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Sample records for immobilized penicillin acylase

  1. Radiation-induced polymerization for the immobilization of penicillin acylase

    SciTech Connect

    Boccu, E.; Carenza, M.; Lora, S.; Palma, G.; Veronese, F.M.

    1987-06-01

    The immobilization of Escherichia coli penicillin acylase was investigated by radiation-induced polymerization of 2-hydroxyethyl methacrylate at low temperature. A leak-proof composite that does not swell in water was obtained by adding the cross-linking agent trimethylolpropane trimethacrylate to the monomer-aqueous enzyme mixture. Penicillin acylase, which was immobilized with greater than 70% yield, possessed a higher Km value toward the substrate 6-nitro-3-phenylacetamidobenzoic acid than the free enzyme form (Km = 1.7 X 10(-5) and 1 X 10(-5) M, respectively). The structural stability of immobilized penicillin acylase, as assessed by heat, guanidinium chloride, and pH denaturation profiles, was very similar to that of the free-enzyme form, thus suggesting that penicillin acylase was entrapped in its native state into aqueous free spaces of the polymer matrix.

  2. Functionalized nanoporous silicas for the immobilization of penicillin acylase

    NASA Astrophysics Data System (ADS)

    Maria Chong, A. S.; Zhao, X. S.

    2004-10-01

    Nanoporous silica materials with uniform pore size and ordered structure have drawn growing interest of researchers since 1990s. A large-pore nanoporous material, SBA-15, was functionalized with organosilanes by co-condensation method in the presence of nonionic triblock copolymer P123 as a template under acidic conditions. The functionalization was demonstrated by using five organosilanes, namely 3-aminopropyltriethoxysilane (APTES), 3-mercaptopropyltrimethoxysilane (MPTMS), phenyltrimethoxysilane (PTMS), vinyltriethoxysilane (VTES), and 4-(triethoxysilyl)butyronitrile (TSBN), which modified the surface properties of the silica materials, enabling the materials to be a promising support for immobilization of biological molecules. The functionalized SBA-15 materials exhibited long-range ordering of two-dimensional hexagonal pore arrays of size ranging from 66 to 90 Å as demonstrated by small-angle X-ray scattering (SAXS), transmission electron microscopy (TEM), and physical adsorption techniques. A variety of organosilane density in the range of 0.5-2.6 mmol/g was achieved as revealed by elemental analysis and solid-state nuclear magnetic resonance (NMR) techniques. The functionalized materials displayed improved properties for immobilization of penicillin acylase (PA) in comparison with pure-silica SBA-15. Such improvement is believed to be due to the enhanced surface hydrophobicity and electrostatic interactions of the functional groups with the enzyme.

  3. Epoxy-functionalized mesostructured cellular foams as effective support for covalent immobilization of penicillin G acylase

    NASA Astrophysics Data System (ADS)

    Xue, Ping; Xu, Fang; Xu, Lidong

    2008-12-01

    The epoxy-functionalized mesoporous cellular foams (G-MCFs) with high specific surface area (˜400 m 2/g) and large-size mesopores (˜17 nm) were obtained by condensation of 3-glycidoxypropyltriethoxysilane (GPTS) and the surface silanol groups of mesoporous cellular foams (MCFs) and used as the support for immobilization of penicillin G acylase (PGA). The structural properties of G-MCF were characterized by FT-IR, N 2 adsorption, TG-DTA and 29Si MAS NMR. The studies indicated that the glycidoxypropyl groups were chemically bonded to the silicon atoms on the surface of MCF. The epoxy-functionalized mesoporous cellular foams can provide the microenvironments suitable for the immobilization of PGA, and the enzyme molecules could be immobilized covalently onto the G-MCF under mild conditions by reaction between the amino groups of the enzyme molecules and the epoxy groups on the surface of G-MCF. The PGA immobilized on G-MCF (PGA/G-MCF) exhibited the apparent activity of 1782 IU/g and 46.6% of activity recovery for hydrolyzing penicillin G potassium to produce 6-aminopenicillanic acid at 37 °C which were higher than that of PGA on pure silica MCF (1521 IU/g and 39.8%, respectively). The kinetic study also indicated that PGA immobilized on G-MCF has a Km of 2.1 × 10 -2 mol/L lower than that of PGA immobilized on the pure silica MCF (5.0 × 10 -2 mol/L). These may be attributed to the enhanced surface affinity between G-MCF support and the substrate molecules. Due to the covalent immobilization of PGA molecules on the surface of G-MCF, the immobilized PGA with considerable operational stability was achieved. The activity of PGA/G-MCF is still about 91.4% of its initial activity at the 10th cycle reuse while that of PGA/MCF only remains 41.5% of its initial activity at the same reuse numbers. In addition, the investigation results show the thermal stability and durability on acid or basic medium of PGA immobilized on G-MCF were improved remarkably.

  4. Genetic Modification of the Penicillin G Acylase Surface To Improve Its Reversible Immobilization on Ionic Exchangers▿

    PubMed Central

    Montes, Tamara; Grazú, Valeria; López-Gallego, Fernando; Hermoso, Juan A.; García, Jose L.; Manso, Isabel; Galán, Beatriz; González, Ramón; Fernández-Lafuente, Roberto; Guisán, José M.

    2007-01-01

    A new mutant of the industrial enzyme penicillin G acylase (PGA) from Escherichia coli has been designed to improve its reversible immobilization on anionic exchangers (DEAE- or polyethyleneimine [PEI]-coated agarose) by assembling eight new glutamic residues distributed homogeneously through the enzyme surface via site-directed mutagenesis. The mutant PGA is produced and processed in vivo as is the native enzyme. Moreover, it has a similar specific activity to and shows the same pH activity profile as native PGA; however, its isoelectric point decreased from 6.4 to 4.3. Although the new enzyme is adsorbed on both supports, the adsorption was even stronger when supports were coated with PEI, allowing us to improve the enzyme stability in organic cosolvents. The use of restrictive conditions during the enzyme adsorption on anionic exchangers (pH 5 and high ionic strength) permitted us to still further increase the strength of adsorption and the enzyme stability in the presence of organic solvents, suggesting that these conditions allow the penetration of the enzyme inside the polymeric beds, thus becoming fully covered with the polymer. After the enzyme inactivation, it can be desorbed to reuse the support. The possibility to improve the immobilization properties on an enzyme by site-directed mutagenesis of its surface opens a promising new scenario for enzyme engineering. PMID:17098917

  5. Electrically immobilized enzyme reactors: bioconversion of a charged substrate. Hydrolysis Of penicillin G by penicillin G acylase.

    PubMed

    Bossi, A; Guerrera, S; Righetti, P G

    1999-08-20

    The possibility of using the multicompartment immobilized enzyme reactor (MIER) in presence of a charged substrate is here explored. Penicillin G acylase is used to convert penicillin G (a free acid, with a pK of 2.6) into two charged products: phenyl acetic acid (PAA, with a pK of 4.2) and 6-aminopenicillanic acid (6-APA, a zwitterion with a pI of 3.6). The enzyme is trapped by an isoelectric mechanism in a chamber of the electrolyzer delimited by a pI 5.0 and a pI 9.0 amphoteric, isoelectric membranes. Under normal operating conditions (continuous substrate feeding in the presence of an electric field), only a low substrate conversion can be achieved, due to rapid electrophoretic transport of unreacted penicillin G out of the reaction chamber towards the anode. Excellent conversion rates (>96%) are obtained under a "doubly-discontinuous" operation mode: a time-lapse substrate feeding, accompanied by short times (4-8 min) of electric field interruption. The product of interest (6-APA, a precursor of semisynthetic penicillins), by virtue of its amphoteric nature, is trapped in a chamber delimited by a pI 3.5 membrane and a pI 5.5 membrane, adjacent to the reaction chamber on its anodic side. The other contaminant product (PAA) first accumulates in the same chamber and then progressively vacates it to collect in the anodic reservoir, leaving behind a pure 6-APA solution. In this operation mode, vanishing amounts of unreacted substrate (penicillin G) leave the reaction chamber to contaminate the adjacent, anodic chambers. A novel class of zwitterionic buffers is additionally reported, able to cover very thoroughly any pH value along the pH 3-10 interval: polymeric, zwitterionic buffers, synthesized with the principle of the Immobiline (acrylamido weak acids and bases) chemicals. Enhanced enzyme reactivity is found in this macromolecular buffers as compared to conventional ones. PMID:10397877

  6. [Phase transfer catalyzed bioconversion of penicillin G to 6-APA by immobilized penicillin acylase in recyclable aqueous two-phase systems with light/pH sensitive copolymers].

    PubMed

    Jin, Ke-ming; Cao, Xue-jun; Su, Jin; Ma, Li; Zhuang, Ying-ping; Chu, Ju; Zhang, Si-liang

    2008-03-01

    Immobilized penicillin acylase was used for bioconversion of penicillin PG into 6-APA in aqueous two-phase systems consisting of a light-sensitive polymer PNBC and a pH-sensitive polymer PADB. Partition coefficients of 6-APA was found to be about 5.78 in the presence of 1% NaCl. Enzyme kinetics showed that the reaction reached equilibrium at roughly 7 h. The 6-APA mole yields were 85.3% (pH 7.8, 20 degrees C), with about 20% increment as compared with the reaction of single aqueous phase buffer. The partition coefficient of PG (Na) varied scarcely, while that of the product, 6-APA and phenylacetic acid (PA) significantly varied due to Donnan effect of the phase systems and hydrophobicity of the products. The variation of the partition coefficients of the products also affected the bioconversion yield of the products. In the aqueous two-phase systems, the substrate, PG, the products of 6-APA and PA were biased in the top phase, while immobilized penicillin acylase at completely partitioned at the bottom. The substrate and PG entered the bottom phase, where it was catalyzed into 6-APA and PA and entered the top phase. Inhibition of the substrate and products was removed to result in improvement of the product yield, and the immobilized enzyme showed higher efficiency than the immobilized cells and occupied smaller volume. Compared with the free enzyme, immobilized enzyme had greater stability, longer life-time, and was completely partitioned in the bottom phase and recycle. Bioconversion in two-phase systems using immobilized penicillin acylase showed outstanding advantage. The light-sensitive copolymer forming aqueous two-phase systems could be recovered by laser radiation at 488 nm or filtered 450 nm light, while pH-sensitive polymer PADB could be recovered at the isoelectric point (pH 4.1). The recovery of the two copolymers was between 95% and 99%.

  7. Effect of internal diffusional restrictions on the hydrolysis of penicillin G: reactor performance and specific productivity of 6-APA with immobilized penicillin acylase.

    PubMed

    Valencia, Pedro; Flores, Sebastián; Wilson, Lorena; Illanes, Andrés

    2011-09-01

    A mathematical model that describes the heterogeneous reaction-diffusion process involved in penicillin G hydrolysis in a batch reactor with immobilized penicillin G acylase is presented. The reaction system includes the bulk liquid phase containing the dissolved substrate (and products) and the solid biocatalyst phase represented by glyoxyl-agarose spherical porous particles carrying the enzyme. The equations consider reaction and diffusion components that are presented in dimensionless form. This is a complex reaction system in which both products of reaction and the substrate itself are inhibitors. The simulation of a batch reactor performance with immobilized penicillin G acylase is presented and discussed for the internal diffusional restrictions impact on effectiveness and productivity. Increasing internal diffusional restrictions, through increasing catalyst particle size and enzyme loading, causes impaired catalyst efficiency expressed in a reduction of effectiveness factor and specific productivity. High penicillin G initial concentrations decrease the impact of internal diffusional restrictions by increasing the mass transfer towards porous catalyst until product inhibition becomes significant over approximately 50 mM of initial penicillin G, where a drop in conversion rate and a maximum in specific productivity are then obtained. Results highlight the relevance of considering internal diffusional restrictions, reactor performance, and productivity analysis for proper catalyst and reactor design.

  8. Immobilization and Characterization of Penicillin G Acylase (PGA) Immobilized on Magnetic Ni₀.₅Zn₀.₅Fe₂O₄ Nanoparticles.

    PubMed

    Liu, Ruijiang; Fan, Jiawen; Zhang, Yewang; Wang, Peng; Shen, Xiangqian

    2016-01-01

    Magnetic Ni₀.₅Zn₀.₅Fe₂O₄ nanoparticles were prepared via the solution combustion process and their microstructure and magnetic properties were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM). The as-prepared magnetic Ni₀.₅Zn₀.₅Fe₂O₄ nanoparticles are characterized with average grain size of about 20 nm and magnetization of 90.3 Am²/kg. The surface of magnetic Ni₀.₅Zn₀.₅Fe₂O₄ nanoparticles was modified by use of sodium silicate and N-(3-Dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride, and the penicillin G acylase (PGA) was successfully immobilized on the surface-modified magnetic Ni₀.₅Zn₀.₅Fe₂O₄ nanoparticles. The results show that the activity for the immobilized PGA is affected less by pH and temperature than that for the free PGA, and the immobilized PGA exhibits a high effective activity, good stability of enzyme catalyst. This immobilized PGA on magnetic Ni₀.₅Zn₀.₅Fe₂O₄ nanoparticles can be separated from the solution by the external magnetic field for cyclic utilization, and they could retain about 70% of initial enzyme activity after 11 consecutive operations. The kinetic parameters (Km and Vmax) were determined, and the value of Km for the immobilized PGA (204.53 mmol/L) is higher than that of the free enzyme (3.50 mmol/L), while Vmax (1.93 mmol/min) is also larger than that of the free enzyme (0.838 mmol/min). PMID:27398443

  9. A new biocatalyst: Penicillin G acylase immobilized in sol-gel micro-particles with magnetic properties.

    PubMed

    Bernardino, Susana M S A; Fernandes, Pedro; Fonseca, Luís P

    2009-05-01

    The present work focuses on the development and basic characterization of a new magnetic biocatalyst, namely penicillin G acylase (PGA), immobilized in sol-gel matrices with magnetic properties, ultimately aimed for application in cephalexin (CEX) synthesis. A mechanically stable carrier, based on porous xerogels silica matrixes starting from tetramethoxysilane (TMOS), was prepared leading to micro-carriers with medium sized particles of 30 microm, as determined by scanning electron microscopy. An immobilization yield of 95-100% and a recovered activity of 50-65% at 37 degrees C, as determined by penicillin G (PG) hydrolysis (pH STAT method), were observed. These results clearly exceed those reported in a previous work on PGA immobilization in sol-gel, where only 10% of activity was recovered. The values of activity were kept constant for 6 months. Immobilized PGA (682 U/g(dry weight)) retained high specific activity throughout ten consecutive runs for PG hydrolysis, suggesting adequate biocatalyst stability. The CEX synthesis was performed at 14 degrees C, using the free and immobilized PGA in aqueous medium. Phenylglycine methyl ester was used as acyl donor at 90 mM and 7-aminodeacetoxycephalosporanic acid was the limiting substrate at 30 mM. The CEX stoichiometric yield after 1-h reaction was close to 68% (23 mM CEX/h) and 65% (19 mM CEX/h), respectively. PMID:19418472

  10. A new biocatalyst: Penicillin G acylase immobilized in sol-gel micro-particles with magnetic properties.

    PubMed

    Bernardino, Susana M S A; Fernandes, Pedro; Fonseca, Luís P

    2009-05-01

    The present work focuses on the development and basic characterization of a new magnetic biocatalyst, namely penicillin G acylase (PGA), immobilized in sol-gel matrices with magnetic properties, ultimately aimed for application in cephalexin (CEX) synthesis. A mechanically stable carrier, based on porous xerogels silica matrixes starting from tetramethoxysilane (TMOS), was prepared leading to micro-carriers with medium sized particles of 30 microm, as determined by scanning electron microscopy. An immobilization yield of 95-100% and a recovered activity of 50-65% at 37 degrees C, as determined by penicillin G (PG) hydrolysis (pH STAT method), were observed. These results clearly exceed those reported in a previous work on PGA immobilization in sol-gel, where only 10% of activity was recovered. The values of activity were kept constant for 6 months. Immobilized PGA (682 U/g(dry weight)) retained high specific activity throughout ten consecutive runs for PG hydrolysis, suggesting adequate biocatalyst stability. The CEX synthesis was performed at 14 degrees C, using the free and immobilized PGA in aqueous medium. Phenylglycine methyl ester was used as acyl donor at 90 mM and 7-aminodeacetoxycephalosporanic acid was the limiting substrate at 30 mM. The CEX stoichiometric yield after 1-h reaction was close to 68% (23 mM CEX/h) and 65% (19 mM CEX/h), respectively.

  11. Immobilization of penicillin G acylase in epoxy-activated magnetic cellulose microspheres for improvement of biocatalytic stability and activities.

    PubMed

    Luo, Xiaogang; Zhang, Lina

    2010-11-01

    We prepared magnetic cellulose porous microspheres (MCM) with mean diameter of ∼200 μm by employing the sol-gel transition (SGT) method from a mixture of magnemite ferrofluid and cellulose dissolved in 7 wt % NaOH/12% urea aqueous solvent precooled to -12 °C. Subsequently, the cellulose microspheres were activated with epoxy chloropropane to enhance loading efficiency of biomacromolecules. Their morphology, structure, and properties were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray diffraction, and vibrating-sample magnetometer. The results indicated that the spherical magnetic γ-Fe2O3 nanoparticles with mean size of 10 nm were uniformly dispersed and embedded in the cellulose substrate of MCM, and the structure and nature of γ-Fe2O3 were conserved perfectly. Penicillin G acylase (PGA) as a biocatalyst was immobilized successfully in the porous microspheres, as a result of the existence of the cavity and affinity forces in the activated cellulose matrix. The immobilized PGA exhibited highly effective catalytic activity, thermal stability, and enhanced tolerance to pH variations. Furthermore, the cellulose microspheres loaded with the enzymes could be removed and recovered easily by introducing a magnetic field, leading to an acceptable reusability. Therefore, we have provided a simple and biocompatible support for the enzyme immobilization, which will be promising for the applications in the biomaterial fields. PMID:20919701

  12. [Screening of strain producing extracellular penicillin acylase].

    PubMed

    Wang, Z; Han, W; Men, D; Wang, Q

    1992-04-01

    Ninety-eight strains having extracellular penicillin acylase activity were derived from soil samples by colour-developing method. 10 strains of them possess higher activity of penicillin acylase. All of those are found to be Bacillus megaterium. The optimum condition of enzyme production was investigated with the strain No. 46 which is from No. 247 by single colony isolation. The productivity of penicillin acylase in the optimum condition have been enhanced 2.5 times more than that in the screening condition. The mutant strain, Bacillus megaterium UL-81, which penicillin acylase activity reached the level of 723u/100ml of broth was obtained from No. 46 by treatment with physical and chemical factors. The penicillin acylase activity of UL-81 can reach 820u/100 ml in 500L fermentor. The mutant strain differed from parent strain in the morphology of colony, the size of cells, the effect of concentration and the addition time of phenylacetic acid on the production of penicillin acylase. PMID:1598760

  13. In situ one-pot preparation of superparamagnetic hydrophilic porous microspheres for covalently immobilizing penicillin G acylase to synthesize amoxicillin

    NASA Astrophysics Data System (ADS)

    Xue, Ping; Gu, Yaohua; Su, Weiguang; Shuai, Huihui; Wang, Julan

    2016-01-01

    Magnetic hydrophilic porous microspheres were successfully one-pot synthesized for the first time via in situ inverse suspension polymerization of glycidyl methacrylate, N,N‧-methylene bisacrylamide and 2-hydroxyethyl methacrylate in the presence of Fe3+ and Fe2+ dispersed in formamide, which were denoted as magnetic Fe3O4-GMH microspheres. The morphology and properties of magnetic Fe3O4-GMH microspheres were characterized by SEM, VSM, XRD, FTIR, and so on. The formamide content had an important influence on the morphology of Fe3O4-GMH, and nearly perfectly spherical Fe3O4-GMH particles were formed when the amount of formamide was 15 ml. The diameters of the microspheres were in the range of 100-200 μm and Fe3O4-GMH exhibited superparamagnetic behavior with the saturation magnetization of 5.44 emu/g. The specific surface area of microspheres was 138.7 m2/g, the average pore diameter and pore volume were 15.1 nm and 0.60 cm3/g, respectively. The content of oxirane groups on Fe3O4-GMH was 0.40 mmol/g. After penicillin G acylase (PGA) was covalently immobilized on Fe3O4-GMH microspheres, the catalytic performance for amoxicillin synthesis by 6-aminopenicillanic acid and D-hydroxyphenylglycine methyl ester was largely improved. As a result, 90.1% amoxicillin yield and 1.18 of the synthesis/hydrolysis (S/H) ratio were achieved on PGA/Fe3O4-GMH with ethylene glycol as solvent, but only 62.6% amoxicillin yield and 0.37 of the S/H ratio were obtained on free PGA under the same reaction conditions. Furthermore, the amoxicillin yield and S/H ratio were still kept at 88.2% and 1.06, respectively after the immobilized PGA was magnetically separated and recycled for 10 times, indicating that PGA/Fe3O4-GMH had a very good reusability.

  14. Hydrophilic porous magnetic poly(GMA-MBAA-NVP) composite microspheres containing oxirane groups: An efficient carrier for immobilizing penicillin G acylase

    NASA Astrophysics Data System (ADS)

    Xue, Ping; Su, Weiguang; Gu, Yaohua; Liu, Haifeng; Wang, Julan

    2015-03-01

    Magnetic hydrophilic polymeric microspheres containing oxirane groups were prepared by inverse suspension polymerization of glycidyl methacrylate (GMA), N, N‧-methylene bisacrylamide (MBAA) and N-vinyl pyrrolidone (NVP) in the existence of formamide, which were denoted as magnetic poly(GMA-MBAA-NVP) microspheres. The magnetic poly(GMA-MBAA-NVP) microspheres were characterized by scanning electron microscopy (SEM), FT-IR spectroscopy, X-ray diffraction (XRD), vibrating sample magnetometer (VSM) and so on. The results showed that poly(GMA-MBAA-NVP) microspheres possessed well spherical shape, narrow size distribution, abundant porous structure, reactive oxirane groups and superparamagnetic properties. Formamide used in the present work served as a modifier, a dispersant and a porogen to form final porous polymer microspheres. The penicillin G acylase (PGA) was covalently immobilized onto the magnetic microspheres through the reaction between the amino groups of enzyme and the oxirane groups on the microspheres for producing 6-aminopenicillanic acid (6-APA). The effects of GMA/NVP ratio and crosslink density on the activity of immobilized PGA were investigated. The highest apparent activity, enzyme loading and coupling yield of immobilized PGA were 821 IU/g, 65.3 mg/g and 42.3% respectively when the mass ratio of GMA/NVP was 1:1 and crosslink density was 60%. Compared with the free PGA, immobilized PGA showed a wider range of pH value and reaction temperature. The relative activity and reaction rate of immobilized PGA remained almost constant after 20 recycles. The magnetic poly(GMA-MBAA-NVP) microspheres would be very promising carriers for immobilizing enzymes in industrial application.

  15. A new role for penicillin acylases: degradation of acyl homoserine lactone quorum sensing signals by Kluyvera citrophila penicillin G acylase.

    PubMed

    Mukherji, Ruchira; Varshney, Nishant Kumar; Panigrahi, Priyabrata; Suresh, C G; Prabhune, Asmita

    2014-03-01

    Use of penicillin acylases for the production of semi-synthetic penicillins is well-known. Escherichia coli penicillin G acylase (EcPGA) has been extensively used for this purpose; however, Kluyvera citrophila penicillin G acylase (KcPGA) is assumed to be a better substitute, owing to its increased resilience to extreme pH conditions and ease of immobilization. In the present article we report a new dimension for the amidase activity of KcPGA by demonstrating its ability to cleave bacterial quorum sensing signal molecules, acyl homoserine lactones (AHL) with acyl chain length of 6-8 with or without oxo-substitution at third carbon position. Initial evidence of AHL degrading capability of KcPGA was obtained using CV026 based bioassay method. Kinetic studies performed at pH 8.0 and 50 °C revealed 3-oxo-C6 HSL to be the best substrate for the enzyme with V(max) and K(m) values of 21.37+0.85 mM/h/mg of protein and 0.1+0.01 mM, respectively. C6 HSL was found to be the second best substrate with V(max) and K(m) value of 10.06+0.27 mM/h/mg of protein and 0.28+0.02 mM, respectively. Molecular modeling and docking studies performed on the active site of the enzyme support these findings by showing the fitting of AHLs perfectly within the hydrophobic pocket of the enzyme active site.

  16. Penicillin acylases revisited: importance beyond their industrial utility.

    PubMed

    Avinash, Vellore Sunder; Pundle, Archana Vishnu; Ramasamy, Sureshkumar; Suresh, Cheravakkattu Gopalan

    2016-01-01

    It is of great importance to study the physiological roles of enzymes in nature; however, in some cases, it is not easily apparent. Penicillin acylases are pharmaceutically important enzymes that cleave the acyl side chains of penicillins, thus paving the way for production of newer semi-synthetic antibiotics. They are classified according to the type of penicillin (G or V) that they preferentially hydrolyze. Penicillin acylases are also used in the resolution of racemic mixtures and peptide synthesis. However, it is rather unfortunate that the focus on the use of penicillin acylases for industrial applications has stolen the spotlight from the study of the importance of these enzymes in natural metabolism. The penicillin acylases, so far characterized from different organisms, show differences in their structural nature and substrate spectrum. These enzymes are also closely related to the bacterial signalling phenomenon, quorum sensing, as detailed in this review. This review details studies on biochemical and structural characteristics of recently discovered penicillin acylases. We also attempt to organize the available insights into the possible in vivo role of penicillin acylases and related enzymes and emphasize the need to refocus research efforts in this direction.

  17. Synthesis and characterization of pseudo-affinity ligand for penicillin acylase purification.

    PubMed

    Keçili, Rüstem; Say, Ridvan; Yavuz, Handan

    2006-11-15

    The aim of this work was to test a chromatographic affinity support containing methacryloyl antipyrine (MAAP) for penicillin acylase (PA) purification by using pure penicillin acylase and crude extract. First, MAAP as a pseudo-specific ligand was synthesized by using methacryloyl chloride and 4-aminoantipyrine. Polymer beads (average size diameter: 40-120 micro m) were prepared by suspension polymerization of ethylene glycol dimethacrylate (EGDMA) and MAAP. This approach for the preparation of adsorbent has several advantages over conventional preparation protocols. An expensive and time consuming step in the preparation of adsorbent is immobilization of a ligand to the adsorption matrix. In this procedure, affinity ligand MAAP acts as comonomer without further modification steps. Poly(EGDMA-MAAP) beads were characterized by FTIR, NMR and screen analysis. Elemental analysis of MAAP for nitrogen was estimated as 89.3 micro mol/g. The prepared adsorbent was then used for the capture of penicillin acylase in batch system. The maximum penicillin acylase adsorption capacity of the poly(EGDMA-MAAP) beads was found to be 82.2 mg/g at pH 5.0. Chromatography with crude feedstock resulted in 23.2-fold purification and 93% recovery with 1.0 M NaOH.

  18. Efficient cascade synthesis of ampicillin from penicillin G potassium salt using wild and mutant penicillin G acylase from Alcaligenes faecalis.

    PubMed

    Deng, Senwen; Ma, Xiaoqiang; Su, Erzheng; Wei, Dongzhi

    2016-02-10

    To avoid isolation and purification of the intermediate 6-aminopenicillanic acid (6-APA), a two-enzyme two-step cascade synthesis of ampicillin from penicillin G was established. In purely aqueous medium, penicillin G hydrolysis and ampicillin synthesis were catalyzed by immobilized wild-type and mutagenized penicillin G acylases from Alcaligenes faecalis (Af PGA), respectively (Fig. 1). The βF24 G mutant Af PGA (the 24th Phenylalanine of the β-subunit was replaced by Glycine) was employed for its superior performance in enzymatic synthesis of ampicillin. By optimizing the reaction conditions, including enzyme loading, temperature, initial pH and D-PGME/6-APA ratio, the conversion of the second step of ampicillin synthesis reached approximately 90% in 240 min and less than 1.7 mole D-PGME were required to produce 1 mole ampicillin. Overall, in a 285 min continuous two-step procedure, an ampicillin yield of 87% was achieved, demonstrating the possibility of improving the cascade synthesis of ampicillin by mutagenized PGA, providing an economically efficient and environmentally benign procedure for semi-synthetic penicillins antibiotics synthesis. PMID:26732414

  19. Cloning, purification, crystallization and preliminary structural studies of penicillin V acylase from Bacillus subtilis

    SciTech Connect

    Rathinaswamy, Priya; Pundle, Archana V.; Prabhune, Asmita A.; SivaRaman, Hepzibah; Brannigan, James A. Dodson, Guy G.; Suresh, C. G.

    2005-07-01

    An unannotated protein reported from B. subtilis has been expressed in E. coli and identified as possessing penicillin V acylase activity. The crystallization and preliminary crystallographic analysis of this penicillin V acylase is presented. Penicillin acylase proteins are amidohydrolase enzymes that cleave penicillins at the amide bond connecting the side chain to their β-lactam nucleus. An unannotated protein from Bacillus subtilis has been expressed in Escherichia coli, purified and confirmed to possess penicillin V acylase activity. The protein was crystallized using the hanging-drop vapour-diffusion method from a solution containing 4 M sodium formate in 100 mM Tris–HCl buffer pH 8.2. Diffraction data were collected under cryogenic conditions to a spacing of 2.5 Å. The crystals belonged to the orthorhombic space group C222{sub 1}, with unit-cell parameters a = 111.0, b = 308.0, c = 56.0 Å. The estimated Matthews coefficient was 3.23 Å{sup 3} Da{sup −1}, corresponding to 62% solvent content. The structure has been solved using molecular-replacement methods with B. sphaericus penicillin V acylase (PDB code 2pva) as the search model.

  20. Engineering the substrate specificity of a thermophilic penicillin acylase from thermus thermophilus.

    PubMed

    Torres, Leticia L; Cantero, Angel; del Valle, Mercedes; Marina, Anabel; López-Gallego, Fernando; Guisán, José M; Berenguer, José; Hidalgo, Aurelio

    2013-03-01

    A homologue of the Escherichia coli penicillin acylase is encoded in the genomes of several thermophiles, including in different Thermus thermophilus strains. Although the natural substrate of this enzyme is not known, this acylase shows a marked preference for penicillin K over penicillin G. Three-dimensional models were created in which the catalytic residues and the substrate binding pocket were identified. Through rational redesign, residues were replaced to mimic the aromatic binding site of the E. coli penicillin G acylase. A set of enzyme variants containing between one and four amino acid replacements was generated, with altered catalytic properties in the hydrolyses of penicillins K and G. The introduction of a single phenylalanine residue in position α188, α189, or β24 improved the K(m) for penicillin G between 9- and 12-fold, and the catalytic efficiency of these variants for penicillin G was improved up to 6.6-fold. Structural models, as well as docking analyses, can predict the positioning of penicillins G and K for catalysis and can demonstrate how binding in a productive pose is compromised when more than one bulky phenylalanine residue is introduced into the active site.

  1. Cloning, preparation and preliminary crystallographic studies of penicillin V acylase autoproteolytic processing mutants

    SciTech Connect

    Chandra, P. Manish; Brannigan, James A.; Prabhune, Asmita; Pundle, Archana; Turkenburg, Johan P.; Dodson, G. Guy; Suresh, C. G.

    2005-01-01

    The production, crystallization and characterization of three inactive mutants of penicillin V acylase from B. sphaericus in their respective precursor and processed forms are reported. The space groups are different for the native enzyme and the mutants. The crystallization of three catalytically inactive mutants of penicillin V acylase (PVA) from Bacillus sphaericus in precursor and processed forms is reported. The mutant proteins crystallize in different primitive monoclinic space groups that are distinct from the crystal forms for the native enzyme. Directed mutants and clone constructs were designed to study the post-translational autoproteolytic processing of PVA. The catalytically inactive mutants will provide three-dimensional structures of precursor PVA forms, plus open a route to the study of enzyme–substrate complexes for this industrially important enzyme.

  2. A process to produce penicillin G acylase by surface-adhesion fermentation using Mucor griseocyanus to obtain 6-aminopenicillanic acid by penicillin G hydrolysis.

    PubMed

    Martínez-Hernández, José Luis; Mata-Gómez, Marco Arnulfo; Aguilar-González, Cristóbal Noé; Ilyina, Anna

    2010-04-01

    The production of extracellular and mycelia-associated penicillin G acylase (maPGA) with Mucor griseocyanus H/55.1.1 by surface-adhesion fermentation using Opuntia imbricata, a cactus, as a natural immobilization support was studied. Enzyme activity to form 6-aminopencillanic acid (6-APA) from penicillin G was assayed spectrophotometrically. The penicillin G hydrolysis to 6-APA was evaluated at six different times using PGA samples recovered from the skim milk medium at five different incubation times. Additionally, the effect of varying the penicillin G substrate concentration level on the PGA enzyme activity was also studied. The maximum reaction rate, V (max), and the Michaelis constant, K (M), were determined using the Michaelis-Menten model. The maximum levels for maPGA and extracellular activity were found to be 2,126.50 international unit per liter (IU/l; equal to 997.83 IU/g of support) at 48 h and 755.33 IU/l at 60 h, respectively. Kinetics of biomass production for total biomass showed a maximum growth at 60 h of 3.36 and 2.55 g/l (equal to 0.012 g of biomass per gram of support) for the immobilized M. griseocyanus biomass. The maPGA was employed for the hydrolysis of penicillin G to obtain 6-APA in a batch reactor. The highest quantity of 6-APA obtained was 226.16 mg/l after 40-min reaction. The effect of substrate concentration on maPGA activity was evaluated at different concentrations of penicillin G (0-10 mM). K(M) and V(max) were determined to be 3.0 x 10(-3) M and 4.4 x 10(-3) mM/min, respectively.

  3. Stabilization of Penicillin G Acylase from Escherichia coli: Site-Directed Mutagenesis of the Protein Surface To Increase Multipoint Covalent Attachment

    PubMed Central

    Abian, Olga; Grazú, Valeria; Hermoso, Juan; González, Ramón; García, José Luis; Fernández-Lafuente, Roberto; Guisán, José Manuel

    2004-01-01

    Three mutations on the penicillin acylase surface (increasing the number of Lys in a defined area) were performed. They did not alter the enzyme's stability and kinetic properties; however, after immobilization on glyoxyl-agarose, the mutant enzyme showed improved stability under all tested conditions (e.g., pH 2.5 at 4°C, pH 5 at 60°C, pH 7 at 55°C, or 60% dimethylformamide), with stabilization factors ranging from 4 to 11 compared with the native enzyme immobilized on glyoxyl-agarose. PMID:14766616

  4. Penicillin V acylase from Pectobacterium atrosepticum exhibits high specific activity and unique kinetics.

    PubMed

    Avinash, V S; Ramasamy, Sureshkumar; Suresh, C G; Pundle, Archana

    2015-08-01

    Penicillin V acylases (PVAs, E.C.3.5.11) belong to the Ntn hydrolase super family of enzymes that catalyze the deacylation of the side chain from phenoxymethyl penicillin (penicillin V). Penicillin acylases find use in the pharmaceutical industry for the production of semi-synthetic antibiotics. PVAs employ the N-terminal cysteine residue as catalytic nucleophile and are structurally and evolutionarily related to bile salt hydrolases (BSHs). Here, we report the cloning and characterization of a PVA enzyme from the Gram-negative plant pathogen, Pectobacterium atrosepticum (PaPVA). The enzyme was cloned and expressed in Escherichia coli attaining a very high yield (250 mg/l) and a comparatively high specific activity (430 IU/mg). The enzyme showed marginally better pH and thermo-stability over PVAs characterized from Gram-positive bacteria. The enzyme also showed enhanced activity in presence of organic solvents and detergents. The enzyme kinetics turned out to be significantly different from that of previously reported PVAs, displaying positive cooperativity and substrate inhibition. The presence of bile salts had a modulating effect on PaPVA activity. Sequence analysis and characterization reveal the distinctive nature of these enzymes and underscore the need to study PVAs from Gram-negative bacteria. PMID:25931393

  5. Overexpression of Penicillin V Acylase from Streptomyces lavendulae and Elucidation of Its Catalytic Residues

    PubMed Central

    Torres-Bacete, Jesús; Hormigo, Daniel; Torres-Gúzman, Raquel; Arroyo, Miguel; Castillón, María Pilar; García, José Luis; Acebal, Carmen

    2014-01-01

    The pva gene from Streptomyces lavendulae ATCC 13664, encoding a novel penicillin V acylase (SlPVA), has been isolated and characterized. The gene encodes an inactive precursor protein containing a secretion signal peptide that is activated by two internal autoproteolytic cleavages that release a 25-amino-acid linker peptide and two large domains of 18.79 kDa (α-subunit) and 60.09 kDa (β-subunit). Based on sequence alignments and the three-dimensional model of SlPVA, the enzyme contains a hydrophobic pocket involved in catalytic activity, including Serβ1, Hisβ23, Valβ70, and Asnβ272, which were confirmed by site-directed mutagenesis studies. The heterologous expression of pva in S. lividans led to the production of an extracellularly homogeneous heterodimeric enzyme at a 5-fold higher concentration (959 IU/liter) than in the original host and in a considerably shorter time. According to the catalytic properties of SlPVA, the enzyme must be classified as a new member of the Ntn-hydrolase superfamily, which belongs to a novel subfamily of acylases that recognize substrates with long hydrophobic acyl chains and have biotechnological applications in semisynthetic antifungal production. PMID:25501472

  6. Production of penicillin acylase by a recombinant Escherichia coli using cheese whey as substrate and inducer.

    PubMed

    De León-Rodríguez, Antonio; Rivera-Pastrana, Dulce; Medina-Rivero, Emilio; Flores-Flores, José Luis; Estrada-Baltazar, Alejandro; Ordóñez-Acevedo, Leandro G; de la Rosa, Ana P Barba

    2006-12-01

    Cheese whey (CW) is the major subproduct from cheese manufacturing and it is considered as a waste pollutant since its high content of lactose. In this work a fermentation process for the production of penicillin acylase (PA) by a recombinant Escherichia coli and using CW as unique carbon source and inducer was developed. A design factorial 3(2) was used to evaluate the influence of independent variables (dissolved oxygen and CW concentration) on the ability of E. coli W3110/pPA102 to produce PA. Maximum specific PA activity of 781 U g(-1) was attained at 5 g L(-1) of CW and 3% dissolved oxygen. The results showed that CW can be used successfully as unique carbon source and inducer for the production of recombinant proteins using constructions driven by the lac promoter and this way reducing the discharges of that pollutant to the environment. PMID:17097344

  7. [The pH-dependent catalytic reaction of penicillin G acylase and its mutants].

    PubMed

    Chen, Jian-Bo; Yang, Sheng; Wu, Xing-Jia; Li, Shi-Yun; Yuan, Zhong-Yi

    2002-11-01

    The pH-dependence in the catalytic reaction of recombinant penicillin G acylase and its mutants from B.megaterium has been studied by using kinetic methods. pK(1) and pK(2)of the residues of the wild type penicillin G a cylase, involved in the catalyzed reaction, were 5.50-5.87 and 10.73, respectively, from the curves of logV(m) and log(V(m)/K(m)) versus pH. Results showed tha t the pK(1) and pK(2) values of these residues of the mutants were similar to that of the wild type. pK(1) of 5.64-5.86 for mutant A and 5.69-6.96 for mutant B were obtained, while pK(2) was 10.61 and 10.48 for mutant A and B, respectively. At the same time, pK values at different temperatures were investigated. The ionization enthalpies(deltaH) were 44.38-59.03 kJ/mol and 147.37 kJ/mol, respectively, from th e curve of pK versus temperature. It was presumed according to the results mentioned above that the ionizing residues, involved in the reaction, wer e histidine and lysine that are localized around the active site.

  8. Purification and preliminary crystallographic studies of penicillin G acylase from Providencia rettgeri.

    PubMed Central

    Klei, H. E.; Daumy, G. O.; Kelly, J. A.

    1995-01-01

    Two isoforms of the heterodimeric enzyme penicillin G acylase (EC 3.5.1.11) from Providencia rettgeri ATCC 31052 (strain Bro1) were purified to near homogeneity. The isoforms exhibited comparable enzymatic activities but differed slightly in the molecular weight and pI of their respective alpha-subunit. The origin of this difference was traced to the partial conversion of the N-terminal Gln of the alpha-subunit to pyrrolidonecarboxylic acid (pyro-Glu). The boundaries of the mature enzyme within the translated DNA sequence of the wild-type propeptide (GenBank M86533) were determined. The results conclusively identified the length of the signal peptide and the position of the spacer cleaved from the propeptide to form the active heterodimer. The molecular weights of the alpha- and beta-subunits, based on these termini, were 23.7 and 62.2 kDa, respectively. Both isoforms were crystallized independently as hexagonal bipyramids up to 0.60 mm in diameter in either space group P6(1)22 or P6(5)22 (a = b = 140.5 A and c = 209.5 A) from ammonium sulfate solutions buffered by 50 mM potassium phosphate at pH 7.5. The presence of glycerol, although not required, facilitated crystal growth. Native and heavy atom derivative data were collected to 3.0 A resolution, and the calculation of isomorphous replacement phases is under way. PMID:7795527

  9. Enzyme reaction engineering: synthesis of antibiotics catalysed by stabilized penicillin G acylase in the presence of organic cosolvents.

    PubMed

    Fernandez-Lafuente, R; Rosell, C M; Guisán, J M

    1991-11-01

    By using very active and very stable penicillin G acylase (PGA)--agarose derivatives we have studied the industrial design of equilibrium-controlled synthesis of lactamic antibiotics. In the presence of high concentrations of organic cosolvents we have carried out the direct enzymatic condensation of phenylacetic acid and 6-aminopenicillanic acid to yield the model antibiotic penicillin G. We have mainly studied the integrated effect of different variables that define the reaction medium on a number of parameters of industrial interest:time course of antibiotic synthesis, highest synthetic yields, stability of the catalyst, and solubility and stability of substrates and products. The main variables tested were the nature and concentration of the organic cosolvent, pH, and temperature. The effects of the variables tested on different parameters were quite different and sometimes opposite. Hence, the optimal experimental conditions for antibiotic synthesis catalysed by PGA were established, as a compromise solution, in order to obtain good values for every parameter of industrial interest. These conditions seem to be important parameters for scale-up (e.g. we have been able to reach more than 95% of synthetic yields with productivities around 0.5 tons of model antibiotic per year per liter of catalyst).

  10. Pseudomonas aeruginosa biofilm growth inhibition on medical plastic materials by immobilized esterases and acylase.

    PubMed

    Kisch, Johannes Martin; Utpatel, Christian; Hilterhaus, Lutz; Streit, Wolfgang R; Liese, Andreas

    2014-09-01

    Biofilms are matrix-encapsulated cell aggregates that cause problems in technical and health-related areas; for example, 65 % of all human infections are biofilm associated. This is mainly due to their ameliorated resistance against antimicrobials and immune systems. Pseudomonas aeruginosa, a biofilm-forming organism, is commonly responsible for nosocomial infections. Biofilm development is partly mediated by signal molecules, such as acyl-homoserine lactones (AHLs) in Gram-negative bacteria. We applied horse liver esterase, porcine kidney acylase, and porcine liver esterase; these can hydrolyze AHLs, thereby inhibiting biofilm formation. As biofilm infections are often related to foreign material introduced into the human body, we immobilized the enzymes on medical plastic materials. Biofilm formation was quantified by Crystal Violet staining and confocal laser scanning microscopy, revealing up to 97 % (on silicone), 54 % (on polyvinyl chloride), and 77 % (on polyurethane) reduced biomass after 68 h growth.

  11. Strategies for enhancing the production of penicillin G acylase from Bacillus badius: influence of phenyl acetic acid dosage.

    PubMed

    Rajendran, Karthikeyan; Mahadevan, Surianarayanan; Jeyaprakash, Rajendhran; Paramasamy, Gunasekaran; Mandal, Asit Baran

    2013-11-01

    Bacillus badius isolated from soil has been identified as potential producer of penicillin G acylase (PGA). In the present study, batch experiments performed at optimized inoculum size, temperature, pH, and agitation yielded a maximum PGA of 9.5 U/ml in shake flask. The experiments conducted in bioreactor with different oxygen flow rates revealed that 0.66 vvm oxygen flow rate could be sufficient for the maximum PGA activity of 12.7 U/ml. From a detailed investigation on the strategies of the addition of phenyl acetic acid (PAA) for increasing the production of PGA, it was found that the controlled addition of 10 ml of 0.1 % (w/v) PAA once in every 2 h from 6th hour of growth showed the maximum PGA activity of 32 U/ml. Thus, our studies for the first time showed that at concentration above 0.1 % (w/v) PAA, the PGA production decreased. This selective condition paves the way for less costly bioprocess for the production of PGA. PMID:23949729

  12. Enantioselective acylation of β-phenylalanine acid and its derivatives catalyzed by penicillin G acylase from Alcaligenes faecalis.

    PubMed

    Li, Dengchao; Ji, Lilian; Wang, Xinfeng; Wei, Dongzhi

    2013-01-01

    This study developed a simple, efficient method for producing racemic β-phenylalanine acid (BPA) and its derivatives via the enantioselective acylation catalyzed by the penicillin G acylase from Alcaligenes faecalis (Af-PGA). When the reaction was run at 25°C and pH 10 in an aqueous medium containing phenylacetamide and BPA in a molar ratio of 2:1, 8 U/mL enzyme and 0.1 M BPA, the maximum BPA conversion efficiency at 40 min only reached 36.1%, which, however, increased to 42.9% as the pH value and the molar ratio of phenylacetamide to BPA were elevated to 11 and 3:1, respectively. Under the relatively optimum reaction conditions, the maximum conversion efficiencies of BPA derivatives all reached about 50% in a relatively short reaction time (45-90 min). The enantiomeric excess value of product (ee(p)) and enantiomeric excess value of substrate (ee(s)) were all above 98% and 95%, respectively. These results suggest that the method established in this study is practical, effective, and environmentally benign and may be applied to industrial production of enantiomerically pure BPA and its derivatives. PMID:23302108

  13. Computational Design of a pH Stable Enzyme: Understanding Molecular Mechanism of Penicillin Acylase's Adaptation to Alkaline Conditions

    PubMed Central

    Suplatov, Dmitry; Panin, Nikolay; Kirilin, Evgeny; Shcherbakova, Tatyana; Kudryavtsev, Pavel; Švedas, Vytas

    2014-01-01

    Protein stability provides advantageous development of novel properties and can be crucial in affording tolerance to mutations that introduce functionally preferential phenotypes. Consequently, understanding the determining factors for protein stability is important for the study of structure-function relationship and design of novel protein functions. Thermal stability has been extensively studied in connection with practical application of biocatalysts. However, little work has been done to explore the mechanism of pH-dependent inactivation. In this study, bioinformatic analysis of the Ntn-hydrolase superfamily was performed to identify functionally important subfamily-specific positions in protein structures. Furthermore, the involvement of these positions in pH-induced inactivation was studied. The conformational mobility of penicillin acylase in Escherichia coli was analyzed through molecular modeling in neutral and alkaline conditions. Two functionally important subfamily-specific residues, Gluβ482 and Aspβ484, were found. Ionization of these residues at alkaline pH promoted the collapse of a buried network of stabilizing interactions that consequently disrupted the functional protein conformation. The subfamily-specific position Aspβ484 was selected as a hotspot for mutation to engineer enzyme variant tolerant to alkaline medium. The corresponding Dβ484N mutant was produced and showed 9-fold increase in stability at alkaline conditions. Bioinformatic analysis of subfamily-specific positions can be further explored to study mechanisms of protein inactivation and to design more stable variants for the engineering of homologous Ntn-hydrolases with improved catalytic properties. PMID:24959852

  14. Beta-lactamase-free penicillin amidase from Alcaligenes sp.: isolation strategy, strain characteristics, and enzyme immobilization.

    PubMed

    Pal, A; Samanta, T B

    1999-11-01

    Isolation and characterization of a beta-lactamase (EC 3.5.2.6)-free, penicillin amidase (penicillin amidohydrolase, EC 3.5.1. 11)-producing organism is reported. The test strain was isolated by an enrichment technique with a substrate other than penicillins. The isolated strain belongs to the genus Alcaligenes. Phenylacetic acid was found to be the inducer of penicillin amidase. The amidase has a broad substrate spectrum. It is very active against penicillin G and semisynthetic cephalosporins, whereas penicillin V and semisynthetic penicillins acted moderately as a substrate. Immobilized cells of Alcaligenes sp. were shown to act as a reversible enzyme. PMID:10489431

  15. Polymer immobilized enzyme optrodes for the detection of penicillin

    SciTech Connect

    Kulp, T.J.; Camins, I.; Angel, S.M.; Munkholm, C.; Walt, D.R.

    1987-12-15

    The preparation and performance of two enzyme-based fiber-optic sensors (optrodes) capable of detecting penicillin are described. Each sensor consists of a polymer membrane that is covalently attached to the tip of a glass optical fiber. The membrane contains the enzyme penicillinase and a pH-sensitive fluorescent dye. A signal is produced when the enzyme catalyzes the cleavage of the ..beta..-lactam ring of penicillin to produce penicilloic acid and, consequently, a pH change in the microenvironment of the membrane. The sensors differ in the way the polymer membrane is constructed and in the type of pH indicator dye used. Both optrodes exhibit response times (40-60 s) significantly lower than those of the corresponding enzyme electrodes (2 min). Each gives a linear response over the concentration range of 0.00025 to 0.01 M penicillin G, when measured in a 0.005 M phosphate buffer. The data indicate that these immobilization strategies produce similar results and may be considered complementary alternatives in future enzyme optrode applications.

  16. Immobilization and stabilization of cephalosporin C acylase on aminated support by crosslinking with glutaraldehyde and further modifying with aminated macromolecules.

    PubMed

    He, Hua; Wei, Yanmei; Luo, Hui; Li, Xi; Wang, Xiaona; Liang, Chen; Chang, Yanhong; Yu, Huimin; Shen, Zhongyao

    2015-01-01

    In this work, cephalosporin C acylase (CA), a heterodimeric enzyme of industrial potential in direct hydrolysis of cephalosporin C (CPC) to 7-aminocephalosporanic acid (7-ACA), was covalently immobilized on the aminated support LX1000-HA (HA) with two different protocols. The stability of CA adsorbed onto the HA support followed by crosslinking with glutaraldehyde (HA-CA-glut) was better than that of the CA covalently immobilized on the glutaraldehyde preactivated HA support (HA-glut-CA). The thermostabilization factors (compared with the free enzyme) of these two immobilized enzymes were 11.2-fold and 2.2-fold, respectively. In order to improve the stability of HA-CA-glut, a novel strategy based on postimmobilization modifying with aminated molecules was developed to take advantage of the glutaraldehyde moieties left on the enzyme and support. The macromolecules, such as polyethyleneimine (PEI) and chitosan, had larger effects than small molecules on the thermal stability of the immobilized enzyme perhaps due to crosslinking of the enzymes and support with each other. The quaternary structure of the CA could be much stabilized by this novel approach including physical adsorption on aminated support, glutaraldehyde treatment, and macromolecule modification. The HA-CA-glut-PEI20000 (the HA-CA-glut postmodified with PEI Mw = 20,000) had a thermostabilization factor of 20-fold, and its substrate affinity (Km = 14.3 mM) was better than that of HA-CA-glut (Km = 33.4 mM). The half-life of the immobilized enzymes HA-CA-glut-PEI20000 under the CPC-catalyzing conditions could reach 28 cycles, a higher value than that of HA-CA-glut (21 cycles).

  17. Determination of Penicillin Using an Immobilized Enzyme Electrode: An Undergraduate Experiment.

    ERIC Educational Resources Information Center

    Mifflin, Theodore E.; And Others

    1984-01-01

    Background information, procedures, and results are provided for an experiment in which students: (1) construct an immobilized penicillinase electrode; (2) evaluate electron response as a function of penicillin concentration; and (3) study effects of solvent compositions, ionic strength, and equilibrium time upon electrode response. (JN)

  18. A breakthrough in enzyme technology to fight penicillin resistance-industrial application of penicillin amidase.

    PubMed

    Buchholz, Klaus

    2016-05-01

    Enzymatic penicillin hydrolysis by penicillin amidase (also penicillin acylase, PA) represents a Landmark: the first industrially and economically highly important process using an immobilized biocatalyst. Resistance of infective bacteria to antibiotics had become a major topic of research and industrial activities. Solutions to this problem, the antibiotics resistance of infective microorganisms, required the search for new antibiotics, but also the development of derivatives, notably penicillin derivatives, that overcame resistance. An obvious route was to hydrolyse penicillin to 6-aminopenicillanic acid (6-APA), as a first step, for the introduction via chemical synthesis of various different side chains. Hydrolysis via chemical reaction sequences was tedious requiring large amounts of toxic chemicals, and they were cost intensive. Enzymatic hydrolysis using penicillin amidase represented a much more elegant route. The basis for such a solution was the development of techniques for enzyme immobilization, a highly difficult task with respect to industrial application. Two pioneer groups started to develop solutions to this problem in the late 1960s and 1970s: that of Günter Schmidt-Kastner at Bayer AG (Germany) and that of Malcolm Lilly of Imperial College London. Here, one example of this development, that at Bayer, will be presented in more detail since it illustrates well the achievement of a solution to the problems of industrial application of enzymatic processes, notably development of an immobilization method for penicillin amidase suitable for scale up to application in industrial reactors under economic conditions. A range of bottlenecks and technical problems of large-scale application had to be overcome. Data giving an inside view of this pioneer achievement in the early phase of the new field of biocatalysis are presented. The development finally resulted in a highly innovative and commercially important enzymatic process to produce 6-APA that

  19. Mathematical model for internal pH control in immobilized enzyme particles

    SciTech Connect

    Liou, J.K.; Rousseau, I.

    1986-10-01

    A mathematical model has been developed for the internal pH control in immobilized enzyme particles. This model describes the kinetics of a coupled system of two enzymes, immobilized in particles of either planar, cylindrical, or spherical shape. The enzyme kinetics are assumed to be of a mixed type, including Michaelis-Menten kinetics, uncompetitive substrate inhibition, and competitive and noncompetitive product inhibition. In a case study we have considered the enzyme combination urease and penicillin acylase, whose kinetics are coupled through the pH dependence of the kinetic parameters. The hydrolysis of urea by urease yields ammonia and carbon dioxide, whereas benzylpenicillin (Pen-G) is converted to 6-animo penicillanic acid and phenyl acetic acid by penicillin acylase. The production of acids by the latter enzyme will cause a decrease in pH. Because of the presence of the ammonia-carbon dioxide system, however, the pH may be kept under control. In order to obtain information about the optimum performance of this enzymatic pH controller, we have computed the effectiveness factor and the conversion in a CSTR at different enzyme loadings. The results of the computer simulations indicate that a high conversion of Pen-G may be achieved (80-90%) at bulk pH values of about 7.5 - 8. 27 references.

  20. Isolation and characterization of a new strain of Achromobacter sp. with beta-lactam antibiotic acylase activity.

    PubMed

    Plhácková, K; Becka, S; Skrob, F; Kyslík, P

    2003-10-01

    A bacterial strain producing a beta-lactam antibiotic acylase, able to hydrolyze ampicillin to 6-aminopenicillanic acid more efficiently than penicillin G, was isolated from soil and characterized. The isolate was identified as Achromobacter sp. using the phenotypic characteristics, composition of cellular fatty acids and 16S rRNA gene sequence. The enzyme synthesis was fully induced by phenylacetic acid (PAA) at a concentration of 2 g l(-1). PAA at concentrations up to 12 g l(-1) had no negative effect on the specific activity of acylase and biomass production, but slowed down the specific growth rate. Benzoic or 4-hydroxyphenylacetic acids can also induce synthesis of the enzyme. The inducers were metabolized in all cases. Acylase activity in cell-free extracts was determined with various substrates; ampicillin, cephalexin and amoxicillin were hydrolyzed 1.5- and 2-times faster than penicillin G. A high stability of acylase activity was observed over a wide range of pH (5.0-8.5) and at temperatures above 55 degrees C. PMID:12827318

  1. Hydrogel coated monoliths for enzymatic hydrolysis of penicillin G.

    PubMed

    de Lathouder, K M; Smeltink, M W; Straathof, A J J; Paasman, M A; van de Sandt, E J A X; Kapteijn, F; Moulijn, J A

    2008-08-01

    The objective of this work was to develop a hydrogel-coated monolith for the entrapment of penicillin G acylase (E. coli, PGA). After screening of different hydrogels, chitosan was chosen as the carrier material for the preparation of monolithic biocatalysts. This protocol leads to active immobilized biocatalysts for the enzymatic hydrolysis of penicillin G (PenG). The monolithic biocatalyst was tested in a monolith loop reactor (MLR) and compared with conventional reactor systems using free PGA, and a commercially available immobilized PGA. The optimal immobilization protocol was found to be 5 g l(-1) PGA, 1% chitosan, 1.1% glutaraldehyde and pH 7. Final PGA loading on glass plates was 29 mg ml(-1) gel. For 400 cpsi monoliths, the final PGA loading on functionalized monoliths was 36 mg ml(-1) gel. The observed volumetric reaction rate in the MLR was 0.79 mol s(-1) m(-3) (monolith). Apart from an initial drop in activity due to wash out of PGA at higher ionic strength, no decrease in activity was observed after five subsequent activity test runs. The storage stability of the biocatalysts is at least a month without loss of activity. Although the monolithic biocatalyst as used in the MLR is still outperformed by the current industrial catalyst (immobilized preparation of PGA, 4.5 mol s(-1) m(-3) (catalyst)), the rate per gel volume is slightly higher for monolithic catalysts. Good activity and improved mechanical strength make the monolithic bioreactor an interesting alternative that deserves further investigation for this application. Although moderate internal diffusion limitations have been observed inside the gel beads and in the gel layer on the monolith channel, this is not the main reason for the large differences in reactor performance that were observed. The pH drop over the reactor as a result of the chosen method for pH control results in a decreased performance of both the MLR and the packed bed reactor compared to the batch system. A different reactor

  2. Hitler's penicillin.

    PubMed

    Wainwright, Milton

    2004-01-01

    During the Second World War, the Germans and their Axis partners could only produce relatively small amounts of penicillin, certainly never enough to meet their military needs; as a result, they had to rely upon the far less effective sulfonamides. One physician who put penicillin to effective use was Hitler's doctor, Theodore Morell. Morell treated the Führer with penicillin on a number of occasions, most notably following the failed assassination attempt in July 1944. Some of this penicillin appears to have been captured from, or inadvertently supplied by, the Allies, raising the intriguing possibility that Allied penicillin saved Hitler's life. PMID:15259203

  3. Hitler's penicillin.

    PubMed

    Wainwright, Milton

    2004-01-01

    During the Second World War, the Germans and their Axis partners could only produce relatively small amounts of penicillin, certainly never enough to meet their military needs; as a result, they had to rely upon the far less effective sulfonamides. One physician who put penicillin to effective use was Hitler's doctor, Theodore Morell. Morell treated the Führer with penicillin on a number of occasions, most notably following the failed assassination attempt in July 1944. Some of this penicillin appears to have been captured from, or inadvertently supplied by, the Allies, raising the intriguing possibility that Allied penicillin saved Hitler's life.

  4. Characterization and study of the orientation of immobilized enzymes by tryptic digestion and HPLC-MS: design of an efficient catalyst for the synthesis of cephalosporins.

    PubMed

    Temporini, Caterina; Bonomi, Paolo; Serra, Immacolata; Tagliani, Auro; Bavaro, Teodora; Ubiali, Daniela; Massolini, Gabriella; Terreni, Marco

    2010-06-14

    An innovative approach to determine the orientation of penicillin G acylase (PGA) from Escherichia coli covalently immobilized onto solid supports has been developed. This method is based on tryptic digestion of immobilized PGA followed by HPLC-MS analysis of the released peptides which are supposed to be only those exposed toward the reaction medium and not directly bound to the solid support. To this purpose, PGA was immobilized on Eupergit C (acrylic hydrophobic resin) and glyoxyl-agarose (hydrophilic resin) functionalized with epoxy and aldehyde groups, respectively, both involving the Lys residues of the protein. The peptide maps obtained were analyzed to derive the orientation of immobilized PGA, as the position of the detected Lys gave indication concerning the accessibility of the different areas of the protein. The results indicate that PGA immobilization on both supports involves mainly Lys located near the binding pocket (70%). Some differences in the enzyme orientation on the two supports can be deduced by the presence of different unbound Lys residues in the released peptides, specific to each support (Lys 117alpha for PGA-Eupergit C; Lys 163alpha and Lys 165alpha for PGA-glyoxyl-agarose). These results have been correlated with the data obtained in the kinetically controlled synthesis and indicate that the orientation of PGA on both supports is partially unfavorable, driving the active site near the support surface. This type of orientation of the enzyme enhances the effect of the nature of the support and of the binding chemistry on the catalytic properties. The information obtained indicated the most suitable support and activation strategy to design an immobilized acylase with good synthetic properties for preparative processes. The glyoxyl-Eupergit C support with enhanced porosity synergically combines the mechanical stability and synthetic performances of immobilized PGA and was successfully used in the synthesis of several cephalosporins.

  5. Improved specific productivity in cephalexin synthesis by immobilized PGA in silica magnetic micro-particles.

    PubMed

    Bernardino, Susana M S A; Fernandes, Pedro; Fonseca, Luís P

    2010-12-01

    There is a marked trend in pharmaceutical industry towards the replacement of classical organic methods by "green" alternatives that minimize or eliminate the generation of waste and avoid, where possible, the use of toxic and/or hazardous reagents and solvents. In this work the kinetically controlled synthesis of cephalexin by soluble and penicillin G acylase immobilized in sol-gel micro-particles with magnetic properties was performed in aqueous media with PGME and 7-ADCA as substrates, at different concentrations of substrate, temperature, pH, enzyme to substrate ratio and acyl donor to nucleophile ratio. Excess acyl donor had a strong effect on cephalexin productivity. A PGME/7-ADCA ratio of 3 was considered optimum. A maximum specific productivity of 5.9 mmol h(-1), gbiocatalyst(-1) at 160 mM 7-ADCA, 480 mM PGME and low enzyme to substrate ratio at 32.5 U mmol(-1) 7-ADCA was obtained with immobilized PGA in full aqueous medium, suggesting that diffusional limitations were minimized when compared with other commercial biocatalysts. A half-life of 133 h for the immobilized biocatalyst was estimated during cephalexin synthesis in the presence of 100 mM 7-ADCA and 300 mM PGME, in 50 mM Tris/HCl at pH 7.2 and 14°C. These results compare quite favorably with those previously reported for the kinetically controlled synthesis of cephalexin. PMID:20632377

  6. Improved specific productivity in cephalexin synthesis by immobilized PGA in silica magnetic micro-particles.

    PubMed

    Bernardino, Susana M S A; Fernandes, Pedro; Fonseca, Luís P

    2010-12-01

    There is a marked trend in pharmaceutical industry towards the replacement of classical organic methods by "green" alternatives that minimize or eliminate the generation of waste and avoid, where possible, the use of toxic and/or hazardous reagents and solvents. In this work the kinetically controlled synthesis of cephalexin by soluble and penicillin G acylase immobilized in sol-gel micro-particles with magnetic properties was performed in aqueous media with PGME and 7-ADCA as substrates, at different concentrations of substrate, temperature, pH, enzyme to substrate ratio and acyl donor to nucleophile ratio. Excess acyl donor had a strong effect on cephalexin productivity. A PGME/7-ADCA ratio of 3 was considered optimum. A maximum specific productivity of 5.9 mmol h(-1), gbiocatalyst(-1) at 160 mM 7-ADCA, 480 mM PGME and low enzyme to substrate ratio at 32.5 U mmol(-1) 7-ADCA was obtained with immobilized PGA in full aqueous medium, suggesting that diffusional limitations were minimized when compared with other commercial biocatalysts. A half-life of 133 h for the immobilized biocatalyst was estimated during cephalexin synthesis in the presence of 100 mM 7-ADCA and 300 mM PGME, in 50 mM Tris/HCl at pH 7.2 and 14°C. These results compare quite favorably with those previously reported for the kinetically controlled synthesis of cephalexin.

  7. Effective antifouling using quorum-quenching acylase stabilized in magnetically-separable mesoporous silica.

    PubMed

    Lee, Byoungsoo; Yeon, Kyung-Min; Shim, Jongmin; Kim, Sang-Ryoung; Lee, Chung-Hak; Lee, Jinwoo; Kim, Jungbae

    2014-04-14

    Highly effective antifouling was achieved by immobilizing and stabilizing an acylase, disrupting bacterial cell-to-cell communication, in the form of cross-linked enzymes in magnetically separable mesoporous silica. This so-called "quorum-quenching" acylase (AC) was adsorbed into spherical mesoporous silica (S-MPS) with magnetic nanoparticles (Mag-S-MPS), and further cross-linked for the preparation of nanoscale enzyme reactors of AC in Mag-S-MPS (NER-AC/Mag-S-MPS). NER-AC effectively stabilized the AC activity under rigorous shaking at 200 rpm for 1 month, while free and adsorbed AC lost more than 90% of their initial activities in the same condition within 1 and 10 days, respectively. When applied to the membrane filtration for advanced water treatment, NER-AC efficiently alleviated the biofilm maturation of Pseudomonas aeruginosa PAO1 on the membrane surface, thereby enhancing the filtration performance by preventing membrane fouling. Highly stable and magnetically separable NER-AC, as an effective and sustainable antifouling material, has a great potential to be used in the membrane filtration for water reclamation.

  8. Penicillin G Benzathine Injection

    MedlinePlus

    ... to treat and prevent certain infections caused by bacteria. Penicillin G benzathine injection is in a class of antibiotics called penicillins. It works by killing bacteria that cause infections.Antibiotics such as penicillin G ...

  9. Identification of extracellular N-acylhomoserine lactone acylase from a Streptomyces sp. and its application to quorum quenching.

    PubMed

    Park, Sun-Yang; Kang, Hye-Ok; Jang, Hak-Sun; Lee, Jung-Kee; Koo, Bon-Tag; Yum, Do-Young

    2005-05-01

    N-acylhomoserine lactones (AHLs) play an important role in regulating virulence factors in pathogenic bacteria. Recently, the enzymatic inactivation of AHLs, which can be used as antibacterial targets, has been identified in several soil bacteria. In this study, strain M664, identified as a Streptomyces sp., was found to secrete an AHL-degrading enzyme into a culture medium. The ahlM gene for AHL degradation from Streptomyces sp. strain M664 was cloned, expressed heterologously in Streptomyces lividans, and purified. The enzyme was found to be a heterodimeric protein with subunits of approximately 60 kDa and 23 kDa. A comparison of AhlM with known AHL-acylases, Ralstonia strain XJ12B AiiD and Pseudomonas aeruginosa PAO1 PvdQ, revealed 35% and 32% identities in the deduced amino acid sequences, respectively. However, AhlM was most similar to the cyclic lipopeptide acylase from Streptomyces sp. strain FERM BP-5809, exhibiting 93% identity. A mass spectrometry analysis demonstrated that AhlM hydrolyzed the amide bond of AHL, releasing homoserine lactone. AhlM exhibited a higher deacylation activity toward AHLs with long acyl chains rather than short acyl chains. Interestingly, AhlM was also found to be capable of degrading penicillin G by deacylation, showing that AhlM has a broad substrate specificity. The addition of AhlM to the growth medium reduced the accumulation of AHLs and decreased the production of virulence factors, including elastase, total protease, and LasA, in P. aeruginosa. Accordingly, these results suggest that AHL-acylase, AhlM could be effectively applied to the control of AHL-mediated pathogenicity. PMID:15870355

  10. Penicillin G Benzathine and Penicillin G Procaine Injection

    MedlinePlus

    ... to treat and prevent certain infections caused by bacteria. Penicillin G benzathine and penicillin G procaine injection ... of medications called penicillins. It works by killing bacteria that cause infections.Antibiotics such as penicillin G ...

  11. Improved fiber-optic chemical sensor for penicillin

    SciTech Connect

    Healy, B.G.; Walt, D.R.

    1995-12-15

    An optical penicillin biosensor is described, based on the enzyme penicillinase. The sensor is fabricated by selective photodeposition of analyte-sensitive polymer matrices on optical imaging fibers. The penicillin-sensitive matrices are fabricated by immobilizing the enzyme as micrometer-sized particles in a polymer hydrogel with a covalently bound pH indicator. An array of penicillin-sensitive and pH-sensitive matrices are fabricated on the same fiber. This array allows for the simultaneous, independent measurement of pH and penicillin. Independent measurement of the two analytes allows penicillin to be quantitated in the presence of a concurrent pH change. An analysis was conducted of enzyme kinetic parameters in order to model the penicillin response of the sensor at all pH values. This analysis accounts for the varying activity of the immobilized penicillinase at different pH values. The sensor detects penicillin in the range 0.25-10.0 mM in the pH range 6.2-7.5. The sensor was used to quantify penicillin concentration produced during a Penicillium chrysogenum fermentation. 27 refs., 7 figs., 1 tab.

  12. Penicillin G Procaine Injection

    MedlinePlus

    Duracillin A-S ® ... Pfizerpen A-S® ... injection should not be used to treat gonorrhea (a sexually transmitted disease) or early in the treatment ... serious infections. Penicillin G procaine injection is in a class of medications called penicillins. It works by ...

  13. Penicillin V Potassium Oral

    MedlinePlus

    Penicillin V potassium is an antibiotic used to treat certain infections caused by bacteria such as pneumonia, scarlet fever, and ear, ... Penicillin V potassium comes as a tablet and liquid to take by mouth. It is usually taken every 6 hours (four ...

  14. Untoward penicillin reactions

    PubMed Central

    Guthe, T.; Idsöe, O.; Willcox, R. R.

    1958-01-01

    The literature on untoward reactions following the administration of penicillin is reviewed. These reactions, including a certain number of deaths which have been reported, are of particular interest to health administrations and to WHO in view of the large-scale programmes for controlling the treponematoses which are now under way—programmes affecting millions of people in many parts of the world. The most serious problems are anaphylactic sensitivity phenomena and superinfection or cross-infection with penicillin-resistant organisms, and the reactions involved range in intensity from the mildest to the fatal; the incidence of the latter is estimated at 0.1-0.3 per million injections. The authors point out that with increasing use of penicillin, more persons are likely to become sensitized and the number of reactions can therefore be expected to rise. The best prevention against such an increase is the restriction of the unnecessary use of penicillin. PMID:13596877

  15. Enzymatic hydrolysis of penicillin in mixed ionic liquids/water two-phase system.

    PubMed

    Jiang, Yangyang; Xia, Hansong; Guo, Chen; Mahmood, Iram; Liu, Huizhou

    2007-01-01

    In this paper, an integrated process involving the mixed ionic liquids/water two-phase system (MILWS) is proposed to improve the efficiency for enzymatic hydrolysis of penicillin G. First, hydrophilic [C4mim]BF4 (1-butyl-3-methylimidazolium tetrafluoraborate) and NaH2PO4 salt form an ionic liquids aqueous two-phase system (ILATPS), which could extract penicillin from its fermentation broth efficiently. Second, a hydrophobic [C4mim]PF6 (1-butyl-3-methylimidazolium hexafluoraphosphate) is introduced into the ionic liquids-rich phase of ILATPS containing penicillin and converses it into MILWS. Penicillin is hydrolyzed by penicillin acylase in the water phase of MILWS at pH 5. The byproduct phenylacetic acid (PAA) is partitioned into the ionic liquids mixture phase, while the intended product 6-aminopenicillanic acid (6-APA) is precipitated at this pH. In comparison with a similar butyl acetate/water system (BAWS) at pH 4, MILWS exhibits two advantages. (1) The selectivity between PAA and penicillin is greatly optimized at pH 5 by varying the mole ratio of [C4mim]PF6/[C4mim]BF4 in MILWS, whereas in BAWS the unalterable nature of the organic solvent restricts the optimized pH for maximum selectivity between PAA and penicillin at pH 4. (2) The pH for 6-APA precipitation in BAWS is 4, whereas it shifts to pH 5 in MILWS due to the complexation between negatively charged 6-APA and the cationic surface of the ionic liquids micelle. As a result, the removal of the two products from the enzyme sphere at relatively high pH is permitted in MILWS, which is beneficial for enzymatic activity and stability in comparison with the acidic pH 4 environment in BAWS.

  16. Vaginal Absorption of Penicillin.

    PubMed

    Rock, J; Barker, R H; Bacon, W B

    1947-01-01

    Except during the last two months of pregnancy, penicillin is easily absorbed from cocoa butter suppositories in the vagina, ordinarily to give therapeutic blood levels for from 4 to 6 hours. Penicillin in the dosage used seems to have a good effect on vaginal infections. In nonpregnant women, during the ovulation phase, considered as including days 14 +/- 2 in the ordinary menstrual cycle of about 28 days, absorption seemed to be somewhat diminished. Higher levels were found in patients who were near the end of their menstrual cycles and in two patients who were menopausal. Patients who were very near term absorbed little or no penicillin, whereas patients 10 days post partum showed excellent absorption.

  17. Morphological, physiological and enzymatic characteristics of cephalosporin acylase-producing Arthrobacter strain 45-8A.

    PubMed

    Zhang, Q J; Xu, W X

    1993-01-01

    A bacterial strain producing cephalosporin acylases was isolated from soil. The morphological and physiological properties of this strain suggest that it belongs to the genus Arthrobacter, and the isolate was therefore designated Arthrobacter strain 45-8A. Substrate specificity of the enzyme was examined. The enzyme can convert both cephalosporin acid to 7-aminocephalosporanic acid. An interesting feature of the acylases is their temperature-dependent regulation. Activity of acylases was detected in strain 45-8A grown at temperature below 30 degrees C, but was not observed at higher temperature. Arthrobacter strain 45-8A did not exhibit beta-lactamase activity, even though its resistance to cephalosporin C was very strong (> 2000 micrograms/ml). This is quite beneficial for its application in the manufacture of 7-aminocephalosporanic acid. PMID:8484708

  18. Piezoelectric immunosensors for the detection of individual antibiotics and the total content of penicillin antibiotics in foodstuffs.

    PubMed

    Karaseva, N A; Ermolaeva, T N

    2014-03-01

    Piezoelectric immunosensors on the basis of homologous and group-specificantibodies have been developed for detecting penicillin G, ampicillin, and the total content of penicillin antibiotics. The receptor coating of the sensor was obtained by the immobilization of penicillin G or ampicillin hapten-protein conjugates on the polypyrrole film obtained by electropolymerization and activated by glutaraldehyde. The affinity constants and the cross reactivity coefficients have been calculated. This made it possible to estimate the affinity and specificity of the polyclonal and monoclonal antibodies used. The calibration curves are linear in the range of concentrations 2.5-250.0 ng ml(-1) (penicillin G), 2.5-500.0 ng ml(-1) (ampicillin), and 1-500 ng ml(-1) (group of penicillin). The limits of detection are 0.8 ng ml(-1), 3.9 ng ml(-1), which are lower than MRL, established for penicillin antibiotics. The sensors were tested in detecting penicillins in milk, pork, beef, liver.

  19. 21 CFR 211.176 - Penicillin contamination.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 4 2013-04-01 2013-04-01 false Penicillin contamination. 211.176 Section 211.176... Penicillin contamination. If a reasonable possibility exists that a non-penicillin drug product has been exposed to cross-contamination with penicillin, the non-penicillin drug product shall be tested for...

  20. 21 CFR 558.460 - Penicillin.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Penicillin. 558.460 Section 558.460 Food and Drugs... Animal Feeds § 558.460 Penicillin. (a) Specifications. As penicillin procaine G or feed grade penicillin.... (1) It is used as follows: Penicillin in grams per ton Combination in grams per ton Indications...

  1. 21 CFR 558.460 - Penicillin.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Penicillin. 558.460 Section 558.460 Food and Drugs... Animal Feeds § 558.460 Penicillin. (a) Specifications. As penicillin procaine G or feed grade penicillin.... (1) It is used as follows: Penicillin in grams per ton Combination in grams per ton Indications...

  2. 21 CFR 211.176 - Penicillin contamination.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 4 2011-04-01 2011-04-01 false Penicillin contamination. 211.176 Section 211.176... Penicillin contamination. If a reasonable possibility exists that a non-penicillin drug product has been exposed to cross-contamination with penicillin, the non-penicillin drug product shall be tested for...

  3. 21 CFR 211.176 - Penicillin contamination.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Penicillin contamination. 211.176 Section 211.176... Penicillin contamination. If a reasonable possibility exists that a non-penicillin drug product has been exposed to cross-contamination with penicillin, the non-penicillin drug product shall be tested for...

  4. 21 CFR 211.176 - Penicillin contamination.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 4 2012-04-01 2012-04-01 false Penicillin contamination. 211.176 Section 211.176... Penicillin contamination. If a reasonable possibility exists that a non-penicillin drug product has been exposed to cross-contamination with penicillin, the non-penicillin drug product shall be tested for...

  5. 21 CFR 558.460 - Penicillin.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Penicillin. 558.460 Section 558.460 Food and Drugs... Animal Feeds § 558.460 Penicillin. (a) Specifications. As penicillin procaine G or feed grade penicillin.... (1) It is used as follows: Penicillin in grams per ton Combination in grams per ton Indications...

  6. 21 CFR 558.460 - Penicillin.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Penicillin. 558.460 Section 558.460 Food and Drugs... Animal Feeds § 558.460 Penicillin. (a) Specifications. As penicillin procaine G or feed grade penicillin.... (1) It is used as follows: Penicillin in grams per ton Combination in grams per ton Indications...

  7. 21 CFR 211.176 - Penicillin contamination.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 4 2014-04-01 2014-04-01 false Penicillin contamination. 211.176 Section 211.176... Penicillin contamination. If a reasonable possibility exists that a non-penicillin drug product has been exposed to cross-contamination with penicillin, the non-penicillin drug product shall be tested for...

  8. 21 CFR 558.460 - Penicillin.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Penicillin. 558.460 Section 558.460 Food and Drugs... Animal Feeds § 558.460 Penicillin. (a) Specifications. As penicillin procaine G or feed grade penicillin.... (1) It is used as follows: Penicillin in grams per ton Combination in grams per ton Indications...

  9. Fatty acid hydrolysis of acyl marinobactin siderophores by Marinobacter acylases.

    PubMed

    Kem, Michelle P; Naka, Hiroaki; Iinishi, Akira; Haygood, Margo G; Butler, Alison

    2015-01-27

    The marine bacteria Marinobacter sp. DS40M6 and Marinobacter nanhaiticus D15-8W produce a suite of acyl peptidic marinobactin siderophores to acquire iron under iron-limiting conditions. During late-log phase growth, the marinobactins are hydrolyzed to form the marinobactin headgroup with release of the corresponding fatty acid tail. The bntA gene, a homologue of the Pseudomonas aeruginosa pyoverdine acylase gene, pvdQ, was identified from Marinobacter sp. DS40M6. A bntA knockout mutant of Marinobacter sp. DS40M6 produced the suite of acyl marinobactins A-E, without the usual formation of the marinobactin headgroup. Another marinobactin-producing species, M. nanhaiticus D15-8W, is predicted to have two pvdQ homologues, mhtA and mhtB. MhtA and MhtB have 67% identical amino acid sequences. MhtA catalyzes hydrolysis of the apo-marinobactin siderophores as well as the quorum sensing signaling molecule, dodecanoyl-homoserine lactone. In contrast to hydrolysis of the suite of apo-marinobactins by MhtA, hydrolysis of the iron(III)-bound marinobactins was not observed. PMID:25588131

  10. The Molecular Structure of Penicillin

    NASA Astrophysics Data System (ADS)

    Bentley, Ronald

    2004-10-01

    The chemical structure of penicillin was determined between 1942 and 1945 under conditions of secrecy established by the U.S. and U.K. governments. The evidence was not published in the open literature but as a monograph. This complex volume does not present a structure proof that can be readily comprehended by a student. In this article, a basic structural proof for the penicillin molecule is provided, emphasizing the chemical work. The stereochemistry of penicillin is also described, and various rearrangements are considered on the basis of the accepted β-lactam structure.

  11. 21 CFR 556.510 - Penicillin.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Penicillin. 556.510 Section 556.510 Food and Drugs... Residues of New Animal Drugs § 556.510 Penicillin. Tolerances are established for residues of penicillin and the salts of penicillin in food as follows: (a) 0.05 part per million (negligible residue) in...

  12. 21 CFR 556.510 - Penicillin.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Penicillin. 556.510 Section 556.510 Food and Drugs... Residues of New Animal Drugs § 556.510 Penicillin. Tolerances are established for residues of penicillin and the salts of penicillin in food as follows: (a) 0.05 part per million (negligible residue) in...

  13. 21 CFR 556.510 - Penicillin.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Penicillin. 556.510 Section 556.510 Food and Drugs... Residues of New Animal Drugs § 556.510 Penicillin. Tolerances are established for residues of penicillin and the salts of penicillin in food as follows: (a) 0.05 part per million (negligible residue) in...

  14. 21 CFR 556.510 - Penicillin.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Penicillin. 556.510 Section 556.510 Food and Drugs... Residues of New Animal Drugs § 556.510 Penicillin. Tolerances are established for residues of penicillin and the salts of penicillin in food as follows: (a) 0.05 part per million (negligible residue) in...

  15. 21 CFR 556.510 - Penicillin.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Penicillin. 556.510 Section 556.510 Food and Drugs... Residues of New Animal Drugs § 556.510 Penicillin. Tolerances are established for residues of penicillin and the salts of penicillin in food as follows: (a) 0.05 part per million (negligible residue) in...

  16. 21 CFR 520.1696a - Buffered penicillin powder, penicillin powder with buffered aqueous diluent.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Buffered penicillin powder, penicillin powder with... FORM NEW ANIMAL DRUGS § 520.1696a Buffered penicillin powder, penicillin powder with buffered aqueous diluent. (a) Specifications. When reconstituted, each milliliter contains penicillin G procaine...

  17. 21 CFR 520.1696a - Buffered penicillin powder, penicillin powder with buffered aqueous diluent.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Buffered penicillin powder, penicillin powder with... FORM NEW ANIMAL DRUGS § 520.1696a Buffered penicillin powder, penicillin powder with buffered aqueous diluent. (a) Specifications. When reconstituted, each milliliter contains penicillin G procaine...

  18. The Molecular Structure of Penicillin

    ERIC Educational Resources Information Center

    Bentley, Ronald

    2004-01-01

    Overviews of the observations that constitute a structure proof for penicillin, specifically aimed at the general student population, are presented. Melting points and boiling points were criteria of purity and a crucial tool was microanalysis leading to empirical formulas.

  19. Pickles, pectin, and penicillin.

    PubMed

    Demain, Arnold L

    2004-01-01

    My professional life has been devoted to the study of microbial products and their biosynthesis, regulation, and overproduction. These have included primary metabolites (glutamic acid, tryptophan, inosinic acid, guanylic acid, vitamin B(12), riboflavin, pantothenic acid, ethanol, and lactic acid) and secondary metabolites (penicillin, cephalosporins, streptomycin, fosfomycin, gramicidin S, rapamycin, indolmycin, microcin B17, fumagillin, mycotoxins, Monascus pigments, and tetramethylpyrazine). Other areas included microbial nutrition, strain improvement, bioconversions of statins and beta-lactams, sporulation and germination, plasmid stability, gel microdroplets, and the production of double-stranded RNA, the polymer xanthan, and enzymes (polygalacturonase, protease, cellulase). Most of the studies were carried out with me by devoted and hardworking industrial scientists for 15 years at Merck & Co. and by similarly characterized students, postdoctorals, and visiting scientists during my 32 years at the Massachusetts Institute of Technology. I owe much of my success to my mentors from academia and industry. My recent research activities with undergraduate students at the Charles A. Dana Research Institute for Scientists Emeriti (R.I.S.E.) at Drew University have been very rewarding and are allowing me to continue my career. PMID:15487928

  20. Pickles, pectin, and penicillin.

    PubMed

    Demain, Arnold L

    2004-01-01

    My professional life has been devoted to the study of microbial products and their biosynthesis, regulation, and overproduction. These have included primary metabolites (glutamic acid, tryptophan, inosinic acid, guanylic acid, vitamin B(12), riboflavin, pantothenic acid, ethanol, and lactic acid) and secondary metabolites (penicillin, cephalosporins, streptomycin, fosfomycin, gramicidin S, rapamycin, indolmycin, microcin B17, fumagillin, mycotoxins, Monascus pigments, and tetramethylpyrazine). Other areas included microbial nutrition, strain improvement, bioconversions of statins and beta-lactams, sporulation and germination, plasmid stability, gel microdroplets, and the production of double-stranded RNA, the polymer xanthan, and enzymes (polygalacturonase, protease, cellulase). Most of the studies were carried out with me by devoted and hardworking industrial scientists for 15 years at Merck & Co. and by similarly characterized students, postdoctorals, and visiting scientists during my 32 years at the Massachusetts Institute of Technology. I owe much of my success to my mentors from academia and industry. My recent research activities with undergraduate students at the Charles A. Dana Research Institute for Scientists Emeriti (R.I.S.E.) at Drew University have been very rewarding and are allowing me to continue my career.

  1. Simulated Batch Production of Penicillin

    ERIC Educational Resources Information Center

    Whitaker, A.; Walker, J. D.

    1973-01-01

    Describes a program in applied biology in which the simulation of the production of penicillin in a batch fermentor is used as a teaching technique to give students experience before handling a genuine industrial fermentation process. Details are given for the calculation of minimum production cost. (JR)

  2. Genomic Analysis Reveals Versatile Organisms for Quorum Quenching Enzymes: Acyl-Homoserine Lactone-Acylase and -Lactonase

    PubMed Central

    Kalia, Vipin Chandra; Raju, Sajan C; Purohit, Hemant J

    2011-01-01

    Microbial virulence and their resistance to multiple drugs have obliged researchers to look for novel drug targets. Virulence of pathogenic microbes is regulated by signal molecules such as acylated homoserine lactone (AHL) produced during a cell density dependent phenomenon of quorum sensing (QS). In contrast, certain microbes produce AHL-lactonases and -acylases to degrade QS signals, also termed as quorum quenching. Mining sequenced genome databases has revealed organisms possessing conserved domains for AHL-lactonases and –acylases: i) Streptomyces (Actinobacteria), ii) Deinococcus (Deinococcus-Thermus), iii) Hyphomonas (α-Proteobacteria), iv) Ralstonia (β-Proteobacteria), v) Photorhabdus (γ-Proteobacteria), and certain marine gamma proteobacterium. Presence of genes for both the enzymes within an organism was observed in the following: i) Deinococcus radiodurans R1, ii) Hyphomonas neptunium ATCC 15444 and iii) Photorhabdus luminescens subsp. laumondii TTO1. These observations are supported by the presence motifs for lactonase and acylase in these strains. Phylogenetic analysis and multiple sequence alignment of the gene sequences for AHL-lactonases and –acylases have revealed consensus sequences which can be used to design primers for amplifying these genes even among mixed cultures and metagenomes. Quorum quenching can be exploited to prevent food spoilage, bacterial infections and bioremediation. PMID:21660112

  3. Penicillin and the reconstruction of Japan.

    PubMed

    Cozzoli, Daniele

    2014-01-01

    This paper explores postwar American strategies regarding penicillin in Japan. Perceived as both an American gift and a symbol of reconstruction, penicillin played a singular role in Washington's postwar policies towards Europe and Japan. Washington encouraged US pharmaceutical companies to penetrate Europe but sought to protect intra-European trade. In Japan, however, importing penicillin from the US or establishing private American factories was forbidden. Jackson W. Foster implemented a smaller-scale, military-directed version of the US's wartime penicillin project. In this paper, it is argued that the MacArthur administration aimed to boost Japanese penicillin production and transfer American industrial culture to Japan. This was initially a major success. However, the Japanese pharmaceutical industry failed to break down barriers to market entry established by first movers and, consequently, was uncompetitive throughout the twentieth century. This paper regards the American penicillin project in Japan as a factor in the weakness of the postwar Japanese pharmaceutical industry. PMID:26054211

  4. Immobilization of whole cells using polymeric coatings

    SciTech Connect

    Lawton, C.W.; Klei, H.E.; Sunstrom, D.V.; Voronka, P.J.; Scott, C.D.

    1986-01-01

    A cell immobilization procedure was developed using latex coatings on solid particles. The method's widespread applicability has been demonstrated by successfully immobilizing Saccharomyces cerevisiae (ethanol production), Bacillus subtilis (tryptophan production). Penicillium chrysogenum (penicillin G production), and Escherichia coli (aspartic acid production). In contrast to other immobilization methods, this procedure produces a pellicular particle that is porous, allowing rapid substrate and gas transfer, has a hard core to avoid compression in large beds, and is dense to allow use in fluidized beds. The immobilization procedure was optimized with S. cerevisiae. Kinetic constants obtained were used to calculate effectiveness factors to show that there was minimal intraparticle diffusion resistance. Reactors utilizing the optimized particles were run for 300 hours to evaluate immobilized particle half-life which was 250 hours.

  5. What if Fleming had not discovered penicillin?

    PubMed

    Alharbi, Sulaiman Ali; Wainwright, Milton; Alahmadi, Tahani Awad; Salleeh, Hashim Bin; Faden, Asmaa A; Chinnathambi, Arunachalam

    2014-09-01

    What would have happened had Alexander Fleming not discovered penicillin in 1928? Perhaps the obvious answer is that, someone else would have discovered penicillin during 1930s and the Oxford group, would still have purified it sometime in the early 1940s. Here, however, in this counterfactual account of the penicillin story, it is argued that without Fleming, penicillin might still be undiscovered and the antibiotic age would never have dawned. As a result, many of the recent developments in medicine, such as organ transplantation, might have been delayed or, at best, made more hazardous. Penicillin might have come onto the scene a few years later but, had Fleming overlooked the discovery, it seems certain that penicillin would not have saved countless Allied lives, during and after D-Day. Instead of having enjoyed fifty and more years of the antibiotic age, it is argued here, that we would have had to rely upon highly developed sulphonamides, so-called "supasulfas", and other chemically-derived antibacterial drugs. Indeed, it might be the case that, even well into this new millennium, the antibiotic age has yet to dawn, and medicine is still waiting for someone to chance upon penicillin. Here we discuss what might have happened had Fleming not discovered penicillin and come to the conclusion that the medical armoury available today would have been far different and might have relied solely upon highly developed varieties of sulphonamides or similar, synthetic, non-antibiotic antibacterial agents. PMID:25183937

  6. 21 CFR 520.1696 - Penicillin.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Penicillin. 520.1696 Section 520.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1696 Penicillin....

  7. 21 CFR 520.1696 - Penicillin.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Penicillin. 520.1696 Section 520.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1696 Penicillin....

  8. What if Fleming had not discovered penicillin?

    PubMed Central

    Alharbi, Sulaiman Ali; Wainwright, Milton; Alahmadi, Tahani Awad; Salleeh, Hashim Bin; Faden, Asmaa A.; Chinnathambi, Arunachalam

    2014-01-01

    What would have happened had Alexander Fleming not discovered penicillin in 1928? Perhaps the obvious answer is that, someone else would have discovered penicillin during 1930s and the Oxford group, would still have purified it sometime in the early 1940s. Here, however, in this counterfactual account of the penicillin story, it is argued that without Fleming, penicillin might still be undiscovered and the antibiotic age would never have dawned. As a result, many of the recent developments in medicine, such as organ transplantation, might have been delayed or, at best, made more hazardous. Penicillin might have come onto the scene a few years later but, had Fleming overlooked the discovery, it seems certain that penicillin would not have saved countless Allied lives, during and after D-Day. Instead of having enjoyed fifty and more years of the antibiotic age, it is argued here, that we would have had to rely upon highly developed sulphonamides, so-called “supasulfas”, and other chemically-derived antibacterial drugs. Indeed, it might be the case that, even well into this new millennium, the antibiotic age has yet to dawn, and medicine is still waiting for someone to chance upon penicillin. Here we discuss what might have happened had Fleming not discovered penicillin and come to the conclusion that the medical armoury available today would have been far different and might have relied solely upon highly developed varieties of sulphonamides or similar, synthetic, non-antibiotic antibacterial agents. PMID:25183937

  9. What if Fleming had not discovered penicillin?

    PubMed

    Alharbi, Sulaiman Ali; Wainwright, Milton; Alahmadi, Tahani Awad; Salleeh, Hashim Bin; Faden, Asmaa A; Chinnathambi, Arunachalam

    2014-09-01

    What would have happened had Alexander Fleming not discovered penicillin in 1928? Perhaps the obvious answer is that, someone else would have discovered penicillin during 1930s and the Oxford group, would still have purified it sometime in the early 1940s. Here, however, in this counterfactual account of the penicillin story, it is argued that without Fleming, penicillin might still be undiscovered and the antibiotic age would never have dawned. As a result, many of the recent developments in medicine, such as organ transplantation, might have been delayed or, at best, made more hazardous. Penicillin might have come onto the scene a few years later but, had Fleming overlooked the discovery, it seems certain that penicillin would not have saved countless Allied lives, during and after D-Day. Instead of having enjoyed fifty and more years of the antibiotic age, it is argued here, that we would have had to rely upon highly developed sulphonamides, so-called "supasulfas", and other chemically-derived antibacterial drugs. Indeed, it might be the case that, even well into this new millennium, the antibiotic age has yet to dawn, and medicine is still waiting for someone to chance upon penicillin. Here we discuss what might have happened had Fleming not discovered penicillin and come to the conclusion that the medical armoury available today would have been far different and might have relied solely upon highly developed varieties of sulphonamides or similar, synthetic, non-antibiotic antibacterial agents.

  10. 21 CFR 520.1696d - Penicillin V potassium tablets.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Penicillin V potassium tablets. 520.1696d Section... Penicillin V potassium tablets. (a) Specifications. Each tablet contains penicillin V potassium equivalent to 125 milligrams (200,000 units) or 250 milligrams (400,000 units) of penicillin V. (b) Sponsors....

  11. 21 CFR 558.155 - Chlortetracycline, sulfathiazole, penicillin.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Chlortetracycline, sulfathiazole, penicillin. 558... Specific New Animal Drugs for Use in Animal Feeds § 558.155 Chlortetracycline, sulfathiazole, penicillin... percent (20 grams) sulfathiazole, and procaine penicillin equivalent to 10 grams of penicillin per...

  12. 21 CFR 558.155 - Chlortetracycline, sulfathiazole, penicillin.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Chlortetracycline, sulfathiazole, penicillin. 558... Specific New Animal Drugs for Use in Animal Feeds § 558.155 Chlortetracycline, sulfathiazole, penicillin... percent (20 grams) sulfathiazole, and procaine penicillin equivalent to 10 grams of penicillin per...

  13. 21 CFR 558.155 - Chlortetracycline, sulfathiazole, penicillin.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Chlortetracycline, sulfathiazole, penicillin. 558... Specific New Animal Drugs for Use in Animal Feeds § 558.155 Chlortetracycline, sulfathiazole, penicillin... percent (20 grams) sulfathiazole, and procaine penicillin equivalent to 10 grams of penicillin per...

  14. Effect of dissolved carbon dioxide on penicillin fermentations: mycelial growth and penicillin production. [Penicillium chrysogenum

    SciTech Connect

    Ho, C.S.; Smith, M.D.

    1986-01-01

    The effect of dissolved carbon dioxide on the specific growth rate and the penicillin production rate of Penicillium chrysogenum was examined experimentally. The dissolved carbon dioxide was found to inhibit the specific growth rate and the penicillin production rate when the aerated submerged penicillin fermentation was exposed to influent gases of 12.6 and 20% carbon dioxide, respectively. Upon exposure to influent gases of 3 and 5% carbon dioxide, no pronounced metabolic inhibition was noted.

  15. [Evaluation of penicillin expandase mutants and complex substrate inhibition characteristics at high concentrations of penicillin G].

    PubMed

    Wu, Linjun; Fan, Keqiang; Ji, Junjie; Yang, Keqian

    2015-12-01

    Penicillin expandase, also known as deacetoxycephalosporin C synthase (DAOCS), is an essential enzyme involved in cephalosporin C biosynthesis. To evaluate the catalytic behaviors of penicillin expandase under high penicillin G concentration and to identify mutants suitable for industrial applications, the specific activities of wild-type DAOCS and several mutants with increased activities toward penicillin G were determined by HPLC under high penicillin G concentrations. Their specific activity profiles were compared with theoretical predictions by different catalytic dynamics models. We evaluated the specific activities of wild-type DAOCS and previous reported high-activity mutants H4, H5, H6 and H7 at concentrations ranging from 5.6 to 500 mmol/L penicillin G. The specific activities of wild-type DAOCS and mutant H4 increased as penicillin G concentration increased, but decreased when concentrations of substrate go above 200 mmol/L. Other mutants H5, H6 and H7 showed more complex behaviors under high concentration of penicillin G. Among all tested enzymes, mutant H6 showed the highest activity when concentration of penicillin G is above 100 mmol/L. Our results revealed that the substrate inhibition to wild-type DAOCS' by penicillin G is noncompetitive. Other DAOCS mutants showed more complex trends in their specific activities at high concentration of penicillin G (>100 mmol/L), indicating more complex substrate inhibition mechanism might exist. The substrate inhibition and activity of DAOCS mutants at high penicillin G concentration provide important insight to help select proper mutants for industrial application. PMID:27093832

  16. Routine Penicillin Skin Testing in Hospitalized Patients with a History of Penicillin Allergy

    PubMed Central

    Macy, Eric; Roppe, Linda B; Schatz, Michael

    2004-01-01

    Background: In selected inpatient settings, penicillin skin testing has been shown to affect antibiotic use. Routine penicillin skin testing has not been studied in hospitalized patients with a history of penicillin allergy. Objectives: To determine whether routine penicillin skin testing at a large regional hospital affected antibiotic use and/or antibiotic side effects in hospitalized persons with a history of penicillin allergy. Methods: A convenience sample of patients was penicillin skin tested from among those who had a history of penicillin allergy during any hospitalization from September 2002 through February 2003. Discharge coding was used to identify two age- and sex-matched control patients who had a history of penicillin allergy but who did not receive skin testing while hospitalized. All inpatient and outpatient antibiotic use, positive results of bacteriology culture obtained at any time from August 2002 through March 2003, and coded adverse reactions to medications were identified. Results: Of the 13,172 patients admitted to the hospital during the study period, 1627 (12.35%) had a history of penicillin allergy; of these 1627 patients, 141 (8.7%) received skin testing. Use of antibiotic agents was common: 79.4% of all study subjects received at least one antibiotic agent. Penicillins were used in substantially more cases than controls. Cephalosporins were the most widely used class of antibiotic agents, accounting for 26.8% of all antibiotic courses used. Of the six antibiotic-associated adverse drug reactions in five (1.2%) of the study subjects, one adverse reaction was associated with a penicillin, and one was associated with a cephalosporin. Conclusions: Routine penicillin skin testing in hospitalized patients is safe and allows more appropriate antibiotic use. To ensure that accurate information is available to support clinical care, hospitals should maintain a single centralized system for collecting data on drug allergy and testing. PMID

  17. 21 CFR 520.1696a - Buffered penicillin powder, penicillin powder with buffered aqueous diluent.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... disease (air-sac infection) and bluecomb (nonspecific infectious enteritis). (ii) Limitations. As... infectious enteritis). (ii) Limitations. As penicillin G procaine; not for use in laying chickens;...

  18. Pharmacokinetics of the penicillins in man.

    PubMed

    Barza, M; Weinstein, L

    1976-01-01

    The purpose of this article is to review and summarise those aspects of the pharmacokinetic behaviour of the penicillins that may be of particular interest to the clinician. While these antibiotics differ markedly in their acid stability and oral absorption, misleading inferences may be drawn from simple inspection of the maximal serum concentrations produced by a given dose administered orally. A more accurate picture emerges when serum protein binding and intrinsic activity of the drugs are taken into account. All of the penicillins are readily and actively secreted by the renal tubles and most are eliminated, almost completely unchanged, in the urine. The majority are excreted in small quantities in the bile, but this is a major route for elimination of nafcillin from the body. Distribution of the penicillins in 'non-specialised' sites is excellent. In contrast, penetration of the central nevous system and eye are poor, and of the prostate, minimal. Inflammation reduces the barries to penetration of these areas. However, quantitative data related to this phenomenon in man are few. Probenecid actively competes with the 'export' pump of the meninges and renal tubular cells. This results in an increase in concentrations of the penicillins in the blood and cerebrospinal fluid. The effect of this agent on active secretion of these antibiotics from the eye and biliary tract is minimal. While elimination of the penicillins from the body takes place largely via renal excretion, penicillin V and oxacillin are extensively degraded as well. In contrast to the situation with respect to 'natural' and 'broad-spectrum' penicillins, the serum half-life of the isoxazolyl congeners and nafcillin is only minimally prolonged in the presence of renal failure. These agents are only weakly haemodialyzable, while the other penicillins are rapidly removed from the circulation by this procedure. PMID:797501

  19. Fiber Optic Chemical Sensors Using Immobilized Bioreceptors

    NASA Astrophysics Data System (ADS)

    Walt, David R.; Luo, Shufang; Munkholm, Christiane

    1988-06-01

    Optrodes employing immobilized enzymes were developed using covalent attachment of sensor reagents. This development is an extension of the original application of this sensor technology in which a pH sensor was constructed with the pH sensitive dye fluorescein incorporated into a polymer covalently attached to the fiber tip. This sensor displayed significantly improved response times over previous fiber optic sensors because of reduced diffusion limitations. In addition, the signal intensities were greatly enhanced by the high concentration of fluorescent dye localized at the fiber tip. With the anticipation that these qualities would be preserved, a class of sensors based on the immobilization of biomolecules in the polymer matrix became the next goal. This paper will first describe a fiber optic probe prepared by immobilizing esterase in a crosslinked polyacrylamide matrix. The immobilized esterase converts the nonfluorescent fluoresceindiacetate into fluorescein. Both the steady state level and kinetic generation of fluorescence can be related to the concentration of fluoresceindiacetate. A fiber optic sensor for penicillin has been made by coimmobili zing penicillinase with a pH sensitive fluorescent dye. Penicillinase converts penicillin to penicilloic acid which produces a microenvironmental pH change in the dye-containing polymer matrix resulting in a concommitant change in fluorescence. The change in fluorescence is proportional to the concentration of penicillin and a 95% response is reached in 40-60 seconds. The sensor has a detection limit of 2.5 x 10-4 M. Another class of sensors using immobilized bioreceptors will be based on the principles of fluoroimmunoassay. This paper will discuss some basic principles and problems of 1) fluorescence quenching immunoassays, 2) fluorescence excitation transfer immunoassays, and 3) energy transfer immunoassays for digoxin. Both advantages and inherent problems for these sensor preparations will be addressed.

  20. The acylase PvdQ has a conserved function among fluorescent Pseudomonas spp.

    PubMed

    Koch, Gudrun; Nadal Jimenez, Pol; Muntendam, Remco; Chen, Yixi; Papaioannou, Evelina; Heeb, Stephan; Cámara, Miguel; Williams, Paul; Cool, Robbert H; Quax, Wim J

    2010-06-01

    Pyoverdine biosynthesis in fluorescent Pseudomonas spp. and especially in the opportunistic human pathogen Pseudomonas aeruginosa has been extensively studied. The acylase PvdQ is required for a maturation step in pyoverdine biosynthesis but also has been proven to be effective in degrading long-chain N-acyl homoserine lactones (AHLs). These molecules are used as quorum-sensing molecules by Gram-negative bacteria such as Pseudomonads themselves. Interestingly, the pvdQ gene is part of a pyoverdine cluster in P. aeruginosa and P. syringae but not in other fluorescent Pseudomonas spp. In this study we have compared the activities of PvdQ orthologues from various species and provide evidence for conserved functions in Pseudomonas fluorescens PfO-1, P. putida KT2440 and P. aeruginosa PA14. Despite large differences in genomic organization, expression of each of these pvdQ orthologues is regulated by iron availability. Moreover, PvdQ and its orthologues have conserved substrate specificity for AHLs and play a role in pyoverdine production in all tested Pseudomonas species. These data strongly suggest that the role of PvdQ in pyoverdine biosynthesis is conserved among Pseudomonas spp., while the control that PvdQ exerts in P. aeruginosa over its own quorum-sensing signals seems to be unique to this bacterium. PMID:23766117

  1. [Penicillin in Belgium 1945-1952].

    PubMed

    Billiau, A

    2009-01-01

    Penicillin, discovered now eighty years ago (1929) by Alexander Fleming in London, was developed during the world war II into a revolutionizing drug by Howard Florey and Michael Chain in Oxford. At first, industrial production of penicillin was exclusively in the hands of a consortium of large U.S. pharmaceutical companies. However, the war being ended, European entrepreneurs likewise ventured to set up penicillin production units. Amongst them, in Belgium, was Jacques Lannoye, director and co-owner of 'Papeteries de Genval' and of a modest pharmaceutical company, called 'Soprolac'. Through his connections with several medical faculty professors of the Catholic University of Leuven, Lannoye came in touch with Piet De Somer, then a young researcher at the Leuven 'Institute of Bacteriology', with an interest in production of penicillin. A years-long collaboration followed, from which emerged a booming antibiotic and vaccine factory, 'RIT' (Recherche et Industrie Thérapeutiques) in Genval, as well an industry-supported research laboratory, the later Rega Institute, at the University of Leuven. From 1947 to 1952, while coping with the practical problems of setting up large-scale production of penicillin, De Somer maintained a lively correspondence with some other players in the field, sharing with them the ups and downs of the enterprise. Fortunately these letters have been preserved in the archives of the Rega Institute, such that they allow for a reconstruction of this interesting episode in the medical history of Belgium. PMID:20084833

  2. Alexander Fleming: the spectrum of penicillin.

    PubMed

    Sternbach, G; Varon, J

    1992-01-01

    The discovery of penicillin was directly linked to the inhibition by that agent of the growth of colonies of staphylococcus. However, subsequent resistance by this organism to penicillin as well as to a number of other agents has marked the history of staphylococcus in the antibiotic era. One of the most important mechanisms of this resistance has been the production of penicillinase, an enzyme that inactivates penicillin and related antibiotics. Penicillinase is currently termed beta-lactamase, and it is now recognized that there are several types of beta-lactamases produced by various organisms. The ability of staphylococci to produce this enzyme has been countered by the development of penicillinase-resistant agents and the addition of beta-lactamase inhibitors to antibiotics.

  3. Relative penicillin G resistance in Neisseria meningitidis and reduced affinity of penicillin-binding protein 3.

    PubMed Central

    Mendelman, P M; Campos, J; Chaffin, D O; Serfass, D A; Smith, A L; Sáez-Nieto, J A

    1988-01-01

    We examined clinical isolates of Neisseria meningitidis relatively resistant to penicillin G (mean MIC, 0.3 micrograms/ml; range, 0.1 to 0.7 micrograms/ml), which were isolated from blood and cerebrospinal fluid for resistance mechanisms, by using susceptible isolates (mean MIC, less than or equal to 0.06 micrograms/ml) for comparison. The resistant strains did not produce detectable beta-lactamase activity, otherwise modify penicillin G, or bind less total penicillin. Penicillin-binding protein (PBP) 3 of the six resistant isolates tested uniformly bound less penicillin G in comparison to the same PBP of four susceptible isolates. Reflecting the reduced binding affinity of PBP 3 of the two resistant strains tested, the amount of 3H-labeled penicillin G required for half-maximal binding was increased in comparison with that of PBP 3 of the two susceptible isolates. We conclude that the mechanism of resistance in these meningococci relatively resistant to penicillin G was decreased affinity of PBP 3. Images PMID:3134848

  4. One-week oral challenge with penicillin in diagnosis of penicillin allergy.

    PubMed

    Hjortlund, Janni; Mortz, Charlotte Gotthard; Skov, Per Stahl; Eller, Esben; Poulsen, Johan Milling; Borch, Jakob Eli; Bindslev-Jensen, Carsten

    2012-05-01

    Many patients experience reactions during penicillin treatment. The diagnosis may be difficult and is mainly based on short-term tests. The European Network for Drug Allergy (ENDA) guidelines proposed for diagnosing penicillin allergy do not include long-term challenge. In this study a total of 405 patients were evaluated. The ENDA guidelines were extended, to include a 7-day oral treatment (p.o.7) with penicillin for all patients who were negative in the ENDA programme. Among the 405 patients; 85 had an immediate reaction to penicillin, and a further 13 reacted during p.o.7. Among the 307 patients with a negative outcome, 88 had a case history of reaction to other β-lactam antibiotics and were subsequently tested with the culprit drug. Thirteen patients had a positive outcome: 3 on single-dose challenge and 10 during p.o.7. The extended penicillin diagnostic work-up was positive in 111 patients, 30.0% showed immediate reactions and 5.7% reacted during p.o.7. Approximately 20% of all patients with positive outcome during penicillin challenge are detected by adding p.o.7 with penicillin to the original ENDA guidelines.

  5. Microorganism immobilization

    DOEpatents

    Compere, Alicia L.; Griffith, William L.

    1981-01-01

    Live metabolically active microorganisms are immobilized on a solid support by contacting particles of aggregate material with a water dispersible polyelectrolyte such as gelatin, crosslinking the polyelectrolyte by reacting it with a crosslinking agent such as glutaraldehyde to provide a crosslinked coating on the particles of aggregate material, contacting the coated particles with live microorganisms and incubating the microorganisms in contact with the crosslinked coating to provide a coating of metabolically active microorganisms. The immobilized microorganisms have continued growth and reproduction functions.

  6. Depletion of penicillin G residues in sows after intramuscular injection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A penicillin G procaine residue depletion study was conducted in heavy sows to estimate the pre-slaughter withdrawal periods necessary to clear penicillin from kidney and muscle. Heavy sows (n = 126) were treated with penicillin G procaine at a 5x dose (33,000 IU/kg) for 3 consecutive days by intra...

  7. 21 CFR 520.1696d - Penicillin V tablets.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Penicillin V tablets. 520.1696d Section 520.1696d... DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1696d Penicillin V tablets. (a) Specifications. Each tablet contains penicillin V potassium equivalent to 125 milligrams...

  8. 21 CFR 526.1696a - Penicillin G procaine.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Penicillin G procaine. 526.1696a Section 526.1696a... DRUGS, FEEDS, AND RELATED PRODUCTS INTRAMAMMARY DOSAGE FORM NEW ANIMAL DRUGS § 526.1696a Penicillin G procaine. (a) Specifications. Each 10-milliliter single-dose syringe contains penicillin G...

  9. 21 CFR 520.1696d - Penicillin V tablets.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Penicillin V tablets. 520.1696d Section 520.1696d... DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1696d Penicillin V tablets. (a) Specifications. Each tablet contains penicillin V potassium equivalent to 125 milligrams...

  10. 21 CFR 526.1696a - Penicillin G procaine.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Penicillin G procaine. 526.1696a Section 526.1696a... DRUGS, FEEDS, AND RELATED PRODUCTS INTRAMAMMARY DOSAGE FORM NEW ANIMAL DRUGS § 526.1696a Penicillin G procaine. (a) Specifications. Each 10-milliliter single-dose syringe contains penicillin G...

  11. Depletion of penicillin G residues in sows after intramuscular injection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The US-FDA CVM has not established a tolerance for penicillin residues in swine tissues, but across much of Europe and Asia a tolerance of 50 ppb penicillin G is in effect. In the US, heavy sows are often treated with extra-label doses of penicillin G, however appropriate pre-slaughter withdrawal p...

  12. 21 CFR 520.1696c - Penicillin V powder.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Penicillin V powder. 520.1696c Section 520.1696c... DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1696c Penicillin V powder. (a) Specifications. When reconstituted, each milliliter contains 25 milligrams (40,000 units) of penicillin V....

  13. 21 CFR 520.1696b - Penicillin G powder.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Penicillin G powder. 520.1696b Section 520.1696b... DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1696b Penicillin G powder. (a) Specifications. Each gram of powder contains penicillin G potassium equivalent to 1.54 million units...

  14. 21 CFR 520.1696c - Penicillin V powder.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Penicillin V powder. 520.1696c Section 520.1696c... DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1696c Penicillin V powder. (a) Specifications. When reconstituted, each milliliter contains 25 milligrams (40,000 units) of penicillin V....

  15. 21 CFR 520.1696b - Penicillin G powder.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Penicillin G powder. 520.1696b Section 520.1696b... DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1696b Penicillin G powder. (a) Specifications. Each gram of powder contains penicillin G potassium equivalent to 1.54 million units...

  16. 21 CFR 526.1696a - Penicillin G procaine.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Penicillin G procaine. 526.1696a Section 526.1696a... DRUGS, FEEDS, AND RELATED PRODUCTS INTRAMAMMARY DOSAGE FORM NEW ANIMAL DRUGS § 526.1696a Penicillin G procaine. (a) Specifications. Each 10-milliliter single-dose syringe contains penicillin G...

  17. 21 CFR 526.1696a - Penicillin G procaine.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Penicillin G procaine. 526.1696a Section 526.1696a... DRUGS, FEEDS, AND RELATED PRODUCTS INTRAMAMMARY DOSAGE FORM NEW ANIMAL DRUGS § 526.1696a Penicillin G procaine. (a) Specifications. Each 10-milliliter single-dose syringe contains penicillin G...

  18. Comparative study of 6-APA production by free and agar immobilized bacteria in nutrient broth culture.

    PubMed

    Dolui, A K; Das, S

    2011-04-01

    In the present study different bacterial samples were isolated from soil of different places of Dibrugarh and screened for biotransformation ability to produce 6-Aminopenicillanic acid. Among ten isolated bacterial samples, three gram positive bacterial samples designated as AKDD-2, AKDD-4 and AKDD-6 showed the production of 6-APA from penicillin G. Assessment of production of 6-APA after incubation in penicillin G (2 mg/ml) by three different samples separately in free and agar immobilization state was done by HPLC analysis. Reusability of immobilized cells was found successful up to 14 days. PMID:21614893

  19. Comparative study of 6-APA production by free and agar immobilized bacteria in nutrient broth culture.

    PubMed

    Dolui, A K; Das, S

    2011-04-01

    In the present study different bacterial samples were isolated from soil of different places of Dibrugarh and screened for biotransformation ability to produce 6-Aminopenicillanic acid. Among ten isolated bacterial samples, three gram positive bacterial samples designated as AKDD-2, AKDD-4 and AKDD-6 showed the production of 6-APA from penicillin G. Assessment of production of 6-APA after incubation in penicillin G (2 mg/ml) by three different samples separately in free and agar immobilization state was done by HPLC analysis. Reusability of immobilized cells was found successful up to 14 days.

  20. Characterization of an Enterococcus hirae penicillin-binding protein 3 with low penicillin affinity.

    PubMed

    Piras, G; el Kharroubi, A; van Beeumen, J; Coeme, E; Coyette, J; Ghuysen, J M

    1990-12-01

    Enterococcus hirae S185, a clinical isolate from swine intestine, exhibits a relatively high resistance to penicillin and contains two 77-kDa penicillin-binding proteins 3 of high (PBP 3s) and low (PBP 3r) affinity to penicillin, respectively. A laboratory mutant S185r has been obtained which overproduces PBP 3r and has a highly increased resistance to penicillin. Peptide fragments specifically produced by trypsin and SV8 protease digestions of PBP 3r were isolated, and the amino acid sequences of their amino terminal regions were determined. On the basis of these sequences, oligonucleotides were synthesized and used as primers to generate, by polymerization chain reaction, a 233-bp DNA fragment the sequence of which translated into a 73-amino-acid peptide segment of PBP 3r. These structural data led to the conclusion that the E. hirae PBP 3r and the methicillin-resistant staphylococcal PBP 2' are members of the same class of high-Mr PBPs. As shown by immunological tests, PBP 3r is not related to PBP 3s but, in contrast, is related to the 71-kDa PBP 5 of low penicillin affinity which is responsible for penicillin resistance in E. hirae ATCC 9790 and R40. PMID:2254261

  1. Regulation of penicillin biosynthesis in filamentous fungi.

    PubMed

    Brakhage, Axel A; Spröte, Petra; Al-Abdallah, Qusai; Gehrke, Alexander; Plattner, Hans; Tüncher, André

    2004-01-01

    The beta-lactam antibiotic penicillin is one of the mainly used antibiotics for the therapy of infectious diseases. It is produced as end product by some filamentous fungi only, most notably by Aspergillus (Emericella) nidulans and Penicillium chrysogenum. The penicillin biosynthesis is catalysed by three enzymes which are encoded by the following three genes: acvA (pcbAB), ipnA (pcbC) and aatA (penDE). The genes are organised into a gene cluster. Although the production of secondary metabolites as penicillin is not essential for the direct survival of the producing organisms, several studies indicated that the penicillin biosynthesis genes are controlled by a complex regulatory network, e.g. by the ambient pH, carbon source, amino acids, nitrogen etc. A comparison with the regulatory mechanisms (regulatory proteins and DNA elements) involved in the regulation of genes of primary metabolism in lower eukaryotes is thus of great interest. This has already led to the elucidation of new regulatory mechanisms. Positively acting regulators have been identified such as the pH dependent transcriptional regulator PACC, the CCAAT-binding complex AnCF and seem also to be represented by recessive trans-acting mutations of A. nidulans (prgA1, prgB1, npeE1) and R chrysogenum (carried by mutants Npe2 and Npe3). In addition, repressors like AnBH1 and VeA are involved in the regulation. Furthermore, such investigations have contributed to the elucidation of signals leading to the production of penicillin and can be expected to have a major impact on rational strain improvement programs.

  2. Penicillin inhibitors of purple acid phosphatase.

    PubMed

    Faridoon; Hussein, Waleed M; Ul Islam, Nazar; Guddat, Luke W; Schenk, Gerhard; McGeary, Ross P

    2012-04-01

    Purple acid phosphatases (PAPs) are binuclear metallohydrolases that have a multitude of biological functions and are found in fungi, bacteria, plants and animals. In mammals, PAP activity is linked with bone resorption and over-expression can lead to bone disorders such as osteoporosis. PAP is therefore an attractive target for the development of drugs to treat this disease. A series of penicillin conjugates, in which 6-aminopenicillanic acid was acylated with aromatic acid chlorides, has been prepared and assayed against pig PAP. The binding mode of most of these conjugates is purely competitive, and some members of this class have potencies comparable to the best PAP inhibitors yet reported. The structurally related penicillin G was shown to be neither an inhibitor nor a substrate for pig PAP. Molecular modelling has been used to examine the binding modes of these compounds in the active site of the enzyme and to rationalise their activities.

  3. Penicillin: its discovery and early development.

    PubMed

    Ligon, B Lee

    2004-01-01

    In August 1928, Alexander Fleming returned from a vacation to his usually messy, disordered laboratory. In one of the Petri dishes that had not been touched by the Lysol, he noticed an unusual phenomenon: separate colonies of staphylococci and, near the dish's edge, a colony of mold approximately 20 mm in diameter. The finding proved to be a watershed in the history of medicine. This discovery lay dormant for some time before other researchers took up the challenge to investigate its clinical possibilities. Two investigators at Oxford, Sir Howard Walter Florey and Ernst Boris Chain, brought penicillin's potential for medical use to fruition and, along with Fleming, shared the 1945 Nobel Prize for Medicine. The discovery and development of penicillin represent one of the most important developments in the annals of medical history. This article presents a brief overview of the events that occurred in the progress from discovery to implementation as a therapeutic agent. PMID:15175995

  4. Penicillin: its discovery and early development.

    PubMed

    Ligon, B Lee

    2004-01-01

    In August 1928, Alexander Fleming returned from a vacation to his usually messy, disordered laboratory. In one of the Petri dishes that had not been touched by the Lysol, he noticed an unusual phenomenon: separate colonies of staphylococci and, near the dish's edge, a colony of mold approximately 20 mm in diameter. The finding proved to be a watershed in the history of medicine. This discovery lay dormant for some time before other researchers took up the challenge to investigate its clinical possibilities. Two investigators at Oxford, Sir Howard Walter Florey and Ernst Boris Chain, brought penicillin's potential for medical use to fruition and, along with Fleming, shared the 1945 Nobel Prize for Medicine. The discovery and development of penicillin represent one of the most important developments in the annals of medical history. This article presents a brief overview of the events that occurred in the progress from discovery to implementation as a therapeutic agent.

  5. [Determination of penicillin intermediate and three penicillins in milk by high performance capillary electrophoresis].

    PubMed

    Tian, Chunqiu; Tan, Huarong; Gao, Liping; Shen, Huqin; Qi, Kezong

    2011-11-01

    A high performance capillary electrophoresis (HPCE) method was developed for the simultaneous determination of penicillin intermediate and penicillins in milk, including 6-amino-penicillanic acid (6-APA), penicillin G (PEN), ampicillin (AMP) and amoxicillin (AMO). The main parameters including the ion concentration and pH value of running buffer, separation voltage and column temperature were optimized systematically by orthogonal test. The four penicillins (PENs) were baseline separated within 4.5 min with the running buffer of 40 mmol/L potassium dihydrogen phosphate-20 mmol/L borax solution (pH 7.8), separation voltage of 28 kV and column temperature of 30 degrees C. The calibration curves showed good linearity in the range of 1.56 - 100 mg/L, and the correlation coefficients (r2) were between 0.9979 and 0.9998. The average recoveries at three spiked levels were in the range of 84.91% - 96.72% with acceptable relative standard deviations (RSDs) of 1.11% - 9.11%. The method is simple, fast, accurate and suitable for the determination of penicillins in real samples.

  6. Interference of Quorum Sensing by Delftia sp. VM4 Depends on the Activity of a Novel N-Acylhomoserine Lactone-Acylase

    PubMed Central

    Maisuria, Vimal B.; Nerurkar, Anuradha S.

    2015-01-01

    Background Turf soil bacterial isolate Delftia sp. VM4 can degrade exogenous N-acyl homoserine lactone (AHL), hence it effectively attenuates the virulence of bacterial soft rot pathogen Pectobacterium carotovorum subsp. carotovorum strain BR1 (Pcc BR1) as a consequence of quorum sensing inhibition. Methodology/Principal Findings Isolated Delftia sp. VM4 can grow in minimal medium supplemented with AHL as a sole source of carbon and energy. It also possesses the ability to degrade various AHL molecules in a short time interval. Delftia sp. VM4 suppresses AHL accumulation and the production of virulence determinant enzymes by Pcc BR1 without interference of the growth during co-culture cultivation. The quorum quenching activity was lost after the treatment with trypsin and proteinase K. The protein with quorum quenching activity was purified by three step process. Matrix assisted laser desorption/ionization-time of flight (MALDI-TOF) and Mass spectrometry (MS/MS) analysis revealed that the AHL degrading enzyme (82 kDa) demonstrates homology with the NCBI database hypothetical protein (Daci_4366) of D. acidovorans SPH-1. The purified AHL acylase of Delftia sp. VM4 demonstrated optimum activity at 20–40°C and pH 6.2 as well as AHL acylase type mode of action. It possesses similarity with an α/β-hydrolase fold protein, which makes it unique among the known AHL acylases with domains of the N-terminal nucleophile (Ntn)-hydrolase superfamily. In addition, the kinetic and thermodynamic parameters for hydrolysis of the different AHL substrates by purified AHL-acylase were estimated. Here we present the studies that investigate the mode of action and kinetics of AHL-degradation by purified AHL acylase from Delftia sp. VM4. Significance We characterized an AHL-inactivating enzyme from Delftia sp. VM4, identified as AHL acylase showing distinctive similarity with α/β-hydrolase fold protein, described its biochemical and thermodynamic properties for the first time and

  7. Penicillin and beta-lactam allergy: epidemiology and diagnosis.

    PubMed

    Macy, Eric

    2014-11-01

    Penicillin is the most common beta-lactam antibiotic allergy and the most common drug class allergy, reported in about 8% of individuals using health care in the USA. Only about 1% of individuals using health care in the USA have a cephalosporin allergy noted in their medical record, and other specific non-penicillin, non-cephalosporin beta-lactam allergies are even rarer. Most reported penicillin allergy is not associated with clinically significant IgE-mediated reactions after penicillin rechallenge. Un-verified penicillin allergy is a significant and growing public health problem. Clinically significant IgE-mediated penicillin allergy can be safely confirmed or refuted using skin testing with penicilloyl-poly-lysine and native penicillin G and, if skin test is negative, an oral amoxicillin challenge. Acute tolerance of an oral therapeutic dose of a penicillin class antibiotic is the current gold standard test for a lack of clinically significant IgE-mediated penicillin allergy. Cephalosporins and other non-penicillin beta-lactams are widely, safely, and appropriately used in individuals, even with confirmed penicillin allergy. There is little, if any, clinically significant immunologic cross-reactivity between penicillins and other beta-lactams. Routine cephalosporin skin testing should be restricted to research settings. It is rarely needed clinically to safely manage patients and has unclear predictive value at this time. The use of alternative cephalosporins, with different side chains, is acceptable in the setting of a specific cephalosporin allergy. Carbapenems and monobactams are also safely used in individuals with confirmed penicillin allergy. A certain predictable, but low, rate of adverse reactions will occur with all beta-lactam antibiotic use both pre- and post-beta-lactam allergy evaluations.

  8. Chemical reactions involved in penicillin allergy: kinetics and mechanism of penicillin aminolysis.

    PubMed

    Tsuji, A; Yamana, T; Miyamoto, E; Kiya, E

    1975-08-01

    In view of the fundamental importance of the reaction of penicillins with amino groups of proteins to the penicillin allergy, the aminolysis of benzylpenicillin by various amines was kinetically investigated. The formation rate constants, kamide, of benzylpenicilloylamides were determined at 35 degrees, 45 degrees and 60 degrees (mu equals 0.5), and found to obey the general rate law: kamide equals k1[amine] + k2[amine H+] [amine] + k3[amine]2 + k4[amine]aoh. All of the amines exhibited the unassisted nucleophilic rate constant, k1. The relative importance of the other kinetic terms depends on the basicity and the chemical structure of amines. The reaction mechanism of penicillin aminolysis was discussed. Bronsted relations for k1, k2 and k3, except for hydrazines, were satisfactory.

  9. The yellow brick road to penicillin: a story of serendipity.

    PubMed

    Henderson, J W

    1997-07-01

    Approximately 14 years elapsed between Sir Alexander Fleming's discovery of penicillin (in 1928) and its full-scale production for therapeutic use (in 1942) in World War II. The following factors were responsible for the delay: a scientific explanation of Fleming's "phenomenon," classification of the fungus secreting the active substance, source of the mold, initial difficulty of other bacteriologists in reproducing Fleming's discovery, identifying the chemical makeup of penicillin, search for other penicillin-producing organisms to enhance production of penicillin, purification and crystallization of penicillin, experiments on animals (chiefly mice) to determine toxicity, hesitancy to administer the drug to humans, standardization of an effective dosage for humans, and search for equipment and financial resources to enhance full-scale production. The adjunctive role of serendipity (chance, happenstance, improbability, and luck) in overcoming these obstacles and in contributing to the successful, scientific conclusion of the penicillin project is an unusual story.

  10. Site-directed mutagenesis and molecular modelling studies show the role of Asp82 and cysteines in rat acylase 1, a member of the M20 family

    SciTech Connect

    Herga, Sameh; Brutus, Alexandre; Vitale, Rosa Maria; Miche, Helene; Perrier, Josette; Puigserver, Antoine; Scaloni, Andrea; Giardina, Thierry . E-mail: thierry.giardina@univ.u-3mrs.fr

    2005-05-06

    Acylase 1 from rat kidney catalyzes the hydrolysis of acyl-amino acids. Sequence alignment has shown that this enzyme belongs to the metalloprotein family M20. Site-directed mutagenesis experiments led to the identification of one functionally important amino acid residue located near one of the zinc coordinating residues, which play a critical role in the enzymatic activity. The D82N- and D82E-substituted forms showed no significant activity and very low activity, respectively, along with a loss of zinc coordination. Molecular modelling investigations indicated a putative role of D82 in ensuring a proper protonation of catalytic histidine. In addition, none of the five cysteine residues present in the rat kidney acylase 1 sequence seemed involved in the catalytic process: the loss of activity induced by the C294A substitution was probably due to a conformational change in the 3D structure.

  11. Potential Cross-Reactivity Between Penicillin Derivatives and Cephalosporins.

    PubMed

    Putland, Stacey J; Soulsby, Natalie R; Ward, Sue M; Alderman, Christopher P

    2015-12-01

    Allergic reactions to both penicillins and cephalosporins are relatively common. Patients who have had a previous allergic reaction to a penicillin derivative may also be prone to a further reaction if treated with cephalosporins. This case illustrates several important points about potential cross-reactivity between penicillin derivatives and cephalosporins, as well as the benefits of an extended-hours pharmacy service in a longterm care facility.

  12. INCREASING AND PROLONGING BLOOD PENICILLIN CONCENTRATIONS FOLLOWING INTRAMUSCULAR ADMINISTRATION.

    PubMed

    Bronfenbrenner, J; Favour, C B

    1945-06-29

    (1) Restriction of fluid intake to 1,500 cc and the salt intake to 3 gm a day doubles the penicillin blood level following interrupted intramuscular [See Figure in the PDF file] injections of penicillin. (2) The administration of benzoic acid to a patient on an unrestricted diet Ilay double the penicillin blood level during similar treatment. (3) The combination of these two procedures results in a four- to eight-fold increase in penicillin blood level with a prolonged effective blood concentration.

  13. Cloning and nucleotide sequencing of a novel 7 beta-(4-carboxybutanamido)cephalosporanic acid acylase gene of Bacillus laterosporus and its expression in Escherichia coli and Bacillus subtilis.

    PubMed

    Aramori, I; Fukagawa, M; Tsumura, M; Iwami, M; Ono, H; Kojo, H; Kohsaka, M; Ueda, Y; Imanaka, H

    1991-12-01

    A strain of Bacillus species which produced an enzyme named glutaryl 7-ACA acylase which converts 7 beta-(4-carboxybutanamido)cephalosporanic acid (glutaryl 7-ACA) to 7-amino cephalosporanic acid (7-ACA) was isolated from soil. The gene for the glutaryl 7-ACA acylase was cloned with pHSG298 in Escherichia coli JM109, and the nucleotide sequence was determined by the M13 dideoxy chain termination method. The DNA sequence revealed only one large open reading frame composed of 1,902 bp corresponding to 634 amino acid residues. The deduced amino acid sequence contained a potential signal sequence in its amino-terminal region. Expression of the gene for glutaryl 7-ACA acylase was performed in both E. coli and Bacillus subtilis. The enzyme preparations purified from either recombinant strain of E. coli or B. subtilis were shown to be identical with each other as regards the profile of sodium dodecyl sulfate-polyacrylamide gel electrophoresis and were composed of a single peptide with the molecular size of 70 kDa. Determination of the amino-terminal sequence of the two enzyme preparations revealed that both amino-terminal sequences (the first nine amino acids) were identical and completely coincided with residues 28 to 36 of the open reading frame. Extracellular excretion of the enzyme was observed in a recombinant strain of B. subtilis. PMID:1744041

  14. Comparative activity in vitro of 16 antimicrobial agents against penicillin-susceptible meningococci and meningococci with diminished susceptibility to penicillin.

    PubMed Central

    Pérez Trallero, E; Garcia Arenzana, J M; Ayestaran, I; Muñoz Baroja, I

    1989-01-01

    Broad-spectrum cephalosporins were very active against strains of Neisseria meningitidis with both penicillin susceptibility and diminished penicillin susceptibility. Ceftriaxone was the most active antibiotic. Increases in MIC for 90% of meningococci with diminished susceptibility to penicillin of greater than or equal to 16-fold were observed for amdinocillin, cefuroxime, aztreonam, and imipenem; 2-fold increases were observed for ceftazidime, mezlocillin, and piperacillin. No differences were observed for non-beta-lactam antibiotics. PMID:2510596

  15. Design of penicillin fermentation process simulation system

    NASA Astrophysics Data System (ADS)

    Qi, Xiaoyu; Yuan, Zhonghu; Qi, Xiaoxuan; Zhang, Wenqi

    2011-10-01

    Real-time monitoring for batch process attracts increasing attention. It can ensure safety and provide products with consistent quality. The design of simulation system of batch process fault diagnosis is of great significance. In this paper, penicillin fermentation, a typical non-linear, dynamic, multi-stage batch production process, is taken as the research object. A visual human-machine interactive simulation software system based on Windows operation system is developed. The simulation system can provide an effective platform for the research of batch process fault diagnosis.

  16. Anaphylactic shock following oral penicillin--report of two cases.

    PubMed

    Myre, S; Zaske, D

    1976-03-01

    Two cases of anaphylactic shock secondary to oral penicillin therapy are presented. The clinical course and treatment of the two patients are discussed. Ways in which physicians and pharmacists may reduce the incidence and severity of anaphylactic reactions to penicillin are reviewed. PMID:1258884

  17. 21 CFR 520.1696 - Penicillin oral dosage forms.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Penicillin oral dosage forms. 520.1696 Section 520.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1696 Penicillin...

  18. 21 CFR 526.1696 - Penicillin intramammary dosage forms.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Penicillin intramammary dosage forms. 526.1696 Section 526.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Penicillin intramammary dosage forms....

  19. Depletion of penicillin G residues in sows after intramuscular injection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In 2011, the Food Safety Inspection Service (FSIS) switched from using the Fast Antimicrobial Screen Test (FAST) for screening animal tissues for penicillin to using the Charm-Kidney Inhibition Swab test (KIS). The switch provided a quicker test and lower detection limits for penicillin when used o...

  20. Penicillin: the medicine with the greatest impact on therapeutic outcomes.

    PubMed

    Kardos, Nelson; Demain, Arnold L

    2011-11-01

    The principal point of this paper is that the discovery of penicillin and the development of the supporting technologies in microbiology and chemical engineering leading to its commercial scale production represent it as the medicine with the greatest impact on therapeutic outcomes. Our nomination of penicillin for the top therapeutic molecule rests on two lines of evidence concerning the impact of this event: (1) the magnitude of the therapeutic outcomes resulting from the clinical application of penicillin and the subsequent widespread use of antibiotics and (2) the technologies developed for production of penicillin, including both microbial strain selection and improvement plus chemical engineering methods responsible for successful submerged fermentation production. These became the basis for production of all subsequent antibiotics in use today. These same technologies became the model for the development and production of new types of bioproducts (i.e., anticancer agents, monoclonal antibodies, and industrial enzymes). The clinical impact of penicillin was large and immediate. By ushering in the widespread clinical use of antibiotics, penicillin was responsible for enabling the control of many infectious diseases that had previously burdened mankind, with subsequent impact on global population demographics. Moreover, the large cumulative public effect of the many new antibiotics and new bioproducts that were developed and commercialized on the basis of the science and technology after penicillin demonstrates that penicillin had the greatest therapeutic impact event of all times.

  1. 21 CFR 520.1696 - Penicillin oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Penicillin oral dosage forms. 520.1696 Section 520.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1696 Penicillin...

  2. 21 CFR 520.1696 - Penicillin oral dosage forms.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Penicillin oral dosage forms. 520.1696 Section 520.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1696 Penicillin...

  3. 21 CFR 526.1696 - Penicillin intramammary dosage forms.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Penicillin intramammary dosage forms. 526.1696 Section 526.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Penicillin intramammary dosage forms....

  4. 21 CFR 526.1696 - Penicillin intramammary dosage forms.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Penicillin intramammary dosage forms. 526.1696 Section 526.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Penicillin intramammary dosage forms....

  5. 21 CFR 526.1696 - Penicillin intramammary dosage forms.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Penicillin intramammary dosage forms. 526.1696 Section 526.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Penicillin intramammary dosage forms....

  6. Penicillin Hydrolysis: A Kinetic Study of a Multistep, Multiproduct Reaction.

    ERIC Educational Resources Information Center

    McCarrick, Thomas A.; McLafferty, Fred W.

    1984-01-01

    Background, procedures used, and typical results are provided for an experiment in which students carry out the necessary measurements on the acid-catalysis of penicillin in two hours. By applying kinetic theory to the data obtained, the reaction pathways for the hydrolysis of potassium benzyl penicillin are elucidated. (JN)

  7. 21 CFR 558.155 - Chlortetracycline, sulfathiazole, penicillin.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    .... (a) Approvals. Type A medicated articles: (1) 20 grams of chlortetracycline hydrochloride, 4.4 percent (20 grams) sulfathiazole, and procaine penicillin equivalent to 10 grams of penicillin per pound to No. 046573 in § 510.600(c) of this chapter. (2) 40 grams of chlortetracycline hydrochloride,...

  8. Howard Florey, Alexander Fleming and the fairy tale of penicillin.

    PubMed

    Goldsworthy, Peter D; McFarlane, Alexander C

    2002-02-18

    The public myth of the discovery of penicillin is an archetypal "quest story" of the type common to every human culture. But the real story of the discovery, testing and refinement of penicillin is a complex tale of accident, serendipity, oversight, conflict, the pressure of war, idiosyncratic personalities and even--the invention of history.

  9. Does this child really have a penicillin allergy?

    PubMed

    Murphy, K; Scanlan, B; Coghlan, D

    2015-04-01

    Penicillins, the most prescribed paediatric medications worldwide, are also the most commonly reported cause of medication allergy, although this is rarely confirmed. An oral penicillin challenge is considered the gold standard in assessing children with suspected allergy but is seldom performed due to lack of appropriately trained staff and insufficient facilities. We introduced a standardised nurse-led protocol to evaluate children with suspected penicillin allergy fulfilling low risk criteria. In total, 40 children participated, including 22 girls and 18 boys, of which 38 met study criteria. There were 36 (95%) negative challenges completed, allowing these children to be safely prescribed oral penicillin in the future. There were 2 (5%) positive challenges developing similar signs to their initial reaction. This standardised protocol appears to be safe for use and efficient in the evaluation of low risk children with suspected penicillin allergy.

  10. Penicillin skin testing: potential implications for antimicrobial stewardship.

    PubMed

    Unger, Nathan R; Gauthier, Timothy P; Cheung, Linda W

    2013-08-01

    As the progression of multidrug-resistant organisms and lack of novel antibiotics move us closer toward a potential postantibiotic era, it is paramount to preserve the longevity of current therapeutic agents. Moreover, novel interventions for antimicrobial stewardship programs are integral to combating antimicrobial resistance worldwide. One unique method that may decrease the use of second-line antibiotics (e.g., fluoroquinolones, vancomycin) while facilitating access to a preferred β-lactam regimen in numerous health care settings is a penicillin skin test. Provided that up to 10% of patients have a reported penicillin allergy, of whom ~10% have true IgE-mediated hypersensitivity, significant potential exists to utilize a penicillin skin test to safely identify those who may receive penicillin or a β-lactam antibiotic. In this article, we provide information on the background, associated costs, currently available literature, pharmacists' role, antimicrobial stewardship implications, potential barriers, and misconceptions, as well as future directions associated with the penicillin skin test.

  11. Microalgal immobilization methods.

    PubMed

    Moreno-Garrido, Ignacio

    2013-01-01

    In this review, methods for the most common microalgal immobilization procedures are gathered and described. Passive (due to natural adherence of cells to surfaces) and active immobilization methods should be distinguished. Among active immobilization methods, calcium alginate entrapment is the most widely used method if living cells are intended to be immobilized, due to the chemical, optical, and mechanical characteristics of this substance. Immobilization in synthetic foams, immobilization in agar and carrageenan as well as immobilization in silica-based matrix or filters are also discussed and described. Finally, some considerations on the use of flocculation for microalgae are mentioned.

  12. Penicillin-binding site on the Escherichia coli cell envelope

    SciTech Connect

    Amaral, L.; Lee, Y.; Schwarz, U.; Lorian, V.

    1986-08-01

    The binding of /sup 35/S-labeled penicillin to distinct penicillin-binding proteins (PBPs) of the cell envelope obtained from the sonication of Escherichia coli was studied at different pHs ranging from 4 to 11. Experiments distinguishing the effect of pH on penicillin binding by PBP 5/6 from its effect on beta-lactamase activity indicated that although substantial binding occurred at the lowest pH, the amount of binding increased with pH, reaching a maximum at pH 10. Based on earlier studies, it is proposed that the binding at high pH involves the formation of a covalent bond between the C-7 of penicillin and free epsilon amino groups of the PBPs. At pHs ranging from 4 to 8, position 1 of penicillin, occupied by sulfur, is considered to be the site that establishes a covalent bond with the sulfhydryl groups of PBP 5. The use of specific blockers of free epsilon amino groups or sulfhydryl groups indicated that wherever the presence of each had little or no effect on the binding of penicillin by PBP 5, the presence of both completely prevented binding. The specific blocker of the hydroxyl group of serine did not affect the binding of penicillin.

  13. Proteome Analysis of the Penicillin Producer Penicillium chrysogenum

    PubMed Central

    Jami, Mohammad-Saeid; Barreiro, Carlos; García-Estrada, Carlos; Martín, Juan-Francisco

    2010-01-01

    Proteomics is a powerful tool to understand the molecular mechanisms causing the production of high penicillin titers by industrial strains of the filamentous fungus Penicillium chrysogenum as the result of strain improvement programs. Penicillin biosynthesis is an excellent model system for many other bioactive microbial metabolites. The recent publication of the P. chrysogenum genome has established the basis to understand the molecular processes underlying penicillin overproduction. We report here the proteome reference map of P. chrysogenum Wisconsin 54-1255 (the genome project reference strain) together with an in-depth study of the changes produced in three different strains of this filamentous fungus during industrial strain improvement. Two-dimensional gel electrophoresis, peptide mass fingerprinting, and tandem mass spectrometry were used for protein identification. Around 1000 spots were visualized by “blue silver” colloidal Coomassie staining in a non-linear pI range from 3 to 10 with high resolution, which allowed the identification of 950 proteins (549 different proteins and isoforms). Comparison among the cytosolic proteomes of the wild-type NRRL 1951, Wisconsin 54-1255 (an improved, moderate penicillin producer), and AS-P-78 (a penicillin high producer) strains indicated that global metabolic reorganizations occurred during the strain improvement program. The main changes observed in the high producer strains were increases of cysteine biosynthesis (a penicillin precursor), enzymes of the pentose phosphate pathway, and stress response proteins together with a reduction in virulence and in the biosynthesis of other secondary metabolites different from penicillin (pigments and isoflavonoids). In the wild-type strain, we identified enzymes to utilize cellulose, sorbitol, and other carbon sources that have been lost in the high penicillin producer strains. Changes in the levels of a few specific proteins correlated well with the improved penicillin

  14. [Quantitative determination of penicillins by iodometry using potassium hydrogen peroxymonosulfate].

    PubMed

    Blazhevskiĭ, N E; Karpova, S P; Kabachyĭ, V I

    2013-01-01

    The kinetics and stoichiometry of S-oxidation of semisynthetic penicillins (amoxicillin trihydrate, ampicillin trihydrate, sodium salt of oxacillin and ticarcillin disodium salt) by potassium hydrogen peroxymonosulfate in aqueous solutions at pH 3-6 was studied by iodometric titration: 1 mol of KNSO5 per 1 mol of penicillin, the quantitative interaction is achieved in 1 min (time of observation). A unified method was developed and the possibility of quantification of penicillins by the iodometric method using potassium hydrogen peroxymonosulfate as an analytical reagent was shown.

  15. 21 CFR 522.1696b - Penicillin G procaine aqueous suspension.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Penicillin G procaine aqueous suspension. 522... ANIMAL DRUGS § 522.1696b Penicillin G procaine aqueous suspension. (a) Specifications. Each milliliter contains penicillin G procaine equivalent to 300,000 units of penicillin G. (b) Sponsors. See...

  16. 21 CFR 522.1696c - Penicillin G procaine in oil.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Penicillin G procaine in oil. 522.1696c Section... § 522.1696c Penicillin G procaine in oil. (a) Specifications. Each milliliter contains penicillin G procaine equivalent to 300,000 units of penicillin G. (b) Sponsor. See No. 054771 in § 510.600(c) of...

  17. 21 CFR 522.1696c - Penicillin G procaine in oil.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Penicillin G procaine in oil. 522.1696c Section... § 522.1696c Penicillin G procaine in oil. (a) Specifications. Each milliliter contains penicillin G procaine equivalent to 300,000 units of penicillin G. (b) Sponsor. See No. 053501 in § 510.600(c) of...

  18. 21 CFR 522.1696b - Penicillin G procaine aqueous suspension.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Penicillin G procaine aqueous suspension. 522... ANIMAL DRUGS § 522.1696b Penicillin G procaine aqueous suspension. (a) Specifications. Each milliliter contains penicillin G procaine equivalent to 300,000 units of penicillin G. (b) Sponsors. See...

  19. 21 CFR 522.1696b - Penicillin G procaine aqueous suspension.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Penicillin G procaine aqueous suspension. 522... ANIMAL DRUGS § 522.1696b Penicillin G procaine aqueous suspension. (a) Specifications. Each milliliter contains penicillin G procaine equivalent to 300,000 units of penicillin G. (b) Sponsors. See...

  20. 21 CFR 522.1696c - Penicillin G procaine in oil.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Penicillin G procaine in oil. 522.1696c Section... § 522.1696c Penicillin G procaine in oil. (a) Specifications. Each milliliter contains penicillin G procaine equivalent to 300,000 units of penicillin G. (b) Sponsor. See No. 053501 in § 510.600(c) of...

  1. 21 CFR 522.1696b - Penicillin G procaine aqueous suspension.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Penicillin G procaine aqueous suspension. 522... ANIMAL DRUGS § 522.1696b Penicillin G procaine aqueous suspension. (a) Specifications. Each milliliter contains penicillin G procaine equivalent to 300,000 units of penicillin G. (b) Sponsors. See...

  2. 21 CFR 522.1696b - Penicillin G procaine aqueous suspension.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Penicillin G procaine aqueous suspension. 522... ANIMAL DRUGS § 522.1696b Penicillin G procaine aqueous suspension. (a) Specifications. Each milliliter contains penicillin G procaine equivalent to 300,000 units of penicillin G. (b) Sponsors. See...

  3. Osmotic Pressure, Bacterial Cell Walls, and Penicillin: A Demonstration.

    ERIC Educational Resources Information Center

    Lennox, John E.

    1984-01-01

    An easily constructed apparatus that models the effect of penicillin on the structure of bacterial cells is described. Background information and procedures for using the apparatus during a classroom demonstration are included. (JN)

  4. Industrial design of enzymic processes catalysed by very active immobilized derivatives: utilization of diffusional limitations (gradients of pH) as a profitable tool in enzyme engineering.

    PubMed

    Guisán, J M; Alvaro, G; Rosell, C M; Fernandez-Lafuente, R

    1994-12-01

    We have developed integrated studies of enzyme reaction engineering for the hydrolysis of penicillin G catalysed by very active penicillin G acylase (PGA) derivatives. We have studied the distinct effect of a key variable (pH) on different industrial parameters (e.g. activity/stability parameters). In this way we have demonstrated, in contrast with that proposed by other authors, that the generation of gradients of pH inside the porous structure of very active enzyme derivatives may be not a problem but a 'very profitable tool' to improve the whole set of industrial parameters. In this way we can establish two distinct 'optimal pH values': (i) the one inside the particle of the biocatalyst and (ii) the one in the bulk solution. The use of an external pH of 8.0 associated with the promotion of a controlled decrease in internal pH (e.g. around a mean value of 5.5) was very useful to simultaneously obtain interesting values of all industrial parameters: (i) very high hydrolytic yields (higher than 97%); (ii) a very important increase on the stability of PGA derivatives (higher than a 50-fold factor); and (iii) a very small decrease in operational activity (approximately 15%) as compared with the one of soluble enzyme at pH 8.0 with no diffusional hindrances.

  5. Seasonal Variation in Penicillin Susceptibility and Invasive Pneumococcal Disease

    PubMed Central

    Tam, Pui-Ying Iroh; Madoff, Lawrence C.; O'Connell, Michael; Pelton, Stephen I.

    2014-01-01

    We evaluated prospectively laboratory surveillance data from Massachusetts to investigate whether seasonal variation in invasive pneumococcal disease is associated with the proportion of penicillin susceptible isolates. The proportion of penicillin susceptible isolates associated with invasive pneumococcal disease varied by season, with proportions highest in the winter and lowest in the summer, and rates of invasive disease were highest in the autumn and winter seasons and lowest in the summer. PMID:25379834

  6. Why did the Fleming strain fail in penicillin industry?

    PubMed

    Rodríguez-Sáiz, Marta; Díez, Bruno; Barredo, José Luis

    2005-05-01

    Penicillin, discovered 75 years ago by Sir Alexander Fleming in Penicillium notatum, laid the foundations of modern antibiotic chemotherapy. Early work was carried out on the original Fleming strain, but it was later replaced by overproducing strains of Penicillium chrysogenum, which became the industrial penicillin producers. We show how a C(1357)-->T (A394V) change in the gene encoding PahA in P. chrysogenum may help to explain the drawback of P. notatum. PahA is a cytochrome P450 enzyme involved in the catabolism of phenylacetic acid (PA; a precursor of penicillin G). We expressed the pahA gene from P. notatum in P. chrysogenum obtaining transformants able to metabolize PA (P. chrysogenum does not), and observing penicillin production levels about fivefold lower than that of the parental strain. Our data thus show that a loss of function in P. chrysogenum PahA is directly related to penicillin overproduction, and support the historic choice of P. chrysogenum as the industrial producer of penicillin.

  7. Kinetic study of serum penicillin concentrations after single doses of benzathine and benethamine penicillins in young and old people.

    PubMed Central

    Collart, P; Poitevin, M; Milovanovic, A; Herlin, A; Durel, J

    1980-01-01

    In a comparative kinetic study of the serum concentrations of two penicillin complexes--medium-long-acting (benethamine penicillin) and long-acting (benzathine bipenicillin)--after a single injection in young adults and elderly people, the following results were confirmed statistically: (a) age was a major factor in the variations in serum penicillin concentrations and in their persistence in the serum; (b) the penicillin was absorbed faster in young than in elderly subjects even when a long-acting complex was used; (c) serum concentrations below the level regarded as lethal for treponemes appeared much earlier and more frequently in young than in old people; and (d) the bioequivalence between penicillin preparations could not be estimated solely for the number of units of the agent used but from the bioavailability of the chosen formulation. Thus a uniform and standard penicillin dosage allowing no safety margin may help in the superficial healing of a syphilitic chancre or the resolution of a roseola but it will certainly be insufficient to kill Treponema pallidum. It seems essential therefore to provide an antibiotic cover at high dosage over a long period of time. PMID:7448577

  8. Inactivation of penicillin G in milk using hydrogen peroxide.

    PubMed

    Hanway, W H; Hansen, A P; Anderson, K L; Lyman, R L; Rushing, J E

    2005-02-01

    Milk antibiotic residues have been a public concern in recent years. The Grade A Pasteurized Milk Ordinance mandates that raw Grade A milk will test negative for beta-lactam antibiotic residues before processing. The purpose of this research was to investigate the ability of various levels of peroxide and heat to inactivate penicillin G in raw milk. Whole milk spiked to a mean of 436 +/- 15.1 (standard error of the mean) ppb of potassium penicillin G was treated with hydrogen peroxide at levels of 0.0, 0.09, 0.17, and 0.34%. Samples at each peroxide level (n = 6 per treatment) were treated as follows: 1) incubated at 54.4 degrees C for 3 h, 2) pasteurized at 62.8 degrees C for 30 min, 3) incubated and pasteurized as in treatments 1 and 2, or 4) received no further treatment. A beta-lactam competitive microbial receptor assay was used for quantification of penicillin G. Concentrations of penicillin in selected samples were determined by HPLC for a comparison of test methods. Treatments were evaluated relative to their ability to reduce milk penicillin G levels to below the safe level of 5 ppb. The 0.09% hydrogen peroxide level was ineffective for all treatments. Hydrogen peroxide at 0.17% lowered the mean penicillin G (+/- SEM) from 436 +/- 15.1 to 6 +/- 1.49 ppb using the incubated and pasteurized heat treatment. The 0.34% concentration of hydrogen peroxide was the most effective, inactivating penicillin G to a level well below the safe level of 5 ppb with the pasteurized heat treatment, with or without incubation.

  9. AmiE, a Novel N-Acylhomoserine Lactone Acylase Belonging to the Amidase Family, from the Activated-Sludge Isolate Acinetobacter sp. Strain Ooi24

    PubMed Central

    Ochiai, Seiji; Yasumoto, Sera; Ikeda, Tsukasa

    2014-01-01

    Many Gram-negative bacteria use N-acyl-l-homoserine lactones (AHLs) as quorum-sensing signal molecules. We have reported that Acinetobacter strains isolated from activated sludge have AHL-degrading activity. In this study, we cloned the amiE gene as an AHL-degradative gene from the genomic library of Acinetobacter sp. strain Ooi24. High-performance liquid chromatography analysis revealed that AmiE functions as an AHL acylase, which hydrolyzes the amide bond of AHL. AmiE showed a high level of degrading activity against AHLs with long acyl chains but no activity against AHLs with acyl chains shorter than eight carbons. AmiE showed homology with a member of the amidases (EC 3.5.1.4) but not with any known AHL acylase enzymes. An amino acid sequence of AmiE from Ooi24 showed greater than 99% identities with uncharacterized proteins from Acinetobacter ursingii CIP 107286 and Acinetobacter sp. strain CIP 102129, but it was not found in the draft or complete genome sequences of other Acinetobacter strains. The presence of transposase-like genes around the amiE genes of these three Acinetobacter strains suggests that amiE is transferred by a putative transposon. Furthermore, the expression of AmiE in Pseudomonas aeruginosa PAO1 reduced AHL accumulation and elastase activity, which were regulated by AHL-mediated quorum sensing. PMID:25172868

  10. An engineered yeast efficiently secreting penicillin.

    PubMed

    Gidijala, Loknath; Kiel, Jan A K W; Douma, Rutger D; Seifar, Reza M; van Gulik, Walter M; Bovenberg, Roel A L; Veenhuis, Marten; van der Klei, Ida J

    2009-01-01

    This study aimed at developing an alternative host for the production of penicillin (PEN). As yet, the industrial production of this beta-lactam antibiotic is confined to the filamentous fungus Penicillium chrysogenum. As such, the yeast Hansenula polymorpha, a recognized producer of pharmaceuticals, represents an attractive alternative. Introduction of the P. chrysogenum gene encoding the non-ribosomal peptide synthetase (NRPS) delta-(L-alpha-aminoadipyl)-L-cysteinyl-D-valine synthetase (ACVS) in H. polymorpha, resulted in the production of active ACVS enzyme, when co-expressed with the Bacillus subtilis sfp gene encoding a phosphopantetheinyl transferase that activated ACVS. This represents the first example of the functional expression of a non-ribosomal peptide synthetase in yeast. Co-expression with the P. chrysogenum genes encoding the cytosolic enzyme isopenicillin N synthase as well as the two peroxisomal enzymes isopenicillin N acyl transferase (IAT) and phenylacetyl CoA ligase (PCL) resulted in production of biologically active PEN, which was efficiently secreted. The amount of secreted PEN was similar to that produced by the original P. chrysogenum NRRL1951 strain (approx. 1 mg/L). PEN production was decreased over two-fold in a yeast strain lacking peroxisomes, indicating that the peroxisomal localization of IAT and PCL is important for efficient PEN production. The breakthroughs of this work enable exploration of new yeast-based cell factories for the production of (novel) beta-lactam antibiotics as well as other natural and semi-synthetic peptides (e.g. immunosuppressive and cytostatic agents), whose production involves NRPS's. PMID:20016817

  11. An Engineered Yeast Efficiently Secreting Penicillin

    PubMed Central

    Gidijala, Loknath; Kiel, Jan A. K. W.; Douma, Rutger D.; Seifar, Reza M.; van Gulik, Walter M.; Bovenberg, Roel A. L.; Veenhuis, Marten; van der Klei, Ida J.

    2009-01-01

    This study aimed at developing an alternative host for the production of penicillin (PEN). As yet, the industrial production of this β-lactam antibiotic is confined to the filamentous fungus Penicillium chrysogenum. As such, the yeast Hansenula polymorpha, a recognized producer of pharmaceuticals, represents an attractive alternative. Introduction of the P. chrysogenum gene encoding the non-ribosomal peptide synthetase (NRPS) δ-(L-α-aminoadipyl)-L-cysteinyl-D-valine synthetase (ACVS) in H. polymorpha, resulted in the production of active ACVS enzyme, when co-expressed with the Bacillus subtilis sfp gene encoding a phosphopantetheinyl transferase that activated ACVS. This represents the first example of the functional expression of a non-ribosomal peptide synthetase in yeast. Co-expression with the P. chrysogenum genes encoding the cytosolic enzyme isopenicillin N synthase as well as the two peroxisomal enzymes isopenicillin N acyl transferase (IAT) and phenylacetyl CoA ligase (PCL) resulted in production of biologically active PEN, which was efficiently secreted. The amount of secreted PEN was similar to that produced by the original P. chrysogenum NRRL1951 strain (approx. 1 mg/L). PEN production was decreased over two-fold in a yeast strain lacking peroxisomes, indicating that the peroxisomal localization of IAT and PCL is important for efficient PEN production. The breakthroughs of this work enable exploration of new yeast-based cell factories for the production of (novel) β-lactam antibiotics as well as other natural and semi-synthetic peptides (e.g. immunosuppressive and cytostatic agents), whose production involves NRPS's. PMID:20016817

  12. Development of a penicillin biosensor using a single optical imaging fiber

    NASA Astrophysics Data System (ADS)

    Healey, Brian G.; Walt, David R.

    1995-05-01

    A penicillin biosensor has been fabricated by photodepositing penicillin-sensitive polymer matrices and pH-sensitive polymer matrices on different regions of an optical imaging fiber. Penicillin is detected by coupling the enzymatic activity of penicillinase with the pH sensitivity of fluorescein. Penicillin concentration is correlated to the pH change in the microenvironment of the penicillin-sensitive matrix relative to the pH of the sample solution. This dual sensor removes the need to maintain a constant solution pH when measuring penicillin and should enhance greatly the application of biosensors.

  13. Electronic structure and physicochemical properties of selected penicillins

    NASA Astrophysics Data System (ADS)

    Soriano-Correa, Catalina; Ruiz, Juan F. Sánchez; Raya, A.; Esquivel, Rodolfo O.

    Traditionally, penicillins have been used as antibacterial agents due to their characteristics and widespread applications with few collateral effects, which have motivated several theoretical and experimental studies. Despite the latter, their mechanism of biological action has not been completely elucidated. We present a theoretical study at the Hartree-Fock and density functional theory (DFT) levels of theory of a selected group of penicillins such as the penicillin-G, amoxicillin, ampicillin, dicloxacillin, and carbenicillin molecules, to systematically determine the electron structure of full ?-lactam antibiotics. Our results allow us to analyze the electronic properties of the pharmacophore group, the aminoacyl side-chain, and the influence of the substituents (R and X) attached to the aminoacyl side-chain at 6? (in contrast with previous studies focused at the 3? substituents), and to corroborate the results of previous studies performed at the semiempirical level, solely on the ?-lactam ring of penicillins. Besides, several density descriptors are determined with the purpose of analyzing their link to the antibacterial activity of these penicillin compounds. Our results for the atomic charges (fitted to the electrostatic potential), the bond orders, and several global reactivity descriptors, such as the dipole moments, ionization potential, hardness, and the electrophilicity index, led us to characterize: the active sites, the effect of the electron-attracting substituent properties and their physicochemical features, which altogether, might be important to understand the biological activity of these type of molecules.

  14. Documenting Penicillin Allergy: The Impact of Inconsistency

    PubMed Central

    Shah, Nirav S.; Ridgway, Jessica P.; Pettit, Natasha; Fahrenbach, John; Robicsek, Ari

    2016-01-01

    Background Allergy documentation is frequently inconsistent and incomplete. The impact of this variability on subsequent treatment is not well described. Objective To determine how allergy documentation affects subsequent antibiotic choice. Design Retrospective, cohort study. Participants 232,616 adult patients seen by 199 primary care providers (PCPs) between January 1, 2009 and January 1, 2014 at an academic medical system. Main Measures Inter-physician variation in beta-lactam allergy documentation; antibiotic treatment following beta-lactam allergy documentation. Key Results 15.6% of patients had a reported beta-lactam allergy. Of those patients, 39.8% had a specific allergen identified and 22.7% had allergic reaction characteristics documented. Variation between PCPs was greater than would be expected by chance (all p<0.001) in the percentage of their patients with a documented beta-lactam allergy (7.9% to 24.8%), identification of a specific allergen (e.g. amoxicillin as opposed to “penicillins”) (24.0% to 58.2%) and documentation of the reaction characteristics (5.4% to 51.9%). After beta-lactam allergy documentation, patients were less likely to receive penicillins (Relative Risk [RR] 0.16 [95% Confidence Interval: 0.15–0.17]) and cephalosporins (RR 0.28 [95% CI 0.27–0.30]) and more likely to receive fluoroquinolones (RR 1.5 [95% CI 1.5–1.6]), clindamycin (RR 3.8 [95% CI 3.6–4.0]) and vancomycin (RR 5.0 [95% CI 4.3–5.8]). Among patients with beta-lactam allergy, rechallenge was more likely when a specific allergen was identified (RR 1.6 [95% CI 1.5–1.8]) and when reaction characteristics were documented (RR 2.0 [95% CI 1.8–2.2]). Conclusions Provider documentation of beta-lactam allergy is highly variable, and details of the allergy are infrequently documented. Classification of a patient as beta-lactam allergic and incomplete documentation regarding the details of the allergy lead to beta-lactam avoidance and use of other antimicrobial

  15. Regulation and the circulation of knowledge: penicillin patents in Spain.

    PubMed

    Romero de Pablos, Ana

    2011-01-01

    This paper tells the early history of penicillin patenting in Spain. Patents turn out to be useful instruments for analysing the management of knowledge and its circulation in different professional and geographical domains. They protected knowledge while contributing to standardisation. Patents also ensured quality and guaranteed reliability in manufacturing, delivering and prescribing new drugs. They gained special prominence by allowing the creation of a network in which political, economic and business, industrial power, public health and international cooperation fields came together. The main source of information used for this purpose has been the earliest patent applications for penicillin in Spain between 1948 and 1950, which are kept in the Historical Archives of the Oficina Española de Patentes y Marcas. The study of these patents for penicillin shows their role as agents in introducing this drug in Spain. PMID:22332464

  16. Cloning, expression and purification of penicillin-binding protein 3 from Pseudomonas aeruginosa CMCC 10104.

    PubMed

    An, Yan Dong; Du, Qi Zhen; Tong, Li Yan; Yu, Zhao Wu; Gong, Xing Wen

    2015-06-01

    Penicillin-binding protein 3 (PBP3) of Pseudomonas aeruginosa is the primary target of β-lactams used to treat pseudomonas infections. Meanwhile, structure change and overproduction of PBP3 play important roles in the drug resistance of P. aeruginosa. Therefore, studies on the gene and structure of PBP3 are urgently needed. P. aeruginosa CMCC 10104 is a type culture strain common used in China. However, there is no report on its genomic and proteomic profiles. In this study, based on ftsI of P. aeruginosa PAO1, the gene encoding PBP3 was cloned from CMCC 10104. A truncated version of the ftsI gene, omitting the bases encoding the hydrophobic leader peptide (amino acids 1-34), was amplified by PCR. The cloned DNA shared 99.76% identity with ftsI from PAO1. Only four bases were different (66 C-A, 1020 T-C, 1233 T-C, and 1527 T-C). However, there were no differences between their deduced amino acid sequences. The recombinant PBP3 (rPBP3), containing a 6-histidine tag, was expressed in Escherichia coli BL21 (DE3). Immobilized metal affinity chromatography (IMAC) with Ni(2+)-NTA agarose was used for its purification. The purified rPBP3 was identified by SDS-PAGE and western blot analysis, and showed a single band at about 60kDa with purity higher than 95%. The penicillin-binding assay indicated that the obtained rPBP3 was functional and not hindered by the presence of the C-terminal His-tag. The protocol described in this study offers a method for obtaining purified recombinant PBP3 from P. aeruginosa CMCC 10104.

  17. Cloning, expression and purification of penicillin-binding protein 3 from Pseudomonas aeruginosa CMCC 10104.

    PubMed

    An, Yan Dong; Du, Qi Zhen; Tong, Li Yan; Yu, Zhao Wu; Gong, Xing Wen

    2015-06-01

    Penicillin-binding protein 3 (PBP3) of Pseudomonas aeruginosa is the primary target of β-lactams used to treat pseudomonas infections. Meanwhile, structure change and overproduction of PBP3 play important roles in the drug resistance of P. aeruginosa. Therefore, studies on the gene and structure of PBP3 are urgently needed. P. aeruginosa CMCC 10104 is a type culture strain common used in China. However, there is no report on its genomic and proteomic profiles. In this study, based on ftsI of P. aeruginosa PAO1, the gene encoding PBP3 was cloned from CMCC 10104. A truncated version of the ftsI gene, omitting the bases encoding the hydrophobic leader peptide (amino acids 1-34), was amplified by PCR. The cloned DNA shared 99.76% identity with ftsI from PAO1. Only four bases were different (66 C-A, 1020 T-C, 1233 T-C, and 1527 T-C). However, there were no differences between their deduced amino acid sequences. The recombinant PBP3 (rPBP3), containing a 6-histidine tag, was expressed in Escherichia coli BL21 (DE3). Immobilized metal affinity chromatography (IMAC) with Ni(2+)-NTA agarose was used for its purification. The purified rPBP3 was identified by SDS-PAGE and western blot analysis, and showed a single band at about 60kDa with purity higher than 95%. The penicillin-binding assay indicated that the obtained rPBP3 was functional and not hindered by the presence of the C-terminal His-tag. The protocol described in this study offers a method for obtaining purified recombinant PBP3 from P. aeruginosa CMCC 10104. PMID:25514204

  18. Sir Alexander Fleming: Scottish researcher who discovered penicillin.

    PubMed

    Ligon, B Lee

    2004-01-01

    The discovery and development of penicillin changed the entire direction of approaches to treating infectious diseases and saved the lives of millions of people. Indeed, the development of penicillin was a watershed event in the battle against infectious diseases, and the individual who discovered it, Sir Alexander Fleming, remains a prominent individual in the annals of medical history. This article focuses primarily on the personal life of Alexander Fleming, an individual who had a remarkable diversity of interests and who made many contributions to science and medicine.

  19. Catalytic activity of enzymes immobilized on AlGaN /GaN solution gate field-effect transistors

    NASA Astrophysics Data System (ADS)

    Baur, B.; Howgate, J.; von Ribbeck, H.-G.; Gawlina, Y.; Bandalo, V.; Steinhoff, G.; Stutzmann, M.; Eickhoff, M.

    2006-10-01

    Enzyme-modified field-effect transistors (EnFETs) were prepared by immobilization of penicillinase on AlGaN /GaN solution gate field-effect transistors. The influence of the immobilization process on enzyme functionality was analyzed by comparing covalent immobilization and physisorption. Covalent immobilization by Schiff base formation on GaN surfaces modified with an aminopropyltriethoxysilane monolayer exhibits high reproducibility with respect to the enzyme/substrate affinity. Reductive amination of the Schiff base bonds to secondary amines significantly increases the stability of the enzyme layer. Electronic characterization of the EnFET response to penicillin G indicates that covalent immobilization leads to the formation of an enzyme (sub)monolayer.

  20. 21 CFR 524.1484h - Neomycin, penicillin, polymyxin, hydrocortisone suspension.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Neomycin, penicillin, polymyxin, hydrocortisone... NEW ANIMAL DRUGS § 524.1484h Neomycin, penicillin, polymyxin, hydrocortisone suspension. (a... milligrams of neomycin, 10,000 international units of penicillin G procaine, 5,000 international units...

  1. 21 CFR 520.1696b - Penicillin G potassium in drinking water.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Penicillin G potassium in drinking water. 520....1696b Penicillin G potassium in drinking water. (a) Specifications. When reconstituted, each milliliter contains penicillin G potassium equivalent to 20,000, 25,000, 40,000, 50,000, 80,000, or 100,000 units...

  2. 21 CFR 520.1696b - Penicillin G potassium in drinking water.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Penicillin G potassium in drinking water. 520....1696b Penicillin G potassium in drinking water. (a) Specifications. When reconstituted, each milliliter contains penicillin G potassium equivalent to 20,000, 25,000, 40,000, 50,000, 80,000, or 100,000 units...

  3. 75 FR 55798 - North American Bioproducts Corporation; Filing of Food Additive Petition (Animal Use); Penicillin...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-14

    ... Additive Petition (Animal Use); Penicillin G Procaine AGENCY: Food and Drug Administration, HHS. ACTION... safe use of penicillin G procaine as an antimicrobial processing aid in fuel- ethanol fermentations... safe use of penicillin G procaine as an antimicrobial processing aid in fuel- ethanol...

  4. 21 CFR 524.1484h - Neomycin, penicillin, polymyxin, hydrocortisone suspension.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Neomycin, penicillin, polymyxin, hydrocortisone... NEW ANIMAL DRUGS § 524.1484h Neomycin, penicillin, polymyxin, hydrocortisone suspension. (a... milligrams of neomycin, 10,000 international units of penicillin G procaine, 5,000 international units...

  5. 21 CFR 520.1696c - Penicillin V potassium for oral solution.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Penicillin V potassium for oral solution. 520....1696c Penicillin V potassium for oral solution. (a) Specifications. When reconstituted, each milliliter contains 25 milligrams (40,000 units) of penicillin V. (b) Sponsor. See No. 050604 in § 510.600(c) of...

  6. 21 CFR 524.1484h - Neomycin, penicillin, polymyxin B, and hydrocortisone suspension.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Neomycin, penicillin, polymyxin B, and... DOSAGE FORM NEW ANIMAL DRUGS § 524.1484h Neomycin, penicillin, polymyxin B, and hydrocortisone suspension... equivalent to 17.5 milligrams of neomycin, 10,000 international units of penicillin G procaine,...

  7. 21 CFR 520.1696b - Penicillin G potassium in drinking water.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Penicillin G potassium in drinking water. 520....1696b Penicillin G potassium in drinking water. (a) Specifications. When reconstituted, each milliliter contains penicillin G potassium equivalent to 20,000, 25,000, 40,000, 50,000, 80,000, or 100,000 units...

  8. Penicillin amidohydrolase productivity of locally isolated bacterial species.

    PubMed

    Mahmood, Z A; Shaikh, D; Zoha, S M

    1991-01-01

    Penicillin amidohydrolase productivity of four locally isolated bacterial species is described. Organisms were identified as Escherichia coli, Pseudomonas aeruginosa, Sarcina lutea and Bacillus megaterium. Highest enzyme productivity of 3.2 U/mL with a corresponding dry cell mass of 4.5 g/L was recorded from S. lutea. PMID:1821869

  9. Management of allergy to penicillins and other beta-lactams.

    PubMed

    Mirakian, R; Leech, S C; Krishna, M T; Richter, A G; Huber, P A J; Farooque, S; Khan, N; Pirmohamed, M; Clark, A T; Nasser, S M

    2015-02-01

    The Standards of Care Committee of the British Society for Allergy and Clinical Immunology (BSACI) and an expert panel have prepared this guidance for the management of immediate and non-immediate allergic reactions to penicillins and other beta-lactams. The guideline is intended for UK specialists in both adult and paediatric allergy and for other clinicians practising allergy in secondary and tertiary care. The recommendations are evidence based, but where evidence is lacking, the panel reached consensus. During the development of the guideline, all BSACI members were consulted using a Web-based process and all comments carefully considered. Included in the guideline are epidemiology of allergic reactions to beta-lactams, molecular structure, formulations available in the UK and a description of known beta-lactam antigenic determinants. Sections on the value and limitations of clinical history, skin testing and laboratory investigations for both penicillins and cephalosporins are included. Cross-reactivity between penicillins and cephalosporins is discussed in detail. Recommendations on oral provocation and desensitization procedures have been made. Guidance for beta-lactam allergy in children is given in a separate section. An algorithm to help the clinician in the diagnosis of patients with a history of penicillin allergy has also been included.

  10. 21 CFR 526.1696 - Penicillin intramammary dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Penicillin intramammary dosage forms. 526.1696 Section 526.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS INTRAMAMMARY DOSAGE FORMS § 526.1696...

  11. 21 CFR 520.1696d - Penicillin V potassium tablets.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Penicillin V potassium tablets. 520.1696d Section 520.1696d Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Nos. 017144, 050604, and 053501 in § 510.600(c) of this chapter. (c) National Academy of...

  12. 21 CFR 520.1696d - Penicillin V potassium tablets.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Penicillin V potassium tablets. 520.1696d Section 520.1696d Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Nos. 017144, 050604, and 053501 in § 510.600(c) of this chapter. (c) National Academy of...

  13. Actinomycosis after allogeneic hematopoietic stem cell transplantation despite penicillin prophylaxis.

    PubMed

    Barraco, F; Labussière-Wallet, H; Valour, F; Ducastelle-Leprêtre, S; Nicolini, F-E; Thomas, X; Ferry, T; Dumitrescu, O; Michallet, M; Ader, F

    2016-08-01

    Actinomycosis is a rare chronic and multifaceted disease caused by Actinomyces species frequently mimicking malignancy or other chronic granulomatous lung diseases. We report 4 original presentations of actinomycosis arising under supposed penicillin prophylaxis in allogeneic stem cell transplantation recipients. PMID:27203624

  14. Evaluation of aerobic co-composting of penicillin fermentation fungi residue with pig manure on penicillin degradation, microbial population dynamics and composting maturity.

    PubMed

    Zhang, Zhenhua; Zhao, Juan; Yu, Cigang; Dong, Shanshan; Zhang, Dini; Yu, Ran; Wang, Changyong; Liu, Yan

    2015-12-01

    Improper treatment of penicillin fermentation fungi residue (PFFR), one of the by-products of penicillin production process, may result in environmental pollution due to the high concentration of penicillin. Aerobic co-composting of PFFR with pig manure was determined to degrade penicillin in PFFR. Results showed that co-composting of PFFR with pig manure can significantly reduce the concentration of penicillin in PFFR, make the PFFR-compost safer as organic fertilizer for soil application. More than 99% of penicillin in PFFR were removed after 7-day composting. PFFR did not affect the composting process and even promote the activity of the microorganisms in the compost. Quantitative PCR (qPCR) indicated that the bacteria and actinomycetes number in the AC samples were 40-80% higher than that in the pig-manure compost (CK) samples in the same composting phases. This research indicated that the aerobic co-composting was a feasible PFFR treatment method. PMID:26409851

  15. Overexpression of two penicillin structural genes in Aspergillus nidulans.

    PubMed

    Fernández-Cañón, J M; Peñalva, M A

    1995-01-01

    We have placed two different penicillin structural genes from Aspergillus nidulans, ipnA (encoding isopenicillin N synthetase, IPNS) and acyA (encoding acyl-CoA:6-aminopenicillanic acid acyltransferase, AAT), under the control of the strong alcA promoter [alcA(p)]. Single copies of these transcriptional fusions were targeted to the same chromosomal location and conditions have been worked out which simultaneously allow induction of the alcA(p) and support penicillin biosynthesis. Transcriptional induction of the chimeric genes alcA(p)::ipnA or alcA(p)::acyA(cdna) in the relevant recombinant strains results in 10-fold higher levels of the ipnA or acyA transcripts than those resulting from transcription of the corresponding endogenous genes. This increase causes a 40-fold rise in IPNS activity or a 8-fold rise in AAT activity. Despite this rise in enzyme levels, forced expression of the ipnA gene results in only a modest increase in levels of exported penicillin, whereas forced expression of the acyA gene reduces penicillin production, showing that neither of these enzymes is rate-limiting for penicillin biosynthesis in A. nidulans. A genomic version of the alcA(p)::acyA fusion in which the acyA gene is interrupted by three small introns, is inducible by threonine to a lesser extent (as determined by both acyA mRNA levels and AAT enzyme levels) than the corresponding cDNA version, suggesting that processing of the introns present in the primary transcript may limit acyA expression.

  16. Free radicals properties of gamma-irradiated penicillin-derived antibiotics: piperacillin, ampicillin, and crystalline penicillin.

    PubMed

    Wilczyński, Sławomir; Pilawa, Barbara; Koprowski, Robert; Wróbel, Zygmunt; Ptaszkiewicz, Marta; Swakoń, Jan; Olko, Paweł

    2014-03-01

    The aim of this work was to determine the concentrations and properties of free radicals in piperacillin, ampicillin, and crystalline penicillin after gamma irradiation. The radicals were studied by electron paramagnetic resonance (EPR) spectroscopy using an X-band spectrometer (9.3 GHz). Gamma irradiation was performed at a dose of 25 kGy. One- and two-exponential functions were fitted to the experimental data, in order to assess the influence of the antibiotics' storage time on the measured EPR lines. After gamma irradiation, complex EPR lines were recorded confirming the presence of a large number of free radicals formed during the irradiation. For all tested antibiotics, concentrations of free radicals and parameters of EPR spectra changed with storage time. The results obtained demonstrate that concentration of free radicals and other spectroscopic parameters can be used to select the optimal parameters of radiation sterilization of β-lactam antibiotics. The most important parameters are the constants τ (τ (1(A),(I)) and τ (2(A),(I))) and K (K (0(A),(I)), K (1(A),(I)), K (2(A),(I))) of the exponential functions that describe free radicals decay during samples storage.

  17. Involvement of Histamine and RhoA/ROCK in Penicillin Immediate Hypersensitivity Reactions.

    PubMed

    Han, Jiayin; Yi, Yan; Li, Chunying; Zhang, Yushi; Wang, Lianmei; Zhao, Yong; Pan, Chen; Liang, Aihua

    2016-01-01

    The mechanism of penicillin immediate hypersensitivity reactions has not been completely elucidated. These reactions are generally considered to be mediated by IgE, but penicillin-specific IgE could not be detected in most cases. This study demonstrated that penicillin was able to cause vascular hyperpermeability in a mouse model mimicking clinical symptoms of penicillin immediate hypersensitivity reactions. The first exposure to penicillin also induced immediate edema and exudative reactions in ears and lungs of mice in a dose-dependent manner. Vasodilation was noted in microvessels in ears. These reactions were unlikely to be immune-mediated reactions, because no penicillin-specific IgE was produced. Furthermore, penicillin treatment directly elicited rapid histamine release. Penicillin also led to F-actin reorganization in human umbilical vein endothelial cells and increased the permeability of the endothelial monolayer. Activation of the RhoA/ROCK signaling pathway was observed in ears and lungs of mice and in endothelial cells after treatment with penicillin. Both an anti-histamine agent and a ROCK inhibitor attenuated penicillin immediate hypersensitivity reactions in mice. This study presents a novel mechanism of penicillin immediate hypersensitivity reactions and suggests a potential preventive approach against these reactions. PMID:27619816

  18. Involvement of Histamine and RhoA/ROCK in Penicillin Immediate Hypersensitivity Reactions

    PubMed Central

    Han, Jiayin; Yi, Yan; Li, Chunying; Zhang, Yushi; Wang, Lianmei; Zhao, Yong; Pan, Chen; Liang, Aihua

    2016-01-01

    The mechanism of penicillin immediate hypersensitivity reactions has not been completely elucidated. These reactions are generally considered to be mediated by IgE, but penicillin-specific IgE could not be detected in most cases. This study demonstrated that penicillin was able to cause vascular hyperpermeability in a mouse model mimicking clinical symptoms of penicillin immediate hypersensitivity reactions. The first exposure to penicillin also induced immediate edema and exudative reactions in ears and lungs of mice in a dose-dependent manner. Vasodilation was noted in microvessels in ears. These reactions were unlikely to be immune-mediated reactions, because no penicillin-specific IgE was produced. Furthermore, penicillin treatment directly elicited rapid histamine release. Penicillin also led to F-actin reorganization in human umbilical vein endothelial cells and increased the permeability of the endothelial monolayer. Activation of the RhoA/ROCK signaling pathway was observed in ears and lungs of mice and in endothelial cells after treatment with penicillin. Both an anti-histamine agent and a ROCK inhibitor attenuated penicillin immediate hypersensitivity reactions in mice. This study presents a novel mechanism of penicillin immediate hypersensitivity reactions and suggests a potential preventive approach against these reactions. PMID:27619816

  19. 21 CFR 526.1696b - Penicillin G procaine-dihydrostreptomycin in soybean oil for intramammary infusion (dry cows).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Penicillin G procaine-dihydrostreptomycin in... INTRAMAMMARY DOSAGE FORM NEW ANIMAL DRUGS § 526.1696b Penicillin G procaine-dihydrostreptomycin in soybean oil... penicillin G procaine equivalent to 200,000 units of penicillin G and dihydrostreptomycin sulfate...

  20. 21 CFR 526.1696b - Penicillin G procaine-dihydrostreptomycin in soybean oil for intramammary infusion (dry cows).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Penicillin G procaine-dihydrostreptomycin in... INTRAMAMMARY DOSAGE FORM NEW ANIMAL DRUGS § 526.1696b Penicillin G procaine-dihydrostreptomycin in soybean oil... penicillin G procaine equivalent to 200,000 units of penicillin G and dihydrostreptomycin sulfate...

  1. 21 CFR 526.1696b - Penicillin G procaine-dihydrostreptomycin in soybean oil for intramammary infusion (dry cows).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Penicillin G procaine-dihydrostreptomycin in... INTRAMAMMARY DOSAGE FORM NEW ANIMAL DRUGS § 526.1696b Penicillin G procaine-dihydrostreptomycin in soybean oil... penicillin G procaine equivalent to 200,000 units of penicillin G and dihydrostreptomycin sulfate...

  2. 21 CFR 526.1696b - Penicillin G procaine-dihydrostreptomycin in soybean oil for intramammary infusion (dry cows).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Penicillin G procaine-dihydrostreptomycin in... INTRAMAMMARY DOSAGE FORM NEW ANIMAL DRUGS § 526.1696b Penicillin G procaine-dihydrostreptomycin in soybean oil... penicillin G procaine equivalent to 200,000 units of penicillin G and dihydrostreptomycin sulfate...

  3. Thermodynamics of Association of Structurally Related Amphiphilic Penicillins.

    PubMed

    Taboada; Attwood; García; Jones; Ruso; Mosquera; Sarmiento

    2000-01-15

    Critical micelle concentrations (CMCs) of the penicillins cloxacillin and dicloxacillin in water were determined by conductivity measurements over the temperature range 288.15 to 313.15 K. Both penicillins showed minimum CMCs at temperatures close to 298.15 K. Thermodynamic parameters of aggregate formation were derived from the variation of the CMC with temperature using a modified form of the mass action model applicable to systems of low aggregation number. Values for the enthalpy of aggregate formation, DeltaH(0)(m), calculated by this method showed that the aggregation of both cloxacillin and dicloxacillin became increasingly exothermic with increase in temperature. The predicted DeltaH(0)(m) at 298.15 K was in good agreement with the value determined experimentally by calorimetry for each drug. Copyright 2000 Academic Press.

  4. Merlin Pryce (1902-1976) and penicillin: an abiding mystery.

    PubMed

    Wyn Jones, Emyr; Wyn Jones, R Gareth

    2002-12-01

    In the scientific and medical pantheon few have received more adulation and honour than Sir Alexander Fleming. Even so it is abundantly clear that his triumphant discovery of penicillin owed much to the work of others, especially Florey and Chain, who accomplished the difficult task of taking penicillin from the test tube to patient. This essay does not attempt a detailed re-examination of that discovery. Rather the present study suggests that even the initial observation on that critical day in September 1928 and its subsequent ramifications were even more complex and perplexing than the accepted version. It is likely that Professor Daniel Merlin Pryce, a somewhat unconventional but gifted son of the Welsh mining valleys played an important, quite possibly a crucial, role in the original observation. However one which, except for a very few occasions, he himself sought to downplay, even virtually to deny.

  5. Plutonium Immobilization Puck Handling

    SciTech Connect

    Kriikku, E.

    1999-01-26

    The Plutonium Immobilization Project (PIP) will immobilize excess plutonium and store the plutonium in a high level waste radiation field. To accomplish these goals, the PIP will process various forms of plutonium into plutonium oxide, mix the oxide powder with ceramic precursors, press the mixture into pucks, sinter the pucks into a ceramic puck, load the pucks into metal cans, seal the cans, load the cans into magazines, and load the magazines into a Defense Waste Processing Facility (DPWF) canister. These canisters will be sent to the DWPF, an existing Savannah River Site (SRS) facility, where molten high level waste glass will be poured into the canisters encapsulating the ceramic pucks. Due to the plutonium radiation, remote equipment will perform these operations in a contained environment. The Plutonium Immobilization Project is in the early design stages and the facility will begin operation in 2005. This paper will discuss the Plutonium Immobilization puck handling conceptual design and the puck handling equipment testing.

  6. Development of immobilized cellulase

    SciTech Connect

    Luther, M.A.; Halbert, D.J.

    1982-08-01

    The immobilization of cellulase from the fungus Trichoderma reesei on the surface of calcium alginate gel spheres was investigated. The immobilized cellulase catalyzed the hydrolysis of cellulose to glucose. The linking agents, 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) and glutaraldehyde, decreased free-enzyme activity by 95%, and the maximum observed retention of cellulase activity after immobilization was 2%. Leakage of enzyme from the support was observed. A fivefold increase in glucose production was seen after the addition of ..beta..-glucosidase-impregnated spheres to the cellulase spheres, suggesting that cellobiose may be accumulating during the reaction. A simple economic analysis suggested that the immobilized-enzyme activity per unit volume might have to be increased by a factor of fifty to become competitive with the free-enzyme process.

  7. Immobilization induced hypercalcemia

    PubMed Central

    Cano-Torres, Edgar Alonso; González-Cantú, Arnulfo; Hinojosa-Garza, Gabriela; Castilleja-Leal, Fernando

    2016-01-01

    Summary Immobilization hypercalcemia is an uncommon diagnosis associated with increased bone remodeling disorders and conditions associated with limited movement such as medullar lesions or vascular events. Diagnosis requires an extensive evaluation to rule out other causes of hypercalcemia. This is a report of a woman with prolonged immobilization who presented with severe hypercalcemia. This case contributes to identification of severe hypercalcemia as a result of immobility and the description of bone metabolism during this state. PMID:27252745

  8. Effect of aeration rate on composting of penicillin mycelial dreg.

    PubMed

    Chen, Zhiqiang; Zhang, Shihua; Wen, Qinxue; Zheng, Jun

    2015-11-01

    Pilot scale experiments with forced aeration were conducted to estimate effects of aeration rates on the performance of composting penicillin mycelial dreg using sewage sludge as inoculation. Three aeration rates of 0.15, 0.50 and 0.90L/(min·kg) organic matter (OM) were examined. The principal physicochemical parameters were monitored during the 32day composting period. Results showed that the higher aeration rate of 0.90L/(min·kg) did not corresponded to a longer thermophilic duration and higher rates of OM degradation; but the lower aeration rate of 0.15L/(min·kg) did induce an accumulation of NH4(+)-N contents due to the inhibition of nitrification. On the other hand, aeration rate has little effect on degradation of penicillin. The results show that the longest phase of thermophilic temperatures≥55°C, the maximum NO3(-)-N content and seed germination, and the minimum C/N ratio were obtained with 0.50L/(min·kg) OM. Therefore, aeration rates of 0.50L/(min·kg) OM can be recommended for composting penicillin mycelial dreg.

  9. Effect of aeration rate on composting of penicillin mycelial dreg.

    PubMed

    Chen, Zhiqiang; Zhang, Shihua; Wen, Qinxue; Zheng, Jun

    2015-11-01

    Pilot scale experiments with forced aeration were conducted to estimate effects of aeration rates on the performance of composting penicillin mycelial dreg using sewage sludge as inoculation. Three aeration rates of 0.15, 0.50 and 0.90L/(min·kg) organic matter (OM) were examined. The principal physicochemical parameters were monitored during the 32day composting period. Results showed that the higher aeration rate of 0.90L/(min·kg) did not corresponded to a longer thermophilic duration and higher rates of OM degradation; but the lower aeration rate of 0.15L/(min·kg) did induce an accumulation of NH4(+)-N contents due to the inhibition of nitrification. On the other hand, aeration rate has little effect on degradation of penicillin. The results show that the longest phase of thermophilic temperatures≥55°C, the maximum NO3(-)-N content and seed germination, and the minimum C/N ratio were obtained with 0.50L/(min·kg) OM. Therefore, aeration rates of 0.50L/(min·kg) OM can be recommended for composting penicillin mycelial dreg. PMID:26574101

  10. A New Method to Determine the Half-Life for Penicillin Using Microcalorimeter

    NASA Astrophysics Data System (ADS)

    Li, Z. X.; Zhao, W. W.

    2015-01-01

    The dissolution process of penicillin in normal saline and isotonic glucose solution was reported using a microcalorimeter. Both the integral and differential heats of solution were measured. The quantitative relationships between the amount of heat released and the quantity of dissolved penicillin were established. Meanwhile, the kinetics and the half-life of the dissolution processes as well as the enthalpy of solution, the entropy of dissolution, and the free energy of dissolution were determined. The results showed that a change of the solvent from normal saline to isotonic glucose solution had little effect on the half-life of penicillin in the dissolution process, and there was no significant difference between the stabilities of penicillin in isotonic glucose solution and normal saline. Moreover, the dissolution process of penicillin in isotonic glucose solution followed the first-order kinetics. These results could provide a theoretical basis for the clinical applications of penicillin.

  11. Prevalence and characteristics of reported penicillin allergy in an urban outpatient adult population.

    PubMed

    Albin, Stephanie; Agarwal, Shradha

    2014-01-01

    Penicillin allergy remains the most common drug allergy, with a reported prevalence of 10% in the United States. Epidemiology of penicillin allergy in outpatient populations is relatively scarce. This study sought to determine the prevalence and characteristics of reported penicillin allergy in an urban outpatient population and to identify trends in clinical evaluation and management from a tertiary center serving a large inner-city population. A retrospective review of electronic medical records was performed of adult patients seen in the Internal Medicine Associates Clinic of Mount Sinai Hospital between January 31, 2012, and July 31, 2012. Medical records were selected based on the documentation of penicillin in patient's allergy section. Of the 11,761 patients seen in the clinic, 1348 patients (11.5%) reported a history of penicillin allergy. The most common allergic reactions were rash (37%), unknown/undocumented (20.2%), hives (18.9%), swelling/angioedema (11.8%), and anaphylaxis (6.8%). There was an increased prevalence of penicillin allergy in female patients compared with male patients (odds ratio [OR] = 1.82; 95% CI = 1.60, 2.08; p < 0.0001), and there were significantly fewer Asians with penicillin allergy compared with Caucasians (OR = 0.51; 95% CI = 0.32, 0.83; p = 0.007). However, only 78 (6%) of the patients reporting penicillin allergy had a referral to an allergy specialist. Overall, improved referral to an allergist will help to identify patients who have penicillin allergy requiring avoidance.

  12. In vitro activities of 22 beta-lactam antibiotics against penicillin-resistant and penicillin-susceptible viridans group streptococci isolated from blood.

    PubMed Central

    Alcaide, F; Liñares, J; Pallares, R; Carratala, J; Benitez, M A; Gudiol, F; Martin, R

    1995-01-01

    A total of 410 strains of viridans group streptococci isolated consecutively from blood were tested by the microdilution method for in vitro susceptibility to 22 beta-lactam antibiotics. One hundred thirty-eight strains (33.6%) were resistant to penicillin with a MIC range of 0.25 to 8 micrograms/ml. MICs of all beta-lactam agents tested were higher for penicillin-resistant strains than for susceptible strains. These antibiotics were classified into three groups according to their in vitro activities (MICs at which 50 and 90% of the isolates are inhibited). Beta-Lactams of the first group (these included imipenem, cefpirome, FK-037, cefditoren, cefotaxime, ceftriaxone, and cefepime) showed activities higher than or similar to that of penicillin against penicillin-resistant viridans group streptococci. However, 80% of highly penicillin-resistant Streptococcus mitis organisms required cefotaxime and ceftriaxone MICs of > or = 2 micrograms/ml (range, 2 to 16 micrograms/ml). Beta-Lactams of the second group (cefpodoxime, ampicillin, amoxicillin-clavulanate, piperacillin, and cefuroxime) showed lower activities than penicillin. Finally, antibiotics of the third group (cephalothin, oxacillin, ceftazidime, cefixime, cefaclor, cefetamet, cefadroxil, cephalexin, and ceftibuten) showed poor in vitro activities. Therefore, some of the beta-lactam agents included in the first group could be an acceptable alternative in the treatment of serious infections due to strains highly resistant to penicillin, although clinical experience is needed. PMID:8619576

  13. [The immobilization of giraffes].

    PubMed

    Wiesner, H; von Hegel, G

    1989-01-01

    The anatomical and physiological conditions of blood circulation in the giraffe are pointed out. 16 immobilizations in the giraffe of either sex are reported, of which 10 were immobilized according to the following scheme. 1. Premedication: 30 mg Xylazine 150 mg Hyaluronidase 2. 15 minutes later a halter with two long ropes is put on to hold up the animals' heads after they lay down. 3. 20 minutes after premedication the injection of 5.6-6.0 mg Etorphine (2.5-2.7 ml Immobilon) together with 150 I.U. Hyaluronidase follows. 4. We think that the most important fact is to hold the animals head and neck in an upright position during the whole time of immobilization. 5. Within 3 to 5 minutes after the intravenous application of 15 mg Diprenorphine (5.0 ml Revivon) the animals raise without any problems.

  14. Quantum chemical study of penicillin: Reactions after acylation

    NASA Astrophysics Data System (ADS)

    Li, Rui; Feng, Dacheng; Zhu, Feng

    The density functional theory methods were used on the model molecules of penicillin to determine the possible reactions after their acylation on ?-lactamase, and the results were compared with sulbactam we have studied. The results show that, the acylated-enzyme tetrahedral intermediate can evolves with opening of ?-lactam ring as well as the thiazole ring; the thiazole ring-open products may be formed via ?-lactam ring-open product or from tetrahedral intermediate directly. Those products, in imine or enamine form, can tautomerize via hydrogen migration. In virtue of the water-assisted, their energy barriers are obviously reduced.

  15. Novel penicillins synthesized by biotransformation using laccase from Trametes spec.

    PubMed

    Mikolasch, Annett; Niedermeyer, Timo Horst Johannes; Lalk, Michael; Witt, Sabine; Seefeldt, Simone; Hammer, Elke; Schauer, Frieder; Gesell, Manuela; Hessel, Susanne; Jülich, Wolf-Dieter; Lindequist, Ulrike

    2006-05-01

    Eight novel penicillins were synthesized by heteromolecular reaction of ampicillin or amoxicillin with 2,5-dihydroxybenzoic acid derivatives using a laccase from Trametes spec. All products inhibited the growth of several gram positive bacterial strains in the agar diffusion assay, among them methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococci. The products protected mice against an infection with Staphylococcus aureus lethal to the untreated animals. Cytotoxicity and acute toxicity of the new compounds were neglectable. The results show the usefulness of laccase for the synthesis of potential new antibiotics. The biological activity of the new compounds stimulates intensified pharmacological tests.

  16. Sub-inhibitory concentrations of penicillin G induce biofilm formation by field isolates of Actinobacillus pleuropneumoniae.

    PubMed

    Hathroubi, S; Fontaine-Gosselin, S-È; Tremblay, Y D N; Labrie, J; Jacques, M

    2015-09-30

    Actinobacillus pleuropneumoniae is a Gram-negative bacterium and causative agent of porcine pleuropneumonia. This is a highly contagious disease that causes important economic losses to the swine industry worldwide. Penicillins are extensively used in swine production and these antibiotics are associated with high systemic clearance and low oral bioavailability. This may expose A. pleuropneumoniae to sub-inhibitory concentrations of penicillin G when the antibiotic is administered orally. Our goal was to evaluate the effect of sub-minimum inhibitory concentration (MIC) of penicillin G on the biofilm formation of A. pleuropneumoniae. Biofilm production of 13 field isolates from serotypes 1, 5a, 7 and 15 was tested in the presence of sub-MIC of penicillin G using a polystyrene microtiter plate assay. Using microscopy techniques and enzymatic digestion, biofilm architecture and composition were also characterized after exposure to sub-MIC of penicillin G. Sub-MIC of penicillin G significantly induced biofilm formation of nine isolates. The penicillin G-induced biofilms contained more poly-N-acetyl-D-glucosamine (PGA), extracellular DNA and proteins when compared to control biofilms grown without penicillin G. Additionally, penicillin G-induced biofilms were sensitive to DNase which was not observed with the untreated controls. Furthermore, sub-MIC of penicillin G up-regulated the expression of pgaA, which encodes a protein involved in PGA synthesis, and the genes encoding the envelope-stress sensing two-component regulatory system CpxRA. In conclusion, sub-MICs of penicillin G significantly induce biofilm formation and this is likely the result of a cell envelope stress sensed by the CpxRA system resulting in an increased production of PGA and other matrix components.

  17. Physician approaches to beta-lactam use in patients with penicillin hypersensitivity.

    PubMed

    Prematta, Tracy; Shah, Shenil; Ishmael, Faoud T

    2012-01-01

    Beta-lactam antibiotics are widely used, but hypersensitivity reactions are common and difficult to manage. This study was designed to identify lack of knowledge regarding the safe use of alternative beta-lactams in penicillin-allergic patients and assess management differences between allergists and nonallergists. An electronic physician survey was sent to 623 providers in allergy, internal medicine, pediatrics, and family medicine, querying beta-lactam use in patients with a history of penicillin allergy. A total of 110 (17.7%) surveys were completed. For patients with a prior maculopapular rash to penicillin, most providers were uncomfortable prescribing penicillins again, although they would use other beta-lactams. In patients with an exfoliative dermatitis to penicillin, 46% of responders would not prescribe any beta-lactam again. For patients with a positive skin test to penicillin, only 45.1% of nonallergists were comfortable prescribing monobactams versus 62.5% of allergists; 30.3% of all responders would give a carbapenem. In patients with urticaria to penicillin, pediatricians were the most comfortable prescribing third- or fourth-generation cephalosporins. Providers (both allergists and nonallergists) were unfamiliar with the safety of prescribing penicillin in patients with history of maculopapular rash, the safety of monobactams, and low cross-reactivity with carbapenems in penicillin-allergic individuals. Nonallergists were also unfamiliar with the usefulness of penicillin skin testing. Improved education is needed to address these areas. Additionally, we found variability in responses regarding exfoliative dermatitis and comfort prescribing cephalosporins in patients with suspected IgE-mediated drug allergy to penicillin, highlighting the need for additional research in these areas.

  18. Penicillin-induced liver injury during treatment for ocular neurosyphilis.

    PubMed

    Wilkinson, Janelle; Zainal, Abir; Naqvi, Syed Yaseen

    2016-01-01

    A 51-year-old man, homosexual, recently diagnosed with ocular neurosyphilis, presented to the emergency room with a 1-day history of fevers and chills. His vital signs were significant for a temperature of 102.8°F and tachycardia of 125 bpm. The patient had experienced blurred vision in his left eye and was diagnosed with ocular neurosyphilis 10 days prior to the current presentation. He was treated with a 14-day course of high-dose intravenous penicillin and oral prednisone. His laboratory studies were significant for transaminitis, with an aspartate aminotransferase of 1826 U/L, alanine aminotransferase of 1743 U/L, total bilirubin of 1.2 mg/dL and alkaline phosphatase of 68 U/L. After ruling out viral aetiologies and toxin-induced hepatic injury, penicillin was discontinued on the day following admission and transaminases promptly improved with resolution of symptoms. The patient's vision returned to normal within 2 weeks after discharge from hospital. PMID:27389728

  19. Beta-lactamase gene expression in a penicillin-resistant Bacillus anthracis strain.

    PubMed

    Chen, Yahua; Tenover, Fred C; Koehler, Theresa M

    2004-12-01

    Expression of the bla1 and bla2 genes in an archetypal Bacillus anthracis strain is insufficient for penicillin resistance. In a penicillin-resistant clinical isolate, both genes are highly transcribed, but bla1 is the major contributor to high-level resistance to ampicillin. Differential expression of the bla genes is dependent upon strain background. PMID:15561870

  20. 21 CFR 522.1696 - Penicillin G procaine implantation and injectable dosage forms.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Penicillin G procaine implantation and injectable dosage forms. 522.1696 Section 522.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH... DOSAGE FORM NEW ANIMAL DRUGS § 522.1696 Penicillin G procaine implantation and injectable dosage forms....

  1. 21 CFR 522.1696 - Penicillin G procaine injectable dosage forms.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Penicillin G procaine injectable dosage forms. 522.1696 Section 522.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... ANIMAL DRUGS § 522.1696 Penicillin G procaine injectable dosage forms....

  2. 21 CFR 522.1696 - Penicillin G procaine implantation and injectable dosage forms.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Penicillin G procaine implantation and injectable dosage forms. 522.1696 Section 522.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH... DOSAGE FORM NEW ANIMAL DRUGS § 522.1696 Penicillin G procaine implantation and injectable dosage forms....

  3. Determination of penicillin G in heavy sow urine using immunochromatographic assay and microbial inhibition swab tests

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: Penicillin is a commonly used antibiotic in food animals. Unfortunately, violative penicillin residues in animal carcasses are sometimes identified by the USDA Food Safety and Inspection Service. Ante-mortem matrices such as urine could prove valuable for predicting possible violativ...

  4. 21 CFR 522.1696 - Penicillin G procaine implantation and injectable dosage forms.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Penicillin G procaine implantation and injectable dosage forms. 522.1696 Section 522.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH... DOSAGE FORM NEW ANIMAL DRUGS § 522.1696 Penicillin G procaine implantation and injectable dosage forms....

  5. 21 CFR 522.1696 - Penicillin G procaine implantation and injectable dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Penicillin G procaine implantation and injectable dosage forms. 522.1696 Section 522.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH... DOSAGE FORM NEW ANIMAL DRUGS § 522.1696 Penicillin G procaine implantation and injectable dosage forms....

  6. Myositis complicating benzathine penicillin-G injection in a case of rheumatic heart disease.

    PubMed

    Francis, Joshua R; Wyber, Rosemary; Remenyi, Bo; Croser, David; Carapetis, Jonathan

    2016-01-01

    A 7-year old boy developed myositis secondary to intramuscular injection of benzathine penicillin-G in the context of secondary prophylaxis for rheumatic heart disease. Side effects of intramuscular delivery of benzathine penicillin-G are well described and include injection site pain and inflammation, but myositis, as depicted on magnetic resonance imaging in this case, has not previously been described.

  7. Prevalence and genotyping of commensal Neisseria with reduced susceptibility to penicillin.

    PubMed

    Mechergui, Arij; Achour, Wafa; Ben Hassen, Assia

    2015-01-01

    We analyzed 85 Neisseria spp. strains collected by swabbing from neutropenic patients to determine the prevalence of reduced susceptibility to penicillin and to ascertain the clonal relationship between these strains. High genetic diversity and an elevated level of penicillin resistance were found among commensal Neisseria clinical isolates.

  8. Galvanostatic entrapment of penicillinase into polytyramine films and its utilization for the potentiometric determination of penicillin.

    PubMed

    Ismail, Fatma; Adeloju, Samuel B

    2010-01-01

    A sensitive and reliable potentiometric biosensor for determination of penicillin has been developed by exploiting the self-limiting growth of the non-conducting polymer, polytyramine. Optimum polytyramine-penicillinase (PTy-PNCnase) films for potentiometric detection of penicillin were accomplished with monomer solutions which contained 0.03 M tyramine, 37 U/mL penicillinase, 0.01 M KNO3, and 3 mM penicillin with an applied current density of 0.8 mA/cm2 and an electropolymerisation time of 40 seconds. The potentiometric biosensor gave a linear concentration range of 3-283 μM for penicillin and achieved a minimum detectable concentration of 0.3 μM. The biosensor was successfully utilized for the detection of Amoxycillin and gave an average percentage recovery of 102±6%. Satisfactory recoveries of penicillin G were also achieved in milk samples with the potentiometric biosensor when concentrations are ≥20 ppm.

  9. Synergy between baicalein and penicillins against penicillinase-producing Staphylococcus aureus.

    PubMed

    Qian, Minyi; Tang, Shusheng; Wu, Congming; Wang, Yang; He, Tao; Chen, Tingting; Xiao, Xilong

    2015-09-01

    The combination of baicalein (the active constituent of Scutellaria baicalensis) with penicillin G/amoxicillin showed potent synergy against 20 clinical penicillinase-producing Staphylococcus aureus strains including 10 isolates that were additionally methicillin-resistant (MRSA). The fractional inhibitory concentration (FIC) indices of penicillins+baiclein ranged from 0.14 to 0.38. Baicalein protected penicillins (penicillin G and amoxicillin) from penicillinase and increased the susceptibility of penicillinase-supplemented S. aureus ATCC 29213 in a dose-dependent manner. The inhibition of penicillinase activity by baicalein should be responsible for the synergism and protective effect. These findings offer us good evidence that the penicillins combined with baicalein showed potent synergistic activity against penicillinase-producing S. aureus and penicillinase-producing MRSA in vitro and might provide promising implications for clinical treatment of these bacterial infections.

  10. Penicillin decreases chloride conductance in crustacean muscle: a model for the epileptic neuron.

    PubMed

    Hochner, B; Spira, M E; Werman, R

    1976-04-30

    The effects of penicillin were studied on the neuromuscular preparation of the ghost crab, Ocypoda cursor. Penicillin in doses lower than 2 mM reduced both the amplitude of inhibitory junction potentials and conductance increases induced by external application of GABA. The nature of the latter effect appears to be 2-fold, a weaker competitive inhibition and a more powerful non-competitive effech which may be ionophore blockade. Penicillin in concentrations above 2 mM diminished resting conductance, especially that of chloride. The action of penicillin is, in general, to decrease chloride conductance in this preparation. The crustacean neuromuscular preparation may provide a useful analogue for understanding penicillin evoked epilepsy. The reduced chloride conductance could explain decreased inhibition, increased excitation and depolarization shifts in cortical neurons.

  11. Industrial use of immobilized enzymes.

    PubMed

    DiCosimo, Robert; McAuliffe, Joseph; Poulose, Ayrookaran J; Bohlmann, Gregory

    2013-08-01

    Although many methods for enzyme immobilization have been described in patents and publications, relatively few processes employing immobilized enzymes have been successfully commercialized. The cost of most industrial enzymes is often only a minor component in overall process economics, and in these instances, the additional costs associated with enzyme immobilization are often not justified. More commonly the benefit realized from enzyme immobilization relates to the process advantages that an immobilized catalyst offers, for example, enabling continuous production, improved stability and the absence of the biocatalyst in the product stream. The development and attributes of several established and emerging industrial applications for immobilized enzymes, including high-fructose corn syrup production, pectin hydrolysis, debittering of fruit juices, interesterification of food fats and oils, biodiesel production, and carbon dioxide capture are reviewed herein, highlighting factors that define the advantages of enzyme immobilization. PMID:23436023

  12. Industrial use of immobilized enzymes.

    PubMed

    DiCosimo, Robert; McAuliffe, Joseph; Poulose, Ayrookaran J; Bohlmann, Gregory

    2013-08-01

    Although many methods for enzyme immobilization have been described in patents and publications, relatively few processes employing immobilized enzymes have been successfully commercialized. The cost of most industrial enzymes is often only a minor component in overall process economics, and in these instances, the additional costs associated with enzyme immobilization are often not justified. More commonly the benefit realized from enzyme immobilization relates to the process advantages that an immobilized catalyst offers, for example, enabling continuous production, improved stability and the absence of the biocatalyst in the product stream. The development and attributes of several established and emerging industrial applications for immobilized enzymes, including high-fructose corn syrup production, pectin hydrolysis, debittering of fruit juices, interesterification of food fats and oils, biodiesel production, and carbon dioxide capture are reviewed herein, highlighting factors that define the advantages of enzyme immobilization.

  13. Synergy of Penicillin-Netilmicin Combinations Against Enterococci Including Strains Highly Resistant to Streptomycin or Kanamycin

    PubMed Central

    Sanders, Christine C.

    1977-01-01

    The in vitro activity of combinations of penicillin and netilimicin was determined against 20 clinical isolates of enterococci and compared with that obtained in simultaneous tests with penicillin/sisomicin, penicillin/streptomycin, and penicillin/kanamycin. Synergy between the two drugs in each combination was determined by the use of quantitative kill curves and was defined as a killing by the combination at least 100-fold greater than that produced by the most effective drug alone. Penicillin/netilmicin and penicillin/sisomicin combinations were found to be synergistic against the majority of isolates tested, including strains resistant to penicillin/streptomycin or penicillin/kanamycin combinations. This synergy with penicillin could be demonstrated at a concentration of ≤7 μg/ml for either netilmicin or sisomicin. Studies on the kinetics of killing produced by these combinations showed the rate and extent of killing to be directly dependent upon the organism's relative susceptibility to the aminoglycoside alone and the aminoglycoside concentration in the combination. Results also indicated that the interaction between penicillin and netilmicin was true synergy; i.e., rapid and complete killing was produced by combinations containing each drug at concentrations insufficient to produce any killing alone, and the killing observed could not be produced by either drug alone at a concentration equivalent to the total drug concentration in the combination. The potential clinical application of this synergistic interaction should be investigated further, especially in view of recent reports showing netilmicin to be considerably less toxic than gentamicin in experimental animals. PMID:242509

  14. Identification of a group of Haemophilus influenzae penicillin-binding proteins that may have complementary physiological roles

    SciTech Connect

    Malouin, F.; Parr, T.R. Jr.; Bryan, L.E. )

    1990-02-01

    (35S)penicillin bound to different Haemophilus influenzae proteins in assays performed at 20, 37, or 42{degrees}C. Penicillin-binding proteins 3a, 3b, 4, and 4' formed a group characterized by their affinity for moxalactam, cefotaxime, and piperacillin. Penicillin-binding protein 4' showed specific properties that may reflect its complementary role in septation.

  15. 21 CFR 526.1696c - Penicillin G procaine-dihydrostreptomycin sulfate for intramammary infusion (dry cows).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Penicillin G procaine-dihydrostreptomycin sulfate... INTRAMAMMARY DOSAGE FORM NEW ANIMAL DRUGS § 526.1696c Penicillin G procaine-dihydrostreptomycin sulfate for intramammary infusion (dry cows). (a) Specifications. Each 10 milliliters of suspension contains penicillin...

  16. 76 FR 14024 - Draft Guidance for Industry on Non-Penicillin Beta-Lactam Risk Assessment: A CGMP Framework...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-15

    ... HUMAN SERVICES Food and Drug Administration Draft Guidance for Industry on Non-Penicillin Beta-Lactam... guidance for industry entitled ``Non-Penicillin Beta-Lactam Risk Assessment: A CGMP Framework.'' This... non- penicillin beta-lactam antibiotics. The draft guidance is intended to assist manufacturers...

  17. 21 CFR 526.1696c - Penicillin G procaine-dihydrostreptomycin sulfate for intramammary infusion (dry cows).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Penicillin G procaine-dihydrostreptomycin sulfate... INTRAMAMMARY DOSAGE FORMS § 526.1696c Penicillin G procaine-dihydrostreptomycin sulfate for intramammary infusion (dry cows). (a) Specifications. Each 10 milliliters of suspension contains penicillin G...

  18. 21 CFR 526.1696c - Penicillin G procaine-dihydrostreptomycin sulfate for intramammary infusion (dry cows).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Penicillin G procaine-dihydrostreptomycin sulfate... INTRAMAMMARY DOSAGE FORM NEW ANIMAL DRUGS § 526.1696c Penicillin G procaine-dihydrostreptomycin sulfate for intramammary infusion (dry cows). (a) Specifications. Each 10 milliliters of suspension contains penicillin...

  19. 21 CFR 526.1696c - Penicillin G procaine-dihydrostreptomycin sulfate for intramammary infusion (dry cows).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Penicillin G procaine-dihydrostreptomycin sulfate... INTRAMAMMARY DOSAGE FORM NEW ANIMAL DRUGS § 526.1696c Penicillin G procaine-dihydrostreptomycin sulfate for intramammary infusion (dry cows). (a) Specifications. Each 10 milliliters of suspension contains penicillin...

  20. 21 CFR 526.1696c - Penicillin G procaine-dihydrostreptomycin sulfate for intramammary infusion (dry cows).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Penicillin G procaine-dihydrostreptomycin sulfate... INTRAMAMMARY DOSAGE FORM NEW ANIMAL DRUGS § 526.1696c Penicillin G procaine-dihydrostreptomycin sulfate for intramammary infusion (dry cows). (a) Specifications. Each 10 milliliters of suspension contains penicillin...

  1. 21 CFR 526.1696b - Penicillin G procaine-dihydrostreptomycin in soybean oil for intramammary infusion (dry cows).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Penicillin G procaine-dihydrostreptomycin in... INTRAMAMMARY DOSAGE FORMS § 526.1696b Penicillin G procaine-dihydrostreptomycin in soybean oil for intramammary infusion (dry cows). (a) Specifications. Each 10 milliliters of suspension contains penicillin G...

  2. Bacteriostatic polymer film immobilization.

    PubMed

    El-Hayek, Rami F; Dye, Kevin; Warner, John C

    2006-12-15

    Coatings of quaternary ammonium tertiary structures (QUATS) copolymerized with 4-vinylbenzylthymine (VBT) exhibited high antimicrobial activity against Escherichia coli. Immobilization of QUATS improves environmental performance by preventing release of antibacterials to the environment, helping to preclude the emergence of resistant strains. The crosslinking immobilization scheme reported herein provides a more environmentally benign and more inexpensive synthesis than previously reported, thus reducing the use of solvents, energy, and production time. Development of water soluble, thymine-based photopolymers was inspired by the UV-induced 2pi + 2pi photocyclodimerization of thymine in DNA. Copolymers of 4-vinylbenzylthymine and trimethylammonium chloride, triethylammonium chloride, or dimethyloctylammonium chloride were synthesized in different monomer ratios. The antibacterial properties were tested by coating VBT:QUATS in sterilized petri dishes, crosslinking under short UV light, spraying with aqueous suspensions of bacterial cells, air drying, and then applying agar media to promote bacterial growth. The plates were incubated for 24 h at 37 degrees C. The number of viable cells ranged from 17 to 0% growth. Immobilized VBT:QUAT copolymers are antiseptic surfaces that can be produced in an environmentally benign fashion.

  3. Purification of penicillin-binding protein 2 of Escherichia coli.

    PubMed Central

    Curtis, S J; Strominger, J L

    1981-01-01

    Penicillin-binding protein 2 (PBP-2) of Escherichia coli K-12 was purified by covalent affinity chromatography using 6-aminopenicillanic acid covalently coupled to carboxymethyl-Sepharose (6-APA-CM-Sepharose). Purification of PBP-2 was accomplished by prebinding the methoxy cephalosporin, cefoxitin, to the Triton X-100-solubilized PBPs of E. coli and then incubating the PBPs with 6-APA-CM-Sepharose. Cefoxitin readily binds to all the E. coli PBPs except PBP-2 and, thus, in the presence of cefoxitin, only PBP-2 could bind to the 6-APA-CM-Sepharose. The purification of a mixture of all of the PBPs of E. coli by affinity chromatography is also described. Images PMID:7007320

  4. Evaluating effects of penicillin treatment on the metabolome of rats.

    PubMed

    Sun, Jinchun; Schnackenberg, Laura K; Khare, Sangeeta; Yang, Xi; Greenhaw, James; Salminen, William; Mendrick, Donna L; Beger, Richard D

    2013-08-01

    Penicillin (PEN) V, a well-known antibiotic widely used in the treatment of Gram-positive bacterial infections, was evaluated in this study. LC/MS- and NMR-based metabolic profiling were employed to examine the effects of PEN on the host's metabolic phenotype. Male Sprague Dawley rats were randomly divided into groups that were orally administered either 0.5% methylcellulose vehicle, 100 or 2400mg PEN/kg body weight once daily for up to 14 consecutive days. Urine, plasma and tissue were collected from groups sacrificed at 6h, 24h or 14d. The body fluids were subjected to clinical chemistry and metabolomics analysis; the tissue samples were processed for histopathology. The only notable clinical chemistry observation was that gamma glutamyltransferase (GGT) significantly decreased at 24h for both dose groups, and significantly decreased at 14d for the high-dose groups. Partial least squares discriminant analysis scores plots of the metabolomics data from urine and plasma samples showed dose- and time-dependent grouping patterns. Time- and dose-dependent decreases in urinary metabolites including indole-containing metabolites (such as 3-methyldioxyindole sulfate generated from bacterial metabolism of tryptophan), organic acids containing phenyl groups (such as hippuric acid, phenyllactic acid and 3-hydroxyanthranilic acid), and metabolites conjugated with sulfate or glucuronide (such as cresol sulfate and aminophenol sulfate) indicated that the gut microflora population was suppressed. Decreases in many host-gut microbiota urinary co-metabolites (indole- and phenyl-containing metabolites, amino acids, vitamins, nucleotides and bile acids) suggested gut microbiota play important roles in the regulation of host metabolism, including dietary nutrient absorption and reprocessing the absorbed nutrients. Decreases in urinary conjugated metabolites (sulfate, glucuronide and glycine conjugates) implied that gut microbiota might have an impact on chemical detoxification

  5. Impact of penicillin nonsusceptibility on clinical outcomes of patients with nonmeningeal Streptococcus pneumoniae bacteremia in the era of the 2008 clinical and laboratory standards institute penicillin breakpoints.

    PubMed

    Choi, Seong-Ho; Chung, Jin-Won; Sung, Heungsup; Kim, Mi-Na; Kim, Sung-Han; Lee, Sang-Oh; Kim, Yang Soo; Woo, Jun Hee; Choi, Sang-Ho

    2012-09-01

    To investigate the impact of penicillin nonsusceptibility on clinical outcomes of patients with nonmeningeal Streptococcus pneumoniae bacteremia (SPB), a retrospective cohort study was performed. The characteristics of 39 patients with penicillin-nonsusceptible SPB (PNSPB) were compared to those of a group of age- and sex-matched patients (n = 78) with penicillin-susceptible SPB (PSSPB). Susceptibility to penicillin was redetermined by using the revised Clinical and Laboratory Standards Institute (CLSI) penicillin breakpoints in CLSI document M100-S18. Although the PNSPB group tended to have more serious initial manifestations than the PSSPB group, the two groups did not differ significantly in terms of their 30-day mortality rates (30.8% versus 23.1%; P = 0.37) or the duration of hospital stay (median number of days, 14 versus 12; P = 0.89). Broad-spectrum antimicrobial agents, such as extended-spectrum cephalosporins, vancomycin, and carbapenem, were frequently used in both the PNSPB and PSSPB groups. Multivariate analysis revealed that ceftriaxone nonsusceptibility (adjusted odds ratio [aOR] = 4.88; 95% confidence interval [CI] = 1.07 to 22.27; P = 0.041) was one of the independent risk factors for 30-day mortality. Thus, when the 2008 CLSI penicillin breakpoints are applied and the current clinical practice of using wide-spectrum empirical antimicrobial agents is pursued, fatal outcomes in patients with nonmeningeal SPB that can be attributed to penicillin nonsusceptibility are likely to be rare. Further studies that examine the clinical impact of ceftriaxone nonsusceptibility in nonmningeal SPB may be warranted.

  6. In vivo kinetic analysis of the penicillin biosynthesis pathway using PAA stimulus response experiments.

    PubMed

    Deshmukh, Amit T; Verheijen, Peter J T; Maleki Seifar, Reza; Heijnen, Joseph J; van Gulik, Walter M

    2015-11-01

    In this study we combined experimentation with mathematical modeling to unravel the in vivo kinetic properties of the enzymes and transporters of the penicillin biosynthesis pathway in a high yielding Penicillium chrysogenum strain. The experiment consisted of a step response experiment with the side chain precursor phenyl acetic acid (PAA) in a glucose-limited chemostat. The metabolite data showed that in the absence of PAA all penicillin pathway enzymes were expressed, leading to the production of a significant amount of 6-aminopenicillanic acid (6APA) as end product. After the stepwise perturbation with PAA, the pathway produced PenG within seconds. From the extra- and intracellular metabolite measurements, hypotheses for the secretion mechanisms of penicillin pathway metabolites were derived. A dynamic model of the penicillin biosynthesis pathway was then constructed that included the formation and transport over the cytoplasmic membrane of pathway intermediates, PAA and the product penicillin-G (PenG). The model parameters and changes in the enzyme levels of the penicillin biosynthesis pathway under in vivo conditions were simultaneously estimated using experimental data obtained at three different timescales (seconds, minutes, hours). The model was applied to determine changes in the penicillin pathway enzymes in time, calculate fluxes and analyze the flux control of the pathway. This led to a reassessment of the in vivo behavior of the pathway enzymes and in particular Acyl-CoA:Isopenicillin N Acyltransferase (AT).

  7. Penicillin G-Induced Chlamydial Stress Response in a Porcine Strain of Chlamydia pecorum

    PubMed Central

    Leonard, Cory Ann; Dewez, Frederic; Borel, Nicole

    2016-01-01

    Chlamydia pecorum causes asymptomatic infection and pathology in ruminants, pigs, and koalas. We characterized the antichlamydial effect of the beta lactam penicillin G on Chlamydia pecorum strain 1710S (porcine abortion isolate). Penicillin-exposed and mock-exposed infected host cells showed equivalent inclusions numbers. Penicillin-exposed inclusions contained aberrant bacterial forms and exhibited reduced infectivity, while mock-exposed inclusions contained normal bacterial forms and exhibited robust infectivity. Infectious bacteria production increased upon discontinuation of penicillin exposure, compared to continued exposure. Chlamydia-induced cell death occurred in mock-exposed controls; cell survival was improved in penicillin-exposed infected groups. Similar results were obtained both in the presence and in the absence of the eukaryotic protein translation inhibitor cycloheximide and at different times of initiation of penicillin exposure. These data demonstrate that penicillin G induces the chlamydial stress response (persistence) and is not bactericidal, for this chlamydial species/strain in vitro, regardless of host cell de novo protein synthesis. PMID:26997956

  8. Prevalence and characteristics of reported penicillin allergy in an urban outpatient adult population

    PubMed Central

    Agarwal, Shradha

    2014-01-01

    Penicillin allergy remains the most common drug allergy, with a reported prevalence of 10% in the United States. Epidemiology of penicillin allergy in outpatient populations is relatively scarce. This study sought to determine the prevalence and characteristics of reported penicillin allergy in an urban outpatient population and to identify trends in clinical evaluation and management from a tertiary center serving a large inner-city population. A retrospective review of electronic medical records was performed of adult patients seen in the Internal Medicine Associates Clinic of Mount Sinai Hospital between January 31, 2012, and July 31, 2012. Medical records were selected based on the documentation of penicillin in patient's allergy section. Of the 11,761 patients seen in the clinic, 1348 patients (11.5%) reported a history of penicillin allergy. The most common allergic reactions were rash (37%), unknown/undocumented (20.2%), hives (18.9%), swelling/angioedema (11.8%), and anaphylaxis (6.8%). There was an increased prevalence of penicillin allergy in female patients compared with male patients (odds ratio [OR] = 1.82; 95% CI = 1.60, 2.08; p < 0.0001), and there were significantly fewer Asians with penicillin allergy compared with Caucasians (OR = 0.51; 95% CI = 0.32, 0.83; p = 0.007). However, only 78 (6%) of the patients reporting penicillin allergy had a referral to an allergy specialist. Overall, improved referral to an allergist will help to identify patients who have penicillin allergy requiring avoidance. PMID:25584917

  9. Improvement of Aspergillus nidulans penicillin production by targeting AcvA to peroxisomes.

    PubMed

    Herr, Andreas; Fischer, Reinhard

    2014-09-01

    Aspergillus nidulans is able to synthesize penicillin and serves as a model to study the regulation of its biosynthesis. Only three enzymes are required to form the beta lactam ring tripeptide, which is comprised of l-cysteine, l-valine and l-aminoadipic acid. Whereas two enzymes, AcvA and IpnA localize to the cytoplasm, AatA resides in peroxisomes. Here, we tested a novel strategy to improve penicillin production, namely the change of the residence of the enzymes involved in the biosynthesis. We tested if targeting of AcvA or IpnA (or both) to peroxisomes would increase the penicillin yield. Indeed, AcvA peroxisomal targeting led to a 3.2-fold increase. In contrast, targeting IpnA to peroxisomes caused a complete loss of penicillin production. Overexpression of acvA, ipnA or aatA resulted in 1.4, 2.8 and 3.1-fold more penicillin, respectively in comparison to wildtype. Simultaneous overexpression of all three enzymes resulted even in 6-fold more penicillin. Combination of acvA peroxisomal targeting and overexpression of the gene led to 5-fold increase of the penicillin titer. At last, the number of peroxisomes was increased through overexpression of pexK. A strain with the double number of peroxisomes produced 2.3 times more penicillin. These results show that penicillin production can be triggered at several levels of regulation, one of which is the subcellular localization of the enzymes.

  10. Determination of eight penicillin antibiotics in pharmaceuticals, milk and porcine tissues by nano-liquid chromatography.

    PubMed

    Hsieh, Shih-Huan; Huang, Hsi-Ya; Lee, Szetsen

    2009-10-23

    This study describes the ability of nanoscale liquid chromatography (nano-LC) coupled with UV or mass spectrometry (MS) for the simultaneous determination of eight common penicillin antibiotics (amoxicillin, ampicillin, penicillin G, penicillin V, oxacillin, cloxacillin, nafcillin and dicloxacillin) in commercial samples (pharmaceuticals, milk, porcine tissues (liver and kidney)) for the first time. Material types of the on-column polymeric frits (polystyrene-based and polymethacrylate-based monoliths) and the packed stationary phase materials (C8 and C18 particles of 3 microm) used in the nano-LC for the influence of penicillin separation were evaluated. The nano-LC and MS parameters such as the composition and flow rate of mobile phase, capillary voltage and temperature of dry gas were examined in order to acquire high separation resolution and detection sensitivity for penicillin analyses. Furthermore, a home-made in-line filter (a nylon membrane of 0.2 microm pore size), was first used to connect with the flow cell of high sensitivity UV detector or the nanoelectrospray needle in MS detection. The result indicated it could effectively improve the reproducibility of penicillin mass signals or prolong the lifetime of the flow cell. The nano-LC methods provided good quantitative precisions in the range of 89.5-111.2% for UV detection at 0.5 microg/mL penicillins, and 83. 1-94.9% for MS detection at 5 mcirog/L penicillins), respectively, as well as offered stable retention repeatabilities (the relative standard deviation (RSD) of retention time was lower 0.30% in both the UV and MS detections). Compared to other LC-MS methods, the proposed nano-LC systems provided better detection sensitivity for these penicillins (the limits of detection (LOD) was of 2.27-4.06 microg/L for UV mode, and 0.01-0.51 microg/L for MS mode) when either UV or MS detector was employed.

  11. Is Penicillin Plus Gentamicin Synergistic against Clinical Group B Streptococcus isolates?: An In vitro Study

    PubMed Central

    Ruppen, Corinne; Lupo, Agnese; Decosterd, Laurent; Sendi, Parham

    2016-01-01

    Group B Streptococcus (GBS) is increasingly causing invasive infections in non-pregnant adults. Elderly patients and those with comorbidities are at increased risk. On the basis of previous studies focusing on neonatal infections, penicillin plus gentamicin is recommended for infective endocarditis (IE) and periprosthetic joint infections (PJI) in adults. The purpose of this study was to investigate whether a synergism with penicillin and gentamicin is present in GBS isolates that caused IE and PJI. We used 5 GBS isolates, two clinical strains and three control strains, including one displaying high-level gentamicin resistance (HLGR). The results from the checkerboard and time-kill assays (TKAs) were compared. For TKAs, antibiotic concentrations for penicillin were 0.048 and 0.2 mg/L, and for gentamicin 4 mg/L or 12.5 mg/L. In the checkerboard assay, the median fractional inhibitory concentration indices (FICIs) of all isolates indicated indifference. TKAs for all isolates failed to demonstrate synergism with penicillin 0.048 or 0.2 mg/L, irrespective of gentamicin concentrations used. Rapid killing was seen with penicillin 0.048 mg/L plus either 4 mg/L or 12.5 mg/L gentamicin, from 2 h up to 8 h hours after antibiotic exposure. TKAs with penicillin 0.2 mg/L decreased the starting inoculum below the limit of quantification within 4–6 h, irrespective of the addition of gentamicin. Fast killing was seen with penicillin 0.2 mg/L plus 12.5 mg/L gentamicin within the first 2 h. Our in vitro results indicate that the addition of gentamicin to penicillin contributes to faster killing at low penicillin concentrations, but only within the first few hours. Twenty-four hours after antibiotic exposure, PEN alone was bactericidal and synergism was not seen.

  12. Biological characterization of a new radioactive labeling reagent for bacterial penicillin-binding proteins

    SciTech Connect

    Preston, D.A.; Wu, C.Y.; Blaszczak, L.C.; Seitz, D.E.; Halligan, N.G. )

    1990-05-01

    Radiolabeled penicillin G is widely used as the imaging agent in penicillin-binding protein (PBP) assays. The disadvantages of most forms of labeled penicillin G are instability on storage and the long exposure times usually required for autoradiography or fluorography of electrophoretic gels. We investigated the utility of radioiodinated penicillin V as an alternative reagent. Radioiodination of p-(trimethylstannyl)penicillin V with ({sup 125}I)Na, using a modification of the chloramine-T method, is simple, high yielding, and site specific. We demonstrated the general equivalence of commercially obtained ({sup 3}H)penicillin G and locally synthesized ({sup 125}I)penicillin V (IPV) in their recognition of bacterial PBPs. Profiles of PBPs in membranes from Bacteroides fragilis, Escherichia coli, Providencia rettgeri, Staphylococcus aureus, Streptococcus pyogenes, Enterococcus faecalis, and Enterococcus faecium labeled with IPV or (3H)penicillin G were virtually identical. Use of IPV as the imaging agent in competition experiments for determination of the affinities of various beta-lactam antibiotics for the PBPs of E. coli yielded results similar to those obtained in experiments with ({sup 3}H)penicillin G. Dried electrophoretic gels from typical PBP experiments, using IPV at 37.3 Ci/mmol and 30 micrograms/ml, exposed X-ray film in 8 to 24 h. The stability of IPV on storage at 4{degrees}C was inversely proportional to specific activity. At 37.3 Ci/mmol and 60 micrograms/ml, IPV retained useful activity for at least 60 days at 4{degrees}C. IPV represents a practical and stable reagent for rapid PBP assays.

  13. Effects of immobilization on spermiogenesis

    NASA Technical Reports Server (NTRS)

    Meitner, E. R.

    1980-01-01

    The influence of immobilization stress on spermiogenesis in rats was investigated. After 96 hour immobilization, histological changes began to manifest themselves in the form of practically complete disappearance of cell population of the wall of seminiferous tubule as well as a markedly increased number of cells with pathologic mitoses. Enzymological investigations showed various changes of activity (of acid and alkaline phosphatase and nonspecific esterase) in the 24, 48, and 96 hour immobilization groups.

  14. [Progress in Proteomic Study of the Penicillin Producer---Penicillium Chrysogenum].

    PubMed

    Wang, Shun; Wang, Peihong; Zhang, Nan; Gao, Ruichang

    2015-12-01

    Penicillin is a kind of β-lactam drug which has been applied in the clinical treatment firstly in the world, and it has still been widely used at present. The synthesis and regulation mechanism of Penicillium chrysogenum, which is used to produce penicillin, has been studied quite maturely, but its proteomics research started relatively late and fewer reports were published. This paper reviews the synthesis and application of penicillin, transformation of Penicillium chrysogenum, and the research progress of its proteomics. On this basis, the study highlights the advantages of proteomics in the research of protein expression.

  15. [Progress in Proteomic Study of the Penicillin Producer---Penicillium Chrysogenum].

    PubMed

    Wang, Shun; Wang, Peihong; Zhang, Nan; Gao, Ruichang

    2015-12-01

    Penicillin is a kind of β-lactam drug which has been applied in the clinical treatment firstly in the world, and it has still been widely used at present. The synthesis and regulation mechanism of Penicillium chrysogenum, which is used to produce penicillin, has been studied quite maturely, but its proteomics research started relatively late and fewer reports were published. This paper reviews the synthesis and application of penicillin, transformation of Penicillium chrysogenum, and the research progress of its proteomics. On this basis, the study highlights the advantages of proteomics in the research of protein expression. PMID:27079113

  16. Increased production of penicillin-binding protein 2, increased detection of other penicillin-binding proteins, and decreased coagulase activity associated with glycopeptide resistance in Staphylococcus aureus.

    PubMed Central

    Moreira, B; Boyle-Vavra, S; deJonge, B L; Daum, R S

    1997-01-01

    The mechanism of glycopeptide resistance in the genus Staphylococcus is unknown. Since these antimicrobial compounds act by binding the peptidoglycan precursor terminus, the target of transglycosylase and transpeptidase enzymes, it was hypothesized that resistance might be mediated in Staphylococcus aureus by increased production or activity of these enzymes, commonly called penicillin-binding proteins (PBPs). To evaluate this possibility, glycopeptide-resistant mutants were prepared by passage of several clinical isolates of this species in nutrient broth containing successively increasing concentrations of the glycopeptide vancomycin or teicoplanin. Decreased coagulase activity and increased resistance to lysostaphin were uniformly present in the vancomycin-resistant mutants. Peptidoglycan cross-linking increased in one resistant isolate and decreased in two resistant isolates. The amounts of radioactive penicillin that bound to each PBP in susceptible and resistant strains were compared; PBP2 production was also evaluated by Western blotting. Increased penicillin labeling and production of PBP2 were found in all resistant derivatives selected by either vancomycin or teicoplanin. Moreover, the increase in PBP2 penicillin labeling occurred early in a series of vancomycin-selected derivatives and was strongly correlated (r > 0.9) with the increase in vancomycin and teicoplanin MIC. An increase in penicillin labeling also occurred, variably, in PBP1, PBP3, and/or PBP4. These data demonstrate a strong correlation between resistance to glycopeptides and increased PBP activity and/or production in S. aureus. Such an increase could allow PBPs to better compete with glycopeptides for the peptidoglycan precursor. PMID:9257762

  17. Synthesis and Kinetic Analysis of Two Conformationally Restricted Peptide Substrates of Escherichia coli Penicillin-Binding Protein 5.

    PubMed

    Nemmara, Venkatesh V; Nicholas, Robert A; Pratt, R F

    2016-07-26

    Escherichia coli PBP5 (penicillin-binding protein 5) is a dd-carboxypeptidase involved in bacterial cell wall maturation. Beyond the C-terminal d-alanyl-d-alanine moiety, PBP5, like the essential high-molecular mass PBPs, has little specificity for other elements of peptidoglycan structure, at least as elicited in vitro by small peptidoglycan fragments. On the basis of the crystal structure of a stem pentapeptide derivative noncovalently bound to E. coli PBP6 (Protein Data Bank entry 3ITB ), closely similar in structure to PBP5, we have modeled a pentapeptide structure at the active site of PBP5. Because the two termini of the pentapeptide are directed into solution in the PBP6 crystal structure, we then modeled a 19-membered cyclic peptide analogue by cross-linking the terminal amines by succinylation. An analogous smaller, 17-membered cyclic peptide, in which the l-lysine of the original was replaced by l-diaminobutyric acid, could also be modeled into the active site. We anticipated that, just as the reactivity of stem peptide fragments of peptidoglycan with PBPs in vivo may be entropically enhanced by immobilization in the polymer, so too would that of our cyclic peptides with respect to their acyclic analogues in vitro. This paper describes the synthesis of the peptides described above that were required to examine this hypothesis and presents an analysis of their structures and reaction kinetics with PBP5. PMID:27420403

  18. Physical and reactive extraction equilibria of penicillin G in a hydrogen-bond acceptor solvent system.

    PubMed

    Lee, Sang Cheol

    2006-01-01

    Physical and reactive extraction equilibria of penicillin G were investigated experimentally and theoretically in the existence of n-butyl acetate as a hydrogen-bond acceptor solvent. Physical extraction equilibrium experiments were carried out varying the pH of aqueous phase and overall penicillin concentration. We compared the experimental data with the calculated results from four physical extraction equilibrium models suggested here and obtained the most reasonable model. Also, penicillin G was reactively extracted using Amberlite LA-2 in n-butyl acetate. The experimental variables were pH of the aqueous phase, overall amine concentration, and overall penicillin concentration. A combined equilibrium model including our physical extraction equilibrium expression and the reactive extraction equilibrium expression suggested by Reschke and Schügerl was used so as to analyze the current reactive extraction equilibrium system. The calculated results from the reactive extraction equilibrium model were in good agreement with the experimental data.

  19. Prophylactic subconjunctival cefuroxime during cataract surgery in patients with a penicillin allergy.

    PubMed

    Mitra, Arijit; McElvanney, Andrena

    2006-01-01

    The incidence of cross-reaction after subconjunctival cefuroxime following cataract surgery in penicillin allergy patients is not common and therefore cefuroxime with its better spectrum of action and lower toxicity is probably a better choice than gentamycin.

  20. Onset of penicillin-induced bacteriolysis in staphylococci is cell cycle dependent.

    PubMed Central

    Maidhof, H; Johannsen, L; Labischinski, H; Giesbrecht, P

    1989-01-01

    Synchronously growing staphylococci were treated with "lytic" concentrations of penicillin at different stages of their division cycle. Coulter Counter measurements and light microscopy were used to determine the onset of bacteriolysis. Independent of the stage of the division cycle at which penicillin was added, (i) the cells were always able to perform the next cell division; (ii) the following division, however, did not take place; and (iii) instead, at this time, when the onset of the subsequent cell separation was observed in control cultures, lysis of the penicillin-treated cells occurred. These results support a recent model (P. Giesbrecht, H. Labischinski, and J. Wecke, Arch. Microbiol. 141:315-324, 1985) explaining penicillin-induced bacteriolysis of staphylococci as the result of a special morphogenetic mistake during cross wall formation. Images PMID:2703473

  1. Treatment of experimental pneumonia due to penicillin-resistant Streptococcus pneumoniae in immunocompetent rats.

    PubMed Central

    Gavaldà, J; Capdevila, J A; Almirante, B; Otero, J; Ruiz, I; Laguarda, M; Allende, H; Crespo, E; Pigrau, C; Pahissa, A

    1997-01-01

    A model of pneumonia due to Streptococcus pneumoniae resistant to penicillin was developed in immunocompetent Wistar rats and was used to evaluate the efficacies of different doses of penicillin, cefotaxime, cefpirome, and vancomycin. Adult Wistar rats were challenged by intratracheal inoculation with 3 x 10(9) CFU of one strain of S. pneumoniae resistant to penicillin (MICs of penicillin, cefotaxime, cefpirome, and vancomycin, 2, 1, 0.5, and 0.5 microg/ml, respectively) suspended in brain heart broth supplemented with 0.7% agar. The rats experienced a fatal pneumonia, dying within 5 days and with peak mortality (70 to 80%) occurring 48 to 72 h after infection, and the bacterial counts in the lungs persisted from 8.87 +/- 0.3 log10 CFU/g of lung at 24 h of the infection to 9.1 +/- 0.3 log10 CFU/g at 72 h. Four hours after infection the animals were randomized into the following treatment groups: (i) control without treatment, (ii) penicillin G at 100,000 IU/kg of body weight every 2 h, (iii) penicillin G at 250,000 IU/kg every 2 h, (iv) cefotaxime at 100 mg/kg every 2 h, (v) cefpirome at 200 mg/kg every 2 h, and (vi) vancomycin at 50 mg/kg every 8 h. Two different protocols were used for the therapeutic efficacy studies: four doses of beta-lactams and one dose of vancomycin or eight doses of beta-lactams and two doses of vancomycin. Results of the therapy for experimental pneumonia caused by penicillin-resistant S. pneumoniae showed that initially, all the antimicrobial agents tested had similar efficacies, but when we prolonged the treatment, higher doses of penicillin, cefotaxime, and cefpirome were more effective than penicillin at lower doses in decreasing the residual bacterial titers in the lungs. Also, when we extended the treatment, vancomycin was more efficacious than penicillin at lower doses but was less efficacious than higher doses of penicillin or cefpirome. The model that we have developed is simple and amenable for inducing pneumonia in

  2. Reported Rates of Diarrhea Following Oral Penicillin Therapy in Pediatric Clinical Trials

    PubMed Central

    Kuehn, Jemima; Ismael, Zareen; Long, Paul F.; Barker, Charlotte I.S.

    2015-01-01

    OBJECTIVES: Antibiotic-associated diarrhea (AAD) is a well-recognized adverse reaction to oral penicillins. This review analyzed the literature to determine the incidence of AAD following amoxicillin, amoxicillin/clavulanate, and penicillin V oral therapy in pediatric clinical trials. METHODS: An advanced search was conducted in MEDLINE and Embase databases for articles in any language reporting the incidence of AAD following oral penicillin therapy for any indicated infection in children (0–17 years). The search was limited to clinical trials. Articles were excluded if treatment was related to chronic conditions, involved concomitant antimicrobials, or if the dose or number of patients was not specified. RESULTS: Four hundred thirty-five articles relating to clinical trials were identified (307 from Embase; 128 from MEDLINE). Thirty-five articles reporting on 42 studies were included for analysis. The indications included acute otitis media, sinusitis, pharyngitis, and pneumonia. Thirty-three trials reported on amoxicillin/clavulanate, 6 on amoxicillin, and 3 on penicillin V. In total, the 42 trials included 7729 children who were treated with an oral penicillin. On average, 17.2% had AAD. Data were pooled for each penicillin. The AAD incidence was 19.8% for amoxicillin/clavulanate, 8.1% for amoxicillin, and 1.2% for penicillin V. The amoxicillin/clavulanate data were analyzed according to formulation: pooled-average. The incidence of ADD was 24.6% for the 4:1 formulation, 12.8% for the 7:1 formulation, 19.0% for the 8:1 formulation, and 20.2% for the 14:1 formulation. CONCLUSIONS: These results demonstrate substantially increased incidence of AAD following use of amoxicillin/clavulanate, compared to use of amoxicillin and penicillin V, as well as varying AAD rates with diffierent amoxicillin/clavulanate formulations. These findings warrant consideration when prescribing. The underlying mechanisms of AAD in children remain unclear. PMID:25964726

  3. In vitro activity of moxalactam alone and in combination with penicillin against common meningeal pathogens.

    PubMed

    Azimi, P H; Dunphy, M G

    1982-03-01

    Moxalactam demonstrated marked activity against beta-lactamase-positive and -negative Haemophilus influenzae, Streptococcus pneumoniae, and Neisseria meningitidis by both standard minimal inhibitory concentration testing and growth curve studies. Moxalactam was ineffective against S. pneumoniae partially susceptible to penicillin G. Moxalactam (5 micrograms/ml) and penicillin (1 microgram/ml) in combination were indifferent to each other's antibacterial activity, exerting neither synergism nor antagonism against these organisms.

  4. The Association of Viral Activation with Penicillin Toxicity in Guinea Pigs and Hamsters 1

    PubMed Central

    Green, Robert H.

    1974-01-01

    Penicillin toxicity in the guinea pig may be manifested in several different ways, and it is proposed that these toxic effects be categorized into three syndromes: (1) toxic syndrome, characterized by acute fatal illness; (2) hemorrhagic syndrome, characterized by delayed illness with leukopenia and thrombocytopenia, and culminating in massive visceral hemorrhages; (3) chronic syndrome, characterized by retardation of growth and alopecia, a condition somewhat resembling “runt disease.” A virus having some of the properties of a parvovirus has been isolated repeatedly from animals ill or dying of penicillin-induced disease. This finding has been construed as being activation of a latent virus by this antibiotic, but the relationship, if any, of the phenomenon of viral activation to the syndromes produced by penicillin and its frequent lethal toxicity is unknown. That a strong association exists, however, has been established. Of some 60 guinea pigs which received injections of penicillin three developed tumors and four others were found to have gallstones. A virus similar or identical to the guinea pig virus also has been isolated from hamsters dying of penicillin-induced disease. It is hypothesized that the absorption of endotoxin, resulting from the well known change in intestinal flora caused by penicillin, produces a state of immunodeficiency which regularly gives rise to activation of a latent virus, and perhaps, rarely, to the development of malignant neoplasms. PMID:4446629

  5. The role of the media in influencing public attitudes to penicillin during World War II.

    PubMed

    Shama, Gilbert

    2015-01-01

    Penicillin's trajectory towards becoming an effective antibacterial chemotherapeutic agent took place during World War II. Its strategic military value was immediately recognised by the Allies, and mass production was undertaken with the prime objective of meeting the needs of the armed forces. News of its development came to be widely reported on in the media and is examined here. These reports frequently combined accounts of penicillin's prodigious clinical effectiveness with the fact that it was to remain unavailable to the civilian population essentially until the war had ended. More penicillin was to be made available to the civilian population in the United States than in Britain, but the sense that it was severely rationed remained as high. It was in response to this that the idea of "homemade penicillin" was hatched. News of this was also widely promulgated by both the British and American media. Although the numbers treated with penicillin produced in this way was never to be significant, knowledge of the existence of such endeavours may have served to assuage in some measure the feelings of frustration felt by the civilian population at penicillin's non-availability. PMID:26012339

  6. Meta-analysis of ceftriaxone compared with penicillin for the treatment of syphilis.

    PubMed

    Liang, Zhen; Chen, Ya-Ping; Yang, Chun-Sheng; Guo, Wen; Jiang, Xiao-Xiao; Xu, Xi-Feng; Feng, Shou-Xin; Liu, Yan-Qun; Jiang, Guan

    2016-01-01

    Penicillin is the gold standard for treating syphilis. However, allergic reactions, poor drug tolerance and limited efficacy in patients remain a challenging problem. The objective of this meta-analysis was to compare the efficacy of ceftriaxone and penicillin based on data obtained from published randomised controlled trials (RCTs). The Cochrane Library, Medline, EBSCO, EMBASE and Ovid databases were searched for RCTs of ceftriaxone vs. penicillin for the treatment of syphilis. Estimated risk ratios (RRs) and 95% confidence intervals (CIs) were used to investigate the following outcome measures: 3-month response rate; 6-month response rate; 12-month response rate; relapse rate; serofast rate; and failure rate. Seven RCTs involving 281 participants (159 patients who received ceftriaxone and 122 patients who received penicillin) were included in the meta-analysis. There were no significant differences in 3-month response rate (RR=1.12, 95% CI 0.89-1.42), 6-month response rate (RR=1.02, 95% CI 0.75-1.38), 12-month response rate (RR=1.04, 95% CI 0.82-1.32), relapse rate (RR=0.91, 95% CI 0.45-1.84), serofast rate (RR=0.69, 95% CI 0.22-2.12) or failure rate (RR=0.66, 95% CI 0.03-15.76) in patients treated with ceftriaxone compared with those treated with penicillin. In conclusion, there is no evidence in the literature that ceftriaxone is less efficient than penicillin.

  7. Removal of Penicillin G and Erythromycin with Ionizing Radiation Followed by Biological Treatment.

    PubMed

    Ben Salem, Issam; Mezni, Mohamed; Boulila, Abdennacer; Hamdi, Mokhtar; Saidi, Mouldi

    2016-10-01

    The decomposition of penicillin G and erythromycin antibiotics at concentration of 0.2 mg ml(-1) by gamma irradiation at 50 kGy followed by biological treatment with Cupriavidus metallidurans CH34 was evaluated. Degradation of penicillin G and erythromycin was analyzed using nuclear magnetic resonance analysis (NMR), fourier transform infrared spectroscopy (FTIR), and chemical oxygen demand (COD). The exposure to the absorbed dose of 50 kGy caused degradation of penicillin G and erythromycin in the aqueous solution. The complete disappearance of NMR and FTIR peaks following irradiation confirmed the breakage of the β-lactam ring in penicillin G, and the decarboxylation and cleavage of the thiazolidine ring and for erythromycin, the complete destruction of the three aromatic rings. Irradiation alone removed 52.8 and 65.5 % of penicillin G and erythromycin, respectively. Further reduction to 12.6 and 14 % of the original penicillin G and erythromycin COD, respectively, was achieved using treatment of the irradiation products with C. metallidurans.

  8. The role of the media in influencing public attitudes to penicillin during World War II.

    PubMed

    Shama, Gilbert

    2015-01-01

    Penicillin's trajectory towards becoming an effective antibacterial chemotherapeutic agent took place during World War II. Its strategic military value was immediately recognised by the Allies, and mass production was undertaken with the prime objective of meeting the needs of the armed forces. News of its development came to be widely reported on in the media and is examined here. These reports frequently combined accounts of penicillin's prodigious clinical effectiveness with the fact that it was to remain unavailable to the civilian population essentially until the war had ended. More penicillin was to be made available to the civilian population in the United States than in Britain, but the sense that it was severely rationed remained as high. It was in response to this that the idea of "homemade penicillin" was hatched. News of this was also widely promulgated by both the British and American media. Although the numbers treated with penicillin produced in this way was never to be significant, knowledge of the existence of such endeavours may have served to assuage in some measure the feelings of frustration felt by the civilian population at penicillin's non-availability.

  9. Removal of Penicillin G and Erythromycin with Ionizing Radiation Followed by Biological Treatment.

    PubMed

    Ben Salem, Issam; Mezni, Mohamed; Boulila, Abdennacer; Hamdi, Mokhtar; Saidi, Mouldi

    2016-10-01

    The decomposition of penicillin G and erythromycin antibiotics at concentration of 0.2 mg ml(-1) by gamma irradiation at 50 kGy followed by biological treatment with Cupriavidus metallidurans CH34 was evaluated. Degradation of penicillin G and erythromycin was analyzed using nuclear magnetic resonance analysis (NMR), fourier transform infrared spectroscopy (FTIR), and chemical oxygen demand (COD). The exposure to the absorbed dose of 50 kGy caused degradation of penicillin G and erythromycin in the aqueous solution. The complete disappearance of NMR and FTIR peaks following irradiation confirmed the breakage of the β-lactam ring in penicillin G, and the decarboxylation and cleavage of the thiazolidine ring and for erythromycin, the complete destruction of the three aromatic rings. Irradiation alone removed 52.8 and 65.5 % of penicillin G and erythromycin, respectively. Further reduction to 12.6 and 14 % of the original penicillin G and erythromycin COD, respectively, was achieved using treatment of the irradiation products with C. metallidurans. PMID:27447798

  10. Fluoroquinolone Resistance in Penicillin-resistant Streptococcus pneumoniae Clones, Spain

    PubMed Central

    Balsalobre, Luz; Ardanuy, Carmen; Fenoll, Asunción; Pérez-Trallero, Emilio; Liñares, Josefina

    2004-01-01

    Among 2,882 Streptococcus pneumoniae sent to the Spanish Reference Laboratory during 2002, 75 (2.6%) were ciprofloxacin-resistant. Resistance was associated with older patients (3.9% in adults and 7.2% in patients >65 years of age), with isolation from noninvasive sites (4.3% vs. 1.0%), and with penicillin and macrolide resistance. Among 14 low-level resistant (MIC 4–8 µg/mL) strains, 1 had a fluoroquinolone efflux phenotype, and 13 showed single ParC changes. The 61 high-level ciprofloxacin-resistant (MIC >16 µg/mL) strains showed either two or three changes at ParC, ParE, and GyrA. Resistance was acquired either by point mutation (70 strains) or by recombination with viridans streptococci (4 strains) at the topoisomerase II genes. Although 36 pulsed-field gel electrophoresis patterns were observed, 5 international multiresistant clones (Spain23F-1, Spain6B-2, Spain9V-3, Spain14-5 and Sweden15A-25) accounted for 35 (46.7%) of the ciprofloxacin-resistant strains. Continuous surveillance is needed to prevent the dissemination of these clones. PMID:15504260

  11. Plutonium Immobilization Canister Loading

    SciTech Connect

    Hamilton, E.L.

    1999-01-26

    This disposition of excess plutonium is determined by the Surplus Plutonium Disposition Environmental Impact Statement (SPD-EIS) being prepared by the Department of Energy. The disposition method (Known as ''can in canister'') combines cans of immobilized plutonium-ceramic disks (pucks) with vitrified high-level waste produced at the SRS Defense Waste Processing Facility (DWPF). This is intended to deter proliferation by making the plutonium unattractive for recovery or theft. The envisioned process remotely installs cans containing plutonium-ceramic pucks into storage magazines. Magazines are then remotely loaded into the DWPF canister through the canister neck with a robotic arm and locked into a storage rack inside the canister, which holds seven magazines. Finally, the canister is processed through DWPF and filled with high-level waste glass, thereby surrounding the product cans. This paper covers magazine and rack development and canister loading concepts.

  12. Remote handling in the Plutonium Immobilization Project -- Second stage immobilization

    SciTech Connect

    Kriikku, E.

    1999-12-21

    The Savannah River Site (SRS) will immobilize excess plutonium in ceramic pucks and seal the pucks inside welded cans. Automated equipment will place these cans in magazines and the magazines in a Defense Waste Processing Facility (DWPF) canister. The DWPF will fill the canister with glass for permanent storage. Due to the radiation, remote equipment will perform these operations in a contained environment. The Plutonium Immobilization Project is in the conceptual design stage and the facility will begin operation in 2008. This paper discusses the Plutonium Immobilization Project phase 2 automation equipment conceptual design, equipment design, and work completed.

  13. The long postwar and the politics of penicillin: early circulation and smuggling in Spain, 1944-1954.

    PubMed

    Santesmases, María Jesús

    2014-01-01

    In this paper I explore the early circulation of penicillin. I review the early distribution in Spain of a scarce product, reflect on the available sources about the illegal penicillin trade and discuss some cases of smuggling. I argue the early distribution of penicillin involved time and geography, a particular chronology of post Second World War geopolitics. Penicillin practices and experiences belong to this period, in a dictatorship that tolerated smuggling and illegal trade of other products, some, like penicillin, produced in neighbouring countries. As a commodity that crossed borders, penicillin, transiting between the law and hidden trade, between countries and social domains--between war fronts and from a war front to an urban site to be sold--reveals practices of the early years of prosperity in the 1950s. These transits were permanent tests of a society based on taxes and exchanges, law and bureaucracy, control, discipline and the creation of standards. PMID:26054216

  14. The long postwar and the politics of penicillin: early circulation and smuggling in Spain, 1944-1954.

    PubMed

    Santesmases, María Jesús

    2014-01-01

    In this paper I explore the early circulation of penicillin. I review the early distribution in Spain of a scarce product, reflect on the available sources about the illegal penicillin trade and discuss some cases of smuggling. I argue the early distribution of penicillin involved time and geography, a particular chronology of post Second World War geopolitics. Penicillin practices and experiences belong to this period, in a dictatorship that tolerated smuggling and illegal trade of other products, some, like penicillin, produced in neighbouring countries. As a commodity that crossed borders, penicillin, transiting between the law and hidden trade, between countries and social domains--between war fronts and from a war front to an urban site to be sold--reveals practices of the early years of prosperity in the 1950s. These transits were permanent tests of a society based on taxes and exchanges, law and bureaucracy, control, discipline and the creation of standards.

  15. Role of penA polymorphisms for penicillin susceptibility in Neisseria lactamica and Neisseria meningitidis.

    PubMed

    Karch, André; Vogel, Ulrich; Claus, Heike

    2015-10-01

    In meningococci, reduced penicillin susceptibility is associated with five specific mutations in the transpeptidase region of penicillin binding protein 2 (PBP2). We showed that the same set of mutations was present in 64 of 123 Neisseria lactamica strains obtained from a carriage study (MIC range: 0.125-2.0mg/L). The PBP2 encoding penA alleles in these strains were genetically similar to those found in intermediate resistant meningococci suggesting frequent interspecies genetic exchange. Fifty-six N. lactamica isolates with mostly lower penicillin MICs (range: 0.064-0.38mg/L) exhibited only three of the five mutations. The corresponding penA alleles were unique to N. lactamica and formed a distinct genetic clade. PenA alleles with no mutations on the other hand were unique to meningococci. Under penicillin selective pressure, genetic transformation of N. lactamica penA alleles in meningococci was only possible for alleles encoding five mutations, but not for those encoding three mutations; the transfer resulted in MICs comparable to those of meningococci harboring penA alleles that encoded PBP2 with five mutations, but considerably lower than those of the corresponding N. lactamica donor strains. Due to a transformation barrier the complete N. lactamica penA could not be transformed into N. meningitidis. In summary, penicillin MICs in N. lactamica were associated with the number of mutations in the transpeptidase region of PBP2. Evidence for interspecific genetic transfer was only observed for penA alleles associated with higher MICs, suggesting that alleles encoding only three mutations in the transpeptidase region are biologically not effective in N. meningitidis. Factors other than PBP2 seem to be responsible for the high levels of penicillin resistance in N. lactamica. A reduction of penicillin susceptibility in N. meningitidis by horizontal gene transfer from N. lactamica is unlikely to happen.

  16. Use of cephalosporins in patients with immediate penicillin hypersensitivity: cross-reactivity revisited.

    PubMed

    Lee, Q U

    2014-10-01

    A 10% cross-reactivity rate is commonly cited between penicillins and cephalosporins. However, this figure originated from studies in the 1960s and 1970s which included first-generation cephalosporins with similar side-chains to penicillins. Cephalosporins were frequently contaminated by trace amount of penicillins at that time. The side-chain hypothesis for beta-lactam hypersensitivity is supported by abundant scientific evidence. Newer generations of cephalosporins possess side-chains that are dissimilar to those of penicillins, leading to low cross-reactivity. In the assessment of cross-reactivity between penicillins and cephalosporins, one has to take into account the background beta-lactam hypersensitivity, which occurs in up to 10% of patients. Cross-reactivity based on skin testing or in-vitro test occurs in up to 50% and 69% of cases, respectively. Clinical reactivity and drug challenge test suggest an average cross-reactivity rate of only 4.3%. For third- and fourth-generation cephalosporins, the rate is probably less than 1%. Recent international guidelines are in keeping with a low cross-reactivity rate. Despite that, the medical community in Hong Kong remains unnecessarily skeptical. Use of cephalosporins in patients with penicillin hypersensitivity begins with detailed history and physical examination. Clinicians can choose a cephalosporin with a different side-chain. Skin test for penicillin is not predictive of cephalosporin hypersensitivity, while cephalosporin skin test is not sensitive. Drug provocation test by experienced personnel remains the best way to exclude or confirm the diagnosis of drug hypersensitivity and to find a safe alternative for future use. A personalised approach to cross-reactivity is advocated.

  17. Clinical Pharmacokinetics of Penicillins, Cephalosporins and Aminoglycosides in the Neonate: A Review

    PubMed Central

    Pacifici, Gian Maria

    2010-01-01

    Bacterial infections are common in the neonates and are a major cause of morbidity and mortality. Sixty percent of preterm infants admitted to neonatal intensive care units received at least one antibiotic during the first week of life. Penicillins, aminoglycosides and cephalosporins comprised 53, 43 and 16%, respectively. Kinetic parameters such as the half-life (t1/2), clearance (Cl), and volume of distribution (Vd) change with development, so the kinetics of penicillins, cephalosporins and aminoglycosides need to be studied in order to optimise therapy with these drugs. The aim of this study is to review the pharmacokinetics of penicillins, cephalosporins and aminoglycosides in the neonate in a single article in order to provide a critical analysis of the literature and thus provide a useful tool in the hands of physicians. The bibliographic search was performed electronically using PubMed, as the search engine, until February 2nd, 2010. Medline search terms were as follows: pharmacokinetics AND (penicillins OR cephalosporins OR aminoglycosides) AND infant, newborn, limiting to humans. Penicillins, cephalosporins and aminoglycosides are fairly water soluble and are mainly eliminated by the kidneys. The maturation of the kidneys governs the pharmacokinetics of penicillins, cephalosporins and aminoglycosides in the neonate. The renal excretory function is reduced in preterms compared to term infants and Cl of these drugs is reduced in premature infants. Gestational and postnatal ages are important factors in the maturation of the neonate and, as these ages proceed, Cl of penicillins, cephalosporins and aminoglycosides increases. Cl and t1/2 are influenced by development and this must be taken into consideration when planning a dosage regimen with these drugs. More pharmacokinetic studies are required to ensure that the dose recommended for the treatment of sepsis in the neonate is evidence based. PMID:27713367

  18. Interspecies Mixed-Effect Pharmacokinetic Modeling of Penicillin G in Cattle and Swine

    PubMed Central

    Li, Mengjie; Gehring, Ronette; Tell, Lisa; Baynes, Ronald; Huang, Qingbiao

    2014-01-01

    Extralabel drug use of penicillin G in food-producing animals may cause an excess of residues in tissue which will have the potential to damage human health. Of all the antibiotics, penicillin G may have the greatest potential for producing allergic responses to the consumer of food animal products. There are, however, no population pharmacokinetic studies of penicillin G for food animals. The objective of this study was to develop a population pharmacokinetic model to describe the time-concentration data profile of penicillin G across two species. Data were collected from previously published pharmacokinetic studies in which several formulations of penicillin G were administered to diverse populations of cattle and swine. Liver, kidney, and muscle residue data were also used in this study. Compartmental models with first-order absorption and elimination were fit to plasma and tissue concentrations using a nonlinear mixed-effect modeling approach. A 3-compartment model with extra tissue compartments was selected to describe the pharmacokinetics of penicillin G. Typical population parameter estimates (interindividual variability) were central volumes of distribution of 3.45 liters (12%) and 3.05 liters (8.8%) and central clearance of 105 liters/h (32%) and 16.9 liters/h (14%) for cattle and swine, respectively, with peripheral clearance of 24.8 liters/h (13%) and 9.65 liters/h (23%) for cattle and 13.7 liters/h (85%) and 0.52 liters/h (40%) for swine. Body weight and age were the covariates in the final pharmacokinetic models. This study established a robust model of penicillin for a large and diverse population of food-producing animals which could be applied to other antibiotics and species in future analyses. PMID:24867969

  19. [Open comparative study between the combination clyndamicin/gentamycin and penicillin/gentamycin in septic abortion].

    PubMed

    French, A R; Kennion, G

    1985-01-01

    Septic abortion is not uncommon in countries where abortion is illegal, and antibiotics are second only to uterine evacuation in the treatment of such cases. Although the combination of penicillin and gentamycin has given excellent results, the high incidence of Bacteroides fragilis and other anerobics in septic abortion prompted a comparison of penicillin and gentamycin with clindamycin and gentamycin at the Hospital Santo Tomas in Panama City, Panama, beginning in May 1984. Among 30 febrile patients with diagnoses of septic abortion, 14 were treated with penicillin/gentamycin and 16 with clindamycin/gentamycin. The penicillin group ranged in age from 17-29 with an average age of 21.9, while the clindamycin group ranged from 18-32 years with an average of 24.3. The average gestational ages were 10.2 weeks for the penicillin group and 10.7 for the clindamycin group. The average body temperature of both groups was 38.9 degrees Celsius. 1 patient had a blood pressure of 80/60 without clinical evidence of shock. The average duration of fever was 43 hours in the penicillin group and 40.6 hours in the clindamycin group. The hospital stay ranged from 3-7 days with an average of 5.4 in the penicillin group and from 3-6 days with an average of 4.2 in the clindamycin group. Patients recovered rapidly after uterine curettage and initiation of antibiotic therapy. Bacteremia was not detected in any patient. Tolerance to the drugs was similar in both groups.

  20. Non-toxigenic penicillin-resistant cutaneous C. diphtheriae infection: a case report and review of the literature.

    PubMed

    FitzGerald, Rosemarie Philippa; Rosser, Andrew J; Perera, Dona Nelun

    2015-01-01

    Here, we report a case of non-toxigenic Corynebacterium diphtheriae in a previously healthy 14-year-old girl that was acquired in Ethiopia and presented locally. This is the first clinical case of penicillin-resistant C. diphtheriae in the UK. This is significant finding because penicillin is the recommended first-line agent for the prophylaxis against and treatment of C. diphtheriae in patients who are not allergic to penicillin.

  1. Crystal Structures of Penicillin-Binding Protein 2 From Penicillin-Susceptible And -Resistant Strains of Neisseria Gonorrhoeae Reveal An Unexpectedly Subtle Mechanism for Antibiotic Resistance

    SciTech Connect

    Powell, A.J.; Tomberg, J.; Deacon, A.M.; Nicholas, R.A.; Davies, C.

    2009-05-21

    Penicillin-binding protein 2 (PBP2) from N. gonorrhoeae is the major molecular target for {beta}-lactam antibiotics used to treat gonococcal infections. PBP2 from penicillin-resistant strains of N. gonorrhoeae harbors an aspartate insertion after position 345 (Asp-345a) and 4-8 additional mutations, but how these alter the architecture of the protein is unknown. We have determined the crystal structure of PBP2 derived from the penicillin-susceptible strain FA19, which shows that the likely effect of Asp-345a is to alter a hydrogen-bonding network involving Asp-346 and the SXN triad at the active site. We have also solved the crystal structure of PBP2 derived from the penicillin-resistant strain FA6140 that contains four mutations near the C terminus of the protein. Although these mutations lower the second order rate of acylation for penicillin by 5-fold relative to wild type, comparison of the two structures shows only minor structural differences, with the positions of the conserved residues in the active site essentially the same in both. Kinetic analyses indicate that two mutations, P551S and F504L, are mainly responsible for the decrease in acylation rate. Melting curves show that the four mutations lower the thermal stability of the enzyme. Overall, these data suggest that the molecular mechanism underlying antibiotic resistance contributed by the four mutations is subtle and involves a small but measurable disordering of residues in the active site region that either restricts the binding of antibiotic or impedes conformational changes that are required for acylation by {beta}-lactam antibiotics.

  2. Crystal structures of penicillin-binding protein 2 from penicillin-susceptible and -resistant strains of Neisseria gonorrhoeae reveal an unexpectedly subtle mechanism for antibiotic resistance.

    PubMed

    Powell, Ailsa J; Tomberg, Joshua; Deacon, Ashley M; Nicholas, Robert A; Davies, Christopher

    2009-01-01

    Penicillin-binding protein 2 (PBP2) from N. gonorrhoeae is the major molecular target for beta-lactam antibiotics used to treat gonococcal infections. PBP2 from penicillin-resistant strains of N. gonorrhoeae harbors an aspartate insertion after position 345 (Asp-345a) and 4-8 additional mutations, but how these alter the architecture of the protein is unknown. We have determined the crystal structure of PBP2 derived from the penicillin-susceptible strain FA19, which shows that the likely effect of Asp-345a is to alter a hydrogen-bonding network involving Asp-346 and the SXN triad at the active site. We have also solved the crystal structure of PBP2 derived from the penicillin-resistant strain FA6140 that contains four mutations near the C terminus of the protein. Although these mutations lower the second order rate of acylation for penicillin by 5-fold relative to wild type, comparison of the two structures shows only minor structural differences, with the positions of the conserved residues in the active site essentially the same in both. Kinetic analyses indicate that two mutations, P551S and F504L, are mainly responsible for the decrease in acylation rate. Melting curves show that the four mutations lower the thermal stability of the enzyme. Overall, these data suggest that the molecular mechanism underlying antibiotic resistance contributed by the four mutations is subtle and involves a small but measurable disordering of residues in the active site region that either restricts the binding of antibiotic or impedes conformational changes that are required for acylation by beta-lactam antibiotics. PMID:18986991

  3. The in vitro antibacterial activity of ceftriaxone against Streptococcus pyogenes is unrelated to penicillin-binding protein 4.

    PubMed

    Yan, S; Mendelman, P M; Stevens, D L

    1993-07-01

    The in vitro activities of penicillin and ceftriaxone were compared against 29 strains of Streptococcus pyogenes with the result that ceftriaxone showed greater activity than penicillin. The morphological changes induced by 1/2 and 1x MIC concentrations of penicillin and ceftriaxone, respectively, were very similar using scanning electron microscopy. Competitive binding studies using 'cold' penicillin or ceftriaxone as inhibitors of radiolabeled penicillin binding demonstrated that ceftriaxone had a very low affinity for penicillin binding protein (PBP) 4 compared to that of penicillin. Since ceftriaxone had greater antibacterial activity, this suggests that PBP 4 may not be important to the in vitro activity of ceftriaxone. In contrast, the IC50 for ceftriaxone was much lower (> 200 fold) for PBPs 2 and 3 compared to PBP 4, suggesting greater avidity of these high molecular mass PBPs for ceftriaxone. These data may at least in part explain the superior in vitro activity of ceftriaxone compared to penicillin against S. pyogenes. These data, together with the observation that PBP 1 was saturated at a lower concentration of penicillin than any of the other PBPs, suggest that the inhibition of PBPs 1, 2, and 3 mediates the bactericidal activity of beta-lactam antibiotics against group A streptococci. PMID:8354465

  4. Eradication of H. pylori infection in patients allergic to penicillin using triple therapy with a PPI, metronidazole and sitafloxacin.

    PubMed

    Furuta, Takahisa; Sugimoto, Mitsushige; Yamade, Mihoko; Uotani, Takahiro; Sahara, Shu; Ichikawa, Hitomi; Kagami, Takuma; Yamada, Takanori; Osawa, Satoshi; Sugimoto, Ken; Watanabe, Hiroshi; Umemura, Kazuo

    2014-01-01

    Eradication of H. pylori in patients allergic to penicillin should be performed using regimens without penicillin derivatives. We treated a total of 28 patients allergic to penicillin with a proton pump inhibitor (PPI), metronidazole (250 mg bid) and sitafloxacin (100 mg bid) for one to two weeks. At four to eight weeks after the treatment, the patients underwent the [(13)C]-urea breath test. The overall eradication rate was 100.0%. Mild adverse events were observed. Triple therapy with a PPI, metronidazole and sitafloxacin is well tolerated and effective for the eradication of H. pylori in patients allergic to penicillin. PMID:24633026

  5. Treating Wastewater With Immobilized Enzymes

    NASA Technical Reports Server (NTRS)

    Jolly, Clifford D.

    1991-01-01

    Experiments show enzymes are immobilized on supporting materials to make biocatalyst beds for treatment of wastewater. With suitable combination of enzymes, concentrations of various inorganic and organic contaminants, including ammonia and urea, reduced significantly.

  6. Penicillin Induced Persistence in Chlamydia trachomatis: High Quality Time Lapse Video Analysis of the Developmental Cycle

    PubMed Central

    Barlow, David; Wang, Yibing; Salim, Omar; Lambden, Paul R.; Clarke, Ian N.

    2009-01-01

    Background Chlamydia trachomatis is a major human pathogen with a unique obligate intracellular developmental cycle that takes place inside a modified cytoplasmic structure known as an inclusion. Following entry into a cell, the infectious elementary body (EB) differentiates into a non - infectious replicative form known as a reticulate body (RB). RBs divide by binary fission and at the end of the cycle they redifferentiate into EBs. Treatment of C.trachomatis with penicillin prevents maturation of RBs which survive and enlarge to become aberrant RBs within the inclusion in a non - infective persistent state. Persistently infected individuals may be a reservoir for chlamydial infection. The C.trachomatis genome encodes the enzymes for peptidoglycan (PG) biosynthesis but a PG sacculus has never been detected. This coupled to the action of penicillin is known as the chlamydial anomaly. We have applied video microscopy and quantitative DNA assays to the chlamydial developmental cycle to assess the effects of penicillin treatment and establish a framework for investigating penicillin induced chlamydial persistence. Principal Findings Addition of penicillin at the time of cell infection does not prevent uptake and the establishment of an inclusion. EB to RB transition occurs but bacterial cytokinesis is arrested by the second binary fission. RBs continue to enlarge but not divide in the presence of penicillin. The normal developmental cycle can be recovered by the removal of penicillin although the large, aberrant RBs do not revert to the normal smaller size but remain present to the completion of the developmental cycle. Chromosomal and plasmid DNA replication is unaffected by the addition of penicillin but the arrest of bacterial cytokinesis under these conditions results in RBs accumulating multiple copies of the genome. Conclusions We have applied video time lapse microscopy to the study of the chlamydial developmental cycle. Linked with accurate measures of genome

  7. Penicillin Binding Proteins as Danger Signals: Meningococcal Penicillin Binding Protein 2 Activates Dendritic Cells through Toll-Like Receptor 4

    PubMed Central

    Hill, Marcelo; Deghmane, Ala-Eddine; Segovia, Mercedes; Zarantonelli, Maria Leticia; Tilly, Gaëlle; Blancou, Philippe; Bériou, Gaëlle; Josien, Régis; Anegon, Ignacio; Hong, Eva; Ruckly, Corinne; Antignac, Aude; Ghachi, Meriem El; Boneca, Ivo Gomperts

    2011-01-01

    Neisseria meningitidis is a human pathogen responsible for life-threatening inflammatory diseases. Meningococcal penicillin-binding proteins (PBPs) and particularly PBP2 are involved in bacterial resistance to β-lactams. Here we describe a novel function for PBP2 that activates human and mouse dendritic cells (DC) in a time and dose-dependent manner. PBP2 induces MHC II (LOGEC50 = 4.7 µg/ml±0.1), CD80 (LOGEC50 = 4.88 µg/ml±0.15) and CD86 (LOGEC50 = 5.36 µg/ml±0.1). This effect was abolished when DCs were co-treated with anti-PBP2 antibodies. PBP2-treated DCs displayed enhanced immunogenic properties in vitro and in vivo. Furthermore, proteins co-purified with PBP2 showed no effect on DC maturation. We show through different in vivo and in vitro approaches that this effect is not due to endotoxin contamination. At the mechanistic level, PBP2 induces nuclear localization of p65 NF-kB of 70.7±5.1% cells versus 12±2.6% in untreated DCs and needs TLR4 expression to mature DCs. Immunoprecipitation and blocking experiments showed that PBP2 binds TLR4. In conclusion, we describe a novel function of meningococcal PBP2 as a pathogen associated molecular pattern (PAMP) at the host-pathogen interface that could be recognized by the immune system as a danger signal, promoting the development of immune responses. PMID:22046231

  8. Outpatient penicillin use after negative skin testing and drug challenge in a pediatric population.

    PubMed

    Picard, Matthieu; Paradis, Louis; Nguyen, Mélanie; Bégin, Philippe; Paradis, Jean; Des Roches, Anne

    2012-01-01

    The practice of elective penicillin skin testing could be compromised by the fact that patients, their parents, or their physicians remain reluctant to reuse penicillin-class antibiotics (PCAs) despite a negative evaluation by an allergist. This study addresses reuse of PCAs in a pediatric population after negative penicillin skin testing and drug challenge and factors associated with its reluctance. All children evaluated for a history of penicillin allergy at the CHU Sainte-Justine Allergy Clinic between January 1998 and June 2000 with negative skin testing and drug challenge were included in the study. A telephone survey was conducted between May and October 2002 to assess the perception of the initial reaction by the parents, subsequent use of antibiotics, and antibiotic-related adverse reactions. Among the 200 children selected, parents of 170 (85%) children completed the survey. Since the allergist evaluation, 130 (76%) children had received antibiotics. PCA was used in 59 (45%) children. Parents of 24 (18%) children refused PCAs because they still feared an adverse reaction. They were more likely to have been very frightened by their child's allergic reaction than other parents whose children had used PCAs (p = 0.008). Although elective penicillin skin testing is useful and safe in the pediatric population, a significant proportion of parents still refuse PCAs even though they are needed. Identification of parents that were very frightened by their children's allergic reactions and additional reassurance could improve this situation.

  9. Monte carlo method-based QSAR modeling of penicillins binding to human serum proteins.

    PubMed

    Veselinović, Jovana B; Toropov, Andrey A; Toropova, Alla P; Nikolić, Goran M; Veselinović, Aleksandar M

    2015-01-01

    The binding of penicillins to human serum proteins was modeled with optimal descriptors based on the Simplified Molecular Input-Line Entry System (SMILES). The concentrations of protein-bound drug for 87 penicillins expressed as percentage of the total plasma concentration were used as experimental data. The Monte Carlo method was used as a computational tool to build up the quantitative structure-activity relationship (QSAR) model for penicillins binding to plasma proteins. One random data split into training, test and validation set was examined. The calculated QSAR model had the following statistical parameters: r(2)  = 0.8760, q(2)  = 0.8665, s = 8.94 for the training set and r(2)  = 0.9812, q(2)  = 0.9753, s = 7.31 for the test set. For the validation set, the statistical parameters were r(2)  = 0.727 and s = 12.52, but after removing the three worst outliers, the statistical parameters improved to r(2)  = 0.921 and s = 7.18. SMILES-based molecular fragments (structural indicators) responsible for the increase and decrease of penicillins binding to plasma proteins were identified. The possibility of using these results for the computer-aided design of new penicillins with desired binding properties is presented.

  10. Absence of cross-reactivity to carbapenems in patients with delayed hypersensitivity to penicillins.

    PubMed

    Romano, A; Gaeta, F; Valluzzi, R L; Alonzi, C; Maggioletti, M; Zaffiro, A; Caruso, C; Quaratino, D

    2013-12-01

    Studies performed on subjects with IgE-mediated hypersensitivity to penicillins have demonstrated a 1% rate of cross-reactivity between penicillins and both imipenem and meropenem, while a single study found a 5.5% rate of cross-reactivity with imipenem/cilastatin in subjects with T-cell-mediated hypersensitivity to β-lactams, mostly penicillins. We studied 204 consecutive subjects with a well-demonstrated T-cell-mediated hypersensitivity to assess the cross-reactivity with carbapenems and the tolerability of such alternative β-lactams. All 204 subjects underwent skin tests with imipenem/cilastatin and meropenem; 130 of them were skin-tested also with ertapenem. Subjects with negative test results were challenged with these carbapenems. All subjects displayed negative skin tests to carbapenems and tolerated challenges. These data demonstrate the absence of clinically significant T-cell-mediated cross-reactivity between penicillins and carbapenems. Negative delayed-reading skin testing with carbapenems in individuals with documented T-cell-mediated hypersensitivity to penicillins correlates well with subsequent clinical tolerance of therapeutic doses of carbapenems.

  11. Lectin characterization of gonococci from an outbreak caused by penicillin-resistant Neisseria gonorrhoeae.

    PubMed Central

    Schalla, W O; Rice, R J; Biddle, J W; Jeanlouis, Y; Larsen, S A; Whittington, W L

    1985-01-01

    A total of 40 Neisseria gonorrhoeae isolates, representing 19 penicillin-resistant isolates (from 8 heterosexual patients and 11 homosexual patients) and 21 penicillin-susceptible isolates (from 15 heterosexual patients and 6 homosexual patients) and obtained from the same geographic area, were examined. Lectin agglutination patterns were based on the reactivity of the isolates with the following 14 lectins: concanavalin A, Lens culinaris, Trichosanthes kinlowii, Griffonia simplicifolia I, Arachis hypogeae (peanut agglutinin), Glycine max (soybean agglutinin), Dolichos bifloris, Griffonia simplicifolia II, Solanum tuberosum (potato starch agglutinin), Triticum vulgaris (wheat germ agglutinin), Limax flavus, Phaseolus vulgaris, Ulex europaeus I, and Lotus tetragonolobus. All isolates were serotyped with monoclonal antibodies specific for gonococcal outer membrane protein I and auxotyped, and the plasmid content was determined. Resistant patient isolates were selected for their decreased penicillin susceptibility, and control isolates were selected for their penicillin susceptibility. Even though the patient isolates demonstrated resistance to penicillin, no phenotypic differences in lectin-grouping patterns were demonstrated between the two study groups; i.e., two predominant lectin groups were observed. No resistance-associated plasmids were detected. All patient isolates were serogroup IB (serovars IB-1, IB-2, and IB-4), whereas 12 of 21 control isolates were serogroup IA (P less than 0.05). Isolates obtained from different anatomical sites in the same patient (cervical and rectal) agreed with regard to lectin patterns and serovars but not auxotypes. PMID:3935658

  12. Effects of erythromycin in combination with penicillin, ampicillin, or gentamicin on the growth of Listeria monocytogenes.

    PubMed Central

    Penn, R L; Ward, T T; Steigbigel, R T

    1982-01-01

    Since the optimal antimicrobial therapy for infections caused by Listeria monocytogenes, particularly in patients allergic to penicillin, is uncertain, we investigated the in vitro effects of erythromycin, alone and in combination with other antibiotics, on listeriae. Seven strains of listeriae were inhibited but not killed by erythromycin, penicillin G, or ampicillin when tested by a microtiter broth dilution method. Susceptibility to gentamicin decreased when tryptose phosphate broth was substituted for Mueller-Hinton broth, but was independent of their calcium and magnesium concentrations. Quantitative killing studies performed with erythromycin combined with either penicillin G or ampicillin yielded antagonism for all strains, in contrast to microtiter checkerboard determinations, which did not indicate antagonism in all instances. Antagonism occurred with strains in both the stationary and log phases of growth and was slightly reversed by a 120-min preincubation of the listeriae with penicillin before the addition of erythromycin. Erythromycin and gentamicin were antagonistic in quantitative killing studies. Based on these in vitro findings, we conclude that the addition of gentamicin to erythromycin offers no advantage in the treatment of listeriosis in the penicillin-allergic patient. PMID:6821458

  13. Fabrication of a highly sensitive penicillin sensor based on charge transfer techniques.

    PubMed

    Lee, Seung-Ro; Rahman, M M; Sawada, Kazuaki; Ishida, Makoto

    2009-03-15

    A highly sensitive penicillin biosensor based on a charge-transfer technique (CTTPS) has been fabricated and demonstrated in this paper. CTTPS comprised a charge accumulation technique for penicilloic acid and H(+) ions perception system. With the proposed CTTPS, it is possible to amplify the sensing signals without external amplifier by using the charge accumulation cycles. The fabricated CTTPS exhibits excellent performance for penicillin detection and exhibit a high-sensitivity (47.852 mV/mM), high signal-to-noise ratio (SNR), large span (1445 mV), wide linear range (0-25 mM), fast response time (<3s), and very good reproducibility. A very lower detection limit of about 0.01 mM was observed from the proposed sensor. Under optimum conditions, the proposed CTTPS outstripped the performance of the widely used ISFET penicillin sensor and exhibited almost eight times greater sensitivity as compared to ISFET (6.56 mV/mM). The sensor system is implemented for the measurement of the penicillin concentration in penicillin fermentation broth. PMID:18977651

  14. Ampicillin/penicillin-binding protein interactions as a model drug-target system to optimize affinity pull-down and mass spectrometric strategies for target and pathway identification.

    PubMed

    von Rechenberg, Moritz; Blake, Brian Kelly; Ho, Yew-Seng J; Zhen, Yuejun; Chepanoske, Cindy Lou; Richardson, Bonnie E; Xu, Nafei; Kery, Vladimir

    2005-05-01

    The identification and validation of the targets of active compounds identified in cell-based assays is an important step in preclinical drug development. New analytical approaches that combine drug affinity pull-down assays with mass spectrometry (MS) could lead to the identification of new targets and druggable pathways. In this work, we investigate a drug-target system consisting of ampicillin- and penicillin-binding proteins (PBPs) to evaluate and compare different amino-reactive resins for the immobilization of the affinity compound and mass spectrometric methods to identify proteins from drug affinity pull-down assays. First, ampicillin was immobilized onto various amino-reactive resins, which were compared in the ampicillin-PBP model with respect to their nonspecific binding of proteins from an Escherichia coli membrane extract. Dynal M-270 magnetic beads were chosen to further study the system as a model for capturing and identifying the targets of ampicillin, PBPs that were specifically and covalently bound to the immobilized ampicillin. The PBPs were identified, after in situ digestion of proteins bound to ampicillin directly on the beads, by using either one-dimensional (1-D) or two-dimensional (2-D) liquid chromatography (LC) separation techniques followed by tandem mass spectrometry (MS/MS) analysis. Alternatively, an elution with N-lauroylsarcosine (sarcosyl) from the ampicillin beads followed by in situ digestion and 2-D LC-MS/MS analysis identified proteins potentially interacting noncovalently with the PBPs or the ampicillin. The in situ approach required only little time, resources, and sample for the analysis. The combination of drug affinity pull-down assays with in situ digestion and 2-D LC-MS/MS analysis is a useful tool in obtaining complex information about a primary drug target as well as its protein interactors. PMID:15761956

  15. Status of plutonium ceramic immobilization processes and immobilization forms

    SciTech Connect

    Ebbinghaus, B.B.; Van Konynenburg, R.A.; Vance, E.R.; Jostsons, A.

    1996-05-01

    Immobilization in a ceramic followed by permanent emplacement in a repository or borehole is one of the alternatives currently being considered by the Fissile Materials Disposition Program for the ultimate disposal of excess weapons-grade plutonium. To make Pu recovery more difficult, radioactive cesium may also be incorporated into the immobilization form. Valuable data are already available for ceramics form R&D efforts to immobilize high-level and mixed wastes. Ceramics have a high capacity for actinides, cesium, and some neutron absorbers. A unique characteristic of ceramics is the existence of mineral analogues found in nature that have demonstrated actinide immobilization over geologic time periods. The ceramic form currently being considered for plutonium disposition is a synthetic rock (SYNROC) material composed primarily of zirconolite (CaZrTi{sub 2}O{sub 7}), the desired actinide host phase, with lesser amounts of hollandite (BaAl{sub 2}Ti{sub 6}O{sub 16}) and rutile (TiO{sub 2}). Alternative actinide host phases are also being considered. These include pyrochlore (Gd{sub 2}Ti{sub 2}O{sub 7}), zircon (ZrSiO{sub 4}), and monazite (CePO{sub 4}), to name a few of the most promising. R&D activities to address important technical issues are discussed. Primarily these include moderate scale hot press fabrications with plutonium, direct loading of PuO{sub 2} powder, cold press and sinter fabrication methods, and immobilization form formulation issues.

  16. Sir Howard Walter Florey--the force behind the development of penicillin.

    PubMed

    Ligon, B Lee

    2004-04-01

    The development of penicillin was a watershed in the battle against infectious diseases. The primary individuals responsible for its discovery and development were Sir Alexander Fleming, Sir Howard Walter Florey, and Ernst B. Chain, now primary figures in the annals of medical history. The individual who serendipitously "discovered" penicillin was Sir Alexander Fleming. Despite the determination displayed by Fleming, little notice was given to his discovery for more than a decade, and the active substance was not isolated. Finally, in 1939, Florey, along with Chain, led a team of British scientists who successfully manufactured the drug from the liquid broth in which penicillin grows. They, along with Fleming, were given the 1945 Nobel Prize in Physiology or Medicine for their roles in the discovery and development of this agent. This biography focuses on the life and work of Sir Howard Walter Florey.

  17. Penicillin's catalytic mechanism revealed by inelastic neutrons and quantum chemical theory.

    PubMed

    Mucsi, Zoltán; Chass, Gregory A; Ábrányi-Balogh, Péter; Jójárt, Balázs; Fang, De-Cai; Ramirez-Cuesta, Annibal J; Viskolcz, Béla; Csizmadia, Imre G

    2013-12-21

    Penicillin, travels through bodily fluids, targeting and acylatively inactivating enzymes responsible for cell-wall synthesis in gram-positive bacteria. Somehow, it avoids metabolic degradation remaining inactive en route. To resolve this ability to switch from a non-active, to a highly reactive form, we investigated the dynamic structure-activity relationship of penicillin by inelastic neutron spectroscopy, reaction kinetics, NMR and multi-scale theoretical modelling (QM/MM and post-HF ab initio). Results show that by a self-activating physiological pH-dependent two-step proton-mediated process, penicillin changes geometry to activate its irreversibly reactive acylation, facilitated by systemic intramolecular energy management and cooperative vibrations. This dynamic mechanism is confirmed by the first ever reported characterisation of an antibiotic by neutrons, achieved on the TOSCA instrument (ISIS facility, RAL, UK).

  18. Preliminary consultation on preferred product characteristics of benzathine penicillin G for secondary prophylaxis of rheumatic fever.

    PubMed

    Wyber, Rosemary; Boyd, Ben J; Colquhoun, Samantha; Currie, Bart J; Engel, Mark; Kado, Joseph; Karthikeyan, Ganesan; Sullivan, Mark; Saxena, Anita; Sheel, Meru; Steer, Andrew; Mucumbitsi, Joseph; Zühlke, Liesl; Carapetis, Jonathan

    2016-10-01

    Rheumatic fever is caused by an abnormal immune reaction to group A streptococcal infection. Secondary prophylaxis with antibiotics is recommended for people after their initial episode of rheumatic fever to prevent recurrent group A streptococcal infections, recurrences of rheumatic fever and progression to rheumatic heart disease. This secondary prophylaxis must be maintained for at least a decade after the last episode of rheumatic fever. Benzathine penicillin G is the first line antibiotic for secondary prophylaxis, delivered intramuscularly every 2 to 4 weeks. However, adherence to recommended secondary prophylaxis regimens is a global challenge. This paper outlines a consultation with global experts in rheumatic heart disease on the characteristics of benzathine penicillin G formulations which could be changed to improve adherence with secondary prophylaxis. Characteristics included dose interval, pain, administration mechanism, cold chain independence and cost. A sample target product profile for reformulated benzathine penicillin G is presented. PMID:27465618

  19. Preliminary consultation on preferred product characteristics of benzathine penicillin G for secondary prophylaxis of rheumatic fever.

    PubMed

    Wyber, Rosemary; Boyd, Ben J; Colquhoun, Samantha; Currie, Bart J; Engel, Mark; Kado, Joseph; Karthikeyan, Ganesan; Sullivan, Mark; Saxena, Anita; Sheel, Meru; Steer, Andrew; Mucumbitsi, Joseph; Zühlke, Liesl; Carapetis, Jonathan

    2016-10-01

    Rheumatic fever is caused by an abnormal immune reaction to group A streptococcal infection. Secondary prophylaxis with antibiotics is recommended for people after their initial episode of rheumatic fever to prevent recurrent group A streptococcal infections, recurrences of rheumatic fever and progression to rheumatic heart disease. This secondary prophylaxis must be maintained for at least a decade after the last episode of rheumatic fever. Benzathine penicillin G is the first line antibiotic for secondary prophylaxis, delivered intramuscularly every 2 to 4 weeks. However, adherence to recommended secondary prophylaxis regimens is a global challenge. This paper outlines a consultation with global experts in rheumatic heart disease on the characteristics of benzathine penicillin G formulations which could be changed to improve adherence with secondary prophylaxis. Characteristics included dose interval, pain, administration mechanism, cold chain independence and cost. A sample target product profile for reformulated benzathine penicillin G is presented.

  20. The effects of treadmill exercise on penicillin-induced epileptiform activity

    PubMed Central

    Tutkun, Erkut; Arslan, Gokhan; Ayyildiz, Mustafa; Agar, Erdal

    2016-01-01

    Introduction The aim of this study was to evaluate the effects of short-, moderate- and long-duration treadmill exercise (15, 30 and 60 min) on the mean frequency and amplitude of penicillin-induced epileptiform activity in rats. Material and methods In this study, 32 rats were assigned to 15, 30, and 60 min running exercise groups and the control group, each consisting of 8 rats. According to the specified protocol, the rats were submitted to running exercises at the same hour of each day for 90 days. After the exercise program, the rats were administered (500 IU/2.5 µl) of penicillin into the left cortex by the microinjection method. An electrocorticogram (ECoG) recording was performed for 3 h using a data acquisition system. The frequency and the amplitude of the recordings were analyzed. Results Short-duration treadmill exercise (15 min) caused a decrease in the frequency of penicillin-induced epileptiform activity at 70 min after penicillin injection (p < 0.001). The mean frequency of epileptiform activity decreased at 90 min after penicillin injection in the 30 and 60 min treadmill exercise groups (p < 0.01). The mean amplitude of epileptiform activity was not changed in any of the exercise groups compared to the control (p > 0.05). Conclusions The results of the present study demonstrate for the first time that short-, moderate- and long-duration treadmill exercises decreased the frequency of penicillin-induced epileptiform activity. These findings may contribute to improving the quality of life in epileptic patients. PMID:27695482

  1. The effects of treadmill exercise on penicillin-induced epileptiform activity

    PubMed Central

    Tutkun, Erkut; Arslan, Gokhan; Ayyildiz, Mustafa; Agar, Erdal

    2016-01-01

    Introduction The aim of this study was to evaluate the effects of short-, moderate- and long-duration treadmill exercise (15, 30 and 60 min) on the mean frequency and amplitude of penicillin-induced epileptiform activity in rats. Material and methods In this study, 32 rats were assigned to 15, 30, and 60 min running exercise groups and the control group, each consisting of 8 rats. According to the specified protocol, the rats were submitted to running exercises at the same hour of each day for 90 days. After the exercise program, the rats were administered (500 IU/2.5 µl) of penicillin into the left cortex by the microinjection method. An electrocorticogram (ECoG) recording was performed for 3 h using a data acquisition system. The frequency and the amplitude of the recordings were analyzed. Results Short-duration treadmill exercise (15 min) caused a decrease in the frequency of penicillin-induced epileptiform activity at 70 min after penicillin injection (p < 0.001). The mean frequency of epileptiform activity decreased at 90 min after penicillin injection in the 30 and 60 min treadmill exercise groups (p < 0.01). The mean amplitude of epileptiform activity was not changed in any of the exercise groups compared to the control (p > 0.05). Conclusions The results of the present study demonstrate for the first time that short-, moderate- and long-duration treadmill exercises decreased the frequency of penicillin-induced epileptiform activity. These findings may contribute to improving the quality of life in epileptic patients.

  2. [Streptococcus pyogenes: penicillin and erythromycin susceptibility in the cities of Neuquen and Cipolletti].

    PubMed

    Soriano, S V; Brasili, S; Saiz, M; Carranza, C; Vidal, P; Calderón, J; Lopardo, H A

    2000-01-01

    Penicillin resistance has not yet been detected in Streptococcus pyogenes. However macrolide-resistant streptococci have emerged in several countries. Only low rates of erythromycin-resistant S. pyogenes were reported in Argentina, with the exception of a 11.1% observed in Mendoza. The aim of the present study was to determine the susceptibility to penicillin and to erythromycin of 251 consecutive clinically-significant isolates of S. pyogenes obtained from four centers of Cipolletti and Neuquén during the period April-December 1998. The double disk test with erythromycin and clindamycin disks was employed as a screening method to detect ERY-resistant streptococci and to determine the phenotype of macrolide resistance. Disk diffusion was also employed for determining penicillin susceptibility. Macrolide-resistant isolates were also tested for penicillin, ceftriaxone, erythromycin, clindamycin and azithromycin susceptibility by the agar dilution method. Additionally they were also tested for erythromycin susceptibility by E-test (AB Biodisk, Solna, Sweden). All streptococci studied were susceptible to penicillin and thirty of them (12.0%) were resistant to erythromycin. All these resistant isolates were also resistant to azithromycin but susceptible to ceftriaxone and clindamycin. They showed the phenotype M (probably efflux-mediated mechanism) and the MICs of erythromycin ranged between 8 and 16 micrograms/ml. According to these results we conclude that in spite of universal susceptibility to penicillin in S. pyogenes, macrolide resistance is a matter of concern in Neuquén and Cipolletti. At least in those cities it appears to be necessary to routinely perform macrolide susceptibility tests in beta-hemolytic streptococci.

  3. Use of microbial beta-lactamase to destroy penicillin added to milk.

    PubMed

    Korycka-Dahl, M; Richardson, T; Bradley, R L

    1985-08-01

    A simple method is described for destruction of penicillin residues in bulk milk to an undetectable amount (less than .003 U/ml) with commercially available crude beta-lactamase enzyme. Milk containing .1 or .5 U/ml penicillin G was treated with .01 to 1.0 mU/ml of beta-lactamase (Bacillus cereus) for up to 96 h. The Bacillus stearothermophilus var. calidolactis assay was used to quantify penicillin in milk between .003 to 1.0 U/ml. The .5 U/ml of penicillin G was reduced to an undetectable amount within 18 h at 4 degrees C by 1.0 mU/ml of beta-lactamase. The development of titratable acidity over 5 to 6 h in contaminated milks treated with beta-lactamase and inoculated with Streptococcus thermophilus GH, Streptococcus cremoris, Streptococcus lactis, or a commercial starter culture was the same as for control milk samples containing no additives or only enzyme. Pilot-scale manufacture of Swiss and Cheddar cheeses from contaminated milks treated with beta-lactamase yielded cheeses of comparable quality, to control cheeses produced from penicillin-free milk. There were no delays in acid production as judged from pH measurements during production and ripening of the cheeses. About 50% of beta-lactamase activity added to milk remained after pasteurization at 63 degrees C for 30 min. The safety for human consumption of cheese containing small quantities of penicillin degradation products from milk treated with beta-lactamase remains to be established.

  4. Lysozyme and Penicillin Inhibit the Growth of Anaerobic Ammonium-Oxidizing Planctomycetes

    PubMed Central

    Hu, Ziye; van Alen, Theo; Jetten, Mike S. M.

    2013-01-01

    Anaerobic ammonium-oxidizing (anammox) planctomycetes oxidize ammonium in the absence of molecular oxygen with nitrite as the electron acceptor. Although planctomycetes are generally assumed to lack peptidoglycan in their cell walls, recent genome data imply that the anammox bacteria have the genes necessary to synthesize peptidoglycan-like cell wall structures. In this study, we investigated the effects of two antibacterial agents that target the integrity and synthesis of peptidoglycan (lysozyme and penicillin G) on the anammox bacterium Kuenenia stuttgartiensis. The effects of these compounds were determined in both short-term batch incubations and long-term (continuous-cultivation) growth experiments in membrane bioreactors. Lysozyme at 1 g/liter (20 mM EDTA) lysed anammox cells in less than 60 min, whereas penicillin G did not have any observable short-term effects on anammox activity. Penicillin G (0.5, 1, and 5 g/liter) reversibly inhibited the growth of anammox bacteria in continuous-culture experiments. Furthermore, transcriptome analyses of the penicillin G-treated reactor and the control reactor revealed that penicillin G treatment resulted in a 10-fold decrease in the ribosome levels of the cells. One of the cell division proteins (Kustd1438) was downregulated 25-fold. Our results suggested that anammox bacteria contain peptidoglycan-like components in their cell wall that can be targeted by lysozyme and penicillin G-sensitive proteins were involved in their synthesis. Finally, we showed that a continuous membrane reactor system with free-living planktonic cells was a very powerful tool to study the physiology of slow-growing microorganisms under physiological conditions. PMID:24096424

  5. Lysozyme and penicillin inhibit the growth of anaerobic ammonium-oxidizing planctomycetes.

    PubMed

    Hu, Ziye; van Alen, Theo; Jetten, Mike S M; Kartal, Boran

    2013-12-01

    Anaerobic ammonium-oxidizing (anammox) planctomycetes oxidize ammonium in the absence of molecular oxygen with nitrite as the electron acceptor. Although planctomycetes are generally assumed to lack peptidoglycan in their cell walls, recent genome data imply that the anammox bacteria have the genes necessary to synthesize peptidoglycan-like cell wall structures. In this study, we investigated the effects of two antibacterial agents that target the integrity and synthesis of peptidoglycan (lysozyme and penicillin G) on the anammox bacterium Kuenenia stuttgartiensis. The effects of these compounds were determined in both short-term batch incubations and long-term (continuous-cultivation) growth experiments in membrane bioreactors. Lysozyme at 1 g/liter (20 mM EDTA) lysed anammox cells in less than 60 min, whereas penicillin G did not have any observable short-term effects on anammox activity. Penicillin G (0.5, 1, and 5 g/liter) reversibly inhibited the growth of anammox bacteria in continuous-culture experiments. Furthermore, transcriptome analyses of the penicillin G-treated reactor and the control reactor revealed that penicillin G treatment resulted in a 10-fold decrease in the ribosome levels of the cells. One of the cell division proteins (Kustd1438) was downregulated 25-fold. Our results suggested that anammox bacteria contain peptidoglycan-like components in their cell wall that can be targeted by lysozyme and penicillin G-sensitive proteins were involved in their synthesis. Finally, we showed that a continuous membrane reactor system with free-living planktonic cells was a very powerful tool to study the physiology of slow-growing microorganisms under physiological conditions. PMID:24096424

  6. Isolation of Neisseria meningitidis strains with increase of penicillin minimal inhibitory concentrations

    PubMed Central

    Sáez-Nieto, J. A.; Fontanals, D.; De Jalon, J. Garcia; De Artola, V. Martinez; Peña, P.; Morera, M. A.; Verdaguer, R.; Sanfeliu, I.; Belio-Blasco, C.; Perez-Saenz, J. L.; Casal, J.

    1987-01-01

    We report the isolation and characterization of ten strains showing an increase in the minimal inhibitory concentrations to penicillin (MICs > 0·1 μg/ml), and describe the epidemiological, clinical and microbiological features. The susceptibility of 3432 meningococcal strains isolated from patients in the recent epidemic wave (1978-86) in Spain, to several antimicrobial agents used in the treatment and chemoprophylaxis of meningococcal infection has been tested. Most were resistant to sulphadiazine but sensitive to other antibiotics. The possible existence of a new pattern of behaviour of meningococcal to penicillin is discussed. PMID:3119361

  7. Large-scale outbreak of infection with Mycobacterium chelonae subsp. abscessus after penicillin injection.

    PubMed

    Zhibang, Yang; BiXia, Zhang; Qishan, Lu; Lihao, Chen; Xiangquan, Liu; Huaping, Li

    2002-07-01

    An outbreak of infection with Mycobacterium chelonae subsp. abscessus after the injection of penicillin in 86 patients attending a factory hospital is reported. The bacterium was isolated both from lids and from the soil where the drug was stored. Molecular analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of whole-cell proteins and plasmids revealed a pattern identical to that of the strains isolated from the wounds. The source of the infections was soil contamination of the vial lids and was caused by improper use and sterilization of penicillin vials. PMID:12089291

  8. HYPERSENSITIVITY TO PENICILLENIC ACID DERIVATIVES IN HUMAN BEINGS WITH PENICILLIN ALLERGY

    PubMed Central

    Parker, Charles W.; Shapiro, Jack; Kern, Milton; Eisen, Herman N.

    1962-01-01

    Multifunctional derivatives of penicillenic acid are effective elicitors of wheal-and-erythema skin responses in humans allergic to penicillin. Of the effective derivatives, penicilloyl-polylysines are particularly attractive as skin test reagents because they appear to be incapable of inducing antibody formation. The skin responses are specifically inhibitable in most instances by homologous unifunctional haptens. The penicillenic acid derivatives which appear to be determinants of human allergic reactions to penicillin are: penicilloyl, penicillenate, and groups of the penamaldate-penilloaldehyde type. Of these, the most significant appears to be the penicilloyl-lysyl determinant. PMID:14483916

  9. Penicillin-susceptible group B streptococcal clinical isolates with reduced cephalosporin susceptibility.

    PubMed

    Nagano, Noriyuki; Nagano, Yukiko; Toyama, Masami; Kimura, Kouji; Shibayama, Keigo; Arakawa, Yoshichika

    2014-09-01

    We characterized penicillin-susceptible group B streptococcal (PSGBS) clinical isolates exhibiting no growth inhibition zone around a ceftibuten disk (CTB(r) PSGBS). The CTB(r) PSGBS isolates, for which augmented MICs of cefaclor and ceftizoxime were found, shared a T394A substitution in penicillin-binding protein 2X (PBP 2X) and a T567I substitution in PBP 2B, together with an additional G429S substitution in PBP 2X or a T145A substitution in PBP 1A, although the T145A substitution in the transglycosidase domain of PBP 1A would have no effect on the level of resistance to ceftibuten.

  10. Burkholderia cepacia endophthalmitis, in a penicillin allergic patient, following a ranibizumab injection.

    PubMed

    Saffra, Norman; Moriarty, Emily

    2014-01-01

    Burkholderia cepacia, a Gram-negative bacterium commonly found in water and soil, is a rare cause of endophthalmitis. The authors report a case of a penicillin-allergic patient who presented 15 days after an uneventful injection of ranibizumab for neovascular age-related macular degeneration with culture-positive B cepacia endophthalmitis. Initial antibiotic therapy using non-penicillin-based medications was not successful in eradicating the bacteria. Subsequent treatment with a third-generation cephalosporin resulted in complete resolution of the infection. B cepacia should be included among the bacterial species that may cause endophthalmitis after intravitreal injections. PMID:24526197

  11. One-Electron Reduction of Penicillins in Relation to the Oxidative Stress Phenomenon.

    PubMed

    Szabó, László; Tóth, Tünde; Takács, Erzsébet; Wojnárovits, László

    2015-12-11

    Certain bactericidal antibiotics target mitochondrial components and, due to the leakage of electrons from the electron transport chain, one-electron reduction might occur that can lead to intermediates passing the electron to suitable acceptors. This study aimed at investigating the one-electron reduction mechanism of selected penicillin derivatives using pulse radiolysis techniques. Penicillins can accommodate the electron on each of their carbonyl carbon. Ketyl radicals are thus produced, which are reducing agents with possibility to interact with suitable biomolecules. A detailed mechanism of the reduction is reported.

  12. One-Electron Reduction of Penicillins in Relation to the Oxidative Stress Phenomenon.

    PubMed

    Szabó, László; Tóth, Tünde; Takács, Erzsébet; Wojnárovits, László

    2015-01-01

    Certain bactericidal antibiotics target mitochondrial components and, due to the leakage of electrons from the electron transport chain, one-electron reduction might occur that can lead to intermediates passing the electron to suitable acceptors. This study aimed at investigating the one-electron reduction mechanism of selected penicillin derivatives using pulse radiolysis techniques. Penicillins can accommodate the electron on each of their carbonyl carbon. Ketyl radicals are thus produced, which are reducing agents with possibility to interact with suitable biomolecules. A detailed mechanism of the reduction is reported. PMID:26690427

  13. Sample stacking for the analysis of eight penicillin antibiotics by micellar electrokinetic capillary chromatography.

    PubMed

    Puig, Patricia; Borrull, Francesc; Calull, Marta; Aguilar, Carme

    2005-02-01

    We studied the use of micellar electrokinetic capillary chromatography for separating eight penicillins. The method consists of (i) an electrophoretic separation based on micellar electrokinetic capillary chromatography, which uses sodium dodecyl sulfate (SDS) as surfactant; (ii) a sample stacking technique called reverse electrode polarity stacking mode (REPSM); and (iii) direct UV detection. The background electrolyte that gave complete separation contained 20 mM sodium borate buffer and 60 mM SDS. The sensitivity of the method was improved by an enrichment step that used on-column stacking. The limits of detection were at the microg.L(-1) level for the penicillins and did not detract from the peak resolution.

  14. Alexander Fleming, citrated blood and penicillin: paths not pursued and applications delayed.

    PubMed

    Mortimer, P P

    2009-12-01

    Ninety years ago Alexander Fleming (later to discover penicillin) jointly wrote a description of the use of indirect transfusions of citrated blood at a World War 1 (WW1) base hospital. It was the longest series yet to be published, incorporating what was then a novel procedure for treating war casualties. Returning to civilian life Fleming, a qualified surgeon and bacteriologist, chose a different career path, and not until the wars of the late 1930s were the advances in transfusion in WW1 fully incorporated into the management of trauma and haemorrhage. Like penicillin, the benefits of indirect transfusion were only slowly realised.

  15. Context-dependent modulation of alphabetagamma and alphabetadelta GABA A receptors by penicillin: implications for phasic and tonic inhibition.

    PubMed

    Feng, Hua-Jun; Botzolakis, Emmanuel J; Macdonald, Robert L

    2009-01-01

    Penicillin, an open-channel blocker of GABA(A) receptors, was recently reported to inhibit phasic, but not tonic, currents in hippocampal neurons. To distinguish between isoform-specific and context-dependent modulation as possible explanations for this selectivity, the effects of penicillin were evaluated on recombinant GABA(A) receptors expressed in HEK293T cells. When co-applied with saturating GABA, penicillin decreased peak amplitude, induced rebound, and prolonged deactivation of currents evoked from both synaptic and extrasynaptic receptor isoforms. However, penicillin had isoform-specific effects on the extent of desensitization, reflecting its ability to differentially modulate peak (non-equilibrium) and residual (near-equilibrium) currents. This suggested that the context of activation could determine the apparent sensitivity of a given receptor isoform to penicillin. To test this hypothesis, we explored the ability of penicillin to modulate synaptic and extrasynaptic isoform currents that were activated under more physiologically relevant conditions. Interestingly, while currents evoked from synaptic isoforms under phasic conditions (transient activation by a saturating concentration of GABA) were substantially inhibited by penicillin, currents evoked from extrasynaptic isoforms under tonic conditions (prolonged application by a sub-saturating concentration of GABA) were minimally affected. We therefore concluded that the reported inability of penicillin to modulate tonic currents could not simply be attributed to insensitivity of extrasynaptic receptors, but rather, reflected an inability to modulate these receptors in their native context of activation.

  16. A microplate assay for the coupled transglycosylase-transpeptidase activity of the penicillin binding proteins; a vancomycin-neutralizing tripeptide combination prevents penicillin inhibition of peptidoglycan synthesis.

    PubMed

    Kumar, Vidya P; Basavannacharya, Chandrakala; de Sousa, Sunita M

    2014-07-18

    A microplate, scintillation proximity assay to measure the coupled transglycosylase-transpeptidase activity of the penicillin binding proteins in Escherichia coli membranes was developed. Membranes were incubated with the two peptidoglycan sugar precursors UDP-N-acetyl muramylpentapeptide (UDP-MurNAc(pp)) and UDP-[(3)H]N-acetylglucosamine in the presence of 40 μM vancomycin to allow in situ accumulation of lipid II. In a second step, vancomycin inhibition was relieved by addition of a tripeptide (Lys-D-ala-D-ala) or UDP-MurNAc(pp), resulting in conversion of lipid II to cross-linked peptidoglycan. Inhibitors of the transglycosylase or transpeptidase were added at step 2. Moenomycin, a transglycosylase inhibitor, had an IC50 of 8 nM. Vancomycin and nisin also inhibited the assay. Surprisingly, the transpeptidase inhibitors penicillin and ampicillin showed no inhibition. In a pathway assay of peptidoglycan synthesis, starting from the UDP linked sugar precursors, inhibition by penicillin was reversed by a 'neutral' combination of vancomycin plus tripeptide, suggesting an interaction thus far unreported. PMID:24944023

  17. A microplate assay for the coupled transglycosylase-transpeptidase activity of the penicillin binding proteins; a vancomycin-neutralizing tripeptide combination prevents penicillin inhibition of peptidoglycan synthesis.

    PubMed

    Kumar, Vidya P; Basavannacharya, Chandrakala; de Sousa, Sunita M

    2014-07-18

    A microplate, scintillation proximity assay to measure the coupled transglycosylase-transpeptidase activity of the penicillin binding proteins in Escherichia coli membranes was developed. Membranes were incubated with the two peptidoglycan sugar precursors UDP-N-acetyl muramylpentapeptide (UDP-MurNAc(pp)) and UDP-[(3)H]N-acetylglucosamine in the presence of 40 μM vancomycin to allow in situ accumulation of lipid II. In a second step, vancomycin inhibition was relieved by addition of a tripeptide (Lys-D-ala-D-ala) or UDP-MurNAc(pp), resulting in conversion of lipid II to cross-linked peptidoglycan. Inhibitors of the transglycosylase or transpeptidase were added at step 2. Moenomycin, a transglycosylase inhibitor, had an IC50 of 8 nM. Vancomycin and nisin also inhibited the assay. Surprisingly, the transpeptidase inhibitors penicillin and ampicillin showed no inhibition. In a pathway assay of peptidoglycan synthesis, starting from the UDP linked sugar precursors, inhibition by penicillin was reversed by a 'neutral' combination of vancomycin plus tripeptide, suggesting an interaction thus far unreported.

  18. The Enterococcus hirae R40 penicillin-binding protein 5 and the methicillin-resistant Staphylococcus aureus penicillin-binding protein 2' are similar.

    PubMed

    el Kharroubi, A; Jacques, P; Piras, G; Van Beeumen, J; Coyette, J; Ghuysen, J M

    1991-12-01

    The penicillin-resistant Enterococcus hirae R40 has a typical profile of membrane-bound penicillin-binding proteins (PBPs) except that the 71 kDa PBP5 of low penicillin affinity represents about 50% of all the PBPs present. Water-soluble tryptic-digest peptides were selectively produced from PBP5, their N-terminal regions were sequenced and synthetic oligonucleotides were used as primers to generate a 476 bp DNA fragment by polymerase chain reaction. On the basis of these data, the PBP5-encoding gene was cloned in Escherichia coli by using pBR322 as vector. The gene, included in a 7.1 kb insert, had the information for a 678-amino acid-residue protein. PBP5 shows similarity, in the primary structure, with the high-molecular-mass PBPs of class B. In particular, amino acid alignment of the enterococcal PBP5 and the methicillin-resistant staphylococcal PBP2' generates scores that are 30, for the N-terminal domains, and 53, for the C-terminal domains, standard deviations above that expected for a run of 20 randomized pairs of proteins having the same amino acid compositions as the two proteins under consideration. PMID:1747121

  19. Selected transuranic waste immobilization systems

    SciTech Connect

    Timmerman, C.L.; Treat, R.L.; Ross, W.A.

    1981-12-01

    Waste contaminated with transuranic (TRU) elements may require treatment prior to final disposal. Pacific Northwest Laboratory has conducted research and development to identify and characterize the wastes; to evaluate the possible immobilization requirements and treatment alternatives; and to develop immobilization process technologies. This paper describes systems that are anticipated to be capable of immobilizing a selected TRU waste stream consisting of a blend of process sludge and incinerator ash. The selected waste streams are based on the waste compositions generated at the Rocky Flats Plant, Golden, Colorado. The specific process and waste forms are: in-can glass melting, borosilicate glass monolith; joule-heated glass melting, borosilicate/aluminosilicate glass monolith; glass marble, borosilicate/aluminosilicate glass marble; basalt glass-ceramic, basalt glass-ceramic monolith; cast cement, cast cement monolith; pressed cement, pressed cement pellet; and cold-pressed sintered ceramic, pressed ceramic pellet.

  20. Long-term effects of penicillin resistance and fitness cost on pneumococcal transmission dynamics in a developed setting

    PubMed Central

    Tilevik, Diana

    2016-01-01

    Background The increasing prevalence of penicillin non-susceptible pneumococci (PNSP) throughout the world threatens successful treatment of infections caused by this important bacterial pathogen. The rate at which PNSP clones spread in the community is thought to mainly be determined by two key determinants; the volume of penicillin use and the magnitude of the fitness cost in the absence of treatment. The aim of the study was to determine the impacts of penicillin consumption and fitness cost on pneumococcal transmission dynamics in a developed country setting. Methods An individual-based network model based on real-life demographic data was constructed and applied in a developed country setting (Sweden). A population structure with transmission of carriage taking place within relevant mixing groups, i.e. families, day care groups, school classes, and other close contacts, was considered to properly assess the transmission dynamics for susceptible and PNSP clones. Several scenarios were simulated and model outcomes were statistically analysed. Results Model simulations predicted that with an outpatient penicillin use corresponding to the sales in Sweden 2010 (118 recipes per 1,000 inhabitants per year), the magnitude of a fitness cost for resistance must be at least 5% to offset the advantage of penicillin resistance. Moreover, even if there is a fitness cost associated with penicillin resistance, a considerable reduction of penicillin usage appears to be required to significantly decrease the incidence of PNSP in a community. Conclusion The frequency of PNSP clones is hard to reverse by simply reducing the penicillin consumption even if there is a biological cost associated with resistance. However, because penicillin usage does promote further spread of PNSP clones, it is important to keep down penicillin consumption considering future resistance problems. PMID:27206408

  1. Production of phenolics by immobilized cells of the lichen Pseudevernia furfuracea: the role of epiphytic bacteria.

    PubMed

    Blanch, M; Blanco, Y; Fontaniella, B; Legaz, M E; Vicente, C

    2001-06-01

    Immobilized lichen cells from the thalli of the lichen Pseudevernia furfuracea, supplied with acetate as the only source of carbon, continuously produced phenolic substances, atranorin and physodic acid, over 23 days. Epiphytic bacteria associated with the lichen thallus grew actively, probably using both acetate and reduced compounds supplied by lichen cells, since their active growth was avoided by including 10 microM 3,3'-dichlorophenyl-1,1'dimethylurea in the bath solution. Penicillin largely impeded the growth of epiphytic bacteria and decreased phenolic production, which was recovered only at the end of the experimental period, just when the bacteria started a slow, but active growth. We suggest the cooperation of epiphytic bacteria in the biosynthesis of both atranotrin and physodic acid. PMID:11770830

  2. Depletion of penicillin G residues in heavy sows after intramuscular injection. Part I: Tissue residue depletion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Heavy sows (n=126) were treated with penicillin G procaine at a 5x label dose (33,000 IU/kg) for 3 consecutive days by intramuscular (IM) injection using 3 separate patterns (treatments) of drug administration (42 sows per treatment). Treatments differed by pattern and maximum injection volume per s...

  3. Penicillin Use in Meningococcal Disease Management: Active Bacterial Core Surveillance Sites, 2009

    PubMed Central

    Blain, Amy E.; Mandal, Sema; Wu, Henry; MacNeil, Jessica R.; Harrison, Lee H.; Farley, Monica M.; Lynfield, Ruth; Miller, Lisa; Nichols, Megin; Petit, Sue; Reingold, Arthur; Schaffner, William; Thomas, Ann; Zansky, Shelley M.; Anderson, Raydel; Harcourt, Brian H.; Mayer, Leonard W.; Clark, Thomas A.; Cohn, Amanda C.

    2016-01-01

    In 2009, in the Active Bacterial Core surveillance sites, penicillin was not commonly used to treat meningococcal disease. This is likely because of inconsistent availability of antimicrobial susceptibility testing and ease of use of third-generation cephalosporins. Consideration of current practices may inform future meningococcal disease management guidelines. PMID:27704009

  4. From Petroleum to Penicillin. The First Hundred Years of Modern Chemical Engineering: 1859-1959.

    ERIC Educational Resources Information Center

    Burnett, J. N.

    1986-01-01

    Presents a description of the course "From Petroleum to Penicillin" which examines chemical engineering and the chemical industry from a scientific, social and symbolic view. Explains the goals, organization, and requirements of the course. Lists case study and lecture topics. (ML)

  5. Computing the various pathways of penicillin synthesis and their molar yields.

    PubMed

    Prauße, Maria T E; Schäuble, Sascha; Guthke, Reinhard; Schuster, Stefan

    2016-01-01

    More than 80 years after its discovery, penicillin is still a widely used and commercially highly important antibiotic. Here, we analyse the metabolic network of penicillin synthesis in Penicillium chrysogenum based on the concept of elementary flux modes. In particular, we consider the synthesis of the invariant molecular core of the various subtypes of penicillin and the two major ways of incorporating sulfur: transsulfuration and direct sulfhydrylation. 66 elementary modes producing this invariant core are obtained. These show four different yields with respect to glucose, notably ½, 2/5, 1/3, and 2/7, with the highest yield of ½ occurring only when direct sulfhydrylation is used and α-aminoadipate is completely recycled. In the case of no recycling of this intermediate, we find the maximum yield to be 2/7. We compare these values with earlier literature values. Our analysis provides a systematic overview of the redundancy in penicillin synthesis and a detailed insight into the corresponding routes. Moreover, we derive suggestions for potential knockouts that could increase the average yield.

  6. Yeast HXK2 gene reverts glucose regulation mutation of penicillin biosynthesis in P. chrysogenum.

    PubMed

    Pérez, Edmundo A; Fernández, Francisco J; Fierro, Francisco; Mejía, Armando; Marcos, Ana T; Martín, Juan F; Barrios-González, Javier

    2014-01-01

    The mutant Penicillium chrysogenum strain dogR5, derived from strain AS-P-78, does not respond to glucose regulation of penicillin biosynthesis and β-galactosidase, and is partially deficient in D-glucose phosphorilating activity. We have transformed strain dogR5 with the (hexokinase) hxk2 gene from Saccharomyces cerevisiae. Transformants recovered glucose control of penicillin biosynthesis in different degrees, and acquired a hexokinase (fructose phosphorylating) activity absent in strains AS- P-78 and dogR5. Interestingly, they also recovered glucose regulation of β-galactosidase. On the other hand, glucokinase activity was affected in different ways in the transformants; one of which showed a lower activity than the parental dogR5, but normal glucose regulation of penicillin biosynthesis. Our results show that Penicillium chrysogenum AS-P-78 and dogR5 strains lack hexokinase, and suggest that an enzyme with glucokinase activity is involved in glucose regulation of penicillin biosynthesis and β-galactosidase, thus signaling glucose in both primary and secondary metabolism; however, catalytic and signaling activities seem to be independent.

  7. Enhanced pharmacological activity of vitamin B₁₂ and penicillin as nanoparticles.

    PubMed

    Yariv, Inbar; Lipovsky, Anat; Gedanken, Aharon; Lubart, Rachel; Fixler, Dror

    2015-01-01

    Sonochemistry has become a well-known technique for fabricating nanomaterials. Since one of the advantages of nanomaterials is that they have higher chemical activities compared with particles in the bulk form, efforts are being made to produce nano organic compounds with enhanced biological activities that could be exploited in the medical area. This study uses the sonication technique to prepare nano Vitamin B12 and nano Penicillin, and demonstrates their enhanced biological and pharmacological activity. The size and morphology of the nano Penicillin and nano Vitamin B12 were investigated using electron microscopy as well as dynamic light scattering techniques. The sizes of Penicillin and Vitamin B12 nanoparticles (NPs) were found to be 70 and 120-180 nm, respectively. The bactericidal effect of nano Penicillin was studied and found to be higher than that of the bulk form. Reducing the size of Vitamin B12 resulted in their enhanced antioxidative activity as observed using the electron paramagnetic spectroscopy technique. The penetration depth of these organic NPs can be detected by an optical iterative method. It is believed that nano organic drugs fabrication will have a great impact on the medical field.

  8. 21 CFR 520.1696c - Penicillin V potassium for oral solution.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Penicillin V potassium for oral solution. 520.1696c Section 520.1696c Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... chapter. (c) National Academy of Sciences/National Research Council (NAS/NRC) status. The conditions...

  9. 21 CFR 520.1696c - Penicillin V potassium for oral solution.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Penicillin V potassium for oral solution. 520.1696c Section 520.1696c Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... chapter. (c) National Academy of Sciences/National Research Council (NAS/NRC) status. The conditions...

  10. 21 CFR 522.1696c - Penicillin G procaine in oil.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Penicillin G procaine in oil. 522.1696c Section 522.1696c Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... chapter. (c) National Academy of Sciences/National Research Council (NAS/NRC) status. The conditions...

  11. 21 CFR 522.1696c - Penicillin G procaine in oil.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Penicillin G procaine in oil. 522.1696c Section 522.1696c Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... chapter. (c) National Academy of Sciences/National Research Council (NAS/NRC) status. The conditions...

  12. Yeast HXK2 gene reverts glucose regulation mutation of penicillin biosynthesis in P. chrysogenum

    PubMed Central

    Pérez, Edmundo A.; Fernández, Francisco J.; Fierro, Francisco; Mejía, Armando; Marcos, Ana T.; Martín, Juan F.; Barrios-González, Javier

    2014-01-01

    The mutant Penicillium chrysogenum strain dogR5, derived from strain AS-P-78, does not respond to glucose regulation of penicillin biosynthesis and β-galactosidase, and is partially deficient in D-glucose phosphorilating activity. We have transformed strain dogR5 with the (hexokinase) hxk2 gene from Saccharomyces cerevisiae. Transformants recovered glucose control of penicillin biosynthesis in different degrees, and acquired a hexokinase (fructose phosphorylating) activity absent in strains AS- P-78 and dogR5. Interestingly, they also recovered glucose regulation of β-galactosidase. On the other hand, glucokinase activity was affected in different ways in the transformants; one of which showed a lower activity than the parental dogR5, but normal glucose regulation of penicillin biosynthesis. Our results show that Penicillium chrysogenum AS-P-78 and dogR5 strains lack hexokinase, and suggest that an enzyme with glucokinase activity is involved in glucose regulation of penicillin biosynthesis and β-galactosidase, thus signaling glucose in both primary and secondary metabolism; however, catalytic and signaling activities seem to be independent. PMID:25477921

  13. Penicillium chrysogenum Takes up the Penicillin G Precursor Phenylacetic Acid by Passive Diffusion

    PubMed Central

    Hillenga, D. J.; Versantvoort, H.; van der Molen, S.; Driessen, A.; Konings, W. N.

    1995-01-01

    Penicillium chrysogenum utilizes phenylacetic acid as a side chain precursor in penicillin G biosynthesis. During industrial production of penicillin G, phenylacetic acid is fed in small amounts to the medium to avoid toxic side effects. Phenylacetic acid is taken up from the medium and intracellularly coupled to 6-aminopenicillanic acid. To enter the fungal cell, phenylacetic acid has to pass the plasma membrane. The process via which phenylacetic acid crosses the plasma membrane was studied in mycelia and liposomes. Uptake of phenylacetic acid by mycelium was nonsaturable, and the initial velocity increased logarithmically with decreasing external pH. Studies with liposomes demonstrated a rapid passive flux of the protonated species through liposomal membranes. These results indicate that phenylacetic acid passes the plasma membrane via passive diffusion of the protonated species. The rate of phenylacetic acid uptake at an external concentration of 3 mM is at least 200-fold higher than the penicillin production rate in the Panlabs P2 strain. In this strain, uptake of phenylacetic acid is not the rate-limiting step in penicillin G biosynthesis. PMID:16535072

  14. Enhanced pharmacological activity of Vitamin B12 and Penicillin as nanoparticles

    PubMed Central

    Yariv, Inbar; Lipovsky, Anat; Gedanken, Aharon; Lubart, Rachel; Fixler, Dror

    2015-01-01

    Sonochemistry has become a well-known technique for fabricating nanomaterials. Since one of the advantages of nanomaterials is that they have higher chemical activities compared with particles in the bulk form, efforts are being made to produce nano organic compounds with enhanced biological activities that could be exploited in the medical area. This study uses the sonication technique to prepare nano Vitamin B12 and nano Penicillin, and demonstrates their enhanced biological and pharmacological activity. The size and morphology of the nano Penicillin and nano Vitamin B12 were investigated using electron microscopy as well as dynamic light scattering techniques. The sizes of Penicillin and Vitamin B12 nanoparticles (NPs) were found to be 70 and 120–180 nm, respectively. The bactericidal effect of nano Penicillin was studied and found to be higher than that of the bulk form. Reducing the size of Vitamin B12 resulted in their enhanced antioxidative activity as observed using the electron paramagnetic spectroscopy technique. The penetration depth of these organic NPs can be detected by an optical iterative method. It is believed that nano organic drugs fabrication will have a great impact on the medical field. PMID:26028970

  15. 21 CFR 524.1484h - Neomycin, penicillin, polymyxin, hydrocortisone suspension.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... suspension. 524.1484h Section 524.1484h Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS OPHTHALMIC AND TOPICAL DOSAGE FORM... shall state: This medication contains penicillin. Allergic reactions in humans are known to occur...

  16. 21 CFR 524.1484h - Neomycin, penicillin, polymyxin, hydrocortisone suspension.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... suspension. 524.1484h Section 524.1484h Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS OPHTHALMIC AND TOPICAL DOSAGE FORM... shall state: This medication contains penicillin. Allergic reactions in humans are known to occur...

  17. Practical Disk Diffusion Test for Detecting Group B Streptococcus with Reduced Penicillin Susceptibility▿

    PubMed Central

    Kimura, Kouji; Wachino, Jun-ichi; Kurokawa, Hiroshi; Suzuki, Satowa; Yamane, Kunikazu; Shibata, Naohiro; Arakawa, Yoshichika

    2009-01-01

    Although group B streptococcus (GBS) has been considered to be uniformly susceptible to β-lactams, the presence of GBS with reduced penicillin susceptibility (PRGBS) was recently confirmed genetically. We developed a feasible and reliable method for screening PRGBS in clinical microbiology laboratories using a combination of ceftibuten, oxacillin, and ceftizoxime disks. PMID:19812274

  18. Safety of Benzathine Penicillin for Preventing Congenital Syphilis: A Systematic Review

    PubMed Central

    Galvao, Tais F.; Silva, Marcus T.; Serruya, Suzanne J.; Newman, Lori M.; Klausner, Jeffrey D.; Pereira, Mauricio G.; Fescina, Ricardo

    2013-01-01

    Objective To estimate the risk of serious adverse reactions to benzathine penicillin in pregnant women for preventing congenital syphilis. Methods We searched for clinical trials or cohorts that assessed the incidence of serious adverse reactions to benzathine penicillin in pregnant women and the general population (indirect evidence). MEDLINE, EMBASE, Scopus and other databases were searched up to December 2012. The GRADE approach was used to assess quality of evidence. Absolute risks of each study were calculated along with their 95% confidence intervals (95% CI). We employed the DerSimonian and Laird random effects model in the meta-analyses. Results From 2,765 retrieved studies we included 13, representing 3,466,780 patients. The studies that included pregnant women were conducted to demonstrate the effectiveness of benzathine penicillin: no serious adverse reactions were reported among the 1,244 pregnant women included. In the general population, among 2,028,982 patients treated, 4 died from an adverse reaction. The pooled risk of death was virtually zero. Fifty-four cases of anaphylaxis were reported (pooled absolute risk = 0.002%; 95% CI: 0%–0.003% I2 = 12%). From that estimate, penicillin treatment would be expected to result in an incidence of 0 to 3 cases of anaphylaxis per 100,000 treated. Any adverse reactions were reported in 6,377 patients among 3,465,322 treated with penicillin (pooled absolute risk = 0.169%; 95% CI: 0.073%–0.265% I2 = 97%). The quality of evidence was very low. Conclusion Studies that assessed the risk of serious adverse events due to benzathine penicillin treatment in pregnant women were scarce, but no reports of adverse reactions were found. The incidence of severe adverse outcomes was very low in the general population. The risk of treating pregnant women with benzathine penicillin to prevent congenital syphilis appears very low and does not outweigh its benefits. Further research is needed to improve the

  19. Radiation immobilization of catalase and its application

    NASA Astrophysics Data System (ADS)

    Guanghui, Wang; Hongfei, Ha; Xia, Wang; Jilan, Wu

    Catalase was immobilized by chemical method on porous polyacrylamide particles which produced through radiation polymerization of acrylamide monomer at low temperature (-78°C). Activity of immobilized catalase was enhanced distinctly by joining a chemical "arm" to the support. The method of recovery of catalase activity on immobilized polymer was found by soaking it in certain buffer. The treatment of H 2O 2 both in aqueous solution and alcoholic solution by using the immobilized catalase was performed.

  20. Prelude to rational scale-up of penicillin production: a scale-down study.

    PubMed

    Wang, Guan; Chu, Ju; Noorman, Henk; Xia, Jianye; Tang, Wenjun; Zhuang, Yingping; Zhang, Siliang

    2014-03-01

    Penicillin is one of the best known pharmaceuticals and is also an important member of the β-lactam antibiotics. Over the years, ambitious yields, titers, productivities, and low costs in the production of the β-lactam antibiotics have been stepwise realized through successive rounds of strain improvement and process optimization. Penicillium chrysogenum was proven to be an ideal cell factory for the production of penicillin, and successful approaches were exploited to elevate the production titer. However, the industrial production of penicillin faces the serious challenge that environmental gradients, which are caused by insufficient mixing and mass transfer limitations, exert a considerably negative impact on the ultimate productivity and yield. Scale-down studies regarding diverse environmental gradients have been carried out on bacteria, yeasts, and filamentous fungi as well as animal cells. In accordance, a variety of scale-down devices combined with fast sampling and quenching protocols have been established to acquire the true snapshots of the perturbed cellular conditions. The perturbed metabolome information stemming from scale-down studies contributed to the comprehension of the production process and the identification of improvement approaches. However, little is known about the influence of the flow field and the mechanisms of intracellular metabolism. Consequently, it is still rather difficult to realize a fully rational scale-up. In the future, developing a computer framework to simulate the flow field of the large-scale fermenters is highly recommended. Furthermore, a metabolically structured kinetic model directly related to the production of penicillin will be further coupled to the fluid flow dynamics. A mathematical model including the information from both computational fluid dynamics and chemical reaction dynamics will then be established for the prediction of detailed information over the entire period of the fermentation process and

  1. Novel Penicillin Analogues as Potential Antimicrobial Agents; Design, Synthesis and Docking Studies.

    PubMed

    Ashraf, Zaman; Bais, Abdul; Manir, Md Maniruzzaman; Niazi, Umar

    2015-01-01

    A number of penicillin derivatives (4a-h) were synthesized by the condensation of 6-amino penicillinic acid (6-APA) with non-steroidal anti-inflammatory drugs as antimicrobial agents. In silico docking study of these analogues was performed against Penicillin Binding Protein (PDBID 1CEF) using AutoDock Tools 1.5.6 in order to investigate the antimicrobial data on structural basis. Penicillin binding proteins function as either transpeptidases or carboxypeptidases and in few cases demonstrate transglycosylase activity in bacteria. The excellent antibacterial potential was depicted by compounds 4c and 4e against Escherichia coli, Staphylococcus epidermidus and Staphylococcus aureus compared to the standard amoxicillin. The most potent penicillin derivative 4e exhibited same activity as standard amoxicillin against S. aureus. In the enzyme inhibitory assay the compound 4e inhibited E. coli MurC with an IC50 value of 12.5 μM. The docking scores of these compounds 4c and 4e also verified their greater antibacterial potential. The results verified the importance of side chain functionalities along with the presence of central penam nucleus. The binding affinities calculated from docking results expressed in the form of binding energies ranges from -7.8 to -9.2kcal/mol. The carboxylic group of penam nucleus in all these compounds is responsible for strong binding with receptor protein with the bond length ranges from 3.4 to 4.4 Ǻ. The results of present work ratify that derivatives 4c and 4e may serve as a structural template for the design and development of potent antimicrobial agents.

  2. Novel Penicillin Analogues as Potential Antimicrobial Agents; Design, Synthesis and Docking Studies

    PubMed Central

    Ashraf, Zaman; Bais, Abdul; Manir, Md. Maniruzzaman; Niazi, Umar

    2015-01-01

    A number of penicillin derivatives (4a-h) were synthesized by the condensation of 6-amino penicillinic acid (6-APA) with non-steroidal anti-inflammatory drugs as antimicrobial agents. In silico docking study of these analogues was performed against Penicillin Binding Protein (PDBID 1CEF) using AutoDock Tools 1.5.6 in order to investigate the antimicrobial data on structural basis. Penicillin binding proteins function as either transpeptidases or carboxypeptidases and in few cases demonstrate transglycosylase activity in bacteria. The excellent antibacterial potential was depicted by compounds 4c and 4e against Escherichia coli, Staphylococcus epidermidus and Staphylococcus aureus compared to the standard amoxicillin. The most potent penicillin derivative 4e exhibited same activity as standard amoxicillin against S. aureus. In the enzyme inhibitory assay the compound 4e inhibited E. coli MurC with an IC50 value of 12.5 μM. The docking scores of these compounds 4c and 4e also verified their greater antibacterial potential. The results verified the importance of side chain functionalities along with the presence of central penam nucleus. The binding affinities calculated from docking results expressed in the form of binding energies ranges from -7.8 to -9.2kcal/mol. The carboxylic group of penam nucleus in all these compounds is responsible for strong binding with receptor protein with the bond length ranges from 3.4 to 4.4 Ǻ. The results of present work ratify that derivatives 4c and 4e may serve as a structural template for the design and development of potent antimicrobial agents. PMID:26267242

  3. Implementation of an Infectious Disease Fellow-Managed Penicillin Allergy Skin Testing Service

    PubMed Central

    Heil, Emily L.; Bork, Jacqueline T.; Schmalzle, Sarah A.; Kleinberg, Michael; Kewalramani, Anupama; Gilliam, Bruce L.; Buchwald, Ulrike K.

    2016-01-01

    Background. A large percentage of patients presenting to acute care facilities report penicillin allergies that are associated with suboptimal antibiotic therapy. Penicillin skin testing (PST) can clarify allergy histories but is often limited by access to testing. We aimed to implement an infectious diseases (ID) fellow-managed PST program and to assess the need for PST via national survey. Methods. We conducted a prospective observational study of the implementation of an ID fellow-managed penicillin allergy skin testing service. The primary outcome of the study was to assess the feasibility and acceptability of an ID fellow-managed PST service and its impact on the optimization of antibiotic selection. In addition, a survey of PST practices was sent out to all ID fellowship program directors in the United States. Results. In the first 11 months of the program, 90 patients were assessed for PST and 76 patients were tested. Of the valid tests, 96% were negative, and 84% with a negative test had antibiotic changes; 63% received a narrower spectrum antibiotic, 80% received more effective therapy, and 61% received more cost-effective therapy. The majority of survey of respondents (n = 50) indicated that overreporting of penicillin allergy is a problem in their practice that affects antibiotic selection but listed inadequate personnel and time as the main barriers to PST. Conclusions. Inpatient PST can be successfully managed by ID fellows, thereby promoting optimal antibiotic use in patients reporting penicillin allergies. This model can increase access to PST at institutions without adequate access to allergists while also providing an important educational experience to ID trainees. PMID:27704011

  4. Fan-shaped ejections of regularly arranged murosomes involved in penicillin-induced death of staphylococci.

    PubMed Central

    Giesbrecht, P; Kersten, T; Wecke, J

    1992-01-01

    Electron microscopic research into the murosomes of staphylococci has shown that the number of murosomes involved in penicillin-induced death varies depending on the experimental conditions employed. With 0.1 micrograms of penicillin G per ml, only 1 of a total of about 20 murosomes, the "killing murosome," completely perforated the pressure-stabilized peripheral cell wall during a three-step process. This strictly localized event was mainly attributed to a mechanical effect being comparable to the process of aneurysm formation. Wall perforation was also considered to mark the very moment of penicillin-induced death ("nonlytic killing event"), while bacteriolysis started only postmortem. By varying the osmolarity of the growth medium, the number of murosomes involved in penicillin-induced killing increased considerably, which resulted in the ejection of a fan-shaped row of murosomes at the second division plane. These data are compatible with the finding that, in untreated or chloramphenicol-treated staphylococci, the activation of the murosomes resulted in (i) the formation of regularly arranged "blebs" on the cell surface, containing traces of disintegrated wall material, and (ii) the subsequent liberation of the murosomes lying underneath, leaving behind their former sites in the peripheral wall as a row of regularly arranged "pores" in every division plane. The number, distribution, and positioning of these blebs corresponded with those of the pores and the original murosomes. The significance of wall autolysins liberated from the first division plane for penicillin-induced wall perforation at the second division plane is discussed. Images PMID:1551845

  5. Bacterial sensors based on biosilica immobilization for label-free OWLS detection.

    PubMed

    Adányi, Nóra; Bori, Zsuzsanna; Szendrő, István; Erdélyi, Katalin; Wang, Xiaohong; Schröder, Heinz C; Müller, Werner E G

    2013-06-25

    In the last years, a new group of enzymes, the so-called silicateins, have been identified and characterized, which form the axial filaments of the spicules of the siliceous sponges, consisting of not only amorphous silica among others. These enzymes are able to catalyze the polycondensation and deposition of silica at mild conditions. Silicateins can be expressed in Escherichia coli. The recombinant proteins are expressed on the surface of the cell wall and are able to catalyze the formation of a polysilicate net around the bacterial cells providing the possibility for further attachment to the surface of SiO2 containing sensor chips. With this mild immobilization process it is now possible to prepare novel microbial sensors based on Optical Waveguide Lightmode Spectroscopy. In the present study, the immobilization of silicatein modified E. coli BL21AI cells onto the SiO2-type chips was optimized (buffer concentration, pH, temperature, reaction time, and so on) and then the biological properties, in particular the inhibitory effect of stressors/environmental pollutants on the novel bacterial sensor were studied in real time. The effect of oxidative stress was investigated by exposing the sensors containing biosilica-immobilized E. coli BL21AI cells to various concentrations of hydrogen peroxide. The effect of antibiotics was tested using chloramphenicol (CAP) which is effective against a variety of Gram-positive and Gram-negative bacteria and penicillin G which destroys the bacterial cell wall. In addition, the inhibition by carbofuran (CF) pesticide was also tested. CF is a highly toxic compound which inhibits cholinesterase activity. According our results we can conclude that the novel bacterial sensor consisting of the silicatein modified E. coli BL21AI cells immobilized on OWLS sensor surface could be an effective tool to detect the presence of different type of pollutants in real time measurement. However penicillin G and CF are not specifically inhibitors of

  6. [Activity of cefpodoxime and other oral beta-lactams against Haemophilus influenzae and Streptococcus pneumoniae with different susceptibilities to penicillin].

    PubMed

    Fenoll, A; Robledo, O; Lerma, M; Giménez, M J; Cebrián, L; Casal, J; Aguilar, L; Gómez-Lus, M L

    2006-03-01

    This study explores the influence on the intrinsic activity of different oral beta-lactams of beta-lactamase production in Haemophilus influenzae and penicillin resistance in Streptococcus pneumoniae. Three substudies were performed: a) a general susceptibility study, analyzing 550 strains received by the Spanish Laboratorio de Referencia de Neumococos throughout February and March 2005; b) a study on the influence of penicillin resistance on the activity of beta-lactams, analyzing 251 penicillin-susceptible strains (MICpenicillin intermediate-resistant strains (MIC 0.12-1 mg/l) and 139 penicillin-resistant strains (MIC>or=2 mg/l) randomly chosen among those received by the Spanish Laboratorio de Referencia de Neumococos throughout 2005; and c) an H. influenzae susceptibility study analyzing 150 strains received by Instituto Valenciano de Microbiologia throughout 2005. A total of 71% of S. pneumoniae strains were susceptible to penicillin, 21% exhibited intermediate resistance and 8% strains presented full resistance. H. influenzae beta-lactamase production rate was 18.6%. Of the non-beta-lactamase-producing strains, 3% were not susceptible to ampicillin. Cefpodoxime and cefixime exhibited the highest intrinsic activity against H. influenzae, while amoxicillin and cefpodoxime were the most active compounds against S. pneumoniae. All H. influenzae strains were susceptible to oral cephalosporins and amoxicillin/clavulanic acid. The increase in penicillin resistance in S. pneumoniae influenced cefixime, cefaclor and cefuroxime to a higher degree than amoxicillin and cefpodoxime.

  7. Recent developments and applications of immobilized laccase.

    PubMed

    Fernández-Fernández, María; Sanromán, M Ángeles; Moldes, Diego

    2013-12-01

    Laccase is a promising biocatalyst with many possible applications, including bioremediation, chemical synthesis, biobleaching of paper pulp, biosensing, textile finishing and wine stabilization. The immobilization of enzymes offers several improvements for enzyme applications because the storage and operational stabilities are frequently enhanced. Moreover, the reusability of immobilized enzymes represents a great advantage compared with free enzymes. In this work, we discuss the different methodologies of enzyme immobilization that have been reported for laccases, such as adsorption, entrapment, encapsulation, covalent binding and self-immobilization. The applications of laccase immobilized by the aforementioned methodologies are presented, paying special attention to recent approaches regarding environmental applications and electrobiochemistry.

  8. Immobilization of Heparin: Approaches and Applications

    PubMed Central

    Murugesan, Saravanababu; Xie, Jin; Linhardt, Robert J.

    2014-01-01

    Heparin, an anticoagulant, has been used in many forms to treat various diseases. These forms include soluble heparin and heparin immobilized to supporting matrices by physical adsorption, by covalent chemical methods and by photochemical attachment. These immobilization methods often require the use of spacers or linkers. This review examines and compares various techniques that have been used for the immobilization of heparin as well as applications of these immobilized heparins. In the applications reviewed, immobilized heparin is compared with soluble heparin for efficient and versatile use in each of the various applications. PMID:18289079

  9. Amplification of an MFS transporter encoding gene penT significantly stimulates penicillin production and enhances the sensitivity of Penicillium chrysogenum to phenylacetic acid.

    PubMed

    Yang, Jing; Xu, Xinxin; Liu, Gang

    2012-11-20

    Penicillin is historically important as the first discovered drug against bacterial infections in human. Although the penicillin biosynthetic pathway and regulatory mechanism have been well studied in Penicillium chrysogenum, the compartmentation and molecular transport of penicillin or its precursors are still poorly understood. In search of the genomic database, more than 830 open reading frames (ORFs) were found to encode transmembrane proteins of P. chrysogenum. In order to investigate their roles on penicillin production, one of them (penT) was selected and cloned. The deduced protein of penT belongs to the major facilitator superfamily (MFS) and contains 12 transmembrane spanning domains (TMS). During fermentation, the transcription of penT was greatly induced by penicillin precursors phenylacetic acid (PAA) and phenoxyacetic acid (POA). Knock-down of penT resulted in significant decrease of penicillin production, while over-expression of penT under the promoter of trpC enhanced the penicillin production. Introduction of an additional penT in the wild-type strain of P. chrysogenum doubled the penicillin production and enhanced the sensitivity of P. chrysogenum to the penicillin precursors PAA or POA. These results indicate that penT stimulates penicillin production probably through enhancing the translocation of penicillin precursors across fungal cellular membrane.

  10. A mutant of Escherichia coli defective in penicillin-binding protein 5 and lacking D-alanine carboxypeptidase IA.

    PubMed Central

    Nishimura, Y; Suzuki, H; Hirota, Y; Park, J T

    1980-01-01

    A mutant of Escherichia coli defective in penicillin-binding protein 5 activity was isolated. The mutation (pfv) was shown to be located at 14.0 min on the E. coli chromosome map. Loss of penicillin-binding protein 5 in the pfv mutant was associated with the loss of D-alanine carboxypeptidase IA activity and increased sensitivity to beta-lactam antibiotics. We conclude that penicillin-binding protein 5 catalyzes the major D-alanine carboxypeptidase IA activity and that the enzyme activity, in vivo, protects E. coli cells from killing by low inhibitory concentrations of beta-lactam antibiotics. PMID:6995448

  11. Antimicrobial Activity of Penicillin G and N-acetylcystein on Planktonic and Sessile Cells of Streptococcus suis.

    PubMed

    Espinosa, Ivette; Báez, Michel; Lobo, Evelyn; Martínez, Siomara; Gottschalk, Marcelo

    2016-01-01

    The aim of this study was to investigate the capacity of Streptococcus suis strains to form biofilms and to evaluate the antimicrobial activity of Penicillin G and N-acetylcystein (NAC) on both S. suis sessile and planktonic forms. Only non-typeable isolates of S. suis were correlated with a greater biofilm formation capacity. The MCI of Penicillin G and NAC required for inhibiting biofilm growth were higher than the required concentration for inhibiting planktonic growth. The combinations of NAC and Penicillin G showed a strong synergistic activity that inhibited biofilm formation and disrupted the pre-formed biofilm of S. suis. PMID:27282001

  12. Biodiesel production with immobilized lipase: A review.

    PubMed

    Tan, Tianwei; Lu, Jike; Nie, Kaili; Deng, Li; Wang, Fang

    2010-01-01

    Fatty acid alkyl esters, also called biodiesel, are environmentally friendly and show great potential as an alternative liquid fuel. Biodiesel is produced by transesterification of oils or fats with chemical catalysts or lipase. Immobilized lipase as the biocatalyst draws high attention because that process is "greener". This article reviews the current status of biodiesel production with immobilized lipase, including various lipases, immobilization methods, various feedstocks, lipase inactivation caused by short chain alcohols and large scale industrialization. Adsorption is still the most widely employed method for lipase immobilization. There are two kinds of lipase used most frequently especially for large scale industrialization. One is Candida antartica lipase immobilized on acrylic resin, and the other is Candida sp. 99-125 lipase immobilized on inexpensive textile membranes. However, to further reduce the cost of biodiesel production, new immobilization techniques with higher activity and stability still need to be explored. PMID:20580809

  13. Biodiesel production with immobilized lipase: A review.

    PubMed

    Tan, Tianwei; Lu, Jike; Nie, Kaili; Deng, Li; Wang, Fang

    2010-01-01

    Fatty acid alkyl esters, also called biodiesel, are environmentally friendly and show great potential as an alternative liquid fuel. Biodiesel is produced by transesterification of oils or fats with chemical catalysts or lipase. Immobilized lipase as the biocatalyst draws high attention because that process is "greener". This article reviews the current status of biodiesel production with immobilized lipase, including various lipases, immobilization methods, various feedstocks, lipase inactivation caused by short chain alcohols and large scale industrialization. Adsorption is still the most widely employed method for lipase immobilization. There are two kinds of lipase used most frequently especially for large scale industrialization. One is Candida antartica lipase immobilized on acrylic resin, and the other is Candida sp. 99-125 lipase immobilized on inexpensive textile membranes. However, to further reduce the cost of biodiesel production, new immobilization techniques with higher activity and stability still need to be explored.

  14. Polymer nanoreactors shown to produce and release antibiotics locally.

    PubMed

    Langowska, Karolina; Palivan, Cornelia G; Meier, Wolfgang

    2013-01-01

    We designed and prepared nanoreactors based on a poly(2-methyloxazoline)-block-poly(dimethylsiloxane)-block-poly(2-methyloxazoline (PMOXA-b-PDMS-b-PMOXA) amphiphilic triblock copolymer encapsulating the enzyme penicillin acylase for local and controlled production of antibiotics.

  15. Immobilization of iodine in concrete

    DOEpatents

    Clark, Walter E.; Thompson, Clarence T.

    1977-04-12

    A method for immobilizing fission product radioactive iodine recovered from irradiated nuclear fuel comprises combining material comprising water, Portland cement and about 3-20 wt. % iodine as Ba(IO.sub.3).sub.2 to provide a fluid mixture and allowing the fluid mixture to harden, said Ba(IO.sub.3).sub.2 comprising said radioactive iodine. An article for solid waste disposal comprises concrete prepared by this method. BACKGROUND OF THE INVENTION This invention was made in the course of, or under a contract with the Energy Research and Development Administration. It relates in general to reactor waste solidification and more specifically to the immobilization of fission product radioactive iodine recovered from irradiated nuclear fuel for underground storage.

  16. Plutonium Immobilization Project -- Can loading

    SciTech Connect

    Kriikku, E.

    2000-01-18

    The Savannah River Site (SRS) will immobilize excess plutonium in the proposed Plutonium Immobilization Project (PIP). The PIP scope includes unloading transportation containers, preparing the feed streams, converting the metal feed to an oxide, adding the ceramic precursors, pressing the pucks, inspecting pucks, and sintering pucks. The PIP scope also includes loading the pucks into metal cans, sealing the cans, inspecting the cans, loading the cans into magazines, loading magazines into Defense Waste Processing Facility (DWPF) canisters, and transporting the canisters to the DWPF. The DWPF fills the canister with a mixture of high level radioactive waste and glass for permanent storage. Due to the radiation, remote equipment must perform PIP operations in a contained environment.

  17. Spine Immobilizer for Accident Victims

    NASA Technical Reports Server (NTRS)

    Vykukal, H. C.; Lampson, K.

    1983-01-01

    Proposed conformal bladder filled with tiny spheres called "microballoons," enables spine of accident victim to be rapidly immobilized and restrained and permit victim to be safely removed from accident scene in extremely short time after help arrives. Microballoons expand to form rigid mass when pressure within bladder is less than ambient. Bladder strapped to victim is also strapped to rescue chair. Void between bladder and chair is filled with cloth wedges.

  18. Industrial applications of immobilized cells

    SciTech Connect

    Linko, P.; Linko, Y.Y.

    1984-01-01

    Although the application of the natural attraction of many microorganisms to surfaces has been applied in vinegar production since the early 1980s, and has long been utilized in waste water purification, the development of microbial cell immobilization techniques for special applications dates back only to the early 1960s. The immobilization may involve whole cells, cell fragments, or lysed cells. Whole cells may retain their metabolic activity with their complex multienzyme systems and cofactor regeneration mechanisms intact, or they may be killed in the process with only a few desired enzymes remaining active in the final biocatalyst. Cells may also be coimmobilized with an enzyme to carry out special reactions. Although relatively few industrial scale applications exist today, some are of very large scale. Current applications vary from relatively small scale steroid conversions to amino acid production and high fructose syrup manufacture. A vast number of potential applications are already known, and one of the most interesting applications may be in continuous fermentation such as ethanol production by immobilized living microorganisms. 373 references.

  19. Photo induced surface heparin immobilization.

    PubMed

    Nakayama, Y; Matsuda, T

    1993-01-01

    This paper describes a novel method providing durable layering of heparin immobilized hydrogels on fabricated devices. The preparation method is based on photochemistry of a dithiocarbamate group that is dissociated into a highly reactive radical pair upon ultraviolet (UV) irradiation. By taking advantage of characteristics of the photo generated radicals, hydrogel formation and its fixation onto a substrate surface were attained. The immobilization of heparin onto poly(ethylene terephtalate) was demonstrated. First, a mixed aqueous solution containing a photoreactive water soluble poly(N,N-dimethylacrylamide-covinylbenzyl N,N-diethyldithiocarbamate) and heparin was coated on the substrate. Subsequent UV irradiation resulted in the simultaneous formation of a heparin immobilized hydrogel and its chemical fixation onto the substrate. No delamination was found after vigorous washing with water. Significant inhibition of platelet adhesion and markedly prolonged blood coagulation times were observed, which are apparently derived from the surface hydrogel, and from released and chemically fixed surface heparin. Thus, it is expected that the photochemical method developed here provides potent antithrombogenicity to artificial organs. PMID:8268639

  20. IV Penicillin G is as effective as IV cefuroxime in treating community-acquired pneumonia in children.

    PubMed

    Amarilyo, Gil; Glatstein, Miguel; Alper, Arik; Scolnik, Dennis; Lavie, Moran; Schneebaum, Nira; Grisaru-Soen, Galia; Assia, Ayala; Ben-Sira, Liat; Reif, Shimon

    2014-01-01

    Overuse of broad-spectrum antimicrobials has resulted in bacterial resistance and increasing use of relatively expensive antibiotics for community-acquired pneumonia (CAP). We hypothesized that CAP requiring parenteral medication is still curable with narrow-spectrum and inexpensive penicillin G. A prospective, randomized study was performed on 58 children aged 3 months to 15 years with CAP. Children were randomly assigned to receive low-dose penicillin G, high penicillin G, or cefuroxime intravenously for 4-7 days. The course of illness was monitored clinically and with predetermined laboratory and radiological indices for 30 days. The children recovered at the same rate with no significant differences in time to defervescence or duration of hospitalization. Observed differences in leukocyte counts and C-reactive protein at discharge were of questionable clinical significance. Penicillin G is as effective and safe as cefuroxime for CAP in otherwise healthy children, even in moderate doses.

  1. A low detection limit penicillin biosensor based on single graphene nanosheets preadsorbed with hematein/ionic liquids/penicillinase.

    PubMed

    Wu, Yueting; Tang, Lele; Huang, Linhong; Han, Zhizhong; Wang, Jian; Pan, Haibo

    2014-06-01

    In this study, we reported on a low detection limit penicillin biosensor with layer-by-layer (LbL) film containing single-graphene nanosheets (SGNs) preadsorbed with hematein, ionic liquids (ILs) and penicillinase. The penicillinase catalyzes the hydrolysis of penicillin to penicilloic acid, where H(+) is liberated and monitored amperometrically with hematein as a pH indicator. The SGN-hematein/ILs/penicillinase biosensor exhibited excellent performance for penicillin in PBS with a wide range from 1.25×10(-13) to 7.5×10(-3)M, and a low detection limit of 10(-13)M (0.04ppt, S/N≥3). Furthermore, the detection of penicillin concentration in real sample (milk) had acceptable accuracy with the assay system.

  2. Purification and sequencing of the active site tryptic peptide from penicillin-binding protein 1b of Escherichia coli

    SciTech Connect

    Nicholas, R.A.; Suzuki, H.; Hirota, Y.; Strominger, J.L.

    1985-07-02

    This paper reports the sequence of the active site peptide of penicillin-binding protein 1b from Escherichia coli. Purified penicillin-binding protein 1b was labeled with (/sup 14/C)penicillin G, digested with trypsin, and partially purified by gel filtration. Upon further purification by high-pressure liquid chromatography, two radioactive peaks were observed, and the major peak, representing over 75% of the applied radioactivity, was submitted to amino acid analysis and sequencing. The sequence Ser-Ile-Gly-Ser-Leu-Ala-Lys was obtained. The active site nucleophile was identified by digesting the purified peptide with aminopeptidase M and separating the radioactive products on high-pressure liquid chromatography. Amino acid analysis confirmed that the serine residue in the middle of the sequence was covalently bonded to the (/sup 14/C)penicilloyl moiety. A comparison of this sequence to active site sequences of other penicillin-binding proteins and beta-lactamases is presented.

  3. A sensitive and selective immuno-nanogold resonance-scattering spectral method for the determination of trace penicillin G.

    PubMed

    Jiang, Zhiliang; Li, Yan; Liang, Aihui; Qin, Aimiao

    2008-01-01

    A sensitive and selective immuno-nanogold resonance scattering spectral assay was developed for the determination of trace hapten penicillin G, based on the resonance scattering (RS) effect of the nanogold at 560 nm, and the nanogold-labelled immunoreaction took place in pH 5.4 phosphate citric acid buffer solutions and in the presence of polythylene glycol (PEG). The nanogold-labelled immunocomplex formed more and more with addition of penicillin G. The enhanced RS intensity at 560 nm Delta I(RS) was linear to the penicillin G concentration in the range 7.5-1700 ng/mL, with a detection limit of 0.78 ng/mL. The results indicate that the immunonanogold-labelled RS spectral assay has a high specificity and sensitivity for quantitative determination of penicillin G in raw milk samples.

  4. Basic aspects related to penicillin-allergy skin testing: on the variability of the hapten-paratope interaction.

    PubMed

    Bondaruk, J; Curcio-Vonlanthen, V; Schneider, C H

    1995-08-01

    Ampicillin and benzylpenicillin conjugated to human serum albumin were used as immunogens in order to obtain antihaptenic IgG responses in outbred guinea pigs according to different schedules, all involving complete Freund's adjuvant. The individual responses were characterized by ELISA and by ELISA inhibition using ampicillin, benzylpenicillin, and carbenicillin peptidic conjugates for coating and for inhibition. In several instances, drastically reduced cross-reactivity and even its absence were observed, although the penicillin antigens differ only in the side-chain. The notion that the invariantly present thiazolidine ring will always provide significant binding to antibodies against all penicillins differing only in the side-chain has to be dropped. The experiments were performed in relation to newer findings of clinical penicillin-allergy skin testing which suggest that benzylpenicillin-based reagents alone are not able to detect or predict all reactions against semisynthetic penicillins. The experimental evidence here obtained corroborates this conclusion.

  5. Protein immobilization techniques for microfluidic assays

    PubMed Central

    Kim, Dohyun; Herr, Amy E.

    2013-01-01

    Microfluidic systems have shown unequivocal performance improvements over conventional bench-top assays across a range of performance metrics. For example, specific advances have been made in reagent consumption, throughput, integration of multiple assay steps, assay automation, and multiplexing capability. For heterogeneous systems, controlled immobilization of reactants is essential for reliable, sensitive detection of analytes. In most cases, protein immobilization densities are maximized, while native activity and conformation are maintained. Immobilization methods and chemistries vary significantly depending on immobilization surface, protein properties, and specific assay goals. In this review, we present trade-offs considerations for common immobilization surface materials. We overview immobilization methods and chemistries, and discuss studies exemplar of key approaches—here with a specific emphasis on immunoassays and enzymatic reactors. Recent “smart immobilization” methods including the use of light, electrochemical, thermal, and chemical stimuli to attach and detach proteins on demand with precise spatial control are highlighted. Spatially encoded protein immobilization using DNA hybridization for multiplexed assays and reversible protein immobilization surfaces for repeatable assay are introduced as immobilization methods. We also describe multifunctional surface coatings that can perform tasks that were, until recently, relegated to multiple functional coatings. We consider the microfluidics literature from 1997 to present and close with a perspective on future approaches to protein immobilization. PMID:24003344

  6. Penicillin-bound polyacrylate nanoparticles: restoring the activity of beta-lactam antibiotics against MRSA.

    PubMed

    Turos, Edward; Reddy, G Suresh Kumar; Greenhalgh, Kerriann; Ramaraju, Praveen; Abeylath, Sampath C; Jang, Seyoung; Dickey, Sonja; Lim, Daniel V

    2007-06-15

    This report describes the preparation of antibacterially active emulsified polyacrylate nanoparticles in which a penicillin antibiotic is covalently conjugated onto the polymeric framework. These nanoparticles were prepared in water by emulsion polymerization of an acrylated penicillin analogue pre-dissolved in a 7:3 (w:w) mixture of butyl acrylate and styrene in the presence of sodium dodecyl sulfate (surfactant) and potassium persulfate (radical initiator). Dynamic light scattering analysis and atomic force microscopy images show that the emulsions contain nanoparticles of approximately 40 nm in diameter. The nanoparticles have equipotent in vitro antibacterial properties against methicillin-susceptible and methicillin-resistant forms of Staphylococcus aureus and indefinite stability toward beta-lactamase. PMID:17420125

  7. Family shuffling of expandase genes to enhance substrate specificity for penicillin G.

    PubMed

    Hsu, Jyh-Shing; Yang, Yunn-Bor; Deng, Chan-Hui; Wei, Chia-Li; Liaw, Shwu-Huey; Tsai, Ying-Chieh

    2004-10-01

    Deacetoxycephalosporin C synthase (expandase) from Streptomyces clavuligerus, encoded by cefE, is an important industrial enzyme for the production of 7-aminodeacetoxycephalosporanic acid from penicillin G. To improve the substrate specificity for penicillin G, eight cefE-homologous genes were directly evolved by using the DNA shuffling technique. After the first round of shuffling and screening, using an Escherichia coli ESS bioassay, four chimeras with higher activity were subjected to a second round. Subsequently, 20 clones were found with significantly enhanced activity. The kinetic parameters of two isolates that lack substrate inhibition showed 8.5- and 118-fold increases in the k(cat)/K(m) ratio compared to the S. clavuligerus expandase. The evolved enzyme with the 118-fold increase is the most active obtained to date anywhere. Our shuffling results also indicate the remarkable plasticity of the expandase, suggesting that more-active chimeras might be achievable with further rounds. PMID:15466573

  8. Changes in penicillin-binding proteins during sporulation of Bacillus subtilis.

    PubMed Central

    Sowell, M O; Buchanan, C E

    1983-01-01

    The penicillin-binding proteins (PBPs) of Bacillus subtilis were examined in samples collected at various times from sporulating cultures and compared with the PBPs in a presporulation sample. Large increases in vegetative PBPs 2B and 3 and the appearance of at least one new PBP (42,000 daltons) occurred at reproducible times during sporulation. In some strains a second new PBP (60,000 daltons) was also produced. By comparing the PBP activities in sporulating cells and two spo0 mutants we have classified these changes as sporulation-related events rather than the consequences of stationary-phase aging. The other vegetative PBPs (PBPs 1, 2A, 4, and 5) decreased during sporulation, but not in sufficient amount or at the appropriate time to account for the appearance of the new proteins. A possible connection between specific PBP changes and the penicillin-sensitive stages of sporulation is suggested. Images PMID:6402492

  9. Acyltransferase activities of the high-molecular-mass essential penicillin-binding proteins.

    PubMed

    Adam, M; Damblon, C; Jamin, M; Zorzi, W; Dusart, V; Galleni, M; el Kharroubi, A; Piras, G; Spratt, B G; Keck, W

    1991-10-15

    The high-molecular-mass penicillin-binding proteins (HMM-PBPs), present in the cytoplasmic membranes of all eubacteria, are involved in important physiological events such as cell elongation, septation or shape determination. Up to now it has, however, been very difficult or impossible to study the catalytic properties of the HMM-PBPs in vitro. With simple substrates, we could demonstrate that several of these proteins could catalyse the hydrolysis of some thioesters or the transfer of their acyl moiety on the amino group of a suitable acceptor nucleophile. Many of the acyl-donor substrates were hippuric acid or benzoyl-D-alanine derivatives, and their spectroscopic properties enabled a direct monitoring of the enzymic reaction. In their presence, the binding of radioactive penicillin to the PBPs was also inhibited. PMID:1953655

  10. Trimethopim-sulfamethoxazole compared with benzathine penicillin for treatment of impetigo in Aboriginal children: a pilot randomised controlled trial.

    PubMed

    Tong, Steven Y C; Andrews, Ross M; Kearns, Therese; Gundjirryirr, Rosalyn; McDonald, Malcolm I; Currie, Bart J; Carapetis, Jonathan R

    2010-03-01

    We conducted a pilot randomized controlled trial comparing trimethoprim-sulfamethoxazole to benzathine penicillin for treatment of impetigo in Aboriginal children. Treatment was successful in 7 of 7 children treated with trimethoprim-sulfamethoxazole and 5 of 6 treated with benzathine penicillin. Trimethoprim-sulfamethoxazole achieved microbiological clearance and healing of sores from which beta-hemolytic streptococci and community-associated methicillin-resistant Staphylococcus aureus were initially cultured.

  11. Penicillin-induced epilepsy model in rats: dose-dependant effect on hippocampal volume and neuron number.

    PubMed

    Akdogan, Ilgaz; Adiguzel, Esat; Yilmaz, Ismail; Ozdemir, M Bulent; Sahiner, Melike; Tufan, A Cevik

    2008-10-22

    This study was designed to evaluate the penicillin-induced epilepsy model in terms of dose-response relationship of penicillin used to induce epilepsy seizure on hippocampal neuron number and hippocampal volume in Sprague-Dawley rats. Seizures were induced with 300, 500, 1500 and 2000IU of penicillin-G injected intracortically in rats divided in four experimental groups, respectively. Control group was injected intracortically with saline. Animals were decapitated on day 7 of treatment and brains were removed. The total neuron number of pyramidal cell layer from rat hippocampus was estimated using the optical fractionator method. The volume of same hippocampal areas was estimated using the Cavalieri method. Dose-dependent decrease in hippocampal neuron number was observed in three experimental groups (300, 500 and 1500IU of penicillin-G), and the effects were statistically significant when compared to the control group (P<0.009). Dose-dependent decrease in hippocampal volume, on the other hand, was observed in all three of these groups; however, the difference compared to the control group was only statistically significant in 1500IU of penicillin-G injected group (P<0.009). At the dose of 2000IU penicillin-G, all animals died due to status seizures. These results suggest that the appropriate dose of penicillin has to be selected for a given experimental epilepsy study in order to demonstrate the relevant epileptic seizure and its effects. Intracortical 1500IU penicillin-induced epilepsy model may be a good choice to practice studies that investigate neuroprotective mechanisms of the anti-epileptic drugs.

  12. Effect of penicillin on the adherence of Streptococcus sanguis in vitro and in the rabbit model of endocarditis.

    PubMed

    Lowy, F D; Chang, D S; Neuhaus, E G; Horne, D S; Tomasz, A; Steigbigel, N H

    1983-03-01

    The effect of penicillin treatment of Streptococcus sanguis in vitro, on subsequent bacterial density in the bloodstream and on cardiac valves in the rabbit model of endocarditis was studied. As experimental tools for this study, isogenic pairs of S. sanguis differing in resistance to streptomycin or rifampin were prepared by genetic transformation. Rabbits with traumatized heart valves received an intravenous inoculation of penicillin treated (1 mug/ml) and untreated S. sanguis, each marked by resistance to either streptomycin or rifampin. The number of penicillin-treated and untreated bacteria attached to the valvular surfaces was determined by differential counting on streptomycin or rifampin containing media. Penicillin pretreatment reduced cardiac valve colonization 5 min after inoculation ("adherence ratio" x 10(8) was 4.11 for the control and 3.66 for the penicillin-treated bacteria, P < 0.001). The results were not due to differences in serum killing or bacterial densities in the bloodstream. There was no difference in valvular bacterial densities 24 h after bacterial inoculation (adherence ratio x 10(8), 7.26 untreated vs. 6.34 penicillin-pretreated, P > 0.10). In vitro experiments were performed using platelet-fibrin surfaces to test the possibility that penicillin-induced loss of lipoteichoic acid was responsible for decreased streptococcal adherence. Pretreatment of S. sanguis cultures with inhibitory concentrations of penicillin or with antiserum against lipoteichoic acid and precoating of the platelet-fibrin surfaces with lipoteichoic acid, all caused reduction in bacterial adherence. The findings are interpreted as support for the role of lipoteichoic acid as an adhesin in S. sanguis interactions with particular host tissue surfaces.

  13. Effect of Electrolyte on the Surface and Thermodynamic Properties of Amphiphilic Penicillins.

    PubMed

    Taboada; Attwood; Ruso; García; Sarmiento; Mosquera

    1999-12-15

    Critical micelle concentrations and surface properties of the penicillins cloxacillin, dicloxacillin, and nafcillin in aqueous solution at 303 K and at electrolyte concentrations over the range 0.0-0.4 mol dm(-3) were determined by surface tension measurements. A mass action model, modified for application to associating systems of low aggregation number, was used to calculate the standard Gibbs energy of micellization of these drugs at each electrolyte concentration. Copyright 1999 Academic Press.

  14. Transmissible Resistance to Penicillin G, Neomycin, and Chloramphenicol in Rhizobium japonicum1

    PubMed Central

    Cole, Michael A.; Elkan, Gerald H.

    1973-01-01

    The genetic basis for resistance to a number of antibiotics was examined in Rhizobium japonicum. Resistance to penicillin G, neomycin, and chloramphenicol appears to be mediated by an extrachromosomal element similar to that found in the Enterobacteriaceae. Resistance to these antibiotics was eliminated from cells by treatment with acridine orange, and resistance to all three antibiotics could be transferred en bloc to Agrobacterium tumefaciens under conditions excluding transformation or transduction as possible genetic mechanisms. PMID:4491197

  15. Production, Extraction, and Qualitative Testing of Penicillin: A Biochemistry Experiment for Health Science Chemistry Courses

    NASA Astrophysics Data System (ADS)

    Stevens, Richard E.; Billingsley, Kara C.

    1998-10-01

    This laboratory procedure guides students through the growth of a submerged Penicillium chrysogenum culture. Subsequent steps include extraction of the penicillin by adsorption onto activated charcoal, extraction with acetone, and qualitative testing of the drug on a bacterial culture. The laboratory procedure is designed for freshman-level health science chemistry courses. This procedure produces minimal waste, which can be disposed of by the appropriate use of an autoclave.

  16. Molecular epidemiology of penicillin-non-susceptible Streptococcus pneumoniae isolates from children with invasive pneumococcal disease in Germany.

    PubMed

    Reinert, R R; van der Linden, M; Seegmüller, I; Al-Lahham, A; Siedler, A; Weissmann, B; Toschke, A M; von Kries, R

    2007-04-01

    A population-based nationwide surveillance of antibiotic resistance associated with invasive pneumococcal disease (IPD) in children and adolescents (aged<16 years) was performed in Germany between 1997 and 2004. In total, 1517 isolates were collected, of which 5.1% and 1.1% were intermediately- or fully-resistant, respectively, to penicillin G. During the 8-year study period, an increase in resistance to both penicillin G and erythromycin A was observed, and the frequency of isolates exhibiting reduced susceptibility to penicillin G or erythromycin A increased from 1.4% and 11.1%, respectively, in 1997, to 8.7% and 29.0%, respectively, in 2004. Among the penicillin non-susceptible pneumococcal isolates, serotypes 14 (24.5% of isolates), 23F (16.0%) and 6B (16.0%) were found most frequently. Multilocus sequence typing of 58 (62%) penicillin G non-susceptible isolates revealed that sequence type (ST) 156 (Spain9V-3 clone) and its single-locus variant ST 557 were widespread in Germany. Moreover, 17 new penicillin G non-susceptible STs were defined for the first time. The study illustrated the genetic heterogeneity of antibiotic-resistant pneumococcal isolates in Germany. PMID:17359319

  17. Ligand Replacement Approach to Raman-Responded Molecularly Imprinted Monolayer for Rapid Determination of Penicilloic Acid in Penicillin.

    PubMed

    Zhang, Liying; Jin, Yang; Huang, Xiaoyan; Zhou, Yujie; Du, Shuhu; Zhang, Zhongping

    2015-12-01

    Penicilloic acid (PA) is a degraded byproduct of penicillin and often causes fatal allergies to humans, but its rapid detection in penicillin drugs remains a challenge due to its similarity to the mother structure of penicillin. Here, we reported a ligand-replaced molecularly imprinted monolayer strategy on a surface-enhanced Raman scattering (SERS) substrate for the specific recognition and rapid detection of Raman-inactive PA in penicillin. The bis(phenylenediamine)-Cu(2+)-PA complex was first synthesized and stabilized onto the surface of silver nanoparticle film that was fabricated by a bromide ion-added silver mirror reaction. A molecularly imprinted monolayer was formed by the further modification of alkanethiol around the stabilized complex on the Ag film substrate, and the imprinted recognition site was then created by the replacement of the complex template with Raman-active probe molecule p-aminothiophenol. When PA rebound into the imprinted site in the alkanethiol monolayer, the SERS signal of p-aminothiophenol exhibited remarkable enhancement with a detection limit of 0.10 nM. The imprinted monolayer can efficiently exclude the interference of penicillin and thus provides a selective determination of 0.10‰ (w/w) PA in penicillin, which is about 1 order of magnitude lower than the prescribed residual amount of 1.0‰. The strategy reported here is simple, rapid and inexpensive compared to the traditional chromatography-based methods. PMID:26545037

  18. Production of anti-amoxicillin ScFv antibody and simulation studying its molecular recognition mechanism for penicillins.

    PubMed

    Liu, Jing; Zhang, Hui C; Duan, Chang F; Dong, Jun; Zhao, Guo X; Wang, Jian P; Li, Nan; Liu, Jin Z; Li, Yu W

    2016-11-01

    The molecular recognition mechanism of an antibody for its hapten is very interesting. The objective of this research was to study the intermolecular interactions of an anti-amoxicillin antibody with penicillin drugs. The single chain variable fragment (ScFv) antibody was generated from a hybridoma cell strain excreting the monoclonal antibody for amoxicillin. The recombinant ScFv antibody showed similar recognition ability for penicillins to its parental monoclonal antibody: simultaneous recognizing 11 penicillins with cross-reactivities of 18-107%. The three-dimensional structure of the ScFv antibody was simulated by using homology modeling, and its intermolecular interactions with 11 penicillins were studied by using molecular docking. Results showed that three CDRs are involved in antibody recognition; CDR L3 Arg 100, CDR H3 Tyr226, and CDR H3 Arg 228 were the key contact amino acid residues; hydrogen bonding was the main antibody-drug intermolecular force; and the core structure of penicillin drugs was the main antibody binding position. These results could explain the recognition mechanism of anti-amoxicillin antibody for amoxicillin and its analogs. This is the first study reporting the production of ScFv antibody for penicillins and stimulation studying its recognition mechanism.

  19. Ligand Replacement Approach to Raman-Responded Molecularly Imprinted Monolayer for Rapid Determination of Penicilloic Acid in Penicillin.

    PubMed

    Zhang, Liying; Jin, Yang; Huang, Xiaoyan; Zhou, Yujie; Du, Shuhu; Zhang, Zhongping

    2015-12-01

    Penicilloic acid (PA) is a degraded byproduct of penicillin and often causes fatal allergies to humans, but its rapid detection in penicillin drugs remains a challenge due to its similarity to the mother structure of penicillin. Here, we reported a ligand-replaced molecularly imprinted monolayer strategy on a surface-enhanced Raman scattering (SERS) substrate for the specific recognition and rapid detection of Raman-inactive PA in penicillin. The bis(phenylenediamine)-Cu(2+)-PA complex was first synthesized and stabilized onto the surface of silver nanoparticle film that was fabricated by a bromide ion-added silver mirror reaction. A molecularly imprinted monolayer was formed by the further modification of alkanethiol around the stabilized complex on the Ag film substrate, and the imprinted recognition site was then created by the replacement of the complex template with Raman-active probe molecule p-aminothiophenol. When PA rebound into the imprinted site in the alkanethiol monolayer, the SERS signal of p-aminothiophenol exhibited remarkable enhancement with a detection limit of 0.10 nM. The imprinted monolayer can efficiently exclude the interference of penicillin and thus provides a selective determination of 0.10‰ (w/w) PA in penicillin, which is about 1 order of magnitude lower than the prescribed residual amount of 1.0‰. The strategy reported here is simple, rapid and inexpensive compared to the traditional chromatography-based methods.

  20. Human Chlamydia pneumoniae isolates demonstrate ability to recover infectivity following penicillin treatment whereas animal isolates do not.

    PubMed

    Chacko, Anu; Beagley, Kenneth W; Timms, Peter; Huston, Wilhelmina M

    2015-03-01

    Chlamydia pneumoniae strains have recently been demonstrated to have substantially different capacities to enter and recover from IFN-γ-induced persistence, depending on whether they are from human or animal host sources. Here, we examined the ability of two human and two animal strains to enter and be rescued from penicillin-induced persistence. The ability to form inclusions after the addition of penicillin was much reduced in the two animal isolates (koala LPCoLN, bandicoot B21) compared to the two human isolates (respiratory AR39 and heart A03). The penicillin treatment resulted in a dose-dependent loss of infectious progeny for all isolates, with the human strains failing to produce infectious progeny at lower doses of penicillin than the animal strains. The most remarkable finding however was the contrasting ability of the isolates to recover infectious progeny production after rescue by removal of the penicillin (at 72 h) and continued culture. The animal isolates both showed virtually no recovery from the penicillin treatment conditions. In contrast, the human isolates showed a significant ability to recovery infectivity, with the heart isolate (A03) showing the most marked recovery. Combined, these data further support the hypothesis that the ability to establish and recover from persistence appears to be enhanced in human C. pneumoniae strains compared to animal strains.

  1. Human Chlamydia pneumoniae isolates demonstrate ability to recover infectivity following penicillin treatment whereas animal isolates do not.

    PubMed

    Chacko, Anu; Beagley, Kenneth W; Timms, Peter; Huston, Wilhelmina M

    2015-03-01

    Chlamydia pneumoniae strains have recently been demonstrated to have substantially different capacities to enter and recover from IFN-γ-induced persistence, depending on whether they are from human or animal host sources. Here, we examined the ability of two human and two animal strains to enter and be rescued from penicillin-induced persistence. The ability to form inclusions after the addition of penicillin was much reduced in the two animal isolates (koala LPCoLN, bandicoot B21) compared to the two human isolates (respiratory AR39 and heart A03). The penicillin treatment resulted in a dose-dependent loss of infectious progeny for all isolates, with the human strains failing to produce infectious progeny at lower doses of penicillin than the animal strains. The most remarkable finding however was the contrasting ability of the isolates to recover infectious progeny production after rescue by removal of the penicillin (at 72 h) and continued culture. The animal isolates both showed virtually no recovery from the penicillin treatment conditions. In contrast, the human isolates showed a significant ability to recovery infectivity, with the heart isolate (A03) showing the most marked recovery. Combined, these data further support the hypothesis that the ability to establish and recover from persistence appears to be enhanced in human C. pneumoniae strains compared to animal strains. PMID:25663156

  2. Determination of penicillin G in milk samples using its effect on cloud point extraction of triiodide ion.

    PubMed

    Pourreza, Nahid; Fat'hi, Mohammad Reza; Hatami, Ali

    2014-01-01

    A cloud point extraction (CPE) method for determination of trace amounts of penicillin G by spectrophotometry based on its effect on the triiodide ion (I3(-)) has been developed. Penicillin G is converted to the corresponding penicilloic acid by carrying out hydrolysis with sodium hydroxide solution, and treatment with acid yields D-penicillamine that is oxidized quantitatively by iodine to give rise to a disulfide. The 13- remaining in the solution is extracted into the surfactant Triton X-100, and the difference between absorbance of the working solution in the presence and absence of penicillin G is proportional to the amount of penicillin G. The effects of different variables, such as concentrations of sodium hydroxide, hydrochloric acid, surfactant, and I3(-) and the temperature and incubation time on the CPE were studied. The calibration graph was linear in the range of 50-1250 microg/L, and the LOD was 38 microg/L (n = 10). The RSD for 10 replicate determinations of 1000 microg/L of penicillin G was 1.0%. The method was applied to the determination of penicillin G in milk samples.

  3. Ceftibuten-containing agar plate for detecting group B streptococci with reduced penicillin susceptibility (PRGBS).

    PubMed

    Kamiya, Chitose; Kimura, Kouji; Doyama, Yo; Miyazaki, Akira; Morimoto, Makiko; Banno, Hirotsugu; Nagano, Noriyuki; Jin, Wanchun; Wachino, Jun-ichi; Yamada, Keiko; Arakawa, Yoshichika

    2015-08-01

    Penicillins remain first-line agents for treatment of group B Streptococcus (Streptococcus agalactiae; GBS) infections; however, several reports have confirmed the existence of GBS with reduced penicillin susceptibility (PRGBS). Because no selective agar plates for detection of PRGBS are available to date, in this investigation, we developed the selective agar plate for detection of PRGBS. We used 19 genetically well-confirmed PRGBS isolates and 38 penicillin-susceptible GBS isolates identified in Japan. For preparation of trial PRGBS-selective agar plates, we added 1 of antimicrobial agents (among oxacillin, ceftizoxime, and ceftibuten) to a well-established GBS-selective agar plate. Among 12 trial PRGBS-selective agar plates, Muller-Hinton agar containing 128 μg/mL ceftibuten with 5% sheep blood, 8 μg/mL gentamicin, and 12 μg/mL nalidixic acid was the most appropriate selective agar for PRGBS, showing 100% sensitivity and 81.6% specificity. In cases of potential nosocomial spread of PRGBS, the selective agar plate could be useful and reliable.

  4. Proteochemometric model for predicting the inhibition of penicillin-binding proteins.

    PubMed

    Nabu, Sunanta; Nantasenamat, Chanin; Owasirikul, Wiwat; Lawung, Ratana; Isarankura-Na-Ayudhya, Chartchalerm; Lapins, Maris; Wikberg, Jarl E S; Prachayasittikul, Virapong

    2015-02-01

    Neisseria gonorrhoeae infection threatens to become an untreatable sexually transmitted disease in the near future owing to the increasing emergence of N. gonorrhoeae strains with reduced susceptibility and resistance to the extended-spectrum cephalosporins (ESCs), i.e. ceftriaxone and cefixime, which are the last remaining option for first-line treatment of gonorrhea. Alteration of the penA gene, encoding penicillin-binding protein 2 (PBP2), is the main mechanism conferring penicillin resistance including reduced susceptibility and resistance to ESCs. To predict and investigate putative amino acid mutations causing β-lactam resistance particularly for ESCs, we applied proteochemometric modeling to generalize N. gonorrhoeae susceptibility data for predicting the interaction of PBP2 with therapeutic β-lactam antibiotics. This was afforded by correlating publicly available data on antimicrobial susceptibility of wild-type and mutant N. gonorrhoeae strains for penicillin-G, cefixime and ceftriaxone with 50 PBP2 protein sequence data using partial least-squares projections to latent structures. The generated model revealed excellent predictability (R2=0.91, Q2=0.77, QExt2=0.78). Moreover, our model identified amino acid mutations in PBP2 with the highest impact on antimicrobial susceptibility and provided information on physicochemical properties of amino acid mutations affecting antimicrobial susceptibility. Our model thus provided insight into the physicochemical basis for resistance development in PBP2 suggesting its use for predicting and monitoring novel PBP2 mutations that may emerge in the future.

  5. Effect of penicillin on fatty acid synthesis and excretion in Streptococcus mutans BHT

    SciTech Connect

    Brissette, J.L.; Pieringer, R.A.

    1985-03-01

    Treatment of exponentially growing cultures of Streptococcus mutans BHT with growth-inhibitory concentrations (0.2 microgram/ml) of benzylpenicillin stimulates the incorporation of (2-/sup 14/C) acetate into lipids excreted by the cells by as much as 69-fold, but does not change the amount of /sup 14/C incorporated into intracellular lipids. At this concentration of penicillin cellular lysis does not occur. The radioactive label is incorporated exclusively into the fatty acid moieties of the glycerolipids. During a 4-hr incubation in the presence of penicillin, the extracellular fatty acid ester concentration increases 1.5 fold, even though there is no growth or cellular lysis. An indication of the relative rate of fatty acid synthesis was most readily obtained by placing S. mutans BHT in a buffer containing /sup 14/C-acetate. Under these nongrowing conditions free fatty acids are the only lipids labeled, a factor which simplifies the assay. The addition of glycerol to the buffer causes all of the nonesterified fatty acids to be incorporated into glycerolipid. The cells excrete much of the lipid whether glycerol is present or not. Addition of penicillin to the nongrowth supporting buffer system does not stimulate the incorporation of (/sup 14/C)-acetate into fatty acids.

  6. Long-term use of penicillin for the treatment of chronic plaque psoriasis.

    PubMed

    Saxena, V N; Dogra, J

    2005-01-01

    A continuing sub-clinical streptococcal infection might be responsible for chronic plaque psoriasis. In this open study, we investigated thirty patients with moderate to severe chronic plaque psoriasis. The majority of the patients had been ill for 5 years or more (21 out of the total 30), and they had taken various treatment modalities for psoriasis with no significant improvement and frequent relapses. Total duration of the study was two years. Initially benzathine penicillin 1.2 million units, was given I.M. AST fortnightly. After 24 weeks benzathine penicillin was reduced to 1.2 million units once a month. Relevant investigations and clinical assessment was done at regular intervals to detect side effects and to observe the progress of disease. Significant improvement in the PASI score was noted from 12 weeks onwards. All patients showed excellent improvement at 2 years. Patients tolerated the therapy well. Controlled studies are needed to further confirm the benefits of long-term use of benzathine penicillin in the treatment of psoriasis.

  7. No Resistance to Penicillin, Cefuroxime, Cefotaxime, or Vancomycin in Pneumococcal Pneumonia

    PubMed Central

    Yayan, Josef; Ghebremedhin, Beniam; Rasche, Kurt

    2015-01-01

    Objectives: Group B Streptococcus is a primary source of pneumonia, which is a leading cause of death worldwide. During the last few decades, there has been news of growing antibiotic resistance in group B streptococci to penicillin and different antibiotic agents. This clinical study retrospectively analyzes antimicrobial resistance in inpatients who were diagnosed with group B streptococcal pneumonia. Methods: All of the required information from inpatients who were identified to have group B streptococcal pneumonia was sourced from the database at the Department of Internal Medicine of HELIOS Clinic Wuppertal, Witten/Herdecke University, in Germany, from 2004-2014. Antimicrobial susceptibility testing was performed for the different antimicrobial agents that were regularly administered to these inpatients. Results: Sixty-six inpatients with a mean age of 63.3 ± 16.1 years (45 males [68.2%, 95% CI 60.0%-79.4%] and 21 females [31.8%, 95% CI 20.6%-43.0%]) were detected to have group B streptococcal pneumonia within the study period from January 1, 2004, to August 12, 2014. Group B Streptococcus had a high resistance rate to gentamicin (12.1%), erythromycin (12.1%), clindamycin (9.1%), and co-trimoxazole (3.0%), but it was not resistant to penicillin, cefuroxime, cefotaxime, or vancomycin (P < 0.0001). Conclusion: No resistance to penicillin, cefuroxime, cefotaxime, or vancomycin was detected among inpatients with pneumonia caused by group B streptococci. PMID:26664260

  8. Proteochemometric model for predicting the inhibition of penicillin-binding proteins.

    PubMed

    Nabu, Sunanta; Nantasenamat, Chanin; Owasirikul, Wiwat; Lawung, Ratana; Isarankura-Na-Ayudhya, Chartchalerm; Lapins, Maris; Wikberg, Jarl E S; Prachayasittikul, Virapong

    2015-02-01

    Neisseria gonorrhoeae infection threatens to become an untreatable sexually transmitted disease in the near future owing to the increasing emergence of N. gonorrhoeae strains with reduced susceptibility and resistance to the extended-spectrum cephalosporins (ESCs), i.e. ceftriaxone and cefixime, which are the last remaining option for first-line treatment of gonorrhea. Alteration of the penA gene, encoding penicillin-binding protein 2 (PBP2), is the main mechanism conferring penicillin resistance including reduced susceptibility and resistance to ESCs. To predict and investigate putative amino acid mutations causing β-lactam resistance particularly for ESCs, we applied proteochemometric modeling to generalize N. gonorrhoeae susceptibility data for predicting the interaction of PBP2 with therapeutic β-lactam antibiotics. This was afforded by correlating publicly available data on antimicrobial susceptibility of wild-type and mutant N. gonorrhoeae strains for penicillin-G, cefixime and ceftriaxone with 50 PBP2 protein sequence data using partial least-squares projections to latent structures. The generated model revealed excellent predictability (R2=0.91, Q2=0.77, QExt2=0.78). Moreover, our model identified amino acid mutations in PBP2 with the highest impact on antimicrobial susceptibility and provided information on physicochemical properties of amino acid mutations affecting antimicrobial susceptibility. Our model thus provided insight into the physicochemical basis for resistance development in PBP2 suggesting its use for predicting and monitoring novel PBP2 mutations that may emerge in the future. PMID:25344841

  9. Application of pbp1A PCR in Identification of Penicillin-Resistant Streptococcus pneumoniae

    PubMed Central

    du Plessis, Mignon; Smith, Anthony M.; Klugman, Keith P.

    1999-01-01

    A seminested PCR assay, based on the amplification of the pneumococcal pbp1A gene, was developed for the detection of penicillin resistance in clinical isolates of Streptococcus pneumoniae. The assay was able to differentiate between intermediate (MICs = 0.25 to 0.5 μg/ml) and higher-level (MICs = ≥1 μg/ml) resistance. Two species-specific primers, 1A-1 and 1A-2, which amplified a 1,043-bp region of the pbp1A penicillin-binding region, were used for pneumococcal detection. Two resistance primers, 1A-R1 and 1A-R2, were designed to bind to altered areas of the pbp1A gene which, together with the downstream primer 1A-2, amplify DNA from isolates with penicillin MICs of ≥0.25 and ≥1 μg/ml, respectively. A total of 183 clinical isolates were tested with the pbp1A assay. For 98.3% (180 of 183) of these isolates, the PCR results obtained were in agreement with the MIC data. The positive and negative predictive values of the assay were 100 and 91%, respectively, for detecting strains for which the MICs were ≥0.25 μg/ml and were both 100% for strains for which the MICs were ≥1 μg/ml. PMID:9986824

  10. Penicillin resistance compromises Nod1-dependent proinflammatory activity and virulence fitness of neisseria meningitidis.

    PubMed

    Zarantonelli, Maria Leticia; Skoczynska, Anna; Antignac, Aude; El Ghachi, Meriem; Deghmane, Ala-Eddine; Szatanik, Marek; Mulet, Céline; Werts, Catherine; Peduto, Lucie; d'Andon, Martine Fanton; Thouron, Françoise; Nato, Faridabano; Lebourhis, Lionel; Philpott, Dana J; Girardin, Stephen E; Vives, Francina Langa; Sansonetti, Philippe; Eberl, Gérard; Pedron, Thierry; Taha, Muhamed-Kheir; Boneca, Ivo G

    2013-06-12

    Neisseria meningitidis is a life-threatening human bacterial pathogen responsible for pneumonia, sepsis, and meningitis. Meningococcal strains with reduced susceptibility to penicillin G (Pen(I)) carry a mutated penicillin-binding protein (PBP2) resulting in a modified peptidoglycan structure. Despite their antibiotic resistance, Pen(I) strains have failed to expand clonally. We analyzed the biological consequences of PBP2 alteration among clinical meningococcal strains and found that peptidoglycan modifications of the Pen(I) strain resulted in diminished in vitro Nod1-dependent proinflammatory activity. In an influenza virus-meningococcal sequential mouse model mimicking human disease, wild-type meningococci induced a Nod1-dependent inflammatory response, colonizing the lungs and surviving in the blood. In contrast, isogenic Pen(I) strains were attenuated for such response and were out-competed by meningococci sensitive to penicillin G. Our results suggest that antibiotic resistance imposes a cost to the success of the pathogen and may potentially explain the lack of clonal expansion of Pen(I) strains. PMID:23768497

  11. Cloning and Characterization of an Aspergillus nidulans Gene Involved in the Regulation of Penicillin Biosynthesis

    PubMed Central

    Van den Brulle, Jan; Steidl, Stefan; Brakhage, Axel A.

    1999-01-01

    To identify regulators of penicillin biosynthesis, a previously isolated mutant of Aspergillus nidulans (Prg-1) which carried the trans-acting prgA1 mutation was used. This mutant also contained fusions of the penicillin biosynthesis genes acvA and ipnA with reporter genes (acvA-uidA and ipnA-lacZ) integrated in a double-copy arrangement at the chromosomal argB gene. The prgA1 mutant strain exhibited only 20 to 50% of the ipnA-lacZ and acvA-uidA expression exhibited by the wild-type strain and had only 20 to 30% of the penicillin produced by the wild-type strain. Here, using complementation with a genomic cosmid library, we isolated a gene (suAprgA1) which complemented the prgA1 phenotype to the wild-type phenotype; i.e., the levels of expression of both gene fusions and penicillin production were nearly wild-type levels. Analysis of the suAprgA1 gene in the prgA1 mutant did not reveal any mutation in the suAprgA1 gene or unusual transcription of the gene. This suggested that the suAprgA1 gene is a suppressor of the prgA1 mutation. The suAprgA1 gene is 1,245 bp long. Its five exons encode a deduced protein that is 303 amino acids long. The putative SUAPRGA1 protein was similar to both the human p32 protein and Mam33p of Saccharomyces cerevisiae. Analysis of the ordered gene library of A. nidulans indicated that suAprgA1 is located on chromosome VI. Deletion of the suAprgA1 gene resulted in an approximately 50% reduction in ipnA-lacZ expression and in a slight reduction in acvA-uidA expression. The ΔsuAprgA1 strain produced about 60% of the amount of penicillin produced by the wild-type strain. PMID:10583968

  12. Immobilization of enzymes: a literature survey.

    PubMed

    Brena, Beatriz; González-Pombo, Paula; Batista-Viera, Francisco

    2013-01-01

    The term immobilized enzymes refers to "enzymes physically confined or localized in a certain defined region of space with retention of their catalytic activities, and which can be used repeatedly and continuously." Immobilized enzymes are currently the subject of considerable interest because of their advantages over soluble enzymes. In addition to their use in industrial processes, the immobilization techniques are the basis for making a number of biotechnology products with application in diagnostics, bioaffinity chromatography, and biosensors. At the beginning, only immobilized single enzymes were used, after 1970s more complex systems including two-enzyme reactions with cofactor regeneration and living cells were developed. The enzymes can be attached to the support by interactions ranging from reversible physical adsorption and ionic linkages to stable covalent bonds. Although the choice of the most appropriate immobilization technique depends on the nature of the enzyme and the carrier, in the last years the immobilization technology has increasingly become a matter of rational design. As a consequence of enzyme immobilization, some properties such as catalytic activity or thermal stability become altered. These effects have been demonstrated and exploited. The concept of stabilization has been an important driving force for immobilizing enzymes. Moreover, true stabilization at the molecular level has been demonstrated, e.g., proteins immobilized through multipoint covalent binding. PMID:23934795

  13. Multimodular Penicillin-Binding Proteins: An Enigmatic Family of Orthologs and Paralogs

    PubMed Central

    Goffin, Colette; Ghuysen, Jean-Marie

    1998-01-01

    The monofunctional penicillin-binding dd-peptidases and penicillin-hydrolyzing serine β-lactamases diverged from a common ancestor by the acquisition of structural changes in the polypeptide chain while retaining the same folding, three-motif amino acid sequence signature, serine-assisted catalytic mechanism, and active-site topology. Fusion events gave rise to multimodular penicillin-binding proteins (PBPs). The acyl serine transferase penicillin-binding (PB) module possesses the three active-site defining motifs of the superfamily; it is linked to the carboxy end of a non-penicillin-binding (n-PB) module through a conserved fusion site; the two modules form a single polypeptide chain which folds on the exterior of the plasma membrane and is anchored by a transmembrane spanner; and the full-size PBPs cluster into two classes, A and B. In the class A PBPs, the n-PB modules are a continuum of diverging sequences; they possess a five-motif amino acid sequence signature, and conserved dicarboxylic amino acid residues are probably elements of the glycosyl transferase catalytic center. The PB modules fall into five subclasses: A1 and A2 in gram-negative bacteria and A3, A4, and A5 in gram-positive bacteria. The full-size class A PBPs combine the required enzymatic activities for peptidoglycan assembly from lipid-transported disaccharide-peptide units and almost certainly prescribe different, PB-module specific traits in peptidoglycan cross-linking. In the class B PBPs, the PB and n-PB modules cluster in a concerted manner. A PB module of subclass B2 or B3 is linked to an n-PB module of subclass B2 or B3 in gram-negative bacteria, and a PB module of subclass B1, B4, or B5 is linked to an n-PB module of subclass B1, B4, or B5 in gram-positive bacteria. Class B PBPs are involved in cell morphogenesis. The three motifs borne by the n-PB modules are probably sites for module-module interaction and the polypeptide stretches which extend between motifs 1 and 2 are sites for

  14. Immobilized lipid-bilayer materials

    DOEpatents

    Sasaki, Darryl Y.; Loy, Douglas A.; Yamanaka, Stacey A.

    2000-01-01

    A method for preparing encapsulated lipid-bilayer materials in a silica matrix comprising preparing a silica sol, mixing a lipid-bilayer material in the silica sol and allowing the mixture to gel to form the encapsulated lipid-bilayer material. The mild processing conditions allow quantitative entrapment of pre-formed lipid-bilayer materials without modification to the material's spectral characteristics. The method allows for the immobilization of lipid membranes to surfaces. The encapsulated lipid-bilayer materials perform as sensitive optical sensors for the detection of analytes such as heavy metal ions and can be used as drug delivery systems and as separation devices.

  15. Immobilization of bovine catalase onto magnetic nanoparticles.

    PubMed

    Doğaç, Yasemin İspirli; Teke, Mustafa

    2013-01-01

    The scope of this study is to achieve carrier-bound immobilization of catalase onto magnetic particles (Fe₃O₄ and Fe₂O₃NiO₂ · H₂O) to specify the optimum conditions of immobilization. Removal of H2O2 and the properties of immobilized sets were also investigated. To that end, adsorption and then cross-linking methods onto magnetic particles were performed. The optimum immobilization conditions were found for catalase: immobilization time (15 min for Fe₃O₄; 10 min for Fe2O₃NiO₂ · H₂O), the initial enzyme concentration (1 mg/mL), amount of magnetic particles (25 mg), and glutaraldehyde concentration (3%). The activity reaction conditions (optimum temperature, optimum pH, pH stability, thermal stability, operational stability, and reusability) were characterized. Also kinetic parameters were calculated by Lineweaver-Burk plots. The optimum pH values were found to be 7.0, 7.0, and 8.0 for free enzyme, Fe₃O₄-immobilized catalases, and Fe₂O₃NiO₂ · H₂O-immobilized catalases, respectively. All immobilized catalase systems displayed the optimum temperature between 25 and 35°C. Reusability studies showed that Fe₃O₄-immobilized catalase can be used 11 times with 50% loss in original activity, while Fe2O₃NiO₂ · H₂O-immobilized catalase lost 67% of activity after the same number of uses. Furthermore, immobilized catalase systems exhibited improved thermal and pH stability. The results transparently indicate that it is possible to have binding between enzyme and magnetic nanoparticles.

  16. Technetium Immobilization Forms Literature Survey

    SciTech Connect

    Westsik, Joseph H.; Cantrell, Kirk J.; Serne, R. Jeffrey; Qafoku, Nikolla

    2014-05-01

    Of the many radionuclides and contaminants in the tank wastes stored at the Hanford site, technetium-99 (99Tc) is one of the most challenging to effectively immobilize in a waste form for ultimate disposal. Within the Hanford Tank Waste Treatment and Immobilization Plant (WTP), the Tc will partition between both the high-level waste (HLW) and low-activity waste (LAW) fractions of the tank waste. The HLW fraction will be converted to a glass waste form in the HLW vitrification facility and the LAW fraction will be converted to another glass waste form in the LAW vitrification facility. In both vitrification facilities, the Tc is incorporated into the glass waste form but a significant fraction of the Tc volatilizes at the high glass-melting temperatures and is captured in the off-gas treatment systems at both facilities. The aqueous off-gas condensate solution containing the volatilized Tc is recycled and is added to the LAW glass melter feed. This recycle process is effective in increasing the loading of Tc in the LAW glass but it also disproportionally increases the sulfur and halides in the LAW melter feed which increases both the amount of LAW glass and either the duration of the LAW vitrification mission or the required supplemental LAW treatment capacity.

  17. Uranium immobilization and nuclear waste

    SciTech Connect

    Duffy, C.J.; Ogard, A.E.

    1982-02-01

    Considerable information useful in nuclear waste storage can be gained by studying the conditions of uranium ore deposit formation. Further information can be gained by comparing the chemistry of uranium to nuclear fission products and other radionuclides of concern to nuclear waste disposal. Redox state appears to be the most important variable in controlling uranium solubility, especially at near neutral pH, which is characteristic of most ground water. This is probably also true of neptunium, plutonium, and technetium. Further, redox conditions that immobilize uranium should immobilize these elements. The mechanisms that have produced uranium ore bodies in the Earth's crust are somewhat less clear. At the temperatures of hydrothermal uranium deposits, equilibrium models are probably adequate, aqueous uranium (VI) being reduced and precipitated by interaction with ferrous-iron-bearing oxides and silicates. In lower temperature roll-type uranium deposits, overall equilibrium may not have been achieved. The involvement of sulfate-reducing bacteria in ore-body formation has been postulated, but is uncertain. Reduced sulfur species do, however, appear to be involved in much of the low temperature uranium precipitation. Assessment of the possibility of uranium transport in natural ground water is complicated because the system is generally not in overall equilibrium. For this reason, Eh measurements are of limited value. If a ground water is to be capable of reducing uranium, it must contain ions capable of reducing uranium both thermodynamically and kinetically. At present, the best candidates are reduced sulfur species.

  18. Helicopter immobilization of elk in southcentral Washington

    SciTech Connect

    McCorquodale, S.M.; Eberhardt, L.E. ); Petron, S.E. )

    1988-01-01

    Free-ranging elk are commonly immobilized for research or management by rifle-fired darts shot from a helicopter. Compounds used for this purpose have included succinylcholine chloride (succinylcholine), etorphine hydrochloride (etorphine), and xylazine hydrochloride (xylazine). To assess the efficacy of various immobilizing drugs used in helicopter applications, we darted 38 elk from a helicopter on the Arid Lands Ecology Reserve, Washington from 1983 to 1987. We used either succinylcholine, etorphine hydrochloride, or xylazine hydrochloride a primary immobilants. Unsuccessful immobilizations were most common in elk darted with succinylcholine. Yohimbine was used to reverse xylazine immobilizations. The use of xylazine and yohimbine provides an efficient, cost-effective alternative to etorphine, diprenorphine immobilization and reversal in elk while increasing handler safety. Etorphine appeared to be the best immobilant when extended pain-producing procedures (such as surgical telemetry implantation) are planned because it induced the longest and deepest anesthesia. When the potential to lose contact with darted animals exist, we believe succinylcholine may be the preferred immobilant because of rapid, spontaneous recovery.

  19. Plutonium Immobilization Can Loading Equipment Review

    SciTech Connect

    Kriikku, E.; Ward, C.; Stokes, M.; Randall, B.; Steed, J.; Jones, R.; Hamilton, L.

    1998-05-01

    This report lists the operations required to complete the Can Loading steps on the Pu Immobilization Plant Flow Sheets and evaluates the equipment options to complete each operation. This report recommends the most appropriate equipment to support Plutonium Immobilization Can Loading operations.

  20. Protein immobilization strategies for protein biochips.

    PubMed

    Rusmini, Federica; Zhong, Zhiyuan; Feijen, Jan

    2007-06-01

    In the past few years, protein biochips have emerged as promising proteomic and diagnostic tools for obtaining information about protein functions and interactions. Important technological innovations have been made. However, considerable development is still required, especially regarding protein immobilization, in order to fully realize the potential of protein biochips. In fact, protein immobilization is the key to the success of microarray technology. Proteins need to be immobilized onto surfaces with high density in order to allow the usage of small amount of sample solution. Nonspecific protein adsorption needs to be avoided or at least minimized in order to improve detection performances. Moreover, full retention of protein conformation and activity is a challenging task to be accomplished. Although a large number of review papers on protein biochips have been published in recent years, few have focused on protein immobilization technology. In this review, current protein immobilization strategies, including physical, covalent, and bioaffinity immobilization for the fabrication of protein biochips, are described. Particular consideration has been given to oriented immobilization, also referred to as site-specific immobilization, which is believed will improve homogeneous surface covering and accessibility of the active site.

  1. Immobilized Lactase in the Biochemistry Laboratory

    NASA Astrophysics Data System (ADS)

    Allison, Matthew J.; Bering, C. Larry

    1998-10-01

    Immobilized enzymes have many practical applications. They may be used in clinical, industrial, and biotechnological laboratories and in many clinical diagnostic kits. For educational purposes, use of immobilized enzymes can easily be taught at the undergraduate or even secondary level. We have developed an immobilized enzyme experiment that combines many practical techniques used in the biochemistry laboratory and fits within a three-hour time frame. In this experiment, lactase from over-the-counter tablets for patients with lactose intolerance is immobilized in polyacrylamide, which is then milled into small beads and placed into a chromatography column. A lactose solution is added to the column and the eluant is assayed using the glucose oxidase assay, available as a kit. We have determined the optimal conditions to give the greatest turnover of lactose while allowing the immobilized enzymes to be active for long periods at room temperature.

  2. Immobilized fluid membranes for gas separation

    SciTech Connect

    Liu, Wei; Canfield, Nathan L; Zhang, Jian; Li, Xiaohong Shari; Zhang, Jiguang

    2014-03-18

    Provided herein are immobilized liquid membranes for gas separation, methods of preparing such membranes and uses thereof. In one example, the immobilized membrane includes a porous metallic host matrix and an immobilized liquid fluid (such as a silicone oil) that is immobilized within one or more pores included within the porous metallic host matrix. The immobilized liquid membrane is capable of selective permeation of one type of molecule (such as oxygen) over another type of molecule (such as water). In some examples, the selective membrane is incorporated into a device to supply oxygen from ambient air to the device for electrochemical reactions, and at the same time, to block water penetration and electrolyte loss from the device.

  3. Structure-selective hot-spot Raman enhancement for direct identification and detection of trace penicilloic acid allergen in penicillin.

    PubMed

    Zhang, Liying; Jin, Yang; Mao, Hui; Zheng, Lei; Zhao, Jiawei; Peng, Yan; Du, Shuhu; Zhang, Zhongping

    2014-08-15

    Trace penicilloic acid allergen frequently leads to various fatal immune responses to many patients, but it is still a challenge to directly discriminate and detect its residue in penicillin by a chemosensing way. Here, we report that silver-coated gold nanoparticles (Au@Ag NPs) exhibit a structure-selective hot-spot Raman enhancement capability for direct identification and detection of trace penicilloic acid in penicillin. It has been demonstrated that penicilloic acid can very easily link Au@Ag NPs together by its two carboxyl groups, locating itself spontaneously at the interparticle of Au@Ag NPs to form strong Raman hot-spot. At the critical concentration inducing the nanoparticle aggregation, Raman-enhanced effect of penicilloic acid is ~60,000 folds higher than that of penicillin. In particular, the selective Raman enhancement to the two carboxyl groups makes the peak of carboxyl group at C6 of penicilloic acid appear as a new Raman signal due to the opening of β-lactam ring of penicillin. The surface-enhanced Raman scattering (SERS) nanoparticle sensor reaches a sensitive limit lower than the prescribed 1.0‰ penicilloic acid residue in penicillin. The novel strategy to examine allergen is more rapid, convenient and inexpensive than the conventional separation-based assay methods.

  4. Protein Kinase C (PkcA) of Aspergillus nidulans Is Involved in Penicillin Production

    PubMed Central

    Herrmann, Martina; Spröte, Petra; Brakhage, Axel A.

    2006-01-01

    The biosynthesis of the β-lactam antibiotic penicillin in the filamentous fungus Aspergillus nidulans is catalyzed by three enzymes that are encoded by the acvA, ipnA, and aatA genes. A variety of cis-acting DNA elements and regulatory factors form a complex regulatory network controlling these β-lactam biosynthesis genes. Regulators involved include the CCAAT-binding complex AnCF and AnBH1. AnBH1 acts as a repressor of the penicillin biosynthesis gene aatA. Until now, however, little information has been available on the signal transduction cascades leading to the transcription factors. Here we show that inhibition of protein kinase C (Pkc) activity in A. nidulans led to cytoplasmic localization of an AnBH1-enhanced green fluorescent protein (EGFP) fusion protein. Computer analysis of the genome and screening of an A. nidulans gene library revealed that the fungus possesses two putative Pkc-encoding genes, which we designated pkcA and pkcB. Only PkcA showed all the characteristic features of fungal Pkc's. Production of pkcA antisense RNA in A. nidulans led to reduced growth and conidiation in Aspergillus minimal medium, while in fermentation medium it led to enhanced expression of an aatAp-lacZ gene fusion, reduced pencillin production, and predominantly cytoplasmic localization of AnBH1. These data agree with the finding that inhibition of Pkc activity prevented nuclear localization of AnBH1-EGFP. As a result, repression of aatA expression was relieved. The involvement of Pkc in penicillin biosynthesis is also interesting in light of the fact that in the yeast Saccharomyces cerevisiae, Pkc plays a major role in maintaining cell integrity. PMID:16598003

  5. Protein kinase C (PkcA) of Aspergillus nidulans is involved in penicillin production.

    PubMed

    Herrmann, Martina; Spröte, Petra; Brakhage, Axel A

    2006-04-01

    The biosynthesis of the beta-lactam antibiotic penicillin in the filamentous fungus Aspergillus nidulans is catalyzed by three enzymes that are encoded by the acvA, ipnA, and aatA genes. A variety of cis-acting DNA elements and regulatory factors form a complex regulatory network controlling these beta-lactam biosynthesis genes. Regulators involved include the CCAAT-binding complex AnCF and AnBH1. AnBH1 acts as a repressor of the penicillin biosynthesis gene aatA. Until now, however, little information has been available on the signal transduction cascades leading to the transcription factors. Here we show that inhibition of protein kinase C (Pkc) activity in A. nidulans led to cytoplasmic localization of an AnBH1-enhanced green fluorescent protein (EGFP) fusion protein. Computer analysis of the genome and screening of an A. nidulans gene library revealed that the fungus possesses two putative Pkc-encoding genes, which we designated pkcA and pkcB. Only PkcA showed all the characteristic features of fungal Pkc's. Production of pkcA antisense RNA in A. nidulans led to reduced growth and conidiation in Aspergillus minimal medium, while in fermentation medium it led to enhanced expression of an aatAp-lacZ gene fusion, reduced pencillin production, and predominantly cytoplasmic localization of AnBH1. These data agree with the finding that inhibition of Pkc activity prevented nuclear localization of AnBH1-EGFP. As a result, repression of aatA expression was relieved. The involvement of Pkc in penicillin biosynthesis is also interesting in light of the fact that in the yeast Saccharomyces cerevisiae, Pkc plays a major role in maintaining cell integrity.

  6. Profiling of β-Lactam Selectivity for Penicillin-Binding Proteins in Streptococcus pneumoniae D39

    PubMed Central

    Kocaoglu, Ozden; Tsui, Ho-Ching T.; Winkler, Malcolm E.

    2015-01-01

    Selective fluorescent β-lactam chemical probes enable the visualization of the transpeptidase activity of penicillin-binding proteins (PBPs) at different stages of bacterial cell division. To facilitate the development of new fluorescent probes for PBP imaging, we evaluated 20 commercially available β-lactams for selective PBP inhibition in an unencapsulated derivative of the D39 strain of Streptococcus pneumoniae. Live cells were treated with β-lactam antibiotics at different concentrations and subsequently incubated with Bocillin FL (Boc-FL; fluorescent penicillin) to saturate uninhibited PBPs. Fluorophore-labeled PBPs were visualized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and fluorescence scanning. Among 20 compounds tested, carbapenems (doripenem and meropenem) were coselective for PBP1a, PBP2x, and PBP3, while six of the nine penicillin compounds were coselective for PBP2x and PBP3. In contrast, the seven cephalosporin compounds tested display variability in their PBP-binding profiles. Three cephalosporin compounds (cefoxitin, cephalexin, and cefsulodin) and the monobactam aztreonam exhibited selectivity for PBP3, while only cefuroxime (a cephalosporin) was selective for PBP2x. Treatment of S. pneumoniae cultures with a sublethal concentration of cefuroxime that inhibited 60% of PBP2x activity and less than 20% of the activity of other PBPs resulted in formation of elongated cells. In contrast, treatment of S. pneumoniae cultures with concentrations of aztreonam and cefoxitin that inhibited up to 70% of PBP3 activity and less than 30% of other PBPs resulted in no discernible morphological changes. Additionally, correlation of the MIC and IC50s for each PBP, with the exception of faropenem, amdinocillin (mecillinam), and 6-APA, suggests that pneumococcal growth inhibition is primarily due to the inhibition of PBP2x. PMID:25845878

  7. Antileptospiral activity of xanthones from Garcinia mangostana and synergy of gamma-mangostin with penicillin G

    PubMed Central

    2013-01-01

    Background Leptospirosis, one of the most widespread zoonotic infectious diseases worldwide, is caused by spirochetes bacteria of the genus Leptospira. The present study examined inhibitory activity of purified xanthones and crude extracts from Garcinia mangostana against both non-pathogenic and pathogenic leptospira. Synergy between γ-mangostin and penicillin G against leptospires was also determined. Methods Minimal inhibitory concentrations (MIC) of crude extracts and purified xanthones from G. mangostana and penicillin G for a non-pathogenic (L. biflexa serovar Patoc) and pathogenic (L. interrogans serovar Bataviae, Autumnalis, Javanica and Saigon) leptospires were determined by using broth microdilution method and alamar blue. The synergy was evaluated by calculating the fractional inhibitory concentration (FIC) index. Results The results of broth microdilution test demonstrated that the crude extract and purified xanthones from mangosteen possessed antileptospiral activities. The crude extracts were active against all five serovars of test leptospira with MICs ranging from 200 to ≥ 800 μg/ml. Among the crude extracts and purified xanthones, garcinone C was the most active compound against both of pathogenic (MIC =100 μg/ml) and non-pathogenic leptospira (MIC = 200 μg/ml). However, these MIC values were higher than those of traditional antibiotics. Combinations of γ-mangostin with penicillin G generated synergistic effect against L. interrogans serovars Bataviae, Autumnalis and Javanica (FIC = 0.52, 0.50, and 0.04, respectively) and no interaction against L. biflexa serovar Patoc (FIC =0.75). However, antagonistic activity (FIC = 4.03) was observed in L. interrogans serovar Saigon. Conclusions Crude extracts and purified xanthones from fruit pericarp of G. mangostana with significant antibacterial activity may be used to control leptospirosis. The combination of xanthone with antibiotic enhances the antileptospiral efficacy. PMID

  8. Effects of new penicillin susceptibility breakpoints for Streptococcus pneumoniae--United States, 2006-2007.

    PubMed

    2008-12-19

    Streptococcus pneumoniae (pneumococcus) is a common cause of pneumonia and meningitis in the United States. Antimicrobial resistance, which can result in pneumococcal infection treatment failure, is identified by measuring the minimum inhibitory concentration (MIC) of an antimicrobial that will inhibit pneumococcal growth. Breakpoints are MICs that define infections as susceptible (treatable), intermediate (possibly treatable with higher doses), and resistant (not treatable) to certain antimicrobials. In January 2008, after a reevaluation that included more recent clinical studies, the Clinical and Laboratory Standards Institute (CLSI) published new S. pneumoniae breakpoints for penicillin (the preferred antimicrobial for susceptible S. pneumoniae infections). To assess the potential effects of the new breakpoints on susceptibility categorization, CDC applied them to MICs of invasive pneumococcal disease (IPD) isolates collected by the Active Bacterial Core surveillance (ABCs) system at sites in 10 states during 2006-2007. This report summarizes the results of that analysis, which found that the percentage of IPD nonmeningitis S. pneumoniae isolates categorized as susceptible, intermediate, and resistant to penicillin changed from 74.7%, 15.0%, and 10.3% under the former breakpoints to 93.2%, 5.6%, and 1.2%, respectively, under the new breakpoints. Microbiology laboratories should be aware of the new breakpoints to interpret pneumococcal susceptibility accurately, and clinicians should be aware of the breakpoints to prescribe antimicrobials appropriately for pneumococcal infections. State and local health departments also should be aware of the new breakpoints because they might result in a decrease in the number of reported cases of penicillin-resistant pneumococcus.

  9. Profiling of β-lactam selectivity for penicillin-binding proteins in Streptococcus pneumoniae D39.

    PubMed

    Kocaoglu, Ozden; Tsui, Ho-Ching T; Winkler, Malcolm E; Carlson, Erin E

    2015-01-01

    Selective fluorescent β-lactam chemical probes enable the visualization of the transpeptidase activity of penicillin-binding proteins (PBPs) at different stages of bacterial cell division. To facilitate the development of new fluorescent probes for PBP imaging, we evaluated 20 commercially available β-lactams for selective PBP inhibition in an unencapsulated derivative of the D39 strain of Streptococcus pneumoniae. Live cells were treated with β-lactam antibiotics at different concentrations and subsequently incubated with Bocillin FL (Boc-FL; fluorescent penicillin) to saturate uninhibited PBPs. Fluorophore-labeled PBPs were visualized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and fluorescence scanning. Among 20 compounds tested, carbapenems (doripenem and meropenem) were coselective for PBP1a, PBP2x, and PBP3, while six of the nine penicillin compounds were coselective for PBP2x and PBP3. In contrast, the seven cephalosporin compounds tested display variability in their PBP-binding profiles. Three cephalosporin compounds (cefoxitin, cephalexin, and cefsulodin) and the monobactam aztreonam exhibited selectivity for PBP3, while only cefuroxime (a cephalosporin) was selective for PBP2x. Treatment of S. pneumoniae cultures with a sublethal concentration of cefuroxime that inhibited 60% of PBP2x activity and less than 20% of the activity of other PBPs resulted in formation of elongated cells. In contrast, treatment of S. pneumoniae cultures with concentrations of aztreonam and cefoxitin that inhibited up to 70% of PBP3 activity and less than 30% of other PBPs resulted in no discernible morphological changes. Additionally, correlation of the MIC and IC50s for each PBP, with the exception of faropenem, amdinocillin (mecillinam), and 6-APA, suggests that pneumococcal growth inhibition is primarily due to the inhibition of PBP2x. PMID:25845878

  10. Detection of relatively penicillin G-resistant Neisseria meningitidis by disk susceptibility testing.

    PubMed Central

    Campos, J; Mendelman, P M; Sako, M U; Chaffin, D O; Smith, A L; Sáez-Nieto, J A

    1987-01-01

    Beginning in 1985, relatively penicillin G-resistant (Penr) meningococci which did not produce beta-lactamase were isolated from the blood and cerebrospinal fluid of patients in Spain. We identified 16 Penr (mean MIC, 0.3 microgram/ml; range, 0.1 to 0.7 microgram/ml) and 12 penicillin-susceptible (Pens; mean MIC, less than or equal to 0.06 microgram/ml) strains of Neisseria meningitidis by the agar dilution technique using an inoculum of 10(4) CFU and questioned which disk susceptibility test would best differentiate these two populations. We compared the disk susceptibility of these strains using disks containing 2 (P2) and 10 (P10) U of penicillin G, 2 (Am2) and 10 (Am10) micrograms of ampicillin, and 1 microgram of oxacillin (OX1). We also investigated susceptibility with disks containing 30 micrograms of each of cephalothin (CF30), cefoxitin (FOX30), cefuroxime (CXM30), and cefotaxime (CTX30) and 75 micrograms of cefoperazone (CFP75) and determined by cluster analysis any correlation with the zone diameters obtained with P2 disks. Using the P2 and AM2 disks (in contrast to the P10 and AM10 disks), we correctly differentiated all the Penr from Pens isolates. In addition, the zone diameters with the P2 disk gave the best correlation with the penicillin G MIC determinations. All 16 Penr strains and 3 of 12 Pens strains showed zone diameters of 6 mm around OX1 disks, limiting the usefulness of OX1 disks. The zone diameters obtained with CF30, CXM30, and OX1 disks correlated with those obtained with the P2 disk, which suggests that these antibiotics have similar effects on these strains. In contrast, the data obtained with FOX30, CTX30, and CFP75 disks did not cluster with those obtained with the P2 disk, which suggests that there was a difference in the bacterial target or reflects their greater activity. We conclude that the P2 disk tests more readily identify Penr meningococci than do the standard P10 disk tests. PMID:3124729

  11. The interaction between ghrelin and cannabinoid systems in penicillin-induced epileptiform activity in rats.

    PubMed

    Arslan, Gokhan; Ayyildiz, Mustafa; Agar, Erdal

    2014-12-01

    The majority of experimental and clinical studies show that ghrelin and cannabinoids are potent inhibitors of epileptic activity in various models of epilepsy. A number of studies have attempted to understand the connection between ghrelin and cannabinoid signalling in the regulation of food intake. Since no data show a functional interaction between ghrelin and cannabinoids in epilepsy, we examined the relationship between these systems via penicillin-induced epileptiform activity in rats. Doses of the CB1 receptor agonist arachidonyl-2-chloroethylamide (ACEA) (2.5 and 7.5 µg), the CB1 receptor antagonist N-(piperidin-1-yl)-5-(4-iodophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3 carboxamide (AM-251) (0.25 and 0.5 µg) and ghrelin (0.5 and 1 µg) were administered intracerebroventricularly (i.c.v.) 30 minutes after the intracortical (i.c.) application of penicillin. In the interaction groups, the animals received either an effective dose of ACEA (7.5 µg, i.c.v.) or a non-effective dose of ACEA (2.5 µg, i.c.v.) or effective doses of AM-251 (0.25, 0.5 µg, i.c.v.) 10 minutes after ghrelin application. A 1 µg dose of ghrelin suppressed penicillin-induced epileptiform activity. The administration of a 0.25 µg dose of AM-251 increased the frequency of penicillin-induced epileptiform activity by producing status epilepticus-like activity. A 7.5 µg dose of ACEA decreased the frequency of epileptiform activity, whereas a non-effective dose of ACEA (2.5 µg) did not change it. Effective doses of AM-251 (0.25, 0.5 µg) reversed the ghrelin's anticonvulsant activity. The application of non-effective doses of ACEA (2.5 µg) together with ghrelin (0.5 µg) within 10 minutes caused anticonvulsant activity, which was reversed by the administration of AM-251 (0.25 µg). The electrophysiological evidence from this study suggests a possible interaction between ghrelin and cannabinoid CB1 receptors in the experimental model of epilepsy.

  12. Beta-lactamase genes of the penicillin-susceptible Bacillus anthracis Sterne strain.

    PubMed

    Chen, Yahua; Succi, Janice; Tenover, Fred C; Koehler, Theresa M

    2003-02-01

    Susceptibility to penicillin and other beta-lactam-containing compounds is a common trait of Bacillus anthracis. Beta-lactam agents, particularly penicillin, have been used worldwide to treat anthrax in humans. Nonetheless, surveys of clinical and soil-derived strains reveal penicillin G resistance in 2 to 16% of isolates tested. Bacterial resistance to beta-lactam agents is often mediated by production of one or more types of beta-lactamases that hydrolyze the beta-lactam ring, inactivating the antimicrobial agent. Here, we report the presence of two beta-lactamase (bla) genes in the penicillin-susceptible Sterne strain of B. anthracis. We identified bla1 by functional cloning with Escherichia coli. bla1 is a 927-nucleotide (nt) gene predicted to encode a protein with 93.8% identity to the type I beta-lactamase gene of Bacillus cereus. A second gene, bla2, was identified by searching the unfinished B. anthracis chromosome sequence database of The Institute for Genome Research for open reading frames (ORFs) predicted to encode beta-lactamases. We found a partial ORF predicted to encode a protein with significant similarity to the carboxy-terminal end of the type II beta-lactamase of B. cereus. DNA adjacent to the 5' end of the partial ORF was cloned using inverse PCR. bla2 is a 768-nt gene predicted to encode a protein with 92% identity to the B. cereus type II enzyme. The bla1 and bla2 genes confer ampicillin resistance to E. coli and Bacillus subtilis when cloned individually in these species. The MICs of various antimicrobial agents for the E. coli clones indicate that the two beta-lactamase genes confer different susceptibility profiles to E. coli; bla1 is a penicillinase, while bla2 appears to be a cephalosporinase. The beta-galactosidase activities of B. cereus group species harboring bla promoter-lacZ transcriptional fusions indicate that bla1 is poorly transcribed in B. anthracis, B. cereus, and B. thuringiensis. The bla2 gene is strongly expressed in B

  13. Penicillin-Binding Protein 2a of Methicillin-Resistant Staphylococcus aureus

    PubMed Central

    Fishovitz, Jennifer; Hermoso, Juan A.; Chang, Mayland

    2014-01-01

    Summary High-level resistance to β-lactam antibiotics in methicillin-resistant Staphylococcus aureus (MRSA) is due to expression of penicillin-binding protein 2a (PBP2a), a transpeptidase that catalyzes cell-wall crosslinking in the face of the challenge by β-lactam antibiotics. The activity of this protein is regulated by allostery at a site 60 Å distant from the active site, where crosslinking of cell wall takes place. This review discusses the state of knowledge on this important enzyme of cell-wall biosynthesis in MRSA. PMID:25044998

  14. Early synergistic interaction between semisynthetic penicillins and aminoglycosidic aminocyclitols against Enterobacteriaceae.

    PubMed Central

    Glew, R H; Pavuk, R A

    1983-01-01

    Time-kill curves were used to assess the relative in vitro efficacy of the early interaction of three semisynthetic penicillins with two aminoglycosides against 48 Enterobacteriaceae strains. The most efficacious combinations were piperacillin plus amikacin, which demonstrated synergism (greater than or equal to 2 logs of increased kill after 7 h of incubation) against 43 of 48 (90%) strains, and piperacillin plus gentamicin, which exhibited synergism against 25 of 48 (52%) strains. With the combinations of carbenicillin or ticarcillin plus amikacin or gentamicin, early synergistic killing was demonstrated against only 12 to 29% of the strains. PMID:6225391

  15. The interaction between ghrelin and cannabinoid systems in penicillin-induced epileptiform activity in rats.

    PubMed

    Arslan, Gokhan; Ayyildiz, Mustafa; Agar, Erdal

    2014-12-01

    The majority of experimental and clinical studies show that ghrelin and cannabinoids are potent inhibitors of epileptic activity in various models of epilepsy. A number of studies have attempted to understand the connection between ghrelin and cannabinoid signalling in the regulation of food intake. Since no data show a functional interaction between ghrelin and cannabinoids in epilepsy, we examined the relationship between these systems via penicillin-induced epileptiform activity in rats. Doses of the CB1 receptor agonist arachidonyl-2-chloroethylamide (ACEA) (2.5 and 7.5 µg), the CB1 receptor antagonist N-(piperidin-1-yl)-5-(4-iodophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3 carboxamide (AM-251) (0.25 and 0.5 µg) and ghrelin (0.5 and 1 µg) were administered intracerebroventricularly (i.c.v.) 30 minutes after the intracortical (i.c.) application of penicillin. In the interaction groups, the animals received either an effective dose of ACEA (7.5 µg, i.c.v.) or a non-effective dose of ACEA (2.5 µg, i.c.v.) or effective doses of AM-251 (0.25, 0.5 µg, i.c.v.) 10 minutes after ghrelin application. A 1 µg dose of ghrelin suppressed penicillin-induced epileptiform activity. The administration of a 0.25 µg dose of AM-251 increased the frequency of penicillin-induced epileptiform activity by producing status epilepticus-like activity. A 7.5 µg dose of ACEA decreased the frequency of epileptiform activity, whereas a non-effective dose of ACEA (2.5 µg) did not change it. Effective doses of AM-251 (0.25, 0.5 µg) reversed the ghrelin's anticonvulsant activity. The application of non-effective doses of ACEA (2.5 µg) together with ghrelin (0.5 µg) within 10 minutes caused anticonvulsant activity, which was reversed by the administration of AM-251 (0.25 µg). The electrophysiological evidence from this study suggests a possible interaction between ghrelin and cannabinoid CB1 receptors in the experimental model of epilepsy. PMID

  16. Biochemical characterization of penicillin-resistant and -sensitive penicillin-binding protein 2x transpeptidase activities of Streptococcus pneumoniae and mechanistic implications in bacterial resistance to beta-lactam antibiotics.

    PubMed Central

    Zhao, G; Yeh, W K; Carnahan, R H; Flokowitsch, J; Meier, T I; Alborn, W E; Becker, G W; Jaskunas, S R

    1997-01-01

    To understand the biochemical basis of resistance of bacteria to beta-lactam antibiotics, we purified a penicillin-resistant penicillin-binding protein 2x (R-PBP2x) and a penicillin-sensitive PBP2x (S-PBP2x) enzyme of Streptococcus pneumoniae and characterized their transpeptidase activities, using a thioester analog of stem peptides as a substrate. A comparison of the k(cat)/Km values for the two purified enzymes (3,400 M(-1) s(-1) for S-PBP2x and 11.2 M(-1) s(-1) for R-PBP2x) suggests that they are significantly different kinetically. Implications of this finding are discussed. We also found that the two purified enzymes did not possess a detectable level of beta-lactam hydrolytic activity. Finally, we show that the expression levels of both PBP2x enzymes were similar during different growth phases. PMID:9244281

  17. Uranium Immobilization in Wetland Soils

    NASA Astrophysics Data System (ADS)

    Jaffe, Peter R.; Koster van Groos, Paul G.; Li, Dien; Chang, Hyun-Shik; Seaman, John C.; Kaplan, Daniel I.; Peacock, Aaron D.; Scheckel, Kirk

    2014-05-01

    stronger for the mesocosms with the higher Fe(II) load. Analysis via XANES showed that a fraction (up to ~1/3) of uranium was reduced to U(IV), for mesocosms operated under low iron loading, indicating that iron cycling in the rhizosphere also results in uranium reduction and immobilization. For mesocosms operating under the higher iron loading, the fraction of uranium immobilized as U(IV) was much lower, indicating that uranium co-precipitation with iron might have been the dominant immobilization process. In parallel to these mesocosm experiments, dialysis samplers have been deployed at the Savannah River National Laboratory near a creek with uranium contamination, to determine dissolved species, including Fe(II) and U(VI) in these wetland soils and their seasonal variability. The results show that there is a strong seasonal variability in dissolved iron and uranium, indicating a strong immobilization during the growing season, which is consistent with the mesocosm experimental results that the rhizosphere iron and uranium cycling are closely linked.

  18. Plutonium Immobilization Can Loading Concepts

    SciTech Connect

    Kriikku, E.; Ward, C.; Stokes, M.; Randall, B.; Steed, J.; Jones, R.; Hamilton, L.; Rogers, L.; Fiscus, J.; Dyches, G.

    1998-05-01

    The Plutonium Immobilization Facility will encapsulate plutonium in ceramic pucks and seal the pucks inside welded cans. Remote equipment will place these cans in magazines and the magazines in a Defense Waste Processing Facility (DWPF) canister. The DWPF will fill the canister with glass for permanent storage. This report discusses five can loading conceptual designs and the lists the advantages and disadvantages for each concept. This report identifies loading pucks into cans and backfilling cans with helium as the top priority can loading development areas. The can loading welder and cutter are very similar to the existing Savannah River Site (SRS) FB-Line bagless transfer welder and cutter and thus they are a low priority development item.

  19. Plutonium Immobilization Project Baseline Formulation

    SciTech Connect

    Ebbinghaus, B.

    1999-02-01

    A key milestone for the Immobilization Project (AOP Milestone 3.2a) in Fiscal Year 1998 (FY98) is the definition of the baseline composition or formulation for the plutonium ceramic form. The baseline formulation for the plutonium ceramic product must be finalized before the repository- and plant-related process specifications can be determined. The baseline formulation that is currently specified is given in Table 1.1. In addition to the baseline formulation specification, this report provides specifications for two alternative formulations, related compositional specifications (e.g., precursor compositions and mixing recipes), and other preliminary form and process specifications that are linked to the baseline formulation. The preliminary specifications, when finalized, are not expected to vary tremendously from the preliminary values given.

  20. [Progress in co-immobilization of multiple enzymes].

    PubMed

    Wang, Jindan; Zhang, Guangya

    2015-04-01

    Enzyme immobilization is the core technology of biocatalysis. Over the past few decades, enzyme immobilization research mainly focused on single enzyme immobilization. In recent years, multi-enzyme immobilization attracts more and more attention as it could increase the local concentration of reaction and improve the reaction yield. In this review, a summary of the recent progress, together with our research, is presented. Special emphasis is placed on four methods in multi-enzymes co-immobilization, namely, the nonspecific covalent co-immobilization, the nonspecific non-covalent co-immobilization, the non-covalent encapsulation co-immobilized and the site specificity co-immobilized. Finally, some industrial uses of immobilized multi-enzymes were addressed and the application prospect of multi-enzyme immobilization was highlighted.

  1. Biochemistry and Comparative Genomics of SxxK Superfamily Acyltransferases Offer a Clue to the Mycobacterial Paradox: Presence of Penicillin-Susceptible Target Proteins versus Lack of Efficiency of Penicillin as Therapeutic Agent

    PubMed Central

    Goffin, Colette; Ghuysen, Jean-Marie

    2002-01-01

    The bacterial acyltransferases of the SxxK superfamily vary enormously in sequence and function, with conservation of particular amino acid groups and all-α and α/β folds. They occur as independent entities (free-standing polypeptides) and as modules linked to other polypeptides (protein fusions). They can be classified into three groups. The group I SxxK d,d-acyltransferases are ubiquitous in the bacterial world. They invariably bear the motifs SxxK, SxN(D), and KT(S)G. Anchored in the plasma membrane with the bulk of the polypeptide chain exposed on the outer face of it, they are implicated in the synthesis of wall peptidoglycans of the most frequently encountered (4→3) type. They are inactivated by penicillin and other β-lactam antibiotics acting as suicide carbonyl donors in the form of penicillin-binding proteins (PBPs). They are components of a morphogenetic apparatus which, as a whole, controls multiple parameters such as shape and size and allows the bacterial cells to enlarge and duplicate their particular pattern. Class A PBP fusions comprise a glycosyltransferase module fused to an SxxK acyltransferase of class A. Class B PBP fusions comprise a linker, i.e., protein recognition, module fused to an SxxK acyltransferase of class B. They ensure the remodeling of the (4→3) peptidoglycans in a cell cycle-dependent manner. The free-standing PBPs hydrolyze d,d peptide bonds. The group II SxxK acyltransferases frequently have a partially modified bar code, but the SxxK motif is invariant. They react with penicillin in various ways and illustrate the great plasticity of the catalytic centers. The secreted free-standing PBPs, the serine β-lactamases, and the penicillin sensors of several penicillin sensory transducers help the d,d-acyltransferases of group I escape penicillin action. The group III SxxK acyltransferases are indistinguishable from the PBP fusion proteins of group I in motifs and membrane topology, but they resist penicillin. They are

  2. Susceptibility of Recently Collected Spanish Pneumococci Nonsusceptible to Oral Penicillin from Serotypes Not Included in the 7-Valent Conjugate Vaccine▿

    PubMed Central

    Fenoll, Asunción; Aguilar, Lorenzo; Giménez, María-José; Vicioso, María-Dolores; Robledo, Olga; Granizo, Juan-José; Coronel, Pilar

    2010-01-01

    The susceptibilities of pneumococci recently collected (up to June 2009) in Spain (500 isolates nonsusceptible to oral penicillin and 150 susceptible isolates) from serotypes not included in the conjugate vaccine were determined. Most nonsusceptible isolates (53.6%) belonged to serotype 19A. Susceptibility rates in serotype 19A penicillin-intermediate (n = 201)/penicillin-resistant (n = 67) isolates were <33%/≤6.0% (erythromycin and oral cephalosporins with defined breakpoints), 85.1%/11.9% (amoxicillin), and 96.0%/52.2% (cefotaxime), respectively. Low susceptibility to common oral β-lactams was also found in serotypes 11A (95.5% susceptibility to cefotaxime and erythromycin) and 35B. PMID:20308373

  3. [Cross allergy between penicillins and other beta lactam antibiotics--the risk is much less than previously thought].

    PubMed

    Tängden, Thomas; Furebring, Mia; Löwdin, Elisabeth; Werner, Sonja

    2015-02-03

    Severe IgE-mediated allergic reactions to penicillins are rare but might be fatal. Because some studies demonstrated a high risk of cross-sensitivity to cephalosporins and carbapenems it has been recommended to avoid these antibiotics in patients with suspected hypersensitivity to penicillins. However, recent studies and analyses conclude that the risk of cross-reactivity was overestimated in the earlier studies and that it is in fact very low for parenteral cephalosporins and perhaps even negligible for carbapenems. The new knowledge has implications for the choice of therapy for bacterial infections in patients with a history of penicillin hypersensitivity, because alternative antibiotic regimens are often inferior to beta-lactam antibiotics. The aim of the present review is to present existing knowledge on cross-sensitivity between beta-lactams, as well as to discuss the management of patients with suspected allergic reactions to these antibiotics.

  4. Metabolic Responses of Bacterial Cells to Immobilization.

    PubMed

    Żur, Joanna; Wojcieszyńska, Danuta; Guzik, Urszula

    2016-01-01

    In recent years immobilized cells have commonly been used for various biotechnological applications, e.g., antibiotic production, soil bioremediation, biodegradation and biotransformation of xenobiotics in wastewater treatment plants. Although the literature data on the physiological changes and behaviour of cells in the immobilized state remain fragmentary, it is well documented that in natural settings microorganisms are mainly found in association with surfaces, which results in biofilm formation. Biofilms are characterized by genetic and physiological heterogeneity and the occurrence of altered microenvironments within the matrix. Microbial cells in communities display a variety of metabolic differences as compared to their free-living counterparts. Immobilization of bacteria can occur either as a natural phenomenon or as an artificial process. The majority of changes observed in immobilized cells result from protection provided by the supports. Knowledge about the main physiological responses occurring in immobilized cells may contribute to improving the efficiency of immobilization techniques. This paper reviews the main metabolic changes exhibited by immobilized bacterial cells, including growth rate, biodegradation capabilities, biocatalytic efficiency and plasmid stability. PMID:27455220

  5. Effects of yeast immobilization on bioethanol production.

    PubMed

    Borovikova, Diana; Scherbaka, Rita; Patmalnieks, Aloizijs; Rapoport, Alexander

    2014-01-01

    The current study evaluated a newer method, which includes a dehydration step, of immobilizing Saccharomyces cerevisiae L-77 and S. cerevisiae L-73 onto hydroxylapatite and chamotte ceramic supports. The efficiency of cell immobilization on chamotte was significantly higher than hydroxylapatite. Immobilized yeast preparations were investigated for their ethanol-producing capabilities. The glucose concentration in a fermentation medium was 100 mg/mL. Immobilized preparations produced the same amount of ethanol (48 ± 0.5 mg/mL) as free cells after 36 H of fermentation. During the early stages of fermentation, immobilized yeast cells produced ethanol at a higher rate than free cells. Yeast preparations immobilized on both supports (hydroxylapatite and chamotte) were successfully used in six sequential batch fermentations without any loss of activity. The chamotte support was more stable in the fermentation medium during these six cycles of ethanol production. In addition to the high level of ethanol produced by cells immobilized on chamotte, the stability of this support and its low cost make it a promising material for biotechnologies associated with ethanol production.

  6. Immobilization and characterization of a thermostable lipase.

    PubMed

    Song, Chongfu; Sheng, Liangquan; Zhang, Xiaobo

    2013-12-01

    Lipases have found a number of commercial applications. However, thermostable lipase immobilized on nanoparticle is not extensively characterized. In this study, a recombinant thermostable lipase (designated as TtL) from Thermus thermophilus WL was expressed in Escherichia coli and immobilized onto 3-APTES-modified Fe3O4@SiO2 supermagnetic nanoparticles. Based on analyses with tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis, X-ray diffraction, transmission electron microscopy, and vibrating sample magnetometer observation, the diameter of immobilized lipase nanoparticle was 18.4 (± 2.4) nm, and its saturation magnetization value was 52.3 emu/g. The immobilized lipase could be separated from the reaction medium rapidly and easily in a magnetic field. The biochemical characterizations revealed that, comparing with the free one, the immobilized lipase exhibited better resistance to temperature, pH, metal ions, enzyme inhibitors, and detergents. The K m value for the immobilized TtL (2.56 mg/mL) was found to be lower than that of the free one (3.74 mg/mL), showing that the immobilization improved the affinity of lipase for its substrate. In addition, the immobilized TtL exhibited good reusability. It retained more than 79.5 % of its initial activity after reusing for 10 cycles. Therefore, our study presented that the possibility of the efficient reuse of the thermostable lipase immobilized on supermagnetic nanoparticles made it attractive from the viewpoint of practical application. PMID:23748908

  7. Protein hydrolysis by immobilized and stabilized trypsin.

    PubMed

    Marques, Daniela; Pessela, Benavides C; Betancor, Lorena; Monti, Rubens; Carrascosa, Alfonso V; Rocha-Martin, Javier; Guisán, Jose M; Fernandez-Lorente, Gloria

    2011-01-01

    The preparation of novel immobilized and stabilized derivatives of trypsin is reported here. The new derivatives preserved 80% of the initial catalytic activity toward synthetic substrates [benzoyl-arginine p-nitroanilide (BAPNA)] and were 50,000-fold more thermally stable than the diluted soluble enzyme in the absence of autolysis. Trypsin was immobilized on highly activated glyoxyl-Sepharose following a two-step immobilization strategy: (a) first, a multipoint covalent immobilization at pH 8.5 that only involves low pK(a) amino groups (e.g., those derived from the activation of trypsin from trypsinogen) is performed and (b) next, an additional alkaline incubation at pH 10 is performed to favor an intense, additional multipoint immobilization between the high concentration of proximate aldehyde groups on the support surface and the high pK(a) amino groups at the enzyme surface region that participated in the first immobilization step. Interestingly, the new, highly stable trypsin derivatives were also much more active in the proteolysis of high molecular weight proteins when compared with a nonstabilized derivative prepared on CNBr-activated Sepharose. In fact, all the proteins contained a cheese whey extract had been completely proteolyzed after 6 h at pH 9 and 50°C, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Under these experimental conditions, the immobilized biocatalysts preserve more than 90% of their initial activity after 20 days. Analysis of the three-dimensional (3D) structure of the best immobilized trypsin derivative showed a surface region containing two amino terminal groups and five lysine (Lys) residues that may be responsible for this novel and interesting immobilization and stabilization. Moreover, this region is relatively far from the active site of the enzyme, which could explain the good results obtained for the hydrolysis of high-molecular weight proteins.

  8. Investigations on the role of CH…O interactions and its impact on stability and specificity of penicillin binding proteins.

    PubMed

    Lavanya, P; Ramaiah, Sudha; Singh, Harpeet; Bahadur, Renu; Anbarasu, Anand

    2015-10-01

    Penicillin binding proteins are recognized as important antibacterial targets because of their crucial role in the cell wall synthesis of bacteria. Alteration in the binding site of penicillin binding proteins is one of the major problems for beta lactam antibiotics to exert its effect. In the present study the influence of CH…O interactions in the conformational stability of penicillin binding proteins were analyzed in both Gram positive and Gram negative bacteria. CH…O interactions constitute about 20 to 25% of total hydrogen bonds and act as an important driving force in ligand selectivity. From our analysis we observed a total of 13,398 CH…O interactions in Gram positive bacteria and 10,855 CH…O interactions in Gram negative bacteria. It was interesting to observe that CH…O interactions were higher in Gram positive bacteria than in Gram negative bacteria, which augurs well for the discrepancy in cell wall of the bacteria. CH…O interactions are classified into four types depending on the interaction of acceptor residues with the back bone or side chain of CH groups. From our results we observed that major contribution to penicillin binding proteins was observed from side chain atoms of donor residues and back bone atoms of acceptor residues [SM CH…O] in both Gram positive and Gram negative bacteria. Conformational preference of Gram positive bacteria indicated that amino acids lacking side chain and the cyclized amino acids preferred to be in turn regions, whereas aromatic amino acids dominated in Gram negative bacteria. Our analysis gives detailed information about the principles involved in the conformational stability of penicillin binding proteins and the results will be useful for researchers exploring penicillin binding proteins. PMID:26298489

  9. Seasonal Variation in Penicillin Use in Mexico and Brazil: Analysis of the Impact of Over-the-Counter Restrictions

    PubMed Central

    Santa-Ana-Tellez, Yared; Mantel-Teeuwisse, Aukje K.; Leufkens, Hubert G. M.

    2014-01-01

    During 2010, Mexico and Brazil implemented policies to enforce existing laws of restricting over-the-counter sales of antibiotics. We determined if the enforcement led to more appropriate antibiotic use by measuring changes in seasonal variation of penicillin use. We used retail quarterly sales data in defined daily doses per 1,000 inhabitant-days (DDD/TID) from IMS Health from the private sector in Mexico and Brazil from the first quarter of 2007 to the first quarter of 2013. This database contains information on volume of antibiotics sold in retail pharmacies using information from wholesalers. We used interrupted time-series models controlling for external factors with the use of antihypertensives with interaction terms to assess changes in trend, level, and variation in use between quarters for total penicillin use and by active substance. The most used penicillin was amoxicillin, followed by amoxicillin-clavulanic acid and ampicillin (minimal use in Brazil). Before the restrictions, the seasonal variation in penicillin use was 1.1 DDD/TID in Mexico and 0.8 DDD/TID in Brazil. In Mexico, we estimated a significant decrease in the seasonal variation of 0.4 DDD/TID after the restriction, mainly due to changes in seasonal variation of amoxicillin and ampicillin. In Brazil, the seasonal variation did not change significantly, overall and in the breakdown by individual active substances. For Mexico, inappropriate penicillin use may have diminished after the restrictions were enforced. For Brazil, increasing use and no change in seasonal variation suggest that further efforts are needed to reduce inappropriate penicillin use. PMID:25313222

  10. Penicillin-resistant, ampicillin-susceptible Enterococcus faecalis of hospital origin: pbp4 gene polymorphism and genetic diversity.

    PubMed

    Conceição, Natália; da Silva, Lucas Emanuel Pinheiro; Darini, Ana Lúcia da Costa; Pitondo-Silva, André; de Oliveira, Adriana Gonçalves

    2014-12-01

    Despite the spread of penicillin-resistant, ampicillin-susceptible Enterococcus faecalis (PRASEF) isolates in diverse countries, the mechanisms leading to this unusual resistance phenotype have not yet been investigated. The aim of this study was to evaluate whether polymorphism in the pbp4 gene is associated with penicillin resistance in PRASEF isolates and to determine their genetic diversity. E. faecalis isolates were recovered from different clinical specimens of hospitalized patients from February 2006 to June 2010. The β-lactam minimal inhibitory concentrations (MICs) were determined by E-test®. The PCR-amplified pbp4 gene was sequenced with an automated sequencer. The genetic diversities of the isolates were established by PFGE (pulsed-field gel electrophoresis) and MLST (multilocus sequencing typing). Seventeen non-producing β-lactamase PRASEF and 10 penicillin-susceptible, ampicillin-susceptible E. faecalis (PSASEF) strains were analyzed. A single-amino-acid substitution (Asp-573→Glu) in the penicillin-binding domain was significantly found in all PRASEF isolates by sequencing of the pbp4 gene but not in the penicillin-susceptible isolates. In contrast to the PSASEF isolates, a majority of the PRASEFs had similar PFGE profiles. Six representative PRASEF isolates were resolved by MLST into ST9 and ST524 and belong to the globally dispersed clonal complex 9 (CC9). In conclusion, it appears quite likely that the amino acid alteration (Asp-573→Glu) found in the PBP4 of the Brazilian PRASEF isolates may account for their reduced susceptibility to penicillin, although other resistance mechanisms remain to be investigated.

  11. Seasonal variation in penicillin use in Mexico and Brazil: analysis of the impact of over-the-counter restrictions.

    PubMed

    Santa-Ana-Tellez, Yared; Mantel-Teeuwisse, Aukje K; Leufkens, Hubert G M; Wirtz, Veronika J

    2015-01-01

    During 2010, Mexico and Brazil implemented policies to enforce existing laws of restricting over-the-counter sales of antibiotics. We determined if the enforcement led to more appropriate antibiotic use by measuring changes in seasonal variation of penicillin use. We used retail quarterly sales data in defined daily doses per 1,000 inhabitant-days (DDD/TID) from IMS Health from the private sector in Mexico and Brazil from the first quarter of 2007 to the first quarter of 2013. This database contains information on volume of antibiotics sold in retail pharmacies using information from wholesalers. We used interrupted time-series models controlling for external factors with the use of antihypertensives with interaction terms to assess changes in trend, level, and variation in use between quarters for total penicillin use and by active substance. The most used penicillin was amoxicillin, followed by amoxicillin-clavulanic acid and ampicillin (minimal use in Brazil). Before the restrictions, the seasonal variation in penicillin use was 1.1 DDD/TID in Mexico and 0.8 DDD/TID in Brazil. In Mexico, we estimated a significant decrease in the seasonal variation of 0.4 DDD/TID after the restriction, mainly due to changes in seasonal variation of amoxicillin and ampicillin. In Brazil, the seasonal variation did not change significantly, overall and in the breakdown by individual active substances. For Mexico, inappropriate penicillin use may have diminished after the restrictions were enforced. For Brazil, increasing use and no change in seasonal variation suggest that further efforts are needed to reduce inappropriate penicillin use.

  12. Plutonium immobilization feed batching system concept report

    SciTech Connect

    Erickson, S.

    2000-07-19

    The Plutonium Immobilization Facility will encapsulate plutonium in ceramic pucks and seal the pucks inside welded cans. Remote equipment will place these cans in magazines and the magazines in a Defense Waste Processing Facility (DWPF) canister. The DWPF will fill the canister with high level waste glass for permanent storage. Feed batching is one of the first process steps involved with first stage plutonium immobilization. It will blend plutonium oxide powder before it is combined with other materials to make pucks. This report discusses the Plutonium Immobilization feed batching process preliminary concept, batch splitting concepts, and includes a process block diagram, concept descriptions, a preliminary equipment list, and feed batching development areas.

  13. Subfamily-specific adaptations in the structures of two penicillin-binding proteins from Mycobacterium tuberculosis

    DOE PAGES

    Prigozhin, Daniil M.; Krieger, Inna V.; Huizar, John P.; Mavrici, Daniela; Waldo, Geoffrey S.; Hung, Li -Wei; Sacchettini, James C.; Terwilliger, Thomas C.; Alber, Tom; Mayer, Claudine

    2014-12-31

    Beta-lactam antibiotics target penicillin-binding proteins including several enzyme classes essential for bacterial cell-wall homeostasis. To better understand the functional and inhibitor-binding specificities of penicillin-binding proteins from the pathogen, Mycobacterium tuberculosis, we carried out structural and phylogenetic analysis of two predicted D,D-carboxypeptidases, Rv2911 and Rv3330. Optimization of Rv2911 for crystallization using directed evolution and the GFP folding reporter method yielded a soluble quadruple mutant. Structures of optimized Rv2911 bound to phenylmethylsulfonyl fluoride and Rv3330 bound to meropenem show that, in contrast to the nonspecific inhibitor, meropenem forms an extended interaction with the enzyme along a conserved surface. Phylogenetic analysis shows thatmore » Rv2911 and Rv3330 belong to different clades that emerged in Actinobacteria and are not represented in model organisms such as Escherichia coli and Bacillus subtilis. Clade-specific adaptations allow these enzymes to fulfill distinct physiological roles despite strict conservation of core catalytic residues. The characteristic differences include potential protein-protein interaction surfaces and specificity-determining residues surrounding the catalytic site. Overall, these structural insights lay the groundwork to develop improved beta-lactam therapeutics for tuberculosis.« less

  14. Growth of soil bacteria, on penicillin and neomycin, not previously exposed to these antibiotics.

    PubMed

    Zhang, Qichun; Dick, Warren A

    2014-09-15

    There is growing evidence that bacteria, in the natural environment (e.g. the soil), can exhibit naturally occurring resistance/degradation against synthetic antibiotics. Our aim was to assess whether soils, not previously exposed to synthetic antibiotics, contained bacterial strains that were not only antibiotic resistant, but could actually utilize the antibiotics for energy and nutrients. We isolated 19 bacteria from four diverse soils that had the capability of growing on penicillin and neomycin as sole carbon sources up to concentrations of 1000 mg L(-1). The 19 bacterial isolates represent a diverse set of species in the phyla Proteobacteria (84%) and Bacteroidetes (16%). Nine antibiotic resistant genes were detected in the four soils but some of these genes (i.e. tetM, ermB, and sulI) were not detected in the soil isolates indicating the presence of unculturable antibiotic resistant bacteria. Most isolates that could subsist on penicillin or neomycin as sole carbon sources were also resistant to the presence of these two antibiotics and six other antibiotics at concentrations of either 20 or 1000 mg L(-1). The potentially large and diverse pool of antibiotic resistant and degradation genes implies ecological and health impacts yet to be explored and fully understood. PMID:24956077

  15. New penicillin-producing Penicillium species and an overview of section Chrysogena.

    PubMed

    Houbraken, J; Frisvad, J C; Seifert, K A; Overy, D P; Tuthill, D M; Valdez, J G; Samson, R A

    2012-12-01

    Species classified in Penicillium sect. Chrysogena are primary soil-borne and the most well-known members are P. chrysogenum and P. nalgiovense. Penicillium chrysogenum has received much attention because of its role in the production on penicillin and as a contaminant of indoor environments and various food and feedstuffs. Another biotechnologically important species is P. nalgiovense, which is used as a fungal starter culture for the production of fermented meat products. Previous taxonomic studies often had conflicting species circumscriptions. Here, we present a multigene analysis, combined with phenotypic characters and extrolite data, demonstrating that sect. Chrysogena consists of 18 species. Six of these are newly described here (P. allii-sativi, P. desertorum, P. goetzii, P. halotolerans, P. tardochrysogenum, P. vanluykii) and P. lanoscoeruleum was found to be an older name for P. aethiopicum. Each species produces a unique extrolite profile. The species share phenotypic characters, such as good growth on CYA supplemented with 5 % NaCl, ter- or quarterverticillate branched conidiophores and short, ampulliform phialides (< 9 μm). Conidial colours, production of ascomata and ascospores, shape and ornamentation of conidia and growth rates on other agar media are valuable for species identification. Eight species (P. allii-sativi, P. chrysogenum, P. dipodomyis, P. flavigenum, P. nalgiovense, P. rubens, P. tardochrysogenum and P. vanluykii) produce penicillin in culture. PMID:23606767

  16. Growth of soil bacteria, on penicillin and neomycin, not previously exposed to these antibiotics.

    PubMed

    Zhang, Qichun; Dick, Warren A

    2014-09-15

    There is growing evidence that bacteria, in the natural environment (e.g. the soil), can exhibit naturally occurring resistance/degradation against synthetic antibiotics. Our aim was to assess whether soils, not previously exposed to synthetic antibiotics, contained bacterial strains that were not only antibiotic resistant, but could actually utilize the antibiotics for energy and nutrients. We isolated 19 bacteria from four diverse soils that had the capability of growing on penicillin and neomycin as sole carbon sources up to concentrations of 1000 mg L(-1). The 19 bacterial isolates represent a diverse set of species in the phyla Proteobacteria (84%) and Bacteroidetes (16%). Nine antibiotic resistant genes were detected in the four soils but some of these genes (i.e. tetM, ermB, and sulI) were not detected in the soil isolates indicating the presence of unculturable antibiotic resistant bacteria. Most isolates that could subsist on penicillin or neomycin as sole carbon sources were also resistant to the presence of these two antibiotics and six other antibiotics at concentrations of either 20 or 1000 mg L(-1). The potentially large and diverse pool of antibiotic resistant and degradation genes implies ecological and health impacts yet to be explored and fully understood.

  17. Promoter Identification and Transcription Analysis of Penicillin-Binding Protein Genes in Streptococcus pneumoniae R6

    PubMed Central

    Peters, Katharina; Pipo, Julia; Schweizer, Inga; Hakenbeck, Regine

    2016-01-01

    Penicillin-binding proteins (PBPs) are membrane-associated enzymes, which are involved in the last two steps of peptidoglycan biosynthesis, and some of them are key players in cell division. Furthermore, they are targets of β-lactams, the most widely used antibiotics. Nevertheless, very little is known about the expression and regulation of PBP genes. Using transcriptional mapping, we now determined the promoter regions of PBP genes from the laboratory strain Streptococcus pneumoniae R6 and examined the expression profile of these six promoters. The extended −10 region is highly conserved and complies with a σA-type promoter consensus sequence. In contrast, the −35 region is poorly conserved, indicating the possibility for differential PBP regulation. All PBP promoters were constitutively expressed and highly active during the exponential and early stationary growth phase. However, the individual expression of PBP promoters varied approximately fourfold, with pbp1a being the highest and pbp3 the lowest. Furthermore, the deletion of one nucleotide in the spacer region of the PBP3 promoter reduced pbp3 expression ∼10-fold. The addition of cefotaxime above the minimal inhibitory concentration (MIC) did not affect PBP expression in the penicillin-sensitive R6 strain. No evidence for regulation of S. pneumoniae PBP genes was obtained. PMID:27409661

  18. Highly sensitive bacterial susceptibility test against penicillin using parylene-matrix chip.

    PubMed

    Park, Jong-Min; Kim, Jo-Il; Song, Hyun-Woo; Noh, Joo-Yoon; Kang, Min-Jung; Pyun, Jae-Chul

    2015-09-15

    This work presented a highly sensitive bacterial antibiotic susceptibility test through β-lactamase assay using Parylene-matrix chip. β-lactamases (EC 3.5.2.6) are an important family of enzymes that confer resistance to β-lactam antibiotics by catalyzing the hydrolysis of these antibiotics. Here we present a highly sensitive assay to quantitate β-lactamase-mediated hydrolysis of penicillin into penicilloic acid. Typically, MALDI-TOF mass spectrometry has been used to quantitate low molecular weight analytes and to discriminate them from noise peaks of matrix fragments that occur at low m/z ratios (m/z<500). The β-lactamase assay for the Escherichia coli antibiotic susceptibility test was carried out using Parylene-matrix chip and MALDI-TOF mass spectrometry. The Parylene-matrix chip was successfully used to quantitate penicillin (m/z: [PEN+H](+)=335.1 and [PEN+Na](+)=357.8) and penicilloic acid (m/z: [PA+H](+)=353.1) in a β-lactamase assay with minimal interference of low molecular weight noise peaks. The β-lactamase assay was carried out with an antibiotic-resistant E. coli strain and an antibiotic-susceptible E. coli strain, revealing that the minimum number of E. coli cells required to screen for antibiotic resistance was 1000 cells for the MALDI-TOF mass spectrometry/Parylene-matrix chip assay.

  19. Subfamily-Specific Adaptations in the Structures of Two Penicillin-Binding Proteins from Mycobacterium tuberculosis

    PubMed Central

    Prigozhin, Daniil M.; Krieger, Inna V.; Huizar, John P.; Mavrici, Daniela; Waldo, Geoffrey S.; Hung, Li-Wei; Sacchettini, James C.; Terwilliger, Thomas C.; Alber, Tom

    2014-01-01

    Beta-lactam antibiotics target penicillin-binding proteins including several enzyme classes essential for bacterial cell-wall homeostasis. To better understand the functional and inhibitor-binding specificities of penicillin-binding proteins from the pathogen, Mycobacterium tuberculosis, we carried out structural and phylogenetic analysis of two predicted D,D-carboxypeptidases, Rv2911 and Rv3330. Optimization of Rv2911 for crystallization using directed evolution and the GFP folding reporter method yielded a soluble quadruple mutant. Structures of optimized Rv2911 bound to phenylmethylsulfonyl fluoride and Rv3330 bound to meropenem show that, in contrast to the nonspecific inhibitor, meropenem forms an extended interaction with the enzyme along a conserved surface. Phylogenetic analysis shows that Rv2911 and Rv3330 belong to different clades that emerged in Actinobacteria and are not represented in model organisms such as Escherichia coli and Bacillus subtilis. Clade-specific adaptations allow these enzymes to fulfill distinct physiological roles despite strict conservation of core catalytic residues. The characteristic differences include potential protein-protein interaction surfaces and specificity-determining residues surrounding the catalytic site. Overall, these structural insights lay the groundwork to develop improved beta-lactam therapeutics for tuberculosis. PMID:25551456

  20. Effects of penicillin and erythromycin on adherence of invasive and noninvasive isolates of Streptococcus pyogenes to laminin.

    PubMed

    Šmitran, Aleksandra; Vuković, Dragana; Gajić, Ina; Marinković, Jelena; Ranin, Lazar

    2015-08-01

    This study investigated the possible relationship between the invasiveness of group A Streptococcus (GAS) strains and their abilities to adhere to laminin and assessed the effects of subinhibitory concentrations of penicillin and erythromycin on the ability of GAS to adhere to laminin. The adherence of noninvasive and highly invasive isolates of GAS to laminin was significantly higher than the adherence displayed by isolates of low invasiveness. Antibiotic treatment caused significant reductions in adherence to laminin in all three groups of strains. Penicillin was more successful in reducing the adherence abilities of the tested GAS strains than erythromycin.

  1. Neisseria meningitidis C:2b:P1.2,5 with Intermediate Resistance to Penicillin, Portugal

    PubMed Central

    Dias, Ricardo; Ferreira, Eugénia

    2004-01-01

    For 1 year, serogroup, serotype, serosubtype, and penicillin susceptibility of meningococci circulating in various regions in Portugal were evaluated. Most frequent phenotypes were B:4:P1.15 (13.4%) and C:2b:P1.2,5 (75.9%), which are also common in Spain. Overall, 27.5% of C:2b:P1.2,5 strains showed intermediate resistance to penicillin. Laboratory-based surveillance of meningococcal infection in Portugal provides important information to assess the adequacy of public health measures. PMID:15109429

  2. [A case of mucosa-associated lymphoid tissue lymphoma with penicillin allergy successfully treated with levofloxacin, minomycin and rabeprazole].

    PubMed

    Konno, Tomoko; Motoori, Shigeatsu; Iwamoto, Nozomi; Miyazawa, Tomoe; Saito, Shigeyo; Kitagawa, Naoko; Saisho, Hiromitsu; Furuse, Junji; Itabashi, Masayuki

    2010-10-01

    A 52-year-old Japanese woman was referred to our Institute because of Helicobacter pylori(H. pylori)-positive gastric mucosa-associated lymphoid tissue(MALT)lymphoma. Since she had a penicillin allergy, we could not eradicate H. pylori using the standard triple therapy including amoxicillin. Additionally, H. pylori was resistant to both clarithromycin and metronidazole. So she was treated with minomycin (MINO), levofloxacin (LVFX), and rabeprazole (RPZ) based on a drug sensitivity test. MINO+LVFX+RPZ appear to be a promising, appropriate, and well-tolerated eradication regimen for H. pylori demonstrating resistance to both clarithromycin and metronidazole, and for patients who are allergic to penicillin.

  3. Anticoagulant and vasodilator therapy for Nicolau syndrome following intramuscular benzathine penicillin injection in a 4 year old boy.

    PubMed

    Alkan Bozkaya, Tijen; Demirel, Gamze; Ormeci, Tugrul; Al, Serdar; Çakar, Engin; Tastekin, Ayhan; Turkoglu, Halil

    2016-06-01

    Nicolau syndrome (NS) is a rare complication of intramuscular, intraarticular or subcutaneous injection of particular drugs leading to ischemic necrosis of the surrounding skin, soft tissue and muscular tissue. Benzathine penicilin one of the most widely used antibiotic for upper respiratory tract infections and has been rarely reported to cause NS. Here we describe a 4 year old boy with diagnosis of NS after the injection of benzathine penicillin who was successfuly treated with unfractionized heparin (enoxaparine) and pentoxifylline. The practitioners should pay attention for unnecessary use of benzathine penicillin to avoid from probable complications.

  4. Application of kidney inhibition swab tests to evaluate penicillin-G residues in sow tissues and body fluids following intramuscular injection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Kidney inhibition swab (KIS) tests, recently adapted by the US FSIS for antibiotics on-site screening, were employed to evaluate the depletion of penicillin-G residues from kidney, liver, muscle, serum, and urine of sows after intramuscular (IM) penicillin-G procaine administration. Sows (n=130; 22...

  5. Synthesis of gold nanoparticles on the surface of pyrolytic graphite using penicillin as a stabilizing reagent and the catalytic oxidation of α-naphthylamine

    NASA Astrophysics Data System (ADS)

    Song, Y. Z.; Song, Y.; Cheng, Z. P.; Zhou, J. F.; Wei, C.

    2013-01-01

    Electrochemical synthesis of gold nanoparticles on the surface of pyrolytic graphite using penicillin as a stabilizing reagent was proposed. The gold nanoparticles were characterized by scanning electron microscopy, cyclic voltammetry, IR spectra, UV spectra, and powder X-ray diffraction spectra. The electro-chemical catalysis of penicillin for α-naphthylamine was demonstrated.

  6. In silico analysis of different generation β lactams antibiotics with penicillin binding protein-2 of Neisseria meningitidis for curing meningococcal disease.

    PubMed

    Tripathi, Vijay; Tripathi, Pooja; Srivastava, Navita; Gupta, Dwijendra

    2014-12-01

    Neisseria meningitidis is a gram negative, diplococcic pathogen responsible for the meningococcal disease and fulminant septicemia. Penicillin-binding proteins-2 (PBPs) is crucial for the cell wall biosynthesis during cell proliferation of N. meningitidis and these are the target for β-lactam antibiotics. For many years penicillin has been recognized as the antibiotic for meningococcal disease but the meningococcus has seemed to be antibiotic resistance. In the present work we have verified the molecular interaction of Penicillin binding protein-2 N. meningitidis to different generation of β-lactam antibiotics and concluded that the third generation of β-lactam antibiotics shows efficient binding with Penicillin binding protein-2 of N. meningitidis. On the basis of binding efficiency and inhibition constant, ceftazidime emerged as the most efficient antibiotic amongst the other advanced β-lactam antibiotics against Penicillin-binding protein-2 of N. meningitidis.

  7. Immobilization of Rocky Flats Graphite Fines Residue

    SciTech Connect

    Rudisill, T.S.

    1999-04-06

    The development of the immobilization process for graphite fines has proceeded through a series of experimental programs. The experimental procedures and results from each series of experiments are discussed in this report.

  8. Plutonium Immobilization Bagless Transfer Can Size Evaluation

    SciTech Connect

    Kriikku, E.; Stokes, M.; Rogers, L.; Ward, C.

    1998-02-01

    This report identifies and documents the most appropriate bagless transfer can size to support Plutonium Immobilization Can Loading operations. Also, this report considers can diameter, can wall thickness, and can length.

  9. Mapping of the gene for a major penicillin-binding protein to a genetically conserved region of the Bacillus subtilis chromosome and conservation of the protein among related species of Bacillus.

    PubMed Central

    Buchanan, C E; Gustafson, A

    1991-01-01

    Penicillin-binding protein 5 is the most abundant penicillin-binding protein in the vegetative membranes of Bacillus subtilis and accounts for 95% of the D,D-carboxypeptidase activity of the cell. The structural gene for penicillin-binding protein 5 was mapped to a genetically conserved region near guaB at 0 degrees on the B. subtilis chromosome, and immunoassays revealed that there is conservation of this major penicillin-binding protein among related species. Images PMID:1900282

  10. IgE to penicillins with different specificities can be identified by a multiepitope macromolecule: Bihaptenic penicillin structures and IgE specificities.

    PubMed

    Ariza, A; Barrionuevo, E; Mayorga, C; Montañez, M I; Perez-Inestrosa, E; Ruiz-Sánchez, A; Rodríguez-Guéant, R M; Fernández, T D; Guéant, J L; Torres, M J; Blanca, M

    2014-04-01

    Quantitation of specific IgE by immunoassay is a recommended in vitro test for the diagnosis of immediate hypersensitivity reactions to betalactams (BLs), particularly when skin test results are negative. IgE antibodies that recognize the common nuclear structure of all BLs or the specific side chain structure can be mainly distinguished by immunoassays. The aim of this study was to develop an immunoassay system to detect IgE antibodies with different specificities. Cellulose discs conjugated with benzylpenicillin (BP), amoxicillin (AX) or both drugs, with poly-l-lysine (PLL) as carrier molecule, were used as solid phases in the radioallergosorbent test (RAST). Direct and inhibition radioimmunoassay studies were made to verify the structures recognized by serum IgE antibodies from penicillin-allergic patients. Our results indicated that the addition of both haptens did not decrease the capacity to capture IgE when serum specific to either BP or AX was used, at least in terms of sensitivity. In addition, the inclusion of two haptens improved significantly the levels of IgE detection in patients who recognized both BP and AX. Therefore, the use of a solid phase with a carrier molecule conjugated with two determinants (AX and BP) is helpful to recognize IgE antibodies against either of these determinants and is useful for screening sera with different specificities.

  11. Immobilization Technologies in Probiotic Food Production

    PubMed Central

    Mitropoulou, Gregoria; Nedovic, Viktor; Goyal, Arun; Kourkoutas, Yiannis

    2013-01-01

    Various supports and immobilization/encapsulation techniques have been proposed and tested for application in functional food production. In the present review, the use of probiotic microorganisms for the production of novel foods is discussed, while the benefits and criteria of using probiotic cultures are analyzed. Subsequently, immobilization/encapsulation applications in the food industry aiming at the prolongation of cell viability are described together with an evaluation of their potential future impact, which is also highlighted and assessed. PMID:24288597

  12. Differences between two feline epilepsy models in sleep and waking state disorders, state dependency of seizures and seizure susceptibility: amygdala kindling interferes with systemic penicillin epilepsy.

    PubMed

    Shouse, M N

    1987-01-01

    The objective of the study was to determine whether contemporary feline models of petit mal (systemic penicillin epilepsy) or temporal lobe epilepsy (amygdala kindling) resemble human seizure disorders with respect to disturbances of sleep and waking states, the state dependency of seizures, and transference of seizure susceptibility. These variables were examined in 6-h polygraphic recordings before and during exposure to both seizure models in 24 cats; 12 cats had intramuscular (i.m.) injections of 300,000 or 400,000 IU/kg of penicillin prior to kindling, and 12 were kindled before penicillin challenge. Results were as follows. First, penicillin increased light slow wave sleep (SWS) and drowsiness, during which spike-wave (SW) activity was maximal. Generalized tonic-clonic convulsions (GTCs) occurred predominantly in drowsiness after awakening from SWS. Second, kindling produced more deep SWS than did penicillin; susceptibility to kindled GTCs peaked during deep SWS, especially in transition to rapid eye movement sleep (REM). Third, penicillin did not influence subsequent sleep disorders or seizure susceptibility during kindling; kindling interfered with penicillin-induced GTCs, SW activity, and sleep disorders. Collectively, the findings suggest distinct state disorders and state-dependent seizure profiles in the two models. These differences parallel human analogues and may have contributed to the transference results. Kindling is a chronic model with persistent sleep and seizure abnormalities that differ from and may have discouraged penicillin epilepsy. Penicillin is an acute model with transient state and seizure disorders, a fact that may account for the absence of penicillin transference to kindling.

  13. Ceramification: A plutonium immobilization process

    SciTech Connect

    Rask, W.C.; Phillips, A.G.

    1996-05-01

    This paper describes a low temperature technique for stabilizing and immobilizing actinide compounds using a combination process/storage vessel of stainless steel, in which measured amounts of actinide nitrate solutions and actinide oxides (and/or residues) are systematically treated to yield a solid article. The chemical ceramic process is based on a coating technology that produces rare earth oxide coatings for defense applications involving plutonium. The final product of this application is a solid, coherent actinide oxide with process-generated encapsulation that has long-term environmental stability. Actinide compounds can be stabilized as pure materials for ease of re-use or as intimate mixtures with additives such as rare earth oxides to increase their degree of proliferation resistance. Starting materials for the process can include nitrate solutions, powders, aggregates, sludges, incinerator ashes, and others. Agents such as cerium oxide or zirconium oxide may be added as powders or precursors to enhance the properties of the resulting solid product. Additives may be included to produce a final product suitable for use in nuclear fuel pellet production. The process is simple and reduces the time and expense for stabilizing plutonium compounds. It requires a very low equipment expenditure and can be readily implemented into existing gloveboxes. The process is easily conducted with less associated risk than proposed alternative technologies.

  14. Immobilization of Fast Reactor First Cycle Raffinate

    SciTech Connect

    Langley, K. F.; Partridge, B. A.; Wise, M.

    2003-02-26

    This paper describes the results of work to bring forward the timing for the immobilization of first cycle raffinate from reprocessing fuel from the Dounreay Prototype Fast Reactor (PFR). First cycle raffinate is the liquor which contains > 99% of the fission products separated from spent fuel during reprocessing. Approximately 203 m3 of raffinate from the reprocessing of PFR fuel is held in four tanks at the UKAEA's site at Dounreay, Scotland. Two methods of immobilization of this high level waste (HLW) have been considered: vitrification and cementation. Vitrification is the standard industry practice for the immobilization of first cycle raffinate, and many papers have been presented on this technique elsewhere. However, cementation is potentially feasible for immobilizing first cycle raffinate because the heat output is an order of magnitude lower than typical HLW from commercial reprocessing operations such as that at the Sellafield site in Cumbria, England. In fact, it falls within the upper end of the UK definition of intermediate level waste (ILW). Although the decision on which immobilization technique will be employed has yet to be made, initial development work has been undertaken to identify a suitable cementation formulation using inactive simulant of the raffinate. An approach has been made to the waste disposal company Nirex to consider the disposability of the cemented product material. The paper concentrates on the process development work that is being undertaken on cementation to inform the decision making process for selection of the immobilization method.

  15. Surface cell immobilization within perfluoroalkoxy microchannels

    NASA Astrophysics Data System (ADS)

    Stojkovič, Gorazd; Krivec, Matic; Vesel, Alenka; Marinšek, Marjan; Žnidaršič-Plazl, Polona

    2014-11-01

    Perfluoroalkoxy (PFA) is one of the most promising materials for the fabrication of cheap, solvent resistant and reusable microfluidic chips, which have been recently recognized as effective tools for biocatalytic process development. The application of biocatalysts significantly depends on efficient immobilization of enzymes or cells within the reactor enabling long-term biocatalyst use. Functionalization of PFA microchannels by 3-aminopropyltriethoxysilane (ATPES) and glutaraldehyde was used for rapid preparation of microbioreactors with surface-immobilized cells. X-ray photoelectron spectroscopy and scanning electron microscopy were used to accurately monitor individual treatment steps and to select conditions for cell immobilization. The optimized protocol for Saccharomyces cerevisiae immobilization on PFA microchannel walls comprised ethanol surface pretreatment, 4 h contacting with 10% APTES aqueous solution, 10 min treatment with 1% glutaraldehyde and 20 min contacting with cells in deionized water. The same protocol enabled also immobilization of Escherichia coli, Pseudomonas putida and Bacillus subtilis cells on PFA surface in high densities. Furthermore, the developed procedure has been proved to be very efficient also for surface immobilization of tested cells on other materials that are used for microreactor fabrication, including glass, polystyrene, poly (methyl methacrylate), polycarbonate, and two olefin-based polymers, namely Zeonor® and Topas®.

  16. Hyperalgesia in an immobilized rat hindlimb: effect of treadmill exercise using non-immobilized limbs.

    PubMed

    Chuganji, Sayaka; Nakano, Jiro; Sekino, Yuki; Hamaue, Yohei; Sakamoto, Junya; Okita, Minoru

    2015-01-01

    Cast immobilization of limbs causes hyperalgesia, which is a decline of the threshold of mechanical and thermal mechanical stimuli. The immobilization-induced hyperalgesia (IIH) can disturb rehabilitation and activities of daily living in patients with orthopedic disorders. However, it is unclear what therapeutic and preventive approaches can be used to alleviate IIH. Exercise that activates the descending pain modulatory system may be effective for IIH. The purpose of this study was to investigate the effects of treadmill exercise during the immobilization period, using the non-immobilized limbs, on IIH. Thirty-six 8-week-old Wistar rats were randomly divided into (1) control, (2) immobilization (Im), and (3) immobilization and treadmill exercise (Im+Ex) groups. In the Im and Im+Ex groups, the right ankle joints of each rat were immobilized in full plantar flexion with a plaster cast for an 8-week period. In the Im+Ex group, treadmill exercise (15 m/min, 30 min/day, 5 days/week) was administered during the immobilization period while the right hindlimb was kept immobilized. Mechanical hyperalgesia was measured using von Frey filaments every week. To investigate possible activation of the descending pain modulatory system, beta-endorphin expression levels in hypothalamus and midbrain periaqueductal gray were analyzed. Although IIH clearly occurred in the Im group, the hyperalgesia was partially but significantly reduced in the Im+Ex group. Beta-endorphin, which is one of the endogenous opioids, was selectively increased in the hypothalamus and midbrain periaqueductal gray of the Im+Ex group. Our data suggest that treadmill running using the non-immobilized limbs reduces the amount of hyperalgesia induced in the immobilized limb even if it is not freed. This ameliorating effect might be due to the descending pain modulatory system being activated by upregulation of beta-endorphin in the brain. PMID:25304541

  17. Evaluation of penicillin G residues by kidney inhibition swab tests in sow body fluids and tissues following intramuscular injection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In 2011, the USDA-Food Safety and Inspection Service (FSIS) changed the method used for screening swine tissues for antimicrobial residues to the Kidney Inhibition Swab (KIS(TM)) from the Fast Antimicrobial Screen Test. A high dose of penicillin G procaine relative to a label dose is commonly used ...

  18. Depletion of penicillin G residues in heavy sows after intramuscular injection. Part II: Application of kidney inhibition swab tests

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sows (n = 126; 228 ± 30.1 kg) were administered daily IM doses of penicillin G procaine (33 000 IU/kg bw; 5× the label dose) for 3 consecutive days using three different administration patterns. Within treatment, six sows each were slaughtered on withdrawal day 5, 10, 15, 20, 25, 32, and 39. Tissues...

  19. Development of the radiation-resistant strain of Moraxella osloensis and effect of penicillin G on its growth

    NASA Astrophysics Data System (ADS)

    Lim, Sangyong; Yun, Hyejeong; Joe, Minho; Kim, Dongho

    2009-07-01

    A series of repeated exposures to γ-radiation with intervening outgrowth of survivors was used to develop radioresistant cultures of Moraxella osloensis that have been recognized as potential pathogenic microorganism. The D10 value of the radiation-resistant strain, 5.903±0.006 kGy, was increased by four-fold compared to the parent wild-type strain, 1.637±0.004 kGy. Since most strains of M. osloensis are sensitive to penicillin, we have surveyed the sensitivity of radiation-resistant strain to this antibiotic. When the optical density was monitored after the addition of penicillin G, the radioresistant strain appeared to be more resistant to only a low concentration of penicillin G (0.5 U/ml) than the parent strain. Interestingly, however, there was no apparent difference in the number of viable cells between both strains. Scanning electron microscope data showed that the resistance cells were generally larger than the parent cells, suggesting that this increase in size may cause a higher optical density of radioresistant cells. In conclusion, radiation mutation does not affect the penicillin resistance of M. osloensis.

  20. Evaluation of penicillin G residues by kidney inhibition swab tests in sow body fluids and tissues following intramuscular injection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In 2011, the USDA-Food Safety and Inspection Service (FSIS) changed the method used for screening swine tissues for antimicrobial residues from the Fast Antimicrobial Screen Test to the Kidney Inhibition Swab (KIS(TM)). Here, we describe the use of KIS(TM) test for the detection of penicillin G res...

  1. Increasing penicillin and trimethoprim-sulfamethoxazole resistance in nasopharyngeal Streptococcus pneumoniae isolates from Guatemalan children, 2001-2006

    PubMed Central

    Dueger, Erica L.; Asturias, Edwin J.; Matheu, Jorge; Gordillo, Remei; Torres, Olga; Halsey, Neal

    2008-01-01

    Objectives We determined nasopharyngeal colonization rates and antibiotic resistance patterns of Streptococcus pneumoniae isolated from Guatemalan children and determined risk factors for colonization and antibiotic nonsusceptibility. Methods Isolates were obtained from Guatemala City children 5 to 60 months of age attending public and private outpatient clinics and daycare centers during August 2001–June 2002 and outpatient clinics during November 2005–February 2006. Minimal inhibitory concentrations of penicillin, trimethoprim-sulfamethoxazole (TMS), cefotaxime, and erythromycin were determined using E-test. Results The overall nasopharyngeal colonization rate for S. pneumoniae was 59.1%. From 2001/2 to 2005/6 TMS nonsusceptibility increased from 42.4% to 60.8% (p<0.05) in public clinics and from 51.4% to 84.0% (p=0.009) in private clinics and penicillin nonsusceptibility increased from 1.5% to 33.3% in public clinics (p<0.001). Reported antibiotic use was not strictly associated with nonsusceptibility to that same antibiotic. Resistance to three or four antibiotics increased in public clinics from 2001/2 (0%) to 2005/6 (10.7%; p<0.001). Risk factors for nasopharyngeal colonization with penicillin- or TMS-nonsusceptible S. pneumoniae were low family income, daycare center attendance, and recent penicillin use. Conclusions Increasing antibiotic nonsusceptibility rates in nasopharyngeal S. pneumoniae isolates from Guatemalan children reflect worldwide trends. Policies encouraging more judicious use of TMS should be considered. PMID:18035570

  2. 75 FR 35044 - Notice of Approval of a Supplemental New Animal Drug Application; Penicillin G Procaine Suspension

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-21

    ... new animal drug application (NADA) filed by Norbrook Laboratories, Ltd. The supplemental NADA provides... 6JP, Northern Ireland, filed a supplement to NADA 065-010 for use of NOROCILLIN (penicillin G procaine... supplemental NADA is approved as of April 23, 2010. In accordance with the freedom of information provisions...

  3. The Impact of Reporting a Prior Penicillin Allergy on the Treatment of Methicillin-Sensitive Staphylococcus aureus Bacteremia

    PubMed Central

    Shenoy, Erica S.; Huang, Mingshu; Kuhlen, James L.; Ware, Winston A.; Parker, Robert A.; Walensky, Rochelle P.

    2016-01-01

    Background Methicillin-sensitive Staphylococcus aureus (MSSA) bacteremia is a morbid infection with mortality benefit from receipt of parenteral β-lactam therapy. A substantial portion of MSSA bacteremia patients report penicillin allergy, but infrequently have true allergy. Objective To determine the frequency and predictors of optimal and adequate therapy in patients with MSSA bacteremia. Design Retrospective cohort. Participants Adult inpatients with MSSA bacteremia, January 2009 through October 2013. Main Measures The primary measure was a trial of optimal therapy (OT), defined as ≥3 inpatient days or discharge on any first-line agents (nafcillin, oxacillin, cefazolin, or penicillin G, if susceptible). The secondary measure was completion of adequate therapy (AT), defined as ≥10 inpatient days or discharge on an agent appropriate for MSSA bacteremia. Data were electronically gathered with key variables manually validated through chart review. Log-binomial regression models were used to determine the frequency and predictors of outcomes. Key Results Of 456 patients, 346 (76%) received a trial of OT. Patients reporting penicillin allergy (13%) were less likely to receive OT trial than those without penicillin allergy (47% vs. 80%, p <0.001). Adjusting for other factors, penicillin allergy was the largest negative predictor of OT trial (RR 0.64 [0.49, 0.83]). Infectious Disease (ID) consultation was the largest positive predictor of OT trial across all patients (RR 1.34 [1.14, 1.57]). Allergy/Immunology consultation was the single most important predictor of OT trial among patients reporting penicillin allergy (RR 2.33 [1.44, 3.77]). Of 440 patients, 391 (89%) completed AT, with ID consultation the largest positive predictor of the outcome (RR 1.28 [1.15, 1.43]). Conclusions Nearly 25% of patients with MSSA bacteremia did not receive OT trial and about 10% did not receive AT completion. Reported penicillin allergy reduced, and ID consult increased, the

  4. Screening of antibiotics and chemical analysis of penicillin residue in fresh milk and traditional dairy products in Oyo state, Nigeria

    PubMed Central

    Olatoye, Isaac Olufemi; Daniel, Oluwayemisi Folashade; Ishola, Sunday Ayobami

    2016-01-01

    Background and Aim: There are global public health and economic concerns on chemical residues in food of animal origin. The use of antibiotics in dairy cattle for the treatment of diseases such as mastitis has contributed to the presence of residues in dairy products. Penicillin residues as low as 1 ppb can lead to allergic reactions and shift of resistance patterns in microbial population as well as interfere with the processing of several dairy products. Antibiotic monitoring is an essential quality control measure in safe milk production. This study was aimed at determining antibiotic residue contamination and the level of penicillin in dairy products from Fulani cattle herds in Oyo State. Materials and Methods: The presence of antibiotic residues in 328 samples of fresh milk, 180 local cheese (wara), and 90 fermented milk (nono) from Southwest, Nigeria were determined using Premi® test kit (R-Biopharm AG, Germany) followed by high-performance liquid chromatography analysis of penicillin-G residue. Results: Antibiotic residues were obtained in 40.8%, 24.4% and 62.3% fresh milk, wara and nono, respectively. Penicillin-G residue was also detected in 41.1% fresh milk, 40.2% nono and 24.4% wara at mean concentrations of 15.22±0.61, 8.24±0.50 and 7.6±0.60 μg/L with 39.3%, 36.7% and 21.1%, respectively, containing penicillin residue above recommended Codex maximum residue limit (MRL) of 5 μg/L in dairy. There was no significant difference between the mean penicillin residues in all the dairy products in this study. Conclusion: The results are of food safety concern since the bulk of the samples and substantial quantities of dairy products in Oyo state contained violative levels of antibiotic residues including penicillin residues in concentrations above the MRL. This could be due to indiscriminate and unregulated administration of antibiotics to dairy cattle. Regulatory control of antibiotic use, rapid screening of milk and dairy farmers’ extension education

  5. Mineral induction by immobilized phosphoproteins

    NASA Technical Reports Server (NTRS)

    Saito, T.; Arsenault, A. L.; Yamauchi, M.; Kuboki, Y.; Crenshaw, M. A.

    1997-01-01

    Dentin phosphoproteins are thought to have a primary role in the deposition of mineral on the collagen of dentin. In this study we determined the type of binding between collagen and phosphoproteins necessary for mineral formation onto collagen fibrils and whether the phosphate esters are required. Bovine dentin phosphophoryn or phosvitin from egg yolk were immobilized on reconstituted skin type I collagen fibrils by adsorption or by covalent cross-linking. In some samples the ester phosphate was removed from the covalently cross-linked phosphoproteins by treatment with acid phosphatase. All samples were incubated at 37 degrees C in metastable solutions that do not spontaneously precipitate. Reconstituted collagen fibrils alone did not induce mineral formation. The phosphoproteins adsorbed to the collagen fibrils desorbed when the mineralization medium was added, and mineral was not induced. The mineral induced by the cross-linked phosphoproteins was apatite, and the crystals were confined to the surface of the collagen fibrils. With decreasing medium saturation the time required for mineral induction increased. The interfacial tensions calculated for apatite formation by either phosphoprotein cross-linked to collagen were about the same as that for phosphatidic acid liposomes and hydroxyapatite. This similarity in values indicates that the nucleation potential of these highly phosphorylated surfaces is about the same. It is concluded that phosphoproteins must be irreversibly bound to collagen fibrils for the mineralization of the collagen network in solutions that do not spontaneously precipitate. The phosphate esters of phosphoproteins are required for mineral induction, and the carboxylate groups are not sufficient.

  6. Penicillin and Cell Wall Synthesis: A Study of Bacillus cereus by Electron Microscopy

    PubMed Central

    Highton, Peter J.; Hobbs, D. G.

    1972-01-01

    The changes in wall structure of a penicillinase micro-constitutive strain of Bacillus cereus (569/H/24), on exposure to penicillin, and after its removal by addition of penicillinase, have suggested the following model for the growth of the walls of these cylindrical cells. Longitudinal extension is by addition of material to a large and continuously increasing number of growing points uniformly distributed over the cylindrical surface. Addition is only in the longitudinal direction so that the cell diameter remains constant. Cross walls grow by addition to their inner edge, and on completion the two new rounded ends of the daughter cells are formed by splitting at the outer edge and continued addition at the center. The ends are conserved. Images PMID:4110923

  7. Rethinking antibiotic research and development: World War II and the penicillin collaborative.

    PubMed

    Quinn, Roswell

    2013-03-01

    Policy leaders and public health experts may be overlooking effective ways to stimulate innovative antibiotic research and development. I analyzed archival resources concerning the US government's efforts to produce penicillin during World War II, which demonstrate how much science policy can differ from present approaches. By contrast to current attempts to invigorate commercial participation in antibiotic development, the effort to develop the first commercially produced antibiotic did not rely on economic enticements or the further privatization of scientific resources. Rather, this extremely successful scientific and, ultimately, commercial endeavor was rooted in government stewardship, intraindustry cooperation, and the open exchange of scientific information. For policymakers facing the problem of stimulating antibiotic research and development, the origins of the antibiotic era offer a template for effective policy solutions that concentrate primarily on scientific rather than commercial goals.

  8. Interaction of penicillin G with the human erythrocyte membrane and models.

    PubMed

    Suwalsky, M; Villena, F; Aguilar, F; Sotomayor, C P

    1996-01-01

    Penicillin G (PEN) is a widely used antibiotic whose mechanism of action is related to the interference with the synthesis of bacteria cell wall. In order to evaluate its perturbing effect upon human cell membranes PEN was made to interact with human erythrocytes, isolated resealed human erythrocyte membranes and molecular models. The latter were multibilayers of the phospholipids dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE) as well as DMPC large unilamellar vesicles. These studies were performed by scanning electron microscopy, fluorescence spectroscopy and X-ray diffraction methods. The observed results coincide in that PEN did not exert any significant effect upon the structures of the red cell membrane neither on its molecular models. This is in agreement with its reported lack of major toxicity and hematological reactions. PMID:8639231

  9. Rethinking Antibiotic Research and Development: World War II and the Penicillin Collaborative

    PubMed Central

    2013-01-01

    Policy leaders and public health experts may be overlooking effective ways to stimulate innovative antibiotic research and development. I analyzed archival resources concerning the US government’s efforts to produce penicillin during World War II, which demonstrate how much science policy can differ from present approaches. By contrast to current attempts to invigorate commercial participation in antibiotic development, the effort to develop the first commercially produced antibiotic did not rely on economic enticements or the further privatization of scientific resources. Rather, this extremely successful scientific and, ultimately, commercial endeavor was rooted in government stewardship, intraindustry cooperation, and the open exchange of scientific information. For policymakers facing the problem of stimulating antibiotic research and development, the origins of the antibiotic era offer a template for effective policy solutions that concentrate primarily on scientific rather than commercial goals. PMID:22698031

  10. Inhibition of proliferation of cervical and leukemic cancer cells by penicillin G.

    PubMed

    Banerjee, Aditya; Dahiya, Meetu; Anand, M T; Kumar, Sudhir

    2013-01-01

    Cancer, despite all the efforts, still causes one in five deaths worldwide. Surgery, chemotherapy and radiotherapy provide inadequate protection and instead affect normal cells along with cancer cells. The search for cancer cures from natural products (plants and animals) has been practice for over a decade and the use of purified chemical to treat cancer still continues. Several studies have been undertaken during last three decades to find the anti-cancerous property of various plant extract and toxins secreted by animals and micro-organism. These lead to the discovery of several promising molecule having anticancer activity, some of which are in clinical trial and may emerged to be a potential future drug in cancer therapy. In this study we have used penicillin to evaluate its anti-cancer activity. It shown significant effects at cellular and molecular levels against growth of HeLa and K562 cell lines. PMID:23679330

  11. Penicillin susceptibility breakpoints for Streptococcus pneumoniae and their effect on susceptibility categorisation in Germany (1997-2013).

    PubMed

    Imöhl, M; Reinert, R R; Tulkens, P M; van der Linden, M

    2014-11-01

    Continuous nationwide surveillance of invasive pneumococcal disease (IPD) was conducted in Germany. From July 1, 1997, to June 30, 2013, data on penicillin susceptibility were available for 20,437 isolates. 2,790 of these isolates (13.7 %) originate from patients with meningitis and 17,647 isolates (86.3 %) are from non-meningitis cases. A slight decline in isolates susceptible at 0.06 and 0.12 μg/ml can be noticed over the years. Overall, 89.1 % of the isolates had minimum inhibitory concentrations (MICs) of ≤0.015 μg/ml. In 2012/2013, the first three isolates of Streptococcus pneumoniae with MICs of 8 μg/ml were found. The application of different guidelines with other MIC breakpoints for the interpretation of penicillin resistance leads to differences in susceptibility categorisation. According to the pre-2008 Clinical and Laboratory Standards Institute (CLSI) interpretive criteria, 5.3 % of isolates overall were intermediate and 1.4 % were resistant to penicillin. Application of the 2008-2014 CLSI interpretive criteria resulted in 7.6 % resistance among meningitis cases and 0.5 % intermediate resistance in non-meningitis cases. Referring to the 2009-2014 European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoints, 7.6 % of the isolates in the meningitis group were resistant to penicillin. In the non-meningitis group, 6.1 % of the isolates were intermediate and 0.5 % were resistant. These differences should be kept in mind when surveillance studies on pneumococcal penicillin resistance are compared.

  12. Removal of penicillin G from aqueous phase by Fe+3-TiO2/UV-A process

    PubMed Central

    2014-01-01

    Background Anomalous use of antibiotics and their entrance into the environment have increased concerns around the world. These compounds enter the environment through an incomplete metabolism and a considerable amount of them cannot be removed using conventional wastewater treatment. Therefore, the main objectives of this research are evaluation of the feasibility of using ultraviolet radiation (UV-A) and fortified nanoparticles of titanium dioxide (TiO2) doped with Fe+3 to remove penicillin G (PENG) from aqueous phase and determining the optimum conditions for maximum removal efficiency. Results The results showed that the maximum removal rate of penicillin G occurred in acidic pH (pH = 3) in the presence of 90 mg/L Fe+3-TiO2 catalyst. In addition, an increase in pH caused a decrease in penicillin G removal rate. As the initial concentration of penicillin G increased, the removal rate of antibiotic decreased. Moreover, due to the effect of UV on catalyst activation in Fe+3-TiO2/UV-A process, a significant increase was observed in the rate of antibiotic removal. All of the variables in the process had a statistically significant effect (p < 0.001). Conclusion The findings demonstrated that the antibiotic removal rate increased by decreasing pH and increasing the amount of catalyst and contact time. In conclusion, Fe+3-TiO2/UV-A process is an appropriate method for reducing penicillin G in polluted water resources. PMID:24598354

  13. The thioredoxin system of Penicillium chrysogenum and its possible role in penicillin biosynthesis.

    PubMed Central

    Cohen, G; Argaman, A; Schreiber, R; Mislovati, M; Aharonowitz, Y

    1994-01-01

    Penicillium chrysogenum is an important producer of penicillin antibiotics. A key step in their biosynthesis is the oxidative cyclization of delta-(L-alpha-aminoadipyl)-L-cysteinyl-D-valine (ACV) to isopenicillin N by the enzyme isopenicillin N synthase (IPNS). bis-ACV, the oxidized disulfide form of ACV is, however, not a substrate for IPNS. We report here the characterization of a broad-range disulfide reductase from P. chrysogenum that efficiently reduces bis-ACV to the thiol monomer. When coupled in vitro with IPNS, it converts bis-ACV to isopenicillin N and may therefore play a role in penicillin biosynthesis. The disulfide reductase consists of two protein components, a 72-kDa NADPH-dependent reductase, containing two identical subunits, and a 12-kDa general disulfide reductant. The latter reduces disulfide bonds in low-molecular-weight compounds and in proteins. The genes coding for the reductase system were cloned and sequenced. Both possess introns. A comparative analysis of their predicted amino acid sequences showed that the 12-kDa protein shares 26 to 60% sequence identity with thioredoxins and that the 36-kDa protein subunit shares 44 to 49% sequence identity with the two known bacterial thioredoxin reductases. In addition, the P. chrysogenum NADPH-dependent reductase is able to accept thioredoxin as a substrate. These results establish that the P. chrysogenum broad-range disulfide reductase is a member of the thioredoxin family of oxidoreductases. This is the first example of the cloning of a eucaryotic thioredoxin reductase gene. Images PMID:8106340

  14. The penicillin regulator PENR1 of Aspergillus nidulans is a HAP-like transcriptional complex.

    PubMed

    Litzka, O; Papagiannopolous, P; Davis, M A; Hynes, M J; Brakhage, A A

    1998-02-01

    In Aspergillus nidulans, a DNA-binding complex, PENR1, was shown to bind to two CCAAT-box-containing DNA elements located in the promoter regions of the bidirectionally oriented penicillin biosynthesis genes acvA and ipnA, and of the aat promoter. Here, partial purification of PENR1 and western blotting using anti-HAPC sera indicated that the previously identified HAPC protein, which was suggested to be part of the CCAAT-binding complex AnCF, is also part of PENR1. This was confirmed by band shift assays using protein extracts of a delta hapC strain which exhibited no PENR1 DNA-binding activity. Supershift assays and immunoprecipitation analysis using anti-HAPC sera provided evidence that HAPC is part of the PENR1 complex. In delta hapC strains, penicillin production was reduced, as was expression of both an ipnA-lacZ and aat-lacZ gene fusion. Hence, HAPC-containing PENR1 appears to act as an activator on ipnA and aat expression. However, deletion of hapC had little effect on acvA expression during a fermentation run in fermentation medium. Previous results which had shown that specific deletion of the PENR1-binding site between acvA and ipnA resulted in a strong increase of expression of an acvA-uidA gene fusion, together with the present data, suggest the possibility of the existence of a repressor protein that binds close to or overlaps the PENR1-binding site. It is also shown that binding of PENR1 induced bending of a DNA fragment spanning the PENR1-binding site between acvA and ipnA in vitro.

  15. Improved penicillin amidase production using a genetically engineered mutant of escherichia coli ATCC 11105

    SciTech Connect

    Robas, N.; Zouheiry, H.; Branlant, G.; Branlant, C. )

    1993-01-05

    Penicillin G amidase (PGA) is a key enzyme for the industrial production of penicillin G derivatives used in therapeutics. Escherichia coli ATCC 11105 is the more commonly used strain for PGA production. To improve enzyme yield, the authors constructed various recombinant E. coli HB 101 and ATCC 11105 strains. For each strain, PGA production was determined for various concentrations of glucose and phenylacetic acid (PAA) in the medium. The E. coli strain, G271, was identified as the best performer (800 U NIPAB/L). This strain was obtained as follows: an E. coli ATCC 11105 mutant (E. coli G133) was first selected based on a low negative effect of glucose on PGA production. This mutant was then transformed with a pBR322 derivative containing the PGA gene. Various experiments were made to try to understand the reason for the high productivity of E. coli G271. The host strain, E. coli G133, was found to be mutated in one (or more) gene(s) whose product(s) act(s) in trans on the PGA gene expression. Its growth is not inhibited by high glucose concentration in the medium. Interestingly, whereas glucose still exerts some negative effect on the PGA production by E. coli G133, PGA production by its transformant (E. coli G271) is stimulated by glucose. The reason for this stimulation is discussed. Transformation of E. coli G133 with a pBR322 derivative containing the HindIII fragment of the PGA gene, showed that the performance of E. coli G271 depends both upon the host strain properties and the plasmid structure. Study of the production by the less efficient E. coli HB101 derivatives brought some light on the mechanism of regulation of the PGA gene.

  16. Genetic basis of penicillin resistance of S. aureus isolated in bovine mastitis

    PubMed Central

    2012-01-01

    Background The blaZ gene encoding penicillin resistance can be located either chromosomally or on plasmids. The aim of this study was to investigate the genetic relationships and to determine the location of the blaZ gene in S. aureus isolated in bovine mastitis in Finland and Sweden. Methods Seventy-eight β-lactamase positive S. aureus isolates from bovine mastitis (34 from Finland and 44 from Sweden) were included in the study. The localization of blaZ gene was determined by Southern blotting. The blaZ genes of the isolates were sequenced and the sequences were translated to beta-lactamase proteins and further grouped as different protein signatures. The isolates and, as control, 33 Swedish and 36 Finnish beta-lactamase negative isolates were typed with pulsed-field gel electrophoresis (PFGE). Results In 26 out of 34 Finnish isolates (76.5%) and in 25 out of 44 Swedish isolates (56.8%) the blaZ gene was localized on a plasmid. Six different protein signatures were found. One signature was found only in four Swedish isolates, but all other signatures were found both in Finnish and Swedish isolates. The PFGE results revealed a diversity of S. aureus clones. The protein signatures were not clearly associated with certain pulsotypes. Conclusions The plasmid location of the blaZ gene was not statistically significantly more common in Finland than in Sweden, and hence does not explain the higher proportion of penicillin-resistant isolates of S. aureus causing bovine mastitis in Finland compared to Sweden. PMID:23176642

  17. Excess Weapons Plutonium Immobilization in Russia

    SciTech Connect

    Jardine, L.; Borisov, G.B.

    2000-04-15

    The joint goal of the Russian work is to establish a full-scale plutonium immobilization facility at a Russian industrial site by 2005. To achieve this requires that the necessary engineering and technical basis be developed in these Russian projects and the needed Russian approvals be obtained to conduct industrial-scale immobilization of plutonium-containing materials at a Russian industrial site by the 2005 date. This meeting and future work will provide the basis for joint decisions. Supporting R&D projects are being carried out at Russian Institutes that directly support the technical needs of Russian industrial sites to immobilize plutonium-containing materials. Special R&D on plutonium materials is also being carried out to support excess weapons disposition in Russia and the US, including nonproliferation studies of plutonium recovery from immobilization forms and accelerated radiation damage studies of the US-specified plutonium ceramic for immobilizing plutonium. This intriguing and extraordinary cooperation on certain aspects of the weapons plutonium problem is now progressing well and much work with plutonium has been completed in the past two years. Because much excellent and unique scientific and engineering technical work has now been completed in Russia in many aspects of plutonium immobilization, this meeting in St. Petersburg was both timely and necessary to summarize, review, and discuss these efforts among those who performed the actual work. The results of this meeting will help the US and Russia jointly define the future direction of the Russian plutonium immobilization program, and make it an even stronger and more integrated Russian program. The two objectives for the meeting were to: (1) Bring together the Russian organizations, experts, and managers performing the work into one place for four days to review and discuss their work with each other; and (2) Publish a meeting summary and a proceedings to compile reports of all the excellent

  18. Immobilization of thermolysin to polyamide nonwoven materials.

    PubMed

    Moeschel, Klaus; Nouaimi, Meryem; Steinbrenner, Christa; Bisswanger, Hans

    2003-04-20

    In the last few years, an increasing number of biotechnological techniques have been applied to the restoration and conservation of works of art, paintings, old maps, and papers or books. Enzymes can solve problems that give restorers difficulties, although for many applications it is not possible to use soluble enzymes; therefore, it is necessary to look for suitable carriers for immobilization. Different methods for covalent immobilization of enzymes to polyamide nonwovens were tested, using thermolysin as an example. Two distinct strategies were pursued: (1). controlled, partial hydrolysis of the polymer and subsequent binding of the enzyme to the released amino and carboxy groups; and (2). attachment of reactive groups directly to the polyamide without disintegrating the polymeric structure (O-alkylation). Different spacers were used for covalent fixation of the enzyme in both cases. The enzyme was fixed to the released amino groups by glutaraldehyde, either with or without a spacer. Either way, active enzyme could be immobilized to the matrix. However, intense treatment caused severe damage to the stability of the nonwoven fabric, and reduced the mechanical strength. Conditions were investigated to conserve the nonwoven fabric structure while obtaining near-maximum immobilized enzyme activity. Immobilization of the enzyme to the released carboxy group after acid hydrolysis was performed using dicyclohexylcarbodiimide. In comparison to the enzyme bound via the amino group, the yield of immobilized enzyme activity was slightly lower when benzidine was taken as spacer and still lower with a 1,6-hexanediamine spacer. O-alkylation performed with dimethylsulfate caused severe damage to the nonwoven fabric structure. Considerably better results were obtained with triethyloxonium tetrafluoroborate. As the spacers 1,6-hexanediamine and adipic acid dihydrazide were used, activation for immobilizing thermolysin was performed with glutaraldehyde, adipimidate, and azide

  19. Estimating Benzathine Penicillin Need for the Treatment of Pregnant Women Diagnosed with Syphilis during Antenatal Care in High-Morbidity Countries

    PubMed Central

    Taylor, Melanie M.; Nurse-Findlay, Stephen; Zhang, Xiulei; Hedman, Lisa; Kamb, Mary L.; Broutet, Nathalie; Kiarie, James

    2016-01-01

    Background Congenital syphilis continues to be a preventable cause of global stillbirth and neonatal morbidity and mortality. Shortages of injectable penicillin, the only recommended treatment for pregnant women and infants with syphilis, have been reported by high-morbidity countries. We sought to estimate current and projected annual needs for benzathine penicillin in antenatal care settings for 30 high morbidity countries that account for approximately 33% of the global burden of congenital syphilis. Methods Proportions of antenatal care attendance, syphilis screening coverage in pregnancy, syphilis prevalence among pregnant women, and adverse pregnancy outcomes due to untreated maternal syphilis reported to WHO were applied to 2012 birth estimates for 30 high syphilis burden countries to estimate current and projected benzathine penicillin need for prevention of congenital syphilis. Results Using current antenatal care syphilis screening coverage and seroprevalence, we estimated the total number of women requiring treatment with at least one injection of 2.4 MU of benzathine penicillin in these 30 countries to be 351,016. Syphilis screening coverage at or above 95% for all 30 countries would increase the number of women requiring treatment with benzathine penicillin to 712,030. Based on WHO management guidelines, 351,016 doses of weight-based benzathine penicillin would also be needed for the live-born infants of mothers who test positive and are treated for syphilis in pregnancy. Assuming availability of penicillin and provision of treatment for all mothers diagnosed with syphilis, an estimated 95,938 adverse birth outcomes overall would be prevented including 37,822 stillbirths, 15,814 neonatal deaths, and 34,088 other congenital syphilis cases. Conclusion Penicillin need for maternal and infant syphilis treatment is high among this group of syphilis burdened countries. Initiatives to ensure a stable and adequate supply of benzathine penicillin for treatment

  20. Disposition of surplus fissile materials via immobilization

    SciTech Connect

    Gray, L.W.; Kan, T.; Sutcliffe, W.G.; McKibben, J.M.; Danker, W.

    1995-07-23

    In the Cold War aftermath, the US and Russia have agreed to large reductions in nuclear weapons. To aid in the selection of long-term management options, the USDOE has undertaken a multifaceted study to select options for storage and disposition of surplus plutonium (Pu). One disposition alternative being considered is immobilization. Immobilization is a process in which surplus Pu would be embedded in a suitable material to produce an appropriate form for ultimate disposal. To arrive at an appropriate form, we first reviewed published information on HLW immobilization technologies to identify forms to be prescreened. Surviving forms were screened using multi-attribute utility analysis to determine promising technologies for Pu immobilization. We further evaluated the most promising immobilization families to identify and seek solutions for chemical, chemical engineering, environmental, safety, and health problems; these problems remain to be solved before we can make technical decisions about the viability of using the forms for long-term disposition of Pu. All data, analyses, and reports are being provided to the DOE Office of Fissile Materials Disposition to support the Record of Decision that is anticipated in Summer of 1996.

  1. EFFECTS OF JOINT IMMOBILIZATION ON STANDING BALANCE

    PubMed Central

    de Freitas, Paulo B.; Freitas, Sandra M. S. F.; Duarte, Marcos; Latash, Mark L.; Zatsiorsky, Vladimir M.

    2009-01-01

    We investigated the effect of joint immobilization on the postural sway during quiet standing. We hypothesized that center of pressure (COP), rambling, and trembling trajectories could be affected by joint immobilization. Ten young adults stood on a force plate during 60 s without and with immobilized joints (only knees constrained, CK; knees and hips, CH; and knees, hips and trunk, CT), with their eyes opened (EO) or closed (EC). The root mean square deviation (RMS, the standard deviation from the mean) and mean speed of COP, rambling, and trembling trajectories in the anterior-posterior and medial-lateral directions were analyzed. Similar effects of vision were observed for both directions: larger amplitude for all variables was observed in the EC condition. In the anterior-posterior direction, postural sway increased only when the knees, hips and trunk were immobilized. For the medial-lateral direction, the RMS and the mean speed of the COP, rambling, and trembling displacements decreased after immobilization of knees and hips and knees, hips and trunk. These findings indicate that the inverted pendulum model is unable to completely explain the processes involved in the control of the quiet upright stance in the anterior-posterior and medial-lateral directions. PMID:19342114

  2. Accumulation of uranium by immobilized persimmon tannin

    SciTech Connect

    Sakaguchi, Takashi; Nakajima, Akira )

    1994-01-01

    We have discovered that the extracted juice of unripe astringent persimmon fruit, designated as kakishibu or shibuol, has an extremely high affinity for uranium. To develop efficient adsorbents for uranium, we tried to immobilize kakishibu (persimmon tannin) with various aldehydes and mineral acids. Persimmon tannin immobilized with glutaraldehyde can accumulate 1.71 g (14 mEq U) of uranium per gram of the adsorbent. The uranium accumulating capacity of this adsorbent is several times greater than that of commercially available chelating resins (2-3 mEq/g). Immobilized persimmon tannin has the most favorable features for uranium recovery; high selective adsorption ability, rapid adsorption rate, and applicability in both column and batch systems. The uranium retained on immobilized persimmon tannin can be quantitatively and easily eluted with a very dilute acid, and the adsorbent can thus be easily recycled in the adsorption-desorption process. Immobilized persimmon tannin also has a high affinity for thorium. 23 refs., 13 figs., 7 tabs.

  3. Improved nonporous magnetic supports for immobilized enzymes.

    PubMed

    Halling, P J; Dunnill, P

    1979-03-01

    Ni powders coated by deposition of TiO2 or controlled oxidation to NiO develop substantial resistance to corrosion. Chymotrypsin immobilized to these coated Ni supports shows very high stability of activity on storage. Chymotrypsin immobilized by adsorption and glutaraldehyde crosslinking was fairly rapidly eluted under operational conditions in the presence of substrate. If 3-aminopropyltriethoxysilane (APS) was used to produce a covalent linkage, desorption of enzyme still occurred because of relatively unstable bonding of the silane to the oxide surface. A more stable attachment was produced by joining together many silane links with a layer of polyglutaraldehyde. The mechanism of action of APS as a coupling agent under these conditions is discussed. gamma-Fe2O3, and particularly a Mn-Zn ferrite, are suitable magnetic support materials available with smaller particle sizes. Particles below 1 mum give the expected higher specific activities of immobilized enzymes.

  4. Immobilization of lipase from grey mullet.

    PubMed

    Aryee, Alberta N A; Simpson, Benjamin K

    2012-12-01

    Grey mullet (Mugil cephalus) lipase was isolated using para-aminobenzamidine agarose and immobilized on octyl Sepharose CL-4B (o-Sep). Immobilized grey mullet lipase (GMLi) had a 10 °C higher optimum temperature compared to the free enzyme and showed remarkable thermal stability. GMLi was most active within the pH range of 8.0-9.5 with an optimum at 8.5. Immobilization also enhanced the storage stability and reusability of the enzyme with minimal changes in efficiency during repeated batches. GMLi showed variable stabilities in various organic solvents. A signal in the amide I absorption region of the FTIR spectrum of GMLi was attributed to the protein layer on o-Sep. The surface morphology of o-Sep was visualized on a Zeiss stereomicroscope as globular-shaped beads.

  5. Immobilization of the Methanogenic bacterium methanosarcina barkeri

    SciTech Connect

    Scherer, P.; Kluge, M.; Klein, J.; Sahm, H.

    1981-05-01

    Whole cells of the methanogen Methanosarcina barkeri were immobilized in an alginate network which was crosslinked with Ca/sup 2+/ calcium ions. The rates of methanol conversion to methane of entrapped cells were found to be in the same range as the corresponding rates of free cells. Furthermore, immobilized cells were active for a longer period than free cells. The particle size of the spherical alginate beads and thus diffusion has no obvious influence on the turnover of methanol. The half-value period for methanol conversion activity determined in a buffer medium was approximately 4 days at 37/degree/C for entrapped cells. The high rates of methanol degradation indicated that the immobilization technique preserved the cellular functions of this methanogenic bacterium. 24 refs.

  6. An overview of technologies for immobilization of enzymes and surface analysis techniques for immobilized enzymes

    PubMed Central

    Mohamad, Nur Royhaila; Marzuki, Nur Haziqah Che; Buang, Nor Aziah; Huyop, Fahrul; Wahab, Roswanira Abdul

    2015-01-01

    The current demands of sustainable green methodologies have increased the use of enzymatic technology in industrial processes. Employment of enzyme as biocatalysts offers the benefits of mild reaction conditions, biodegradability and catalytic efficiency. The harsh conditions of industrial processes, however, increase propensity of enzyme destabilization, shortening their industrial lifespan. Consequently, the technology of enzyme immobilization provides an effective means to circumvent these concerns by enhancing enzyme catalytic properties and also simplify downstream processing and improve operational stability. There are several techniques used to immobilize the enzymes onto supports which range from reversible physical adsorption and ionic linkages, to the irreversible stable covalent bonds. Such techniques produce immobilized enzymes of varying stability due to changes in the surface microenvironment and degree of multipoint attachment. Hence, it is mandatory to obtain information about the structure of the enzyme protein following interaction with the support surface as well as interactions of the enzymes with other proteins. Characterization technologies at the nanoscale level to study enzymes immobilized on surfaces are crucial to obtain valuable qualitative and quantitative information, including morphological visualization of the immobilized enzymes. These technologies are pertinent to assess efficacy of an immobilization technique and development of future enzyme immobilization strategies. PMID:26019635

  7. Cervical spine immobilization in the elderly population

    PubMed Central

    Phan, Kevin; Mobbs, Ralph J.; Wilson, David; Ball, Jonathon

    2016-01-01

    Background Immobilization of the cervical spine is a cornerstone of spinal injury management. In the context of suspected cervical spine injury, patients are immobilized in a ‘neutral position’ based on the head and trunk resting on a flat surface. It is hypothesized that the increased thoracic kyphosis and loss of cervical lordosis seen in elderly patients may require alternative cervical immobilization, compared with the ‘neutral position’. Methods To investigate this, an audit of pan-scan CT performed on consecutive major trauma patients aged over 65 years was carried out over a 6-month period. Utilizing the pan-CT’s localizing scout film, a novel measurement, the ‘chin-brow horizontal’ angle was independently measured by a senior spine surgeon (RJM) and a neurosurgeon (PJR) with the gantry used as a horizontal zero- degree reference. The benefit of the ‘chin-brow horizontal’ angle in the trauma setting is it can be assessed from the bedside whilst the patient is immobilized against a flat surface. Results During the 6-month study period, 58 patients were identified (30 male, 28 female), with an average age of 77.6 years (minimum 65, maximum 97). Results showed that ‘chin-brow horizontal’ angles varied widely, between +15.8 degrees in flexion to −30.5 degrees in extension (mean −12.4 degrees in extension, standard deviation 9.31 degrees. The interobserver correlation was 0.997 (95% CI: 0.995–0.998). Conclusions These findings suggest that, due to degenerative changes commonly seen in elderly patients, the routine use of the ‘neutral position’ adopted for cervical spine immobilization may not be appropriate in this population. We suggest that consideration be taken in cervical spine immobilization, with patients assessed on an individual basis including the fracture morphology, to minimize the risk of fracture displacement and worsened neurological deficit.

  8. Plutonium Immobilization Can Loading Conceptual Design

    SciTech Connect

    Kriikku, E.

    1999-05-13

    'The Plutonium Immobilization Facility will encapsulate plutonium in ceramic pucks and seal the pucks inside welded cans. Remote equipment will place these cans in magazines and the magazines in a Defense Waste Processing Facility (DWPF) canister. The DWPF will fill the canister with glass for permanent storage. This report discusses the Plutonium Immobilization can loading conceptual design and includes a process block diagram, process description, preliminary equipment specifications, and several can loading issues. This report identifies loading pucks into cans and backfilling cans with helium as the top priority can loading development areas.'

  9. Involvement of the Eukaryote-Like Kinase-Phosphatase System and a Protein That Interacts with Penicillin-Binding Protein 5 in Emergence of Cephalosporin Resistance in Cephalosporin-Sensitive Class A Penicillin-Binding Protein Mutants in Enterococcus faecium

    PubMed Central

    Desbonnet, Charlene; Tait-Kamradt, Amelia; Garcia-Solache, Monica; Dunman, Paul; Coleman, Jeffrey; Arthur, Michel

    2016-01-01

    ABSTRACT The intrinsic resistance of Enterococcus faecium to ceftriaxone and cefepime (here referred to as “cephalosporins”) is reliant on the presence of class A penicillin-binding proteins (Pbps) PbpF and PonA. Mutants lacking these Pbps exhibit cephalosporin susceptibility that is reversible by exposure to penicillin and by selection on cephalosporin-containing medium. We selected two cephalosporin-resistant mutants (Cro1 and Cro2) of class A Pbp-deficient E. faecium CV598. Genome analysis revealed changes in the serine-threonine kinase Stk in Cro1 and a truncation in the associated phosphatase StpA in Cro2 whose respective involvements in resistance were confirmed in separate complementation experiments. In an additional effort to identify proteins linked to cephalosporin resistance, we performed tandem affinity purification using Pbp5 as bait in penicillin-exposed E. faecium; these experiments yielded a protein designated Pbp5-associated protein (P5AP). Transcription of the P5AP gene was increased after exposure to penicillin in wild-type strains and in Cro2 and suppressed in Cro2 complemented with the wild-type stpA. Transformation of class A Pbp-deficient strains with the plasmid-carried P5AP gene conferred cephalosporin resistance. These data suggest that Pbp5-associated cephalosporin resistance in E. faecium devoid of typical class A Pbps is related to the presence of P5AP, whose expression is influenced by the activity of the serine-threonine phosphatase/kinase system. PMID:27048803

  10. Quantitative determination method for trace amount of penicillin contaminants in commercially available drug product by HPLC coupled with tandem mass spectrometry.

    PubMed

    Takada, Wataru; Adachi, Toshikazu; Kihara, Noriaki; Kitamura, Satoshi; Kitagawa, Teruyuki; Mifune, Masaki; Saito, Yutaka

    2005-02-01

    A quantitative determination method for trace amount of penicillin contaminants in an active pharmaceutical ingredient (API) has been developed. Selective extraction of penicillin contaminants from the matrix containing API and specific separation among penicillin contaminants were achieved through an on-line column switching technique with gradient elution, followed by tandem mass spectrometric determination. Validation was conducted on the developed method in terms of specificity, linearity, accuracy, precision, and detection limit, and appeared reasonable. The detection limit was estimated as 0.03 ng/ml or lower of the concentration of penicillin contaminants in the preparation, corresponding to 4 parts par billion (ppb) against the API. This fulfilled the regulatory requirement by the authorities.

  11. Alterations in penicillin binding protein gene of Streptococcus pneumoniae and their correlation with susceptibility patterns.

    PubMed

    Ohsaki, Yoshinobu; Tachibana, Mineji; Nakanishi, Kyoko; Nakao, Shoko; Saito, Kumiko; Toyoshima, Eri; Sato, Maki; Takahashi, Toru; Osanai, Shinobu; Itoh, Yoshihisa; Kikuchi, Kenjiro

    2003-08-01

    Penicillin binding protein (pbp) gene alterations of 328 clinical isolates of Streptococcus pneumoniae were examined for a correlation with their antibiotic-resistance. The frequency of penicillin G (PEN-G) resistance was determined to clarify susceptibility to several antibiotics, namely PEN-G, ampicillin, sulbactam/ampicillin, cefozopram, panipenem (PAPM), clarithromycin (CLR), azithromycin (AZM) and levofloxacin (LVX). Oligonucleotide primers for three pbp genes (pbp1a, pbp2x and pbp2b) were used to detect mutations in pbp. Of the strains, 25.9% were classified as Pen-Gs, 68.0% as Pen-Gir and 6.1% as Pen-Gr. The polymerase chain reaction product for wild-type pbp1a was found in 185 isolates, that for wild-type pbp2x was found in 66 isolates and that for wild-type pbp2b was found in 213 isolates. None of these three genes was detectable in 100 isolates while all of them were detected in 64 isolates (1aw/2xw/2bw). Of those 64 isolates with 1aw/2xw/2bw, the minimum inhibitory concentration (MIC) of PEN-G was < or =0.06 mg/l for 54 isolates and 0.12 mg/l for 10 isolates. Of the 272 strains for which the MIC of PAPM was < or =0.03 mg/l, there were 85 Pen-Gs, 184 Pen-Gir and three Pen-Gr isolates. Three strains for which the MIC of LVX was > or =4.0 mg/l included one Pen-Gs and two Pen-Gir isolates. The MICs of CLR correlated significantly with those of AZM. The MIC of CLR was > or =1 mg/l for 216 isolates, and the MIC of AZM was > or =1 mg/l for 244 of them. These data suggested that PAPM may be effective against S. pneumoniae infection, although acquisition of resistance should be considered. LVX also seemed to be effective against S. pneumoniae.

  12. A Proposal for Six Sigma Integration for Large-Scale Production of Penicillin G and Subsequent Conversion to 6-APA

    PubMed Central

    Nandi, Anirban; Danquah, Michael K.

    2014-01-01

    Six Sigma methodology has been successfully applied to daily operations by several leading global private firms including GE and Motorola, to leverage their net profits. Comparatively, limited studies have been conducted to find out whether this highly successful methodology can be applied to research and development (R&D). In the current study, we have reviewed and proposed a process for a probable integration of Six Sigma methodology to large-scale production of Penicillin G and its subsequent conversion to 6-aminopenicillanic acid (6-APA). It is anticipated that the important aspects of quality control and quality assurance will highly benefit from the integration of Six Sigma methodology in mass production of Penicillin G and/or its conversion to 6-APA. PMID:25057428

  13. Molecular cloning of Bacillus sphaericus penicillin V amidase gene and its expression in Escherichia coli and Bacillus subtilis.

    PubMed Central

    Olsson, A; Hagström, T; Nilsson, B; Uhlén, M; Gatenbeck, S

    1985-01-01

    The Bacillus sphaericus gene coding for penicillin V amidase, which catalyzes the hydrolysis of penicillin V to yield 6-aminopenicillanic acid and phenoxyacetic acid, has been isolated by molecular cloning in Escherichia coli. The gene is contained within a 2.2-kilobase HindIII-PstI fragment and is expressed when transferred into E. coli and Bacillus subtilis. The expression in B. subtilis carrying the recombinant plasmid is approximately two times higher than in the original B. sphaericus strain. A comparison of the purified enzyme from B. sphaericus and the expressed gene product in E. coli minicells suggests that the native enzyme consists of four identical subunits, each with a molecular weight of 35,000. Images PMID:3923928

  14. A Proposal for Six Sigma Integration for Large-Scale Production of Penicillin G and Subsequent Conversion to 6-APA.

    PubMed

    Nandi, Anirban; Pan, Sharadwata; Potumarthi, Ravichandra; Danquah, Michael K; Sarethy, Indira P

    2014-01-01

    Six Sigma methodology has been successfully applied to daily operations by several leading global private firms including GE and Motorola, to leverage their net profits. Comparatively, limited studies have been conducted to find out whether this highly successful methodology can be applied to research and development (R&D). In the current study, we have reviewed and proposed a process for a probable integration of Six Sigma methodology to large-scale production of Penicillin G and its subsequent conversion to 6-aminopenicillanic acid (6-APA). It is anticipated that the important aspects of quality control and quality assurance will highly benefit from the integration of Six Sigma methodology in mass production of Penicillin G and/or its conversion to 6-APA.

  15. Maturity and security assessment of pilot-scale aerobic co-composting of penicillin fermentation dregs (PFDs) with sewage sludge.

    PubMed

    Yang, Lian; Zhang, Shihua; Chen, Zhiqiang; Wen, Qinxue; Wang, Yao

    2016-03-01

    In this work, penicillin fermentation dregs (PFDs) and sewage sludge (SWS) were co-composted to analyze the possibility of recycling nutrients in PFDs. The temperature was maintained above 55°C for more than 3 days, and the final electrical conductivity (EC), pH and C/N all met the national standards in maturity. A nearly 100% removal of the residual penicillin was achieved, and the seed germination index (GI) increased from 0.02% to 83.54±3.1% by the end of the composting process. However, monitoring the quantity of antibiotic resistance genes (ARGs) showed that the logarithm of the number of copies of blaTEM increased from 4.17±0.19 at the initial phase to 8.92±0.27 by the end of the composting process, which means that there is a high risk for land use when using PFD compost products. PMID:26799590

  16. Synergistic effects of dicloxacillin or clavulanic acid in combination with penicillin G or cephalothin against Yersinia enterocolitica.

    PubMed Central

    Jimenez-Valera, M; Ruiz-Bravo, A; Ramos-Cormenzana, A

    1986-01-01

    Cultures of Yersinia enterocolitica grown at 22 degrees C produced beta-lactamases, whereas cultures grown at 37 degrees C produced these enzymes much less effectively. Both dicloxacillin and clavulanic acid inhibited the beta-lactamase activity of bacterial crude extracts and potentiated the activity of penicillin G or cephalothin against 14 Y. enterocolitica strains. It appeared that the beta-lactamase activity present in Y. enterocolitica cells grown at 37 degrees C was great enough to play a role in bacterial resistance to beta-lactam antibiotics, since combining penicillin G or cephalothin with clavulanic acid or dicloxacillin resulted in synergistic activity against cultures grown at 37 degrees C that was equal to or greater than the activity against cultures grown at 22 degrees C. PMID:3488014

  17. Enhanced enzyme stability through site-directed covalent immobilization.

    PubMed

    Wu, Jeffrey Chun Yu; Hutchings, Christopher Hayden; Lindsay, Mark Jeffrey; Werner, Christopher James; Bundy, Bradley Charles

    2015-01-10

    Breakthroughs in enzyme immobilization have enabled increased enzyme recovery and reusability, leading to significant decreases in the cost of enzyme use and fueling biocatalysis growth. However, current enzyme immobilization techniques suffer from leaching, enzyme stability, and recoverability and reusability issues. Moreover, these techniques lack the ability to control the orientation of the immobilized enzymes. To determine the impact of orientation on covalently immobilized enzyme activity and stability, we apply our PRECISE (Protein Residue-Explicit Covalent Immobilization for Stability Enhancement) system to a model enzyme, T4 lysozyme. The PRECISE system uses non-canonical amino acid incorporation and the Huisgen 1,3-dipolar cycloaddition "click" reaction to enable directed enzyme immobilization at rationally chosen residues throughout an enzyme. Unlike previous site-specific systems, the PRECISE system is a truly covalent immobilization method. Utilizing this system, enzymes immobilized at proximate and distant locations from the active site were tested for activity and stability under denaturing conditions. Our results demonstrate that orientation control of covalently immobilized enzymes can provide activity and stability benefits exceeding that of traditional random covalent immobilization techniques. PRECISE immobilized enzymes were 50 and 73% more active than randomly immobilized enzymes after harsh freeze-thaw and chemical denaturant treatments.

  18. Invertase in immobilized cells of Papaver somniferum L.

    PubMed

    Stano, J; Nemec, P; Bezáková, L; Kovács, P; Kákoniova, D; Neubert, K; Lisková, D

    1997-03-01

    Papaver somniferum L., (opium poppy) cells were after permeabilization in Tween 80 immobilized by glutaraldehyde without any carrier. Cells immobilized by cross-linking performed the hydrolysis of sucrose. The immobilized cells were characterized by high invertase activity and appropriate physico-mechanical properties.

  19. Short-Term Limb Immobilization Affects Cognitive Motor Processes

    ERIC Educational Resources Information Center

    Toussaint, Lucette; Meugnot, Aurore

    2013-01-01

    We examined the effects of a brief period of limb immobilization on the cognitive level of action control. A splint placed on the participants' left hand was used as a means of immobilization. We used a hand mental rotation task to investigate the immobilization-induced effects on motor imagery performance (Experiments 1 and 2) and a number mental…

  20. Immobilization routes - they're not standing still

    SciTech Connect

    Basta, N.

    1982-04-19

    This paper reviews recent developments in the applications of enzyme immobilization techniques in various industries. Following success in high-fructose corn syrup production, enzyme immobilization is now making inroads in food processing and biomass-energy conversion. New studies focus on the immobilization of whole cells.