding of Con A to the matrix. The sorbent was tested for the ability to absorb proteins (albumin, lysozyme, heparin, and ribonuclease) and used the isolation of glucosaminidase from the proteolytic complex of the fungus Geotrichum candidum. The purified enzyme was characterized biochemically.
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PMID:[An affinity chromatography sorbent containing concanavalin A groups immobilized by complex formation with cobalt]. 747 34

Monitoring of microbial DNA in soils by dot blot hybridization and PCR analysis is a useful technique for gaining insight into the survival and impact of genetically modified micro-organisms released in the environment. Most methods of DNA isolation from soils require a large number of purification steps rendering them unsuitable for quantitative analysis of multiple samples. Here we describe a very rapid method for the isolation and purification of multiple samples of soil DNA that can be used directly for dot blot hybridization and PCR analysis. Soil DNA extracts are prepared by lysozyme/SDS treatment at pH 9.0 and purified by ammonium acetate precipitation and Sephadex G50 gel filtration. In a practical application of this method, sandy soil samples were seeded with Alcaligenes eutrophus cells and exposed to high temperature (42 degrees C) or desiccation. As a result, the number of culturable A. eutrophus cells which could be recovered from the soil samples quickly declined. However, the concentration of a marker gene encoding resistance to cadmium, cobalt and zinc (czc) remained unaltered.
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PMID:Rapid method for purification of soil DNA for hybridization and PCR analysis. 826 Nov 67

Six men who had undergone hip replacements for degenerative joint disease or trauma subsequently had radical prostatectomies or cystoprostatectomies with bilateral pelvic lymph node dissections for adenocarcinoma of the prostate or transitional cell carcinoma of the urinary bladder. The hip prostheses implanted in three patients were known to contain cobalt-chromium alloy and titanium. The pelvic lymph nodes ipsilateral to the hip prosthesis in five patients and the bilateral pelvic nodes in the only patient with bilateral hip prosthesis had dark brown or black cut surfaces. These lymph nodes did not contain carcinoma but showed florid sinus histiocytosis characterized by large polygonal histiocytes filling and expanding sinuses and interfollicular regions. The foamy histiocytes contained cobalt-chromium and titanium microparticles by light microscopy, ultrastructure, and energy-dispersive x-ray microanalysis. The lymph nodes uninvolved by the histiocytic reaction lacked the heavy metal microparticles. Four cases were found to have a small number of polyethylene particles, which might have contributed to the histiocytic response. By immunohistochemistry, the foamy cells displayed immunoreactivity for lysozyme, alpha-1-antitrypsin, alpha-1-antichymotrypsin, and cathepsin D, providing additional support for their histiocytic derivation. To our knowledge, this is the first time that microparticles of cobalt-chromium and titanium that migrate from hip prostheses to pelvic lymph nodes have been shown to elicit a distinctive type of florid sinus histiocytosis. Pathologists should be aware of this characteristic foreign-body tissue response to avoid confusion with other types of sinus histiocytosis or with metastatic carcinoma.
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PMID:Sinus histiocytosis of pelvic lymph nodes after hip replacement. A histiocytic proliferation induced by cobalt-chromium and titanium. 827 30

The chromatographic selectivity of the immobilized chelate system, 1,4,7-triazocyclononane (tacn), complexed with the borderline metal ions Cu2+, Cr3+, Mn2+, Co2+, Zn2+, and Ni2+ has been investigated with hen egg white lysozyme, horse heart cytochrome c, and horse skeletal muscle myoglobin, as well as proteins present in partially fractionated preparations of human plasma. The effects of ionic strength and pH of the loading and elution buffers on protein selectivities of these new immobilized metal ion affinity chromatographic (IMAC) systems have been examined. The results confirm that immobilized Mn;pl-tacn sorbents exhibit a novel type of IMAC behavior with proteins. In particular, the chromatographic properties of these immobilized M(n+)-tacn ligand systems were significantly different compared to the IMAC behavior observed with other types of immobilized tri- and tetradentate chelating ligands, such as iminodiacetic acid, O-phosphoserine, or nitrilotriacetic acid, when complexed with borderline metal ions. The experimental results have consequently been evaluated in terms of the additional contributions to the interactive processes mediated by effects other than solely the conventional lone pair Lewis soft acid-Lewis soft base coordination interactions, typically found for the IMAC of proteins with borderline and soft metal ions, such as Cu2+ or Ni2+.
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PMID:Protein selectivity with immobilized metal ion-tacn sorbents: chromatographic studies with human serum proteins and several other globular proteins. 944 41

Site-specific photocleavage of hen egg lysozyme and bovine serum albumin (BSA) by N-(l-phenylalanine)-4-(1-pyrene)butyramide (Py-Phe) is reported. Py-Phe binds to lysozyme and BSA with binding constants 2.2 +/- 0.3 x 10(5) M-1 and 6.5 +/- 0.4 x 10(7) M-1, respectively. Photocleavage of lysozyme and BSA was achieved with high specificity when a mixture of protein, Py-Phe, and an electron acceptor, cobalt(III) hexammine (CoHA), was irradiated at 344 nm. Quantum yields of photocleavage of lysozyme and BSA were 0.26 and 0.0021, respectively. No protein cleavage was observed in the absence of Py-Phe, CoHA, or light. N-terminal sequencing of the protein fragments indicated a single cleavage site of lysozyme between Trp-108 and Val-109, whereas the cleavage of BSA was found to be between Leu-346 and Arg-347. Laser flash photolysis studies of a mixture of protein, Py-Phe, and CoHA showed a strong transient with absorption centered at approximately 460 nm, corresponding to pyrene cation radical. Quenching of the singlet excited state of Py-Phe by CoHA followed by the reaction of the resulting pyrenyl cation radical with the protein backbone may be responsible for the protein cleavage. The high specificity of photocleavage may be valuable in targeting specific sites of proteins with small molecules.
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PMID:Photochemical protease: site-specific photocleavage of hen egg lysozyme and bovine serum albumin. 972 8

Lacrimal fluid plays a very significant role in maintaining proper functions of conjuctivas, cornea and eyelids. The fluid is secreted by the main lacrimal gland and additional glands. It produces the so called preocular lacrimal film. A number of clinical tests, such as Chirmer's tests I and II, break-up-time (BUT), lysozyme, and flow tests are used in quantitative and qualitative analyses, as well as in the determination of the lacrimal film stability. The aim of work was to utilize these in assessing the lacrimal secretion and the lacrimal film stability in workers chronically exposed to petroleum derivatives. Fifty three workers from departments of acetobenzene, benzene and butadiene, phenol and acetone, sewage waters, asphalt oxidas, polyethylene and polypropylene, were eligible for the study (group I). During previous examinations, acquired disorders in colour perception were diagnosed in all the subjects by means of the Mansuella-Fansworth 100-Hue test. The age range was 25 to 56 years, with a mediane of 44.1 years +/- 6.5. Mean duration of employment was 22 years (SD +/- 8.25). The control group (group II) was composed of 28 men aged between 24 and 60 years with a median of 42.7 years +/- 6.3, never employed under conditions of exposure to toxic chemicals. On the right eye of each subject Schirmer's test was performed after instilling into the conjunctival sac 1-2 drops of Alcain solution according to Whitcher. Five min following anesthesia of the conjunctival sac, a standardised belt of blotting-paper with colour dampness markers Vidisic (Dr Mann Pharma GMBH, Germany) was placed in the vicinity of the external angle of the eye. After 5 min the degree of the belt dampness was measured in millimetres. After 30 min the break-up-time test was performed on the left eye. Fluorescein was released to conjunctival sac from a sterile belt of blotting-paper (Haag-Strait Co.). A slit lamp with cobalt filter was used to calculate time (in sec) that elapsed between opening of the lid slit and the first symptom of breaking-up the lacrimal film. The results obtained were presented in the form of arithmetic means and standard deviation values +/- SD. Schirmer's test was 13.40 +/- 7.43 mm in group 1, and 22.54 +/- 8.25 mm in the control group, mean values differed significantly, p < 0.01. Lacrimal film break-up-time was 16.30 +/- 6.19 sec in group 1, and 31.48 +/- 7.96 sec in the control group, mean values differed significantly, p < 0.01. In persons chronically exposed to petroleum derivatives, statistically significant decrease in lacrimal secretion, as well as shortening of lacrimal film break-up-time were found when compared with the control group.
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PMID:[Lacrimation disorders in workers chronically exposed to petroleum derivatives]. 1039 14

The host inflammatory response to particulate wear debris has been implicated as a principal cause of osteolysis and aseptic loosening following total joint arthroplasty. While it has long been assumed that this inflammatory response is mediated solely by a chronic process, there has been evidence to suggest that an acute response to particulate debris may be important in initiating the chronic response. We studied the in vitro and in vivo acute inflammatory responses mediated by polymorphonuclear leukocytes (PMNs) to both retrieved particulate from a catastrophically failed uncemented metal-backed acetabular component and to commercially pure particulate (polyethylene, cobalt-chrome, and titanium). Isolated, nonactivated human PMNs in vitro exhibited both a dose- and time-dependent degranulation response to opsonized particulate debris, as evidenced by release of both specific (increased lysozyme activity) and azurophilic (increased beta-glucuronidase activity) granule contents. In the rat subcutaneous pouch model in vivo, PMNs were recruited within 3-6 h after exposure to particulate debris and were noted to phagocytize particulate and subsequently degranulate, as evidenced by increased beta-glucuronidase and PMN-specific myeloperoxidase (azurophilic granule enzymes) activities. This response peaked within the first 6 h and gradually declined by 24 h. The results of this study demonstrate the presence of an acute inflammatory response mediated by PMNs both in vitro and in vivo to particulate debris, which may be important in the sequence of events that lead to the macrophage-dominated chronic inflammatory process culminating in osteolysis and aseptic loosening of total joint arthroplasties.
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PMID:In vitro and in vivo activation of polymorphonuclear leukocytes in response to particulate debris. 1055 58


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