Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.17 (lysozyme)
 21,489 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

It is known that protein attachment to surfaces depends sensitively upon the local structure and environment of the binding sites at the nanometer scale. Using nanografting and reversal nanografting, both atomic force microscopy (AFM)-based lithography techniques, protein binding sites with well-defined local environments are designed and engineered with nanometer precision. Three proteins, goat antibiotin immunoglobulin G (IgG), lysozyme, and rabbit immunoglobulin G, are immobilized onto these engineered surfaces. Strong dependence on the dimension and spatial distribution of protein binding sites are revealed in antibody recognition, covalent attachment via primary amine residues and surface-bound aldehyde groups. This investigation indicates that AFM-based nanolithography enables the production of protein nanostructures, and more importantly, protein-surface interactions at a molecular level can be regulated by changing the binding domains and their local environment at nanometer scale.
ACS Nano 2008 Nov 25
PMID:A nanoengineering approach for investigation and regulation of protein immobilization. 1920 5

Hen egg white lysozyme acted as the sole reducing agent and catalyzed the formation of silver nanoparticles in the presence of light. Stable silver colloids formed after mixing lysozyme and silver acetate in methanol and the resulting nanoparticles were concentrated and transferred to aqueous solution without any significant changes in physical properties. Activity and antimicrobial assays demonstrated lysozyme-silver nanoparticles retained the hydrolase function of the enzyme and were effective in inhibiting growth of Escherichia coli, Staphylococcus aureus, Bacillus anthracis, and Candida albicans. Remarkably, lysozyme-silver nanoparticles demonstrated a strong antimicrobial effect against silver-resistant Proteus mirabilis strains and a recombinant E. coli strain containing the multiple antibiotic- and silver-resistant plasmid, pMG101. Results of toxicological studies using human epidermal keratinocytes revealed that lysozyme-silver nanoparticles are nontoxic at concentrations sufficient to inhibit microbial growth. Overall, the ability of lysozyme to assemble silver nanoparticles in a one-step reaction offers a simple and environmentally friendly approach to form stable colloids of nontoxic silver nanoparticles that combine the antimicrobial properties of lysozyme and silver. The results expand the functionality of nanomaterials for biological systems and represent a novel antimicrobial composite for potential aseptics and therapeutic use in the future.
ACS Nano 2009 Apr 28
PMID:Lysozyme catalyzes the formation of antimicrobial silver nanoparticles. 1934 24

Electrochemical (EC) quartz crystal microbalance with dissipation monitoring (ECQCM-D) is a new and powerful technique for the in situ study of adsorption phenomena, e.g., as a function of the potential of the substrate. When titanium (Ti) is employed as the substrate, its oxidation behavior needs to be taken into account. Ti is always covered with a native oxide layer that can grow by, e.g., thermal oxidation or under anodic polarization. For biomolecular adsorption studies on oxidized Ti under applied potential, a stable oxide layer is desired in order to be able to distinguish the adsorption phenomena and the oxide growth. Therefore, the oxidation of thermally evaporated Ti films was investigated in phosphate-buffered saline by means of ECQCM-D, using a specially designed EC flow cell. Upon stepping the potential applied to Ti up to 2.6 V vs standard hydrogen electrode (SHE), a fast increase of the mass was observed initially for each potential step, evolving slowly to an asymptotic mass change after several hours. The oxide layer thickness increased as a quasi-linear function of the oxidation potential for potentials up to 1.8 V vs SHE. The growth rate of the oxide was around 2.5-3 nm/V. No changes in the dissipation shift were observed for potentials up to 1.8 V vs SHE. The composition of the oxide layer was analyzed by X-ray photoelectron spectroscopy (XPS). It was mainly composed of TiO(2), with a small percentage of suboxides (TiO and Ti(2)O(3)) primarily at the inner metal/oxide interface. The amount of TiO(2) increased, and that of TiO and Ti(2)O(3) decreased, with increasing oxidation potential. For each oxidation potential, the calculated thickness obtained from ECQCM-D correlated well with the thickness obtained by XPS depth profiling. A procedure to prepare Ti samples with a stable oxide layer was successfully established for investigations on the influence of an electric field on the adsorption of biomolecules. As such, the effect of an applied potential on the adsorption behavior of lysozyme on oxidized Ti was investigated. It was observed that the adsorption of lysozyme on oxidized Ti was not influenced by the applied potential.
ACS Appl Mater Interfaces 2009 Feb
PMID:In situ control of the oxide layer on thermally evaporated titanium and lysozyme adsorption by means of electrochemical quartz crystal microbalance with dissipation. 2035 17

The use of nanobubbles, the common surfactant sodium dodecyl sulfate (SDS), and nanobubbles in combination with SDS as cleaning agents to remove lysozyme from the solid-liquid interface has been investigated using a quartz crystal microbalance on both hydrophobic and hydrophilic surfaces. On the hydrophobic surface, significant amounts of protein remained on the surface after 10 cycles of nanobubble treatment for 10 s periods in phosphate buffer. The cleaning efficiency of SDS was far superior and was shown to remove approximately 90% of the protein. The use of nanobubbles in combination with SDS failed to improve the cleaning efficiency further. On the other hand, lysozyme on the hydrophilic surface cannot be removed effectively by either 10 cycles of cleaning with nanobubbles or 10 cycles of cleaning with SDS. Nevertheless, the protein can be removed completely after 6 cycles of cleaning with nanobubbles in combination with SDS.
ACS Appl Mater Interfaces 2009 Feb
PMID:Improved cleaning of hydrophilic protein-coated surfaces using the combination of Nanobubbles and SDS. 2035 40

We report on the first use of carbon-nanotube-based films to produce crystals of proteins. The crystals nucleate on the surface of the film. The difficulty of crystallizing proteins is a major bottleneck in the determination of the structure and function of biological molecules. The crystallization of two model proteins and two medically relevant proteins was studied. Quantitative data on the crystallization times of the model protein lysozyme are also presented. Two types of nanotube films, one made with the surfactant Triton X-100 (TX-100) and one with gelatin, were tested. Both induce nucleation of the crystal phase at supersaturations at which the protein solution would otherwise remain clear; however, the gelatin-based film induced nucleation down to much lower supersaturations for the two model proteins with which it was used. It appears that the interactions of gelatin with the protein molecules are particularly favorable to nucleation. Crystals of the C1 domain of the human cardiac myosin-binding protein-C that diffracted to a resolution of 1.6 A were obtained on the TX-100 film. This is far superior to the best crystals obtained using standard techniques, which only diffracted to 3.0 A. Thus, both of our nanotube-based films are very promising candidates for future work on crystallizing difficult-to-crystallize target proteins.
ACS Appl Mater Interfaces 2009 Jun
PMID:Carbon-nanotube-based materials for protein crystallization. 2035 14

We report a method for the synthesis of antimicrobial coatings on medical instruments that combines the bacteriolytic activity of lysozyme and the biocidal properties of silver nanoparticles. Colloidal suspensions of lysozyme and silver nanoparticles were electrophoretically deposited onto the surface of stainless steel surgical blades and needles. Electrodeposited films firmly adhered to stainless steel surfaces even after extensive washing and retained the hydrolytic properties of lysozyme. The antimicrobial efficacy of coatings was tested by using blades and needles in an in vitro lytic assay designed to mimic the normal application of the instruments. Coated blades and needles were used to make incisions and punctures, respectively, into agarose infused with bacterial cells. Cell lysis was seen at the contact sites, demonstrating that antimicrobial activity is transferred into the media, as well as retained on the surface of the blades and needles. Blade coatings also exhibited antimicrobial activity against a range of bacterial species. In particular, coated blades demonstrated potent bactericidal activity, reducing cell viability by at least 3 log within 1.5 h for Klebsiella pneumoniae, Bacillus anthracis Sterne, and Bacillus subtilis and within 3 h for Staphylococcus aureus and Acinetobacter baylyi. The results confirmed that complex antimicrobial coatings can be created using facile methods for silver nanoparticle synthesis and electrodeposition.
ACS Appl Mater Interfaces 2009 Jul
PMID:Hybrid antimicrobial enzyme and silver nanoparticle coatings for medical instruments. 2035 60

Superparamagnetic nanoparticles are of great current interest for biomedical applications in both diagnostics and treatment. Magnetic nanoparticles (MNP) can be manipulated by magnetic fields, so that when functionalized, they can be used for the purification and separation of biomolecules and even whole cells. Here we report combining the separation capabilities of MNPs with the functional (binding) capability of molecularly imprinted polymers. Albumin- creatinine-, lysozyme-, and urea-imprinted polymer nanoparticles were synthesized from poly(ethylene-co-ethylene alcohol) via phase inversion, with both target molecules and hydrophobic magnetic nanoparticles mixed within the polymer solution. Several ethylene:ethylene alcohol mole ratios were studied. The rebinding capacities for those three target molecules varied from 0.76 +/- 0.02 to 5.97 +/- 0.04 mg/g of molecularly imprinted magnetic nanoparticles. Lastly, the composite nanoparticles were used for separation and sensing of template molecules (e.g., human serum albumin) in real samples (urine) and results were compared with a commercial ARCHITECT ci 8200 system.
ACS Appl Mater Interfaces 2010 Jun
PMID:Synthesis of magnetic molecularly imprinted poly(ethylene-co-vinyl alcohol) nanoparticles and their uses in the extraction and sensing of target molecules in urine. 2052 74

Oligomeric assemblies formed from a variety of disease-associated peptides and proteins have been strongly associated with toxicity in many neurodegenerative conditions, such as Alzheimer's disease. The precise nature of the toxic agents, however, remains still to be established. We show that prefibrillar aggregates of E22G (arctic) variant of the Abeta(1-42) peptide bind strongly to 1-anilinonaphthalene 8-sulfonate and that changes in this property correlate significantly with changes in its cytotoxicity. Moreover, we show that this phenomenon is common to other amyloid systems, such as wild-type Abeta(1-42), the I59T variant of human lysozyme and an SH3 domain. These findings are consistent with a model in which the exposure of hydrophobic surfaces as a result of the aggregation of misfolded species is a crucial and common feature of these pathogenic species.
ACS Chem Biol 2010 Aug 20
PMID:ANS binding reveals common features of cytotoxic amyloid species. 2055 Jan 30

Lysozymes contain a disproportionately large fraction of cationic residues, and are thereby attracted toward the negatively charged surface of bacterial targets. Importantly, this conserved biophysical property may inhibit lysozyme antibacterial function during acute and chronic infections. A mouse model of acute pulmonary Pseudomonas aeruginosa infection demonstrated that anionic biopolymers accumulate to high concentrations in the infected lung, and the presence of these species correlates with decreased endogenous lysozyme activity. To develop antibacterial enzymes designed specifically to be used as antimicrobial agents in the infected airway, the electrostatic potential of human lysozyme (hLYS) was remodeled by protein engineering. A novel, high-throughput screen was implemented to functionally interrogate combinatorial libraries of charge-engineered hLYS proteins, and variants with improved bactericidal activity were isolated and characterized in detail. These studies illustrate a general mechanism by which polyanions inhibit lysozyme function, and they are the first direct demonstration that decreasing hLYS's net cationic character improves its antibacterial activity in the presence of disease-associated biopolymers. In addition to avoiding electrostatic sequestration, at least one charge-engineered variant also kills bacteria more rapidly in the absence of inhibitory biopolymers; this observation supports a novel hypothesis that tuning the cellular affinity of peptidoglycan hydrolases may be a general strategy for improving kinetics of bacterial killing.
ACS Chem Biol 2010 Sep 17
PMID:Enhanced antimicrobial activity of engineered human lysozyme. 2060 27

Polyurethane (PU) with zwitterionic side chains has been prepared to resist nonspecific adsorption of proteins. First, dihydroxy-terminated poly(2-(dimethylamino)ethyl methacrylate) (PDEM(OH)(2)) is synthesized by free radical polymerization with 3-mercapto-1,2-propanediol as the chain transfer agent, which polyadds with diisocyanate to yield a PU with PDEM side chains. Such side chains are zwitterionized by 1,3-propane sultone. Proton nuclear magnetic resonance spectroscopy ((1)H NMR), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS) show that the zwitterionic side chains are incorporated into the PU. Thermal analysis demonstrates the thermal stability is greatly affected by the content of the side chains. By use of quartz crystal microbalance with dissipation (QCM-D), we have investigated the adsorption of fibrinogen, bovine serum albumin, and lysozyme on a surface constructed by such a PU. It shows the PU has a controllable protein resistance depending on the content of the zwitterionic side chains.
ACS Appl Mater Interfaces 2011 Feb
PMID:Preparation of polyurethane with zwitterionic side chains and their protein resistance. 2122 76


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