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Sample records for glycopeptide antibiotic production

  1. Opportunities for synthetic biology in antibiotics: expanding glycopeptide chemical diversity.

    PubMed

    Thaker, Maulik N; Wright, Gerard D

    2015-03-20

    Synthetic biology offers a new path for the exploitation and improvement of natural products to address the growing crisis in antibiotic resistance. All antibiotics in clinical use are facing eventual obsolesce as a result of the evolution and dissemination of resistance mechanisms, yet there are few new drug leads forthcoming from the pharmaceutical sector. Natural products of microbial origin have proven over the past 70 years to be the wellspring of antimicrobial drugs. Harnessing synthetic biology thinking and strategies can provide new molecules and expand chemical diversity of known antibiotic scaffolds to provide much needed new drug leads. The glycopeptide antibiotics offer paradigmatic scaffolds suitable for such an approach. We review these strategies here using the glycopeptides as an example and demonstrate how synthetic biology can expand antibiotic chemical diversity to help address the growing resistance crisis. PMID:23654249

  2. Facile Synthetic Access to Glycopeptide Antibiotic Precursor Peptides for the Investigation of Cytochrome P450 Action in Glycopeptide Antibiotic Biosynthesis.

    PubMed

    Brieke, Clara; Kratzig, Veronika; Peschke, Madeleine; Cryle, Max J

    2016-01-01

    The glycopeptide antibiotics are an important class of complex, medically relevant peptide natural products. Given that the production of such compounds all stems from in vivo biosynthesis, understanding the mechanisms of the natural assembly system--consisting of a nonribosomal-peptide synthetase machinery (NRPS) and further modifying enzymes--is vital. In order to address the later steps of peptide biosynthesis, which are catalyzed by Cytochrome P450s that interact with the peptide-producing nonribosomal peptide synthetase, peptide substrates are required: these peptides must also be in a form that can be conjugated to carrier protein domains of the nonribosomal peptide synthetase machinery. Here, we describe a practical and effective route for the solid phase synthesis of glycopeptide antibiotic precursor peptides as their Coenzyme A (CoA) conjugates to allow enzymatic conjugation to carrier protein domains. This route utilizes Fmoc-chemistry suppressing epimerization of racemization-prone aryl glycine derivatives and affords high yields and excellent purities, requiring only a single step of simple solid phase extraction for chromatographic purification. With this, comprehensive investigations of interactions between various NRPS-bound substrates and Cytochrome P450s are enabled. PMID:26831703

  3. Optical biosensors. Monitoring studies of glycopeptide antibiotic fermentation using white light interference.

    PubMed

    Tünnemann, R; Mehlmann, M; Süssmuth, R D; Bühler, B; Pelzer, S; Wohlleben, W; Fiedler, H P; Wiesmüller, K H; Gauglitz, G; Jung, G

    2001-09-01

    This paper describes the design, characterization, and use of an optical biosensor suited for the process control of biotechnological processes. The detector principle is based on reflectometric interference spectroscopy (RIfS). RIfS enables a label-free, product-specific monitoring, with a future outline for on-line process control. The potential of the RIfS biosensor is exemplified by the qualitative and quantitative monitoring of the microbial production of vancomycin-type glycopeptide antibiotics. PMID:11569825

  4. The effect of fosfomycin on glycopeptide antibiotic-induced nephrotoxicity in rats.

    PubMed

    Yoshiyama, Y; Yazaki, T; Wong, P C; Beauchamp, D; Kanke, M

    2001-12-01

    The effect of coadministration of fosfomycin (FOM) on glycopeptide antibiotic-induced nephrotoxicity for 3 days was investigated in rats. To induce nephrotoxicity in a short time, gentamicin (GM) was also coadministered. In the present study, FOM decreased glycopeptide antibiotic-induced nephrotoxicity as shown by reduced urinary excretion of N-acetyl-beta-D-glucosaminidase (NAG) as well as fewer histopathological signs of nephrotoxicity in the groups treated with the combination of glycopeptide and FOM as compared with a glycopeptide alone. In addition, the higher the dose of FOM, the more it decreased urinary NAG levels, suggesting that the role of FOM in alleviating nephrotoxicity is dose dependent. The accumulation of teicoplanin and vancomycin was significantly lower in the renal cortex of rats treated with the combination of glycopeptide antibiotics and FOM as compared with glycopeptide antibiotics alone (P < 0.05). In conclusion, the concomitant administration of FOM and glycopeptide antibiotics may help to achieve a chemotherapeutic strategy that reduces the nephrotoxic effects of glycopeptide antibiotics. PMID:11810591

  5. MM 55266 and MM 55268, glycopeptide antibiotics produced by a new strain of Amycolatopsis. Isolation, purification and structure determination.

    PubMed

    Box, S J; Coates, N J; Davis, C J; Gilpin, M L; Houge-Frydrych, C S; Milner, P H

    1991-08-01

    Two novel glycopeptide antibiotics MM 55266 and MM 55268 containing fatty acid acyl functions, and of molecular formula C86H89N8O35Cl5 and C87H91N8O35Cl5, respectively, have been isolated and identified from a complex produced by Amycolatopsis sp. NCIB 40089. Fermentation conditions for their production, and methods for their isolation are described. Structures have been deduced by use of COSY and NOE NMR techniques and supported by chemical degradation studies. Both glycopeptides possessed good antibacterial activity against Gram-positive organisms. PMID:1917694

  6. Relationship between Glycopeptide Production and Resistance in the Actinomycete Nonomuraea sp. ATCC 39727

    PubMed Central

    Binda, Elisa; Carrano, Lucia; Bibb, Mervyn; Marinelli, Flavia

    2014-01-01

    Glycopeptides and β-lactams inhibit bacterial peptidoglycan synthesis in Gram-positive bacteria; resistance to these antibiotics is studied intensively in enterococci and staphylococci because of their relevance to infectious disease. Much less is known about antibiotic resistance in glycopeptide-producing actinomycetes that are likely to represent the evolutionary source of resistance determinants found in bacterial pathogens. Nonomuraea sp. ATCC 39727, the producer of A40926 (the precursor for the semisynthetic dalbavancin), does not harbor the canonical vanHAX genes. Consequently, we investigated the role of the β-lactam-sensitive d,d-peptidase/d,d-carboxypeptidase encoded by vanYn, the only van-like gene found in the A40926 biosynthetic gene cluster, in conferring immunity to the antibiotic in Nonomuraea sp. ATCC 39727. Taking advantage of the tools developed recently to genetically manipulate this uncommon actinomycete, we varied vanYn gene dosage and expressed vanHatAatXat from the teicoplanin producer Actinoplanes teichomyceticus in Nonomuraea sp. ATCC 39727. Knocking out vanYn, complementing a vanYn mutant, or duplicating vanYn had no effect on growth but influenced antibiotic resistance and, in the cases of complementation and duplication, antibiotic production. Nonomuraea sp. ATCC 39727 was found to be resistant to penicillins, but its glycopeptide resistance was diminished in the presence of penicillin G, which inhibits VanYn activity. The heterologous expression of vanHatAatXat increased A40926 resistance in Nonomuraea sp. ATCC 39727 but did not increase antibiotic production, indicating that the level of antibiotic production is not directly determined by the level of resistance. The vanYn-based self-resistance in Nonomuraea sp. ATCC 39727 resembles the glycopeptide resistance mechanism described recently in mutants of Enterococcus faecium selected in vitro for high-level resistance to glycopeptides and penicillins. PMID:24957828

  7. Crystal Structure of StaL, A Glycopeptide Antibiotic Sulfotransferase from Streptomyces Toyocaensis

    SciTech Connect

    Shi,R.; Lamb, S.; Bhat, S.; Sulea, T.; Wright, G.; Matte, A.; Cygler, M.

    2007-01-01

    Over the past decade, antimicrobial resistance has emerged as a major public health crisis. Glycopeptide antibiotics such as vanco-mycin and teicoplanin are clinically important for the treatment of Gram-positive bacterial infections. StaL is a 3'-phosphoadenosine 5'-phosphosulfate-dependent sulfotransferase capable of sulfating the cross-linked heptapeptide substrate both in vivo and in vitro, yielding the product A47934 [GenBank], unique teicoplanin-class glycopeptide antibiotic. The sulfonation reaction catalyzed by StaL constitutes the final step in A47934 [GenBank] biosynthesis. Here we report the crystal structure of StaL and its complex with the cofactor product 3'-phosphoadenosine 5'-phosphate. This is only the second prokaryotic sulfotransferase to be structurally characterized. StaL belongs to the large sulfotransferase family and shows higher similarity to cytosolic sulfotransferases (ST) than to the bacterial ST (Stf0). StaL has a novel dimerization motif, different from any other STs that have been structurally characterized. We have also applied molecular modeling to investigate the binding mode of the unique substrate, desulfo-A47934. Based on the structural analysis and modeling results, a series of residues was mutated and kinetically characterized. In addition to the conserved residues (Lys{sup 12}, His{sup 67}, and Ser{sup 98}), molecular modeling, fluorescence quenching experiments, and mutagenesis studies identified several other residues essential for substrate binding and/or activity, including Trp{sup 34}, His{sup 43}, Phe{sup 77}, Trp{sup 132}, and Glu{sup 205}.

  8. Cold Stress Makes Escherichia coli Susceptible to Glycopeptide Antibiotics by Altering Outer Membrane Integrity.

    PubMed

    Stokes, Jonathan M; French, Shawn; Ovchinnikova, Olga G; Bouwman, Catrien; Whitfield, Chris; Brown, Eric D

    2016-02-18

    A poor understanding of the mechanisms by which antibiotics traverse the outer membrane remains a considerable obstacle to the development of novel Gram-negative antibiotics. Herein, we demonstrate that the Gram-negative bacterium Escherichia coli becomes susceptible to the narrow-spectrum antibiotic vancomycin during growth at low temperatures. Heterologous expression of an Enterococcus vanHBX vancomycin resistance cluster in E. coli confirmed that the mechanism of action was through inhibition of peptidoglycan biosynthesis. To understand the nature of vancomycin permeability, we screened for strains of E. coli that displayed resistance to vancomycin at low temperature. Surprisingly, we observed that mutations in outer membrane biosynthesis suppressed vancomycin activity. Subsequent chemical analysis of lipopolysaccharide from vancomycin-sensitive and -resistant strains confirmed that suppression was correlated with truncations in the core oligosaccharide of lipopolysaccharide. These unexpected observations challenge the current understanding of outer membrane permeability, and provide new chemical insights into the susceptibility of E. coli to glycopeptide antibiotics. PMID:26853624

  9. Glycopeptide Antibiotic To Overcome the Intrinsic Resistance of Gram-Negative Bacteria.

    PubMed

    Yarlagadda, Venkateswarlu; Manjunath, Goutham B; Sarkar, Paramita; Akkapeddi, Padma; Paramanandham, Krishnamoorthy; Shome, Bibek R; Ravikumar, Raju; Haldar, Jayanta

    2016-02-12

    The emergence of drug resistance along with a declining pipeline of clinically useful antibiotics has made it vital to develop more effective antimicrobial therapeutics, particularly against difficult-to-treat Gram-negative pathogens (GNPs). Many antibacterial agents, including glycopeptide antibiotics such as vancomycin, are inherently inactive toward GNPs because of their inability to cross the outer membrane of these pathogens. Here, we demonstrate, for the first time, lipophilic cationic (permanent positive charge) vancomycin analogues were able to permeabilize the outer membrane of GNPs and overcome the inherent resistance of GNPs toward glycopeptides. Unlike vancomycin, these analogues were shown to have a high activity against a variety of multidrug-resistant clinical isolates such as Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii. In the murine model of carbapenem-resistant A. baumannii infection, the optimized compound showed potent activity with no observed toxicity. The notable activity of these compounds is attributed to the incorporation of new membrane disruption mechanisms (cytoplasmic membrane depolarization along with outer and inner (cytoplasmic) membrane permeabilization) into vancomycin. Therefore, our results indicate the potential of the present vancomycin analogues to be used against drug-resistant GNPs, thus strengthening the antibiotic arsenal for combating Gram-negative bacterial infections. PMID:27624964

  10. Peptidoglycan synthesis and structure in Staphylococcus haemolyticus expressing increasing levels of resistance to glycopeptide antibiotics.

    PubMed Central

    Billot-Klein, D; Gutmann, L; Bryant, D; Bell, D; Van Heijenoort, J; Grewal, J; Shlaes, D M

    1996-01-01

    The structures of cytoplasmic peptidoglycan precursor and mature peptidoglycan of an isogenic series of Staphylococcus haemolyticus strains expressing increasing levels of resistance to the glycopeptide antibiotics teicoplanin and vancomycin (MICs, 8 to 32 and 4 to 16 microg/ml, respectively) were determined. High-performance liquid chromatography, mass spectrometry, amino acid analysis, digestion by R39 D,D-carboxypeptidase, and N-terminal amino acid sequencing were utilized. UDP-muramyl-tetrapeptide-D-lactate constituted 1.7% of total cytoplasmic peptidoglycan precursors in the most resistant strain. It is not clear if this amount of depsipeptide precursor can account for the levels of resistance achieved by this strain. Detailed structural analysis of mature peptidoglycan, examined for the first time for this species, revealed that the peptidoglycan of these strains, like that of other staphylococci, is highly cross-linked and is composed of a lysine muropeptide acceptor containing a substitution at its epsilon-amino position of a glycine-containing cross bridge to the D-Ala 4 of the donor, with disaccharide-pentapeptide frequently serving as an acceptor for transpeptidation. The predominant cross bridges were found to be COOH-Gly-Gly-Ser-Gly-Gly-NH2 and COOH-Ala-Gly-Ser-Gly-Gly-NH2. Liquid chromatography-mass spectrometry analysis of the peptidoglycan of resistant strains revealed polymeric muropeptides bearing cross bridges containing an additional serine in place of glycine (probable structures, COOH-Gly-Ser-Ser-Gly-Gly-NH2 and COOH-Ala-Gly-Ser-Ser-Gly-NH2). Muropeptides bearing an additional serine in their cross bridges are estimated to account for 13.6% of peptidoglycan analyzed from resistant strains of S. haemolyticus. A soluble glycopeptide target (L-Ala-gamma-D-iso-glutamyl-L-Lys-D-Ala-D-Ala) was able to more effectively compete for vancomycin when assayed in the presence of resistant cells than when assayed in the presence of susceptible cells

  11. Effects of the new glycopeptide antibiotic teicoplanin on platelet function and blood coagulation.

    PubMed Central

    Agnelli, G; Longetti, M; Guerciolini, R; Menichetti, F; Grasselli, S; Boldrini, F; Bucaneve, G; Nenci, G G; Del Favero, A

    1987-01-01

    Teicoplanin, a new glycopeptide antibiotic, is structurally related to ristocetin, an antibiotic known to induce human platelet agglutination and, thus, thrombocytopenia and thromboembolic side effects. The aim of this study was to evaluate the effects of teicoplanin on platelet function in vitro and ex vivo and on blood coagulation ex vivo. In the in vitro studies, spontaneous platelet aggregation; platelet aggregation induced by ADP, collagen, and ristocetin; and the release of beta-thromboglobulin from platelets were assessed. Platelets from healthy subjects were incubated with teicoplanin at final concentrations of 100, 1,500, 5,000, and 10,000 micrograms/ml. The maximal achievable concentration with therapeutic doses is 100 micrograms/ml. When compared with saline, teicoplanin at concentrations of 100 and 1,500 micrograms/ml had no effect on platelet function, but at concentrations of 5,000 and 10,000 micrograms/ml, it induced greater spontaneous platelet aggregation (P less than 0.01) and inhibited platelet aggregation induced by ADP, collagen, and ristocetin (P less than 0.01). Teicoplanin at concentrations of 100, 1,500, and 5,000 micrograms/ml did not induce the release of beta-thromboglobulin, in contrast to teicoplanin at a concentration of 10,000 micrograms/ml and ristocetin at a concentration of 1.5 mg/ml (P less than 0.01). In the ex vivo studies, platelet count, bleeding time, plasma beta-thromboglobulin, platelet aggregation induced by ADP, ristocetin, and epinephrine, activated partial thromboplastin time, prothrombin time, thrombin clotting time, and serum fibrinogen degradation products were evaluated at days 0, 3, and 6 and at 72 h after the end of therapy. All subjects completed the study without evidence of side effects. When compared with the pretreatment values, none of the values from these assays showed a significant change at any time during and after treatment. We concluded that platelet function and blood coagulation are not affected by

  12. Structure and Function of the Glycopeptide N-methyltransferase MtfA, a Tool for the Biosynthesis of Modified Glycopeptide Antibiotics

    SciTech Connect

    Shi, Rong; Lamb, Sherry S.; Zakeri, Bijan; Proteau, Ariane; Cui, Qizhi; Sulea, Traian; Matte, Allan; Wright, Gerard D.; Cygler, Miroslaw

    2009-06-01

    There is a considerable interest in the modification of existing antibiotics to generate new antimicrobials. Glycopeptide antibiotics (GPAs) are effective against serious Gram-positive bacterial pathogens including methicillin-resistant Staphylococcus aureus. However, resistance to these antibiotics is becoming a serious problem requiring new strategies. We show that the Amycolatopsis orientalis (S)-adenosyl-L-methionine-dependent methyltransferase MtfA, from the vancomycin-class GPA chloroeremomycin biosynthetic pathway, catalyzes in vivo and in vitro methyl transfer to generate methylated GPA derivatives of the teicoplanin class. The crystal structure of MtfA complexed with (S)-adenosyl-L-methionine, (S)-adenosylhomocysteine, or sinefungin inhibitor, coupled with mutagenesis, identified His228 as a likely general base required for methyl transfer to the N terminus of the glycopeptide. Computational docking and molecular dynamics simulations were used to model binding of demethyl-vancomycin aglycone to MtfA. These results demonstrate its utility as a tool for engineering methylated analogs of GPAs.

  13. Synthesis and mode of action of hydrophobic derivatives of the glycopeptide antibiotic eremomycin and des-(N-methyl-D-leucyl)eremomycin against glycopeptide-sensitive and -resistant bacteria.

    PubMed

    Printsevskaya, Svetlana S; Pavlov, Andrey Y; Olsufyeva, Evgenia N; Mirchink, Elena P; Isakova, Elena B; Reznikova, Marina I; Goldman, Robert C; Branstrom, Arthur A; Baizman, Eugene R; Longley, Clifford B; Sztaricskai, Ferenc; Batta, Gyula; Preobrazhenskaya, Maria N

    2002-03-14

    Des-(N-methyl-D-leucyl)eremomycin was obtained by Edman degradation of eremomycin. Derivatives with a hydrophobic substituent at the exterior of the molecule were then synthesized, and their antibacterial activities were compared with similar derivatives of eremomycin. Comparison of derivatives of eremomycin containing the n-decyl or p-(p-chlorophenyl)benzyl substituent in the eremosamine moiety (N') and n-decyl or p-(p-chlorophenyl)benzylamides with similar derivatives of eremomycin possessing the damaged peptide core (a defective binding pocket) showed that compounds of both types are almost equally active against glycopeptide-resistant strains of enterococci (GRE), whereas eremomycin derivatives are more active against staphylococci. Hydrophobic 7d-alkylaminomethylated derivatives of eremomycin (9, 10) demonstrated similar antibacterial properties. Since the basic mode of action of glycopeptide antibiotics involves binding to cell wall intermediates terminating in -D-Ala-D-Ala and this interaction is seriously decreased in the hexapeptide derivatives (lacking the critical N-methyl-D-leucine), we suggest that these hydrophobic derivatives may inhibit peptidoglycan synthesis in the absence of dipeptide binding. NMR binding experiments using Ac-D-Ala-D-Ala show that binding constants of these hexapeptide derivativies are decreased in comparison with the corresponding heptapeptides with intact binding pocket. This is in agreement with the decreased biological activity of the hexapeptide derivatives against vancomycin-sensitive strains in comparison with the activity of parent compounds. Binding to the lactate cell wall analogue Ac-D-Ala-D-Lac with decylamide of eremomycin 8 was not observed, demonstrating that the interaction with this target in GRE does not occur. While hydrophobic glycopeptide derivatives retain the ability to inhibit the synthesis of peptidoglycan in manner of natural glycopeptides, biochemical investigation supports the hypothesis that they

  14. Configurational entropy and cooperativity between ligand binding and dimerization in glycopeptide antibiotics.

    PubMed

    Jusuf, Sutjano; Loll, Patrick J; Axelsen, Paul H

    2003-04-01

    Oligomerization and ligand binding are thermodynamically cooperative processes in many biochemical systems, and the mechanisms giving rise to cooperative behavior are generally attributed to changes in structure. In glycopeptide antibiotics, however, these cooperative processes are not accompanied by significant structural changes. To investigate the mechanism by which cooperativity arises in these compounds, fully solvated molecular dynamics simulations and quasiharmonic normal-mode analysis were performed on chloroeremomycin, vancomycin, and dechlorovancomycin. Configurational entropies were derived from the vibrational modes recovered from ligand-free and ligand-bound forms of the monomeric and dimeric species. Results indicate that both ligand binding and dimerization incur an entropic cost as vibrational activity in the central core of the antibiotic is shifted to higher frequencies with lower amplitudes. Nevertheless, ligand binding and dimerization are cooperative because the entropic cost of both processes occurring together is less than the cost of these processes occurring separately. These reductions in configurational entropy are more than sufficient in magnitude to account for the experimentally observed cooperativity between dimerization and ligand binding. We conclude that biochemical cooperativity can be mediated through changes in vibrational activity, irrespective of the presence or absence of concomitant structural change. This may represent a general mechanism of allostery underlying cooperative phenomena in diverse macromolecular systems. PMID:12656635

  15. In vivo antibacterial activity and pharmacological properties of the membrane-active glycopeptide antibiotic YV11455.

    PubMed

    Yarlagadda, Venkateswarlu; Konai, Mohini M; Manjunath, Goutham B; Prakash, Relekar G; Mani, Bhuvana; Paramanandham, Krishnamoorthy; Ranjan, Shome B; Ravikumar, Raju; Chakraborty, Subhankari P; Roy, Somenath; Haldar, Jayanta

    2015-06-01

    The membrane-active glycopeptide antibiotic YV11455 is a lipophilic cationic vancomycin analogue that demonstrates rapid and concentration-dependent killing of clinically relevant multidrug-resistant (MDR) Gram-positive bacteria in vitro. YV11455 was 2-fold and 54-270-fold more effective than vancomycin against clinical isolates of vancomycin-sensitive and vancomycin-resistant bacteria, respectively. In this study, the in vivo efficacy, pharmacodynamics, pharmacokinetics and acute toxicology of YV11455 were investigated. In vivo activity and pharmacodynamics were determined in the neutropenic mouse thigh infection model against meticillin-resistant Staphylococcus aureus (MRSA). YV11455 produced dose-dependent reductions in MRSA titres in thigh muscle. When administered intravenously, the 50% effective dose (ED(50)) for YV11455 against MRSA was found to be 3.3 mg/kg body weight, and titres were reduced by up to ca. 3log(10)CFU/g from pre-treatment values at a dosage of 12 mg/kg with single treatment. Single-dose pharmacokinetic studies demonstrated linear kinetics and a prolonged half-life, with an increase in drug exposure (area under the concentration-time curve) compared with vancomycin. The peak plasma concentration following an intravenous dose of 12 mg/kg was 543.5 μg/mL. Acute toxicology studies revealed that YV11455 did not cause any significant alterations in biochemical parameters or histological pictures related to major organs such as the liver and kidney at its pharmacodynamic endpoint (ED(3-log kill)). These findings collectively suggest that YV11455 could be used clinically for the treatment of infections caused by MDR Gram-positive bacteria. PMID:25900818

  16. Structure of OxyA tei: completing our picture of the glycopeptide antibiotic producing Cytochrome P450 cascade.

    PubMed

    Haslinger, Kristina; Cryle, Max J

    2016-02-01

    Cyclization of glycopeptide antibiotic precursors occurs in either three or four steps catalyzed by Cytochrome P450 enzymes. Three of these enzymes have been structurally characterized to date with the second enzyme along the pathway, OxyA, escaping structural analysis. We are now able to present the structure of OxyAtei involved in teicoplanin biosynthesis - the same enzyme recently shown to be the first active OxyA homolog. In spite of the hydrophobic character of the teicoplanin precursor, the polar active site of OxyAtei and its affinity for certain azole inhibitors hint at its preference for substrates with polar decorations. PMID:26820384

  17. Anti-biofilm activity and synergism of novel thiazole compounds with glycopeptide antibiotics against multidrug-resistant staphylococci.

    PubMed

    Mohammad, Haroon; Mayhoub, Abdelrahman S; Cushman, Mark; Seleem, Mohamed N

    2015-04-01

    Methicillin-resistant Staphylococcus aureus (MRSA) infections are a leading cause of death among all fatalities caused by antibiotic-resistant bacteria. With the rise of increasing resistance to current antibiotics, new antimicrobials and treatment strategies are urgently needed. Thiazole compounds have been shown to possess potent antimicrobial activity. A lead thiazole 1 and a potent derivative 2 were synthesized and their activity in combination with glycopeptide antibiotics was determined against an array of MRSA and vancomycin-resistant S. aureus (VRSA) clinical isolates. In addition, the anti-biofilm activity of the novel thiazoles was investigated against S. epidermidis. Compound 2 behaved synergistically with vancomycin against MRSA and was able to resensitize VRSA to vancomycin, reducing its MIC by 512-fold in two strains. In addition, both thiazole compounds were superior to vancomycin in significantly reducing S. epidermidis biofilm mass. Collectively, the results obtained demonstrate that compounds 1 and 2 possess potent antimicrobial activity alone or in combination with vancomycin against multidrug-resistant staphylococci and show potential for use in disrupting staphylococcal biofilm. PMID:25315757

  18. Anti-biofilm activity and synergism of novel thiazole compounds with glycopeptide antibiotics against multidrug-resistant staphylococci

    PubMed Central

    Mohammad, Haroon; Mayhoub, Abdelrahman S.; Cushman, Mark; Seleem, Mohamed N.

    2015-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) infections are a leading cause of death among all fatalities caused by antibiotic-resistant bacteria. With the rise of increasing resistance to current antibiotics, new antimicrobials and treatment strategies are urgently needed. Thiazole compounds have been shown to possess potent antimicrobial activity. A lead thiazole 1 and a potent derivative 2 were synthesized and their activity in combination with glycopeptide antibiotics was determined against an array of MRSA and vancomycin-resistant Staphylococcus aureus (VRSA) clinical isolates. Additionally, the anti-biofilm activity of the novel thiazoles was investigated against Staphylococcus epidermidis. Compound 2 behaved synergistically with vancomycin against MRSA and was able to re-sensitize VRSA to vancomycin, reducing its minimum inhibitory concentration (MIC) by 512-fold in two strains. Additionally, both thiazole compounds were superior to vancomycin in significantly reducing S. epidermidis biofilm mass. Collectively the results obtained demonstrate compounds 1 and 2 possess potent antimicrobial activity alone or in combination with vancomycin against multidrug-resistant staphylococci and show potential for use in disrupting staphylococcal biofilm. PMID:25315757

  19. Antibiotics in Animal Products

    NASA Astrophysics Data System (ADS)

    Falcão, Amílcar C.

    The administration of antibiotics to animals to prevent or treat diseases led us to be concerned about the impact of these antibiotics on human health. In fact, animal products could be a potential vehicle to transfer drugs to humans. Using appropri ated mathematical and statistical models, one can predict the kinetic profile of drugs and their metabolites and, consequently, develop preventive procedures regarding drug transmission (i.e., determination of appropriate withdrawal periods). Nevertheless, in the present chapter the mathematical and statistical concepts for data interpretation are strictly given to allow understanding of some basic pharma-cokinetic principles and to illustrate the determination of withdrawal periods

  20. In Vitro Activity of TD-1792, a Multivalent Glycopeptide-Cephalosporin Antibiotic, against 377 Strains of Anaerobic Bacteria and 34 Strains of Corynebacterium Species

    PubMed Central

    Citron, Diane M.; Warren, Yumi A.; Goldstein, Ellie J. C.

    2012-01-01

    TD-1792 is a multivalent glycopeptide-cephalosporin heterodimer antibiotic with potent activity against Gram-positive bacteria. We tested TD-1792 against 377 anaerobes and 34 strains of Corynebacterium species. Against nearly all Gram-positive strains, TD-1792 had an MIC90 of 0.25 μg/ml and was typically 3 to 7 dilutions more active than vancomycin and daptomycin. PMID:22290981

  1. Antibiotic use in livestock production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antibiotic usage is a useful and commonly implemented practice in livestock and production agriculture that has progressively gained attention in recent years from consumers of animal products due to concerns about human and environmental health. Sub-therapeutic usage of antibiotics has led to a con...

  2. Expedient antibiotics production: Final report

    SciTech Connect

    Bienkowski, P.R.; Byers, C.H.; Lee, D.D.

    1988-05-01

    The literature on the manufacture, separation and purification, and clinical uses of antibiotics was reviewed, and a bibliography of the pertinent material was completed. Five antimicrobial drugs, penicillin V and G, (and amoxicillin with clavulanic acid), Cephalexin (a cephalosporin), tetracycline and oxytetracycline, Bacitracin (topical), and sulfonamide (chemically produced) were identified for emergency production. Plants that manufacture antibiotics in the continental United States, Mexico, and Puerto Rico have been identified along with potential alternate sites such as those where SCP, enzyme, and fermentation ethanol are produced. Detailed process flow sheets and process descriptions have been derived from the literature and documented. This investigation revealed that a typical antibiotic-manufacturing facility is composed of two main sections: (1) a highly specialized, but generic, fermentation unit and (2) a multistep, complex separation and purification unit which is specific to a particular antibiotic product. The fermentation section requires specialized equipment for operation in a sterile environment which is not usually available in other industries. The emergency production of antibiotics under austere conditions will be feasible only if a substantial reduction in the complexity and degree of separation and purity normally required can be realized. Detailed instructions were developed to assist state and federal officials who would be directing the resumption of antibiotic production after a nuclear attack. 182 refs., 54 figs., 26 tabs.

  3. Current perspectives on glycopeptide resistance.

    PubMed Central

    Woodford, N; Johnson, A P; Morrison, D; Speller, D C

    1995-01-01

    In the last 5 years, clinical isolates of gram-positive bacteria with intrinsic or acquired resistance to glycopeptide antibiotics have been encountered increasingly. In many of these isolates, resistance arises from an alteration of the antibiotic target site, with the terminal D-alanyl-D-alanine moiety of peptidoglycan precursors being replaced by groups that do not bind glycopeptides. Although the criteria for defining resistance have been revised frequently, the reliable detection of low-level glycopeptide resistance remains problematic and is influenced by the method chosen. Glycopeptide-resistant enterococci have emerged as a particular problem in hospitals, where in addition to sporadic cases, clusters of infections with evidence of interpatient spread have occurred. Studies using molecular typing methods have implicated colonization of patients, staff carriage, and environmental contamination in the dissemination of these bacteria. Choice of antimicrobial therapy for infections caused by glycopeptide-resistant bacteria may be complicated by resistance to other antibiotics. Severe therapeutic difficulties are being encountered among patients infected with enterococci, with some infections being untreatable with currently available antibiotics. PMID:8665471

  4. Heterologous expression in Escherichia coli of the first module of the nonribosomal peptide synthetase for chloroeremomycin, a vancomycin-type glycopeptide antibiotic.

    PubMed

    Trauger, J W; Walsh, C T

    2000-03-28

    The gene cluster from Amycolotopsis orientalis responsible for biosynthesis of the vancomycin-type glycopeptide antibiotic chloroeremomycin was recently sequenced, indicating that this antibiotic derives from a seven-residue peptide synthesized by a three-subunit (CepA, CepB, and CepC) modular nonribosomal peptide synthetase. Expression of all or parts of the peptide synthetase in Escherichia coli would facilitate biochemical characterization of its substrate specificity, an important step toward the development of more potent glycopeptides by combinatorial biosynthesis. To determine whether CepA, a three-module 3,158-residue peptide synthetase expected to assemble the first three residues of the heptapeptide precursor, could be heterologously expressed in E. coli and converted to active, holo form by posttranslational priming with a phosphopantetheinyltransferase, we expressed two CepA fragments (CepA1-575 and CepA1-1596) as well as full-length CepA (CepA1-3158). All three constructs were expressed in soluble form. We find that the CepA1-575 fragment, containing adenylation and peptidyl carrier protein domains (A1-PCP1), specifically adenylates l-leucine and d-leucine in a 6:1 ratio, and it can be converted to holo form by the phosphopantetheinyltransferase Sfp; also, we find that holo-CepA1-575 can be covalently aminoacylated with l-leucine on the peptidyl carrier protein 1 domain. However, no amino acid-dependent adenylation or aminoacylation activity was detected for the larger CepA constructs with l-leucine or other expected amino acid substrates, suggesting severe folding problems in the multidomain proteins. PMID:10716695

  5. A few atoms make the difference: synthetic, CD, NMR and computational studies on antiviral and antibacterial activities of glycopeptide antibiotic aglycon derivatives.

    PubMed

    Bereczki, Ilona; Mándi, Attila; Rőth, Erzsébet; Borbás, Anikó; Fizil, Ádám; Komáromi, István; Sipos, Attila; Kurtán, Tibor; Batta, Gyula; Ostorházi, Eszter; Rozgonyi, Ferenc; Vanderlinden, Evelien; Naesens, Lieve; Sztaricskai, Ferenc; Herczegh, Pál

    2015-04-13

    Despite the close structural similarity between the heptapeptide cores of the glycopeptide antibiotics teicoplanin and ristocetin, synthetically modified derivatives of their aglycons show significantly different antibacterial and antiviral properties. The teicoplanin aglycon derivatives with one exception proved to be potent antibacterials but they did not exhibit anti-influenza virus activity. In contrast, the aglycoristocetin derivatives generally showed high anti-influenza virus activity and possessed moderate antibacterial activity. A systematic structure-activity relationship study has been carried out on ristocetin and teicoplanin aglycon derivatives, to explore which structural differences are responsible for these markedly different biological activities. According to electronic circular dichroism and in silico conformational studies, it was found that the differences in anti-influenza virus activity are mainly determined by the conformation of the heptapeptide core of the antibiotics controlled by the presence or absence of chloro substituents. Knowledge of the bioactive conformation will help to design new analogs with improved anti-influenza virus activity. For the teicoplanin derivatives, it was shown that derivatization to improve the antiviral efficacy was accompanied by a significant decrease in antibacterial activity. PMID:25752526

  6. Classification of Nonomuraea sp. ATCC 39727, an actinomycete that produces the glycopeptide antibiotic A40926, as Nonomuraea gerenzanensis sp. nov.

    PubMed

    Dalmastri, Claudia; Gastaldo, Luciano; Marcone, Giorgia Letizia; Binda, Elisa; Congiu, Terenzio; Marinelli, Flavia

    2016-02-01

    Strain ATCC 39727, which produces the antibiotic A40926 (the natural precursor of the antibiotic dalbavancin), was isolated from a soil sample collected in India, and it was originally classified as a member of the genus Actinomadura on the base of morphology and cell-wall composition. A phylogenetic analysis based on 16S rRNA gene sequences indicates that the strain forms a distinct clade within the genus Nonomuraea, and it is most closely related to Nonomuraea angiospora DSM 43173T (98.72 % similarity) and Nonomuraea jabiensis A4036T (98.69 %). The strain forms an extensively branched substrate mycelium and aerial hyphae that form spiral chains of spores with ridged surfaces. The cell wall contains meso-diaminopimelic acid and the whole-cell sugars are glucose, ribose, galactose, mannose and madurose (madurose as the diagnostic sugar). The N-acyl type of muramic acid is acetyl. The predominant menaquinone is MK-9(H4), with minor amounts of MK-9(H2), MK-9(H6) and MK-9(H0). The polar-lipid profile includes diphosphatidylglycerol, phosphatidylethanolamine, hydroxyphosphatidylethanolamine, phosphatidylmethylethanolamine, hydroxyphosphatidylmethylethanolamine, phosphatidylinositol and a series of uncharacterized phospholipids, glycolipids and phosphoglycolipids. The major cellular fatty acids are iso-C16 : 0 and 10-methyl C17 : 0. The genomic DNA G+C content is 71.2 mol%. Significant differences in the morphological, chemotaxonomic and biochemical data, together with DNA-DNA relatedness between strain ATCC 39727 and closely related type strains, clearly demonstrated that strain ATCC 39727 represents a novel species of the genus Nonomuraea, for which the name Nonomuraea gerenzanensis sp. nov. is proposed. The type strain is ATCC 39727T ( = DSM 100948T). PMID:26944798

  7. CNS active O-linked glycopeptides

    PubMed Central

    Jones, Evan M.; Polt, Robin

    2015-01-01

    Naturally occurring glycopeptides and glycoproteins play important roles in biological processes. Glycosylation is one of the most common post-translational modifications in vivo. Glycopeptides are involved in cell signaling and sorting, providing cell surface markers for recognition. From the drug design and synthesis perspective, modification of a peptide through glycosylation results in increased bioavailability and bioactivity of glycopeptides in living systems with negligible toxicity of degradation products. Glycopeptide synthesis can be accomplished through incorporation of a glycosylated amino acid in solid phase peptide synthesis (SPPS) to form the desired peptide, or via incorporation of sugar-amino acid moieties. Additionally, research indicates that glycosylation increases penetration of the blood-brain barrier (BBB) by peptides, which may lead to novel therapeutics for neurological disorders. Recent applications of glycopeptides have focused on the in vivo central nervous system (CNS) effects after peripheral administration of centrally active peptides modified with various carbohydrates. PMID:26157795

  8. In Vivo Characterization of the Activation and Interaction of the VanR-VanS Two-Component Regulatory System Controlling Glycopeptide Antibiotic Resistance in Two Related Streptomyces Species

    PubMed Central

    Novotna, Gabriela Balikova; Kwun, Min Jung

    2015-01-01

    The VanR-VanS two-component system is responsible for inducing resistance to glycopeptide antibiotics in various bacteria. We have performed a comparative study of the VanR-VanS systems from two streptomyces strains, Streptomyces coelicolor and Streptomyces toyocaensis, to characterize how the two proteins cooperate to signal the presence of antibiotics and to define the functional nature of each protein in each strain background. The results indicate that the glycopeptide antibiotic inducer specificity is determined solely by the differences between the amino acid sequences of the VanR-VanS two-component systems present in each strain rather than by any inherent differences in general cell properties, including cell wall structure and biosynthesis. VanR of S. coelicolor (VanRsc) functioned with either sensor kinase partner, while VanR of S. toyocaensis (VanRst) functioned only with its cognate partner, S. toyocaensis VanS (VanSst). In contrast to VanRsc, which is known to be capable of phosphorylation by acetylphosphate, VanRst could not be activated in vivo independently of a VanS sensor kinase. A series of amino acid sequence modifications changing residues in the N-terminal receiver (REC) domain of VanRst to the corresponding residues present in VanRsc failed to create a protein capable of being activated by VanS of S. coelicolor (VanSsc), which suggests that interaction of the response regulator with its cognate sensor kinase may require a region more extended than the REC domain. A T69S amino acid substitution in the REC domain of VanRst produced a strain exhibiting weak constitutive resistance, indicating that this particular amino acid may play a key role for VanS-independent phosphorylation in the response regulator protein. PMID:26711760

  9. Glycopeptide Antibiotics Potently Inhibit Cathepsin L in the Late Endosome/Lysosome and Block the Entry of Ebola Virus, Middle East Respiratory Syndrome Coronavirus (MERS-CoV), and Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV).

    PubMed

    Zhou, Nan; Pan, Ting; Zhang, Junsong; Li, Qianwen; Zhang, Xue; Bai, Chuan; Huang, Feng; Peng, Tao; Zhang, Jianhua; Liu, Chao; Tao, Liang; Zhang, Hui

    2016-04-22

    Ebola virus infection can cause severe hemorrhagic fever with a high mortality in humans. The outbreaks of Ebola viruses in 2014 represented the most serious Ebola epidemics in history and greatly threatened public health worldwide. The development of additional effective anti-Ebola therapeutic agents is therefore quite urgent. In this study, via high throughput screening of Food and Drug Administration-approved drugs, we identified that teicoplanin, a glycopeptide antibiotic, potently prevents the entry of Ebola envelope pseudotyped viruses into the cytoplasm. Furthermore, teicoplanin also has an inhibitory effect on transcription- and replication-competent virus-like particles, with an IC50 as low as 330 nm Comparative analysis further demonstrated that teicoplanin is able to block the entry of Middle East respiratory syndrome (MERS) and severe acute respiratory syndrome (SARS) envelope pseudotyped viruses as well. Teicoplanin derivatives such as dalbavancin, oritavancin, and telavancin can also inhibit the entry of Ebola, MERS, and SARS viruses. Mechanistic studies showed that teicoplanin blocks Ebola virus entry by specifically inhibiting the activity of cathepsin L, opening a novel avenue for the development of additional glycopeptides as potential inhibitors of cathepsin L-dependent viruses. Notably, given that teicoplanin has routinely been used in the clinic with low toxicity, our work provides a promising prospect for the prophylaxis and treatment of Ebola, MERS, and SARS virus infection. PMID:26953343

  10. The Biogeography of Putative Microbial Antibiotic Production.

    PubMed

    Morlon, Hélène; O'Connor, Timothy K; Bryant, Jessica A; Charkoudian, Louise K; Docherty, Kathryn M; Jones, Evan; Kembel, Steven W; Green, Jessica L; Bohannan, Brendan J M

    2015-01-01

    Understanding patterns in the distribution and abundance of functional traits across a landscape is of fundamental importance to ecology. Mapping these distributions is particularly challenging for species-rich groups with sparse trait measurement coverage, such as flowering plants, insects, and microorganisms. Here, we use likelihood-based character reconstruction to infer and analyze the spatial distribution of unmeasured traits. We apply this framework to a microbial dataset comprised of 11,732 ketosynthase alpha gene sequences extracted from 144 soil samples from three continents to document the spatial distribution of putative microbial polyketide antibiotic production. Antibiotic production is a key competitive strategy for soil microbial survival and performance. Additionally, novel antibiotic discovery is highly relevant to human health, making natural antibiotic production by soil microorganisms a major target for bioprospecting. Our comparison of trait-based biogeographical patterns to patterns based on taxonomy and phylogeny is relevant to our basic understanding of microbial biogeography as well as the pressing need for new antibiotics. PMID:26102275

  11. The Biogeography of Putative Microbial Antibiotic Production

    PubMed Central

    Bryant, Jessica A.; Charkoudian, Louise K.; Docherty, Kathryn M.; Jones, Evan; Kembel, Steven W.; Green, Jessica L.; Bohannan, Brendan J. M.

    2015-01-01

    Understanding patterns in the distribution and abundance of functional traits across a landscape is of fundamental importance to ecology. Mapping these distributions is particularly challenging for species-rich groups with sparse trait measurement coverage, such as flowering plants, insects, and microorganisms. Here, we use likelihood-based character reconstruction to infer and analyze the spatial distribution of unmeasured traits. We apply this framework to a microbial dataset comprised of 11,732 ketosynthase alpha gene sequences extracted from 144 soil samples from three continents to document the spatial distribution of putative microbial polyketide antibiotic production. Antibiotic production is a key competitive strategy for soil microbial survival and performance. Additionally, novel antibiotic discovery is highly relevant to human health, making natural antibiotic production by soil microorganisms a major target for bioprospecting. Our comparison of trait-based biogeographical patterns to patterns based on taxonomy and phylogeny is relevant to our basic understanding of microbial biogeography as well as the pressing need for new antibiotics. PMID:26102275

  12. Biologically Relevant Glycopeptides: Synthesis and Applications

    NASA Astrophysics Data System (ADS)

    Bennett, Clay S.; Payne, Richard J.; Koeller, Kathryn M.; Wong, Chi-Huey

    Over the past two decades interest in glycopeptides and glycoproteins has intensified, due in part to the development of new and efficient methods for the synthesis of these compounds. This includes a number of chemical and enzymatic techniques for incorporating glycosylation onto the peptide backbone as well as the introduction of powerful peptide ligation methods for the construction of glycoproteins. This review discusses these methods with a special emphasis on biologically relevant glycopeptides and glycoproteins. This includes the development of a number of antigens which hold promise as potential vaccines for HIV, cancer, or a host of other clinically important diseases. In addition the development of new antibiotics aimed at overcoming the problem of resistance will be discussed. Finally, chemical and enzymatic methods for the construction of glycopeptide mimetics will be described.

  13. Beta-glucan-depleted, glycopeptide-rich extracts from Brewer's and Baker's yeast (Saccharomyces cerevisiae) lower interferon-gamma production by stimulated human blood cells in vitro.

    PubMed

    Williams, Roderick; Dias, Daniel A; Jayasinghe, Nirupama; Roessner, Ute; Bennett, Louise E

    2016-04-15

    Regulation of the human immune system requires controlled pro- and anti-inflammatory responses for host defence against infection and disease states. Yeasts (Saccharomyces cerevisiae), as used in brewing and baking, are mostly known for ability to stimulate the human immune-system predominantly reflecting the pro-inflammatory cell wall β-glucans. However, in this study, using food-compatible processing methods, glycopeptide-enriched and β-glucan-depleted products were each prepared from Brewer's and Baker's yeasts, which suppressed production of interferon-γ (IFN-γ) in human whole blood cell assay, signifying that anti-inflammatory factors are also present in yeast. Anti-inflammatory bioactivities of products prepared from Brewer's and Baker's yeast were compared with the commercial yeast product, Epicor®. While unfractionated Epicor was inactive, the C18 resin-binding fractions of Brewer's and Baker's yeast products and Epicor dose-dependently lowered IFN-γ, demonstrating that Epicor also contained both pro-inflammatory (β-glucans) and anti-inflammatory components. Anti-inflammatory activity was attributed to C18 resin-binding species glyco-peptides in Epicor and experimental yeast products. This study demonstrated that pro- and anti-inflammatory factors could be resolved and enriched in yeasts by suitable processing, with potential to improve specific activities. PMID:26617014

  14. Editorial: advances in therapeutic glycopeptides.

    PubMed

    Zeng, Wenbin; Chen, Yue-Lei

    2014-01-01

    Glycopeptides, peptides containing sugar β-amino acids, have significant impact on medicinal chemistry research and pharmaceutical industr. In 1956, the discovery of one classic glycopeptide, vancomycin, broke the dawn of a new age for antibacterial research. Employing glycopeptides for the therapeutic purposes used to be regarded as proposals. Owing largely to the recent improvements in separation practices, characterization techniques, synthetic methods, and biological research, these proposals have been transformed into ongoing research projects in many laboratories around the world. Previously known as antibiotics, glycopeptides have been used as chemotherapeutic, antiviral, antitubercular, antifungal, antiproliferative and apoptotic agents. Nowadays they are even considered for the development of HIV and cancer vaccines. While several of them are in clinical trials, it could be expected that in the near future, treatment regimen of such difficult diseases might be reformed accordingly. Many interesting preliminary results are being produced in this emerging area. As witnesses and practitioners in this exciting area, however, we notice that the related communication in public domain is still limited due to the relatively small number of researchers involved. Thus, we feel the necessity to compile a timely issue about the special topic "Advances in Therapeutic Glycopeptides", covering state-of-the-art research papers and expert reviews from this area. We are glad that Protein & Peptide Letters is willing to realize the idea with us. The opening paper of this issue by Dr. Voglmeir and coauthor discusses three types of PNGases in respect of their general properties and applications of the commercially available PNGases in glycopeptide and glycoprotein analysis. Dr. Liu and coauthors describe current techniques such as high-performance liquid chromatography (HPLC), capillary electrophoresis (CE), and mass spectrometry (MS), for the characterization of

  15. Environmental impacts of antibiotic use in the animal production industry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antibiotics are routinely used in the livestock industry to treat and prevent disease. At subtherapeutic concentrations, antibiotics can select for resistant bacteria in the gastrointestinal tract of production animals, providing a potential reservoir for dissemination of drug resistant bacteria int...

  16. Physics and the production of antibiotics

    NASA Astrophysics Data System (ADS)

    Fairbrother, Robert; Riddle, Wendy; Fairbrother, Neil

    2006-01-01

    This article is the first in a series that describe some of the physics involved in the production of antibiotics. The field is often referred to as biochemical engineering but this does not indicate the considerable part played by physics and physicists. It is a process that undergoes continual research and development. Penicillin has been selected for the focus of this article, although the engineering principles and underlying physics apply to the production of other microbial products such as amino acids (which can be used as food additives), bulk chemicals such as ethanol (used in everything from hair spray and aftershave to solvents for paints and explosives) and the well-known processes of brewing and baking. In this article the application of physics to the design of the fermenter—the giant vessel in which the production of these products occurs—is discussed.

  17. CNS Active O-Linked Glycopeptides that Penetrate the BBB

    NASA Astrophysics Data System (ADS)

    Jones, Evan; Polt, Robin

    2015-06-01

    Naturally occurring glycopeptides and glycoproteins play important roles in biological processes. Glycosylation is one of the most common post-translational modifications in vivo. Glycopeptides are involved in cell signaling and sorting, providing cell surface markers for recognition. From the drug design and synthesis perspective, modification of a peptide through glycosylation results in increased bioavailability and bioactivity of glycopeptides in living systems with negligible toxicity of degradation products. Glycopeptide synthesis can be accomplished through incorporation of a glycosylated amino acid in solid phase peptide synthesis (SPPS) to form the desired peptide, or via incorporation of sugar-amino acid moieties. Additionally, research indicates that glycosylation increases penetration of the blood-brain barrier (BBB) by peptides, which may lead to novel therapeutics for neurological disorders. Recent applications of glycopeptides have focused on the in vivo central nervous system effects after peripheral administration of centrally active peptides modified with various carbohydrates.

  18. Botanical alternatives to antibiotics for use in organic poultry production.

    PubMed

    Diaz-Sanchez, Sandra; D'Souza, Doris; Biswas, Debrabrata; Hanning, Irene

    2015-06-01

    The development of antibiotic resistant pathogens has resulted from the use of sub-therapeutic concentrations of antibiotics delivered in poultry feed. Furthermore, there are a number of consumer concerns regarding the use of antibiotics in food animals including residue contamination of poultry products and antibiotic resistant bacterial pathogens. These issues have resulted in recommendations to reduce the use of antibiotics as growth promoters in livestock in the United States. Unlike conventional production, organic systems are not permitted to use antibiotics. Thus, both conventional and organic poultry production need alternative methods to improve growth and performance of poultry. Herbs, spices, and various other plant extracts are being evaluated as alternatives to antibiotics and some do have growth promoting effects, antimicrobial properties, and other health-related benefits. This review aims to provide an overview of herbs, spices, and plant extracts, currently defined as phytobiotics as potential feed additives. PMID:25743421

  19. Antibiotics in Canadian poultry productions and anticipated alternatives.

    PubMed

    Diarra, Moussa S; Malouin, François

    2014-01-01

    The use of antibiotics in food-producing animals has significantly increased animal health by lowering mortality and the incidence of diseases. Antibiotics also have largely contributed to increase productivity of farms. However, antibiotic usage in general and relevance of non-therapeutic antibiotics (growth promoters) in feed need to be reevaluated especially because bacterial pathogens of humans and animals have developed and shared a variety of antibiotic resistance mechanisms that can easily be spread within microbial communities. In Canada, poultry production involves more than 2600 regulated chicken producers who have access to several antibiotics approved as feed additives for poultry. Feed recipes and mixtures vary greatly geographically and from one farm to another, making links between use of a specific antibiotic feed additive and production yields or selection of specific antibiotic-resistant bacteria difficult to establish. Many on-farm studies have revealed the widespread presence of antibiotic-resistant bacteria in broiler chickens. While some reports linked the presence of antibiotic-resistant organisms to the use of feed supplemented with antibiotics, no recent studies could clearly demonstrate the benefit of antimicrobial growth promoters on performance and production yields. With modern biosecurity and hygienic practices, there is a genuine concern that intensive utilization of antibiotics or use of antimicrobial growth promoters in feed might no longer be useful. Public pressure and concerns about food and environmental safety (antibiotic residues, antibiotic-resistant pathogens) have driven researchers to actively look for alternatives to antibiotics. Some of the alternatives include pre- and probiotics, organic acids and essential oils. We will describe here the properties of some bioactive molecules, like those found in cranberry, which have shown interesting polyvalent antibacterial and immuno-stimulatory activities. PMID:24987390

  20. Antibiotics in Canadian poultry productions and anticipated alternatives

    PubMed Central

    Diarra, Moussa S.; Malouin, François

    2014-01-01

    The use of antibiotics in food-producing animals has significantly increased animal health by lowering mortality and the incidence of diseases. Antibiotics also have largely contributed to increase productivity of farms. However, antibiotic usage in general and relevance of non-therapeutic antibiotics (growth promoters) in feed need to be reevaluated especially because bacterial pathogens of humans and animals have developed and shared a variety of antibiotic resistance mechanisms that can easily be spread within microbial communities. In Canada, poultry production involves more than 2600 regulated chicken producers who have access to several antibiotics approved as feed additives for poultry. Feed recipes and mixtures vary greatly geographically and from one farm to another, making links between use of a specific antibiotic feed additive and production yields or selection of specific antibiotic-resistant bacteria difficult to establish. Many on-farm studies have revealed the widespread presence of antibiotic-resistant bacteria in broiler chickens. While some reports linked the presence of antibiotic-resistant organisms to the use of feed supplemented with antibiotics, no recent studies could clearly demonstrate the benefit of antimicrobial growth promoters on performance and production yields. With modern biosecurity and hygienic practices, there is a genuine concern that intensive utilization of antibiotics or use of antimicrobial growth promoters in feed might no longer be useful. Public pressure and concerns about food and environmental safety (antibiotic residues, antibiotic-resistant pathogens) have driven researchers to actively look for alternatives to antibiotics. Some of the alternatives include pre- and probiotics, organic acids and essential oils. We will describe here the properties of some bioactive molecules, like those found in cranberry, which have shown interesting polyvalent antibacterial and immuno-stimulatory activities. PMID:24987390

  1. Development of a Fourier transform infrared spectroscopy coupled to UV-Visible analysis technique for aminosides and glycopeptides quantitation in antibiotic locks.

    PubMed

    Sayet, G; Sinegre, M; Ben Reguiga, M

    2014-01-01

    Antibiotic Lock technique maintains catheters' sterility in high-risk patients with long-term parenteral nutrition. In our institution, vancomycin, teicoplanin, amikacin and gentamicin locks are prepared in the pharmaceutical department. In order to insure patient safety and to comply to regulatory requirements, antibiotic locks are submitted to qualitative and quantitative assays prior to their release. The aim of this study was to develop an alternative quantitation technique for each of these 4 antibiotics, using a Fourier transform infrared (FTIR) coupled to UV-Visible spectroscopy and to compare results to HPLC or Immunochemistry assays. Prevalidation studies permitted to assess spectroscopic conditions used for antibiotic locks quantitation: FTIR/UV combinations were used for amikacin (1091-1115cm(-1) and 208-224nm), vancomycin (1222-1240cm(-1) and 276-280nm), and teicoplanin (1226-1230cm(-1) and 278-282nm). Gentamicin was quantified with FTIR only (1045-1169cm(-1) and 2715-2850cm(-1)) due to interferences in UV domain of parabens, preservatives present in the commercial brand used to prepare locks. For all AL, the method was linear (R(2)=0.996 to 0.999), accurate, repeatable (intraday RSD%: from 2.9 to 7.1% and inter-days RSD%: 2.9 to 5.1%) and precise. Compared to the reference methods, the FTIR/UV method appeared tightly correlated (Pearson factor: 97.4 to 99.9%) and did not show significant difference in recovery determinations. We developed a new simple reliable analysis technique for antibiotics quantitation in locks using an original association of FTIR and UV analysis, allowing a short time analysis to identify and quantify the studied antibiotics. PMID:24438668

  2. Efforts to slacken antibiotic resistance: Labeling meat products from animals raised without antibiotics in the United States.

    PubMed

    Centner, Terence J

    2016-09-01

    As bacteria and diseases spread due to climatic change, greater amounts of antibiotics will be used thereby exacerbating the problem of antibiotic resistance. To help slacken the development of resistant bacteria, the medical community is attempting to reduce unnecessary and excessive usage of antibiotics. One of the targets is the use of antibiotics for enhancing animal growth and promoting feed efficiency in the production of food animals. While governments can adopt regulations prohibiting nontherapeutic uses of antibiotics in food animals and strategies to reduce antibiotic usage, another idea is to publicize when antibiotics are used in food animal production by allowing labeled meat products. This paper builds upon existing labeling and marketing efforts in the United States to show how a government can develop a verified antibiotic-free labeling program that would allow consumers to purchase meat products from animals that had never received antibiotics. PMID:27236477

  3. Physics and the Production of Antibiotics: 2

    ERIC Educational Resources Information Center

    Fairbrother, Robert; Riddle, Wendy; Fairbrother, Neil

    2006-01-01

    In an article in the preceding issue we discussed the design and construction of fermenters in which antibiotics are cultured. For industrial purposes these fermenters can range in size up to 500 m[cube]. They have to be sterilized, filled with sterile culture medium and the culture itself and supplied with oxygen continuously. In some cases they…

  4. 21 CFR 333.150 - Labeling of first aid antibiotic drug products.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Labeling of first aid antibiotic drug products... First Aid Antibiotic Drug Products § 333.150 Labeling of first aid antibiotic drug products. (a... identifies the product as a “first aid antibiotic.” (b) Indications. The labeling of the product...

  5. 21 CFR 333.150 - Labeling of first aid antibiotic drug products.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 5 2012-04-01 2012-04-01 false Labeling of first aid antibiotic drug products... First Aid Antibiotic Drug Products § 333.150 Labeling of first aid antibiotic drug products. (a... identifies the product as a “first aid antibiotic.” (b) Indications. The labeling of the product...

  6. 21 CFR 333.150 - Labeling of first aid antibiotic drug products.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 5 2013-04-01 2013-04-01 false Labeling of first aid antibiotic drug products... First Aid Antibiotic Drug Products § 333.150 Labeling of first aid antibiotic drug products. (a... identifies the product as a “first aid antibiotic.” (b) Indications. The labeling of the product...

  7. 21 CFR 333.150 - Labeling of first aid antibiotic drug products.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 5 2011-04-01 2011-04-01 false Labeling of first aid antibiotic drug products... First Aid Antibiotic Drug Products § 333.150 Labeling of first aid antibiotic drug products. (a... identifies the product as a “first aid antibiotic.” (b) Indications. The labeling of the product...

  8. Different classes of antibiotics differentially influence shiga toxin production.

    PubMed

    McGannon, Colleen Marie; Fuller, Cynthia Ann; Weiss, Alison Ann

    2010-09-01

    Shiga toxin (Stx) in Escherichia coli O157:H7 is encoded as a late gene product by temperate bacteriophage integrated into the chromosome. Phage late genes, including stx, are silent in the lysogenic state. However, stress signals, including some induced by antibiotics, trigger the phage to enter the lytic cycle, and phage replication and Stx production occur concurrently. In addition to the Stx produced by O157:H7, phage produced by O157:H7 can infect harmless intestinal E. coli and recruit them to produce Shiga toxin. To understand how antibiotics influence Stx production, Stx lysogens were treated with different classes of antibiotics in the presence or absence of phage-sensitive E. coli, and Stx-mediated inhibition of protein synthesis was monitored using luciferase-expressing Vero cells. Growth-inhibitory levels of antibiotics suppressed Stx production. Subinhibitory levels of antibiotics that target DNA synthesis, including ciprofloxacin (CIP) and trimethoprim-sulfamethoxazole, increased Stx production, while antibiotics that target the cell wall, transcription, or translation did not. More Stx was produced when E. coli O157:H7 was incubated in the presence of phage-sensitive E. coli than when grown as a pure culture. Remarkably, very high levels of Stx were detected even when growth of O157:H7 was completely suppressed by CIP. In contrast, azithromycin significantly reduced Stx levels even when O157:H7 viability remained high. PMID:20585113

  9. Counteraction of antibiotic production and degradation stabilizes microbial communities

    PubMed Central

    Kelsic, Eric D.; Zhao, Jeffrey; Vetsigian, Kalin; Kishony, Roy

    2015-01-01

    Summary A major challenge in theoretical ecology is understanding how natural microbial communities support species diversity1-8, and in particular how antibiotic producing, sensitive and resistant species coexist9-15. While cyclic “rock-paper-scissors” interactions can stabilize communities in spatial environments9-11, coexistence in unstructured environments remains an enigma12,16. Here, using simulations and analytical models, we show that the opposing actions of antibiotic production and degradation enable coexistence even in well-mixed environments. Coexistence depends on 3-way interactions where an antibiotic degrading species attenuates the inhibitory interactions between two other species. These 3-way interactions enable coexistence that is robust to substantial differences in inherent species growth rates and to invasion by “cheating” species that cease producing or degrading antibiotics. At least two antibiotics are required for stability, with greater numbers of antibiotics enabling more complex communities and diverse dynamical behaviors ranging from stable fixed-points to limit cycles and chaos. Together, these results show how multi-species antibiotic interactions can generate ecological stability in both spatial and mixed microbial communities, suggesting strategies for engineering synthetic ecosystems and highlighting the importance of toxin production and degradation for microbial biodiversity. PMID:25992546

  10. Specificity of induction of glycopeptide resistance genes in Enterococcus faecalis.

    PubMed Central

    Baptista, M; Depardieu, F; Courvalin, P; Arthur, M

    1996-01-01

    Regulation of VanA- and VanB-type glycopeptide resistance in enterococci is mediated by related two-component regulatory systems (VanR-VanS and VanRB-VanSB). The transglycosylase inhibitors vancomycin, teicoplanin, and moenomycin induced synthesis of the VanX D,D-dipeptidase in a VanA-type Enterococcus faecalis harboring transposon Tn1546. Inhibitors of reactions immediately preceding (ramoplanin) or following (penicillin G and bacitracin) transglycosylation were not inducers. These results identify accumulation of membrane-bound lipid intermediate II as a potential signal for induction of VanA-type resistance. In E.faecalis BM4281 harboring a wild vanB genetic element, D,D-dipeptidase synthesis was only inducible by vancomycin. Induction of the production of the VanB ligase by vancomycin was required for growth of a vancomycin-dependent derivative of BM4281, since introduction of a plasmid coding for constitutive synthesis of the VanA ligase eliminated the requirement of glycopeptide for growth. Both vancomycin and teicoplanin were able to induce D,D-dipeptidase synthesis in BM4281 derivatives that were vancomycin and teicoplanin resistant or vancomycin and teicoplanin dependent. Acquisition of teicoplanin resistance in the latter types of strains was due to alteration in induction specificity associated with an increase in the sensitivity of the regulatory system to vancomycin. Thus, the wild VanRB-VanSB system is unable or not sensitive enough to sense teicoplanin, although mutations can lead to recognition of this antibiotic. PMID:8891132

  11. Antibiotics

    MedlinePlus

    ... or not using them properly, can add to antibiotic resistance. This happens when bacteria change and become able ... survive and re-infect you. Do not save antibiotics for later or use someone else's prescription. Centers for Disease Control and Prevention

  12. Controlled Antibiotic use during Fuel Ethanol Production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The production of fuel ethanol from corn feedstock is a rapidly growing industry in the US. The ability to make a profit in ethanol production from corn is marginal, and depends heavily on the sale of byproducts of the fermentation process. The fermentation reaction is optimized for yeast growth a...

  13. Background antibiotic resistance patterns in antibiotic-free pastured poultry production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antibiotic resistance (AR) is a significant public health issue, and agroecosystems are often viewed as major environmental sources of antibiotic resistant foodborne pathogens. While the use of antibiotics in agroecosystems can potentially increase AR, appropriate background resistance levels in th...

  14. Screening and productivity of penicillin antibiotic from Penicillium sp.

    PubMed

    Sivakumari, V; Dhinakaran, J; Rajendran, A

    2009-10-01

    This paper highlights the antagonism effect of Penicillium isolates, which were screened against the test organisms such as Staphylococcus aureus, E. coli and Penicillium sp. Penicillium notatum and Penicillium chrysogenum isolates were used for penicillin biosynthesis. The antibacterial activities of fermented crude penicillin extract were assayed by disc diffusion method. Maximum antibacterial activity was observed in Gram positive organisms (Staphylococcus aureus) when compared with Gram negative organisms. The isolated Penicillium chrysogenum can be used for large-scale penicillin antibiotic production. PMID:21117415

  15. Stochastic modelling and control of antibiotic subtilin production.

    PubMed

    Thalhofer, V; Annunziato, M; Borzì, A

    2016-09-01

    A stochastic hybrid model for the production of the antibiotic subtilin by the Bacillus subtilis is investigated. This model consists of 5 variables with four possible discrete dynamical states and this high dimensionality represents a bottleneck for using statistical tools that require to solve the corresponding Fokker-Planck problem. For this reason, a suitable reduced model with 3 variables and two dynamical states is proposed. The corresponding Fokker-Planck hyperbolic system is used to validate the evolution statistics and to construct a robust feedback control strategy to increase subtilin production. Results of numerical experiments are presented that show the effectiveness of the proposed control scheme. PMID:26837869

  16. Antibiotics.

    PubMed

    Hariprasad, Seenu M; Mieler, William F

    2016-01-01

    The Endophthalmitis Vitrectomy Study (EVS) provided ophthalmologists with evidence-based management strategies to deal with endophthalmitis for the first time. However, since the completion of the EVS, numerous unresolved issues remain. The use of oral antibiotics has important implications for the ophthalmologist, particularly in the prophylaxis and/or management of postoperative, posttraumatic, or bleb-associated bacterial endophthalmitis. One can reasonably conclude that significant intraocular penetration of an antibiotic after oral administration may be a property unique to the newer-generation fluoroquinolones. Prophylactic use of mupirocin nasal ointment resulted in significant reduction of conjunctival flora with or without preoperative topical 5% povidone-iodine preparation. Ocular fungal infections have traditionally been very difficult to treat due to limited therapeutic options both systemically and intravitreally. Because of its broad spectrum of coverage, low MIC90 levels for the organisms of concern, good tolerability, and excellent bioavailability, voriconazole through various routes of administration may be useful to the ophthalmologist in the primary treatment of or as an adjunct to the current management of ocular fungal infections. PMID:26501865

  17. Synthesis and in vitro evaluation of bisphosphonated glycopeptide prodrugs for the treatment of osteomyelitis.

    PubMed

    Tanaka, Kelly S E; Dietrich, Evelyne; Ciblat, Stéphane; Métayer, Claude; Arhin, Francis F; Sarmiento, Ingrid; Moeck, Gregory; Parr, Thomas R; Far, Adel Rafai

    2010-02-15

    As therapeutic agents of choice in the treatment of complicated infections, glycopeptide antibiotics are often preferentially used in cases of osteomyelitis, an infection located in bone and notoriously difficult to successfully manage. Yet frequent and heavy doses of these systemically administered antibiotics are conventionally prescribed to obtain higher antibiotic levels in the bone and reduce the high recurrence rates. Targeting antibiotics to the bone after systemic administration would present at least three potential advantages: (i) greater efficacy, by concentrating the therapeutic agent in bone; (ii) greater convenience, through a reduction in the frequency of administration; and (iii) greater safety, by reducing the levels of systemic drug exposure. We present here the design, synthesis and in vitro evaluation of eight prodrugs of the glycopeptide antibacterial agents vancomycin and oritavancin taking advantage of the affinity of the bisphosphonate group for bone for delivery to osseous tissues. PMID:20097069

  18. Peptidoglycan cross-linking in glycopeptide-resistant Actinomycetales.

    PubMed

    Hugonnet, Jean-Emmanuel; Haddache, Nabila; Veckerlé, Carole; Dubost, Lionel; Marie, Arul; Shikura, Noriyasu; Mainardi, Jean-Luc; Rice, Louis B; Arthur, Michel

    2014-01-01

    Synthesis of peptidoglycan precursors ending in D-lactate (D-Lac) is thought to be responsible for glycopeptide resistance in members of the order Actinomycetales that produce these drugs and in related soil bacteria. More recently, the peptidoglycan of several members of the order Actinomycetales was shown to be cross-linked by L,D-transpeptidases that use tetrapeptide acyl donors devoid of the target of glycopeptides. To evaluate the contribution of these resistance mechanisms, we have determined the peptidoglycan structure of Streptomyces coelicolor A(3)2, which harbors a vanHAX gene cluster for the production of precursors ending in D-Lac, and Nonomuraea sp. strain ATCC 39727, which is devoid of vanHAX and produces the glycopeptide A40296. Vancomycin retained residual activity against S. coelicolor A(3)2 despite efficient incorporation of D-Lac into cytoplasmic precursors. This was due to a D,D-transpeptidase-catalyzed reaction that generated a stem pentapeptide recognized by glycopeptides by the exchange of D-Lac for D-Ala and Gly. The contribution of L,D-transpeptidases to resistance was limited by the supply of tetrapeptide acyl donors, which are essential for the formation of peptidoglycan cross-links by these enzymes. In the absence of a cytoplasmic metallo-D,D-carboxypeptidase, the tetrapeptide substrate was generated by hydrolysis of the C-terminal D-Lac residue of the stem pentadepsipeptide in the periplasm in competition with the exchange reaction catalyzed by D,D-transpeptidases. In Nonomuraea sp. strain ATCC 39727, the contribution of L,D-transpeptidases to glycopeptide resistance was limited by the incomplete conversion of pentapeptides into tetrapeptides despite the production of a cytoplasmic metallo-D,D-carboxypeptidase. Since the level of drug production exceeds the level of resistance, we propose that L,D-transpeptidases merely act as a tolerance mechanism in this bacterium. PMID:24395229

  19. From Discovery to Production: Biotechnology of Marine Fungi for the Production of New Antibiotics.

    PubMed

    Silber, Johanna; Kramer, Annemarie; Labes, Antje; Tasdemir, Deniz

    2016-01-01

    Filamentous fungi are well known for their capability of producing antibiotic natural products. Recent studies have demonstrated the potential of antimicrobials with vast chemodiversity from marine fungi. Development of such natural products into lead compounds requires sustainable supply. Marine biotechnology can significantly contribute to the production of new antibiotics at various levels of the process chain including discovery, production, downstream processing, and lead development. However, the number of biotechnological processes described for large-scale production from marine fungi is far from the sum of the newly-discovered natural antibiotics. Methods and technologies applied in marine fungal biotechnology largely derive from analogous terrestrial processes and rarely reflect the specific demands of the marine fungi. The current developments in metabolic engineering and marine microbiology are not yet transferred into processes, but offer numerous options for improvement of production processes and establishment of new process chains. This review summarises the current state in biotechnological production of marine fungal antibiotics and points out the enormous potential of biotechnology in all stages of the discovery-to-development pipeline. At the same time, the literature survey reveals that more biotechnology transfer and method developments are needed for a sustainable and innovative production of marine fungal antibiotics. PMID:27455283

  20. From Discovery to Production: Biotechnology of Marine Fungi for the Production of New Antibiotics

    PubMed Central

    Silber, Johanna; Kramer, Annemarie; Labes, Antje; Tasdemir, Deniz

    2016-01-01

    Filamentous fungi are well known for their capability of producing antibiotic natural products. Recent studies have demonstrated the potential of antimicrobials with vast chemodiversity from marine fungi. Development of such natural products into lead compounds requires sustainable supply. Marine biotechnology can significantly contribute to the production of new antibiotics at various levels of the process chain including discovery, production, downstream processing, and lead development. However, the number of biotechnological processes described for large-scale production from marine fungi is far from the sum of the newly-discovered natural antibiotics. Methods and technologies applied in marine fungal biotechnology largely derive from analogous terrestrial processes and rarely reflect the specific demands of the marine fungi. The current developments in metabolic engineering and marine microbiology are not yet transferred into processes, but offer numerous options for improvement of production processes and establishment of new process chains. This review summarises the current state in biotechnological production of marine fungal antibiotics and points out the enormous potential of biotechnology in all stages of the discovery-to-development pipeline. At the same time, the literature survey reveals that more biotechnology transfer and method developments are needed for a sustainable and innovative production of marine fungal antibiotics. PMID:27455283

  1. Antibiotic Resistance

    MedlinePlus

    ... For Consumers Consumer Information by Audience For Women Antibiotic Resistance Share Tweet Linkedin Pin it More sharing options ... these products really help. To Learn More about Antibiotic Resistance Get Smart About Antibiotics (Video) Fact Sheets and ...

  2. Report: antibiotic production by thermophilic Bacillus specie SAT-4.

    PubMed

    Muhammad, Syed Aun; Ahmad, Safia; Hameed, Abdul

    2009-07-01

    Production of antimicrobial compounds seems to be a general phenomenon for most bacteria. The prevalence of antimicrobial resistance among key microbial pathogens is increasing at an alarming rate worldwide. Current solutions involve development of a more rationale approach to antibiotic use and discover of new antimicrobials. Bacillus species produce a large number of biological compounds active against bacteria, fungi, protozoa and viruses. The process of production usually involves screening of wide range of microorganisms, testing and modification. Production is carried out using fermentation. Thermophilic spore-forming, gram positive, motile rod bacterial strains were isolated from the Thar Desserts, Sindh Province, Pakistan. These strains were screened and checked for antibacterial activity. The best activity was observed by SAT4 against Micrococcus luteus, Staphylococcus aureus and Pseudomonas aeroginosa. The activity was only observed against gram positive bacteria and no activity was seen against Pseudomonas aeroginosa. Thermophilic Bacillus specie SAT4 was found to be active in the fermentation process to produce the antimicrobial agents. Further optimizations of different conditions (time of incubation, media, pH, glucose concentrations, nitrogen concentrations, and temperature) for antimicrobial production by the selected bacterial strain was performed. Agar diffusion assay was performed to evaluate the antibacterial activity. Optimum conditions for the production of antimicrobials by selected isolate were observed to be 48 hour, pH 5, temperature 55 degrees C, 2% glucose and 1.5% nitrogen concentration. This newly isolated bacterial strain has great potential for antimicrobial production at industrial scale. PMID:19553186

  3. Presence and biological activity of antibiotics used in fuel ethanol and corn co-product production.

    PubMed

    Compart, D M Paulus; Carlson, A M; Crawford, G I; Fink, R C; Diez-Gonzalez, F; Dicostanzo, A; Shurson, G C

    2013-05-01

    Antibiotics are used in ethanol production to control bacteria from competing with yeast for nutrients during starch fermentation. However, there is no published scientific information on whether antibiotic residues are present in distillers grains (DG), co-products from ethanol production, or whether they retain their biological activity. Therefore, the objectives of this study were to quantify concentrations of various antibiotic residues in DG and determine whether residues were biologically active. Twenty distillers wet grains and 20 distillers dried grains samples were collected quarterly from 9 states and 43 ethanol plants in the United States. Samples were analyzed for DM, CP, NDF, crude fat, S, P, and pH to describe the nutritional characteristics of the samples evaluated. Samples were also analyzed for the presence of erythromycin, penicillin G, tetracycline, tylosin, and virginiamycin M1, using liquid chromatography and mass spectrometry. Additionally, virginiamycin residues were determined, using a U.S. Food and Drug Administration-approved bioassay method. Samples were extracted and further analyzed for biological activity by exposing the sample extracts to 10(4) to 10(7) CFU/mL concentrations of sentinel bacterial strains Escherichia coli ATCC 8739 and Listeria monocytogenes ATCC 19115. Extracts that inhibited bacterial growth were considered to have biological activity. Physiochemical characteristics varied among samples but were consistent with previous findings. Thirteen percent of all samples contained low (≤1.12 mg/kg) antibiotic concentrations. Only 1 sample extract inhibited growth of Escherichia coli at 10(4) CFU/mL, but this sample contained no detectable concentrations of antibiotic residues. No extracts inhibited Listeria monocytogenes growth. These data indicate that the likelihood of detectable concentrations of antibiotic residues in DG is low; and if detected, they are found in very low concentrations. The inhibition in only 1 DG

  4. [Influence of personal attitude of the manager on antibiotic use in pig production].

    PubMed

    Malik, J; Kaufmann, G; Hirsiger, P; Kümmerlen, D; Arnold, C; Spring, P; Sidler, X

    2015-12-01

    The attitude as well as the expertise of a person affect the behavior and actions in daily life. To investigate the influence of attitude and knowledge of pig producers on the use of antibiotics in farms, 220 Swiss pig producers were questioned on health awareness, attitude towards sustainable production, risk behavior, intrinsic motivation and knowledge about antibiotics and resistance development. In addition, the strategy of antibiotic use (therapeutic or prophylactic) and the business practice (single or group therapy) for the amount of antibiotics on one hand and for the risk of antibiotic resistance development on the other hand, were determined in a personal interview. Farmers using antibiotics only therapeutically had a better business practice. A direct link between the personal attitude and the antibiotic use or a higher risk of development of antibiotic resistance was not found in this investigation. PMID:26891573

  5. 21 CFR 333.150 - Labeling of first aid antibiotic drug products.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 5 2014-04-01 2014-04-01 false Labeling of first aid antibiotic drug products. 333.150 Section 333.150 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE TOPICAL ANTIMICROBIAL DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE First Aid Antibiotic Drug Products §...

  6. A Transposon Screen Identifies Genetic Determinants of Vibrio cholerae Resistance to High-Molecular-Weight Antibiotics.

    PubMed

    Dörr, Tobias; Delgado, Fernanda; Umans, Benjamin D; Gerding, Matthew A; Davis, Brigid M; Waldor, Matthew K

    2016-08-01

    Gram-negative bacteria are notoriously resistant to a variety of high-molecular-weight antibiotics due to the limited permeability of their outer membrane (OM). The basis of OM barrier function and the genetic factors required for its maintenance remain incompletely understood. Here, we employed transposon insertion sequencing to identify genes required for Vibrio cholerae resistance to vancomycin and bacitracin, antibiotics that are thought to be too large to efficiently penetrate the OM. The screen yielded several genes whose protein products are predicted to participate in processes important for OM barrier functions and for biofilm formation. In addition, we identified a novel factor, designated vigA (for vancomycin inhibits growth), that has not previously been characterized or linked to outer membrane function. The vigA open reading frame (ORF) codes for an inner membrane protein, and in its absence, cells became highly sensitive to glycopeptide antibiotics (vancomycin and ramoplanin) and bacitracin but not to other large antibiotics or detergents. In contrast to wild-type (WT) cells, the vigA mutant was stained with fluorescent vancomycin. These observations suggest that VigA specifically prevents the periplasmic accumulation of certain large antibiotics without exerting a general role in the maintenance of OM integrity. We also observed marked interspecies variability in the susceptibilities of Gram-negative pathogens to glycopeptides and bacitracin. Collectively, our findings suggest that the OM barrier is not absolute but rather depends on specific OM-antibiotic interactions. PMID:27216069

  7. Mobile antibiotic resistance - the spread of genes determining the resistance of bacteria through food products.

    PubMed

    Godziszewska, Jolanta; Guzek, Dominika; Głąbski, Krzysztof; Wierzbicka, Agnieszka

    2016-01-01

    In recent years, more and more antibiotics have become ineffective in the treatment of bacterial nfections. The acquisition of antibiotic resistance by bacteria is associated with circulation of genes in the environment. Determinants of antibiotic resistance may be transferred to pathogenic bacteria. It has been shown that conjugation is one of the key mechanisms responsible for spread of antibiotic resistance genes, which is highly efficient and allows the barrier to restrictions and modifications to be avoided. Some conjugative modules enable the transfer of plasmids even between phylogenetically distant bacterial species. Many scientific reports indicate that food is one of the main reservoirs of these genes. Antibiotic resistance genes have been identified in meat products, milk, fruits and vegetables. The reason for such a wide spread of antibiotic resistance genes is the overuse of antibiotics by breeders of plants and animals, as well as by horizontal gene transfer. It was shown, that resistance determinants located on mobile genetic elements, which are isolated from food products, can easily be transferred to another niche. The antibiotic resistance genes have been in the environment for 30 000 years. Their removal from food products is not possible, but the risks associated with the emergence of multiresistant pathogenic strains are very large. The only option is to control the emergence, selection and spread of these genes. Therefore measures are sought to prevent horizontal transfer of genes. Promising concepts involve the combination of developmental biology, evolution and ecology in the fight against the spread of antibiotic resistance. PMID:27383577

  8. Use of 'natural' products as alternatives to antibiotic feed additives in ruminant production.

    PubMed

    Jouany, J-P; Morgavi, D P

    2007-11-01

    The banning in 2006 of the use of antibiotics as animal growth promoters in the European Union has increased demand from producers for alternative feed additives that can be used to improve animal production. This review gives an overview of the most common non-antibiotic feed additives already being used or that could potentially be used in ruminant nutrition. Probiotics, dicarboxylic acids, enzymes and plant-derived products including saponins, tannins and essential oils are presented. The known modes of action and effects of these additives on feed digestion and more especially on rumen fermentations are described. Their utility and limitations in field conditions for modern ruminant production systems and their compliance with the current legislation are also discussed. PMID:22444918

  9. Alternative Pathway to a Glycopeptide-Resistant Cell Wall in the Balhimycin Producer Amycolatopsis balhimycina.

    PubMed

    Frasch, Hans-Joerg; Kalan, Lindsay; Kilian, Regina; Martin, Tobias; Wright, Gerard D; Stegmann, Evi

    2015-06-12

    Balhimycin, a vancomycin-type glycopeptide, is a lipid II targeting antibiotic produced by Amycolatopsis balhimycina. A. balhimycina has developed a self-resistance mechanism based on the synergistic action of different enzymes resulting in modified peptidoglycan. The canonical resistance mechanism against glycopeptides is the synthesis of peptidoglycan precursors ending with acyl-d-alanyl-d-lactate (d-Ala-d-Lac) rather than acyl-d-alanyl-d-alanine (d-Ala-d-Ala). This reprogramming is the result of the enzymes VanH, VanA, and VanX. VanH and VanA are required to produce d-Ala-d-Lac; VanX cleaves cytosolic pools of d-Ala-d-Ala, thereby ensuring that peptidoglycan is enriched in d-Ala-d-Lac. In A. balhimycina, the ΔvanHAXAb mutant showed a reduced glycopeptide resistance in comparison to the wild type. Nevertheless, ΔvanHAXAb was paradoxically still able to produce d-Ala-d-Lac containing resistant cell wall precursors suggesting the presence of a novel alternative glycopeptide resistance mechanism. In silico analysis, inactivation studies, and biochemical assays led to the characterization of an enzyme, Ddl1Ab, as a paraloguous chromosomal d-Ala-d-Lac ligase able to complement the function of VanAAb in the ΔvanHAXAb mutant. Furthermore, A. balhimycina harbors a vanYAb gene encoding a d,d-carboxypeptidase. Transcriptional analysis revealed an upregulated expression of vanYAb in the ΔvanHAXAb mutant. VanYAb cleaves the endstanding d-Ala from the pentapeptide precursors, reducing the quantity of sensitive cell wall precursors in the absence of VanXAb. These findings represent an unprecedented coordinated layer of resistance mechanisms in a glycopeptide antibiotic producing bacterium. PMID:27622740

  10. Evaluation of residual antibacterial potency in antibiotic production wastewater using a real-time quantitative method.

    PubMed

    Zhang, Hong; Zhang, Yu; Yang, Min; Liu, Miaomiao

    2015-11-01

    While antibiotic pollution has attracted considerable attention due to its potential in promoting the dissemination of antibiotic resistance genes in the environment, the antibiotic activity of their related substances has been neglected, which may underestimate the environmental impacts of antibiotic wastewater discharge. In this study, a real-time quantitative approach was established to evaluate the residual antibacterial potency of antibiotics and related substances in antibiotic production wastewater (APW) by comparing the growth of a standard bacterial strain (Staphylococcus aureus) in tested water samples with a standard reference substance (e.g. oxytetracycline). Antibiotic equivalent quantity (EQ) was used to express antibacterial potency, which made it possible to assess the contribution of each compound to the antibiotic activity in APW. The real-time quantitative method showed better repeatability (Relative Standard Deviation, RSD 1.08%) compared with the conventional fixed growth time method (RSD 5.62-11.29%). And its quantification limits ranged from 0.20 to 24.00 μg L(-1), depending on the antibiotic. We applied the developed method to analyze the residual potency of water samples from four APW treatment systems, and confirmed a significant contribution from antibiotic transformation products to potent antibacterial activity. Specifically, neospiramycin, a major transformation product of spiramycin, was found to contribute 13.15-22.89% of residual potency in spiramycin production wastewater. In addition, some unknown related substances with antimicrobial activity were indicated in the effluent. This developed approach will be effective for the management of antibacterial potency discharge from antibiotic wastewater and other waste streams. PMID:26395288

  11. Antibiotic resistance—consequences for animal health, welfare, and food production

    PubMed Central

    Bengtsson, Björn

    2014-01-01

    Most of the literature on the consequences of emergence and spread of bacteria resistant to antibiotics among animals relate to the potential impact on public health. But antibiotics are used to treat sick animals, and resistance in animal pathogens may lead to therapy failure. This has received little scientific attention, and therefore, in this article, we discuss examples that illustrate the possible impact of resistance on animal health and consequences thereof. For all animals, there may be a negative effect on health and welfare when diseases cannot be treated. Other consequences will vary depending on why and how different animal species are kept. Animals kept as companions or for sports often receive advanced care, and antibiotic resistance can lead to negative social and economic consequences for the owners. Further, spread of hospital-acquired infections can have an economic impact on the affected premises. As to animals kept for food production, antibiotics are not needed to promote growth, but, if infectious diseases cannot be treated when they occur, this can have a negative effect on the productivity and economy of affected businesses. Antibiotic resistance in animal bacteria can also have positive consequences by creating incentives for adoption of alternative regimes for treatment and prevention. It is probable that new antibiotic classes placed on the market in the future will not reach veterinary medicine, which further emphasizes the need to preserve the efficacy of currently available antibiotics through antibiotic stewardship. A cornerstone in this work is prevention, as healthy animals do not need antibiotics. PMID:24678738

  12. Termite usage associated with antibiotic therapy: enhancement of aminoglycoside antibiotic activity by natural products of Nasutitermes corniger (Motschulsky 1855)

    PubMed Central

    Coutinho, Henrique DM; Vasconcellos, Alexandre; Lima, Micheline A; Almeida-Filho, Geraldo G; Alves, Rômulo RN

    2009-01-01

    Background Several species from Insecta are used as remedies. Among these species, the termite Nasutitermes corniger is commonly used in traditional medicine in Northeast Brazil. The present work tests the modifying antibiotic activity of Nasutitermes corniger, a termite used in folk medicine in Northeastern region of Brazil. Methods Chlorpromazine and decocts of N. corniger were collected from two different plant species used in the traditional medicine were tested for their antimicrobial activity against strains of Escherichia coli resistant to aminoglycosides. The growth of two bacterial strains of E. coli was tested using decocts and chlorpromazine alone or associeted with aminogycosides. Results The MIC and MBC values were ≥1024 μg/ml for both strains of E. coli assayed. A significant synergism was observed between both decocts and chlorpromazine when assyed with neomycin. This synergism with neomycin indicates the involvement of an efflux system in the resistance to this aminoglycoside. Conclusion Therefore it is suggested that natural products from N. corniger could be used as a source of zoo-derived natural products with modifying antibiotic activity to aminoglycosides, being a new weapon against the bacterial resistance to antibiotics. PMID:19761599

  13. Antibiotics production by an actinomycete isolated from the termite gut.

    PubMed

    Matsui, Toru; Tanaka, Junichi; Namihira, Tomoyuki; Shinzato, Naoya

    2012-12-01

    As well as the search for new antibiotics, a new resource or strains for the known antibiotics is also important. Microbial symbionts in the gut of termites could be regarded as one of the feasible resource for such purpose. In this study, antibiotic-producing actinomycetes were screened from symbionts of the termite gut. 16SrRNA sequence analysis for the 10 isolates revealed that they belong to actinomycetes such as Streptomyces sp., Kitasatospora sp., and Mycobacterium sp. A culture broth from one of the isolate, namely strain CA1, belonging to the genera Streptomyces exhibited antagonistic activity against actinomycetes (Micrococcus spp.), gram-positive bacteria (Bacillus spp.), and yeast (Candida spp.). The structures of 2 compounds isolated from the culture broth of the strain CA1 were identified as those of actinomycin X2 and its analog, D. This study is the first to report that some symbionts of the termite gut are antibiotic-producing actinomycetes, and suggest that the termite gut is a feasible resource for bioprospecting. PMID:22359219

  14. The transport of antibiotic resistance genes and residues in groundwater near swine production facilities

    NASA Astrophysics Data System (ADS)

    Lin, Y. F.; Yannarell, A. C.; Mackie, R. I.; Krapac, I. G.; Chee-Sanford, J. S.; Koike, S.

    2008-12-01

    The use of antibiotics at concentrated animal feeding operations (CAFOs) for disease prevention, disease treatment, and growth promotion can contribute to the spread of antibiotic compounds, their breakdown products, and antibiotic resistant bacteria and/or the genes that confer resistance. In addition, constitutive use of antibiotics at sub-therapeutic levels can select for antibiotic resistance among the bacteria that inhabit animal intestinal tracts, onsite manure treatment facilities, and any environments receiving significant inputs of manure (e.g. through waste lagoon leakage or fertilizer amendments to farm soils). If the antibiotic resistant organisms persist in these new environments, or if they participate in genetic exchanges with the native microflora, then CAFOs may constitute a significant reservoir for the spread of antibiotic resistance to the environment at large. Our results have demonstrated that leakage from waste treatment lagoons can influence the presence and persistence of tetracycline resistance genes in the shallow aquifer adjacent to swine CAFOs, and molecular phylogeny allowed us to distinguish "native" tetracycline resistance genes in control groundwater wells from manure-associated genes introduced from the lagoon. We have also been able to detect the presence of erythromycin resistance genes in CAFO surface and groundwater even though erythromycin is strictly reserved for use in humans and thus is not utilized at any of these sites. Ongoing research, including modeling of particle transport in groundwater, will help to determine the potential spatial and temporal extent of CAFO-derived antibiotic resistance.

  15. N-Glycopeptide Profiling in Arabidopsis Inflorescence.

    PubMed

    Xu, Shou-Ling; Medzihradszky, Katalin F; Wang, Zhi-Yong; Burlingame, Alma L; Chalkley, Robert J

    2016-06-01

    This study presents the first large-scale analysis of plant intact glycopeptides. Using wheat germ agglutinin lectin weak affinity chromatography to enrich modified peptides, followed by electron transfer dissociation (ETD)(1) fragmentation tandem mass spectrometry, glycan compositions on over 1100 glycopeptides from 270 proteins found in Arabidopsis inflorescence tissue were characterized. While some sites were only detected with a single glycan attached, others displayed up to 16 different glycoforms. Among the identified glycopeptides were four modified in nonconsensus glycosylation motifs. While most of the modified proteins are secreted, membrane, endoplasmic reticulum (ER), or Golgi-localized proteins, surprisingly, N-linked sugars were detected on a protein predicted to be cytosolic or nuclear. PMID:27067053

  16. Unusual Fragmentation Pathways in Collagen Glycopeptides

    NASA Astrophysics Data System (ADS)

    Perdivara, Irina; Perera, Lalith; Sricholpech, Marnisa; Terajima, Masahiko; Pleshko, Nancy; Yamauchi, Mitsuo; Tomer, Kenneth B.

    2013-07-01

    Collagens are the most abundant glycoproteins in the body. One characteristic of this protein family is that the amino acid sequence consists of repeats of three amino acids -(X—Y—Gly)n. Within this motif, the Y residue is often 4-hydroxyproline (HyP) or 5-hydroxylysine (HyK). Glycosylation in collagen occurs at the 5-OH group in HyK in the form of two glycosides, galactosylhydroxylysine (Gal-HyK) and glucosyl galactosylhydroxylysine (GlcGal-HyK). In collision induced dissociation (CID), collagen tryptic glycopeptides exhibit unexpected gas-phase dissociation behavior compared to typical N- and O-linked glycopeptides (i.e., in addition to glycosidic bond cleavages, extensive cleavages of the amide bonds are observed). The Gal- or GlcGal- glycan modifications are largely retained on the fragment ions. These features enable unambiguous determination of the amino acid sequence of collagen glycopeptides and the location of the glycosylation site. This dissociation pattern was consistent for all analyzed collagen glycopeptides, regardless of their length or amino acid composition, collagen type or tissue. The two fragmentation pathways—amide bond and glycosidic bond cleavage—are highly competitive in collagen tryptic glycopeptides. The number of ionizing protons relative to the number of basic sites (i.e., Arg, Lys, HyK, and N-terminus) is a major driving force of the fragmentation. We present here our experimental results and employ quantum mechanics calculations to understand the factors enhancing the labile character of the amide bonds and the stability of hydroxylysine glycosides in gas phase dissociation of collagen glycopeptides.

  17. Novel Two-Component Systems Implied in Antibiotic Production in Streptomyces coelicolor

    PubMed Central

    Yepes, Ana; Rico, Sergio; Rodríguez-García, Antonio; Santamaría, Ramón I.; Díaz, Margarita

    2011-01-01

    The abundance of two-component systems (TCSs) in Streptomyces coelicolor A3(2) genome indicates their importance in the physiology of this soil bacteria. Currently, several TCSs have been related to antibiotic regulation, and the purpose in this study was the characterization of five TCSs, selected by sequence homology with the well-known absA1A2 system, that could also be associated with this important process. Null mutants of the five TCSs were obtained and two mutants (ΔSCO1744/1745 and ΔSCO4596/4597/4598) showed significant differences in both antibiotic production and morphological differentiation, and have been renamed as abr (antibiotic regulator). No detectable changes in antibiotic production were found in the mutants in the systems that include the ORFs SCO3638/3639, SCO3640/3641 and SCO2165/2166 in any of the culture conditions assayed. The system SCO1744/1745 (AbrA1/A2) was involved in negative regulation of antibiotic production, and acted also as a negative regulator of the morphological differentiation. By contrast, the system SCO4596/4597/4598 (AbrC1/C2/C3), composed of two histidine kinases and one response regulator, had positive effects on both morphological development and antibiotic production. Microarray analyses of the ΔabrC1/C2/C3 and wild-type transcriptomes revealed downregulation of actII-ORF4 and cdaR genes, the actinorhodin and calcium-dependent antibiotic pathway-specific regulators respectively. These results demonstrated the involvement of these new two-component systems in antibiotic production and morphological differentiation by different approaches. One is a pleiotropic negative regulator: abrA1/A2. The other one is a positive regulator composed of three elements, two histidine kinases and one response regulator: abrC1/C2/C3. PMID:21625497

  18. YS-822A, a new polyene macrolide antibiotic. I. Production, isolation, characterization and biological properties.

    PubMed

    Itoh, A; Ido, J; Iwamoto, Y; Goshima, E; Miki, T; Hasuda, K; Hirota, H

    1990-08-01

    A new polyene macrolide antibiotic, YS-822A was isolated from the culture filtrate of a mutant strain H-8 of Streptoverticillium eurocidicum var. asterocidicus S-822. Whereas the original S-822 strain produced not only YS-822 substances but also teleocidin as by-product which is well-known as a strong carcinogenic promoter, the mutagenized H-8 strain produced the antibiotic with only a trace amount of teleocidin. Chemical and biological characterizations of the antibiotic revealed that YS-822A (molecular formula: C37H59NO14) is a new polyene macrolide with a wide antifungal spectrum and a low acute toxicity. PMID:2211361

  19. Characterization of immunomodulatory activities of honey glycoproteins and glycopeptides.

    PubMed

    Mesaik, M Ahmed; Dastagir, Nida; Uddin, Nazim; Rehman, Khalid; Azim, M Kamran

    2015-01-14

    Recent evidence suggests an important role for natural honey in modulating immune response. To identify active components responsible, this study investigated the immunomodulatory properties of glycoproteins and glycopeptides fractionated from Ziziphus honey. Honey proteins/peptides were fractionated by size exclusion chromatography into five peaks with molecular masses in the range of 2-450 kDa. The fractionated proteins exhibited potent, concentration-dependent inhibition of reactive oxygen species production in zymosan-activated human neutrophils (IC50 = 6-14 ng/mL) and murine macrophages (IC50 = 2-9 ng/mL). Honey proteins significantly suppressed the nitric oxide production by LPS-activated murine macrophages (IC50 = 96-450 ng/mL). Moreover, honey proteins inhibited the phagocytosis latex bead macrophages. The production of pro-inflammatory cytokines IL-1β and TNF-α by human monocytic cell line in the presence of honey proteins was analyzed. Honey proteins did not affect the production of IL-1β; however, TNF-α production was significantly suppressed. These findings indicated that honey glycoproteins and glycopeptides significantly interfere with molecules of the innate immune system. PMID:25496517

  20. Occurrence of antibiotics and their impacts to primary productivity in fishponds around Tai Lake, China.

    PubMed

    Song, Chao; Zhang, Cong; Fan, Limin; Qiu, Liping; Wu, Wei; Meng, Shunlong; Hu, Gengdong; Kamira, Barry; Chen, Jiazhang

    2016-10-01

    Antibiotics are widely used to improve the health and yields of farmed animals, including fish, but their use is accompanied by undesirable ecological effects. Relatively little is known about the water-body burden of antibiotics and their influence on primary productivity in aquaculture ecosystem. In this study, antibiotics usage within 24 fishponds, covering 4 areas, sampled 5 times, and having 5 fish species, was investigated surrounding Tai Lake in China. The study analyzed 15 antibiotics (including 5 sulfonamides, 2 quinolones, 3 β-lactams, 3 tetracyclines, 1 amphenicol, and 1 macrolide), and all of them were detected in water samples, with a detection frequency of 2-60%. Sulfonamides were the most prevalent, and concentrations of sulfamethoxazole, sulfamonomethoxine, and florfenicol being over 2000 ng L(-1) in some samples, while the other antibiotics levels ranged from ND (no detection) to 551.18 ng L(-1). Significant differences were observed in antibiotic burden among different regions for total antibiotics, sulfonamides, quinolones, and amphenicols; among time points for quinolones, β-lactams, and tetracyclines; and among species for quinolones and macrolides. Furthermore, basing on the risk quotient (RQ) method, the assessment revealed that florfenicol was of highest risk to algae with RQ values exceeding 0.1, while macrolide erythromycin posed the second highest risk. The partial correlation coefficient between total antibiotics and chlorophyll (a) was -0.035 that clearly indicated total antibiotics were detrimental to green algae growth, while the nutrient input and other physical - chemical factors were much more beneficial. Overall, holistic far-reaching measures of antibiotics control are recommended to preserve aquaculture ecosystem health. PMID:27424054

  1. Monitoring of Antibiotic Residues in Aquatic Products in Urban and Rural Areas of Vietnam.

    PubMed

    Uchida, Kotaro; Konishi, Yoshimasa; Harada, Kazuo; Okihashi, Masahiro; Yamaguchi, Takahiro; Do, Mai Hoang Ngoc; Thi Bui, Long; Duc Nguyen, Thinh; Do Nguyen, Phuc; Thi Khong, Diep; Thi Tran, Hoa; Nam Nguyen, Thang; Viet Le, Ha; Van Chau, Vien; Thi Van Dao, Khanh; Thi Ngoc Nguyen, Hue; Kajimura, Keiji; Kumeda, Yuko; Tran Pham, Khanh; Ngoc Pham, Khai; Trong Bui, Chien; Quang Vien, Mai; Hoang Le, Ninh; Van Dang, Chinh; Hirata, Kazumasa; Yamamoto, Yoshimasa

    2016-08-10

    Antibiotic residues in aquatic products in Vietnam were investigated. A total of 511 fish and shrimp samples were collected from markets in Ho Chi Minh City (HCMC), Thai Binh (TB), and Nha Trang (NT) from July 2013 to October 2015. The samples were extracted with 2% formic acid in acetonitrile and washed with dispersive C18 sorbent. Thirty-two antibiotics were analyzed by LC-MS/MS. Of the 362 samples from HCMC, antibiotic residues were found in 53 samples. Enrofloxacin was commonly detected, at a rate of 10.8%. In contrast, samples from TB and NT were less contaminated: only 1 of 118 analyzed samples showed residues in TB and only 1 of 31 showed residues in NT. These differences were attributed to the local manufacturing/distribution systems. To understand the current status of antibiotic use and prevent adverse effects that may be caused by their overuse, continual monitoring is required. PMID:27160655

  2. Identification and manipulation of the pleuromutilin gene cluster from Clitopilus passeckerianus for increased rapid antibiotic production

    NASA Astrophysics Data System (ADS)

    Bailey, Andy M.; Alberti, Fabrizio; Kilaru, Sreedhar; Collins, Catherine M.; de Mattos-Shipley, Kate; Hartley, Amanda J.; Hayes, Patrick; Griffin, Alison; Lazarus, Colin M.; Cox, Russell J.; Willis, Christine L.; O’Dwyer, Karen; Spence, David W.; Foster, Gary D.

    2016-05-01

    Semi-synthetic derivatives of the tricyclic diterpene antibiotic pleuromutilin from the basidiomycete Clitopilus passeckerianus are important in combatting bacterial infections in human and veterinary medicine. These compounds belong to the only new class of antibiotics for human applications, with novel mode of action and lack of cross-resistance, representing a class with great potential. Basidiomycete fungi, being dikaryotic, are not generally amenable to strain improvement. We report identification of the seven-gene pleuromutilin gene cluster and verify that using various targeted approaches aimed at increasing antibiotic production in C. passeckerianus, no improvement in yield was achieved. The seven-gene pleuromutilin cluster was reconstructed within Aspergillus oryzae giving production of pleuromutilin in an ascomycete, with a significant increase (2106%) in production. This is the first gene cluster from a basidiomycete to be successfully expressed in an ascomycete, and paves the way for the exploitation of a metabolically rich but traditionally overlooked group of fungi.

  3. Identification and manipulation of the pleuromutilin gene cluster from Clitopilus passeckerianus for increased rapid antibiotic production

    PubMed Central

    Bailey, Andy M.; Alberti, Fabrizio; Kilaru, Sreedhar; Collins, Catherine M.; de Mattos-Shipley, Kate; Hartley, Amanda J.; Hayes, Patrick; Griffin, Alison; Lazarus, Colin M.; Cox, Russell J.; Willis, Christine L.; O’Dwyer, Karen; Spence, David W.; Foster, Gary D.

    2016-01-01

    Semi-synthetic derivatives of the tricyclic diterpene antibiotic pleuromutilin from the basidiomycete Clitopilus passeckerianus are important in combatting bacterial infections in human and veterinary medicine. These compounds belong to the only new class of antibiotics for human applications, with novel mode of action and lack of cross-resistance, representing a class with great potential. Basidiomycete fungi, being dikaryotic, are not generally amenable to strain improvement. We report identification of the seven-gene pleuromutilin gene cluster and verify that using various targeted approaches aimed at increasing antibiotic production in C. passeckerianus, no improvement in yield was achieved. The seven-gene pleuromutilin cluster was reconstructed within Aspergillus oryzae giving production of pleuromutilin in an ascomycete, with a significant increase (2106%) in production. This is the first gene cluster from a basidiomycete to be successfully expressed in an ascomycete, and paves the way for the exploitation of a metabolically rich but traditionally overlooked group of fungi. PMID:27143514

  4. [Use of hydrogen peroxide in the treatment of sewage in antibiotic production].

    PubMed

    Polunina, E E; Zav'ialova, E V; Shchipanov, N P; Savina, N N

    1996-03-01

    The possible use of hydrogen peroxide as an oxidant in the local treatment of the sewage in antibiotic production was investigated. The data on oxidation of SASs and other pollutants in antibiotic production by hydrogen peroxide alone or in the presence of ferrous sulfate as a homogenous catalyst are presented. The influence of the sewage preliminary treatment by hydrogen peroxide on the foaming was studied. It was shown advisable to use the described process for the local treatment as the first stage followed by the sewage electrochemical treatment. PMID:8967796

  5. Prevalence of Veterinary Antibiotics and Antibiotic-Resistant Escherichia coli in the Surface Water of a Livestock Production Region in Northern China

    PubMed Central

    Zhang, Xuelian; Li, Yanxia; Liu, Bei; Wang, Jing; Feng, Chenghong; Gao, Min; Wang, Lina

    2014-01-01

    This study investigated the occurrence of 12 veterinary antibiotics (VAs) and the susceptibility of Escherichia coli (E. coli) in a rural water system that was affected by livestock production in northern China. Each of the surveyed sites was determined with at least eight antibiotics with maximum concentration of up to 450 ng L−1. The use of VAs in livestock farming probably was a primary source of antibiotics in the rivers. Increasing total antibiotics were measured from up- to mid- and downstream in the two tributaries. Eighty-eight percent of the 218 E. coli isolates that were derived from the study area exhibited, in total, 48 resistance profiles against the eight examined drugs. Significant correlations were found among the resistance rates of sulfamethoxazole-trimethoprim, chloromycetin and ampicillin as well as between tetracycline and chlortetracycline, suggesting a possible cross-selection for resistance among these drugs. The E. coli resistance frequency also increased from up- to midstream in the three rivers. E. coli isolates from different water systems showed varying drug numbers of resistance. No clear relationship was observed in the antibiotic resistance frequency with corresponding antibiotic concentration, indicating that the antibiotic resistance for E. coli in the aquatic environment might be affected by factors besides antibiotics. High numbers of resistant E. coli were also isolated from the conserved reservoir. These results suggest that rural surface water may become a large pool of VAs and resistant bacteria. This study contributes to current information on VAs and resistant bacteria contamination in aquatic environments particularly in areas under intensive agriculture. Moreover, this study indicates an urgent need to monitor the use of VAs in animal production, and to control the release of animal-originated antibiotics into the environment. PMID:25372873

  6. Detection and Characterization of Low Abundance Glycopeptides Via Higher-Energy C-Trap Dissociation and Orbitrap Mass Analysis

    NASA Astrophysics Data System (ADS)

    Hart-Smith, Gene; Raftery, Mark J.

    2012-01-01

    Broad-scale mass spectrometric analyses of glycopeptides are constrained by the considerable complexity inherent to glycoproteomics, and techniques are still being actively developed to address the associated analytical difficulties. Here we apply Orbitrap mass analysis and higher-energy C-trap dissociation (HCD) to facilitate detailed insights into the compositions and heterogeneity of complex mixtures of low abundance glycopeptides. By generating diagnostic oxonium product ions at mass measurement errors of <5 ppm, highly selective glycopeptide precursor ion detections are made at sub-fmol limits of detection: analyses of proteolytic digests of a hen egg glycoprotein mixture detect 88 previously uncharacterized glycopeptides from 666 precursor ions selected for MS/MS, with only one false positive due to co-fragmentation of a non-glycosylated peptide with a glycopeptide. We also demonstrate that by (1) identifying multiple series of glycoforms using high mass accuracy single stage MS spectra, and (2) performing product ion scans at optimized HCD collision energies, the identification of peptide + N-acetylhexosamine (HexNAc) ions (Y1 ions) can be readily achieved at <5 ppm mass measurement errors. These data allow base peptide sequences and glycan compositional information to be attained with high confidence, even for glycopeptides that produce weak precursor ion signals and/or low quality MS/MS spectra. The glycopeptides characterized from low fmol abundances using these methods allow two previously unreported glycosylation sites on the Gallus gallus protein ovoglycoprotein (amino acids 82 and 90) to be confirmed; considerable glycan heterogeneities at amino acid 90 of ovoglycoprotein, and amino acids 34 and 77 of Gallus gallus ovomucoid are also revealed.

  7. ARS Research Review on "Recent progress in developing alternative strategies to antibiotics in poultry production"

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The global animal industry needs to address the increasing regulatory restrictions on the use of antibiotic growth promoters (AGPs) in animal production. Many AGPs have already been restricted by animal farms in the European Union and soon other countries are expected to be under increasing scrutin...

  8. Targeted delivery of DNA using YEE(GalNAcAH)3, a synthetic glycopeptide ligand for the asialoglycoprotein receptor.

    PubMed

    Merwin, J R; Noell, G S; Thomas, W L; Chiou, H C; DeRome, M E; McKee, T D; Spitalny, G L; Findeis, M A

    1994-01-01

    In vivo gene therapy shows promise as a treatment for both genetic and acquired disorders. The hepatic asialoglycoprotein receptor (ASGPr) binds asialoorosomucoid-polylysine-DNA (ASOR-PL-DNA) complexes and allows targeted delivery to hepatocytes. The tris(N-acetylgalactosamine aminohexyl glycoside) amide of tyrosyl(glutamyl) glutamate [YEE(GalNAcAH)3] has been previously reported to have subnanomolar affinity for the ASGPr. We have used an iodinated derivative of YEE(GalNAcAH)3 linked to polylysine and complexed to the luciferase gene (pCMV-Luc) in receptor-binding experiments to establish the feasibility of substituting ASOR with the synthetic glycopeptide for gene therapy. Scatchard analyses revealed similar Kd values for both ASOR and the glycopeptide. Binding and internalization of 125I-Suc-YEE(GalNAcAH)3 were competitively inhibited with either unlabeled ASOR or glycopeptide. The reverse was also true; 125I-ASOR binding was competed with unlabeled YEE(GalNAcAH)3 suggesting specific binding to the ASGPr by both compounds. Examination of in vivo delivery revealed that the 125I-labeled glycopeptide complex mimicked previous results observed with 125I-ASOR-PL-DNA. CPM in the liver accounted for 96% of the radioactivity recovered from the five major organs (liver, spleen, kidney, heart, and lungs). Cryoautoradiography displayed iodinated glycopeptide complex bound preferentially to hepatocytes rather than nonparenchymal cells. In vitro, as well as in vivo, transfections using the glycopeptide-polylysine-pCMV-luciferase gene complex (YG3-PL-Luc) resulted in expression of the gene product. These data demonstrate that the YEE(GalNAcAH)3 synthetic glycopeptide can be used as a ligand in targeted delivery of DNA to the liver-specific ASGPr. PMID:7873664

  9. Biomedicine of Enkephalin-Derived Glycopeptide Analgesics

    NASA Astrophysics Data System (ADS)

    Polt, Robin

    The incorporation of glycosides into peptide neurotransmitters imparts drug-like character to the neurotransmitter "message" via "membrane hopping". The importance of the glycopeptide-membrane interaction is emphasized, and the biousian theory is briefly explained. Application of this approach to enkephalins, the endogenous opioid peptides, leads to potent analgesic compounds capable of systemic delivery. The clinical applications of these compounds are advocated by the author.

  10. Antibiotics and bioactive natural products in treatment of methicillin resistant Staphylococcus aureus: A brief review

    PubMed Central

    Kali, Arunava

    2015-01-01

    Infections caused by Staphylococcus aureus strains with Methicillin resistance are associated with increased mortality and morbidity, aggressive course, multiple drug resistance and hospital outbreaks. Several first and second line antibiotics are rapidly becoming ineffective for treatment due to emergence of resistance. Extracts of medicinal plants are rich source of unique phytochemicals. Plants used in traditional medicine have been reported to have significant anti-MRSA activity. The objective of this review is to provide a brief overview of antibiotics as well as anti-MRSA natural products and their future prospect. PMID:26009690

  11. Cold drugs. Circulation, production and intelligence of antibiotics in post-WWII years.

    PubMed

    Capocci, Mauro

    2014-01-01

    The paper details how the earliest antibiotics were subject to a strict control during the earliest phase of the Cold War. Because of antibiotics strategic and economic value, Anglo-American Governments restricted circulation of scientists, techno-scientific know-how and technology related to penicillin production, as well as closely controlling the circulation of the drugs in the Communist countries. These efforts are documented by archival documents, testifying how drugs were actual instruments of propaganda and political strategies, affecting pharmaceutical development both in the Western and the Eastern bloc. PMID:26054208

  12. 37 CFR 1.775 - Calculation of patent term extension for a human drug, antibiotic drug or human biological product.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... extension for a human drug, antibiotic drug or human biological product. 1.775 Section 1.775 Patents... Review § 1.775 Calculation of patent term extension for a human drug, antibiotic drug or human biological... drug or human biological product is eligible for extension, the term shall be extended by the time...

  13. 37 CFR 1.775 - Calculation of patent term extension for a human drug, antibiotic drug or human biological product.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... extension for a human drug, antibiotic drug or human biological product. 1.775 Section 1.775 Patents... Review § 1.775 Calculation of patent term extension for a human drug, antibiotic drug or human biological... drug or human biological product is eligible for extension, the term shall be extended by the time...

  14. 37 CFR 1.775 - Calculation of patent term extension for a human drug, antibiotic drug or human biological product.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... extension for a human drug, antibiotic drug or human biological product. 1.775 Section 1.775 Patents... Review § 1.775 Calculation of patent term extension for a human drug, antibiotic drug or human biological... drug or human biological product is eligible for extension, the term shall be extended by the time...

  15. 37 CFR 1.775 - Calculation of patent term extension for a human drug, antibiotic drug or human biological product.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... extension for a human drug, antibiotic drug or human biological product. 1.775 Section 1.775 Patents... Review § 1.775 Calculation of patent term extension for a human drug, antibiotic drug or human biological... drug or human biological product is eligible for extension, the term shall be extended by the time...

  16. 37 CFR 1.775 - Calculation of patent term extension for a human drug, antibiotic drug or human biological product.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... extension for a human drug, antibiotic drug or human biological product. 1.775 Section 1.775 Patents... Review § 1.775 Calculation of patent term extension for a human drug, antibiotic drug or human biological... drug or human biological product is eligible for extension, the term shall be extended by the time...

  17. Structural Requirements for CNS Active Opioid Glycopeptides.

    PubMed

    Lefever, Mark; Li, Yingxue; Anglin, Bobbi; Muthu, Dhanasekaran; Giuvelis, Denise; Lowery, John J; Knapp, Brian I; Bidlack, Jean M; Bilsky, Edward J; Polt, Robin

    2015-08-13

    Glycopeptides related to β-endorphin penetrate the blood-brain barrier (BBB) of mice to produce antinociception. Two series of glycopeptides were assessed for opioid receptor binding affinity. Attempts to alter the mu-selectivity of [D-Ala(2),N-MePhe(4),Gly-ol(5)]enkephalin (DAMGO)-related glycopeptides by altering the charged residues of the amphipathic helical address were unsuccessful. A series of pan-agonists was evaluated for antinociceptive activity (55 °C tail flick) in mice. A flexible linker was required to maintain antinociceptive activity. Circular dichroism (CD) in H2O, trifluoroethanol (TFE), and SDS micelles confirmed the importance of the amphipathic helices (11s → 11sG → 11) for antinociception. The glycosylated analogues showed only nascent helices and random coil conformations in H2O. Chemical shift indices (CSI) and nuclear Overhauser effects (NOE) with 600 MHz NMR and CD confirmed helical structures in micelles, which were rationalized by molecular dynamics calculations. Antinociceptive studies with mice confirm that these glycosylated endorphin analogues are potential drug candidates that penetrate the BBB to produce potent central effects. PMID:26125201

  18. Production of peptide antibiotics by Bacillus sp. GU 057 indigenously isolated from saline soil.

    PubMed

    Amin, Adnan; Khan, Muhammad Ayaz; Ehsanullah, Malik; Haroon, Uzma; Azam, Sheikh Muhammad Farooq; Hameed, Abdul

    2012-10-01

    A total of 112 soil samples were taken from differents areas of district D.I.Khan and Kohat (KPK) Pakistan and screened for production of antibiotics against the Micrococcus luteus and Staphylococcus aureus. Widest zone of inhibition (18mm) was produced by microorganism isolated from saline soil. The strain was later identified as Bacillus GU057 by standard biochemical assays. Maximum activity (18mm inhibition zone) was observed against Staphylococcus aureus after 48 hours of incubation at pH 8 and 4% concentration of glucose. The antibiotic was identified by autobiography as bacitracin. The Bacillus strain GU057 was confirmed as good peptide antibiotic producer and can effectively be indulged as biocontrol agent. PMID:24031962

  19. Production of peptide antibiotics by Bacillus sp. GU 057 indigenously isolated from saline soil

    PubMed Central

    Amin, Adnan; Khan, Muhammad Ayaz; Ehsanullah, Malik; Haroon, Uzma; Azam, Sheikh Muhammad Farooq; Hameed, Abdul

    2012-01-01

    A total of 112 soil samples were taken from differents areas of district D.I.Khan and Kohat (KPK) Pakistan and screened for production of antibiotics against the Micrococcus luteus and Staphylococcus aureus. Widest zone of inhibition (18mm) was produced by microorganism isolated from saline soil. The strain was later identified as Bacillus GU057 by standard biochemical assays. Maximum activity (18mm inhibition zone) was observed against Staphylococcus aureus after 48 hours of incubation at pH 8 and 4% concentration of glucose. The antibiotic was identified by autobiography as bacitracin. The Bacillus strain GU057 was confirmed as good peptide antibiotic producer and can effectively be indulged as biocontrol agent. PMID:24031962

  20. Lysozyme as an alternative to growth promoting antibiotics in swine production.

    PubMed

    Oliver, W T; Wells, J E

    2015-01-01

    Lysozyme is a naturally occurring enzyme found in bodily secretions such as tears, saliva, and milk. It functions as an antimicrobial agent by cleaving the peptidoglycan component of bacterial cell walls, which leads to cell death. Antibiotics are also antimicrobials and have been fed at subtherapeutic levels to swine as growth promoters. These compounds benefit swine producers by minimizing production losses by increasing feed efficiency and decreasing susceptibility to bacterial infection and disease. This manuscript reviews the knowledge of the effects of lysozyme, as compared to traditional subtherapeutic antibiotics in swine feed, on pig performance and health. It is clear from decades of studies that antibiotic use in feeds increases pig performance, particularly in the nursery. Similarly, lysozyme, as a feed additive, increases growth and feed efficiency. While the mechanism by which antibiotics and lysozyme improve performance is not clearly understood, both of these feed additives improve gastrointestinal health, improve the metabolic profile, and alter the gastrointestinal bacteria ecology of swine. Therefore, lysozyme is a suitable alternative to growth-promoting subtherapeutic antibiotic use in swine feed. PMID:26273432

  1. The Effect of Antibiotics on Associated Bacterial Community of Stored Product Mites

    PubMed Central

    Kopecky, Jan; Nesvorna, Marta; Mareckova-Sagova, Marketa; Hubert, Jan

    2014-01-01

    Background Bacteria are associated with the gut, fat bodies and reproductive organs of stored product mites (Acari: Astigmata). The mites are pests due to the production of allergens. Addition of antibiotics to diets can help to characterize the association between mites and bacteria. Methodology and Principal Findings Ampicillin, neomycin and streptomycin were added to the diets of mites and the effects on mite population growth (Acarus siro, Lepidoglyphus destructor and Tyrophagus putrescentiae) and associated bacterial community structure were assessed. Mites were treated by antibiotic supplementation (1 mgg−1 of diet) for 21 days and numbers of mites and bacterial communities were analyzed and compared to the untreated control. Bacterial quantities, determined by real-time PCR, significantly decreased in antibiotic treated specimens from 5 to 30 times in A. siro and T. putrescentiae, while no decline was observed in L. destructor. Streptomycin treatment eliminated Bartonella-like bacteria in the both A. siro and T. putrescentiae and Cardinium in T. putrescentiae. Solitalea-like bacteria proportion increased in the communities of neomycin and streptomycin treated A. siro specimens. Kocuria proportion increased in the bacterial communities of ampicillin and streptomycin treated A. siro and neomycin and streptomycin treated L. destructor. Conclusions/Significance The work demonstrated the changes of mite associated bacterial community under antibiotic pressure in pests of medical importance. Pre-treatment of mites by 1 mgg−1 antibiotic diets improved mite fitness as indicated accelerated population growth of A. siro pretreated streptomycin and neomycin and L. destructor pretreated by neomycin. All tested antibiotics supplemented to diets caused the decrease of mite growth rate in comparison to the control diet. PMID:25387104

  2. Natural Products as a Source for Novel Antibiotics.

    PubMed

    Moloney, Mark G

    2016-08-01

    Natural products have historically been of crucial importance in the identification and development of antibacterial agents. Interest in these systems has waned in recent years, but the rapid emergence of resistant bacterial strains has forced their re-evaluation as a route to identify novel chemical skeletons with antibacterial activity for elaboration in drug development. This overview examines the current situation, highlights new natural product systems which have been found, together with re-examination of some old ones, and new technologies for their identification. While natural products certainly have the potential to re-emerge as a key start-point in antibacterial drug discovery, reports of new or reinvestigated structures need to be supported with sufficient quality chemical (solubility, stability), biochemical (including toxicity in particular, along with target information) and microbiological [minimum inhibitory concentration (MIC) and resistance frequency] validation data to assist in the identification of promising hit structures and to avoid wasted effort from trawling over already cultivated territory. This is particularly important in a resource-limited research environment. PMID:27267698

  3. Novel Approach for Improving the Productivity of Antibiotic-Producing Strains by Inducing Combined Resistant Mutations

    PubMed Central

    Hu, Haifeng; Ochi, Kozo

    2001-01-01

    We developed a novel approach for improving the production of antibiotic from Streptomyces coelicolor A3(2) by inducing combined drug-resistant mutations. Mutants with enhanced (1.6- to 3-fold-higher) actinorhodin production were detected at a high frequency (5 to 10%) among isolates resistant to streptomycin (Strr), gentamicin (Genr), or rifampin (Rifr), which developed spontaneously on agar plates which contained one of the three drugs. Construction of double mutants (str gen and str rif) by introducing gentamicin or rifampin resistance into an str mutant resulted in further increased (1.7- to 2.5-fold-higher) actinorhodin productivity. Likewise, triple mutants (str gen rif) thus constructed were found to have an even greater ability for producing the antibiotic, eventually generating a mutant able to produce 48 times more actinorhodin than the wild-type strain. Analysis of str mutants revealed that a point mutation occurred within the rpsL gene, which encodes the ribosomal protein S12. rif mutants were found to have a point mutation in the rpoB gene, which encodes the β-subunit of RNA polymerase. Mutation points in gen mutants still remain unknown. These single, double, and triple mutants displayed in hierarchical order a remarkable increase in the production of ActII-ORF4, a pathway-specific regulatory protein, as determined by Western blotting analysis. This reflects the same hierarchical order observed for the increase in actinorhodin production. The superior ability of the triple mutants was demonstrated by physiological analyses under various cultural conditions. We conclude that by inducing combined drug-resistant mutations we can continuously increase the production of antibiotic in a stepwise manner. This new breeding approach could be especially effective for initially improving the production of antibiotics from wild-type strains. PMID:11282646

  4. Community structure and antibiotic production of Streptomyces nodosus bioreactors cultured in liquid environments

    PubMed Central

    Pereira, Tanya; Nikodinovic, Jasmina; Nakazono, Chojin; Dennis, Gary R.; Barrow, Kevin D.; Chuck, Jo‐Anne

    2008-01-01

    Summary Immobilized bacteria are being assessed by industry for drug delivery, novel fermentation systems and the protection of organisms in harsh environments. Alginate bioreactors containing Streptomyces nodosus were examined for community structure, cell viability and amphotericin production under different growth conditions. When cell proliferation was encouraged, substrate hyphae were found inside the alginate matrix and within multicellular projections on the surface of the capsule. The periphery of these projections had erect and branched hyphae, morphologically identical to aerial hyphae. Antibiotic production from immobilized organisms was assessed using conditioned culture medium to eliminate the emergence of a free‐dwelling population. These organisms sporulated with reduced antibiotic production compared with free‐dwelling cultures. The commitment to sporulate was independent of a surface but dependent on community size and nutritional status. This is the first report of the sporulation of S. nodosus in liquid cultures and description of the multicellular community the organism adopts at a solid–liquid interface. PMID:21261857

  5. Changes in GE2270 antibiotic production in Planobispora rosea through modulation of methylation metabolism.

    PubMed

    Gastaldo, Luciano; Marinelli, Flavia

    2003-06-01

    Thiazolylpeptide GE2270 is a potent antibiotic inhibiting protein synthesis in Gram-positive bacteria. It is produced as a complex of 10 related metabolites, differing mainly in the degree of methylation, by fermentation of the rare actinomycete Planobispora rosea ATCC 53773. Addition of vitamin B12 to the fermentation medium doubled total complex production and markedly changed the relative production of the various GE2270 metabolites, enhancing the biosynthesis of the more methylated component A. Among methylation inhibitors, the addition of sinefungin increased the amount of factor D2, which differs from component A in the lack of a methyl group. Since sinefungin is an S-adenosyl-L-methionine methyltransferase-specific inhibitor, these results indicate that the methylation step converting D2 into A involves an S-adenosyl-L-methionine methyltransferase. Simultaneous supplementation of vitamin B12 and sinefungin led to a twofold increase in D2 concentration, showing that vitamin B12, in addition to having an effect on the late methylation step, exerts a stimulating action on antibiotic backbone synthesis. This is possibly due to its role in an unusual pathway of serine synthesis peculiar to P. rosea metabolism. Finally, fermentation medium modifications were shown to be useful for the production of industrially valuable levels of components A or D2 in the GE2270 complex as starting points for the production of new interesting semi-synthetic antibiotics. PMID:12777492

  6. Increasing antibiotic resistance in preservative-tolerant bacterial strains isolated from cosmetic products.

    PubMed

    Orús, Pilar; Gomez-Perez, Laura; Leranoz, Sonia; Berlanga, Mercedes

    2015-03-01

    To ensure the microbiological quality, consumer safety and organoleptic properties of cosmetic products, manufacturers need to comply with defined standards using several preservatives and disinfectants. A drawback regarding the use of these preservatives is the possibility of generating cross-insusceptibility to other disinfectants or preservatives, as well as cross resistance to antibiotics. Therefore, the objective of this study was to understand the adaptive mechanisms of Enterobacter gergoviae, Pseudomonas putida and Burkholderia cepacia that are involved in recurrent contamination in cosmetic products containing preservatives. Diminished susceptibility to formaldehyde-donors was detected in isolates but not to other preservatives commonly used in the cosmetics industry, although increasing resistance to different antibiotics (β-lactams, quinolones, rifampicin, and tetracycline) was demonstrated in these strains when compared with the wild-type strain. The outer membrane protein modifications and efflux mechanism activities responsible for the resistance trait were evaluated. The development of antibiotic-resistant microorganisms due to the selective pressure from preservatives included in cosmetic products could be a risk for the emergence and spread of bacterial resistance in the environment. Nevertheless, the large contribution of disinfection and preservation cannot be denied in cosmetic products. PMID:26415667

  7. Hfq regulates antibacterial antibiotic biosynthesis and extracellular lytic-enzyme production in Lysobacter enzymogenes OH11.

    PubMed

    Xu, Gaoge; Zhao, Yuxin; Du, Liangcheng; Qian, Guoliang; Liu, Fengquan

    2015-05-01

    Lysobacter enzymogenes is an important biocontrol agent with the ability to produce a variety of lytic enzymes and novel antibiotics. Little is known about their regulatory mechanisms. Understanding these will be helpful for improving biocontrol of crop diseases and potential medical application. In the present study, we generated an hfq (encoding a putative ribonucleic acid chaperone) deletion mutant, and then utilized a new genomic marker-free method to construct an hfq-complemented strain. We showed for the first time that Hfq played a pleiotropic role in regulating the antibacterial antibiotic biosynthesis and extracellular lytic enzyme activity in L. enzymogenes. Mutation of hfq significantly increased the yield of WAP-8294A2 (an antibacterial antibiotic) as well as the transcription of its key biosynthetic gene, waps1. However, inactivation of hfq almost abolished the extracellular chitinase activity and remarkably decreased the activity of both extracellular protease and cellulase in L. enzymogenes. We further showed that the regulation of hfq in extracellular chitinase production was in part through the impairment of the secretion of chitinase A. Collectively, our results reveal the regulatory roles of hfq in antibiotic metabolite and extracellular lytic enzymes in the underexplored genus of Lysobacter. PMID:25683974

  8. Hfq regulates antibacterial antibiotic biosynthesis and extracellular lytic-enzyme production in Lysobacter enzymogenes OH11

    PubMed Central

    Xu, Gaoge; Zhao, Yuxin; Du, Liangcheng; Qian, Guoliang; Liu, Fengquan

    2015-01-01

    Lysobacter enzymogenes is an important biocontrol agent with the ability to produce a variety of lytic enzymes and novel antibiotics. Little is known about their regulatory mechanisms. Understanding these will be helpful for improving biocontrol of crop diseases and potential medical application. In the present study, we generated an hfq (encoding a putative ribonucleic acid chaperone) deletion mutant, and then utilized a new genomic marker-free method to construct an hfq-complemented strain. We showed for the first time that Hfq played a pleiotropic role in regulating the antibacterial antibiotic biosynthesis and extracellular lytic enzyme activity in L. enzymogenes. Mutation of hfq significantly increased the yield of WAP-8294A2 (an antibacterial antibiotic) as well as the transcription of its key biosynthetic gene, waps1. However, inactivation of hfq almost abolished the extracellular chitinase activity and remarkably decreased the activity of both extracellular protease and cellulase in L. enzymogenes. We further showed that the regulation of hfq in extracellular chitinase production was in part through the impairment of the secretion of chitinase A. Collectively, our results reveal the regulatory roles of hfq in antibiotic metabolite and extracellular lytic enzymes in the underexplored genus of Lysobacter. PMID:25683974

  9. Antibiotic resistance modulation by natural products obtained from Nasutitermes corniger (Motschulsky, 1855) and its nest.

    PubMed

    Chaves, Thiago P; Clementino, Elaine L C; Felismino, Delcio C; Alves, Rômulo R N; Vasconcellos, Alexandre; Coutinho, Henrique D M; Medeiros, Ana Cláudia D

    2015-07-01

    Insects and their products are included in the traditional pharmacopoeia of various ethnic groups worldwide. In the Brazilian semiarid region can be highlighted the use of the termite Nasutitermes corniger for the treatment of various diseases. This study evaluated the ethanol extract of N. corniger and its nest as an antimicrobial agent and as a modulator of bacterial resistance against multidrug strains. The Minimum Inhibitory Concentration (MIC) of the extract on Staphylococcus aureus and Escherichia coli by microdilution was determined, as well as MIC of antibiotics in the presence and absence of extract. Despite having no significant antimicrobial activity (MIC ⩾ 1000 μg mL(-1)), the extract showed additive activity to the antibiotic efficacy, significantly reducing its MIC. These results suggest that N. corniger and its nest are promising natural products for use in antimicrobial therapy. PMID:26150745

  10. [Simultaneous determination of polyether antibiotics and macrolide anthelmintics in livestock products by liquid chromatography/tandem mass spectrometry].

    PubMed

    Yamaguchi, Mizuka; Kakimoto, Kensaku; Yamaguchi, Takahiro; Obana, Hirotaka

    2011-01-01

    A method using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) was developed for the simultaneous determination of polyether antibiotics and macrolide anthelmintics in livestock products. The polyether antibiotics and macrolide anthelmintics were extracted from livestock products with acetonitrile and cleaned up with dispersive solid-phase extractions and a silica gel column. The quantification limits of polyether antibiotics and macrolide anthelmintics were 0.00005-0.0005 µg/g. Except for narasin and lasalocid in bovine liver and milk, the recoveries were 70 to 117%. The relative standard deviations met the required guideline. The developed method was applied to six kinds of livestock products. PMID:22200746

  11. Crystal Structures of Lipoglycopeptide Antibiotic Deacetylases: Implications for the Biosynthesis of A40926 and Teicoplanin

    SciTech Connect

    Zou, Yaozhong; Brunzelle, Joseph S.; Nair, Satish K.

    2008-07-08

    The lipoglycopeptide antibiotics teicoplanin and A40926 have proven efficacy against Gram-positive pathogens. These drugs are distinguished from glycopeptide antibiotics by N-linked long chain acyl-D-glucosamine decorations that contribute to antibacterial efficacy. During the biosynthesis of lipoglycopeptides, tailoring glycosyltransferases attach an N-acetyl-D-glucosamine to the aglycone, and this N-acetyl-glucosaminyl pseudoaglycone is deacetylated prior to long chain hydrocarbon attachment. Here we present several high-resolution crystal structures of the pseudoaglycone deacetylases from the biosynthetic pathways of teicoplanin and A40926. The cocrystal structure of the teicoplanin pseudoaglycone deacetylase with a fatty acid product provides further insights into the roles of active-site residues, and suggests mechanistic similarities with structurally distinct zinc deacetylases, such as peptidoglycan deacetylase and LpxC. A unique, structurally mobile capping lid, located at the apex of these pseudoaglycone deacetylases, likely serves as a determinant of substrate specificity.

  12. Synthetic Self-Adjuvanting Glycopeptide Cancer Vaccines

    NASA Astrophysics Data System (ADS)

    Payne, Richard; McDonald, David; Byrne, Scott

    2015-10-01

    Due to changes in glycosyltransferase expression during tumorigenesis, the glycoproteins of cancer cells often carry highly truncated carbohydrate chains compared to those on healthy cells. These glycans are known as tumor-associated carbohydrate antigens, and are prime targets for use in vaccines for the prevention and treatment of cancer. Herein, we review the state-of-the-art in targeting the immune system towards tumor-associated glycopeptide antigens via synthetic self adjuvanting vaccines, in which the antigenic and adjuvanting moieties of the vaccines are present in the same molecule. The majority of the self-adjuvanting glycopeptide cancer vaccines reported to date employ antigens from mucin 1, a protein which is highly over-expressed and aberrantly glycosylated in many forms of cancer. The adjuvants used in these vaccines predominantly include lipopeptide- or lipoamino acid-based TLR2 agonists, although studies investigating stimulation of TLR9 and TLR4 are also discussed. Most of these adjuvants are highly lipophilic, and, upon conjugation to antigenic peptides, provide amphiphilic vaccine molecules. The amphiphilic nature of these vaccine constructs can lead to the formation of higher-order structures by vaccines in solution, which are likely to be important for their efficacy in vivo.

  13. Glycopeptide Capture for Cell Surface Proteomics

    PubMed Central

    Lee, M. C. Gilbert; Sun, Bingyun

    2014-01-01

    Cell surface proteins, including extracellular matrix proteins, participate in all major cellular processes and functions, such as growth, differentiation, and proliferation. A comprehensive characterization of these proteins provides rich information for biomarker discovery, cell-type identification, and drug-target selection, as well as helping to advance our understanding of cellular biology and physiology. Surface proteins, however, pose significant analytical challenges, because of their inherently low abundance, high hydrophobicity, and heavy post-translational modifications. Taking advantage of the prevalent glycosylation on surface proteins, we introduce here a high-throughput glycopeptide-capture approach that integrates the advantages of several existing N-glycoproteomics means. Our method can enrich the glycopeptides derived from surface proteins and remove their glycans for facile proteomics using LC-MS. The resolved N-glycoproteome comprises the information of protein identity and quantity as well as their sites of glycosylation. This method has been applied to a series of studies in areas including cancer, stem cells, and drug toxicity. The limitation of the method lies in the low abundance of surface membrane proteins, such that a relatively large quantity of samples is required for this analysis compared to studies centered on cytosolic proteins. PMID:24836557

  14. Surface Membrane Glycopeptides Which Coincide with Virus Transformation and Tumorigenesis

    PubMed Central

    Glick, Mary Catherine; Rabinowitz, Zelig; Sachs, Leo

    1974-01-01

    Glycopeptides from the surface of clones of hamster embryo cells were examined at various intervals after infection with polyoma virus. Two types of transformed cells were examined: (i) clones that showed delayed transformation or an initially low tumorigenicity, and (ii) clones that were rapidly transformed showing an initially high tumorigenicity. The glycopeptides were removed from the cell surface by trypsin and, after Pronase digestion, were examined by filtration through Sephadex G-50. With delayed transformation, a specific group of glycopeptides was increasingly evident over an 85-day period as the cells showed phenotypic properties of transformation and the ability to form tumors. In the other series, all but one clone of hamster embryo cells showed rapid transformation after infection with polyoma virus. This clone was less tumorigenic and showed little of the specific glycopeptides. In all cases of delayed or rapid transformation examined, the specific group of glycopeptides increased proportionately to the ability of the cells to form tumors. All of the cells derived from progressively growing tumors formed by injection of these transformed hamster cells into adult animals showed an abundance of this group of glycopeptides. These results suggest that specific surface membrane glycopeptides accompany viral transformation and tumorigenesis. PMID:4363256

  15. 60Co irradiation for sterilization of veterinary mastitis products containing antibiotics and steroids

    NASA Astrophysics Data System (ADS)

    Tsuji, K.; Kane, M. P.; Rahn, P. D.; Steindler, K. A.

    Effects of 60Co irradiation for sterilization of veterinary mastitis products were evaluated. The mastitis products which were examined contained various combinations of antibiotics and steroids suspended in peanut oil vehicle. Bioburden data indicated that the unirradiated products were only occasionally contaminated with microorganisms. The D-values of the nonsterile product and environmental isolates were 0.028, 0.15, 0.017, and 0.018 Mrads for Aspergillus fumigatus, Penicillium oxalicum, Pseudomonas aeruginosa, and Pseudomonas maltophilia, respectively. The D-value of the biological indicator organism, Bacillus pumilus spores, in the vehicle was 0.27 Mrads. Thus, an irradiation dose of 1.6 Mrads would be sufficient to achieve six log cycles of destruction of the biological indicator organism. The minimum absorbed irradiation dose of 2.5 Mrads preferred by many countries for sterilization would achieve 9.3 log cycle destruction of the indicator organism and guarantee a probability of 1 × 10 -15 assurance for the most radio-resistant product isolate, Penicillium oxalicum. In order to examine short and long term chemical stabilities of active components, stability indicating high-performance liquid chromatographic (HPLC) methods for the determination of the following antibiotics and steroids were developed. They were: dihydrostreptomycin, neomycin, novobiocin, penicillin G, hydrocortisone acetate, hydrocortisone sodium succinate, and prednisolone. The rates of degradation and radiolytic degradation schemes for the majority of these compounds were elucidated. Formation of new compounds was not observed in these antibiotics and steroids upon 60Co irradiation. The compounds that increased by irradiation were inherently present in commercially available non-irradiated lots and/or can easily be formed by either acidic, basic, or thermal treatment.

  16. Degradation of fluoroquinolone antibiotics by ferrate(VI): Effects of water constituents and oxidized products.

    PubMed

    Feng, Mingbao; Wang, Xinghao; Chen, Jing; Qu, Ruijuan; Sui, Yunxia; Cizmas, Leslie; Wang, Zunyao; Sharma, Virender K

    2016-10-15

    The degradation of five fluoroquinolone (FQ) antibiotics (flumequine (FLU), enrofloxacin (ENR), norfloxacin (NOR), ofloxacin (OFL) and marbofloxacin (MAR)) by ferrate(VI) (Fe(VI)O4(2-), Fe(VI)) was examined to demonstrate the potential of this iron-based chemical oxidant to treat antibiotics in water. Experiments were conducted at different molar ratios of Fe(VI) to FQs at pH 7.0. All FQs, except FLU, were degraded within 2 min at [Fe(VI)]:[FQ] ≤ 20.0. Multiple additions of Fe(VI) improved the degradation efficiency, and provided greater degradation than a single addition of Fe(VI). The effects of anions, cations, and humic acid (HA), usually present in source waters and wastewaters, on the removal of FLU were investigated. Anions (Cl(-), SO4(2-), NO3(-), and HCO3(-)) and monovalent cations (Na(+) and K(+)) had no influence on the removal of FLU. However, multivalent cations (Ca(2+), Mg(2+), Cu(2+), and Fe(3+)) in water decreased the efficiency of FLU removal by Fe(VI). An increase in the ionic strength of the solution, and the presence of HA in the water, also decreased the percentage of FLU removed by Fe(VI). Experiments on the removal of selected FQs, present as co-existing antibiotics in pure water, river water, synthetic water and wastewater, were also conducted to demonstrate the practical application of Fe(VI) to remove the antibiotics during water treatment. The seventeen oxidized products (OPs) of FLU were identified using solid phase extraction-liquid chromatography-high-resolution mass spectrometry. The reaction pathways are proposed, and are theoretically confirmed by molecular orbital calculations. PMID:27429354

  17. Immunological Evaluation of Recent MUC1 Glycopeptide Cancer Vaccines.

    PubMed

    Hossain, Md Kamal; Wall, Katherine A

    2016-01-01

    Aberrantly glycosylated mucin 1 (MUC1) is a recognized tumor-specific antigen on epithelial cell tumors. A wide variety of MUC1 glycopeptide anti-cancer vaccines have been formulated by many research groups. Some researchers have used MUC1 alone as an immunogen whereas other groups used different antigenic carrier proteins such as bovine serum albumin or keyhole limpet hemocyanin for conjugation with MUC1 glycopeptide. A variety of adjuvants have been used with MUC1 glycopeptides to improve their immunogenicity. Fully synthetic multicomponent vaccines have been synthesized by incorporating different T helper cell epitopes and Toll-like receptor agonists. Some vaccine formulations utilized liposomes or nanoparticles as vaccine delivery systems. In this review, we discuss the immunological evaluation of different conjugate or synthetic MUC1 glycopeptide vaccines in different tumor or mouse models that have been published since 2012. PMID:27472370

  18. Potentiation of antibiotic activity of aminoglycosides by natural products from Cordia verbenacea DC.

    PubMed

    Matias, Edinardo F F; Alves, Erivania F; Silva, Maria K N; Carvalho, Victoria R A; Medeiros, Cassio R; Santos, Francisco A V; Bitu, Vanessa C N; Souza, Celestina E S; Figueredo, Fernando G; Boligon, Aline A; Athayde, Margareth L; Costa, José G M; Coutinho, Henrique D M

    2016-06-01

    Medicinal plants are often the only therapeutic resource for many communities and ethnic groups. Cordia verbenacea DC., "Erva-baleeira," is one of the species of plants currently used to produce a phytotherapeutic product extracted from its leaves. The present study aimed to establish its chemical profile, antibacterial activity and resistance-modulating potential. The C. verbenacea extracts were prepared from fresh leaves using solvents as methanol and hexane. Ethyl Acetate was used for the preparation of the fraction. Phytochemical screening was carried out using HPLC-DAD for determination and quantification of the secondary metabolites present in the fractions. Antibacterial and resistance-modulation assays were performed to determine minimum inhibitory concentration (MIC) using a microdilution assay. The data were subjected to statistical analysis with two-way ANOVA and Bonferroni posttests. Results of phytochemical prospecting and HPLC analysis of the fractions were in agreement with the literature. The natural products presented moderate antibacterial activity when considering the clinical relevance of a MIC of 256 μg/mL against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa, and 512 μg/mL against P. aeruginosa. However, when the fractions were combined with antibiotics we observed a synergic effect, as natural products enhanced the antibacterial effect of aminoglycosides, significantly decreasing the MIC of antibiotics at 12.5%-98.4%. We believe that the data obtained from phytochemical analysis and from antibacterial and resistance modulation assays of C. verbenacea extracts new can open perspectives in the search for new alternatives for the treatment of bacterial infections and stimulate the renewed use of antibiotics with reduced effectiveness due to resistance. PMID:27033000

  19. Production of fungal antibiotics using polymeric solid supports in solid-state and liquid fermentation.

    PubMed

    Bigelis, Ramunas; He, Haiyin; Yang, Hui Y; Chang, Li-Ping; Greenstein, Michael

    2006-10-01

    The use of inert absorbent polymeric supports for cellular attachment in solid-state fungal fermentation influenced growth, morphology, and production of bioactive secondary metabolites. Two filamentous fungi exemplified the utility of this approach to facilitate the discovery of new antimicrobial compounds. Cylindrocarpon sp. LL-Cyan426 produced pyrrocidines A and B and Acremonium sp. LL-Cyan416 produced acremonidins A-E when grown on agar bearing moist polyester-cellulose paper and generated distinctly different metabolite profiles than the conventional shaken or stationary liquid fermentations. Differences were also apparent when tenfold concentrated methanol extracts from these fermentations were tested against antibiotic-susceptible and antibiotic-resistant Gram-positive bacteria, and zones of inhibition were compared. Shaken broth cultures of Acremonium sp. or Cylindrocarpon sp. showed complex HPLC patterns, lower levels of target compounds, and high levels of unwanted compounds and medium components, while agar/solid support cultures showed significantly increased yields of pyrrocidines A and B and acremonidins A-E, respectively. This method, mixed-phase fermentation (fermentation with an inert solid support bearing liquid medium), exploited the increase in surface area available for fungal growth on the supports and the tendency of some microorganisms to adhere to solid surfaces, possibly mimicking their natural growth habits. The production of dimeric anthraquinones by Penicillium sp. LL-WF159 was investigated in liquid fermentation using various inert polymeric immobilization supports composed of polypropylene, polypropylene cellulose, polyester-cellulose, or polyurethane. This culture produced rugulosin, skyrin, flavomannin, and a new bisanthracene, WF159-A, after fermentation in the presence and absence of polymeric supports for mycelial attachment. The physical nature of the different support systems influenced culture morphology and relative

  20. Characterization of immunoglobulins through analysis of N-glycopeptides by MALDI-TOF MS.

    PubMed

    Komatsu, Emy; Buist, Marjorie; Roy, Rini; Gomes de Oliveira, Andrey Giovanni; Bodnar, Edward; Salama, Apolline; Soulillou, Jean-Paul; Perreault, Hélène

    2016-07-15

    The aim of this report is to emphasize the role, usefulness and power of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) in the analysis of glycoforms of antibodies (Abs) through their proteolytic glycopeptides. Abs are complex biomolecules in which glycans hold determinant properties and thus need to be thoroughly characterized following Ab production by recombinant methods or Ab collection from human/animal serum or tissue. In spite of the great robustness of MALDI-TOF MS in terms of tolerance to impurities, the analysis of Abs and Ab components using this technique requires extensive sample preparation involving all or some of chromatography, solid phase extraction, enzymatic modification, and chemical derivatization. This report focuses on a monoclonal Ab produced in cell culture, as well as on a polyclonal human immunoglobulin (Ig) G obtained commercially and a polyclonal porcine IgG obtained from serum. A method is first provided to separate Ab protein chain components (light chains, heavy chains) by gel electrophoresis, which is useful for instance for protein-A eluates of Igs either from cell culture or biological samples. This allows for in-gel proteolytic digestion of the protein gel band(s) of choice for further MS characterization. Also discussed is the more conventional in-solution overnight digestion method used here with each of two proteolytic enzymes, i.e. trypsin and chymotrypsin. The overnight method is in turn compared with a much faster approach, that of digesting Abs with trypsin or chymotrypsin through the action of microwave heating. For method comparison, glycopeptides are fractionated from digestion mixtures using mostly C-18 cartridges for simplicity, although this enrichment procedure is also compared with other published procedures. The advantages of MALDI tandem mass spectrometry are highlighted for glycopeptide analysis, and lastly an esterification method applied to glycopeptides is

  1. Prevalence of LRTI in Patients Presenting with Productive Cough and Their Antibiotic Resistance Pattern

    PubMed Central

    Vijay, Sunil

    2016-01-01

    Aim To find out the prevalence of Lower Respiratory Tract Infection (LRTI) such as bacterial, fungal, mycobacterial infections etc. in patients with productive cough of duration less than 15 days and to rule out the patients having previous history of tuberculosis or having treatment of tuberculosis. Materials and Methods Outdoor and Indoor patients of Department of Medicine and Chest & TB, SRG hospital and Jhalawar Medical College, Jhalawar were included. After sample collection the specimens were sent to the Microbiology department, for processing of Gram staining, Acid fast staining, KOH mount and bacteriological culture and sensitivity. Results A total of 200 samples were obtained from the outpatient and inpatient Department of Medicine and Chest & TB of which 66% were male and 34% were female. Seventy seven percent of samples were culture positive for both single pathogen and mixed infection of which 56.5% were male and 20.5% were female as males are more at risk for LRTI. Klebsiella pneumoniae was the most prevalent pathogen (71/193), followed by coagulase positive Staphylococci i.e. COPS (43/193). More resistant pattern was found in coagulase negative Staohylococci (CONS) showed 61.11% Methicillin Resistant Staohylococci (MRS) incidence compared to 41.86% in COPS, also regarding Extended Spectrum Beta Lactamase (ESBL) production Escherichia coli showed incidence of 36.36% as compared to other gram negative bacilli. Pseudomonas aeruginosa was the most resistant organism found based on the antibiotic susceptibility pattern while Proteus mirabilis was the most sensitive organism. Conclusion Lower respiratory tract infections can spread easily among community and indiscriminate use of antibiotics contributes to their therapeutic failure. Area-wise studies on antimicrobial susceptibility profiles are essential to guide policy on the appropriate use of antibiotics to reduce the morbidity and mortality and also to control the emergence of antimicrobial resistance

  2. Concurrent automated sequencing of the glycan and peptide portions of O-linked glycopeptide anions by ultraviolet photodissociation mass spectrometry.

    PubMed

    Madsen, James A; Ko, Byoung Joon; Xu, Hua; Iwashkiw, Jeremy A; Robotham, Scott A; Shaw, Jared B; Feldman, Mario F; Brodbelt, Jennifer S

    2013-10-01

    O-Glycopeptides are often acidic owing to the frequent occurrence of acidic saccharides in the glycan, rendering traditional proteomic workflows that rely on positive mode tandem mass spectrometry (MS/MS) less effective. In this report, we demonstrate the utility of negative mode ultraviolet photodissociation (UVPD) MS for the characterization of acidic O-linked glycopeptide anions. This method was evaluated for a series of singly and multiply deprotonated glycopeptides from the model glycoprotein kappa casein, resulting in production of both peptide and glycan product ions that afforded 100% sequence coverage of the peptide and glycan moieties from a single MS/MS event. The most abundant and frequent peptide sequence ions were a/x-type products which, importantly, were found to retain the labile glycan modifications. The glycan-specific ions mainly arose from glycosidic bond cleavages (B, Y, C, and Z ions) in addition to some less common cross-ring cleavages. On the basis of the UVPD fragmentation patterns, an automated database searching strategy (based on the MassMatrix algorithm) was designed that is specific for the analysis of glycopeptide anions by UVPD. This algorithm was used to identify glycopeptides from mixtures of glycosylated and nonglycosylated peptides, sequence both glycan and peptide moieties simultaneously, and pinpoint the correct site(s) of glycosylation. This methodology was applied to uncover novel site-specificity of the O-linked glycosylated OmpA/MotB from the "superbug" A. baumannii to help aid in the elucidation of the functional role that protein glycosylation plays in pathogenesis. PMID:24006841

  3. Resistance to colistin: what is the fate for this antibiotic in pig production?

    PubMed

    Rhouma, Mohamed; Beaudry, Francis; Letellier, Ann

    2016-08-01

    Colistin, a cationic polypeptide antibiotic, has reappeared in human medicine as a last-line treatment option for multidrug-resistant Gram-negative bacteria (MDR-GNB). Colistin is widely used in veterinary medicine for the treatment of gastrointestinal infections caused by Enterobacteriaceae. GNB resistant to colistin owing to chromosomal mutations have already been reported both in human and veterinary medicine, however several recent studies have just identified a plasmid-mediated mcr-1 gene encoding for colistin resistance in Escherichia coli colistin resistance. The discovery of a non-chromosomal mechanism of colistin resistance in E. coli has led to strong reactions in the scientific community and to concern among physicians and veterinarians. Colistin use in food animals and particularly in pig production has been singled out as responsible for the emergence of colistin resistance. The present review will focus mainly on the possible link between colistin use in pigs and the spread of colistin resistance in Enterobacteriaceae. First we demonstrate a possible link between Enterobacteriaceae resistance emergence and oral colistin pharmacokinetics/pharmacodynamics and its administration modalities in pigs. We then discuss the potential impact of colistin use in pigs on public health with respect to resistance. We believe that colistin use in pig production should be re-evaluated and its dosing and usage optimised. Moreover, the search for competitive alternatives to using colistin with swine is of paramount importance to preserve the effectiveness of this antibiotic for the treatment of MDR-GNB infections in human medicine. PMID:27234675

  4. Different Dynamic Patterns of β-Lactams, Quinolones, Glycopeptides and Macrolides on Mouse Gut Microbial Diversity.

    PubMed

    Yin, Jia; M, Prabhakar; Wang, Shan; Liao, Shuo-Xi; Peng, Xin; He, Yan; Chen, Yi-Ran; Shen, Hua-Fang; Su, Jin; Chen, Ye; Jiang, Yun-Xia; Zhang, Guo-Xia; Zhou, Hong-Wei

    2015-01-01

    The adverse impact of antibiotics on the gut microbiota has attracted extensive interest, particularly due to the development of microbiome research techniques in recent years. However, a direct comparison of the dynamic effects of various types of antibiotics using the same animal model has not been available. In the present study, we selected six antibiotics from four categories with the broadest clinical usage, namely, β-lactams (Ceftriaxone Sodium, Cefoperazone/Sulbactam and meropenem), quinolones (ofloxacin), glycopeptides (vancomycin), and macrolides (azithromycin), to treat BALB/c mice. Stool samples were collected during and after the administration of antibiotics, and microbial diversity was analyzed through Illumina sequencing and bioinformatics analyses using QIIME. Both α and β diversity analyses showed that ceftriaxone sodium, cefoperazone/sulbactam, meropenem and vancomycin changed the gut microbiota dramatically by the second day of antibiotic administration whereas the influence of ofloxacin was trivial. Azithromycin clearly changed the gut microbiota but much less than vancomycin and the β-lactams. In general, the community changes induced by the three β-lactam antibiotics showed consistency in inhibiting Papillibacter, Prevotella and Alistipes while inducing massive growth of Clostridium. The low diversity and high Clostridium level might be an important cause of Clostridium difficile infection after usage of β-lactams. Vancomycin was unique in that it inhibited Firmicutes, mainly the genus Clostridium. On the other hand, it induced the growth of Escherichia and effect lasted for months afterward. Azithromycin and meropenem induced the growth of Enterococcus. These findings will be useful for understanding the potential adverse effects of antibiotics on the gut microbiome and ensuring their better usage. PMID:25970622

  5. Disruption of cagA, the apoprotein gene of chromoprotein antibiotic C-1027, eliminates holo-antibiotic production, but not the cytotoxic chromophore.

    PubMed

    Cui, Zhihui; Wang, Lifei; Wang, Songmei; Li, Guangwei; Hong, Bin

    2009-11-01

    C-1027 is a chromoprotein of the nine-membered enediyne antitumour antibiotic family, comprising apoprotein to stabilize and transport the enediyne chromophore. The disruption of apoprotein gene cagA within the C-1027 biosynthetic gene cluster abolished C-1027 holo-antibiotic production detected by an antibacterial assay, as well as the expression of the apoprotein and C-1027 chromophore extracted following protein precipitation of the culture supernatant. Complementation of the cagA-disrupted mutant AKO with the intact cagA gene restored C-1027 production, suggesting that cagA is indispensable for holo-antibiotic production. Overexpression of cagA in the wild-type strain resulted in a significant increase in C-1027 production as expected. Surprisingly, electrospray ionization (ESI)-MS and ESI-MS/MS analyses suggested that the AKO mutant still produced the C-1027 enediyne chromophore [m/z=844 (M+H)(+)] and its aromatized product [m/z=846 (M+H)(+)]. Consistent with this, the results from gene expression analysis using real-time reverse transcriptase-PCR showed that transcripts of the positive regulator sgcR3 and the structural genes sgcA1, sgcC4, sgcD6 and sgcE were readily detected in the AKO mutant as well as in the wild-type and the complementation strain. These results provided, for the first time, evidence suggesting that the apoprotein of C-1027 is not essential in the self-resistance mechanism for the enediyne chromophore. PMID:19845765

  6. Antibiotics and sweeteners in the aquatic environment: biodegradability, formation of phototransformation products, and in vitro toxicity.

    PubMed

    Bergheim, Marlies; Gminski, Richard; Spangenberg, Bernd; Debiak, Malgorzata; Bürkle, Alexander; Mersch-Sundermann, Volker; Kümmerer, Klaus; Gieré, Reto

    2015-11-01

    In the present study, in vitro toxicity as well as biopersistence and photopersistence of four artificial sweeteners (acesulfame, cyclamate, saccharine, and sucralose) and five antibiotics (levofloxacin, lincomycin, linezolid, marbofloxacin, and sarafloxacin) and of their phototransformation products (PTPs) were investigated. Furthermore, antibiotic activity was evaluated after UV irradiation and after exposure to inocula of a sewage treatment plant. The study reveals that most of the tested compounds and their PTPs were neither readily nor inherently biodegradable in the Organisation for Economic Co-operation and Development (OECD)-biodegradability tests. The study further demonstrates that PTPs are formed upon irradiation with an Hg lamp (UV light) and, to a lesser extent, upon irradiation with a Xe lamp (mimics sunlight). Comparing the nonirradiated with the corresponding irradiated solutions, a higher chronic toxicity against bacteria was found for the irradiated solutions of linezolid. Neither cytotoxicity nor genotoxicity was found in human cervical (HeLa) and liver (Hep-G2) cells for any of the investigated compounds or their PTPs. Antimicrobial activity of the tested fluoroquinolones was reduced after UV treatment, but it was not reduced after a 28-day exposure to inocula of a sewage treatment plant. This comparative study shows that PTPs can be formed as a result of UV treatment. The study further demonstrated that UV irradiation can be effective in reducing the antimicrobial activity of antibiotics, and consequently may help to reduce antimicrobial resistance in wastewaters. Nevertheless, the study also highlights that some PTPs may exhibit a higher ecotoxicity than the respective parent compounds. Consequently, UV treatment does not transform all micropollutants into harmless compounds and may not be a large-scale effluent treatment option. PMID:26169816

  7. Improvement of production of lipopeptide antibiotic iturin A using fish protein.

    PubMed

    Zohora, Umme Salma; Rahman, Mohammad Shahedur; Khan, Abdul Wahab; Okanami, Masahiro; Ano, Takashi

    2013-12-01

    To enhance the production of lipopeptide antibiotic iturin A, nutrient contents of the culture mediums were investigated in both submerged and biofilm fermentations. As a carbon source maltose and as nitrogen source, fish protein was used. In submerged fermentation maltose uptake was found lower (12%) compared to biofilm fermentation (15%) that was associated with higher cellular growth in biofilm. However, requirement of nitrogen (fish protein) concentration was found similar in both submerged and biofilm fermentations. Production of iturin A in submerged fermentation with 12% maltose and 5% fish protein was 4450 mg/L, and in biofilm fermentation it was 5050 mg/L when 15% maltose and 5% fish protein was used. PMID:25078830

  8. Chemoreactive Natural Products that Afford Resistance Against Disparate Antibiotics and Toxins.

    PubMed

    Du, Lin; You, Jianlan; Nicholas, Kenneth M; Cichewicz, Robert H

    2016-03-18

    Microorganisms use chemical inactivation strategies to circumvent toxicity caused by many types of antibiotics. Yet in all reported cases, this approach is limited to enzymatically facilitated mechanisms that each target narrow ranges of chemically related scaffolds. The fungus-derived shikimate analogues, pericoxide and pericosine A, were identified as chemoreactive natural products that attenuate the antagonistic effects of several synthetic and naturally derived antifungal agents. Experimental and computational studies suggest that pericoxide and pericosine A readily react via SN 2' mechanisms against a variety of nucleophilic substances under both in vitro aqueous and in situ co-culture conditions. Many of the substitution products from this reaction were highly stable and exhibited diminished toxicities against environmental fungal isolates, including the Tolypocladium sp. strain that produced pericoxide and pericosine A. PMID:26928999

  9. Stigmatellin, a new antibiotic from Stigmatella aurantiaca (Myxobacterales). I. Production, physico-chemical and biological properties.

    PubMed

    Kunze, B; Kemmer, T; Höfle, G; Reichenbach, H

    1984-05-01

    An antibiotic activity was extracted from the cell mass of the myxobacterium, Stigmatella aurantiaca strain Sg a15. The antibiotic was toxic for yeasts and filamentous fungi, but not for most bacteria. The compound had the molecular formula C30H42O7, appears to be a new antibiotic, and was named stigmatellin. In addition to stigmatellin, the strain produced relatively large quantities of a second, structurally unrelated antibiotic, a mixture of three myxalamid homologues. PMID:6429114

  10. Complex marine natural products as potential epigenetic and production regulators of antibiotics from a marine Pseudomonas aeruginosa

    PubMed Central

    Wang, Bin; Waters, Amanda L.; Sims, James W.; Fullmer, Alexis; Ellison, Serena; Hamann, Mark T.

    2013-01-01

    Marine microbes are capable of producing secondary metabolites for defense and competition. Factors exerting an impact on secondary metabolite production of microbial communities included bioactive natural products and co-culturing. These external influences may have practical applications such as increased yields or the generation of new metabolites from otherwise silent genes in addition to reducing or limiting the production of undesirable metabolites. In this paper, we discuss the metabolic profiles of a marine Pseudomonas aeruginosa in the presence of a number of potential chemical epigenetic regulators, adjusting carbon sources and co-culturing with other microbes to induce a competitive response. As a result of these stressors certain groups of antibiotics or antimalarial agents were increased most notably when treating P. aeruginosa with sceptrin and co-culturing with another Pseudomonas sp. An interesting cross-talking event between these two Pseudomonas species when cultured together and exposed to sceptrin was observed. PMID:23563743

  11. Production of polypeptide antibiotic from Streptomyces parvulus and its antibacterial activity

    PubMed Central

    Shetty, Prakasham Reddy; Buddana, Sudheer Kumar; Tatipamula, Vinay Bharadwaj; Naga, Yaswanth Varanasi Venkata; Ahmad, Jamal

    2014-01-01

    A highly potent secondary metabolite producing actinomycetes strain is isolated from marine soil sediments of Visakhapatnam sea coast, Bay of Bengal. Over all ten strains are isolated from the collected soil sediments. Among the ten actinomycetes strains the broad spectrum strain RSPSN2 was selected for molecular characterization, antibiotic production and its purification. The nucleotide sequence of the 1 rRNA gene (1261 base pairs) of the most potent strain evidenced a 96% similarity with Streptomyces parvulus 1044 strain, Streptomyces parvulus NBRC 13193 and Streptomyces parvulus BY-F. From the taxonomic features, the actinomycetes isolate RSPSN2 matches with Streptomyces parvulus in the morphological, physiological and biochemical characters. Thus, it was given the suggested name Streptomyces parvulus RSPSN2. The active metabolite was extracted using ethyl acetate (1:3, v/v) at pH 7.0. The separation of active ingredient and its purification was performed by using both thin layer chromatography (TLC) and column chromatography (CC) techniques. Spectrometric studies such as UV-visible, FTIR, and NMR and mass were performed. The antibacterial activity of pure compound was performed by cup plate method against some pathogenic bacteria including of streptomycin resistant bacteria like (Pseudomonas mirabilis, Pseudomonas putida and Bacillus cereus). In conclusion, the collected data emphasized the fact that a polypeptide antibiotic (Actinomycin D) was produced by Streptomyces parvulus RSPSN2. PMID:24948949

  12. A new approach for the synthesis of O-glycopeptides through a combination of solid-phase glycosylation and fluorous tagging chemistry (SHGPFT).

    PubMed

    Liu, Bo; Zhang, Fa; Zhang, Yan; Liu, Gang

    2014-03-28

    Glycoproteins and glycopeptides play important roles in various physiological and pathophysiological processes. Efficient preparation of glycopeptides with a specific structure is one of the pivotal areas in current chemistry research. In this article, a new SHGPFT approach to the synthesis and efficient purification of O-glycosylated peptides is developed by combining a solid-phase glycosylation and a light-fluorous glycosyl donor protocol. The desired product is finally isolated from the side products in the cleaved mixture by an efficient fluorous solid-phase extraction (F-SPE) step. PMID:24519332

  13. Finding alternatives to antibiotics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The spread of antibiotic-resistant pathogens requires new treatments. The availability of new antibiotics has severely declined, and so alternatives to antibiotics need to be considered in both animal agriculture and human medicine. Products for disease prevention are different than products for d...

  14. Potential Impact of Increased Use of Biocides in Consumer Products on Prevalence of Antibiotic Resistance

    PubMed Central

    Gilbert, Peter; McBain, Andrew J.

    2003-01-01

    There has recently been much controversy surrounding the increased use of antibacterial substances in a wide range of consumer products and the possibility that, as with antibiotics, indiscriminate use of biocides might contribute to the overall pattern of susceptibility in the general environment and in the clinic. Such speculation, based on the isolation of resistant mutants from in vitro monoculture experiments, is not reflected by an emergence of biocide-resistant strains in vivo. This review provides a broad coverage of the biocide and resistance literature and evaluates the potential risks, perceived from such laboratory monoculture experiments, against evidence gathered over 50 years of field studies. An explanation for the continued effectiveness of broad-spectrum biocidal agents against the decline in efficacy of therapeutic agents is provided based on the fitness costs of resistance and the ubiquity of naturally occurring substances that possess antibacterial effect. While we conclude from this review of the literature that the incorporation of antibacterial agents into a widening sphere of personal products has had little or no impact on the patterns of microbial susceptibility observed in the environment, the associated risks remain finite. The use of such products should therefore be associated with a clear demonstration of added value either to consumer health or to the product life. Hygienic products should therefore be targeted to applications for which the risks have been established. PMID:12692093

  15. Gold nanostructure-integrated silica-on-silicon waveguide for the detection of antibiotics in milk and milk products

    NASA Astrophysics Data System (ADS)

    Ozhikandathil, Jayan; Badilescu, Simona; Packirisamy, Muthukumaran

    2012-10-01

    Antibiotics are extensively used in veterinary medicine for the treatment of infectious diseases. The use of antibiotics for the treatment of animals used for food production raised the concern of the public and a rapid screening method became necessary. A novel approach of detection of antibiotics in milk is reported in this work by using an immunoassay format and the Localized Surface Plasmon Resonance property of gold. An antibiotic from the penicillin family that is, ampicillin is used for testing. Gold nanostructures deposited on a glass substrate by a novel convective assembly method were heat-treated to form a nanoisland morphology. The Au nanostructures were functionalized and the corresponding antibody was absorbed from a solution. Solutions with known concentrations of antigen (antibiotics) were subsequently added and the spectral changes were monitored step by step. The Au LSPR band corresponding to the nano-island structure was found to be suitable for the detection of the antibody antigen interaction. The detection of the ampicillin was successfully demonstrated with the gold nano-islands deposited on glass substrate. This process was subsequently adapted for the integration of gold nanostructures on the silica-on-silicon waveguide for the purpose of detecting antibiotics.

  16. Synthesis and evaluation of carboxymethyl chitosan for glycopeptide enrichment.

    PubMed

    Bodnar, Edward D; Perreault, Hélène

    2015-09-01

    Glycans are known to be involved in a variety of biological processes throughout human physiology. Mass spectrometry has demonstrated itself as powerful analytical tool for quantitative and structural characterization of glycans. Studying these molecules at the glycopeptide level however, offers distinct advantages, namely the ability to characterize both the glycan and peptide fragments simultaneously, and moreover the ability to assign site specific heterogeneity. In light of this, peptides often dominate the spectrum and hinder the ionization efficiency of glycopeptides. For this reason, enrichment protocols prior to downstream MS analysis need to be developed. Here, we discuss the synthesis and use of carboxymethyl chitosan (CMCH) to enrich glycopeptides from a 12 protein mixture for MS analysis. This protocol was compared to a commercially available glycopeptide enrichment kit offered by EMD Millipore through the use of tandem mass tags (TMT) for relative quantification. Using this approach, we identified 98 unique N-linked glycopeptides and observed, that CMCH was able to enrich more sialylation than the commercial kit. In addition, we observed a trend based on TMT reporter ratios with respect to increasing sialylation. This corroborated that this stationary phase was exhibiting a mixed-mode enrichment through both hydrophilic interaction liquid chromatography (HILIC) and weak anion exchange (WAX) principles. PMID:26388377

  17. Resolving Isomeric Glycopeptide Glycoforms with Hydrophilic Interaction Chromatography (HILIC).

    PubMed

    Huang, Yining; Nie, Yongxin; Boyes, Barry; Orlando, Ron

    2016-09-01

    The ability to resolve glycans while attached to tryptic peptides would greatly facilitate glycoproteomics, as this would enable site-specific glycan characterization. Peptide/glycopeptide separations are typically performed using reversed-phase liquid chromatography (RPLC), where retention is driven by hydrophobic interaction. As the hydrophilic glycans do not interact significantly with the RPLC stationary phase, it is difficult to resolve glycopeptides that differ only in their glycan structure, even when these differences are large. Alternatively, glycans interact extensively with the stationary phases used in hydrophilic interaction chromatography (HILIC), and consequently, differences in glycan structure have profound chromatographic shifts in this chromatographic mode. Here, we evaluate HILIC for the separation of isomeric glycopeptide mixtures that have the same peptide backbone but isomeric glycans. Hydrophilic functional groups on both the peptide and the glycan interact with the HILIC stationary phase, and thus, changes to either of these moieties can alter the chromatographic behavior of a glycopeptide. The interactive processes permit glycopeptides to be resolved from each other based on differences in their amino acid sequences and/or their attached glycans. The separations of glycans in HILIC are sufficient to permit resolution of isomeric N-glycan structures, such as sialylated N-glycan isomers differing in α2-3 and α2-6 linkages, while these glycans remain attached to peptides. PMID:27582638

  18. Resolving Isomeric Glycopeptide Glycoforms with Hydrophilic Interaction Chromatography (HILIC)

    PubMed Central

    Huang, Yining; Nie, Yongxin; Boyes, Barry

    2016-01-01

    The ability to resolve glycans while attached to tryptic peptides would greatly facilitate glycoproteomics, as this would enable site-specific glycan characterization. Peptide/glycopeptide separations are typically performed using reversed-phase liquid chromatography (RPLC), where retention is driven by hydrophobic interaction. As the hydrophilic glycans do not interact significantly with the RPLC stationary phase, it is difficult to resolve glycopeptides that differ only in their glycan structure, even when these differences are large. Alternatively, glycans interact extensively with the stationary phases used in hydrophilic interaction chromatography (HILIC), and consequently, differences in glycan structure have profound chromatographic shifts in this chromatographic mode. Here, we evaluate HILIC for the separation of isomeric glycopeptide mixtures that have the same peptide backbone but isomeric glycans. Hydrophilic functional groups on both the peptide and the glycan interact with the HILIC stationary phase, and thus, changes to either of these moieties can alter the chromatographic behavior of a glycopeptide. The interactive processes permit glycopeptides to be resolved from each other based on differences in their amino acid sequences and/or their attached glycans. The separations of glycans in HILIC are sufficient to permit resolution of isomeric N-glycan structures, such as sialylated N-glycan isomers differing in α2-3 and α2-6 linkages, while these glycans remain attached to peptides. PMID:27582638

  19. Pharmacodynamics of Glycopeptides in the Mouse Peritonitis Model of Streptococcus pneumoniae or Staphylococcus aureus Infection

    PubMed Central

    Knudsen, Jenny Dahl; Fuursted, Kurt; Raber, Susan; Espersen, Frank; Frimodt-Møller, Niels

    2000-01-01

    The emergence of resistance to various antibiotics in pneumococci leaves the glycopeptides as the only antibiotics against which pneumococci have no resistance mechanism. This situation has led to a renewed interest in the use of glycopeptides. It has not yet been possible to conclude which one or more of the pharmacokinetic or pharmacodynamic (PK/PD) parameters are the most important and best predictors for the effects of treatment with glycopeptides in animal models or in humans. We used the mouse peritonitis model with immunocompetent mice and with Staphylococcus aureus and Streptococcus pneumoniae as infective organisms. A wide spectrum of different treatment regimens with vancomycin and teicoplanin was tested to study the pharmacodynamics of these drugs. In studies in which the single dose that protected 50% of lethally infected mice (ED50) was given as one dose or was divided into two doses, survival was significantly decreased when the dose was divided. The only statistically significant correlations between the percentage of survival of the mice after 6 days and each of the PK/PD parameters were for peak concentration (Cmax)/MIC and S. aureus and for the free fraction of Cmax (Cmax-free)/MIC and S. pneumoniae. For S. pneumoniae, the ED50 for different dosing regimens increased with the number of doses given; e.g., the single-dose ED50s for vancomycin and teicoplanin were 0.65 and 0.45 mg/kg, respectively, but the ED50s for dosing regimens with 2-h doses given for 48 h were 6.79 and 5.67 mg/kg, respectively. In experiments with 39 different vancomycin dosing regimens and 40 different teicoplanin dosing regimens against S. pneumoniae, the different PK/PD parameters were analyzed using logistic regression. The Cmax-free/MIC was one of two parameters that best explained the effect for both drugs; for vancomycin, the other important parameter was the AUC/MIC, and for teicoplanin, the other parameter was the time the free fraction of the drug is above the MIC

  20. Pharmacodynamics of glycopeptides in the mouse peritonitis model of Streptococcus pneumoniae or Staphylococcus aureus infection.

    PubMed

    Knudsen, J D; Fuursted, K; Raber, S; Espersen, F; Frimodt-Moller, N

    2000-05-01

    The emergence of resistance to various antibiotics in pneumococci leaves the glycopeptides as the only antibiotics against which pneumococci have no resistance mechanism. This situation has led to a renewed interest in the use of glycopeptides. It has not yet been possible to conclude which one or more of the pharmacokinetic or pharmacodynamic (PK/PD) parameters are the most important and best predictors for the effects of treatment with glycopeptides in animal models or in humans. We used the mouse peritonitis model with immunocompetent mice and with Staphylococcus aureus and Streptococcus pneumoniae as infective organisms. A wide spectrum of different treatment regimens with vancomycin and teicoplanin was tested to study the pharmacodynamics of these drugs. In studies in which the single dose that protected 50% of lethally infected mice (ED(50)) was given as one dose or was divided into two doses, survival was significantly decreased when the dose was divided. The only statistically significant correlations between the percentage of survival of the mice after 6 days and each of the PK/PD parameters were for peak concentration (C(max))/MIC and S. aureus and for the free fraction of C(max) (C(max-free))/MIC and S. pneumoniae. For S. pneumoniae, the ED(50) for different dosing regimens increased with the number of doses given; e.g., the single-dose ED(50)s for vancomycin and teicoplanin were 0.65 and 0. 45 mg/kg, respectively, but the ED(50)s for dosing regimens with 2-h doses given for 48 h were 6.79 and 5.67 mg/kg, respectively. In experiments with 39 different vancomycin dosing regimens and 40 different teicoplanin dosing regimens against S. pneumoniae, the different PK/PD parameters were analyzed using logistic regression. The C(max-free)/MIC was one of two parameters that best explained the effect for both drugs; for vancomycin, the other important parameter was the AUC/MIC, and for teicoplanin, the other parameter was the time the free fraction of the drug is

  1. High-yield secretion of recombinant proteins expressed in tobacco cell culture with a designer glycopeptide tag: Process development.

    PubMed

    Zhang, Ningning; Gonzalez, Maria; Savary, Brett; Xu, Jianfeng

    2016-03-01

    Low-yield protein production remains the most significant economic hurdle with plant cell culture technology. Fusions of recombinant proteins with hydroxyproline-O-glycosylated designer glycopeptide tags have consistently boosted secreted protein yields. This prompted us to study the process development of this technology aiming to achieve productivity levels necessary for commercial viability. We used a tobacco BY-2 cell culture expressing EGFP as fusion with a glycopeptide tag comprised of 32 repeat of "Ser-Pro" dipeptide, or (SP)32 , to study cell growth and protein secretion, culture scale-up, and establishment of perfusion cultures for continuous production. The BY-2 cells accumulated low levels of cell biomass (∼7.5 g DW/L) in Schenk & Hildebrandt medium, but secreted high yields of (SP)32 -tagged EGFP (125 mg/L). Protein productivity of the cell culture has been stable for 6.0 years. The BY-2 cells cultured in a 5-L bioreactor similarly produced high secreted protein yield at 131 mg/L. Successful operation of a cell perfusion culture for 30 days was achieved under the perfusion rate of 0.25 and 0.5 day(-1) , generating a protein volumetric productivity of 17.6 and 28.9 mg/day/L, respectively. This research demonstrates the great potential of the designer glycopeptide technology for use in commercial production of valuable proteins with plant cell cultures. PMID:26627201

  2. Structural analysis and immunostimulatory activity of glycopeptides from Paecilomyces sinensis.

    PubMed

    Zhu, Zhen-Yuan; Meng, Meng; Sun, Huiqing; Li, Yang; Yu, Na; Zhang, Yong-Min

    2016-03-01

    The parasitic fungus, Paecilomyces sinensis, is used to produce Cordyceps materials as a succedaneum of natural Cordyceps sinensis (C. sinensis) in China. In this work, a glycopeptide (CPS-II) was isolated and purified from Paecilomyces sinensis. The result of HPLC indicated that CPS-II was a glycopeptide. The estimated average molecular weight of CPS-II was 2 × 10(6) Da. FTIR, methylation, periodate oxidation, Smith degradation, (1)H NMR, (13)C NMR and CD were used for its structural analysis. The glycopeptide CPS-II was mainly composed of (1 → 3), (1 → 4) connected glucose and galactose as the backbone, there are (1 → 2,3,6) connected glucose, (1 → 3,6) connected mannose, and (1 → 6) connected galactose. Cell proliferation assay and morphological observations indicated that in a certain range of concentrations and time, CPS-II can significantly improve the proliferation activity of RAW264.7 cells. PMID:26912165

  3. Glycan Side Reaction May Compromise ETD-Based Glycopeptide Identification

    NASA Astrophysics Data System (ADS)

    Darula, Zsuzsanna; Medzihradszky, Katalin F.

    2014-06-01

    Tris(hydroxymethyl)aminomethane (Tris) is one of the most frequently used buffer ingredients. Among other things, it is recommended and is usually used for lectin-based affinity enrichment of glycopeptides. Here we report that sialic acid, a common `capping' unit in both N- and O-linked glycans may react with this chemical, and this side reaction may compromise glycopeptide identification when ETD spectra are the only MS/MS data used in the database search. We show that the modification may alter N- as well as O-linked glycans, the Tris-derivative is still prone to fragmentation both in `beam-type' CID (HCD) and ETD experiments, at the same time—since the acidic carboxyl group was `neutralized'—it will display a different retention time than its unmodified counterpart. We also suggest solutions that—when incorporated into existing search engines—may significantly improve the reliability of glycopeptide assignments.

  4. Bacteria subsisting on antibiotics.

    PubMed

    Dantas, Gautam; Sommer, Morten O A; Oluwasegun, Rantimi D; Church, George M

    2008-04-01

    Antibiotics are a crucial line of defense against bacterial infections. Nevertheless, several antibiotics are natural products of microorganisms that have as yet poorly appreciated ecological roles in the wider environment. We isolated hundreds of soil bacteria with the capacity to grow on antibiotics as a sole carbon source. Of 18 antibiotics tested, representing eight major classes of natural and synthetic origin, 13 to 17 supported the growth of clonal bacteria from each of 11 diverse soils. Bacteria subsisting on antibiotics are surprisingly phylogenetically diverse, and many are closely related to human pathogens. Furthermore, each antibiotic-consuming isolate was resistant to multiple antibiotics at clinically relevant concentrations. This phenomenon suggests that this unappreciated reservoir of antibiotic-resistance determinants can contribute to the increasing levels of multiple antibiotic resistance in pathogenic bacteria. PMID:18388292

  5. Susceptibility of Glycopeptide-Resistant Enterococci to Linezolid, Quinupristin/dalfopristin, Tigecycline and Daptomycin in a Tertiary Greek Hospital.

    PubMed

    Maraki, Sofia; Samonis, George; Dimopoulou, Dimitra; Mantadakis, Elpis

    2014-12-01

    We investigated the antibiotic susceptibility of glycopeptide-resistant enterococci (GRE). Seventy consecutive GRE were tested. Sixty-two isolates were identified as Enterococcus faecium (88.6%), and 8 (11.4%) as Enterococcus faecalis. All strains were susceptible to linezolid and daptomycin, while 17.1% (12/70) and 11.4% (8/70) were resistant to quinupristin/dalfopristin (QD) and tigecycline, respectively. All E. faecalis isolates were resistant to QD, while 4 of 62 (6.5%) E. faecium isolates were resistant to QD. All E. faecalis isolates were susceptible to tigecycline, while 14.5% (9/62) E. faecium isolates were resistant. Continued surveillance of GRE antibiotic susceptibilities is important for combating these multi-resistant nosocomial pathogens. PMID:25566405

  6. Susceptibility of Glycopeptide-Resistant Enterococci to Linezolid, Quinupristin/dalfopristin, Tigecycline and Daptomycin in a Tertiary Greek Hospital

    PubMed Central

    Dimopoulou, Dimitra; Mantadakis, Elpis

    2014-01-01

    We investigated the antibiotic susceptibility of glycopeptide-resistant enterococci (GRE). Seventy consecutive GRE were tested. Sixty-two isolates were identified as Enterococcus faecium (88.6%), and 8 (11.4%) as Enterococcus faecalis. All strains were susceptible to linezolid and daptomycin, while 17.1% (12/70) and 11.4% (8/70) were resistant to quinupristin/dalfopristin (QD) and tigecycline, respectively. All E. faecalis isolates were resistant to QD, while 4 of 62 (6.5%) E. faecium isolates were resistant to QD. All E. faecalis isolates were susceptible to tigecycline, while 14.5% (9/62) E. faecium isolates were resistant. Continued surveillance of GRE antibiotic susceptibilities is important for combating these multi-resistant nosocomial pathogens. PMID:25566405

  7. Antibiotic resistant in microorganisms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antimicrobial agents are necessary for use in veterinary medicine including the production of food producing animals. Antibiotic use is indicated for the treatment of bacterial target organisms and/or disease for which the antibiotic was developed. However, an unintended consequence of antibiotic ...

  8. Antibiotic Resistance

    MedlinePlus

    ... lives. But there is a growing problem of antibiotic resistance. It happens when bacteria change and become able ... resistant to several common antibiotics. To help prevent antibiotic resistance Don't use antibiotics for viruses like colds ...

  9. Alternatives to antibiotics: a symposium on the challenges and solutions for animal production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antibiotics are one of the most important medical discoveries of the 20th century and will remain an essential tool for treating animal and human diseases in the 21st century. However, antibiotic resistance among bacterial pathogens and concerns over their prudent use in animals has garnered global...

  10. Luminamicin, a new antibiotic. Production, isolation and physico-chemical and biological properties.

    PubMed

    Omura, S; Iwata, R; Iwai, Y; Taga, S; Tanaka, Y; Tomoda, H

    1985-10-01

    A new antibiotic, luminamicin, was isolated from the culture broth of an actinomycete strain OMR-59. It exhibits antibacterial activity against anaerobic bacteria, especially against Clostridium sp. The molecular formula of the antibiotic was determined as C32H38O12 on the basis of high resolution mass spectrum, elemental analysis and NMR spectrum. PMID:3840790

  11. Antibiotic production by Pseudomonas: Insights into biosynthesis, diversity, and environmental consequences.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Our current understanding of the biochemistry and environmental consequences of antibiotic biosynthesis by Pseudomonas is derived largely from studies of root-associated strains inhibitory to plant pathogens. Such strains often produce one or more antibiotics including pyoluteorin, pyrrolnitrin, 2,4...

  12. Effects of returning NF concentrate on the MBR-NF process treating antibiotic production wastewater.

    PubMed

    Li, Kun; Cheng, Yutao; Wang, Jianxing; Zhang, Junya; Liu, Jibao; Yu, Dawei; Li, Mingyue; Wei, Yuansong

    2016-07-01

    The optimization of the nanofiltration (NF) concentrate backflow ratio (R cb) and the influence of the NF concentrate on the performance of membrane bioreactor-nanofiltration (MBR-NF) process treating antibiotic production wastewater were investigated on a laboratory scale. The R cb was optimized at 60 % based on the removal rates of chemical oxygen demand (COD) and NH4 (+)-N by MBR. Data analyses indicated that salinity brought by NF concentrate is the major driver leading to the decrease of sludge activity, especially at a high R cb. EPS analysis showed that electric conductivity (EC), proteins in soluble microbial products (SMP), and SMP brought by NF concentrate are the dominant factors causing the severe membrane fouling in MBR. Furthermore, undegradable substances including fulvic acid-like and humic acid-like compounds accumulated in NF concentrate showed significant influence on fouling of NF. MBR could well degrade small MW compounds in NF concentrate, which confirmed the enhancement of organic removal efficiency by recycling the NF concentrate to MBR. The MBR-NF process showed a relatively stable performance at the R cb of 60 % (volume reduction factor (VRF) = 5), and the NF permeate could satisfy the water quality standard for fermentation process with a water recovery rate of 90.9 %. PMID:27000117

  13. Effect of retS gene on antibiotics production in Pseudomonas fluorescens FD6.

    PubMed

    Zhang, Qingxia; Xiao, Qi; Xu, Jingyou; Tong, Yunhui; Wen, Jia; Chen, Xijun; Wei, Lihui

    2015-11-01

    A hybrid sensor kinase termed RetS (regulator of exopolysaccharide and Type III secretion) controls expression of numerous genes in Pseudomonas aeruginosa. To investigate the function of RetS in P. fluorescens FD6, the retS gene was disrupted. Genetic inactivation of retS resulted in enhanced production of 2, 4-diacetylphloroglucinol, pyrrolnitrin, and pyoluteorin. The retS mutant also exhibited significant increase in phlA-lacZ, prnA-lacZ, and pltA-lacZ transcription levels, influencing expression levels of the small regulatory RNAs RsmX and RsmZ. In the gacSretS double mutant, all the phenotypic changes caused by the retS deletion were reversed to the level of gacS single mutant. Furthermore, the retS mutation drastically elevated biofilm formation and improved the colonization ability of strain FD6 on wheat rhizospheres. Based on these results, we proposed that RetS negatively controlled the production of antibiotics through the Gac/Rsm pathway in P. fluorescens FD6. PMID:26505308

  14. Enhanced antibiotic production by Streptomyces sindenensis using artificial neural networks coupled with genetic algorithm and Nelder-Mead downhill simplex.

    PubMed

    Tripathi, C K M; Khan, Mahvish; Praveen, Vandana; Khan, Saif; Srivastava, Akanksha

    2012-07-01

    Antibiotic production with Streptomyces sindenensis MTCC 8122 was optimized under submerged fermentation conditions by artificial neural network (ANN) coupled with genetic algorithm (GA) and Nelder-Mead downhill simplex (NMDS). Feed forward back-propagation ANN was trained to establish the mathematical relationship among the medium components and length of incubation period for achieving maximum antibiotic yield. The optimization strategy involved growing the culture with varying concentrations of various medium components for different incubation periods. Under non-optimized condition, antibiotic production was found to be 95 microgram/ml, which nearly doubled (176 microgram/ml) with the ANN-GA optimization. ANN-NMDS optimization was found to be more efficacious, and maximum antibiotic production (197 microgram/ml) was obtained by cultivating the cells with (g/l) fructose 2.7602, MgSO4 1.2369, (NH4)2PO4 0.2742, DL-threonine 3.069%, and soyabean meal 1.952%, for 9.8531 days of incubation, which was roughly 12% higher than the yield obtained by ANN coupled with GA under the same conditions. PMID:22580313

  15. Exploring glycopeptide-resistance in Staphylococcus aureus: a combined proteomics and transcriptomics approach for the identification of resistance-related markers

    PubMed Central

    Scherl, Alexander; François, Patrice; Charbonnier, Yvan; Deshusses, Jacques M; Koessler, Thibaud; Huyghe, Antoine; Bento, Manuela; Stahl-Zeng, Jianru; Fischer, Adrien; Masselot, Alexandre; Vaezzadeh, Alireza; Gallé, Francesca; Renzoni, Adriana; Vaudaux, Pierre; Lew, Daniel; Zimmermann-Ivol, Catherine G; Binz, Pierre-Alain; Sanchez, Jean-Charles; Hochstrasser, Denis F; Schrenzel, Jacques

    2006-01-01

    Background To unravel molecular targets involved in glycopeptide resistance, three isogenic strains of Staphylococcus aureus with different susceptibility levels to vancomycin or teicoplanin were subjected to whole-genome microarray-based transcription and quantitative proteomic profiling. Quantitative proteomics performed on membrane extracts showed exquisite inter-experimental reproducibility permitting the identification and relative quantification of >30% of the predicted S. aureus proteome. Results In the absence of antibiotic selection pressure, comparison of stable resistant and susceptible strains revealed 94 differentially expressed genes and 178 proteins. As expected, only partial correlation was obtained between transcriptomic and proteomic results during stationary-phase. Application of massively parallel methods identified one third of the complete proteome, a majority of which was only predicted based on genome sequencing, but never identified to date. Several over-expressed genes represent previously reported targets, while series of genes and proteins possibly involved in the glycopeptide resistance mechanism were discovered here, including regulators, global regulator attenuator, hyper-mutability factor or hypothetical proteins. Gene expression of these markers was confirmed in a collection of genetically unrelated strains showing altered susceptibility to glycopeptides. Conclusion Our proteome and transcriptome analyses have been performed during stationary-phase of growth on isogenic strains showing susceptibility or intermediate level of resistance against glycopeptides. Altered susceptibility had emerged spontaneously after infection with a sensitive parental strain, thus not selected in vitro. This combined analysis allows the identification of hundreds of proteins considered, so far as hypothetical protein. In addition, this study provides not only a global picture of transcription and expression adaptations during a complex antibiotic

  16. [Utilization of mycelial waste of antibiotic production in the technology of kilned construction materials].

    PubMed

    Karpukhin, V F; Krymskiĭ, M V; Ivanov, I A; Makridin, N I; Kalashnikov, V I

    1985-01-01

    At present the main part of the mycelial waste of antibiotic production is collected in sludge lagoones, discarded to the sewage treatment system or burnt. The mycelial waste is one of the causes of the environmental pollution. It contains a significant quantity of valuable substances, such as lipids, carbohydrates, proteins and amino acids. The inorganic portion of the waste includes the compounds of calcium, magnesium, sodium, iron, silicium and phosphorus. The levels of the above substances in the mycelial waste allow using it as organic mineral additives in making expanded clay aggregate gravel with the use of low quality clay and loam. It may be also used as the burn-out of the raw material charge in making burnt bricks and other burnt building materials. By its calorific value the mycelial waste is equal to brown coal or peat. It was shown that the structural and mechanical properties of the mixtures of the mycelium and clay depended on the moisture content of the composition and the proportion of its components. The mycelial waste provided a decrease in the optimal temperature of burning by 40-50 degrees C. The production tests at the expanded clay aggregate plants showed that the bulk weight of expanded clay aggregate might be lowered by 50-100 kg/m3 and the usual additives with the use of petroleum products might be completely excluded from the technological process. The use of the mycelial waste for manufacture of burnt building materials provides saving of the fuel energy sources and improvement of the quality of the finished product. It is also important from the ecological viewpoint. PMID:3994341

  17. Affinity entrapment of oligosaccharides and glycopeptides using free lectin solution.

    PubMed

    Yodoshi, Masahiro; Oyama, Takehiro; Masaki, Ken; Kakehi, Kazuaki; Hayakawa, Takao; Suzuki, Shigeo

    2011-01-01

    Two procedures were proposed for the specific recovery of fluorescent derivatives of glycoprotein-derived oligosaccharides and tryptic glycopeptides using certain plant lectins. The first was based on the salting out of oligosaccharide-lectin conjugates with ammonium sulfate. Oligosaccharides specifically bound to lectins were recovered free from lectins using ethanol precipitation after dissolution in water. This method enabled group separation of 2-aminopyridine-labeled oligosaccharides derived from ovalbumin to galacto-oligosaccharides and agalacto-oligosaccharides by Ricinus communis agglutinin, and to high mannose- and hybrid-type oligosaccharides by wheat-germ agglutinin. Fractional precipitation based on differences in affinity for concanavalin A was accomplished by adding an appropriate concentration of methyl α-mannoside as an inhibitor. In the second method, tryptic digests of glycoproteins were mixed with a lectin solution, and the glycopeptide-lectin conjugates were specifically trapped on a centrifugal ultrafiltration membrane with cut-off of 10 kD. Trapped glycopeptides, as retentates, were passed through membranes by resuspension in diluted acid. This method is particularly useful for the enrichment of glycopeptides in protease digestion mixtures for glycosylation analyses by liquid chromatography-mass spectrometry. PMID:21478615

  18. Stationary phases for the enrichment of glycoproteins and glycopeptides.

    PubMed

    Huang, Bao-Yu; Yang, Chun-Kai; Liu, Ching-Piao; Liu, Chuen-Ying

    2014-08-01

    The analysis of protein glycosylation is important for biomedical and biopharmaceutical research. Recent advances in LC-MS analysis have enabled the identification of glycosylation sites, the characterisation of glycan structures and the identification and quantification of glycoproteins and glycopeptides. However, this type of analysis remains challenging due to the low abundance of glycopeptides in complex protein digests, the microheterogeneity at glycosylation sites, ion suppression effects and the competition for ionisation by co-eluting peptides. Specific sample preparation is necessary for comprehensive and site-specific glycosylation analyses using MS. Therefore, researchers continue to pursue new columns to broaden their applications. The current manuscript covers recent literature published from 2008 to 2013. The stationary phases containing various chemical bonding methods or ligands immobilisation strategies on solid supports that selectively enrich N-linked or sialylated N-glycopeptides are categorised with either physical or chemical modes of binding. These categories include lectin affinity, hydrophilic interactions, boronate affinity, titanium dioxide affinity, hydrazide chemistry and other separation techniques. This review should aid in better understanding the syntheses and physicochemical properties of each type of stationary phases for enriching glycoproteins and glycopeptides. PMID:24729282

  19. Eubacterial Diterpene Cyclase Genes Essential for Production of the Isoprenoid Antibiotic Terpentecin

    PubMed Central

    Dairi, Tohru; Hamano, Yoshimitsu; Kuzuyama, Tomohisa; Itoh, Nobuya; Furihata, Kazuo; Seto, Haruo

    2001-01-01

    A gene cluster containing the mevalonate pathway genes (open reading frame 2 [ORF2] to ORF7) for the formation of isopentenyl diphosphate and a geranylgeranyl diphosphate (GGDP) synthase gene (ORF1) had previously been cloned from Streptomyces griseolosporeus strain MF730-N6, a diterpenoid antibiotic, terpentecin (TP) producer (Y. Hamano, T. Dairi, M. Yamamoto, T. Kawasaki, K Kaneda, T. Kuzuyama, N. Itoh, and H. Seto, Biosci. Biotech. Biochem. 65:1627–1635, 2001). Sequence analysis in the upstream region of the cluster revealed seven new ORFs, ORF8 to ORF14, which were suggested to encode TP biosynthetic genes. We constructed two mutants, in which ORF11 and ORF12, which encode a protein showing similarities to eukaryotic diterpene cyclases (DCs) and a eubacterial pentalenene synthase, respectively, were inactivated by gene disruptions. The mutants produced no TP, confirming that these cyclase genes are essential for the production of TP. The two cyclase genes were also expressed in Streptomyces lividans together with the GGDP synthase gene under the control of the ermE* constitutive promoter. The transformant produced a novel cyclic diterpenoid, ent-clerod-3,13(16),14-triene (terpentetriene), which has the same basic skeleton as TP. The two enzymes, each of which was overproduced in Escherichia coli and purified to homogeneity, converted GGDP into terpentetriene. To the best of our knowledge, this is the first report of a eubacterial DC. PMID:11567009

  20. A comparison of the effects of different yeast products and antibiotic on broiler performance.

    PubMed

    Owens, B; McCracken, K J

    2007-02-01

    1. The objectives of this experiment were to compare the effects of different yeast products, with different nucleotide contents and inclusion rates, on broiler performance and to compare the effects to those observed with an antibiotic growth promoter. 2. Two experiments were carried out over two time replicates, one in individual wire cages and one in group pens. 3. Birds were given a diet based on a commercial formulation, which was split into 7 batches. One batch (C) contained no growth promoter and acted as a negative control, another (AV) contained the antibiotic growth promoter Avilomycin (5 g/tonne) and acted as the positive control. The other batches contained yeast extract 2012 at 100 g/tonne (Y21), yeast extract 2012 at 500 g/tonne (Y25), standard yeast 18 at 100 g/tonne (Y81), standard yeast 18 enriched in nucleotides at 100 g/tonne (Y8N1) and standard yeast 18 enriched in nucleotides at 500 g/tonne (Y8N5). 4. In the penned experiment, 280 Cobb broiler chicks (40 birds/treatment) were randomised to diet and pen position on day of hatch. Birds were fed ad libitum until slaughter at 28 d. Bird performance was monitored during the experimental period. 5. In the individual cage experiment, 63 Cobb broiler chicks (9 birds/treatment) were taken from the pens at 7 d of age and randomised to diet and cage position. Birds were fed ad libitum from d 7 to d 28. A 7-d excreta collection was carried out to determine apparent metabolisable energy (AME) content and nutrient digestibility between d 14 and d 21. Bird intake and weight were monitored weekly during the experimental period. At 28 d the birds were killed and viscosity of jejunal digesta supernatant was determined. 6. In the penned experiment, diet had no significant effect on dry matter intake (DMI), live weight gain (LWG) or gain:feed values during any individual week of the experiment or for the entire experimental period. In the caged experiment, DMI was numerically highest for birds fed Y25 diet over

  1. The posttranslocational chaperone lipoprotein PrsA is involved in both glycopeptide and oxacillin resistance in Staphylococcus aureus.

    PubMed

    Jousselin, Ambre; Renzoni, Adriana; Andrey, Diego O; Monod, Antoinette; Lew, Daniel P; Kelley, William L

    2012-07-01

    Understanding in detail the factors which permit Staphylococcus aureus to counteract cell wall-active antibiotics is a prerequisite to elaborating effective strategies to prolong the usefulness of these drugs and define new targets for pharmacological intervention. Methicillin-resistant S. aureus (MRSA) strains are major pathogens of hospital-acquired and community-acquired infections and are most often treated with glycopeptides (vancomycin and teicoplanin) because of their resistance to most penicillins and a limited arsenal of clinically proven alternatives. In this study, we examined PrsA, a lipid-anchored protein of the parvulin PPIase family (peptidyl-prolyl cis/trans isomerase) found ubiquitously in all Gram-positive species, in which it assists posttranslocational folding at the outer surface of the cytoplasmic membrane. We show by both genetic and biochemical assays that prsA is directly regulated by the VraRS two-component sentinel system of cell wall stress. Disruption of prsA is tolerated by S. aureus, and its loss results in no detectable overt macroscopic changes in cell wall architecture or growth rate under nonstressed growth conditions. Disruption of prsA leads, however, to notable alterations in the sensitivity to glycopeptides and dramatically decreases the resistance of COL (MRSA) to oxacillin. Quantitative transcriptional analysis reveals that prsA and vraR are coordinately upregulated in a panel of stable laboratory and clinical glycopeptide-intermediate S. aureus (GISA) strains compared to their susceptible parents. Collectively, our results point to a role for prsA as a facultative facilitator of protein secretion or extracellular folding and provide a framework for understanding why prsA is a key element of the VraRS-mediated cell wall stress response. PMID:22526301

  2. Acquired Genetic Mechanisms of a Multiresistant Bacterium Isolated from a Treatment Plant Receiving Wastewater from Antibiotic Production

    PubMed Central

    Johnning, Anna; Moore, Edward R. B.; Svensson-Stadler, Liselott; Shouche, Yogesh S.; Larsson, D. G. Joakim

    2013-01-01

    The external environment, particularly wastewater treatment plants (WWTPs), where environmental bacteria meet human commensals and pathogens in large numbers, has been highlighted as a potential breeding ground for antibiotic resistance. We have isolated the extensively drug-resistant Ochrobactrum intermedium CCUG 57381 from an Indian WWTP receiving industrial wastewater from pharmaceutical production contaminated with high levels of quinolones. Antibiotic susceptibility testing against 47 antibiotics showed that the strain was 4 to >500 times more resistant to sulfonamides, quinolones, tetracyclines, macrolides, and the aminoglycoside streptomycin than the type strain O. intermedium LMG 3301T. Whole-genome sequencing identified mutations in the Indian strain causing amino acid substitutions in the target enzymes of quinolones. We also characterized three acquired regions containing resistance genes to sulfonamides (sul1), tetracyclines [tet(G) and tetR], and chloramphenicol/florfenicol (floR). Furthermore, the Indian strain harbored acquired mechanisms for horizontal gene transfer, including a type I mating pair-forming system (MPFI), a MOBP relaxase, and insertion sequence transposons. Our results highlight that WWTPs serving antibiotic manufacturing may provide nearly ideal conditions for the recruitment of resistance genes into human commensal and pathogenic bacteria. PMID:24038701

  3. Cloning of the Staphylococcus aureus ddh gene encoding NAD+-dependent D-lactate dehydrogenase and insertional inactivation in a glycopeptide-resistant isolate.

    PubMed Central

    Boyle-Vavra, S; de Jonge, B L; Ebert, C C; Daum, R S

    1997-01-01

    The mechanism of low-level glycopeptide resistance among staphylococci is not known. A cytoplasmic protein, provisionally called Ddh (W. M. Milewski, S. Boyle-Vavra, B. Moreira, C. C. Ebert, and R. S. Daum, Antimicrob. Agents Chemother. 40:166-172, 1996), and the RNA transcript that contains the ddh gene, which encodes Ddh, are present in increased amounts in a vancomycin-resistant isolate, 523k, compared with the susceptible parent isolate, 523. Sequence analysis had previously revealed that Ddh is related to NAD+-dependent D-lactate dehydrogenase (D-nLDH) and VanH. This latter protein is essential for high-level glycopeptide resistance in Enterococcus faecium and Enterococcus faecalis by synthesizing the D-lactate needed for biosynthesis of D-lactate-terminating peptidoglycan precursors with low affinity for vancomycin. We now provide the direct evidence that the ddh gene product is Staphylococcus aureus D-nLDH and hereafter refer to the protein as D-nLDH. However, overproduction of this protein in isolate 523k did not result in production of D-lactate-containing peptidoglycan precursors, and susceptibility testing of ddh mutants of 523k demonstrated that S. aureus D-nLDH is not necessary for glycopeptide resistance in this isolate. We conclude that the mechanism of glycopeptide resistance in this isolate is distinct from that in enterococci. PMID:9352927

  4. Design and Synthesis of Multifunctional Gold Nanoparticles Bearing Tumor-Associated Glycopeptide Antigens as Potential Cancer Vaccines

    PubMed Central

    Brinas, Raymond P.; Sundgren, Andreas; Sahoo, Padmini; Morey, Susan; Rittenhouse-Olson, Kate; Wilding, Greg E.; Deng, Wei; Barchi, Joseph J

    2012-01-01

    The development of vaccines against specific types of cancers will offer new modalities for therapeutic intervention. Here we describe the synthesis of a novel vaccine construction prepared from spherical gold nanoparticles of 3–5 nm core diameters. The particles were coated with both the tumor-associated glycopeptides antigens containing the cell-surface mucin MUC4 with Thomsen Friedenreich (TF) antigen attached at different sites and a 28-residue peptide from the complement derived protein C3d to act as a B-cell activating “molecular adjuvant”. The synthesis entailed solid phase glycopeptide synthesis, design of appropriate linkers and attachment chemistry of the various molecules to the particles. Attachment to the gold surface was mediated by a novel thiol-containing 33 atom linker which was further modified to be included as a third “spacer” component in the synthesis of several three-component vaccine platforms. Groups of mice were vaccinated either with one of the nanoplatform constructs or with control particles without antigen coating. Evaluation of sera from the immunized animals in enzyme immunoassays (EIA) against each glycopeptide antigen showed a small but statistically significant immune response with production of both IgM and IgG isotypes. Vaccines with one carbohydrate antigen (B, C and E) gave more robust responses than the one with two contiguous disaccharides (D), and vaccine E with a TF antigen attached to threonine at the 10th position of the peptide was selected for IgG over IgM suggesting isotype switching. The data suggested that this platform may be a viable delivery system for tumor-associated glycopeptide antigens. PMID:22812418

  5. Overproduction and identification of butyrolactones SCB1-8 in the antibiotic production superhost Streptomyces M1152.

    PubMed

    Sidda, John D; Poon, Vincent; Song, Lijiang; Wang, Weishan; Yang, Keqian; Corre, Christophe

    2016-07-01

    Gamma-butyrolactones (GBLs) are signalling molecules that control antibiotic production in Streptomyces bacteria. The genetically engineered strain S. coelicolor M1152 was found to overproduce GBLs SCB1-3 as well as five novel GBLs named SCB4-8. Incorporation experiments using isotopically-labelled precursors confirmed the chemical structures of SCB1-3 and established those of SCB4-8. PMID:27180870

  6. Isolation of N-linked glycopeptides by hydrazine-functionalized magnetic particles.

    PubMed

    Sun, Shisheng; Yang, Ganglong; Wang, Ting; Wang, Qinzhe; Chen, Chao; Li, Zheng

    2010-04-01

    We introduce a novel combination of magnetic particles with hydrazine chemistry, dubbed as hydrazine-functionalized magnetic particles (HFMP) for isolation of glycopeptides. Four methods have been developed and compared for the production of HFMP by hydrazine modification of the surface of the carboxyl and epoxy-silanized magnetic particles, respectively. The evaluation of the capability and specificity of HFMP as well as the optimization of the coupling condition for capturing of glycoproteins were systematically investigated. The results showed that HFMP prepared by adipic dihydrazide functionalization from carboxyl-silanized magnetic particles (HFCA) displayed the maximum capture capacity and isolated efficiency for glycoprotein. When measured with glycoproteins, the capacity of the HFCA (1 g) for coupling bovine fetuin was 130 +/- 5.3 mg. The capability of this method was also confirmed by successful isolation of all formerly glycosylated peptides from standard glycoproteins and identification of their glycosylation sites, which demonstrated the feasibility of the HFCA as an alternative solid support for isolation of glycoproteins/glycopeptides. PMID:20169334

  7. Degradation of 2,4-dichlorophenoxyacetic acid by a halotolerant strain of Penicillium chrysogenum: antibiotic production.

    PubMed

    Ferreira-Guedes, Sumaya; Mendes, Benilde; Leitão, Ana Lúcia

    2012-01-01

    The extensive use of pesticides in agriculture has prompted intensive research on chemical and biological methods in order to protect contamination of water and soil resources. In this paper the degradation of the pesticide 2,4-dichlorophenoxyacetic acid by a Penicillium chrysogenum strain previously isolated from a salt mine was studied in batch cultures. Co-degradation of 2,4-dichlorophenoxyacetic acid with additives such as sugar and intermediates of pesticide metabolism was also investigated. Penicillium chrysogenum in solid medium was able to grow at concentrations up to 1000 mg/L of 2,4-dichlorophenoxyacetic acid (2,4-D) with sucrose. Meanwhile, supplementation of the solid medium with glucose and lactose led to fungal growth at concentrations up to 500 mg/L of herbicide. Batch cultures of 2,4-D at 100 mg/L were developed under aerobic conditions with the addition of glucose, lactose and sucrose, showing sucrose as the best additional carbon source. The 2,4-D removal was quantified by liquid chromatography. The fungus was able to use 2,4-D as the sole carbon and energy source under 0%, 2% and 5.9% NaCl. The greatest 2,4-D degradation efficiency was found using alpha-ketoglutarate and ascorbic acid as co-substrates under 2% NaCl at pH 7. Penicillin production was evaluated in submerged cultures by bioassay, and higher amounts of beta-lactam antibiotic were produced when the herbicide was alone. Taking into account the ability of P. chrysogenum CLONA2 to degrade aromatic compounds, this strain could be an interesting tool for 2,4-D herbicide remediation in saline environments. PMID:22629643

  8. Tolerance of staphylococci to bactericidal antibiotics.

    PubMed

    Vaudaux, Pierre; Lew, Daniel P

    2006-05-01

    Antibiotic therapy for deep-seated staphylococcal infections, especially when they are associated with artificial devices used for orthopedic surgery is often associated with failure. Standard anti-staphylococcal bactericidal antibiotics, such as semi-synthetic penicillins, cephalosporins, or glycopeptides, are effective when given prophylactically in clinical conditions or experimental trials of implant-related infections. However, the efficacy of all anti-staphylococcal agents is seriously diminished on already established implant-related deep-seated infections, which then frequently require surgical implant removal to obtain a cure. The failure of antibiotic therapy to cure established staphylococcal foreign-body infections may arise in part from a broad-spectrum phenotypic tolerance expressed in vivo to different classes of antimicrobial agents. The molecular and physiological mechanisms of this in vivo tolerance remain poorly understood. PMID:16651066

  9. In-Depth Characterization and Spectral Library Building of Glycopeptides in the Tryptic Digest of a Monoclonal Antibody Using 1D and 2D LC-MS/MS.

    PubMed

    Dong, Qian; Yan, Xinjian; Liang, Yuxue; Stein, Stephen E

    2016-05-01

    This work presents a detailed analysis of glycopeptides produced in the tryptic digestion of an IgG1 reference material. Analysis was done by nanospray ESI LC-MS/MS over a wide range of HCD collision energies with both conventional 1D separation for various digestion conditions and a 20 fraction 2D-LC study of a single digest. An extended version of NIST-developed software for analysis of "shotgun" proteomics served to identify the glycopeptides from their precursor masses and product ions for peptides with up to three missed cleavages. A peptide with a single missed cleavage, TKPREEQYNSTYR, was dominant and led to the determination of almost all glycans reported in this study. The 2D studies found a total of 247 glycopeptide ions and 60 glycans of different masses, including 30 glycans found in the 1D studies. This significantly larger number of glycans than found in any other glycoanalysis of therapeutic glycoproteins is due to both the improved separation of sialylated versus asialylated species in the first (high-pH) dimension and the ability to inject large amounts of glycosylated peptides in the 2D studies. Systematic variations in retention with glycan size were also noted. Energy-dependent changes in HCD fragmentation confirmed the proposed glycan structures and led to a peak-annotated mass spectral library to aid the analysis of glycopeptides derived from IgG1 drugs. PMID:26990841

  10. pGlyco: a pipeline for the identification of intact N-glycopeptides by using HCD- and CID-MS/MS and MS3

    PubMed Central

    Zeng, Wen-Feng; Liu, Ming-Qi; Zhang, Yang; Wu, Jian-Qiang; Fang, Pan; Peng, Chao; Nie, Aiying; Yan, Guoquan; Cao, Weiqian; Liu, Chao; Chi, Hao; Sun, Rui-Xiang; Wong, Catherine C. L.; He, Si-Min; Yang, Pengyuan

    2016-01-01

    Confident characterization of the microheterogeneity of protein glycosylation through identification of intact glycopeptides remains one of the toughest analytical challenges for glycoproteomics. Recently proposed mass spectrometry (MS)-based methods still have some defects such as lack of the false discovery rate (FDR) analysis for the glycan identification and lack of sufficient fragmentation information for the peptide identification. Here we proposed pGlyco, a novel pipeline for the identification of intact glycopeptides by using complementary MS techniques: 1) HCD-MS/MS followed by product-dependent CID-MS/MS was used to provide complementary fragments to identify the glycans, and a novel target-decoy method was developed to estimate the false discovery rate of the glycan identification; 2) data-dependent acquisition of MS3 for some most intense peaks of HCD-MS/MS was used to provide fragments to identify the peptide backbones. By integrating HCD-MS/MS, CID-MS/MS and MS3, intact glycopeptides could be confidently identified. With pGlyco, a standard glycoprotein mixture was analyzed in the Orbitrap Fusion, and 309 non-redundant intact glycopeptides were identified with detailed spectral information of both glycans and peptides. PMID:27139140

  11. Production and biological activities of a new antifungal antibiotic, TAN-950 A.

    PubMed

    Hakoda, S; Tsubotani, S; Iwasa, T; Suzuki, M; Kondo, M; Harada, S

    1992-06-01

    A novel antifungal antibiotic, TAN-950 complex, was isolated from the culture filtrate of Streptomyces platensis A-136 (IFO 14603, FERM BP-1786). The water-soluble amphoteric substances in this complex were purified by chromatography using ion-exchange resins, QAE-Sephadex and adsorptive resins and were designated TAN-950 A and TAN-950 A-E mixture. The molecular formula of TAN-950 A was determined to be C6H7N2O4Na for the sodium salt. This new amino acid antibiotic showed antifungal activity against Candida albicans in vitro and in vivo, and had low toxicity in mice. PMID:1500350

  12. SweetNET: A Bioinformatics Workflow for Glycopeptide MS/MS Spectral Analysis.

    PubMed

    Nasir, Waqas; Toledo, Alejandro Gomez; Noborn, Fredrik; Nilsson, Jonas; Wang, Mingxun; Bandeira, Nuno; Larson, Göran

    2016-08-01

    Glycoproteomics has rapidly become an independent analytical platform bridging the fields of glycomics and proteomics to address site-specific protein glycosylation and its impact in biology. Current glycopeptide characterization relies on time-consuming manual interpretations and demands high levels of personal expertise. Efficient data interpretation constitutes one of the major challenges to be overcome before true high-throughput glycopeptide analysis can be achieved. The development of new glyco-related bioinformatics tools is thus of crucial importance to fulfill this goal. Here we present SweetNET: a data-oriented bioinformatics workflow for efficient analysis of hundreds of thousands of glycopeptide MS/MS-spectra. We have analyzed MS data sets from two separate glycopeptide enrichment protocols targeting sialylated glycopeptides and chondroitin sulfate linkage region glycopeptides, respectively. Molecular networking was performed to organize the glycopeptide MS/MS data based on spectral similarities. The combination of spectral clustering, oxonium ion intensity profiles, and precursor ion m/z shift distributions provided typical signatures for the initial assignment of different N-, O- and CS-glycopeptide classes and their respective glycoforms. These signatures were further used to guide database searches leading to the identification and validation of a large number of glycopeptide variants including novel deoxyhexose (fucose) modifications in the linkage region of chondroitin sulfate proteoglycans. PMID:27399812

  13. Age-associated glycopeptide pigment in human costal cartilage.

    PubMed Central

    van der Korst, J. K.; Willekens, F. L.; Lansink, A. G.; Henrichs, A. M.

    1977-01-01

    Age-associated pigmentation of human costal cartilage is caused by the accumulation of a brown water-soluble substance which can be only be extracted after proteolytic disruption of the cartilage. After isolation by gel filtration and ion exchange chromatography, the compound was identified as an acid glycopeptide. In contrast to ochronotic pigment and an artificial pigment derived by oxidation of homogentistic acid in alkaline solution, the age-associated cartilage pigment was strongly fluorescent and did not form insoluble complexes with cetylpyridinium chloride. Moreover, age-associated cartilage pigment is alkali resistant, in contrast to the ochronotic pigment. The pigment differs from lipofuscin in being strongly hydrophilic and having no affinity for fat stains. The unidentified chromophore could not be separated from the glycopeptide molecule. PMID:596418

  14. A Regulatory Gene SCO2140 is Involved in Antibiotic Production and Morphological Differentiation of Streptomyces coelicolor A3(2).

    PubMed

    Yu, Lingjun; Pan, Yuanyuan; Liu, Gang

    2016-08-01

    Streptomyces coelicolor is the soil-dwelling bacterium with a complex life cycle and a strong ability to produce plenty of secondary metabolites which are strictly regulated by a variety of regulators. Amino acid alignment shows that the deduced protein of SCO2140 belongs to the family of Leucine-responsive regulatory proteins (Lrps). Disruption of SCO2140 significantly decreased the yields of actinorhodin and calcium-dependent antibiotics, and the complemented strain restored the antibiotic productions to the wild-type level. In contrast, overexpression of SCO2140 increased the actinorhodin production. In agreement with it, the transcriptions of actII-ORF4 and cdaR remarkably reduced in the SCO2140 disruption mutant. The aerial mycelium formation of the SCO2140 disruption mutant was clearly delayed in R2YE medium due to the decrease of ramS expression while its complemented strain could restore the normal formation of aerial mycelia. These results indicated that SCO2140 was involved in antibiotic biosynthesis and morphological differentiation of Streptomyces coelicolor A3(2). PMID:27113590

  15. Variability of antibiotic susceptibility and toxin production of Staphylococcus aureus strains isolated from skin, soft tissue, and bone related infections

    PubMed Central

    2013-01-01

    Background Staphylococcus aureus is an opportunistic commensal bacterium that mostly colonizes the skin and soft tissues. The pathogenicity of S. aureus is due to both its ability to resist antibiotics, and the production of toxins. Here, we characterize a group of genes responsible for toxin production and antibiotic resistance of S. aureus strains isolated from skin, soft tissue, and bone related infections. Results A total of 136 S. aureus strains were collected from five different types of infection: furuncles, pyomyositis, abscesses, Buruli ulcers, and osteomyelitis, from hospital admissions and out-patients in Benin. All strains were resistant to benzyl penicillin, while 25% were resistant to methicillin, and all showed sensitivity to vancomycin. Panton-Valentine leukocidin (PVL) was the most commonly produced virulence factor (70%), followed by staphylococcal enterotoxin B (44%). Exfoliative toxin B was produced by 1.3% of the strains, and was only found in isolates from Buruli ulcers. The tsst-1, sec, and seh genes were rarely detected (≤1%). Conclusions This study provides new insight into the prevalence of toxin and antibiotic resistance genes in S. aureus strains responsible for skin, soft tissue, and bone infections. Our results showed that PVL was strongly associated with pyomyositis and osteomyelitis, and that there is a high prevalence of PVL-MRSA skin infections in Benin. PMID:23924370

  16. Performance and fate of organics in a pilot MBR-NF for treating antibiotic production wastewater with recycling NF concentrate.

    PubMed

    Wang, Jianxing; Li, Kun; Wei, Yuansong; Cheng, Yutao; Wei, Dongbin; Li, Mingyue

    2015-02-01

    A double membrane system comprising a membrane bioreactor (MBR) combined with a nanofiltration (NF) membrane was investigated on a pilot scale for the treatment of antibiotic production wastewater over a three-month period at a pharmaceutical company in Wuxi, China. By recycling the NF concentrate, the combined MBR-NF process was shown to be effective for the treatment of antibiotic production wastewater, resulting in excellent water quality and a high water yield of 92±5.6%. The water quality of the pilot-scale MBR-NF process was excellent; e.g., the concentrations of TOC, NH4(+)-N, TP were stable at 5.52, 0.68, 0.34 mg L(-1), respectively, and the values of turbidity and conductivity of the NF permeate were 0.15 NTU and 2.5 mS cm(-1), respectively; these values meet China's water quality standard requirements for industrial use (GB21903-2008). Not only were the antibiotic removal rates of spiramycin (SPM) and new spiramycin (NSPM) over 95%, the acute toxicity was also drastically reduced by the MBR-NF pilot system. The main organics in the MBR effluent were proteins, polysaccharides, and humic-like substances; they were almost completely retained by the NF membrane and further biodegraded in the MBR because the NF concentrate was recycled. The microbial community of the MBR did not significantly change with the recycling of the NF concentrate. PMID:25475971

  17. Deciphering the Regulon of Streptomyces coelicolor AbrC3, a Positive Response Regulator of Antibiotic Production

    PubMed Central

    Rico, Sergio; Santamaría, Ramón I.; Yepes, Ana; Rodríguez, Héctor; Laing, Emma; Bucca, Giselda; Smith, Colin P.

    2014-01-01

    The atypical two-component system (TCS) AbrC1/C2/C3 (encoded by SCO4598, SCO4597, and SCO4596), comprising two histidine kinases (HKs) and a response regulator (RR), is crucial for antibiotic production in Streptomyces coelicolor and for morphological differentiation under certain nutritional conditions. In this study, we demonstrate that deletion of the RR-encoding gene, abrC3 (SCO4596), results in a dramatic decrease in actinorhodin (ACT) and undecylprodiginine (RED) production and delays morphological development. In contrast, the overexpression of abrC3 in the parent strain leads to a 33% increase in ACT production in liquid medium. Transcriptomic analysis and chromatin immunoprecipitation with microarray technology (ChIP-chip) analysis of the ΔabrC3 mutant and the parent strain revealed that AbrC3 directly controls ACT production by binding to the actII-ORF4 promoter region; this was independently verified by in vitro DNA-binding assays. This binding is dependent on the sequence 5′-GAASGSGRMS-3′. In contrast, the regulation of RED production is not due to direct binding of AbrC3 to either the redZ or redD promoter region. This study also revealed other members of the AbrC3 regulon: AbrC3 is a positive autoregulator which also binds to the promoter regions of SCO0736, bdtA (SCO3328), absR1 (SCO6992), and SCO6809. The direct targets share the 10-base consensus binding sequence and may be responsible for some of the phenotypes of the ΔabrC3 mutant. The identification of the AbrC3 regulon as part of the complex regulatory network governing antibiotic production widens our knowledge regarding TCS involvement in control of antibiotic synthesis and may contribute to the rational design of new hyperproducer host strains through genetic manipulation of such systems. PMID:24509929

  18. Replacement for antibiotics: Lysozyme

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antibiotics have been fed at subtherapeutic levels to swine as growth promoters for more than 60 years, and the majority of swine produced in the U.S. receive antibiotics in their feed at some point in their production cycle. These compounds benefit the producers by minimizing production losses by ...

  19. Advanced oxidation of the antibiotic sulfapyridine by UV/H₂O₂: Characterization of its transformation products and ecotoxicological implications.

    PubMed

    García-Galán, Ma Jesús; Anfruns, Alba; Gonzalez-Olmos, Rafael; Rodriguez-Mozaz, Sara; Comas, Joaquim

    2016-03-01

    The aim of the present work is to investigate, under lab-scale conditions, the removal and transformation of the antibiotic sulfapyridine (SPY) upon advanced oxidation with UV/H2O2. High resolution mass spectrometry (HRMS) analyses by means of an ultra-high pressure liquid chromatography (UHPLC)-linear ion trap high resolution Orbitrap instrument (LTQ-Orbitrap-MS) were carried out in order to elucidate the different transformation products (TPs) generated. The abatement (>99%) of the antibiotic was only achieved after 180 min, highlighting its resilience to elimination and its potential persistence in the environment A total of 10 TPs for SPY were detected and their molecular structures elucidated by means of MS(2) and MS(3) scans. Finally, the combined ecotoxicity at different treatment times was evaluated by means of bioluminescence inhibition assays with the marine bacteria Vibrio fischeri. PMID:26789837

  20. Amplification of the housekeeping sigma factor in Pseudomonas fluorescens CHA0 enhances antibiotic production and improves biocontrol abilities.

    PubMed Central

    Schnider, U; Keel, C; Blumer, C; Troxler, J; Défago, G; Haas, D

    1995-01-01

    Pseudomonas fluorescens CHA0 produces a variety of secondary metabolites, in particular the antibiotics pyoluteorin and 2,4-diacetylphloroglucinol, and protects various plants from diseases caused by soilborne pathogenic fungi. The rpoD gene encoding the housekeeping sigma factor sigma 70 of P. fluorescens was sequenced. The deduced RpoD protein showed 83% identity with RpoD of Pseudomonas aeruginosa and 67% identity with RpoD of Escherichia coli. Attempts to inactivate the single chromosomal rpoD gene of strain CHA0 were unsuccessful, indicating an essential role of this gene. When rpoD was carried by an IncP vector in strain CHA0, the production of both antibiotics was increased severalfold and, in parallel, protection of cucumber against disease caused by Pythium ultimum was improved, in comparison with strain CHA0. PMID:7665535

  1. The structure of a glycopeptide purified from porcine thyroglobulin

    PubMed Central

    Fukuda, Minoru; Egami, Fujio

    1971-01-01

    1. The structure of a purified glycopeptide isolated from porcine thyroglobulin was studied by sequential hydrolysis with specific glycosidases, by periodate oxidation and by treatment with galactose oxidase. 2. Sequential hydrolysis with several combinations of neuraminidase, α-l-fucosidase, β-d-galactosidase, β-N-acetyl-d-glucosaminidase and α-d-mannosidase presented the evidence for the following structure. 3. The monosaccharide sequence of the peripheral moiety of the heteropolysaccharide chain was sialic acid→galactose→N-acetylglucosamine. Some of the galactose residues were non-reducing end-groups with the sequence galactose→N-acetylglucosamine. 4. After removal of the peripheral moiety composed of sialic acid, fucose, galactose and N-acetylglucosamine, α-mannosidase released 1.4mol of mannose/mol of glycopeptide, indicating that two of the three mannose residues were located between peripheral N-acetylglucosamine and internal N-acetylglucosamine or mannose. 5. Periodate oxidation and sodium borohydride reduction confirmed the results obtained by enzymic degradation and gave information concerning the position of substitution. 6. Based on the results obtained by enzymic hydrolysis and periodate oxidation together with the treatment with galactose oxidase, a structure is proposed for the glycopeptide. PMID:4331180

  2. Alternatives to antibiotics as growth promoters for use in swine production: a review

    PubMed Central

    2013-01-01

    In the past two decades, an intensive amount of research has been focused on the development of alternatives to antibiotics to maintain swine health and performance. The most widely researched alternatives include probiotics, prebiotics, acidifiers, plant extracts and neutraceuticals such as copper and zinc. Since these additives have been more than adequately covered in previous reviews, the focus of this review will be on less traditional alternatives. The potential of antimicrobial peptides, clay minerals, egg yolk antibodies, essential oils, eucalyptus oil-medium chain fatty acids, rare earth elements and recombinant enzymes are discussed. Based on a thorough review of the literature, it is evident that a long and growing list of compounds exist which have been tested for their ability to replace antibiotics as feed additives in diets fed to swine. Unfortunately, the vast majority of these compounds produce inconsistent results and rarely equal antibiotics in their effectiveness. Therefore, it would appear that research is still needed in this area and that the perfect alternative to antibiotics does not yet exist. PMID:24034214

  3. Alternatives to antibiotics as growth promoters for use in swine production: a review.

    PubMed

    Thacker, Philip A

    2013-01-01

    In the past two decades, an intensive amount of research has been focused on the development of alternatives to antibiotics to maintain swine health and performance. The most widely researched alternatives include probiotics, prebiotics, acidifiers, plant extracts and neutraceuticals such as copper and zinc. Since these additives have been more than adequately covered in previous reviews, the focus of this review will be on less traditional alternatives. The potential of antimicrobial peptides, clay minerals, egg yolk antibodies, essential oils, eucalyptus oil-medium chain fatty acids, rare earth elements and recombinant enzymes are discussed. Based on a thorough review of the literature, it is evident that a long and growing list of compounds exist which have been tested for their ability to replace antibiotics as feed additives in diets fed to swine. Unfortunately, the vast majority of these compounds produce inconsistent results and rarely equal antibiotics in their effectiveness. Therefore, it would appear that research is still needed in this area and that the perfect alternative to antibiotics does not yet exist. PMID:24034214

  4. Antibiotics and antibiotic resistance in agroecosystems: State of the science

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This review article proposes a simple causal model depicting relationships involved in dissemination of antibiotics and antibiotic resistance in agroecosystems and potential effects on human health, functioning of natural ecosystems, and agricultural productivity. Available evidence for each causal ...

  5. Efficient enrichment of glycopeptides using metal-organic frameworks by hydrophilic interaction chromatography.

    PubMed

    Ji, Yongsheng; Xiong, Zhichao; Huang, Guang; Liu, Jing; Zhang, Zhang; Liu, Zheyi; Ou, Junjie; Ye, Mingliang; Zou, Hanfa

    2014-10-01

    Selective enrichment of glycopeptides from complicated biological samples is critical for glycoproteomics to obtain the structure and glycosylation information of glycoproteins using mass spectrometry (MS), which still remains a great challenge. Hydrophilic interaction chromatography (HILIC)-based strategies have been proposed for selective isolation of glycopeptides via the interactions between the glycan of glycopeptides and the matrices. However, the application of these methods is limited by the medium selectivity of HILIC matrices. In this study, hydrophilic metal-organic frameworks (MOFs) were fabricated and used as a HILIC matrix. The cross-linked CD-MOFs (LCD-MOFs) were facilely prepared with γ-cyclodextrin as ligand and possessed nano-sized cubic structure, superior hydrophilicity, and bio-compatibility. The LCD-MOFs performance for the selective enrichment of glycopeptides from the complex biological samples were investigated with a digested mixture of human immunoglobulin G (IgG) that was used as standard samples. In the selectivity assessment, the non-glycopeptides causing ion suppression to the glycopeptides were effectively removed, the signal of glycopeptides were enhanced significantly by LCD-MOFs, and twenty glycopeptides were identified with 67 fmol of IgG digest. In addition, the resulting LCD-MOFs demonstrated the lower detection limit (3.3 fmol) with a satisfactory recovery yield (84-103%) for glycopeptide enrichment from a digest of IgG. Furthermore, a promising protocol was developed for the selective enrichment of glycopeptides from mouse liver, and 344 unique N-glycosylation sites that mapped to 290 different glycoproteins were identified in a single MS run. The results clearly demonstrated that when used in a HILIC matrix, LCD-MOFs have great potential for identifying and enriching low-abundant glycopeptides in complex biological samples. PMID:25110774

  6. Antibiotic Resistance

    MedlinePlus

    Antibiotics are medicines that fight bacterial infections. Used properly, they can save lives. But there is a growing problem of antibiotic resistance. It happens when bacteria change and become able to resist the effects of an antibiotic. Using antibiotics can lead to resistance. ...

  7. The sigma factor sigma s affects antibiotic production and biological control activity of Pseudomonas fluorescens Pf-5.

    PubMed

    Sarniguet, A; Kraus, J; Henkels, M D; Muehlchen, A M; Loper, J E

    1995-12-19

    Pseudomonas fluorescens Pf-5, a rhizosphere-inhabiting bacterium that suppresses several soilborne pathogens of plants, produces the antibiotics pyrrolnitrin, pyoluteorin, and 2,4-diacetylphloroglucinol. A gene necessary for pyrrolnitrin production by Pf-5 was identified as rpoS, which encodes the stationary-phase sigma factor sigma s. Several pleiotropic effects of an rpoS mutation in Escherichia coli also were observed in an RpoS- mutant of Pf-5. These included sensitivities of stationary-phase cells to stresses imposed by hydrogen peroxide or high salt concentration. A plasmid containing the cloned wild-type rpoS gene restored pyrrolnitrin production and stress tolerance to the RpoS- mutant of Pf-5. The RpoS- mutant overproduced pyoluteorin and 2,4-diacetyl-phloroglucinol, two antibiotics that inhibit growth of the phytopathogenic fungus Pythium ultimum, and was superior to the wild type in suppression of seedling damping-off of cucumber caused by Pythium ultimum. When inoculated onto cucumber seed at high cell densities, the RpoS- mutant did not survive as well as the wild-type strain on surfaces of developing seedlings. Other stationary-phase-specific phenotypes of Pf-5, such as the production of cyanide and extracellular protease(s) were expressed by the RpoS- mutant, suggesting that sigma s is only one of the sigma factors required for the transcription of genes in stationary-phase cells of P. fluorescens. These results indicate that a sigma factor encoded by rpoS influences antibiotic production, biological control activity, and survival of P. fluorescens on plant surfaces. PMID:8618880

  8. Antibiotic Resistance and Biofilm Production in Staphylococcus epidermidis Strains, Isolated from a Tertiary Care Hospital in Mexico City

    PubMed Central

    Cabrera-Contreras, Roberto; Morelos-Ramírez, Rubén; Galicia-Camacho, Ada Nelly; Meléndez-Herrada, Enrique

    2013-01-01

    Staphylococcus epidermidis strains isolated from nosocomial infections represent a serious problem worldwide. In various Mexican states several reports have shown isolates from hospitals with antibiotic resistance to methicillin. In Mexico City, there is scarce information on staphylococcal infections in hospitals. Here, our research findings are shown in a four-year period study (2006–2010) for Staphylococcus epidermidis strains. Susceptibility and/or resistance to antibiotics in SE strains were assessed by phenotypic and molecular methods as mecA gene by PCR, as well as the correlation with biofilm production for these isolates and the relationship to the infection site. Out of a total of 161 (66%) negative biofilm SE strains, just 103 (64%) SE strains were confirmed as MRSE by PCR to mecA gene. From 84 (34%) positive biofilm SE strains, 76 (91%) were confirmed as MRSE by PCR to mecA gene. Higher percentages of resistance to antibiotics and higher number of resistance markers were found in biofilm-forming clinical strains (9 to 14) than non-biofilm-forming SE strains (3 to 8). These research findings represent a guide to establish infection control programs for this hospital. PMID:23724338

  9. Antibiotic resistance and molecular analysis of Staphylococcus aureus isolated from cow's milk and dairy products in northeast Brazil.

    PubMed

    Silveira-Filho, Vladimir M; Luz, Isabelle S; Campos, Ana Paula F; Silva, Wellington M; Barros, Maria Paloma S; Medeiros, Elizabeth S; Freitas, Manuela F L; Mota, Rinaldo A; Sena, Maria J; Leal-Balbino, Tereza C

    2014-04-01

    This work aimed to assess the clonal distribution among 94 strains of Staphylococcus aureus isolated from cow's milk, raw cheese, and a milking machine in 12 dairy farms in northeast Brazil, by analyzing different typing methods and detecting resistance and toxigenic profiles. For the first time, isolates of this region were assessed simultaneously by the polymorphism of the 3'-end coa gene and 16S-23S rDNA, pulsed-field gel electrophoresis, antibiotic resistance phenotyping, and toxigenic arsenal. Although pulsed-field gel electrophoresis patterns showed a wider variation (discriminatory index 0.83) than the PCR-based methods, the internal transcribed spacer-PCR proved to be a useful and inexpensive procedure for conducting epidemiological surveys of S. aureus on a regional scale. Each dairy farm had its own resistance profile, and in two herds, 63% of the strains were multiresistant, probably due to the indiscriminate use of antibiotics in bovine mastitis treatment. No methicillin-resistant S. aureus strains were detected in this study; however, 93.6% of S. aureus strains harbored variable profiles of staphylococcal enterotoxin genes seg, seh, sei, and sej. Transcriptional analysis revealed that 53.3% of staphylococcal enterotoxin genes actually transcribed, pointing out the food poisoning risk of these dairy products to consumers in the region. Based on the detection of the most prevalent clones in a herd or region, appropriate antibiotic therapy and specific immunization can be used for the treatment and control of staphylococcal mastitis. PMID:24680069

  10. Total Syntheses and Initial Evaluation of [Ψ[C(=S)NH]Tpg4]vancomycin, [Ψ[C(=NH)NH]Tpg4]vancomycin, [Ψ[CH2NH]Tpg4]vancomycin and their (4-Chlorobiphenyl)methyl Derivatives: Synergistic Binding Pocket and Peripheral Modifications for the Glycopeptide Antibiotics

    PubMed Central

    Okano, Akinori; Nakayama, Atsushi; Wu, Kejia; Lindsey, Erick A.; Schammel, Alex W.; Feng, Yiqing; Collins, Karen C.

    2015-01-01

    Full details of studies are disclosed on the total synthesis of binding pocket analogues of vancomycin, bearing the peripheral L-vancosaminyl-1,2-D-glucosyl disaccharide, that contain changes to a key single atom in the residue 4 amide (residue 4 carbonyl O → S, NH, H2) designed to directly address the underlying molecular basis of resistance to vancomycin. Also disclosed are studies piloting the late stage transformations conducted on the synthetically more accessible C-terminus hydroxymethyl aglycon derivatives and full details of the peripheral chlorobiphenyl functionalization of all the binding pocket modified vancomycin analogues designed for dual D-Ala-D-Ala/D-Ala-D-Lac binding are reported. Their collective assessment indicate that combined binding pocket and chlorobiphenyl peripherally modified analogues exhibit a remarkable spectrum of antimicrobial activity (VSSA, MRSA, VanA and VanB VRE) and impressive potencies against both vancomycin-sensitive and vancomycin-resistant bacteria (MICs = 0.06–0.005 μg/mL and 0.5–0.06 μg/mL for the amidine and methylene analogues, respectively) and likely benefit from two independent and synergistic mechanisms of action, only one of which is dependent on D-Ala-D-Ala/D-Ala-D-Lac binding. Such analogues are likely to display especially durable antibiotic activity not prone to rapidly acquired clinical resistance. PMID:25750995

  11. Pumilacidin, a complex of new antiviral antibiotics. Production, isolation, chemical properties, structure and biological activity.

    PubMed

    Naruse, N; Tenmyo, O; Kobaru, S; Kamei, H; Miyaki, T; Konishi, M; Oki, T

    1990-03-01

    New antibiotic pumilacidins A, B, C, D, E, F and G were isolated from the culture broth of a strain of Bacillus pumilus. They are cyclic acylheptapeptide composed of a beta-hydroxy fatty acid, two L-leucine, two D-leucine, L-glutamic acid, L-aspartic acid and L-isoleucine (or L-valine). Pumilacidin components were inhibitory to herpes simplex virus type 1 and H+, K(+)-ATPase and demonstrated antiulcer activity in rat. PMID:2157695

  12. Muraymycin nucleoside-peptide antibiotics: uridine-derived natural products as lead structures for the development of novel antibacterial agents

    PubMed Central

    Wirth, Marius; Niro, Giuliana; Leyerer, Kristin

    2016-01-01

    Summary Muraymycins are a promising class of antimicrobial natural products. These uridine-derived nucleoside-peptide antibiotics inhibit the bacterial membrane protein translocase I (MraY), a key enzyme in the intracellular part of peptidoglycan biosynthesis. This review describes the structures of naturally occurring muraymycins, their mode of action, synthetic access to muraymycins and their analogues, some structure–activity relationship (SAR) studies and first insights into muraymycin biosynthesis. It therefore provides an overview on the current state of research, as well as an outlook on possible future developments in this field. PMID:27340469

  13. Fractionation and analysis of veterinary antibiotics and their related degradation products in agricultural soils and drainage waters following swine manure amendment.

    PubMed

    Solliec, Morgan; Roy-Lachapelle, Audrey; Gasser, Marc-Olivier; Coté, Caroline; Généreux, Mylène; Sauvé, Sébastien

    2016-02-01

    The fate of antimicrobial active compound residues in the environment, and especially antibiotics used in swine husbandry are of particular interest for their potential toxicity and contribution to antibiotic resistance. The presence of relatively high concentrations of bioactive compounds has been reported in agricultural areas but few information is available on their degradation products. Veterinary antibiotics reach terrestrial environments through many routes, including application of swine manure to soils. The objectives of this project were first, to develop an analytical method able to quantify and identify veterinary antibiotics and their degradation products in manure, soil and water samples; and second, to study the distribution of these target compounds in soils and drainage waters. A brief evaluation of their potential toxicity in the environment was also made. In order to achieve these objectives, liquid chromatography coupled to high-resolution mass spectrometry was used for its ability to quantify contaminants with sensitivity and selectivity, and its capacity to identify degradation products. Samples of manure, soil and water came from a long-term experimental site where swine manure containing veterinary antibiotics has been applied for many years. In this study, tetracycline antibiotics were found at several hundred μg L(-1) in the swine manure slurry used for fertilization, several hundred of ng L(-1) in drainage waters and several ng g(-1) in soils, while degradation products were sometimes found at concentrations higher than the parent compounds. PMID:26605832

  14. Comparison of NF membrane fouling and cleaning by two pretreatment strategies for the advanced treatment of antibiotic production wastewater.

    PubMed

    Wang, Jianxing; Li, Kun; Yu, Dawei; Zhang, Junya; Wei, Yuansong; Chen, Meixue; Shan, Baoqing

    2016-01-01

    The nanofiltration (NF) membrane fouling characteristics and cleaning strategies were investigated and compared for treating membrane bioreactor (MBR) effluent and MBR-granular activated carbon (GAC) effluent of an antibiotic production wastewater by DK membrane. Results showed that the fouling of treating MBR effluent was more severe than that of treating MBR-GAC effluent. After filtering for 216 h, the difference of membrane flux decline was obvious between MBR effluent and MBR-GAC effluent, with 14.9% and 10.3% flux decline, respectively. Further study showed that organic fouling is the main NF membrane fouling in the advanced treatment of antibiotic production wastewater for both of the two different effluents. Soluble microbial by-product like and tyrosine-like substances were the dominant components in the foulants, whereas humic-like substances existing in the effluents had little contribution to the NF membrane fouling. A satisfactory efficiency of NF chemical cleaning could be obtained using combination of acid (HCl, pH 2.0-2.5) and alkali (NaOH + 0.3 wt% NaDS, pH 10.0-10.5). The favorable cleaning strategy is acid-alkali for treating the MBR-GAC effluent, while it is alkali-acid for treating the MBR effluent. PMID:27148729

  15. Correlation of penicillinase production with phage type and susceptibility to antibiotics and heavy metals in Staphylococcus aureus.

    PubMed

    Rosdahl, V T; Rosendal, K

    1983-11-01

    One hundred and thirty-nine bacteraemia strains of Staphylococcus aureus, representing different combinations of phage type and susceptibility to antibiotics and to cadmium (Cd), arsenate (As) and mercury (Hg), were investigated for penicillinase production. The determination of enzyme activity in induced and uninduced conditions was performed by iodometric titration. The amount of penicillinase produced could be correlated with phage pattern. Epidemically occurring strains of the 94,96 and the 83A complexes produced the largest amount of penicillinase, whereas strains of the 52,52A,80,81 complex were weaker producers. Group-II and group-III strains produced the smallest amount. Susceptibility to antibiotics and to Cd, As and Hg could not be correlated with enzyme activity, but strains resistant to penicillin plus tetracyclines and strains resistant only to Cd did produce less enzyme than strains with other resistance patterns. The percentage mean values than strains with other resistance patterns. The percentage mean values of extracellularity of the enzyme was highest amongst strains of the 94,96 complex and of type 95. Four strains had constitutive production, one being macro-constitutive and three micro-constitutive. All four strains represented rare combinations of the above properties but were susceptible to fusidic acid. The importance of penicillinase production by epidemically occurring strains is discussed. PMID:6227749

  16. Crystal Structures of the Glycopeptide Sulfotransferase Teg12 in a Complex with the Teicoplanin Aglycone

    SciTech Connect

    Bick, Matthew J.; Banik, Jacob J.; Darst, Seth A.; Brady, Sean F.

    2010-06-25

    The TEG gene cluster, a glycopeptide biosynthetic gene cluster that is predicted to encode the biosynthesis of a polysulfated glycopeptide congener, was recently cloned from DNA extracted directly from desert soil. This predicted glycopeptide gene cluster contains three closely related sulfotransferases (Teg12, -13, and -14) that sulfate teicoplanin-like glycopeptides at three unique sites. Here we report a series of structures: an apo structure of Teg12, Teg12 bound to the desulfated cosubstrate 3{prime}-phosphoadenosine 5{prime}-phosphate, and Teg12 bound to the teicoplanin aglycone. Teg12 appears to undergo a series of significant conformational rearrangements during glycopeptide recruitment, binding, and catalysis. Loop regions that exhibit the most conformational flexibility show the least sequence conservation between TEG sulfotransferases. Site-directed mutagenesis guided by our structural studies confirmed the importance of key catalytic residues as well as the importance of residues found throughout the conformationally flexible loop regions.

  17. Crystal Structures of the Glycopeptide Sulfotransferase Teg12 Complexed with the Teicoplanin Aglycone

    PubMed Central

    Bick, Matthew J.; Banik, Jacob J.; Darst, Seth A.; Brady, Sean F.

    2010-01-01

    The TEG gene cluster, a glycopeptide biosynthetic gene cluster that is predicted to encode the biosynthesis of a polysulfated glycopeptide congener, was recently cloned from DNA extracted directly from desert soil. This predicted glycopeptide gene cluster contains three closely related sulfotransferases (Teg12, 13, and 14) that sulfate teicoplanin-like glycopeptides at three unique sites. Here we report a series of structures including: an apo structure of Teg12, Teg12 bound to the desulfated co-substrate 3'-phosphoadenosine 5'-phosphate and Teg12 bound to the teicoplanin aglycone. Teg12 appears to undergo a series of significant conformational rearrangements during glycopeptide recruitment, binding and catalysis. Loop regions that exhibit the most conformational flexibility show the least sequence conservation between TEG sulfotransferases. Site directed mutagenesis guided by our structural studies confirmed the importance of key catalytic residues as well as the importance of residues found throughout the conformationally flexible loop regions. PMID:20361791

  18. LC-MS-Based Metabolomics Study of Marine Bacterial Secondary Metabolite and Antibiotic Production in Salinispora arenicola

    PubMed Central

    Bose, Utpal; Hewavitharana, Amitha K.; Ng, Yi Kai; Shaw, Paul Nicholas; Fuerst, John A.; Hodson, Mark P.

    2015-01-01

    An LC-MS-based metabolomics approach was used to characterise the variation in secondary metabolite production due to changes in the salt content of the growth media as well as across different growth periods (incubation times). We used metabolomics as a tool to investigate the production of rifamycins (antibiotics) and other secondary metabolites in the obligate marine actinobacterial species Salinispora arenicola, isolated from Great Barrier Reef (GBR) sponges, at two defined salt concentrations and over three different incubation periods. The results indicated that a 14 day incubation period is optimal for the maximum production of rifamycin B, whereas rifamycin S and W achieve their maximum concentration at 29 days. A “chemical profile” link between the days of incubation and the salt concentration of the growth medium was shown to exist and reliably represents a critical point for selection of growth medium and harvest time. PMID:25574739

  19. Degradation of fluoroquinolone antibiotics and identification of metabolites/transformation products by liquid chromatography-tandem mass spectrometry.

    PubMed

    Maia, Alexandra S; Ribeiro, Ana R; Amorim, Catarina L; Barreiro, Juliana C; Cass, Quezia B; Castro, Paula M L; Tiritan, Maria Elizabeth

    2014-03-14

    Antibiotics are a therapeutic class widely found in environmental matrices and extensively studied due to its persistence and implications for multi-resistant bacteria development. This work presents an integrated approach of analytical multi-techniques on assessing biodegradation of fluorinated antibiotics at a laboratory-scale microcosmos to follow removal and formation of intermediate compounds. Degradation of four fluoroquinolone antibiotics, namely Ofloxacin (OFL), Norfloxacin (NOR), Ciprofloxacin (CPF) and Moxifloxacin (MOX), at 10 mg L(-1) using a mixed bacterial culture, was assessed for 60 days. The assays were followed by a developed and validated analytical method of LC with fluorescence detection (LC-FD) using a Luna Pentafluorophenyl (2) 3 μm column. The validated method demonstrated good selectivity, linearity (r(2)>0.999), intra-day and inter-day precisions (RSD<2.74%) and accuracy. The quantification limits were 5 μg L(-1) for OFL, NOR and CPF and 20 μg L(-1) for MOX. The optimized conditions allowed picturing metabolites/transformation products formation and accumulation during the process, stating an incomplete mineralization, also shown by fluoride release. OFL and MOX presented the highest (98.3%) and the lowest (80.5%) extent of degradation after 19 days of assay, respectively. A representative number of samples was selected and analyzed by LC-MS/MS with triple quadrupole and the molecular formulas were confirmed by a quadruple time of flight analyzer (QqTOF). Most of the intermediates were already described as biodegradation and/or photodegradation products in different conditions; however unknown metabolites were also identified. The microbial consortium, even when exposed to high levels of FQ, presented high percentages of degradation, never reported before for these compounds. PMID:24548434

  20. GlycoMaster — Software for Glycopeptide Identification with Combined ETD and CID/HCD Spectra

    PubMed Central

    Xin, L.; Shan, P.

    2011-01-01

    Objective: To automate the data analysis for the identification of glycopeptides with combined ETD and CID/HCD fragmentation. The inputs for GlycoMaster software include the raw mass spectrometry data of a Thermo Orbitrap instrument and the list of proteins in the sample. The list of proteins can be identified from the same mass spectrometry data by using a database search method. The software uses the signature ions of simple sugars in the HCD spectra to identify the HCD-ETD spectrum pairs of glycopeptides. Then the ETD spectrum in each pair is used to identify the glycopeptides sequence, the glycosylation site and glycan mass. The output of the software is an excel file that contains information about the identified glycopeptides, including glycan composition, mass error, glycan components, glycosylation site and glycopeptide sequence. A score is associated with each identification result that can be used to sort the identifications according to confidence. GlycoMaster was tested with an ETD-CID dataset containing 3561 MS and 2738 MS/MS spectra from tryptic digest of reduced and alkylated 12 standard protein mixture containing 3 glycoproteins (human serotransferrin, chicken ovalabumin and ovomucoid) from Sigma. Glycopeptides were enriched on cellulose column or by using ZIC-HILIC spin columns from EMD. Purified glycopeptides were analyzed by LTQ Orbitrap Velos ETD. PEAKSTM Studio Suite was used for spectral preprocessing and protein identification. GlycoMaster reported 161 identified HCD-ETD spectrum pairs of glycopeptides. 95 of 161 were manually validated. 68 glycopeptides were reported by GlycoMaster, and 40 glycopeptides were validated.

  1. Atpenins, new antifungal antibiotics produced by Penicillium sp. Production, isolation, physico-chemical and biological properties.

    PubMed

    Omura, S; Tomoda, H; Kimura, K; Zhen, D Z; Kumagai, H; Igarashi, K; Imamura, N; Takahashi, Y; Tanaka, Y; Iwai, Y

    1988-12-01

    Penicillium sp. FO-125, a soil isolate, was found to produce a new antifungal antibiotic complex named atpenin. Three components A4, A5 and B were isolated from the fermentation broth of the producing strain by solvent extraction, silica gel column chromatography and HPLC. The molecular formula of atpenins A4, A5 and B were determined to be C15H22NO5Cl, C15H21NO5Cl2 and C15H23NO5, respectively, on the basis of high resolution electron impact mass spectrometry and elemental analysis. They are active against filamentous fungi, especially, Trichophyton sp. PMID:3209470

  2. X-domain of peptide synthetases recruits oxygenases crucial for glycopeptide biosynthesis.

    PubMed

    Haslinger, Kristina; Peschke, Madeleine; Brieke, Clara; Maximowitsch, Egle; Cryle, Max J

    2015-05-01

    Non-ribosomal peptide synthetase (NRPS) mega-enzyme complexes are modular assembly lines that are involved in the biosynthesis of numerous peptide metabolites independently of the ribosome. The multiple interactions between catalytic domains within the NRPS machinery are further complemented by additional interactions with external enzymes, particularly focused on the final peptide maturation process. An important class of NRPS metabolites that require extensive external modification of the NRPS-bound peptide are the glycopeptide antibiotics (GPAs), which include vancomycin and teicoplanin. These clinically relevant peptide antibiotics undergo cytochrome P450-catalysed oxidative crosslinking of aromatic side chains to achieve their final, active conformation. However, the mechanism underlying the recruitment of the cytochrome P450 oxygenases to the NRPS-bound peptide was previously unknown. Here we show, through in vitro studies, that the X-domain, a conserved domain of unknown function present in the final module of all GPA NRPS machineries, is responsible for the recruitment of oxygenases to the NRPS-bound peptide to perform the essential side-chain crosslinking. X-ray crystallography shows that the X-domain is structurally related to condensation domains, but that its amino acid substitutions render it catalytically inactive. We found that the X-domain recruits cytochrome P450 oxygenases to the NRPS and determined the interface by solving the structure of a P450-X-domain complex. Additionally, we demonstrated that the modification of peptide precursors by oxygenases in vitro--in particular the installation of the second crosslink in GPA biosynthesis--occurs only in the presence of the X-domain. Our results indicate that the presentation of peptidyl carrier protein (PCP)-bound substrates for oxidation in GPA biosynthesis requires the presence of the NRPS X-domain to ensure conversion of the precursor peptide into a mature aglycone, and that the carrier protein

  3. Crystallization and preliminary X-ray analysis of AbsC, a novel regulator of antibiotic production in Streptomyces coelicolor

    SciTech Connect

    Stevenson, Clare E. M.; Kock, Holger; Mootien, Saraspadee; Davies, Sîan C.; Bibb, Mervyn J.; Lawson, David M.

    2007-03-01

    A novel regulator of antibiotic production in S. coelicolor, AbsC, has been crystallized in space group P2{sub 1}2{sub 1}2{sub 1}. X-ray data to 2.25 Å resolution were collected on station PX 14.1 at Daresbury. Crystals of recombinant AbsC (subunit MW = 18 313 Da; 158 amino acids), a novel regulator of antibiotic production from Streptomyces coelicolor, were grown by vapour diffusion. The protein crystallizes in space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 43.53, b = 121.30, c = 143.75 Å. Native data to a resolution of 2.25 Å were recorded at station PX 14.1 (Daresbury) from a single crystal. Preliminary analysis of these data suggests that the asymmetric unit contains four copies of the AbsC monomer, giving an estimated solvent content of 47.0%. AbsC belongs to the MarR family of proteins that mediate ligand-responsive transcriptional control.

  4. The bldB Gene Encodes a Small Protein Required for Morphogenesis, Antibiotic Production, and Catabolite Control in Streptomyces coelicolor

    PubMed Central

    Pope, Margaret K.; Green, Brian; Westpheling, Janet

    1998-01-01

    Mutants blocked at the earliest stage of morphological development in Streptomyces species are called bld mutants. These mutants are pleiotropically defective in the initiation of development, the ability to produce antibiotics, the ability to regulate carbon utilization, and the ability to send and/or respond to extracellular signals. Here we report the identification and partial characterization of a 99-amino-acid open reading frame (ORF99) that is capable of restoring morphogenesis, antibiotic production, and catabolite control to all of the bldB mutants. Of the existing bld mutants, bldB is of special interest because the phenotype of this mutant is the most pleiotropic. DNA sequence analysis of ORF99 from each of the existing bldB mutants identified base changes either within the coding region of the predicted protein or in the regulatory region of the gene. Primer extension analysis identified an apparent transcription start site. A promoter fusion to the xylE reporter gene showed that expression of bldB is apparently temporally regulated and that the bldB gene product is involved in the regulation of its own expression. PMID:9515926

  5. Antigiardial activity of glycoproteins and glycopeptides from Ziziphus honey.

    PubMed

    Mohammed, Seif Eldin A; Kabashi, Ahmed S; Koko, Waleed S; Azim, M Kamran

    2015-01-01

    Natural honey contains an array of glycoproteins, proteoglycans and glycopeptides. Size-exclusion chromatography fractionated Ziziphus honey proteins into five peaks with molecular masses in the range from 10 to >200 kDa. The fractionated proteins exhibited in vitro activities against Giardia lamblia with IC50 values ≤ 25 μg/mL. Results indicated that honey proteins were more active as antiprotozoal agents than metronidazole. This study indicated the potential of honey proteins and peptides as novel antigiardial agents. PMID:25587739

  6. Opioid glycopeptide analgesics derived from endogenous enkephalins and endorphins

    PubMed Central

    Li, Yingxue; Lefever, Mark R; Muthu, Dhanasekaran; Bidlack, Jean M; Bilsky, Edward J; Polt, Robin

    2012-01-01

    Over the past two decades, potent and selective analgesics have been developed from endogenous opioid peptides. Glycosylation provides an important means of modulating interaction with biological membranes, which greatly affects the pharmacodynamics and pharmacokinetics of the resulting glycopeptide analogues. Furthermore, manipulation of the membrane affinity allows penetration of cellular barriers that block efficient drug distribution, including the blood–brain barrier. Extremely potent and selective opiate agonists have been developed from endogenous peptides, some of which show great promise as drug candidates. PMID:22300099

  7. Antifreeze glycopeptide adsorption on single crystal ice surfaces using ellipsometry

    PubMed Central

    Wilson, P. W.; Beaglehole, D.; DeVries, A. L.

    1993-01-01

    Antarctic fishes synthesise antifreeze proteins which can effectively inhibit the growth of ice crystals. The mechanism relies on adsorption of these proteins to the ice surface. Ellipsometry has been used to quantify glycopeptide antifreeze adsorption to the basal and prism faces of single ice crystals. The rate of accumulation was determined as a function of time and at concentrations between 0.0005 and 1.2 mg/ml. Estimates of packing density at saturation coverage have been made for the basal and prism faces. PMID:19431902

  8. Vancomycin Molecular Interactions: Antibiotic and Enantioselective Mechanisms

    NASA Astrophysics Data System (ADS)

    Ward, Timothy J.; Gilmore, Aprile; Ward, Karen; Vowell, Courtney

    Medical studies established that vancomycin and other related macrocyclic antibiotics have an enhanced antimicrobial activity when they are associated as dimers. The carbohydrate units attached to the vancomycin basket have an essential role in the dimerization reaction. Covalently synthesized dimers were found active against vancomycin-resistant bacterial strains. A great similarity between antibiotic potential and enantioselectivity was established. A covalent vancomycin dimer was studied in capillary electrophoresis producing excellent chiral separation of dansyl amino acids. Balhimycin is a macrocyclic glycopeptide structurally similar to vancomycin. The small differences are, however, responsible for drastic differences in enantioselectivity in the same experimental conditions. Contributions from studies examining vancomycin's mechanism for antimicrobial activity have substantially aided our understanding of its mechanism in chiral recognition.

  9. Lipid II as a target for antibiotics.

    PubMed

    Breukink, Eefjan; de Kruijff, Ben

    2006-04-01

    Lipid II is a membrane-anchored cell-wall precursor that is essential for bacterial cell-wall biosynthesis. The effectiveness of targeting Lipid II as an antibacterial strategy is highlighted by the fact that it is the target for at least four different classes of antibiotic, including the clinically important glycopeptide antibiotic vancomycin. However, the growing problem of bacterial resistance to many current drugs, including vancomycin, has led to increasing interest in the therapeutic potential of other classes of compound that target Lipid II. Here, we review progress in understanding of the antibacterial activities of these compounds, which include lantibiotics, mannopeptimycins and ramoplanin, and consider factors that will be important in exploiting their potential as new treatments for bacterial infections. PMID:16531990

  10. Antibiotic Agents

    MedlinePlus

    ... Work Contact Us ABOUT THE ISSUE What is Antibiotic Resistance? General Background Science of Resistance Glossary References POLICY ... for Adaptation Genetics and Drug Resistance Reservoirs of Antibiotic Resistance Project (ROAR) INTERNATIONAL CHAPTERS APUA Chapter Network Africa ...

  11. Antibiotic Safety

    MedlinePlus

    ... specific to women Antibiotics can lead to vaginal yeast infections. This happens because antibiotics kill the normal bacteria in the vagina and this causes yeast to grow rapidly. Symptoms of a yeast infection ...

  12. Evaluation and validation of a multi-residue method based on biochip technology for the simultaneous screening of six families of antibiotics in muscle and aquaculture products.

    PubMed

    Gaudin, Valérie; Hedou, Celine; Soumet, Christophe; Verdon, Eric

    2016-01-01

    The Evidence Investigator™ system (Randox, UK) is a biochip and semi-automated system. The microarray kit II (AM II) is capable of detecting several compounds belonging to different families of antibiotics: quinolones, ceftiofur, thiamphenicol, streptomycin, tylosin and tetracyclines. The performance of this innovative system was evaluated for the detection of antibiotic residues in new matrices, in muscle of different animal species and in aquaculture products. The method was validated according to the European Decision No. EC/2002/657 and the European guideline for the validation of screening methods, which represents a complete initial validation. The false-positive rate was equal to 0% in muscle and in aquaculture products. The detection capabilities CCβ for 12 validated antibiotics (enrofloxacin, difloxacin, ceftiofur, desfuroyl ceftiofur cysteine disulfide, thiamphenicol, florfenicol, tylosin, tilmicosin, streptomycin, dihydrostreptomycin, tetracycline, doxycycline) were all lower than the respective maximum residue limits (MRLs) in muscle from different animal origins (bovine, ovine, porcine, poultry). No cross-reactions were observed with other antibiotics, neither with the six detected families nor with other families of antibiotics. The AM II kit could be applied to aquaculture products but with higher detection capabilities from those in muscle. The detection capabilities CCβ in aquaculture products were respectively at 0.25, 0.10 and 0.5 of the respective MRL in aquaculture products for enrofloxacin, tylosin and oxytetracycline. The performance of the AM II kit has been compared with other screening methods and with the performance characteristics previously determined in honey. PMID:26612266

  13. Insights into solar TiO2-assisted photocatalytic oxidation of two antibiotics employed in aquatic animal production, oxolinic acid and oxytetracycline.

    PubMed

    Pereira, João H O S; Reis, Ana C; Queirós, Daniel; Nunes, Olga C; Borges, Maria T; Vilar, Vítor J P; Boaventura, Rui A R

    2013-10-01

    In this study, solar driven TiO2-assisted heterogeneous photocatalytic experiments in a pilot-plant with compound parabolic collectors (CPCs) were carried out to study the degradation of two authorized veterinary antibiotics with particular relevance in finfish aquaculture, oxolinic acid (OXA) and oxytetracycline (OTC), using pure solutions of individual or mixed antibiotics. Firstly, the influence of natural solar photolysis was assessed for each antibiotic. Secondly, photocatalytic degradation kinetic rate constants for individual and mixed antibiotics were compared, using a catalyst load of 0.5 g L(-1) and an initial pH around 7.5. Thirdly, for individually photocatalytic-treated OXA and OTC in the same conditions, the growth inhibition of Escherichia coli DSM 1103 was followed, and the mineralization extent was assessed by the residual dissolved organic carbon (DOC), low-molecular-weight carboxylate anions and inorganic ions concentration. Finally, the effect of inorganic ions, such as chlorides, sulfates, nitrates, phosphates, ammonium and bicarbonates, on the photocatalytic degradation of individual solutions of OXA and OTC was also evaluated and the formation of different reactive oxygen species were probed using selective scavengers. The removal profiles of each antibiotic, both as single component or in mixture were similar, being necessary 2.5 kJ L(-1) of solar UV energy to fully remove them, and 18 kJ(UV) L(-1) to achieve 73% and 81% mineralization, for OXA and OTC, respectively. The remaining organic carbon content was mainly due to low-molecular-weight carboxylate anions. After complete removal of the antibiotics, the remaining degradation by-products no longer showed antibacterial activity. Also, 10% and 55% of the nitrogen content of each antibiotic was converted to ammonium, while no conversion to nitrite or nitrate was detected. The presence of phosphates hindered considerably the removal of both antibiotics, whereas the presence of other inorganic

  14. Liofilchem® Chromatic VRE and vancomycin MIC Test Strip detected glycopeptide resistance in a vanB neonatal Enterococcus faecium isolate showing alternate vancomycin susceptibility and resistance with bioMérieux Vitek2

    PubMed Central

    Savini, Vincenzo; Marrollo, Roberta; Coclite, Eleonora; Fusilli, Paola; D’Incecco, Carmine; Fazii, Paolo; Gherardi, Giovanni

    2014-01-01

    A 1-month old neonate urine sample yielded vanB Enterococcus faecium; nevertheless, the isolate alternatively showed susceptibility and resistance to vancomycin with bioMérieux Vitek2 (cards AST592, AST632, AST586), while glycopeptide resistance was detected by Liofilchem® vancomycin MIC Test Strip and disc along with the Chromatic VRE chromogenic medium. This communication emphasizes that, as vanB gene may be heterogeneously expressed within a given Enterococcus population, glycopeptide resistance may be missed when using automated systems for antibiotic susceptibility testing. We suggest therefore that vancomycin in vitro activity be studied on all clinical isolates through agar methods, including use of chromogenic media. PMID:25337280

  15. Liofilchem(®) Chromatic VRE and vancomycin MIC Test Strip detected glycopeptide resistance in a vanB neonatal Enterococcus faecium isolate showing alternate vancomycin susceptibility and resistance with bioMérieux Vitek2.

    PubMed

    Savini, Vincenzo; Marrollo, Roberta; Coclite, Eleonora; Fusilli, Paola; D'Incecco, Carmine; Fazii, Paolo; Gherardi, Giovanni

    2014-01-01

    A 1-month old neonate urine sample yielded vanB Enterococcus faecium; nevertheless, the isolate alternatively showed susceptibility and resistance to vancomycin with bioMérieux Vitek2 (cards AST592, AST632, AST586), while glycopeptide resistance was detected by Liofilchem(®) vancomycin MIC Test Strip and disc along with the Chromatic VRE chromogenic medium. This communication emphasizes that, as vanB gene may be heterogeneously expressed within a given Enterococcus population, glycopeptide resistance may be missed when using automated systems for antibiotic susceptibility testing. We suggest therefore that vancomycin in vitro activity be studied on all clinical isolates through agar methods, including use of chromogenic media. PMID:25337280

  16. Antibiotic growth promoters enhance animal production by targeting intestinal bile salt hydrolase and its producers.

    PubMed

    Lin, Jun

    2014-01-01

    The growth-promoting effect of antibiotic growth promoters (AGPs) was correlated with the decreased activity of bile salt hydrolase (BSH), an intestinal bacteria-produced enzyme that exerts negative impact on host fat digestion and utilization. Consistent with this finding, independent chicken studies have demonstrated that AGP usage significantly reduced population of Lactobacillus species, the major BSH-producers in the intestine. Recent finding also demonstrated that some AGPs, such as tetracycline and roxarsone, display direct inhibitory effect on BSH activity. Therefore, BSH is a promising microbiome target for developing novel alternatives to AGPs. Specifically, dietary supplementation of BSH inhibitor may promote host lipid metabolism and energy harvest, consequently enhancing feed efficiency and body weight gain in food animals. PMID:24575079

  17. Antibiotic growth promoters enhance animal production by targeting intestinal bile salt hydrolase and its producers

    PubMed Central

    Lin, Jun

    2014-01-01

    The growth-promoting effect of antibiotic growth promoters (AGPs) was correlated with the decreased activity of bile salt hydrolase (BSH), an intestinal bacteria-produced enzyme that exerts negative impact on host fat digestion and utilization. Consistent with this finding, independent chicken studies have demonstrated that AGP usage significantly reduced population of Lactobacillus species, the major BSH-producers in the intestine. Recent finding also demonstrated that some AGPs, such as tetracycline and roxarsone, display direct inhibitory effect on BSH activity. Therefore, BSH is a promising microbiome target for developing novel alternatives to AGPs. Specifically, dietary supplementation of BSH inhibitor may promote host lipid metabolism and energy harvest, consequently enhancing feed efficiency and body weight gain in food animals. PMID:24575079

  18. A35512, a complex of new antibacterial antibiotics produced by Streptomyces candidus. I. Isolation and characterization.

    PubMed

    Michel, K H; Shah, R M; Hamill, R L

    1980-12-01

    The new antibiotic complex A35512 produced by Streptomyces candidus was isolated from the filtered fermentation broth. The individual factors A, B, C, E, and H were separated and purified by column chromatography. A35512B, the major factor, was isolated as the dihydrochloride salt, a white crystalline compound with an approximate empirical formula of C90H101 N8O39Cl.2HCl. The A35512 antibiotics belong to the glycopeptide class of antibiotics and possess high in vitro and in vivo activity against Gram-positive bacteria. PMID:7251482

  19. Production of destomycin-A antibiotic by Streptomyces sp. using rice straw as fermented substrate.

    PubMed

    Atta, H M; Abul-Hamd, A T; Radwan, H G

    2009-01-01

    Hundred and twenty microbial isolates could be isolated from different soil samples collected from different localities in Egypt. One of the actinomycete culture AZ-H-A5 from three cultures was found to produce a wide spectrum antimicrobial agent when cultivated on rice straw. The actinomycete AZ-H-A5 could be isolated from a soil sample collected from Helwan district, Egypt. The nucleotide sequence of the 16s RNA gene (1.5 Kb) of the most potent strain evidenced an 85% similarity with Streptomyces pseudovenezue, EU841712 and Streptomyces galilaeus. From the taxonomic features, the actinomycetes isolate AZ-H-A5 matches with Streptomyces rimosus in the morphological, physiological and biochemical characters. Thus, it was given the suggested name Streptomyces rimosus, AZ-H-A5. The parameters controlling the biosynthetic process of antimicrobial agent formation including: inoculum size, different pH values, different temperatures, different incubation period, and different carbon and nitrogen sources, potassium nitrate, K2HPO4, MgSO4.7H2O and KCl concentrations were fully investigates. The active metabolite was extracted using ethyl acetate (1:1, v/v) at pH 7.0. The separation of the active ingredient and its purification was performed using both thin layer chromatography (TLC) and column chromatography (CC) techniques. The physicochemical characteristics of the purified antibiotic viz. color, melting point, solubility, elemental analysis, spectroscopic characteristics and chemical reactions have been investigated. This analysis indicates a suggested empirical formula of C20H37N13O13. The minimum inhibition concentrations "MICs" of the purified antimicrobial agent were also determined. The purified antimicrobial agent was suggestive of being belonging to Destomycin-A antibiotic produced by Streptomyces rimosus, AZ-H-A5. PMID:20222575

  20. Glycopeptide Resistance in Gram-Positive Cocci: A Review

    PubMed Central

    Sujatha, S.; Praharaj, Ira

    2012-01-01

    Vancomycin-resistant enterococci (VRE) have emerged as important nosocomial pathogens in the past two decades all over the world and have seriously limited the choices available to clinicians for treating infections caused by these agents. Methicillin-resistant Staphylococcus aureus, perhaps the most notorious among the nosocomial pathogens, was till recently susceptible to vancomycin and the other glycopeptides. Emergence of vancomycin nonsusceptible strains of S. aureus has led to a worrisome scenario where the options available for treating serious infections due to these organisms are very limited and not well evaluated. Vancomycin resistance in clinically significant isolates of coagulase-negative staphylococci is also on the rise in many setups. This paper aims to highlight the genetic basis of vancomycin resistance in Enterococcus species and S. aureus. It also focuses on important considerations in detection of vancomycin resistance in these gram-positive bacteria. The problem of glycopeptide resistance in clinical isolates of coagulase-negative staphylococci and the phenomenon of vancomycin tolerance seen in some strains of Streptococcus pneumoniae has also been discussed. Finally, therapeutic options available and being developed against these pathogens have also found a mention. PMID:22778729

  1. Highly Selective Enrichment of Glycopeptides Based on Zwitterionically Functionalized Soluble Nanopolymers.

    PubMed

    Cao, Weiqian; Huang, Jiangming; Jiang, Biyun; Gao, Xing; Yang, Pengyuan

    2016-01-01

    Efficient glycopeptides enrichment prior to mass spectrometry analysis is essential for glycoproteome study. ZIC-HILIC (zwitterionic hydrophilic interaction liquid chromatography) based glycopeptides enrichment approaches have been attracting more attention for several benefits like easy operating, high enrichment specificity and intact glycopeptide retained. In this study, Poly (amidoamine) dendrimer (PAMAM) was adopted for the synthesis of zwitterionically functionalized (ZICF) materials for glycopeptide enrichment. The multiple branched structure and good solubility of ZICF-PAMAM enables a sufficient interaction with glycopeptides. The ZICF-PAMAM combined with the FASP-mode enrichment strategy exhibits more superior performance compared with the existing methods. It has the minimum detectable concentration of femtomolar level and high recovery rate of over 90.01%, and can efficiently enrich glycopeptides from complex biological samples even for merely 0.1 μL human serum. The remarkable glycopeptides enrichment capacity of ZICF-PAMAM highlights the potential application in in-depth glycoproteome research, which may open up new opportunities for the development of glycoproteomics. PMID:27412817

  2. Highly Selective Enrichment of Glycopeptides Based on Zwitterionically Functionalized Soluble Nanopolymers

    NASA Astrophysics Data System (ADS)

    Cao, Weiqian; Huang, Jiangming; Jiang, Biyun; Gao, Xing; Yang, Pengyuan

    2016-07-01

    Efficient glycopeptides enrichment prior to mass spectrometry analysis is essential for glycoproteome study. ZIC-HILIC (zwitterionic hydrophilic interaction liquid chromatography) based glycopeptides enrichment approaches have been attracting more attention for several benefits like easy operating, high enrichment specificity and intact glycopeptide retained. In this study, Poly (amidoamine) dendrimer (PAMAM) was adopted for the synthesis of zwitterionically functionalized (ZICF) materials for glycopeptide enrichment. The multiple branched structure and good solubility of ZICF-PAMAM enables a sufficient interaction with glycopeptides. The ZICF-PAMAM combined with the FASP-mode enrichment strategy exhibits more superior performance compared with the existing methods. It has the minimum detectable concentration of femtomolar level and high recovery rate of over 90.01%, and can efficiently enrich glycopeptides from complex biological samples even for merely 0.1 μL human serum. The remarkable glycopeptides enrichment capacity of ZICF-PAMAM highlights the potential application in in-depth glycoproteome research, which may open up new opportunities for the development of glycoproteomics.

  3. Presence of fucosyl residues on the oligosaccharide antennae of membrane glycopeptides of human neuroblastoma cells

    SciTech Connect

    Santer, U.V.; Glick, M.C.

    1983-09-01

    Fucosyl residues linked alpha 1 leads to 3 or 4 to N-acetylglucosamine were found in large amounts on glycopeptides from the membranes of human tumor cells of neurectodermal origin but not on membrane glycopeptides from human fibroblasts. The fucosyl residues were detected by release of radioactive fucose from the glycopeptides with an almond alpha-L-fucosidase specific for fucosyl alpha 1 leads to 3(4)-N-acetylglucosamine. In other studies, the linkage was shown to be alpha 1 leads to 3 by nuclear magnetic resonance analysis. Glycopeptides containing these fucosyl residues from four human neuroblastoma cell lines were defined by binding to immobilized lectins. In addition, the glycopeptides from one human neuroblastoma cell line, CHP-134, were further characterized by enzyme degradation and columns calibrated for size and charge. The antennary position of fucosyl alpha 1 leads to 3-N-acetylglucosamine on the glycopeptides was demonstrated by the use of exoglycosidases and endoglycosidase D, since complete degradation to yield fucosyl-N-acetylglucosaminylasparagine was obtained only after treatment with almond alpha-L-fucosidase prior to the sequential degradation. Fucosyl alpha 1 leads to 3-N-acetylglucosamine was present on most size and charge classes of membrane glycopeptides and therefore was not limited to a few glycoproteins. Since the almond alpha-L-fucosidase cleaves fucosyl residues from glycoproteins, the physiological effects of the increased specific fucosylation on human tumors of neurectodermal origin can be examined.

  4. Highly Selective Enrichment of Glycopeptides Based on Zwitterionically Functionalized Soluble Nanopolymers

    PubMed Central

    Cao, Weiqian; Huang, Jiangming; Jiang, Biyun; Gao, Xing; Yang, Pengyuan

    2016-01-01

    Efficient glycopeptides enrichment prior to mass spectrometry analysis is essential for glycoproteome study. ZIC-HILIC (zwitterionic hydrophilic interaction liquid chromatography) based glycopeptides enrichment approaches have been attracting more attention for several benefits like easy operating, high enrichment specificity and intact glycopeptide retained. In this study, Poly (amidoamine) dendrimer (PAMAM) was adopted for the synthesis of zwitterionically functionalized (ZICF) materials for glycopeptide enrichment. The multiple branched structure and good solubility of ZICF-PAMAM enables a sufficient interaction with glycopeptides. The ZICF-PAMAM combined with the FASP-mode enrichment strategy exhibits more superior performance compared with the existing methods. It has the minimum detectable concentration of femtomolar level and high recovery rate of over 90.01%, and can efficiently enrich glycopeptides from complex biological samples even for merely 0.1 μL human serum. The remarkable glycopeptides enrichment capacity of ZICF-PAMAM highlights the potential application in in-depth glycoproteome research, which may open up new opportunities for the development of glycoproteomics. PMID:27412817

  5. In Vitro Activities of Arylomycin Natural-Product Antibiotics against Staphylococcus epidermidis and Other Coagulase-Negative Staphylococci ▿ †

    PubMed Central

    Smith, Peter A.; Powers, Michael E.; Roberts, Tucker C.; Romesberg, Floyd E.

    2011-01-01

    The arylomycins are a class of natural-product antibiotics that act via the inhibition of type I signal peptidase (SPase), and we have found in diverse bacteria that their activity is limited by the presence of a resistance-conferring Pro residue in SPase that reduces inhibitor binding. We have also demonstrated that Staphylococcus epidermidis, which lacks this Pro residue, is extremely susceptible to the arylomycins. Here, to further explore the potential utility of the arylomycins, we report an analysis of the activity of a synthetic arylomycin derivative, arylomycin C16, against clinical isolates of S. epidermidis and other coagulase-negative staphylococci (CoNS) from distinct geographical locations. Against many important species of CoNS, including S. epidermidis, S. haemolyticus, S. lugdunensis, and S. hominis, we find that arylomycin C16 exhibits activity equal to or greater than that of vancomycin, the antibiotic most commonly used to treat CoNS infections. While the susceptibility was generally correlated with the absence of the previously identified Pro residue, several cases were identified where additional factors also appear to contribute. PMID:21189343

  6. Development, Antibiotic Production, and Ribosome Assembly in Streptomyces venezuelae Are Impacted by RNase J and RNase III Deletion

    PubMed Central

    Jones, Stephanie E.; Leong, Vivian; Ortega, Joaquin

    2014-01-01

    RNA metabolism is a critical but frequently overlooked control element affecting virtually every cellular process in bacteria. RNA processing and degradation is mediated by a suite of ribonucleases having distinct cleavage and substrate specificity. Here, we probe the role of two ribonucleases (RNase III and RNase J) in the emerging model system Streptomyces venezuelae. We show that each enzyme makes a unique contribution to the growth and development of S. venezuelae and further affects the secondary metabolism and antibiotic production of this bacterium. We demonstrate a connection between the action of these ribonucleases and translation, with both enzymes being required for the formation of functional ribosomes. RNase III mutants in particular fail to properly process 23S rRNA, form fewer 70S ribosomes, and show reduced translational processivity. The loss of either RNase III or RNase J additionally led to the appearance of a new ribosomal species (the 100S ribosome dimer) during exponential growth and dramatically sensitized these mutants to a range of antibiotics. PMID:25266378

  7. Reciprocal immune benefit based on complementary production of antibiotics by the leech Hirudo verbana and its gut symbiont Aeromonas veronii

    PubMed Central

    Tasiemski, Aurélie; Massol, François; Cuvillier-Hot, Virginie; Boidin-Wichlacz, Céline; Roger, Emmanuel; Rodet, Franck; Fournier, Isabelle; Thomas, Frédéric; Salzet, Michel

    2015-01-01

    The medicinal leech has established a long-term mutualistic association with Aeromonas veronii, a versatile bacterium which can also display free-living waterborne and fish- or human-pathogenic lifestyles. Here, we investigated the role of antibiotics in the dynamics of interaction between the leech and its gut symbiont Aeromonas. By combining biochemical and molecular approaches, we isolated and identified for the first time the antimicrobial peptides (AMPs) produced by the leech digestive tract and by its symbiont Aeromonas. Immunohistochemistry data and PCR analyses evidenced that leech AMP genes are induced in the gut epithelial cells when Aeromonas load is low (starved animals), while repressed when Aeromonas abundance is the highest (post blood feeding). The asynchronous production of AMPs by both partners suggests that these antibiotic substances (i) provide them with reciprocal protection against invasive bacteria and (ii) contribute to the unusual simplicity of the gut microflora of the leech. This immune benefit substantially reinforces the evidence of an evolutionarily stable association between H. verbana and A. veronii. Altogether these data may provide insights into the processes making the association with an Aeromonas species in the digestive tract either deleterious or beneficial. PMID:26635240

  8. Novel antibiotics for the treatment of Staphylococcus aureus.

    PubMed

    Ohlsen, Knut

    2009-11-01

    Staphylococcus aureus is a leading cause of nosocomial and community-acquired infection associated with significant morbidity and mortality. Antibiotic treatment of infections owing to S. aureus have become increasingly challenging as the pathogen has acquired a broad spectrum of antibiotic resistance mechanisms. In particular, emergence and spread of methicillin-resistant S. aureus (MRSA) progressed to a global health threat. The glycopeptides antibiotics vancomycin and teicoplanin have remained as the drugs of last resort for more than 20 years. Fortunately, in addition to the glycopeptides, several novel antibiotics including linezolid, daptomycin, tigecycline, quinupristin/dalfopristin and ceftobiprole acting against MRSA have been recently introduced into clinical practice broadening therapeutic options. Although the arsenal of antistaphylococcal drugs has filled up in recent years, the rate of MRSA infection continues to be high in most countries. This demands an ongoing search for new antibacterials and lead compounds as well as development of alternative therapies and faster diagnostics to ensure effective anti-staphylococcal therapy in the future. PMID:22112259

  9. Use of Tn5lac to study expression of genes required for production of the antibiotic TA.

    PubMed Central

    Tolchinsky, S; Fuchs, N; Varon, M; Rosenberg, E

    1992-01-01

    The beta-galactosidase activities arising from Tn5lac insertions in several genes required for antibiotic TA production were measured under different growth conditions. In all of the non-TA-producing mutants, the beta-galactosidase specific activity was higher when the cells were grown in nutrient-limited 0.5CTS medium (0.5% Casitone plus alanine, serine, and glucose) than in rich 2CT medium (2% Casitone). One of the mutants, 420, had low beta-galactosidase specific activity in both media. The other seven mutants containing inserts in genes essential for TA production had specific activities of 139 to 367 U/mg of protein in 0.5CTS medium and 11 to 48 U/mg of protein in 2CT medium. The beta-galactosidase specific activities of two strains, 1030 and 420, increased during exponential growth in 0.5CTS medium. The beta-galactosidase specific activities of both strains increased greatly when the cells were grown in the presence of magnesium phosphate, which traps ammonium ions. The Tn5lac insertions in 1030 and 420 were used to screen for mutants with increased levels of transcription. An N-methyl-N'-nitro-N-nitrosoguanidine-induced mutation in 1030 that mapped 17 kb from the omega 1010 insert increased the specific activity of beta-galactosidase 21 times in 2CT medium. The regulatory mutation appears to release the repression caused by 2CT medium. A UV-induced mutation in 420 increased the beta-galactosidase specific activity 1.4 to 2.4 times. Medium conditions that affect the transcription of TA genes are discussed in terms of enhanced antibiotic TA production. PMID:1444312

  10. Use of Tn5lac to study expression of genes required for production of the antibiotic TA.

    PubMed

    Tolchinsky, S; Fuchs, N; Varon, M; Rosenberg, E

    1992-10-01

    The beta-galactosidase activities arising from Tn5lac insertions in several genes required for antibiotic TA production were measured under different growth conditions. In all of the non-TA-producing mutants, the beta-galactosidase specific activity was higher when the cells were grown in nutrient-limited 0.5CTS medium (0.5% Casitone plus alanine, serine, and glucose) than in rich 2CT medium (2% Casitone). One of the mutants, 420, had low beta-galactosidase specific activity in both media. The other seven mutants containing inserts in genes essential for TA production had specific activities of 139 to 367 U/mg of protein in 0.5CTS medium and 11 to 48 U/mg of protein in 2CT medium. The beta-galactosidase specific activities of two strains, 1030 and 420, increased during exponential growth in 0.5CTS medium. The beta-galactosidase specific activities of both strains increased greatly when the cells were grown in the presence of magnesium phosphate, which traps ammonium ions. The Tn5lac insertions in 1030 and 420 were used to screen for mutants with increased levels of transcription. An N-methyl-N'-nitro-N-nitrosoguanidine-induced mutation in 1030 that mapped 17 kb from the omega 1010 insert increased the specific activity of beta-galactosidase 21 times in 2CT medium. The regulatory mutation appears to release the repression caused by 2CT medium. A UV-induced mutation in 420 increased the beta-galactosidase specific activity 1.4 to 2.4 times. Medium conditions that affect the transcription of TA genes are discussed in terms of enhanced antibiotic TA production. PMID:1444312

  11. The multifaceted roles of antibiotics and antibiotic resistance in nature

    PubMed Central

    Sengupta, Saswati; Chattopadhyay, Madhab K.; Grossart, Hans-Peter

    2013-01-01

    Antibiotics are chemotherapeutic agents, which have been a very powerful tool in the clinical management of bacterial diseases since the 1940s. However, benefits offered by these magic bullets have been substantially lost in subsequent days following the widespread emergence and dissemination of antibiotic-resistant strains. While it is obvious that excessive and imprudent use of antibiotics significantly contributes to the emergence of resistant strains, antibiotic resistance is also observed in natural bacteria of remote places unlikely to be impacted by human intervention. Both antibiotic biosynthetic genes and resistance-conferring genes have been known to evolve billions of years ago, long before clinical use of antibiotics. Hence it appears that antibiotics and antibiotics resistance determinants have some other roles in nature, which often elude our attention because of overemphasis on the therapeutic importance of antibiotics and the crisis imposed by the antibiotic resistance in pathogens. In the natural milieu, antibiotics are often found to be present in sub-inhibitory concentrations acting as signaling molecules supporting the process of quorum sensing and biofilm formation. They also play an important role in the production of virulence factors and influence host–parasite interactions (e.g., phagocytosis, adherence to the target cell, and so on). The evolutionary and ecological aspects of antibiotics and antibiotic resistance in the naturally occurring microbial community are little understood. Therefore, the actual role of antibiotics in nature warrants in-depth investigations. Studies on such an intriguing behavior of the microorganisms promise insight into the intricacies of the microbial physiology and are likely to provide some lead in controlling the emergence and subsequent dissemination of antibiotic resistance. This article highlights some of the recent findings on the role of antibiotics and the genes that confer resistance to antibiotics

  12. Phenotypic characteristics of coagulase-negative staphylococci: typing and antibiotic susceptibility.

    PubMed

    Jarløv, J O

    1999-01-01

    expensive and sophisticated equipment. Various typing schemes for S. epidermidis, i.e. typing which involves several typing methods, have been tested: lectin typing, DNA-plasmid profile analysis, antibiotic susceptibility testing, phage typing, and slime production lectin typing, antibiotic susceptibility testing, biotyping (Minibact-S), phage typing antibiotic susceptibility testing and biotyping (Minibact-S) For use as a "first line" typing scheme in the local clinical microbiology laboratory, the typing of S. epidermidis by combined antibiotic susceptibility testing and biotyping is easy to handle. Antibiotic susceptibility testing should include antibiotics from several groups of antibiotics having different resistance mechanisms. Antibiotic susceptibility among Danish CoNS-strains from blood cultures was studied. A major diversity in species distribution and antibiotic susceptibility was found between different Danish regions, for example methicillin resistant CoNS accounted for 40% in Copenhagen County and only for 21% in Northern Jutland County. Diversity in species distribution was also marked; an example of this is that 73% of the strains from Copenhagen Municipality were identified as S. epidermidis compared to only 46% in Northern Jutland County. In a study from Rigshospitalet, Copenhagen, great diversity in antibiotic susceptibility was detected between the different wards. In four wards investigated, high consumption of carbapenems, Third-generation cephalosporins, and quinolones was associated with high prevalence of methicillin resistance. Furthermore, for ciprofloxacin, ciprofloxacin-resistant CoNS-strains were practically not detected in the Neonatal Ward where ciprofloxacin is not used. In contrast to the nationwide study, glycopeptide resistance was found at Rigshospitalet: 5% of the CoNS strains were teicoplanin-resistant but all strains were vancomycin-susceptible. In both the above mentioned studies, antibiotic resistance was strongly associated with

  13. Antibiotic Resistance of Listeria monocytogenes Isolated from Meat-Processing Environments, Beef Products, and Clinical Cases in Brazil.

    PubMed

    Camargo, Anderson Carlos; de Castilho, Natalia Parma Augusto; da Silva, Danilo Augusto Lopes; Vallim, Deyse Christina; Hofer, Ernesto; Nero, Luís Augusto

    2015-08-01

    The present study aimed to assess the antimicrobial resistance and the presence of virulence markers in 137 Listeria monocytogenes isolates obtained from meat-processing environments, beef products, and clinical cases. All isolates were subject to molecular serogrouping and their antibiotic resistance profiles were assessed against 12 antimicrobials. In addition, isolates were subjected to detection of virulence marker genes (inlA, inlC, inlJ). The isolates were classified into serogroups 4b, 4d, 4a, or 4c (46%), 1/2c or 3c (27%), 1/2a or 3a (13.9%), and 1/2b or 3b (13.1%). All tested isolates presented sensitivity to the majority of the tested antimicrobials, but most of them presented resistance or intermediate resistance to clindamycin (88.3%) and oxacillin (73.7%). Virulence markers were detected in all isolates, demanding further analysis to better characterize their pathogenic potential. PMID:25756759

  14. [Determination of metabolite residues of nitrofuran antibiotics in aquatic products by liquid chromatography-tandem mass spectrometry].

    PubMed

    Wang, Chuanxian; Huang, Fan; Wang, Min; Sheng, Yonggang; Zhang, Jin; Han, Li; Song, Qing; Li, Xiaohong; Xu, Dunming; Ding, Zhuoping

    2013-03-01

    A method was developed for simultaneous qualitative and quantitative analysis of five metabolites of nitrofuran antibiotics, including 3-amino-2-oxazolidinone (AOZ), 5-morpholino-methyl-3-amino-2-oxazolidinone ( AMOZ ), semicarbazide ( SEM ), 1-aminohydantoin (AHD) and 3, 5-dinitrosalicylic acid hydrazide (DNSH) in aquatic products by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The samples were hydrolyzed with HCl, and derivatized with 2-nitrobenzaldehyde at 37 degre C for 16 hours. The derivative solutions were adjusted to pH 7.0 -7. 5, and the analytes were extracted by ethyl acetate. The separation was based on Thermo Aquasil C18 column (150 mm x 4.6 mm, 3.01 micro m). The analytes were detected by tandem mass spectrometry with electrospray ionization source with multiple reaction monitoring (MRM) mode. The developed method showed good linear correlation between the peak area ratios of the analyte and the internal standard and the concentration of the analyte with the correlation coefficients all above 0. 99 over the dynamic range of 0.5 - 10 micro g/kg. The limits of quantitation (LOQs) of AOZ, AMOZ, SEM, AHD and DNSH were 0.5 micro g/kg. The average recoveries of all the compounds at four spiked levels of 0.5, 1.0, 2.0 and 4. 0 micro g/kg ranged from 81.3% to 100.5% with the RSDs between 3.4% and 10.0% (n =6). The method is proved to be fast and effective for simultaneous qualitative and quantitative analysis of the metabolites of the nitrofuran antibiotics in aquatic products. PMID:23785991

  15. Isolation of heterotrophic bacteria from Palk Bay sediments showing heavy metal tolerance and antibiotic production.

    PubMed

    Nithya, Chari; Pandian, Shunmugiah Karutha

    2010-09-20

    Analysis of culturable and unculturable bacteria and their potential bioactive compounds from Palk Bay is yet to be explored. The present study for the first time characterizes the culturable bacteria from Palk Bay sediment using 16S rRNA gene sequencing. The characterized bacteria were also screened for antibacterial activity against human and aquaculture pathogens. In the 16S rRNA gene sequence analysis characterized that most of the bacteria were affiliated to members of Firmicutes and less with Gammaproteobacteria, Actinobacteria and Alphaproteobacteria. A high portion of (39%) of the bacteria showed antibacterial activity against both Gram positive and Gram negative test strains. The antibiotics from the strain S6-05 were partially purified using solvent extraction followed by TLC and silica column and further characterized by IR analysis. Two active principles A and B showed difference in the activity against Gram positive and Gram negative pathogens. But in the synergistic application they showed excellent activity against all the test pathogens. This study provides the first evidence on the existence of certain Bacillus species in the marine environment, namely Bacillus arsenicus, Bacillus indicus, Bacillus boroniphilus, Bacillus cibi and Bacillus niabensis which also had antibacterial activity. Several of the isolates exhibited tolerance to arsenic and boron to a new level of 25 and 100 mM, respectively. The current study reveals the fact that a great deal remains in the bacterial diversity of Palk Bay region. PMID:20015629

  16. Alkaline thermal pretreatment at mild temperatures for biogas production from anaerobic digestion of antibiotic mycelial residue.

    PubMed

    Li, Chunxing; Zhang, Guangyi; Zhang, Zhikai; Ma, Dachao; Xu, Guangwen

    2016-05-01

    This paper aims at lowering the temperature for thermal pretreatment (TPT) of antibiotic mycelial residue (AMR) by alkali addition but without significantly worsening subsequent anaerobic digestion (AD) for biogas. Batch TPT and AD experiments were conducted in a bench-scale autoclave and several bench-scale anaerobic digesters, respectively. The results showed that the methane yield (<200 ml·(g VS)(-1)) was visibly lower with lowering pretreatment temperature, compared to that (290 ml·(g VS)(-1)) for TPT at the optimal temperature of 120°C, while it rebounded to 231 ml·(g VS)(-1) when proper amounts of alkali were employed (to adjust the pH of the AMR to 12) for TPT at 80°C. Further analysis indicated that low-temperature alkaline TPT was significantly less energy-consumption compared to only TPT, at cost of small amounts of alkali. It was more convenient and economical to implement AD of AMR in combination with alkaline TPT at mild temperatures for biogas. PMID:26921869

  17. Relationship of amino acid composition and molecular weight of antifreeze glycopeptides to non-colligative freezing point depression.

    PubMed

    Schrag, J D; O'Grady, S M; DeVries, A L

    1982-08-01

    Many polar fishes synthesize a group of eight glycopeptides that exhibit a non-colligative lowering of the freezing point of water. These glycopeptides range in molecular weight between 2600 and 33 700. The largest glycopeptides [1-5] lower the freezing point more than the small ones on a weight basis and contain only two amino acids, alanine and threonine, with the disaccharide galactose-N-acetyl-galactosamine attached to threonine. The small glycopeptides, 6, 7, and 8, also lower the freezing point and contain proline, which periodically substitutes for alanine. Glycopeptides with similar antifreeze properties isolated from the saffron cod and the Atlantic tomcod contain an additional amino acid, arginine, which substitutes for threonine in glycopeptide 6. In this study we address the question of whether differences in amino acid composition or molecular weight between large and small glycopeptides are responsible for the reduced freezing point depressing capability of the low molecular weight glycopeptides. The results indicate that the degree of amino acid substitutions that occur in glycopeptides 6-8 do not have a significant effect on the unusual freezing point lowering and that the observed decrease in freezing point depression with smaller glycopeptides can be accounted for on the basis of molecular weight. PMID:7115772

  18. Medium engineering for enhanced production of undecylprodigiosin antibiotic in Streptomyces coelicolor using oil palm biomass hydrolysate as a carbon source.

    PubMed

    Bhatia, Shashi Kant; Lee, Bo-Rahm; Sathiyanarayanan, Ganesan; Song, Hun-Seok; Kim, Junyoung; Jeon, Jong-Min; Kim, Jung-Ho; Park, Sung-Hee; Yu, Ju-Hyun; Park, Kyungmoon; Yang, Yung-Hun

    2016-10-01

    In this study, a biosugar obtained from empty fruit bunch (EFB) of oil palm by hot water treatment and subsequent enzymatic saccharification was used for undecylprodigiosin production, using Streptomyces coelicolor. Furfural is a major inhibitor present in EFB hydrolysate (EFBH), having a minimum inhibitory concentration (MIC) of 1.9mM, and it reduces utilization of glucose (27%), xylose (59%), inhibits mycelium formation, and affects antibiotic production. Interestingly, furfural was found to be a good activator of undecylprodigiosin production in S. coelicolor, which enhanced undecylprodigiosin production by up to 52%. Optimization by mixture analysis resulted in a synthetic medium containing glucose:furfural:ACN:DMSO (1%, 2mM, 0.2% and 0.3%, respectively). Finally, S. coelicolor was cultured in a fermenter in minimal medium with EFBH as a carbon source and addition of the components described above. This yielded 4.2μg/mgdcw undecylprodigiosin, which was 3.2-fold higher compared to that in un-optimized medium. PMID:26951741

  19. In Search of the E. coli Compounds that Change the Antibiotic Production Pattern of Streptomyces coelicolor During Inter-species Interaction.

    PubMed

    Mavituna, Ferda; Luti, Khalid Jaber Kadhum; Gu, Lixing

    2016-08-01

    The aim of this work was to investigate the interaction between E.coli and Streptomyces coelicolor A3 (2) for the increased production of undecylprodigiosin and identify the E. coli actives mediating this inter-species interaction. The antibiotics of interest were the red-pigmented undecylprodigiosin and blue-pigmented actinorhodin. Pure cultures of S. coelicolor in a defined medium produced higher concentrations of actinorhodin compared to those of undecylprodigiosin. The latter however, is more important due to its immunosuppressive and antitumor properties. As a strategy to increase undecylprodigiosin production, we added separately, live cells and heat-killed cells of E. coli C600, and the cell-free supernatant of E. coli culture to S. coelicolor cultures in shake flasks. The interaction with live cells of E. coli altered the antibiotic production pattern and undecylprodigiosin production was enhanced by 3.5-fold compared to the pure cultures of S. coelicolor and actinorhodin decreased by 15-fold. The heat-killed cells of E. coli however, had no effect on antibiotic production. In all cases, growth and glucose consumption of S. coelicolor remained almost the same as those observed in the pure culture indicating that the changes in antibiotic production were not due to nutritional stress. Results with cell-free supernatant of E. coli culture indicated that the interaction between S. coelicolor and E. coli was mediated via diffusible molecule(s). Using a set of extraction procedures and agar-well diffusion bioassays, we isolated and preliminarily identified a class of compounds. For the preliminary verification, we added the compound which was the common chemical structural moiety in this class of compounds to the pure S. coelicolor cultures. We observed similar effects on antibiotic production as with the live E. coli cells and their supernatant indicating that this class of compounds secreted by E. coli indeed could act as actives during interspecies

  20. Correlation between biofilm production, antibiotic susceptibility and exopolysaccharide composition in Burkholderia pseudomallei bpsI, ppk, and rpoS mutant strains.

    PubMed

    Mongkolrob, Rungrawee; Taweechaisupapong, Suwimol; Tungpradabkul, Sumalee

    2015-11-01

    Burkholderia pseudomallei is the cause of melioidosis, a fatal tropical infectious disease, which has been reported to have a high rate of recurrence, even when an intensive dose of antibiotics is used. Biofilm formation is believed to be one of the possible causes of relapse because of its ability to increase drug resistance. EPS in biofilms have been reported to be related to the limitation of antibiotic penetration in B. pseudomallei. However, the mechanisms by which biofilms restrict the diffusion of antibiotics remain unclear. The present study presents a correlation between exopolysaccharide production in biofilm matrix and antibiotic resistance in B. pseudomallei using bpsI, ppk, and rpoS mutant strains. CLSM revealed a reduction in exopolysaccharide production and disabled micro-colony formation in B. pseudomallei mutants, which paralleled the antibiotic resistance. Different ratios of carbohydrate contents in the exopolysaccharides of the mutants were detected, although they have the same components, including glucose, galactose, mannose, and rhamnose, with the exception being that no detectable rhamnose peak was observed in the bpsI mutant. These results indicate that the correlation between these phenomena in the B. pseudomallei biofilm at least results from the exopolysaccharide, which may be under the regulation of bpsI, ppk, or rpoS genes. PMID:26486518

  1. Facile synthesis of boronic acid-functionalized magnetic carbon nanotubes for highly specific enrichment of glycopeptides

    NASA Astrophysics Data System (ADS)

    Ma, Rongna; Hu, Junjie; Cai, Zongwei; Ju, Huangxian

    2014-02-01

    A stepwise strategy was developed to synthesize boronic acid functionalized magnetic carbon nanotubes (MCNTs) for highly specific enrichment of glycopeptides. The MCNTs were synthesized by a solvothermal reaction of Fe3+ loaded on the acid-treated CNTs and modified with 1-pyrenebutanoic acid N-hydroxysuccinimidyl ester (PASE) to bind aminophenylboronic acid (APBA) via an amide reaction. The introduction of PASE could bridge the MCNT and APBA, suppress the nonspecific adsorption and reduce the steric hindrance among the bound molecules. Due to the excellent structure of the MCNTs, the functionalization of PASE and then APBA on MCNTs was quite simple, specific and effective. The glycopeptides enrichment and separation with a magnetic field could be achieved by their reversible covalent binding with the boronic group of APBA-MCNTs. The exceptionally large specific surface area and the high density of boronic acid groups of APBA-MCNTs resulted in rapid and highly efficient enrichment of glycopeptides, even in the presence of large amounts of interfering nonglycopeptides. The functional MCNTs possessed high selectivity for enrichment of 21 glycopeptides from the digest of horseradish peroxidase demonstrated by MALDI-TOF mass spectrometric analysis showing more glycopeptides detected than the usual 9 glycopeptides with commercially available APBA-agarose. The proposed system showed better specificity for glycopeptides even in the presence of non-glycopeptides with 50 times higher concentration. The boronic acid functionalized MCNTs provide a promising selective enrichment platform for precise glycoproteomic analysis.A stepwise strategy was developed to synthesize boronic acid functionalized magnetic carbon nanotubes (MCNTs) for highly specific enrichment of glycopeptides. The MCNTs were synthesized by a solvothermal reaction of Fe3+ loaded on the acid-treated CNTs and modified with 1-pyrenebutanoic acid N-hydroxysuccinimidyl ester (PASE) to bind aminophenylboronic acid

  2. Synthesis of tumor-associated MUC1-glycopeptides and their multivalent presentation by functionalized gold colloids.

    PubMed

    Tavernaro, Isabella; Hartmann, Sebastian; Sommer, Laura; Hausmann, Heike; Rohner, Christian; Ruehl, Martin; Hoffmann-Roeder, Anja; Schlecht, Sabine

    2015-01-01

    The mucin MUC1 is a glycoprotein involved in fundamental biological processes, which can be found over-expressed and with a distinctly altered glycan pattern on epithelial tumor cells; thus it is a promising target structure in the quest for effective carbohydrate-based cancer vaccines and immunotherapeutics. Natural glycopeptide antigens indicate only a low immunogenicity and a T-cell independent immune response; however, this major drawback can be overcome by coupling of glycopeptide antigens multivalently to immunostimulating carrier platforms. In particular, gold nanoparticles are well suited as templates for the multivalent presentation of glycopeptide antigens, due to their remarkably high surface-to-volume ratio in combination with their high biostability. In this work the synthesis of novel MUC1-glycopeptide antigens and their coupling to gold nanoparticles of different sizes are presented. In addition, the development of a new dot-blot immunoassay to test the potential antigen-antibody binding is introduced. PMID:25212389

  3. Chemical Synthesis of Human Syndecan-3 Glycopeptides Bearing Two Heparan Sulfate Glycan Chains

    PubMed Central

    Yoshida, Keisuke; Yang, Bo; Yang, Weizhun; Zhang, Zeren; Zhang, Jicheng

    2014-01-01

    Despite the ubiquitous presence of proteoglycans in mammalian systems, methodologies to synthesize this class of glycopeptides with homogeneous glycans are not well developed. Herein, we report the first synthesis of glycosaminoglycan family glycopeptides containing two different heparan sulfate chains from human syndecan-3. With the large sizes and tremendous structural complexities, multiple unexpected obstacles were encountered in synthesis, which include the high sensitivity to base treatment and the instability of glycopeptides with two glycan chains towards catalytic hydrogenation conditions. To overcome these challenges, after many trials, a successful strategy was established by constructing the partially deprotected single glycan chain containing glycopeptides first followed by union of the glycan bearing fragments and cleavage of ester type protecting groups. This work has laid the foundation to prepare other members of this important class of molecules. PMID:24981920

  4. Diversity, Distribution and Quantification of Antibiotic Resistance Genes in Goat and Lamb Slaughterhouse Surfaces and Meat Products

    PubMed Central

    Lavilla Lerma, Leyre; Benomar, Nabil; Knapp, Charles W.; Correa Galeote, David; Gálvez, Antonio; Abriouel, Hikmate

    2014-01-01

    The distribution and quantification of tetracycline, sulfonamide and beta-lactam resistance genes were assessed in slaughterhouse zones throughout meat chain production and the meat products; this study represents the first to report quantitatively monitor antibiotic resistance genes (ARG) in goat and lamb slaughterhouse using a culture independent approach, since most studies focused on individual bacterial species and their specific resistance types. Quantitative PCR (qPCR) revealed a high prevalence of tetracycline resistance genes tetA and tetB in almost all slaughterhouse zones. Sulfonamide resistance genes were largely distributed, while beta-lactam resistance genes were less predominant. Statistical analysis revealed that resistant bacteria, in most cases, were spread by the same route in almost all slaughterhouse zones, except for tetB, blaCTX and blaTEM genes, which occurred in few zones as isolated ‘hot spots.’ The sum of all analyzed ARG indicated that slaughterhouse surfaces and end products act as reservoirs of ARG, mainly tet genes, which were more prevalent in slaughtering room (SR), cutting room (CR) and commercial meat products (MP). Resistance gene patterns suggest they were disseminated throughout slaughterhouse zones being also detected in commercial meat products, with significant correlations between different sampling zones/end products and total resistance in SR, CR and white room (WR) zones, and also refrigerator 4 (F4) and MP were observed. Strategically controlling key zones in slaughterhouse (SR, CR and WR) by adequate disinfection methods could strategically reduce the risks of ARG transmission and minimize the issues of food safety and environment contamination. PMID:25479100

  5. [Evolution of the concept of residues in the products of animals raised with the use of antibiotics].

    PubMed

    Wal, J M

    1979-01-01

    The concept of residues of antibiotics used as feed additives or veterinary drugs in food producing animals is analysed, and implications on human public health are discussed. The examples of Tylosin and Penicillin are developed to illustrate the both notions of "high risk residue" and "toxicodisponibility" of residues. The "high risk residue" may be an active metabolite different by its chemical structure and by its pharmacological properties from the original drug administered. Slight modifications of the molecule, as the rupture of the beta lactam ring of the Penicillin, occuring in vivo, lead to a metabolite, e.g. penicilloyl group, that has lost all antibiotic activity but possesses allergenic potential. Toxicity of the residue, compared with that of the original drug, can then be modified or increased. On the other hand, such an active metabolite having a definite chemical structure, even if different from the original compound, can be present in the organism, either free or bound to serum or tissues proteins. Moreover, it is shown here, that in the case of a covalent binding of the drug or its metabolite (e.g. penicilloyl group) to serum albumin, the residues are mostly masked inside the tertiary structure of the albumin molecule, and are not accessible to antibodies. These different forms have then an effect upon the biodisponibility, the "toxicodisponibility", of the residues for the human consumer of animal products where they are present. These forms are only accessible with more and more specific and sensitive analytical methods which relates also the qualitative and quantitative notions of residue to the technological degree used for investigation, determination and identification. As to cooking techniques, they can lead to a thermodegradation of the residue or, on the opposite, to an unmasking of the residue present as a protein conjugate, e.g. penicilloyl-protein conjugate in milk. PMID:533076

  6. Variations in the fecal occurrences of antimicrobial-resistant bacteria are greater between seasons than between "raised without antibiotics" and "conventional" cattle production systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to compare, over a year, fecal occurrences of antimicrobial-resistant bacteria (ARB) in fed-cattle between two production systems: "raised without antibiotics" (RWA) and “conventional” (CONV). Feces were recovered from colons at a commercial beef processing plant obta...

  7. Magnetic nanoparticles coated with maltose-functionalized polyethyleneimine for highly efficient enrichment of N-glycopeptides.

    PubMed

    Li, Jinan; Wang, Fangjun; Wan, Hao; Liu, Jing; Liu, Zheyi; Cheng, Kai; Zou, Hanfa

    2015-12-18

    Hydrophilic interaction chromatography (HILIC) adsorbents have drawn increasing attention in recent years due to their high efficiency in N-glycopeptides enrichment. The hydrophilicity and binding capacity of HILIC adsorbents are crucial to the enrichment efficiency and mass spectrometry (MS) detection sensitivity of N-glycopeptides. Herein, magnetic nanoparticles coated with maltose-functionalized polyethyleneimine (Fe3O4-PEI-Maltose MNPs) were prepared by one-pot solvothermal reaction coupled with "click chemistry" and utilized for N-glycopeptides enrichment. Owing to the presence of hydrophilic and branched polyethyleneimine, the amount of immobilized disaccharide units was improved about four times. The N-glycopeptides capturing capacity was about 150mg/g (IgG/MNPs) and the MS detection limitation as low as 0.5fmol for IgG and 85% average enrichment recovery were feasibly achieved by using this hybrid magnetic adsorbent. Finally, 1237 unique N-glycosylation sites and 1567 unique N-glycopeptides from 684 N-glycoproteins were reliably characterized from 60μg protein sample extracted from mouse liver. Therefore, this maltose-functionalized polyethyleneimine coated adsorbent can play a promising role in highly efficient N-glycopeptides enrichment for glycoproteomic analyses of complex protein samples. PMID:26607318

  8. Characterization of Protein N-Glycosylation by Analysis of ZIC-HILIC-Enriched Intact Proteolytic Glycopeptides.

    PubMed

    Pohlentz, Gottfried; Marx, Kristina; Mormann, Michael

    2016-01-01

    Zwitterionic hydrophilic interaction chromatography (ZIC-HILIC) solid-phase extraction (SPE) combined with direct-infusion nanoESI mass spectrometry (MS) and tandem MS/MS is a well-suited method for the analysis of protein N-glycosylation. A site-specific characterization of N-glycopeptides is achieved by the combination of proteolytic digestions employing unspecific proteases, glycopeptide enrichment by use of ZIC-HILIC SPE, and subsequent mass spectrometric analysis. The use of thermolysin or a mixture of trypsin and chymotrypsin leads per se to a mass-based separation, that is, small nonglycosylated peptides and almost exclusively glycopeptides at higher m/z values. As a result of their higher hydrophilicity N-glycopeptides comprising short peptide backbones are preferably accumulated by the ZIC-HILIC-based separation procedure. By employing this approach complications associated with low ionization efficiencies of N-glycopeptides resulting from signal suppression in the presence of highly abundant nonglycosylated peptides can be largely reduced. Here, we describe a simple protocol aimed at the enrichment of N-glycopeptides derived from in-solution and in-gel digestions of SDS-PAGE-separated glycoproteins preceding mass spectrometric analysis. PMID:26700048

  9. Complex marine natural products as potential epigenetic and production regulators of antibiotics from a marine Pseudomonas aeruginosa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Marine microbes are capable of producing secondary metabolites for defense and competition. Factors exerting an impact on secondary metabolite production of microbial communities included bioactive natural products and co-culturing. These external influences may have practical applications such as ...

  10. [Investigation of the serotype distribution, biofilm production and antibiotic susceptibilities of group B streptococci isolated from urinary samples].

    PubMed

    Baba, Sevinç; Aydın, Mustafa Derya

    2016-07-01

    Streptococcus agalactiae (Group B streptococcus, GBS), a member of normal flora of human gastrointestinal and genitourinary systems, is a leading cause of sepsis, meningitis, and pneumonia particularly in newborn. GBS can also cause severe infections in pregnant women and adults with underlying disease, as well as mild diseases, such as urinary tract infections (UTIs). GBS strains exhibit 10 different serotypes, and the identification of serotype distribution is important epidemiologically. The role of biofilm production is one of the virulence factors that has been discussed in the pathogenesis of GBS infections. Although resistance to penicillin and ampicillin has not been documented in GBS, different rates of resistance has been reported for the alternative antibiotics to penicillin. The aim of this study was to investigate the serotype distribution, the ability of biofilm formation and the antibiotic susceptibilities of S.agalactiae strains isolated from urine cultures. A total of 60 strains were included in the study, 40 of them were isolated from patients (38 female 2 male; mean age: 36.7 years) with urinary tract complaints whose cultures yielded single type of colonies in the number of ≥ 50.000 cfu/ml, whereas 20 of them were isolated from patients (19 female 1 male; mean age: 37.2 years) without urinary tract complaints whose cultures yielded mixed colonies in the number of ≤ 20.000 cfu/ml. Chromogenic media were used for the isolation and the isolates were identified by conventional methods. The isolates were then serotyped by latex agglutination method and their antibiotic susceptibilities were determined by disk diffusion method recommended by CLSI documents. Biofilm formation of the strains were investigated by microplate and Congo red agar (CRA) methods. In our study, the most frequently detected serotypes were V (n= 18; 30%) and II (n= 14; 23.3%), followed by serotype Ia (n= 10; 16.7%), III (n= 9; 15%), Ib (n= 3; 5%), VI (n= 1; 1.7%) and VII (n

  11. Outbreak of Achromobacter xylosoxidans in an Italian Cystic fibrosis center: genome variability, biofilm production, antibiotic resistance, and motility in isolated strains

    PubMed Central

    Trancassini, Maria; Iebba, Valerio; Citerà, Nicoletta; Tuccio, Vanessa; Magni, Annarita; Varesi, Paola; De Biase, Riccardo V.; Totino, Valentina; Santangelo, Floriana; Gagliardi, Antonella; Schippa, Serena

    2014-01-01

    Cystic fibrosis (CF) patients have chronic airway infection and frequent exposure to antibiotics, which often leads to the emergence of resistant organisms. Achromobacter xylosoxidans is a new emergent pathogen in CF spectrum. From 2005 to 2010 we had an outbreak in A. xylosoxidans prevalence in our CF center, thus, the present study was aimed at deeply investigating virulence traits of A. xylosoxidans strains isolated from infected CF patients. To this purpose, we assessed A. xylosoxidans genome variability by randomly amplified polymorphic DNA (RAPD), biofilm production, antibiotic resistances, and motility. All A. xylosoxidans strains resulted to be biofilm producers, and were resistant to antibiotics usually employed in CF treatment. Hodge Test showed the ability to produce carbapenemase in some strains. Strains who were resistant to β-lactamics antibiotics, showed the specific band related to metal β-lactamase (blaIMP-1), and some of them showed to possess the integron1. Around 81% of A. xylosoxidans strains were motile. Multivariate analysis showed that RAPD profiles were able to predict Forced Expiratory Volume (FEV1%) and biofilm classes. A significant prevalence of strong biofilm producers strains was found in CF patients with severely impaired lung functions (FEV1% class 1). The outbreak we had in our center (prevalence from 8.9 to 16%) could be explained by an enhanced adaptation of A. xylosoxidans in the nosocomial environment, despite of aggressive antibiotic regimens that CF patients usually undergo. PMID:24772108

  12. Antibiotic-free production of a herpes simplex virus 2 DNA vaccine in a high yield cGMP process

    PubMed Central

    Nelson, Jared; Rodriguez, Stephen; Finlayson, Neil; Williams, Jim; Carnes, Aaron

    2013-01-01

    Two DNA vaccine plasmids encoding Herpes simplex virus type 2 (HSV-2) glycoprotein D, NTC8485-O2-gD2 and NTC8485-O2-UgD2tr, were produced at large scale under current good manufacturing practice (cGMP) for use in a Phase I human clinical trial. These DNA vaccines incorporate the regulatory agency compliant, minimal, antibiotic-free (AF) NTC8485 mammalian expression vector. Plasmid yields of > 1 g/L were achieved using the HyperGRO™ fed-batch fermentation process, with successful scale up from 10 L process development scale to 320 L culture volume for cGMP production. The DNA vaccines were purified using a low residence time, high shear lysis process and AIRMIXTM technology, followed by chromatographic purification. This combination of optimized plasmid vector, high yield upstream production, and efficient downstream purification resulted in purified HSV-2 DNA vaccines with > 99% total supercoiled plasmid, ≤ 0.2% RNA, ≤ 0.1% host cell genomic DNA, and ≤ 0.1 endotoxin units per mg. PMID:23899469

  13. Suppression of the toxicity of Bac7 (1-35), a bovine peptide antibiotic, and its production in E. coli.

    PubMed

    Ishida, Yojiro; Inouye, Masayori

    2016-03-01

    Bac7 (1-35) is an Arg- and Pro-rich peptide antibiotic, produced in bovine cells to protect them from microbial infection. It has been demonstrated to inhibit the protein synthesis in E. coli, leading to cell death. Because of its toxicity, no cost effective methods have been developed for Bac7 production in Escherichia coli for its potential clinical use. Here, we found a method to suppress Bac7 (1-35) toxicity in E. coli to establish its high expression system, in which Bac7 (1-35) was fused to the C-terminal end of protein S, a major spore-coat protein from Myxococcus xanthus, using a linker containing a Factor Xa cleavage site. The resulting His6-PrS2-Bac7 (1-35) (PrS2 is consisted of two N-terminal half domains of protein S connected in tandem) was well expressed using the Single-Protein Production (SPP) system at low temperature and subsequently purified in a single step by using a Ni column. The combination of protein S fusion and its expression in the SPP system at low temperature appeared to suppress Bac7 (1-35) toxicity. Both the purified His6-PrS2-Bac7 (1-35) and His6-PrS2-Bac7 (1-35) treated by Factor Xa were proven to be a potent inhibitor for cell-free protein synthesis. PMID:26936849

  14. Monitoring and determination of sulfonamide antibiotics (sulfamethoxydiazine, sulfamethazine, sulfamethoxazole and sulfadiazine) in imported Pangasius catfish products in Thailand using liquid chromatography coupled with tandem mass spectrometry.

    PubMed

    Jansomboon, Worawat; Boontanon, Suwanna Kitpati; Boontanon, Narin; Polprasert, Chongrak; Thi Da, Chau

    2016-12-01

    This research aimed to monitor the concentrations of sulfamethoxydiazine (SMD), sulfamethazine (SMT), sulfamethoxazole (SMX) and sulfadiazine (SDZ) in imported Pangasius catfish products in Thailand. The residues of the four sulfonamides (SAs) were analyzed by extraction process and liquid chromatography coupled with tandem mass spectrometry. The highest concentrations found were 10.97ng/g for SMD, 6.23ng/g for SMT, 11.13ng/g for SDZ and 245.91ng/g for SMX, which was higher than the European Union (EU) standard (100ng/g). Moreover, all samples contaminated with SMX also contained SMT, indicating that more than one antibiotic was used for production in the country of origin. Because Thai standards for antibiotics in food have not been completely set, all contaminated discovered would not be considered to be an illegal food, in which antibiotic residues may affect human health in the long term. Therefore, antibiotic residues in Pangasius catfish products should be continually regulated and monitored. PMID:27374578

  15. Work plan for determining the occurrence of glyphosate, its transformation product AMPA, other herbicide compounds, and antibiotics in midwestern United States streams, 2002

    USGS Publications Warehouse

    Battaglin, W.A.; Thurman, E.M.; Kolpin, D.W.; Scribner, E.A.; Sandstrom, M.W.; Kuivila, K.M.

    2003-01-01

    The objective of this study is to determine the distribution of glyphosate and its primary transformation product aminomethylphosphonic acid (AMPA) in midwestern streams during post-application and harvest-season runoff events. Water samples will be collected in 2002 during two post-herbicide-application runoff events and one harvest-season runoff event from 53 sites on streams in the Midwestern United States. All samples will be analyzed at the U.S. Geological Survey Organic Geochemistry Research Laboratory in Lawrence, Kansas, for glyphosate and 20 other herbicides. Samples will also be analyzed for a glyphosate transformation product (AMPA) and 26 other herbicide transformation products, using GC/MS or HPLC/MS. Selected samples will be analyzed for 36 antibiotics or antibiotic transformational products. Results from this study will represent the first broad-scale investigation of glyphosate and AMPA in U.S. water resources.

  16. Growth and survival of antibiotic-resistant Salmonella typhimurium DT104 in liquid egg products.

    PubMed

    Musgrove, Michael T; Mcquestin, Olivia J; Tamplin, Mark; Kelley, Lynda C

    2009-09-01

    Since 11 September 2001, quality and food safety are no longer the concerns of only consumers, industry, regulatory agencies, or other government officials. Liquid foods that are prepared or stored in bulk, including liquid egg products, are considered to be at potential risk for sabotage. Because of their versatility, low price, and functional properties, many of these products are being marketed. Four of the most common products of this type are whole egg, egg albumen, 10% sugared yolk, and 10% salted yolk. Although all of the serotypes of Salmonella enterica may cause illness, multidrug-resistant Salmonella Typhimurium DT104 has become widespread and can cause severe illness that is difficult to treat. Studies were conducted to determine growth patterns of Salmonella Typhimurium DT104 in four commercial liquid egg products held at 4, 10, 20, 30, 37, and 42 degrees C for 0 to 384 h. All experiments were performed in duplicate and repeated twice. Standard methods were used to estimate cell numbers, and log CFU per gram of egg product was plotted against time. The number of cells of Salmonella Typhimurium DT104 increased to 8 to 9 log CFU/g in whole egg and 10% sugared yolk, increased by 1 log CFU/g in liquid albumen, but decreased by 3 log CFU/g in 10% salted yolk. Data from this study have been archived in the ComBase database to further assist policy makers or other scientists interested in Salmonella growth characteristics in liquid eggs. However, based on data generated in this study, Salmonella Typhimurium DT104 probably does not constitute a food threat agent in liquid eggs. PMID:19777905

  17. Antibiotic alternatives: the substitution of antibiotics in animal husbandry?

    PubMed Central

    Cheng, Guyue; Hao, Haihong; Xie, Shuyu; Wang, Xu; Dai, Menghong; Huang, Lingli; Yuan, Zonghui

    2014-01-01

    It is a common practice for decades to use of sub-therapeutic dose of antibiotics in food-animal feeds to prevent animals from diseases and to improve production performance in modern animal husbandry. In the meantime, concerns over the increasing emergence of antibiotic-resistant bacteria due to the unreasonable use of antibiotics and an appearance of less novelty antibiotics have prompted efforts to develop so-called alternatives to antibiotics. Whether or not the alternatives could really replace antibiotics remains a controversial issue. This review summarizes recent development and perspectives of alternatives to antibiotics. The mechanism of actions, applications, and prospectives of the alternatives such as immunity modulating agents, bacteriophages and their lysins, antimicrobial peptides, pro-, pre-, and synbiotics, plant extracts, inhibitors targeting pathogenicity (bacterial quorum sensing, biofilm, and virulence), and feeding enzymes are thoroughly discussed. Lastly, the feasibility of alternatives to antibiotics is deeply analyzed. It is hard to conclude that the alternatives might substitute antibiotics in veterinary medicine in the foreseeable future. At the present time, prudent use of antibiotics and the establishment of scientific monitoring systems are the best and fastest way to limit the adverse effects of the abuse of antibiotics and to ensure the safety of animal-derived food and environment. PMID:24860564

  18. Simultaneous production of alkaline lipase and protease by antibiotic and heavy metal tolerant Pseudomonas aeruginosa.

    PubMed

    Bisht, Deepali; Yadav, Santosh Kumar; Gautam, Pallavi; Darmwal, Nandan Singh

    2013-09-01

    An efficient bacterial strain capable of simultaneous production of lipase and protease in a single production medium was isolated. Thirty six bacterial strains, isolated from diverse habitats, were screened for their lipolytic and proteolytic activity. Of these, only one bacterial strain was found to be lipase and protease producer. The 16S rDNA sequencing and phylogenetic analyses revealed that strain (NSD-09) was in close identity to Pseudomonas aeruginosa. The maximum lipase (221.4 U/ml) and protease (187.9 U/ml) activities were obtained after 28 and 24 h of incubation, respectively at pH 9.0 and 37 °C. Castor oil and wheat bran were found to be the best substrate for lipase and protease production, respectively. The strain also exhibited high tolerance to lead (1450 µg/ml) and chromium (1000 µg/ml) in agar plates. It also showed tolerance to other heavy metals, such as Co(+2) , Zn(+2) , Hg(+2) , Ni(+2) and Cd(+2) . Therefore, this strain has scope for tailing bioremediation. Presumably, this is the first attempt on P. aeruginosa to explore its potential for both industrial and environmental applications. PMID:22961768

  19. Contribution of enterococci to the spread of antibiotic resistance in the production chain of swine meat commodities.

    PubMed

    Rizzotti, Lucia; Simeoni, Desj; Cocconcelli, Piersandro; Gazzola, Simona; Dellaglio, Franco; Torriani, Sandra

    2005-05-01

    Thirty-six samples, including fecal specimens, dry feedstuffs, raw and processed pork meat products, and dry fermented sausages, were collected from two production chains of swine meat commodities and analyzed for the presence of 11 antibiotic resistance (AR) genes. Specific PCR assays carried out on DNA extracted directly from the samples revealed a high incidence of the genes tet(K) (80.5%), ermB (66.7%), and tet(M) (66.7%). Feces and feedstuffs gave the largest number of positive amplifications. To elucidate the contribution of enterococci to the occurrence and spread of AR, 146 resistant enterococci were isolated, and their identity, genetic fingerprints, and AR gene profiles were determined by means of molecular techniques. Enterococcus faecalis and Enterococcus faecium were the predominant isolated species (43.8 and 38.4%, respectively); Other Enterococcus species identified were E. durans (8.9%), E. hirae (2.7%), E. gallinarum (2.1%), E. mundtii (2.1%), and E. casseliflavus (2.1%). A number of isolates displayed a complex AR gene profile comprising up to four different resistance determinants. The genes tet(M) and ermB were highly diffused, being present in 86.9 and 84.9%, respectively, of the isolates. The application of amplified fragment length polymorphism fingerprinting was particularly valuable to monitor the resistant enterococcal isolates along the production chain and to individuate steps in which contamination might occur. In fact, isolates of E. faecalis and E. faecium showing the same amplified fragment length polymorphism profile and AR gene pattern were detected in samples taken at different steps of the food chain suggesting three cases of bacterial clonal spread. PMID:15895727

  20. Hydrazide functionalized core-shell magnetic nanocomposites for highly specific enrichment of N-glycopeptides.

    PubMed

    Liu, Liting; Yu, Meng; Zhang, Ying; Wang, Changchun; Lu, Haojie

    2014-05-28

    In view of the biological significance of glycosylation for human health, profiling of glycoproteome from complex biological samples is highly inclined toward the discovery of disease biomarkers and clinical diagnosis. Nevertheless, because of the existence of glycopeptides at relatively low abundances compared with nonglycosylated peptides and glycan microheterogeneity, glycopeptides need to be highly selectively enriched from complex biological samples for mass spectrometry analysis. Herein, a new type of hydrazide functionalized core-shell magnetic nanocomposite has been synthesized for highly specific enrichment of N-glycopeptides. The nanocomposites with both the magnetic core and the polymer shell hanging high density of hydrazide groups were prepared by first functionalization of the magnetic core with polymethacrylic acid by reflux precipitation polymerization to obtain the Fe3O4@poly(methacrylic acid) (Fe3O4@PMAA) and then modification of the surface of Fe3O4@PMAA with adipic acid dihydrazide (ADH) to obtain Fe3O4@poly(methacrylic hydrazide) (Fe3O4@PMAH). The abundant hydrazide groups toward highly specific enrichment of glycopeptides and the magnetic core make it suitable for large-scale, high-throughput, and automated sample processing. In addition, the hydrophilic polymer surface can provide low nonspecific adsorption of other peptides. Compared to commercially available hydrazide resin, Fe3O4@PMAH improved more than 5 times the signal-to-noise ratio of standard glycopeptides. Finally, this nanocomposite was applied in the profiling of N-glycoproteome from the colorectal cancer patient serum. In total, 175 unique glycopeptides and 181 glycosylation sites corresponding to 63 unique glycoproteins were identified in three repeated experiments, with the specificities of the enriched glycopeptides and corresponding glycoproteins of 69.6% and 80.9%, respectively. Because of all these attractive features, we believe that this novel hydrazide functionalized

  1. Selection of an Antibiotic-Hypersusceptible Mutant of Pseudomonas aeruginosa: Identification of the GlmR Transcriptional Regulator

    PubMed Central

    Ramos-Aires, Julio; Plésiat, Patrick; Kocjancic-Curty, Lasta; Köhler, Thilo

    2004-01-01

    Tn501 random mutagenesis was applied to the Pseudomonas aeruginosa wild-type strain PAO1 to select for mutants hypersusceptible to aminoglycoside antimicrobial agents. One such mutant, called 19A, was found to be hypersusceptible to a wide range of antibiotics including aminoglycosides, β-lactams, fluoroquinolones, colistin, erythromycin, rifampin, and glycopeptides. Light microscopy of the mutant strain revealed abnormal morphology characterized by large, filamentous cells. The drug supersusceptibility of 19A was accompanied by loss of motility, reduced resistance to osmotic and heat shock stress, and impaired growth at low temperatures. The insertion site of the Tn501 transposon in mutant 19A has occurred in an open reading frame (PA5550 according to the PAO1 genome project), whose gene product shows amino acid sequence similarity to the DeoR family of transcriptional repressors. The gene, which we called glmR, is located between the glmS (PA5549) and glmU (PA5552) homologues of E. coli, responsible for the synthesis of UDP-N-acetylglucosamine-1-P, a precursor of both lipopolysaccharide (LPS) and peptidoglycan. We showed that GlmR represses the transcription of the adjacent glmS homologue (PA5549) in P. aeruginosa, possibly affecting the pool of precursors for peptidoglycan and LPS synthesis. To our knowledge GlmR is the first regulator in P. aeruginosa that affects susceptibility to a large variety of antibiotics and is therefore a potential target for novel anti-infective agents. PMID:14982774

  2. New antimicrobial molecules and new antibiotic strategies.

    PubMed

    Rodríguez de Castro, Felipe; Naranjo, Olga Rajas; Marco, Javier Aspa; Violán, Jordi Solé

    2009-04-01

    Drug options for treatment of infections are increasingly limited. The pharmaceutical industry has found it difficult to discover new antimicrobial agents, and only two novel classes of antibiotics, the oxazolidinones and the cyclic lipopeptides, have entered the market since the late 1960s. Few new agents have reached the market in the last decade with potential interest for community-acquired pneumonia (CAP) treatment, including linezolid (the first oxazolidinone in clinical use), new fluoroquinolones, cefditoren, ertapenem, and telithromycin. Agents currently in clinical development include other novel quinolones and ketolides, broad-spectrum cephalosporin derivatives, faropenem, several glycopeptides, and iclaprim. Other molecules are considered to be promising candidates for the future. In addition to the foregoing agents, alternative treatment approaches have also been introduced into clinical practice, which include the administration of the appropriate antimicrobials in a timely manner and the consideration of the pharmacokinetic-pharmacodynamic properties of the agent(s). PMID:19296416

  3. Genome Sequence of the Bacterium Streptomyces davawensis JCM 4913 and Heterologous Production of the Unique Antibiotic Roseoflavin

    PubMed Central

    Jankowitsch, Frank; Schwarz, Julia; Rückert, Christian; Gust, Bertolt; Szczepanowski, Rafael; Blom, Jochen; Pelzer, Stefan; Kalinowski, Jörn

    2012-01-01

    Streptomyces davawensis JCM 4913 synthesizes the antibiotic roseoflavin, a structural riboflavin (vitamin B2) analog. Here, we report the 9,466,619-bp linear chromosome of S. davawensis JCM 4913 and a 89,331-bp linear plasmid. The sequence has an average G+C content of 70.58% and contains six rRNA operons (16S-23S-5S) and 69 tRNA genes. The 8,616 predicted protein-coding sequences include 32 clusters coding for secondary metabolites, several of which are unique to S. davawensis. The chromosome contains long terminal inverted repeats of 33,255 bp each and atypical telomeres. Sequence analysis with regard to riboflavin biosynthesis revealed three different patterns of gene organization in Streptomyces species. Heterologous expression of a set of genes present on a subgenomic fragment of S. davawensis resulted in the production of roseoflavin by the host Streptomyces coelicolor M1152. Phylogenetic analysis revealed that S. davawensis is a close relative of Streptomyces cinnabarinus, and much to our surprise, we found that the latter bacterium is a roseoflavin producer as well. PMID:23043000

  4. [Antibiotic pharmacoeconomics].

    PubMed

    Jahnz-Rózyk, Karina

    2008-11-01

    Today more than ever, doctors in the ambulatory care and hospitals must effectively manage the use of antibiotics to control costs and preserve their usefulness. To achieve this goal, antibiotic management must evolve from simplistic antibiotic cost containment to more complex, appropriate use program that are founded on clinical outcomes-based pharmacoeconomic analyses. The successful application of pharmacoeconomic principles to antimicrobial therapy requires maximizing therapeutic effectiveness while minimizing costs, with the primary on pharmacokinetic considerations. This article reviews the various pharmacoeconomic factors that affect antibiotic costs in relation to patients and institutions. Cost-effectiveness studies of macrolides in pulmonary infections are presented in this study to illustrate the utility of these analyses. PMID:19177784

  5. Antibiotics Quiz

    MedlinePlus

    ... Viruses b) Bacteria c) Viruses and Bacteria 2. Bacteria are germs that cause colds and flu. a) ... The Flu c) Cold d) Strep Throat 4. Bacteria that cause infections can become resistant to antibiotics. ...

  6. GPQuest: A Spectral Library Matching Algorithm for Site-Specific Assignment of Tandem Mass Spectra to Intact N-glycopeptides.

    PubMed

    Toghi Eshghi, Shadi; Shah, Punit; Yang, Weiming; Li, Xingde; Zhang, Hui

    2015-01-01

    Glycoprotein changes occur in not only protein abundance but also the occupancy of each glycosylation site by different glycoforms during biological or pathological processes. Recent advances in mass spectrometry instrumentation and techniques have facilitated analysis of intact glycopeptides in complex biological samples by allowing the users to generate spectra of intact glycopeptides with glycans attached to each specific glycosylation site. However, assigning these spectra, leading to identification of the glycopeptides, is challenging. Here, we report an algorithm, named GPQuest, for site-specific identification of intact glycopeptides using higher-energy collisional dissociation (HCD) fragmentation of complex samples. In this algorithm, a spectral library of glycosite-containing peptides in the sample was built by analyzing the isolated glycosite-containing peptides using HCD LC-MS/MS. Spectra of intact glycopeptides were selected by using glycan oxonium ions as signature ions for glycopeptide spectra. These oxonium-ion-containing spectra were then compared with the spectral library generated from glycosite-containing peptides, resulting in assignment of each intact glycopeptide MS/MS spectrum to a specific glycosite-containing peptide. The glycan occupying each glycosite was determined by matching the mass difference between the precursor ion of intact glycopeptide and the glycosite-containing peptide to a glycan database. Using GPQuest, we analyzed LC-MS/MS spectra of protein extracts from prostate tumor LNCaP cells. Without enrichment of glycopeptides from global tryptic peptides and at a false discovery rate of 1%, 1008 glycan-containing MS/MS spectra were assigned to 769 unique intact N-linked glycopeptides, representing 344 N-linked glycosites with 57 different N-glycans. Spectral library matching using GPQuest assigns the HCD LC-MS/MS generated spectra of intact glycopeptides in an automated and high-throughput manner. Additionally, spectral library

  7. More than anticipated - production of antibiotics and other secondary metabolites by Bacillus amyloliquefaciens FZB42.

    PubMed

    Chen, Xiao-Hua; Koumoutsi, Alexandra; Scholz, Romy; Borriss, Rainer

    2009-01-01

    The genome of environmental Bacillus amyloliquefaciens FZB42 harbors numerous gene clusters involved in synthesis of antifungal and antibacterial acting secondary metabolites. Five gene clusters, srf, bmy, fen, nrs, dhb, covering altogether 137 kb, direct non-ribosomal synthesis of the cyclic lipopeptides surfactin, bacillomycin, fengycin, an unknown peptide, and the iron siderophore bacillibactin. Bacillomycin and fengycin were shown to act against phytopathogenic fungi in a synergistic manner. Three gene clusters, mln, bae, and dif, with a total length of 199 kb were shown to direct synthesis of the antibacterial acting polyketides macrolactin, bacillaene, and difficidin. Both, non-ribosomal synthesis of cyclic lipopeptides and synthesis of polyketides are dependent on the presence of a functional sfp gene product, 4'-phosphopantetheinyl transferase, as evidenced by knockout mutation of the sfp gene resulting in complete absence of all those eight compounds. In addition, here we present evidence that a gene cluster encoding enzymes involved in synthesis and export of the antibacterial acting dipeptide bacilysin is also functional in FZB42. In summary, environmental FZB42 devoted about 340 kb, corresponding to 8.5% of its total genetic capacity, to synthesis of secondary metabolites useful to cope with other competing microorganisms present in the plant rhizosphere. PMID:18957859

  8. Investigation of ovarian cancer associated sialylation changes in N-linked glycopeptides by quantitative proteomics

    PubMed Central

    2012-01-01

    Background In approximately 80% of patients, ovarian cancer is diagnosed when the patient is already in the advanced stages of the disease. CA125 is currently used as the marker for ovarian cancer; however, it lacks specificity and sensitivity for detecting early stage disease. There is a critical unmet need for sensitive and specific routine screening tests for early diagnosis that can reduce ovarian cancer lethality by reliably detecting the disease at its earliest and treatable stages. Results In this study, we investigated the N-linked sialylated glycopeptides in serum samples from healthy and ovarian cancer patients using Lectin-directed Tandem Labeling (LTL) and iTRAQ quantitative proteomics methods. We identified 45 N-linked sialylated glycopeptides containing 46 glycosylation sites. Among those, ten sialylated glycopeptides were significantly up-regulated in ovarian cancer patients’ serum samples. LC-MS/MS analysis of the non-glycosylated peptides from the same samples, western blot data using lectin enriched glycoproteins of various ovarian cancer type samples, and PNGase F (+/−) treatment confirmed the sialylation changes in the ovarian cancer samples. Conclusion Herein, we demonstrated that several proteins are aberrantly sialylated in N-linked glycopeptides in ovarian cancer and detection of glycopeptides with abnormal sialylation changes may have the potential to serve as biomarkers for ovarian cancer. PMID:22856521

  9. Discrimination of epimeric glycans and glycopeptides using IM-MS and its potential for carbohydrate sequencing

    NASA Astrophysics Data System (ADS)

    Both, P.; Green, A. P.; Gray, C. J.; Šardzík, R.; Voglmeir, J.; Fontana, C.; Austeri, M.; Rejzek, M.; Richardson, D.; Field, R. A.; Widmalm, G.; Flitsch, S. L.; Eyers, C. E.

    2014-01-01

    Mass spectrometry is the primary analytical technique used to characterize the complex oligosaccharides that decorate cell surfaces. Monosaccharide building blocks are often simple epimers, which when combined produce diastereomeric glycoconjugates indistinguishable by mass spectrometry. Structure elucidation frequently relies on assumptions that biosynthetic pathways are highly conserved. Here, we show that biosynthetic enzymes can display unexpected promiscuity, with human glycosyltransferase pp-α-GanT2 able to utilize both uridine diphosphate N-acetylglucosamine and uridine diphosphate N-acetylgalactosamine, leading to the synthesis of epimeric glycopeptides in vitro. Ion-mobility mass spectrometry (IM-MS) was used to separate these structures and, significantly, enabled characterization of the attached glycan based on the drift times of the monosaccharide product ions generated following collision-induced dissociation. Finally, ion-mobility mass spectrometry following fragmentation was used to determine the nature of both the reducing and non-reducing glycans of a series of epimeric disaccharides and the branched pentasaccharide Man3 glycan, demonstrating that this technique may prove useful for the sequencing of complex oligosaccharides.

  10. Endocytosis of Nanomedicines: The Case of Glycopeptide Engineered PLGA Nanoparticles

    PubMed Central

    Vilella, Antonietta; Ruozi, Barbara; Belletti, Daniela; Pederzoli, Francesca; Galliani, Marianna; Semeghini, Valentina; Forni, Flavio; Zoli, Michele; Vandelli, Maria Angela; Tosi, Giovanni

    2015-01-01

    The success of nanomedicine as a new strategy for drug delivery and targeting prompted the interest in developing approaches toward basic and clinical neuroscience. Despite enormous advances on brain research, central nervous system (CNS) disorders remain the world’s leading cause of disability, in part due to the inability of the majority of drugs to reach the brain parenchyma. Many attempts to use nanomedicines as CNS drug delivery systems (DDS) were made; among the various non-invasive approaches, nanoparticulate carriers and, particularly, polymeric nanoparticles (NPs) seem to be the most interesting strategies. In particular, the ability of poly-lactide-co-glycolide NPs (PLGA-NPs) specifically engineered with a glycopeptide (g7), conferring to NPs’ ability to cross the blood brain barrier (BBB) in rodents at a concentration of up to 10% of the injected dose, was demonstrated in previous studies using different routes of administrations. Most of the evidence on NP uptake mechanisms reported in the literature about intracellular pathways and processes of cell entry is based on in vitro studies. Therefore, beside the particular attention devoted to increasing the knowledge of the rate of in vivo BBB crossing of nanocarriers, the subsequent exocytosis in the brain compartments, their fate and trafficking in the brain surely represent major topics in this field. PMID:26102358

  11. Adsorption to ice of fish antifreeze glycopeptides 7 and 8.

    PubMed Central

    Knight, C A; Driggers, E; DeVries, A L

    1993-01-01

    Experimental results show that fish antifreeze glycopeptides (AFGPs) 8 and 7 (with 4 and 5 repeats respectively of the Ala-Ala-Thr backbone sequence) bond onto ice prism planes aligned along a-axes, and inhibit crystal growth on prism planes and on surfaces close to that orientation. The 9.31-A repeat spacing of the AFGP in the polyproline II helix configuration, deduced from NMR studies, matches twice the repeat spacing of ice in the deduced alignment direction, 9.038 A, within 3%. A specific binding model is proposed for the AFGP and for the alpha-helical antifreeze peptide of winter flounder. For AFGP 7-8, two hydroxyl groups of each disaccharide (one disaccharide is attached to each threonine) reside within the ice surface, so that they are shared between the ice crystal and the disaccharide. This provides 24 hydrogen bonds between AFGP 8 and the ice and 30 for AFGP 7, explaining why the chemical adsorption is virtually irreversible and the crystal growth can be stopped virtually completely. The same scheme of sharing polar groups with the ice works well with the alpha-helical antifreeze of winter flounder, for which an amide as well as several hydroxyls are shared. The sharing of polar groups with the ice crystal, rather than hydrogen-bonding to the ice surface, may be a general requirement for adsoprtion-inhibition of freezing. Images FIGURE 2 FIGURE 5 PMID:8431545

  12. Expeditious chemoenzymatic synthesis of CD52 glycopeptide antigens

    PubMed Central

    Huang, Wei; Zhang, Xingyu; Ju, Tongzhong; Cummings, Richard D.; Wang, Lai-Xi

    2013-01-01

    CD52 is a GPI-anchored glycopeptide antigen found on sperm cells and human lymphocytes. Recent structural studies indicate that sperm-associated CD52 antigen carries both a complex type N-glycan and an O-glycan on the polypeptide backbone. To facilitate functional and immunological studies of distinct CD52 glycoforms, we report in this paper the first chemoenzymatic synthesis of homogeneous CD52 glycoforms carrying both N- and O-glycans. The synthetic strategy consists of two key steps: monosaccharide primers GlcNAc and GalNAc were first installed at the pre-determined N- and O-glycosylation sites by a facile solid-phase peptide synthesis, and then the N- and O-glycans were extended by respective enzymatic glycosylations. It was found that the endoglycosidase-catalyzed transglycosylation allowed efficient attachment of an intact N-glycan in a single step at the N-glycosylation site, while the recombinant human T-synthase could independently extend the O-linked GalNAc to form the core 1 O-glycan. This chemoenzymatic approach is highly convergent and permits easy construction of various homogeneous CD52 glycoforms from a common polypeptide precursor. In addition, the introduction of a latent thiol group in the form of protected cysteamine at the C-terminus of the CD52 glycoforms will enable site-specific conjugation to a carrier protein to provide immunogens for generating CD52 glycoform-specific antibodies for functional studies. PMID:20848033

  13. Interaction modes and approaches to glycopeptide and glycoprotein enrichment.

    PubMed

    Chen, Chen-Chun; Su, Wan-Chih; Huang, Bao-Yu; Chen, Yu-Ju; Tai, Hwan-Ching; Obena, Rofeamor P

    2014-02-21

    Protein glycosylation has received increased attention for its critical role in cell biology and diseases. Developing new methodologies to discern phenotype-dependent glycosylation will not only elucidate the mechanistic aspects of cell signaling cascades but also accelerate biomarker discovery for disease diagnosis or prognosis. In the analytical pipeline, enrichment at either the protein or peptide level is the most critical prerequisite for analyzing heterogeneous glycan composition, linkage, site occupancy and carrier proteins. Because the critical factor for choosing a suitable enrichment method is primarily a particular technique's selectivity and affinity towards target glycoproteins/glycopeptides, it is important to fully understand the working principles for the different approaches. For mechanistic insight into the enrichment protocol, we focused on the fundamental chemical and physical processes for the commonly used approaches based on: (a) glycan/peptide physicochemical properties (hydrophilic interactions, chelation/coordination chemistry) and (b) glycan-specific recognition (lectin-based affinity, covalent bond formation by hydrazide/boronic acid). Various interaction modes, such as hydrogen bonding, van der Waals interaction, multivalency, and metal- or water-mediated stabilization, are discussed in detail. In addition, we will review the design of and modifications to such methods, hyphenated approaches, and glycoproteomic applications. Finally, we will outline challenges to existing strategies and offer novel proposals for glycoproteome enrichment. PMID:24336240

  14. Antibiotic-Induced Alterations of the Gut Microbiota Alter Secondary Bile Acid Production and Allow for Clostridium difficile Spore Germination and Outgrowth in the Large Intestine

    PubMed Central

    Bowman, Alison A.; Young, Vincent B.

    2016-01-01

    microbiota, allowing for Clostridium difficile infection, which is a significant public health problem. Changes in the structure of the gut microbiota alter the metabolome, specifically the production of secondary bile acids. Specific bile acids are able to initiate C. difficile spore germination and also inhibit C. difficile growth in vitro, although no study to date has defined physiologically relevant bile acids in the gastrointestinal tract. In this study, we define the bile acids C. difficile spores encounter in the small and large intestines before and after various antibiotic treatments. Antibiotics that alter the gut microbiota and deplete secondary bile acid production allow C. difficile colonization, representing a mechanism of colonization resistance. Multiple secondary bile acids in the large intestine were able to inhibit C. difficile spore germination and growth at physiological concentrations and represent new targets to combat C. difficile in the large intestine. PMID:27239562

  15. Antibiotic-Induced Alterations of the Gut Microbiota Alter Secondary Bile Acid Production and Allow for Clostridium difficile Spore Germination and Outgrowth in the Large Intestine.

    PubMed

    Theriot, Casey M; Bowman, Alison A; Young, Vincent B

    2016-01-01

    , allowing for Clostridium difficile infection, which is a significant public health problem. Changes in the structure of the gut microbiota alter the metabolome, specifically the production of secondary bile acids. Specific bile acids are able to initiate C. difficile spore germination and also inhibit C. difficile growth in vitro, although no study to date has defined physiologically relevant bile acids in the gastrointestinal tract. In this study, we define the bile acids C. difficile spores encounter in the small and large intestines before and after various antibiotic treatments. Antibiotics that alter the gut microbiota and deplete secondary bile acid production allow C. difficile colonization, representing a mechanism of colonization resistance. Multiple secondary bile acids in the large intestine were able to inhibit C. difficile spore germination and growth at physiological concentrations and represent new targets to combat C. difficile in the large intestine. PMID:27239562

  16. Switching antibiotics production on and off in actinomycetes by an IclR family transcriptional regulator from Streptomyces peucetius ATCC 27952.

    PubMed

    Chaudhary, Amit Kumar; Singh, Bijay; Maharjan, Sushila; Jha, Amit Kumar; Kim, Byung-Gee; Sohng, Jae Kyung

    2014-08-01

    Doxorubicin, produced by Streptomyces peucetius ATCC 27952, is tightly regulated by dnrO, dnrN, and dnrI regulators. Genome mining of S. peucetius revealed the presence of the IclR (doxR) type family of transcription regulator mediating the signal-dependent expression of operons at the nonribosomal peptide synthetase gene cluster. Overexpression of doxR in native strain strongly repressed the drug production. Furthermore, it also had a negative effect on the regulatory system of doxorubicin, wherein the transcript of dnrI was reduced to the maximum level in comparision with the other two. Interestingly, the overexpression of the same gene also had strong inhibitory effects on the production of actinorhodin (blue pigment) and undecylprodigiosin (red pigment) in Streptomyces coelicolor M145, herboxidiene production in Streptomyces chromofuscus ATCC 49982, and spinosyn production in Saccharopolyspora spinosa NRRL 18395, respectively. Moreover, DoxR exhibited pleiotropic effects on the production of blue and red pigments in S. coelicolor when grown in different agar media, wherein the production of blue pigment was inhibited in R2YE medium and the red pigment was inhibited in YEME medium. However, the production of both blue and red pigments from S. coelicolor harboring doxR was halted in ISP2 medium, whereas S. coelicolor produced both pigmented antibiotics in the same plate. These consequences demonstrate that the on and off production of these antibiotics was not due to salt stress or media compositions, but was selectively controlled in actinomycetes. PMID:24786531

  17. Mineralization of the antibiotic levofloxacin in aqueous medium by electro-Fenton process: kinetics and intermediate products analysis.

    PubMed

    Yahya, Muna Sh; El Karbane, Miloud; Oturan, Nihal; El Kacemi, Kacem; Oturan, Mehmet A

    2016-05-01

    The present study investigates the feasibility of using electro-Fenton (EF) process for the oxidative degradation of antibiotic levofloxacin (LEV). The EF experiments have been performed in an electrochemical cell using a carbon-felt cathode. The effect of applied current in the range 60-500 mA and catalyst concentration in the range 0.05-0.5 mM on the kinetics of oxidative degradation and mineralization efficiency have been investigated. Degradation of LEV by hydroxyl radicals was found to follow pseudo-first-order reaction kinetics. The absolute rate constant for oxidative degradation of LEV by hydroxyl radical has been determined by a competition kinetics method and found to be (2.48 ± 0.18) × 10(9) M(-1) s(-1). An optimum current value of 400 mA and a catalyst (Fe(2+)) concentration of 0.1 mM were observed to be optimal for an effective degradation of LEV under our operating conditions. Mineralization of aqueous solution of LEV was performed by the chemical oxygen demand analysis and an almost mineralization degree (>91%) was reached at the end of 6 h of electrolysis. A number of intermediate products have been identified using high performance liquid chromatography and liquid chrmatography-mass spectrometry analyses. Based on these identified reaction intermediates, a plausible reaction pathway has been suggested for the mineralization process. The formation and evolution of [Formula: see text] and [Formula: see text] ions released to the medium during the process were also discussed. PMID:26508263

  18. Isolation and molecular characterization of antibiotic-resistant lactic acid bacteria from poultry and swine meat products.

    PubMed

    Aquilanti, Lucia; Garofalo, Cristiana; Osimani, Andrea; Silvestri, Gloria; Vignaroli, Carla; Clementi, Francesca

    2007-03-01

    The transfer via the food chain from animals to humans of microbes that are resistant to antimicrobial agents is of increasing concern. To determine the contributions of nonpathogenic microflora to the occurrence and spread of antibiotic resistance (AR) genes in the food chain, 123 lactic acid bacteria were isolated from 29 samples of raw and processed pork and chicken meat products that had previously tested positive for one or more AR genes that encode clinically relevant ARs: tet(M), tet(O), tet(K), erm(A), erm(B), erm(C), aac (6')-Ie aph (2")-Ia, mecA, and blaZ. All of the isolates were initially tested for their AR gene profiles by PCR. The 59 isolates carrying a tet, erm, or blaZ gene were taken through molecular identification, analyzed by determination of the MIC, and subjected to genetic fingerprinting. Lactococcus garvieae was the predominant species (28 isolates), followed by Lactobacillus plantarum (11 isolates) and L. salivarius (6 isolates), whereas Lactococcus lactis subsp. lactis, Lactobacillus johnsonii, L. reuteri, L. crispatus, and L. brevis were identified at lower frequencies. The tet(M) and erm(B) genes were the most frequently detected. Assessment of multiple resistances in 18 tet positive (tet+) isolates revealed that tet(M) plus erm(B) and tet(K) plus erm(B) were the most frequent AR gene patterns. Partial sequencing of the tet(M) open reading frame of three selected strains showed high sequence similarities (> 99%) with tet(M) genes previously found in human pathogens (Listeria monocytogenes and Neisseria meningitidis). Southern hybridization with plasmid profiles revealed these strains contained tet(M)-carrying plasmids. PMID:17388042

  19. O-glycosylation sites identified from mucin core-1 type glycopeptides from human serum.

    PubMed

    Darula, Zsuzsanna; Sarnyai, Farkas; Medzihradszky, Katalin F

    2016-06-01

    In this work O-linked glycopeptides bearing mucin core-1 type structures were enriched from human serum. Since about 70 % of the O-glycans in human serum bind to the plant lectin Jacalin, we tested a previously successful protocol that combined Jacalin affinity enrichment on the protein- and peptide-level with ERLIC chromatography as a further enrichment step in between, to eliminate the high background of unmodified peptides. In parallel, we developed a simpler and significantly faster new workflow that used two lectins sequentially: wheat germ agglutinin and then Jacalin. The first lectin provides general glycopeptide enrichment, while the second specifically enriches O-linked glycopeptides with Galβ1-3GalNAcα structures. Mass spectrometric analysis of enriched samples showed that the new sample preparation method is more selective and sensitive than the former. Altogether, 52 unique glycosylation sites in 20 proteins were identified in this study. PMID:26729242

  20. Correlation between antibiotic and biocide resistance in mesophilic and psychrotrophic Pseudomonas spp. isolated from slaughterhouse surfaces throughout meat chain production.

    PubMed

    Lavilla Lerma, Leyre; Benomar, Nabil; Casado Muñoz, María del Carmen; Gálvez, Antonio; Abriouel, Hikmate

    2015-10-01

    The aim of this study was to evaluate biocide susceptibility in mesophilic and psychrotrophic pseudomonads isolated from surfaces of a goat and lamb slaughterhouse, which was representative of the region. To determine biocide resistance in pseudomonads, we determined for the first time the epidemiological cut-off values (ECOFFs) of benzalkonium, cetrimide, chlorhexidine, hexachlorophene, P3 oxonia, polyhexamethylene guanidine hydrochloride (PHMG), topax 66 and triclosan being generally very similar in different Pseudomonas spp. with some exceptions. Thus, resistance of pseudomonads was mainly shown to triclosan, and in lesser extent to cetrimide and benzalkonium chloride depending on the species, however they were highly susceptible to industrial formulations of biocides. By means of statistical analysis, positive correlations between antibiotics, biocides and both antimicrobials in pseudomonads were detected suggesting a co- or cross resistance between different antimicrobials in goat and lamb slaughterhouse environment. Cross-resistance between biocides and antibiotics in pseudomonads were especially detected between PHMG or triclosan and different antibiotics depending on the biocide and the population type. Thus, the use of those biocides as disinfectant in slaughterhouse zones must be carefully evaluated because of the selection pressure effect of antimicrobials on the emergence of resistant bacteria which could be spread to the consumer. It is noteworthy that specific industrial formulations such as topax 66 and oxonia P3 showed few correlations with antibiotics (none or 1-2 antibiotics) which should be taken into consideration for disinfection practices in goat and lamb slaughterhouse. PMID:26187825

  1. Evolution of peptidoglycan biosynthesis under the selective pressure of antibiotics in Gram-positive bacteria.

    PubMed

    Mainardi, Jean-Luc; Villet, Régis; Bugg, Timothy D; Mayer, Claudine; Arthur, Michel

    2008-03-01

    Acquisition of resistance to the two classes of antibiotics therapeutically used against Gram-positive bacteria, the glycopeptides and the beta-lactams, has revealed an unexpected flexibility in the peptidoglycan assembly pathway. Glycopeptides select for diversification of the fifth position of stem pentapeptides because replacement of D-Ala by D-lactate or D-Ser at this position prevents binding of the drugs to peptidoglycan precursors. The substitution is generally well tolerated by the classical D,D-transpeptidases belonging to the penicillin-binding protein family, except by low-affinity enzymes. Total elimination of the fifth residue by a D,D-carboxypeptidase requires a novel cross-linking enzyme able to process the resulting tetrapeptide stems. This enzyme, an L,D-transpeptidase, confers cross-resistance to beta-lactams and glycopeptides. Diversification of the side chain of the precursors, presumably in response to the selective pressure of peptidoglycan endopeptidases, is controlled by aminoacyl transferases of the Fem family that redirect specific aminoacyl-tRNAs from translation to peptidoglycan synthesis. Diversification of the side chains has been accompanied by a parallel divergent evolution of the substrate specificity of the L,D-transpeptidases, in contrast to the D,D-transpeptidases, which display an unexpected broad specificity. This review focuses on the role of antibiotics in selecting or counter-selecting diversification of the structure of peptidoglycan precursors and their mode of polymerization. PMID:18266857

  2. Automated glycopeptide analysis--review of current state and future directions.

    PubMed

    Dallas, David C; Martin, William F; Hua, Serenus; German, J Bruce

    2013-05-01

    Glycosylation of proteins is involved in immune defense, cell-cell adhesion, cellular recognition and pathogen binding and is one of the most common and complex post-translational modifications. Science is still struggling to assign detailed mechanisms and functions to this form of conjugation. Even the structural analysis of glycoproteins-glycoproteomics-remains in its infancy due to the scarcity of high-throughput analytical platforms capable of determining glycopeptide composition and structure, especially platforms for complex biological mixtures. Glycopeptide composition and structure can be determined with high mass-accuracy mass spectrometry, particularly when combined with chromatographic separation, but the sheer volume of generated data necessitates computational software for interpretation. This review discusses the current state of glycopeptide assignment software-advances made to date and issues that remain to be addressed. The various software and algorithms developed so far provide important insights into glycoproteomics. However, there is currently no freely available software that can analyze spectral data in batch and unambiguously determine glycopeptide compositions for N- and O-linked glycopeptides from relevant biological sources such as human milk and serum. Few programs are capable of aiding in structural determination of the glycan component. To significantly advance the field of glycoproteomics, analytical software and algorithms are required that: (i) solve for both N- and O-linked glycopeptide compositions, structures and glycosites in biological mixtures; (ii) are high-throughput and process data in batches; (iii) can interpret mass spectral data from a variety of sources and (iv) are open source and freely available. PMID:22843980

  3. Parallel data acquisition of in-source fragmented glycopeptides to sequence the glycosylation sites of proteins.

    PubMed

    Zhao, Jingfu; Song, Ehwang; Zhu, Rui; Mechref, Yehia

    2016-06-01

    Glycosylation plays important roles in maintaining protein stability and controlling biological processes. In recent years, the correlation between aberrant glycoproteins and many diseases has been reported. Hence, qualitative and quantitative analyses of glycoproteins are necessary to understand physiological processes. LC-MS/MS analysis of glycopeptides is faced with the low glycopeptide signal intensities and low peptide sequence identification. In our study, in-source fragmentation (ISF) was used in conjunction with LC-MS/MS to facilitate the parallel acquisition of peptide backbone sequence and glycan composition information. In ISF method, the identification of glycosylation sites depended on the detection of Y1 ion (ion of peptide backbone with an N-acetylglucosamine attached). To attain dominant Y1 ions, a range of source fragmentation voltages was studied using fetuin. A 45 V ISF voltage was found to be the most efficient voltage for the analysis of glycoproteins. ISF was employed to study the glycosylation sites of three model glycoproteins, including fetuin, α1-acid glycoprotein and porcine thyroglobulin. The approach was then used to analyze blood serum samples. Y1 ions of glycopeptides in tryptic digests of samples were detected. Y1 ions of glycopeptides with different sialic acid groups are observed at different retention times, representing the various numbers of sialic acid moieties associated with the same peptide backbone sequence. With ISF facilitating the peptide backbone sequencing of glycopeptides, identified peptide sequence coverage was increased. For example, identified fetuin sequence percentage was improved from 39 to 80% in MASCOT database searching compared to conventional CID method. The formation of Y1 ions and oxonium ions in ISF facilitates glycopeptide sequencing and glycan composition identification. PMID:26957414

  4. Activity of glycopeptides in combination with amikacin or rifampin against Staphylococcus epidermidis biofilms on plastic catheters.

    PubMed

    Pascual, A; Ramirez de Arellano, E; Perea, E J

    1994-06-01

    The in vitro activity of vancomycin and teicoplanin (fourfold the MBC), alone and in combination with amikacin (16 mg/l) or rifampin (1 mg/l), against Staphylococcus epidermidis (slime-producing and non slime-producing strains) biofilms on different plastic catheters was evaluated. The addition of amikacin or rifampin significantly increased the activity of glycopeptides against sessile bacteria. With the slime-producing strain, these combinations were able to sterilize the surface of Vialon and polyvinylchloride catheters. It is concluded that the in vitro activity of glycopeptides against Staphylococcus epidermidis biofilms on plastic catheters can be increased by the addition of amikacin or rifampin. PMID:7957277

  5. First Characterization of a Cluster of VanA-Type Glycopeptide-Resistant Enterococcus faecium, Colombia

    PubMed Central

    Panesso, Diana; Ospina, Sigifredo; Robledo, Jaime; Vela, María Claudia; Peña, Julieta; Hernández, Orville; Reyes, Jinnethe

    2002-01-01

    From August 1998 to October 1999, glycopeptide-resistant enterococci (GRE) were isolated from 23 infected patients at a teaching hospital in Medellín, Colombia. Identification at the species level and by multiplex polymerase chain reaction assay indicated that all isolates were Enterococcus faecium. The isolates were highly resistant to ampicillin, ciprofloxacin, gentamicin, penicillin, streptomycin, teicoplanin, and vancomycin; they were susceptible only to chloramphenicol, linezolid, and nitrofurantoin. Determination of glycopeptide genotype indicated the presence of the vanA gene in all isolates. Molecular typing by pulsed field gel electrophoresis showed that all isolates were closely related. This study is the first molecular characterization of GRE in Colombia. PMID:12194774

  6. Cephamycins, a new family of beta-lactam antibiotics. I. Production by actinomycetes, including Streptomyces lactamdurans sp. n.

    PubMed

    Stapley, E O; Jackson, M; Hernandez, S; Zimmerman, S B; Currie, S A; Mochales, S; Mata, J M; Woodruff, H B; Hendlin, D

    1972-09-01

    A number of actinomycetes isolated from soil were found to produce one or more members of a new family of antibiotics, the cephamycins, which are structurally related to cephalosporin C. The cephamycins were produced in submerged fermentation in a wide variety of media by one or more of eight different species of Streptomyces, including a newly described species, S. lactamdurans. These antibiotics exhibit antibacterial activity against a broad spectrum of bacteria which includes many that are resistant to the cephalosporins and penicillins. PMID:4790552

  7. Safely Coupling Livestock and Crop Production Systems: How Rapidly Do Antibiotic Resistance Genes Dissipate in Soil following a Commercial Application of Swine or Dairy Manure?

    PubMed Central

    Marti, Romain; Tien, Yuan-Ching; Murray, Roger; Scott, Andrew; Sabourin, Lyne

    2014-01-01

    Animal manures recycled onto crop production land carry antibiotic-resistant bacteria. The present study evaluated the fate in soil of selected genes associated with antibiotic resistance or genetic mobility in field plots cropped to vegetables and managed according to normal farming practice. Referenced to unmanured soil, fertilization with swine or dairy manure increased the relative abundance of the gene targets sul1, erm(B), str(B), int1, and IncW repA. Following manure application in the spring of 2012, gene copy number decayed exponentially, reaching background levels by the fall of 2012. In contrast, gene copy number following manure application in the fall of 2012 or spring of 2013 increased significantly in the weeks following application and then declined. In both cases, the relative abundance of gene copy numbers had not returned to background levels by the fall of 2013. Overall, these results suggest that under conditions characteristic of agriculture in a humid continental climate, a 1-year period following a commercial application of raw manure is sufficient to ensure that an additional soil burden of antibiotic resistance genes approaches background. The relative abundance of several gene targets exceeded background during the growing season following a spring application or an application done the previous fall. Results from the present study reinforce the advisability of treating manure prior to use in crop production systems. PMID:24632259

  8. Safely coupling livestock and crop production systems: how rapidly do antibiotic resistance genes dissipate in soil following a commercial application of swine or dairy manure?

    PubMed

    Marti, Romain; Tien, Yuan-Ching; Murray, Roger; Scott, Andrew; Sabourin, Lyne; Topp, Edward

    2014-05-01

    Animal manures recycled onto crop production land carry antibiotic-resistant bacteria. The present study evaluated the fate in soil of selected genes associated with antibiotic resistance or genetic mobility in field plots cropped to vegetables and managed according to normal farming practice. Referenced to unmanured soil, fertilization with swine or dairy manure increased the relative abundance of the gene targets sul1, erm(B), str(B), int1, and IncW repA. Following manure application in the spring of 2012, gene copy number decayed exponentially, reaching background levels by the fall of 2012. In contrast, gene copy number following manure application in the fall of 2012 or spring of 2013 increased significantly in the weeks following application and then declined. In both cases, the relative abundance of gene copy numbers had not returned to background levels by the fall of 2013. Overall, these results suggest that under conditions characteristic of agriculture in a humid continental climate, a 1-year period following a commercial application of raw manure is sufficient to ensure that an additional soil burden of antibiotic resistance genes approaches background. The relative abundance of several gene targets exceeded background during the growing season following a spring application or an application done the previous fall. Results from the present study reinforce the advisability of treating manure prior to use in crop production systems. PMID:24632259

  9. Antibiotic drug discovery.

    PubMed

    Wohlleben, Wolfgang; Mast, Yvonne; Stegmann, Evi; Ziemert, Nadine

    2016-09-01

    Due to the threat posed by the increase of highly resistant pathogenic bacteria, there is an urgent need for new antibiotics; all the more so since in the last 20 years, the approval for new antibacterial agents had decreased. The field of natural product discovery has undergone a tremendous development over the past few years. This has been the consequence of several new and revolutionizing drug discovery and development techniques, which is initiating a 'New Age of Antibiotic Discovery'. In this review, we concentrate on the most significant discovery approaches during the last and present years and comment on the challenges facing the community in the coming years. PMID:27470984

  10. Antibiotic lock therapy: review of technique and logistical challenges

    PubMed Central

    Justo, Julie Ann; Bookstaver, P Brandon

    2014-01-01

    Antibiotic lock therapy (ALT) for the prevention and treatment of catheter-related bloodstream infections is a simple strategy in theory, yet its real-world application may be delayed or avoided due to technical questions and/or logistical challenges. This review focuses on these latter aspects of ALT, including preparation information for a variety of antibiotic lock solutions (ie, aminoglycosides, beta-lactams, fluoroquinolones, folate antagonists, glycopeptides, glycylcyclines, lipopeptides, oxazolidinones, polymyxins, and tetracyclines) and common clinical issues surrounding ALT administration. Detailed data regarding concentrations, additives, stability/compatibility, and dwell times are summarized. Logistical challenges such as lock preparation procedures, use of additives (eg, heparin, citrate, or ethylenediaminetetraacetic acid), timing of initiation and therapy duration, optimal dwell time and catheter accessibility, and risks of ALT are also described. Development of local protocols is recommended in order to avoid these potential barriers and encourage utilization of ALT where appropriate. PMID:25548523

  11. Analysis of recombinant human erythropoietin glycopeptides by capillary electrophoresis electrospray-time of flight-mass spectrometry.

    PubMed

    Giménez, Estela; Ramos-Hernan, Raquel; Benavente, Fernando; Barbosa, José; Sanz-Nebot, Victoria

    2012-01-01

    Capillary electrophoresis electrospray-mass spectrometry was used to detect and characterize the great variety of O- and N-glycopeptide glycoforms of recombinant human erythropoietin (rhEPO) using an orthogonal accelerating time-of-flight mass spectrometer to obtain their exact molecular masses (CE-TOF-MS). rhEPO was digested with trypsin and Glu-C and analyzed by CE-TOF-MS to detect O(126), N(83), N(24)-N(38) and N(24) and N(38) glycopeptide glycoforms, respectively. Neuraminidase was first used to enhance the detection of the glycopeptides and detect all possible glycoforms contained in each glycosylation site. O(126) and N(83) glycopeptides were extensively characterized. Twelve sialoforms corresponding to 5 different glycoforms were detected in N(83), and for the first time, a sulfated sialoform of this glycopeptide was also detected. In the case of O(126), different sialoforms with different types of sialic acids (Neu5Gc and Neu5Ac) were detected and an estimation of the relative percentage of Neu5Gc versus Neu5Ac was also carried out for this glycopeptide. N(24) and N(38) glycosylation sites were also characterized by CE-TOF-MS after Glu-C digestion and these results permitted to rule out some glycan combinations for N(24)-N(38) glycopeptide glycoforms. This study provided a reliable glycopeptide map of rhEPO and may be regarded as an excellent starting point to analyze rhEPO glycopeptides in biological fluids and detect the use of this hormone in sports. PMID:22122935

  12. Affinity Enrichment and Characterization of Mucin Core-1 Type Glycopeptides from Bovine Serum*

    PubMed Central

    Darula, Zsuzsanna; Medzihradszky, Katalin F.

    2009-01-01

    The lack of consensus sequence, common core structure, and universal endoglycosidase for the release of O-linked oligosaccharides makes O-glycosylation more difficult to tackle than N-glycosylation. Structural elucidation by mass spectrometry is usually inconclusive as the CID spectra of most glycopeptides are dominated by carbohydrate-related fragments, preventing peptide identification. In addition, O-linked structures also undergo a gas-phase rearrangement reaction, which eliminates the sugar without leaving a telltale sign at its former attachment site. In the present study we report the enrichment and mass spectrometric analysis of proteins from bovine serum bearing Galβ1–3GalNAcα (mucin core-1 type) structures and the analysis of O-linked glycopeptides utilizing electron transfer dissociation and high resolution, high mass accuracy precursor ion measurements. Electron transfer dissociation (ETD) analysis of intact glycopeptides provided sufficient information for the identification of several glycosylation sites. However, glycopeptides frequently feature precursor ions of low charge density (m/z > ∼850) that will not undergo efficient ETD fragmentation. Exoglycosidase digestion was utilized to reduce the mass of the molecules while retaining their charge. ETD analysis of species modified by a single GalNAc at each site was significantly more successful in the characterization of multiply modified molecules. We report the unambiguous identification of 21 novel glycosylation sites. We also detail the limitations of the enrichment method as well as the ETD analysis. PMID:19674964

  13. Whole Genome Sequencing and Complete Genetic Analysis Reveals Novel Pathways to Glycopeptide Resistance in Staphylococcus aureus

    PubMed Central

    Renzoni, Adriana; Andrey, Diego O.; Jousselin, Ambre; Barras, Christine; Monod, Antoinette; Vaudaux, Pierre; Lew, Daniel; Kelley, William L.

    2011-01-01

    The precise mechanisms leading to the emergence of low-level glycopeptide resistance in Staphylococcus aureus are poorly understood. In this study, we used whole genome deep sequencing to detect differences between two isogenic strains: a parental strain and a stable derivative selected stepwise for survival on 4 µg/ml teicoplanin, but which grows at higher drug concentrations (MIC 8 µg/ml). We uncovered only three single nucleotide changes in the selected strain. Nonsense mutations occurred in stp1, encoding a serine/threonine phosphatase, and in yjbH, encoding a post-transcriptional negative regulator of the redox/thiol stress sensor and global transcriptional regulator, Spx. A missense mutation (G45R) occurred in the histidine kinase sensor of cell wall stress, VraS. Using genetic methods, all single, pairwise combinations, and a fully reconstructed triple mutant were evaluated for their contribution to low-level glycopeptide resistance. We found a synergistic cooperation between dual phospho-signalling systems and a subtle contribution from YjbH, suggesting the activation of oxidative stress defences via Spx. To our knowledge, this is the first genetic demonstration of multiple sensor and stress pathways contributing simultaneously to glycopeptide resistance development. The multifactorial nature of glycopeptide resistance in this strain suggests a complex reprogramming of cell physiology to survive in the face of drug challenge. PMID:21738716

  14. Sugar-Assisted Glycopeptide Ligation with Complex Oligosaccharides: Scope and Limitations

    PubMed Central

    Bennett, Clay S.; Dean, Stephen M.; Payne, Richard J.; Ficht, Simon; Brik, Ashraf

    2008-01-01

    We have previously shown sugar-assisted ligation (SAL) to be a useful method for the convergent construction of glycopeptides. However to date SAL has only been carried out on systems where the thiol auxiliary is attached to a monosaccharide. For SAL to be truly applicable to the construction of fully elaborated glycopeptides and glycoproteins it must be possible to carry out the reaction when the thiol auxiliary is attached to more elaborate sugars, as these are frequently what are observed in nature. Here we examine the effects of glycosylation at C-3, C-4 and C-6 of the C-2 auxiliary-containing glycan. Model glycopeptides where synthesized chemoenzymatically and reacted with peptide thioesters used in our previous work. These studies reveal that SAL is sensitive to extended glycosylation on the auxiliary-containing sugar. While it is possible to carry out SAL with extended glycosylation at C-4 and C-6, the presence of glycosylation at C-3 prevents the ligation from occurring. Additionally, with glycosylation at C-4 the ligation efficiency is affected by the identity of the N-terminal AA, while the nature of the C-terminal residue of the peptide thioester does not appear affect ligation efficiency. These studies provide useful guidelines in deciding when it is appropriate to use SAL in the synthesis of complex glycopeptides and glycoproteins, and how to design ligation junctions for optimal yield. PMID:18698778

  15. Boronic Acid functionalized core-shell polymer nanoparticles prepared by distillation precipitation polymerization for glycopeptide enrichment.

    PubMed

    Qu, Yanyan; Liu, Jianxi; Yang, Kaiguang; Liang, Zhen; Zhang, Lihua; Zhang, Yukui

    2012-07-16

    The boronic acid-functionalized core-shell polymer nanoparticles, poly(N,N-methylenebisacrylamide-co-methacrylic acid)@4-vinylphenylboronic acid (poly(MBA-co-MAA)@VPBA), were successfully synthesized for enriching glycosylated peptides. Such nanoparticles were composed of a hydrophilic polymer core prepared by distillation precipitation polymerization (DPP) and a boronic acid-functionalized shell designed for capturing glycopeptides. Owing to the relatively large amount of residual vinyl groups introduced by DPP on the core surface, the VPBA monomer was coated with high efficiency, working as the shell. Moreover, the overall polymerization route, especially the use of DPP, made the synthesis of nanoparticles facile and time-saving. With the poly(MBA-co-MAA)@VPBA nanoparticles, 18 glycopeptides from horseradish peroxidase (HRP) digest were captured and identified by MALDI-TOF mass spectrometric analysis, relative to eight glycopeptides enriched by using commercially available meta-aminophenylboronic acid agarose under the same conditions. When the concentration of the HRP digest was decreased to as low as 5 nmol, glycopeptides could still be selectively isolated by the prepared nanoparticles. Our results demonstrated that the synthetic poly(MBA-co-MAA)@VPBA nanoparticles might be a promising selective enrichment material for glycoproteome analysis. PMID:22707097

  16. Method development and application to determine potential plant uptake of antibiotics and other drugs in irrigated crop production systems.

    PubMed

    Jones-Lepp, Tammy L; Sanchez, Charles A; Moy, Thomas; Kazemi, Reza

    2010-11-24

    Studies have shown the detection of emerging contaminants (ECs), of which pharmaceuticals are a subset, in surface waters across the United States. The objective of this study was to develop methods, and apply them, to evaluate the potential for food chain transfer when EC-containing waters are used for crop irrigation. Greenhouse experiments were performed in which select food crops were irrigated with water spiked with three antibiotics. Field experiments, at two different sites, were conducted. Select crops were irrigated with wastewater effluent known to contain ECs, EC-free well water, and Colorado River water containing trace-level ECs. The results of the greenhouse studies show the potential for uptake of one or more of the antibiotics evaluated, albeit at very low levels. In those food crops watered with wastewater effluent, only an industrial flavoring agent, N,N'-dimethylphenethylamine (DMPEA), was consistently found. None of the evaluated contaminants were found in crops irrigated with Colorado River water. PMID:20964347

  17. Knowing prior methicillin-resistant Staphylococcus aureus (MRSA) infection or colonization status increases the empirical use of glycopeptides in MRSA bacteraemia and may decrease mortality.

    PubMed

    Robinson, J O; Phillips, M; Christiansen, K J; Pearson, J C; Coombs, G W; Murray, R J

    2014-06-01

    To compare the management and outcome of methicillin-resistant Staphylococcus aureus (MRSA) bacteraemia in patients known to be MRSA-colonized/infected (C-patients) with the management and outcome in those not known to be colonized/infected (NC-patients), we conducted a 10-year retrospective review of MRSA bacteraemia in an adult tertiary hospital. Clinical data were obtained by chart review, and mortality data from linked databases. Prior MRSA colonization/infection status was available to treating clinicians at the time of the bacteraemia as a 'Micro-Alert' tag on the patient's labels, in medical charts, and in electronic information systems. C-patients accounted for 35.4% of all MRSA bacteraemia episodes. C-patients were more likely to be indigenous, to be diabetic, or to have a history of previous S. aureus infection. Markers of illness severity (Simplified Acute Physiology Score (SAPS)-II, need for admission to the intensive-care unit, length of stay, and metastatic seeding) were similar in both groups. Empirical therapy included a glycopeptide in 49.3% of C-patients vs. 18.9% of NC-patients (p <0.01), and contained an antibiotic to which the MRSA isolate tested susceptible in vitro in 56.7% of C-patients vs. 45.1% of NC-patients (p 0.13). All-cause 7-day and 30-day mortality were 7.5% vs. 18.9% (p 0.04), and 22.4% vs. 31.1% (p 0.20), in the C-patient and NC-patient groups, respectively. Knowing MRSA colonization status was significantly associated with lower 30-day mortality in Cox regression analysis (p <0.01). These data suggest that mortality from MRSA bacteraemia is lower in C-patients, which may reflect the earlier use of glycopeptides. The low use of empirical glycopeptides in septic patients known to be previously MRSA-colonized/infected may represent a missed opportunity for infection control to positively impact on clinical management. PMID:24224545

  18. The global role of ppGpp synthesis in morphological differentiation and antibiotic production in Streptomyces coelicolor A3(2)

    PubMed Central

    Hesketh, Andrew; Chen, Wenqiong Joan; Ryding, Jamie; Chang, Sherman; Bibb, Mervyn

    2007-01-01

    Background Regulation of production of the translational apparatus via the stringent factor ppGpp in response to amino acid starvation is conserved in many bacteria. However, in addition to this core function, it is clear that ppGpp also exhibits genus-specific regulatory effects. In this study we used Affymetrix GeneChips to more fully characterize the regulatory influence of ppGpp synthesis on the biology of Streptomyces coelicolor A3(2), with emphasis on the control of antibiotic biosynthesis and morphological differentiation. Results Induction of ppGpp synthesis repressed transcription of the major sigma factor hrdB, genes with functions associated with active growth, and six of the thirteen conservons present in the S. coelicolor genome. Genes induced following ppGpp synthesis included the alternative sigma factor SCO4005, many for production of the antibiotics CDA and actinorhodin, the regulatory genes SCO4198 and SCO4336, and two alternative ribosomal proteins. Induction of the CDA and actinorhodin clusters was accompanied by an increase in transcription of the pathway regulators cdaR and actII-ORF4, respectively. Comparison of transcriptome profiles of a relA null strain, M570, incapable of ppGpp synthesis with its parent M600 suggested the occurrence of metabolic stress in the mutant. The failure of M570 to sporulate was associated with a stalling between production of the surfactant peptide SapB, and of the hydrophobins: it overproduced SapB but failed to express the chaplin and rodlin genes. Conclusion In S. coelicolor, ppGpp synthesis influences the expression of several genomic elements that are particularly characteristic of streptomycete biology, notably antibiotic gene clusters, conservons, and morphogenetic proteins. PMID:17683547

  19. Characterization of intact N- and O-linked glycopeptides using higher energy collisional dissociation

    SciTech Connect

    Cao, Li; Tolic, Nikola; Qu, Yi; Meng, Da; Zhao, Rui; Zhang, Qibin; Moore, Ronald J.; Zink, Erika M.; Lipton, Mary S.; Pasa-Tolic, Ljiljana; Wu, Si

    2014-01-15

    Simultaneous elucidation of the glycan structure and the glycosylation site are needed to reveal the biological function of protein glycosylation. In this study, we employed a recent type of fragmentation termed higher energy collisional dissociation (HCD) to examine fragmentation patterns of intact glycopeptides generated from a mixture of standard glycosylated proteins. The normalized collisional energy (NCE) value for HCD was varied from 30% to 60% to evaluate the optimal conditions for the fragmentation of peptide backbones and glycoconjugates. Our results indicated that HCD with lower NCE valuespreferentially fragmented the sugar chains attached to the peptides to generate a ladder of neutral loss of monosaccharides, thus enabling the putative glycan structure characterization. Also, detection of the oxonium ions enabled unambiguous differentiation of glycopeptides from non-glycopeptides. On the contrary, HCD with higher NCE values preferentially fragmented the peptide backbone and thus provided information needed for confident peptide identification. We evaluated the HCD approach with alternating NCE parameters for confident characterization of intact N-linked and O-linked glycopeptides in a single liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. In addition, we applied a novel data analysis pipeline, so-called GlycoFinder, to form a basis for automated data analysis. Overall, 38 unique intact glycopeptides corresponding to eight glycosylation sites (including six N-linked and two O-linked sites) were confidently identified from a standard protein mixture. This approach provided concurrent characterization of both, the peptide and the glycan, thus enabling comprehensive structural characterization of glycoproteins in a single LC-MS/MS analysis.

  20. Cell surface glycopeptides from human intestinal epithelial cell lines derived from normal colon and colon adenocarcinomas

    SciTech Connect

    Youakim, A.; Herscovics, A.

    1985-11-01

    The cell surface glycopeptides from an epithelial cell line (CCL 239) derived from normal human colon were compared with those from three cell lines (HCT-8R, HCT-15, and CaCo-2) derived independently from human colonic adenocarcinomas. Cells were incubated with D-(2-TH)mannose or L-(5,6-TH)fucose for 24 h and treated with trypsin to release cell surface components which were then digested exhaustively with Pronase and fractionated on Bio-Gel P-6 before and after treatment with endo-beta-N-acetylglucosaminidase H. The most noticeable difference between the labeled glycopeptides from the tumor and CCL 239 cells was the presence in the former of an endo-beta-N-acetylglucosaminidase H-resistant high molecular weight glycopeptide fraction which was eluted in the void volume of Bio-Gel P-6. This fraction was obtained with both labeled mannose and fucose as precursors. However, acid hydrolysis of this fraction obtained after incubation with (2-TH)mannose revealed that as much as 60-90% of the radioactivity was recovered as fucose. Analysis of the total glycopeptides (cell surface and cell pellet) obtained after incubation with (2-TH)mannose showed that from 40-45% of the radioactivity in the tumor cells and less than 10% of the radioactivity in the CCL 239 cells was recovered as fucose. After incubation of the HCT-8R cells with D-(1,6-TH)glucosamine and L-(1- UC)fucose, strong acid hydrolysis of the labeled glycopeptide fraction excluded from Bio-Gel P-6 produced TH-labeled N-acetylglucosamine and N-acetylgalactosamine.

  1. Glycoproteomic analysis of embryonic stem cells: identification of potential glycobiomarkers using lectin affinity chromatography of glycopeptides

    PubMed Central

    Alvarez-Manilla, Gerardo; Warren, Nicole L.; Atwood, James; Orlando, Ron; Dalton, Stephen; Pierce, Michael

    2011-01-01

    Numerous studies have recently focused on the identification of specific glycan biomarkers; given the important roles that protein linked glycans play, for example, during development and disease progression. The identification of protein glycobiomarkers, which are part of a very complex proteome, has involved the use of fractionation techniques such as lectin affinity chromatography. In this study, the glycoproteomic characterization of pluripotent murine embryonic stem cells (ES) and from ES cells that were differentiated into embroid bodies (EB) was performed using immobilized Concanavalin A (ConA). This procedure allowed the isolation of glycopeptides that express biantennary and hybrid N-linked structures (ConA2 fraction) as well as high mannose glycans (ConA3 fraction), that were abundant in both ES and EB stages. A total of 293 unique N-linked glycopeptide sequences (from 180 glycoproteins) were identified in the combined data sets from ES and EB cells. Of these glycopeptides, a total of 119 sequences were identified exclusively in only one of the lectin bound fractions, (24 in the ES-ConA2, 15 in the ES-ConA3, 16 in the EB-ConA2 and 64 in the EB-ConA3). Results from this study allowed the identification of individual N-glycosylation sites of proteins that express specific glycan types. The absence of some of these lectin bound glycopeptides in a cell stage suggested that they were derived from proteins that were either expressed exclusively on a defined developmental stage, or were expressed in both cell stages but carried the lectin bound oligosaccharides in only one of them. Therefore, these lectin bound glycopeptides can be considered as stage specific glycobiomarkers. PMID:19545112

  2. Presence of exoY, exoS, exoU and exoT genes, antibiotic resistance and biofilm production among Pseudomonas aeruginosa isolates in Northwest Iran

    PubMed Central

    Azimi, Somayeh; Kafil, Hossein Samadi; Baghi, Hossein Bannazadeh; Shokrian, Saeed; Najaf, Khadijeh; Asgharzadeh, Mohammad; Yousefi, Mehdi; Shahrivar, Firooz; Aghazadeh, Mohammad

    2016-01-01

    Background: Pseudomonas aeruginosa, as Gram-negative rod bacilli, has an important role in human infection. In the present study we aimed to investigate the presence of exo genes and biofilm production among Pseudomonas aeruginosa isolates in Northwest Iran. Material and methods: 160 isolates of P. aeruginosa were collected and identified by biochemical tests and were characterized for antibiotic resistance. Biofilm production was evaluated by microtiter plate assay and the presence of exo genes was evaluated by allele-specific PCR (polymerase chain reaction). Chi-square test was used for statistical analysis. Results: The most effective antibiotics against isolates were colistin and polymyxin B. 87% of the isolates were biofilm producers of which 69% were strongly biofilm producers. 55% of the isolates carried exoY, 52% of the isolates carried exoU, and 26.3% and 5% carried exoS and exoT, respectively. Conclusion: Our findings showed different distribution of exo genes in clinical isolates of P. aeruginosa in Northwest Iran. ExoS and exoU were more prevalent in non-biofilm producers and exoY was more prevalent in biofilm producer isolates. These results might indicate the importance of exoY in biofilm production of Pseudomonas aeruginosa. PMID:26958458

  3. Resistance to Antibiotics Mediated by Target Alterations

    NASA Astrophysics Data System (ADS)

    Spratt, Brian G.

    1994-04-01

    The development of resistance to antibiotics by reductions in the affinities of their enzymatic targets occurs most rapidly for antibiotics that inactivate a single target and that are not analogs of substrate. In these cases of resistance (for example, resistance to rifampicin), numerous single amino acid substitutions may provide large decreases in the affinity of the target for the antibiotic, leading to clinically significant levels of resistance. Resistance due to target alterations should occur much more slowly for those antibiotics (penicillin, for example) that inactivate multiple targets irreversibly by acting as close analogs of substrate. Resistance to penicillin because of target changes has emerged, by unexpected mechanisms, only in a limited number of species. However, inactivating enzymes commonly provide resistance to antibiotics that, like penicillin, are derived from natural products, although such enzymes have not been found for synthetic antibiotics. Thus, the ideal antibiotic would be produced by rational design, rather than by the modification of a natural product.

  4. Generic antibiotics in Japan.

    PubMed

    Fujimura, Shigeru; Watanabe, Akira

    2012-08-01

    Generic drugs have been used extensively in many developed countries, although their use in Japan has been limited. Generic drugs reduce drug expenses and thereby national medical expenditure. Because generic drugs provide advantages for both public administration and consumers, it is expected that they will be more widely used in the future. However, the diffusion rate of generic drugs in Japan is quite low compared with that of other developed countries. An investigation on generic drugs conducted by the Ministry of Health, Labour and Welfare in Japan revealed that 17.2 % of doctors and 37.2 % of patients had not used generic drugs. The major reasons for this low use rate included distrust of off-patent products and lower drug price margin compared with the brand name drug. The generic drugs available in the market include external drugs such as wet packs, antihypertensive agents, analgesics, anticancer drugs, and antibiotics. Among them, antibiotics are frequently used in cases of acute infectious diseases. When the treatment of these infections is delayed, the infection might be aggravated rapidly. The pharmacokinetics-pharmacodynamics (PK-PD) theory has been adopted in recent chemotherapy, and in many cases, the most appropriate dosage and administration of antibiotics are determined for individual patients considering renal function; high-dosage antibiotics are used preferably for a short duration. Therefore, a highly detailed antimicrobial agent is necessary. However, some of the generic antibiotics have less antibacterial potency or solubility than the brand name products. We showed that the potency of the generic products of vancomycin and teicoplanin is lower than that of the branded drugs by 14.6 % and 17.3 %, respectively. Furthermore, we confirmed that a generic meropenem drug for injection required about 82 s to solubilize in saline, whereas the brand product required only about 21 s. It was thought that the cause may be the difference in size of bulk

  5. [Interrelation of the antibiotic sensitivity (resistance) of staphylococci, clinical forms of the infection and production of protein A].

    PubMed

    Fomenko, G A

    1984-06-01

    Two hundred and thirty-two strains of Staph. aureus isolated from patients with staphylococcal infections were studied. The strains were isolated from the blood of patients with sepsis, from the purulent foci on the skin and in the subcutaneous fat, from the nasopharyngeal mucosa of patients with tonsillitis and inflammation of the upper respiratory tract, from the sputum of patients with the pneumonia signs and from the pus of patients with otitis. The pathogens were identified with the routine methods. The quantitative content of protein A in the strains was determined by the method of indirect hemagglutination with red blood cells sensitized with the hemolytic serum. The data obtained were analysed with regard to the strain group and characteristics of the strain resistance or sensitivity to benzylpenicillin, erythromycin, oleandomycin, chloramphenicol, streptomycin, neomycin, kanamycin, monomycin, ristomycin and furagin K. Statistically significant differences in the protein A content in certain strain groups were observed. These differences might be correlated with the strain antibiotic resistance but not sensitivity. Pronounced changes in the levels of protein A were detected in the staphylococcal hemocultures resistant to erythromycin and streptomycin. The cultures resistant to erythromycin were characterized by decreased content of protein A and those resistant to streptomycin were characterized by increased content of protein A. Comparison of the antibiotic sensitivity of the strains of 5 groups by variation statistics revealed significant differences in the levels of sensitivity to streptomycin, neomycin, kanamycin, monomycin, ristomycin and furagin K but not to erythromycin, oleandomycin and chloramphenicol in the strains of certain groups. The staphylococcal hemocultures isolated from patients with sepsis proved to be the most sensitive to the antibiotics. PMID:6476803

  6. Antibiotic resistance in wild birds

    PubMed Central

    Bonnedahl, Jonas

    2014-01-01

    Wild birds have been postulated as sentinels, reservoirs, and potential spreaders of antibiotic resistance. Antibiotic-resistant bacteria have been isolated from a multitude of wild bird species. Several studies strongly indicate transmission of resistant bacteria from human rest products to wild birds. There is evidence suggesting that wild birds can spread resistant bacteria through migration and that resistant bacteria can be transmitted from birds to humans and vice versa. Through further studies of the spatial and temporal distribution of resistant bacteria in wild birds, we can better assess their role and thereby help to mitigate the increasing global problem of antibiotic resistance. PMID:24697355

  7. Exploring Site-Specific N-Glycosylation Microheterogeneity of Haptoglobin using Glycopeptide CID Tandem Mass Spectra and Glycan Database Search

    PubMed Central

    Chandler, Kevin Brown; Pompach, Petr; Goldman, Radoslav

    2013-01-01

    Glycosylation is a common protein modification with a significant role in many vital cellular processes and human diseases, making the characterization of protein-attached glycan structures important for understanding cell biology and disease processes. Direct analysis of protein N-glycosylation by tandem mass spectrometry of glycopeptides promises site-specific elucidation of N-glycan microheterogeneity, something which detached N-glycan and de-glycosylated peptide analyses cannot provide. However, successful implementation of direct N-glycopeptide analysis by tandem mass spectrometry remains a challenge. In this work, we consider algorithmic techniques for the analysis of LC-MS/MS data acquired from glycopeptide-enriched fractions of enzymatic digests of purified proteins. We implement a computational strategy which takes advantage of the properties of CID fragmentation spectra of N-glycopeptides, matching the MS/MS spectra to peptide-glycan pairs from protein sequences and glycan structure databases. Significantly, we also propose a novel false-discovery-rate estimation technique to estimate and manage the number of false identifications. We use a human glycoprotein standard, haptoglobin, digested with trypsin and GluC, enriched for glycopeptides using HILIC chromatography, and analyzed by LC-MS/MS to demonstrate our algorithmic strategy and evaluate its performance. Our software, GlycoPeptideSearch (GPS), assigned glycopeptide identifications to 246 of the spectra at false-discovery-rate 5.58%, identifying 42 distinct haptoglobin peptide-glycan pairs at each of the four haptoglobin N-linked glycosylation sites. We further demonstrate the effectiveness of this approach by analyzing plasma-derived haptoglobin, identifying 136 N-linked glycopeptide spectra at false-discovery-rate 0.4%, representing 15 distinct glycopeptides on at least three of the four N-linked glycosylation sites. The software, GlycoPeptideSearch, is available for download from http

  8. N-Linked Glycosyl Auxiliary-Mediated Native Chemical Ligation on Aspartic Acid: Application towards N-Glycopeptide Synthesis.

    PubMed

    Chai, Hua; Le Mai Hoang, Kim; Vu, Minh Duy; Pasunooti, Kalyan; Liu, Chuan-Fa; Liu, Xue-Wei

    2016-08-22

    A practical approach towards N-glycopeptide synthesis using an auxiliary-mediated dual native chemical ligation (NCL) has been developed. The first NCL connects an N-linked glycosyl auxiliary to the thioester side chain of an N-terminal aspartate oligopeptide. This intermediate undergoes a second NCL with a C-terminal thioester oligopeptide. Mild cleavage provides the desired N-glycopeptide. PMID:27444333

  9. Exploring site-specific N-glycosylation microheterogeneity of haptoglobin using glycopeptide CID tandem mass spectra and glycan database search.

    PubMed

    Chandler, Kevin Brown; Pompach, Petr; Goldman, Radoslav; Edwards, Nathan

    2013-08-01

    Glycosylation is a common protein modification with a significant role in many vital cellular processes and human diseases, making the characterization of protein-attached glycan structures important for understanding cell biology and disease processes. Direct analysis of protein N-glycosylation by tandem mass spectrometry of glycopeptides promises site-specific elucidation of N-glycan microheterogeneity, something that detached N-glycan and deglycosylated peptide analyses cannot provide. However, successful implementation of direct N-glycopeptide analysis by tandem mass spectrometry remains a challenge. In this work, we consider algorithmic techniques for the analysis of LC-MS/MS data acquired from glycopeptide-enriched fractions of enzymatic digests of purified proteins. We implement a computational strategy that takes advantage of the properties of CID fragmentation spectra of N-glycopeptides, matching the MS/MS spectra to peptide-glycan pairs from protein sequences and glycan structure databases. Significantly, we also propose a novel false discovery rate estimation technique to estimate and manage the number of false identifications. We use a human glycoprotein standard, haptoglobin, digested with trypsin and GluC, enriched for glycopeptides using HILIC chromatography, and analyzed by LC-MS/MS to demonstrate our algorithmic strategy and evaluate its performance. Our software, GlycoPeptideSearch (GPS), assigned glycopeptide identifications to 246 of the spectra at a false discovery rate of 5.58%, identifying 42 distinct haptoglobin peptide-glycan pairs at each of the four haptoglobin N-linked glycosylation sites. We further demonstrate the effectiveness of this approach by analyzing plasma-derived haptoglobin, identifying 136 N-linked glycopeptide spectra at a false discovery rate of 0.4%, representing 15 distinct glycopeptides on at least three of the four N-linked glycosylation sites. The software, GlycoPeptideSearch, is available for download from http

  10. Facts about Antibiotic Resistance

    MedlinePlus

    ... Trends and Cost Español: Datos breves Facts about Antibiotic Resistance Antibiotic resistance has been called one of the world’s most ... antibiotic use is a key strategy to control antibiotic resistance. Antibiotic resistance in children is of particular concern ...

  11. Synthetic, Structural and Biosynthetic Studies of an Unusual Phospho-Glycopeptide Derived from α-Dystroglycan

    PubMed Central

    Mo, Kai-For; Fang, Tao; Stalnaker, Stephanie H.; Kirby, Pamela S.; Liu, Mian; Wells, Lance; Pierce, Michael; Live, David H.; Boons, Geert-Jan

    2011-01-01

    Aberrant glycosylation of α-dystroglycan (α-DG) results in loss of interactions with the extracellular matrix and is central to the pathogenesis of several disorders. To examine protein glycosylation of α-DG, a facile synthetic approach has been developed for the preparation of unusual phosphorylated O-mannosyl glycopeptides derived from α-DG by a strategy in which properly protected phospho-mannosides are coupled with a Fmoc protected threonine derivative, followed by the use of the resulting derivatives in automated solid phase glycopeptide synthesis using hyper-acid sensitive Sieber amide resin. Synthetic efforts also provided a reduced phospho-trisaccharide and the NMR data of this derivative confirmed the proper structural assignment of the unusual phospho-glycan structure. The glycopeptides made it possible to explore factors that regulate the elaboration of critical glycans. It was established that a glycopeptide having a 6-phospho-O-mannosyl residue is not an acceptor for action by the enzyme POMGnT1, which attaches β(1,2)-GlcNAc to O-mannosyl moietes, whereas the unphosphorylated derivate was readily extended by the enzyme. This finding implies a specific sequence of events in determining the structural fate of the O-glycan. It has also been found that the activity of POMGnT1 is dependent on the location of the acceptor site in the context of the underlying polypeptide/glycopeptide sequence. Conformational analysis by NMR has shown that the O-mannosyl modification does not exert major conformational effect on the peptide backbone. It is, however, proposed that these residues, introduced at the early stages of glycoprotein glycosylation, have an ability to regulate the loci of subsequent O-GalNAc additions, which do exert conformational effects. The studies show that through access to discrete glycopeptide structures, it is possible to reveal complex regulation of O-glycan processing on α-DG that has significant implications both for its normal post

  12. Glycopeptide Site Heterogeneity and Structural Diversity Determined by Combined Lectin Affinity Chromatography/IMS/CID/MS Techniques

    NASA Astrophysics Data System (ADS)

    Zhu, Feifei; Trinidad, Jonathan C.; Clemmer, David E.

    2015-07-01

    Glycopeptides from a tryptic digest of chicken ovomucoid were enriched using a simplified lectin affinity chromatography (LAC) platform, and characterized by high-resolution mass spectrometry (MS) as well as ion mobility spectrometry (IMS)-MS. The LAC platform effectively enriched the glycoproteome, from which a total of 117 glycopeptides containing 27 glycan forms were identified for this protein. IMS-MS analysis revealed a high degree of glycopeptide site heterogeneity. Comparison of the IMS distributions of the glycopeptides from different charge states reveals that higher charge states allow more structures to be resolved. Presumably the repulsive interactions between charged sites lead to more open configurations, which are more readily separated compared with the more compact, lower charge state forms of the same groups of species. Combining IMS with collision induced dissociation (CID) made it possible to determine the presence of isomeric glycans and to reconstruct their IMS profiles. This study illustrates a workflow involving hybrid techniques for determining glycopeptide site heterogeneity and evaluating structural diversity of glycans and glycopeptides.

  13. Synthesis of Zwitterionic Polymer Particles via Combined Distillation Precipitation Polymerization and Click Chemistry for Highly Efficient Enrichment of Glycopeptide.

    PubMed

    Liu, Jianxi; Yang, Kaiguang; Shao, Wenya; Li, Senwu; Wu, Qi; Zhang, Shen; Qu, Yanyan; Zhang, Lihua; Zhang, Yukui

    2016-08-31

    Because of the low abundance of glycopeptide in natural biological samples, methods for efficient and selective enrichment of glycopeptides play a significant role in mass spectrometry (MS)-based glycoproteomics. In this study, a novel kind of zwitterionic hydrophilic interaction chromatography polymer particles, namely, poly(N,N-methylenebisacrylamide-co-methacrylic acid)@l-Cys (poly(MBAAm-co-MAA)@l-Cys), for the enrichment of glycopeptides was synthesized by a facile and efficient approach that combined distillation precipitation polymerization (DPP) and "thiol-ene" click reaction. In the DPP approach, residual vinyl groups explored outside the core with high density, then the functional ligand cysteine was immobilized onto the surface of core particles by highly efficient thiol-ene click reaction. Taking advantage of the unique structure of poly(MBAAm-co-MAA)@l-Cys, the resulting particles possess remarkable enrichment selectivity for glycopeptides from the tryptic digested human immunoglobulin G. The polymer particles were successfully employed for the analysis of human plasma, and 208 unique glycopeptides corresponding to 121 glycoproteins were reliably identified in triple independent nano-LC-MS/MS runs. The selectivity toward glycopeptides of these particles poly(MBAAm-co-MAA)@l-Cys is ∼2 times than that of the commercial beads. These results demonstrated that these particles had great potential for large-scale glycoproteomics research. Moreover, the strategy with the combination of DPP and thiol-ene click chemistry might be a facile method to produce functional polymer particles for bioenrichment application. PMID:27498760

  14. Glycopeptide Site Heterogeneity and Structural Diversity Determined by Combined Lectin Affinity Chromatography/IMS/CID/MS Techniques.

    PubMed

    Zhu, Feifei; Trinidad, Jonathan C; Clemmer, David E

    2015-07-01

    Glycopeptides from a tryptic digest of chicken ovomucoid were enriched using a simplified lectin affinity chromatography (LAC) platform, and characterized by high-resolution mass spectrometry (MS) as well as ion mobility spectrometry (IMS)-MS. The LAC platform effectively enriched the glycoproteome, from which a total of 117 glycopeptides containing 27 glycan forms were identified for this protein. IMS-MS analysis revealed a high degree of glycopeptide site heterogeneity. Comparison of the IMS distributions of the glycopeptides from different charge states reveals that higher charge states allow more structures to be resolved. Presumably the repulsive interactions between charged sites lead to more open configurations, which are more readily separated compared with the more compact, lower charge state forms of the same groups of species. Combining IMS with collision induced dissociation (CID) made it possible to determine the presence of isomeric glycans and to reconstruct their IMS profiles. This study illustrates a workflow involving hybrid techniques for determining glycopeptide site heterogeneity and evaluating structural diversity of glycans and glycopeptides. PMID:25840811

  15. The rpoZ Gene, Encoding the RNA Polymerase Omega Subunit, Is Required for Antibiotic Production and Morphological Differentiation in Streptomyces kasugaensis

    PubMed Central

    Kojima, Ikuo; Kasuga, Kano; Kobayashi, Masayuki; Fukasawa, Akira; Mizuno, Satoshi; Arisawa, Akira; Akagawa, Hisayoshi

    2002-01-01

    The occurrence of pleiotropic mutants that are defective in both antibiotic production and aerial mycelium formation is peculiar to streptomycetes. Pleiotropic mutant KSB was isolated from wild-type Streptomyces kasugaensis A1R6, which produces kasugamycin, an antifungal aminoglycoside antibiotic. A 9.3-kb DNA fragment was cloned from the chromosomal DNA of strain A1R6 by complementary restoration of kasugamycin production and aerial hypha formation to mutant KSB. Complementation experiments with deletion plasmids and subsequent DNA analysis indicated that orf5, encoding 90 amino acids, was responsible for the restoration. A protein homology search revealed that orf5 was a homolog of rpoZ, the gene that is known to encode RNA polymerase subunit omega (ω), thus leading to the conclusion that orf5 was rpoZ in S. kasugaensis. The pleiotropy of mutant KSB was attributed to a 2-bp frameshift deletion in the rpoZ region of mutant KSB, which probably resulted in a truncated, incomplete ω of 47 amino acids. Furthermore, rpoZ-disrupted mutant R6D4 obtained from strain A1R6 by insertion of Tn5 aphII into the middle of the rpoZ-coding region produced neither kasugamycin nor aerial mycelia, similar to mutant KSB. When rpoZ of S. kasugaensis and Streptomyces coelicolor, whose deduced products differed in the sixth amino acid residue, were introduced into mutant R6D4 via a plasmid, both transformants produced kasugamycin and aerial hyphae without significant differences. This study established that rpoZ is required for kasugamycin production and aerial mycelium formation in S. kasugaensis and responsible for pleiotropy. PMID:12426327

  16. 21 CFR 333.110 - First aid antibiotic active ingredients.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 5 2010-04-01 2010-04-01 false First aid antibiotic active ingredients. 333.110... (CONTINUED) DRUGS FOR HUMAN USE TOPICAL ANTIMICROBIAL DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE First Aid Antibiotic Drug Products § 333.110 First aid antibiotic active ingredients. The product consists of any...

  17. 21 CFR 333.110 - First aid antibiotic active ingredients.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 5 2011-04-01 2011-04-01 false First aid antibiotic active ingredients. 333.110... (CONTINUED) DRUGS FOR HUMAN USE TOPICAL ANTIMICROBIAL DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE First Aid Antibiotic Drug Products § 333.110 First aid antibiotic active ingredients. The product consists of any...

  18. 21 CFR 333.110 - First aid antibiotic active ingredients.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 5 2013-04-01 2013-04-01 false First aid antibiotic active ingredients. 333.110... (CONTINUED) DRUGS FOR HUMAN USE TOPICAL ANTIMICROBIAL DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE First Aid Antibiotic Drug Products § 333.110 First aid antibiotic active ingredients. The product consists of any...

  19. 21 CFR 333.110 - First aid antibiotic active ingredients.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 5 2012-04-01 2012-04-01 false First aid antibiotic active ingredients. 333.110... (CONTINUED) DRUGS FOR HUMAN USE TOPICAL ANTIMICROBIAL DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE First Aid Antibiotic Drug Products § 333.110 First aid antibiotic active ingredients. The product consists of any...

  20. 9 CFR 114.10 - Antibiotics as preservatives.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Antibiotics as preservatives. 114.10... BIOLOGICAL PRODUCTS § 114.10 Antibiotics as preservatives. Antibiotics are authorized for use as preservatives for biological products if used within the limitations as to kinds and amounts prescribed in...

  1. 9 CFR 114.10 - Antibiotics as preservatives.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Antibiotics as preservatives. 114.10... BIOLOGICAL PRODUCTS § 114.10 Antibiotics as preservatives. Antibiotics are authorized for use as preservatives for biological products if used within the limitations as to kinds and amounts prescribed in...

  2. 9 CFR 114.10 - Antibiotics as preservatives.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Antibiotics as preservatives. 114.10... BIOLOGICAL PRODUCTS § 114.10 Antibiotics as preservatives. Antibiotics are authorized for use as preservatives for biological products if used within the limitations as to kinds and amounts prescribed in...

  3. 9 CFR 114.10 - Antibiotics as preservatives.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Antibiotics as preservatives. 114.10... BIOLOGICAL PRODUCTS § 114.10 Antibiotics as preservatives. Antibiotics are authorized for use as preservatives for biological products if used within the limitations as to kinds and amounts prescribed in...

  4. 9 CFR 114.10 - Antibiotics as preservatives.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Antibiotics as preservatives. 114.10... BIOLOGICAL PRODUCTS § 114.10 Antibiotics as preservatives. Antibiotics are authorized for use as preservatives for biological products if used within the limitations as to kinds and amounts prescribed in...

  5. cmdABCDEF, a cluster of genes encoding membrane proteins for differentiation and antibiotic production in Streptomyces coelicolor A3(2)

    PubMed Central

    2009-01-01

    Background Streptomyces coelicolor is the most studied Streptomyces species and an excellent model for studying differentiation and antibiotic production. To date, many genes have been identified to be required for its differentiation (e.g. bld genes for aerial growth and whi genes for sporulation) and antibiotics production (including actII-orf4, redD, cdaR as pathway-specific regulatory genes and afsR, absA1/A2 as pleiotropic regulatory genes). Results A gene cluster containing six genes (SCO4126-4131) was proved to be co-transcribed in S. coelicolor. Deletions of cmdABCDEF (SCO4126-4131) displayed defective sporulation including formation of aberrant branches, and abnormalities in chromosome segregation and spore septation. Disruption mutants of apparently orthologous genes of S. lividans and S. avermitilis also showed defective sporulation, implying that the role of these genes is similar among Streptomyces. Transcription of cmdB, and therefore presumably of the whole operon, was regulated developmentally. Five of the encoded proteins (CmdA, C, D, E, F) were predicted membrane proteins. The other, CmdB, a predicted ATP/GTP-binding protein with an ABC-transporter-ATPase domain shown here to be essential for its function, was also located on the cell membrane. These results indicate that CmdABCDEF proteins mainly affect Streptomyces differentiation at an early stage of aerial hyphae formation, and suggest that these proteins may form a complex on cell membrane for proper segregation of chromosomes. In addition, deletions of cmdABCDEF also revealed over-production of blue-pigmented actinorhodin (Act) via activation of transcription of the pathway-specific regulatory gene actII-orf4 of actinorhodin biosynthesis. Conclusion In this study, six co-transcribed genes cmdABCDEF were identified by their effects on differentiation and antibiotic production in Streptomyces coelicolor A3(2). These six membrane-located proteins are possibly assembled into a complex to

  6. Glycopeptide Nanoconjugates Based on Multilayer Self-Assembly as an Antitumor Vaccine.

    PubMed

    Liu, Yan-Fang; Sun, Zhan-Yi; Chen, Pu-Guang; Huang, Zhi-Hua; Gao, Yue; Shi, Lei; Zhao, Yu-Fen; Chen, Yong-Xiang; Li, Yan-Mei

    2015-08-19

    Antitumor vaccine, which is promising for tumor therapy, has been extensively studied. Some encouraging results of chemically synthetic vaccine designs based on the tumor-associated antigen mucin 1 have been achieved. However, some shortcomings such as low efficiency and difficult purification restrict their clinical application. To overcome these difficulties, we designed a novel antitumor vaccine of glycopeptide nanoconjugates based on the multilayer self-assembly through the interaction of positive and negative charges. This vaccine formed the spherical structure and effectively activated the macrophage in vitro. Besides, it also induced high titer of antibodies against mucin 1 glycopeptide. The induced antibodies could highly bind to the tumor cells and effectively kill them by activation of the complement dependent cytotoxicity complex. This novel strategy provides a new way for the development of simple and effective antitumor vaccine. PMID:26108637

  7. Software for Automated Interpretation of Mass Spectrometry Data from Glycans and Glycopeptides

    PubMed Central

    Woodin, Carrie L.; Maxon, Morgan; Desaire, Heather

    2013-01-01

    The purpose of this review is to provide those interested in glycosylation analysis with the most updated information on the availability of automated tools for MS characterization of N-linked and O-linked glycosylation types. Specifically, this review describes software tools that facilitate elucidation of glycosylation from MS data on the basis of mass alone, as well as software designed to speed the interpretation of glycan and glycopeptide fragmentation from MS/MS data. This review focuses equally on software designed to interpret the composition of released glycans and on tools to characterize N-linked and O-linked glycopeptides. Several websites have been compiled and described that will be helpful to the reader who is interested in further exploring the described tools. PMID:23293784

  8. Antibiotic resistance, virulence determinants and production of biogenic amines among enterococci from ovine, feline, canine, porcine and human milk

    PubMed Central

    2013-01-01

    Background Recent studies have shown that mammalian milk represents a continuous supply of commensal bacteria, including enterococci. The objectives of this study were to evaluate the presence of enterococci in milk of different species and to screen them for several genetic and phenotypic traits of clinical significance among enterococci. Results Samples were obtained from, at least, nine porcine, canine, ovine, feline and human healthy hosts. Enterococci could be isolated, at a concentration of 1.00 × 102 -1.16 × 103 CFU/ml, from all the porcine samples and, also from 85, 50, 25 and 25% of the human, canine, feline and ovine ones, respectively. They were identified as Enterococcus faecalis, Enterococcus faecium, Enterococcus hirae, Enterococcus casseliflavus and Enterococcus durans. Among the 120 initial enterococcal isolates, 36 were selected on the basis of their different PFGE profiles and further characterized. MLST analysis revealed a wide diversity of STs among the E. faecalis and E. faecium strains, including some frequently associated to hospital infections and novel STs. All the E. faecalis strains possessed some of the potential virulence determinants (cad, ccf, cob, cpd, efaAfs, agg2, gelE, cylA, espfs) assayed while the E. faecium ones only harboured the efaAfm gene. All the tested strains were susceptible to tigecycline, linezolid and vancomycin, and produced tyramine. Their susceptibility to the rest of the antimicrobials and their ability to produce other biogenic amines varied depending on the strain. Enterococci strains isolated from porcine samples showed the widest spectrum of antibiotic resistance. Conclusions Enterococci isolated from milk of different mammals showed a great genetic diversity. The wide distribution of virulence genes and/or antibiotic resistance among the E. faecalis and E. faecium isolates indicates that they can constitute a reservoir of such traits and a risk to animal and human health. PMID:24325647

  9. Repression of Antibiotic Production and Sporulation in Streptomyces coelicolor by Overexpression of a TetR Family Transcriptional Regulator ▿ †

    PubMed Central

    Xu, Delin; Seghezzi, Nicolas; Esnault, Catherine; Virolle, Marie-Joelle

    2010-01-01

    The overexpression of a regulatory gene of the TetR family (SCO3201) originating either from Streptomyces lividans or from Streptomyces coelicolor was shown to strongly repress antibiotic production (calcium-dependent antibiotic [CDA], undecylprodigiosin [RED], and actinorhodin [ACT]) of S. coelicolor and of the ppk mutant strain of S. lividans. Curiously, the overexpression of this gene also had a strong inhibitory effect on the sporulation process of S. coelicolor but not on that of S. lividans. SCO3201 was shown to negatively regulate its own transcription, and its DNA binding motif was found to overlap its −35 promoter sequence. The interruption of this gene in S. lividans or S. coelicolor did not lead to any obvious phenotypes, indicating that when overexpressed SCO3201 likely controls the expression of target genes of other TetR regulators involved in the regulation of the metabolic and morphological differentiation process in S. coelicolor. The direct and functional interaction of SCO3201 with the promoter region of scbA, a gene under the positive control of the TetR-like regulator, ScbR, was indeed demonstrated by in vitro as well as in vivo approaches. PMID:20935121

  10. Antibiotic Multiresistance Analysis of Mesophilic and Psychrotrophic Pseudomonas spp. Isolated from Goat and Lamb Slaughterhouse Surfaces throughout the Meat Production Process

    PubMed Central

    Lavilla Lerma, Leyre; Benomar, Nabil; Casado Muñoz, María del Carmen; Gálvez, Antonio

    2014-01-01

    The aim of this study was to investigate the phenotypic and genotypic antibiotic resistance profiles of pseudomonads isolated from surfaces of a goat and lamb slaughterhouse, which were representative of areas that are possible sources of meat contamination. Mesophilic (85 isolates) and psychrotrophic (37 isolates) pseudomonads identified at the species level generally were resistant to sulfamethoxazole, erythromycin, amoxicillin, ampicillin, chloramphenicol, trimethoprim, rifampin, and ceftazidime (especially mesophiles), as well as colistin and tetracycline (especially psychrotrophes). However, they generally were sensitive to ciprofloxacin, gentamicin, imipenem, and kanamycin regardless of species identity. Worryingly, in the present study, we found multidrug resistance (MDR) to up to 13 antibiotics, which was related to intrinsic and acquired resistance mechanisms. Furthermore, a link between various antimicrobial resistance genes was shown for beta-lactams and tetracycline, trimethoprim, and sulfonamides. The distribution and resistome-based analysis of MDR pseudomonads in different slaughterhouse zones indicated that the main sources of the identical or related pseudomonad strains were the animals (feet and wool) and the slaughterhouse environment, being disseminated from the beginning, or entrance environment, to the environment of the finished meat products. Those facts must be taken into consideration to avoid cross-contamination with the subsequent flow of mobile resistance determinants throughout all slaughterhouse zones and then to humans and the environment by the application of adequate practices of hygiene and disinfection measures, including those for animal wool and feet and also the entrance environment. PMID:25172860

  11. Antibiotic multiresistance analysis of mesophilic and psychrotrophic Pseudomonas spp. isolated from goat and lamb slaughterhouse surfaces throughout the meat production process.

    PubMed

    Lavilla Lerma, Leyre; Benomar, Nabil; Casado Muñoz, María del Carmen; Gálvez, Antonio; Abriouel, Hikmate

    2014-11-01

    The aim of this study was to investigate the phenotypic and genotypic antibiotic resistance profiles of pseudomonads isolated from surfaces of a goat and lamb slaughterhouse, which were representative of areas that are possible sources of meat contamination. Mesophilic (85 isolates) and psychrotrophic (37 isolates) pseudomonads identified at the species level generally were resistant to sulfamethoxazole, erythromycin, amoxicillin, ampicillin, chloramphenicol, trimethoprim, rifampin, and ceftazidime (especially mesophiles), as well as colistin and tetracycline (especially psychrotrophes). However, they generally were sensitive to ciprofloxacin, gentamicin, imipenem, and kanamycin regardless of species identity. Worryingly, in the present study, we found multidrug resistance (MDR) to up to 13 antibiotics, which was related to intrinsic and acquired resistance mechanisms. Furthermore, a link between various antimicrobial resistance genes was shown for beta-lactams and tetracycline, trimethoprim, and sulfonamides. The distribution and resistome-based analysis of MDR pseudomonads in different slaughterhouse zones indicated that the main sources of the identical or related pseudomonad strains were the animals (feet and wool) and the slaughterhouse environment, being disseminated from the beginning, or entrance environment, to the environment of the finished meat products. Those facts must be taken into consideration to avoid cross-contamination with the subsequent flow of mobile resistance determinants throughout all slaughterhouse zones and then to humans and the environment by the application of adequate practices of hygiene and disinfection measures, including those for animal wool and feet and also the entrance environment. PMID:25172860

  12. Biosynthesis of high molecular weight polylactosamine-type glycopeptides in rat Zajdela hepatoma ascites cells.

    PubMed

    Saunier, B; Goulut, C; Nato, F; Bourrillon, R

    1989-05-10

    The first steps of the biosynthetic pathway of high molecular weight polylactosamine-type glycopeptides from rat Zajdela hepatoma cells were studied by pulse-chase experiments, biochemical analysis and by inhibition of N-glycosylation. It is clear that this process involves firstly the transfer of a lipid-linked high-mannose oligosaccharide precursor to a protein moiety in a similar way to that of N-linked glycopeptides of a more common size range according to the classical 'cycle of dolichol'. In the presence of enzymes which are inhibitors of the processing of high-mannose oligosaccharide chains, this class of oligosaccharides was considerably increased, whereas polylactosamine chains and lower complex N-linked glycopeptides were concomitantly decreased in the same kinetics and the same ratio. As expected in the presence of N-methyldeoxynojirimycin, which is an alpha-glucosidase inhibitor, high-mannose oligosaccharides remained glycosylated and are mostly of the Glc1-3Man9GlcNAc type. In the presence of swainsonine, which is an alpha-mannosidase (EC 3.2.1.24) inhibitor, these chains were devoid of glucose residues. In addition, some chains displayed hybrid structures. It appears, therefore, that the first steps of the biosynthesis of polylactosamine-type and N-linked oligosaccharides of a more common size range proceed similarly and that differences between their biosynthetic pathways occur during the elongation phase, which leads to their final respective structures. Glycopeptides prepared from the cell surface by mild trypsin treatment as well as from entire cells, previously treated or not by processing inhibitors, display the same gel filtration patterns indicating that modifications in protein glycosylation do not prevent glycoprotein insertion into the cell membrane. PMID:2713399

  13. Tolerance to the Glycopeptides Vancomycin and Teicoplanin in Coagulase-Negative Staphylococci▿

    PubMed Central

    Bourgeois, Ingrid; Pestel-Caron, Martine; Lemeland, Jean-Francois; Pons, Jean-Louis; Caron, Francois

    2007-01-01

    Tolerance to vancomycin and teicoplanin in 90 clinical isolates of coagulase-negative staphylococci (CoNS) was investigated by time-kill curve methodology. Only six strains, belonging to the Staphylococcus lugdunensis species, exhibited tolerance. The seven other S. lugdunensis strains tested displayed weak susceptibility to the bactericidal activity of glycopeptides compared to the other CoNS. These phenomena are of concern, since S. lugdunensis is recognized as one of the most pathogenic CoNS. PMID:17116684

  14. Oligosaccharide structure and amino acid sequence of the major glycopeptides of mature human. beta. -hexosaminidase

    SciTech Connect

    O'Dowd, B.F.; Cumming, D.A.; Gravel, R.A.; Mahuran, D.

    1988-07-12

    Human ..beta..-hexosaminidase is a lysosomal enzyme that hydrolyzes terminal N-acetylhexosamines from GM/sub 2/ ganglioside, oligosaccharides, and other carbohydrate-containing macromolecules. There are two major forms of hexosaminidase: hexosaminidase A, with the structure ..cap alpha..(..beta../sub a/..beta../sub b/), and hexosaminidase B, 2(..beta../sub a/..beta../sub b/). Like other lysosomal proteins, hexosaminidase is targeted to its destination via glycosylation and processing in the rough endoplasmic reticulum and Golgi apparatus. Phosphorylation of specific mannose residues allows binding of the protein to the phosphomannosyl receptor and transfer to the lysosome. In order to define the structure and placement of the oligosaccharides in mature hexosaminidase and thus identify candidate mannose 6-phosphate recipient sites, the major tryptic/chymotryptic glycopeptides from each isozyme were purified by reverse-phase high-performance liquid chromatography. Two major concanavalin A binding glycopeptides, localized to the ..beta../sub b/f chain, and one non concanavalin A binding glycopeptide, localized to the ..beta../sub a/ chain, were found associated with the ..beta..-subunit in both hexosaminidase A and hexosaminidase B. The oligosaccharide structures were determined by nuclear magnetic resonance spectrometry. The unique glycopeptide associated with the ..beta../sub a/ chain contained a single GlcNAc residue. Thus all three mature polypeptides comprising the ..cap alpha.. and ..beta.. subunits of hexosaminidase contain carbohydrate, the structures of which have the appearance of being partially degraded in the lysosome. In the ..cap alpha.. chain they found only one possible site for in vivo phosphorylation. In the ..beta.. it is unclear if only one or all three of the sites could have contained phosphate. However, mature placental hexosaminidase A and B can be rephosphorylated in vitro. This requires the presence of an oligosaccharide containing an ..cap

  15. Automated Glycan Sequencing from Tandem Mass Spectra of N-Linked Glycopeptides.

    PubMed

    Yu, Chuan-Yih; Mayampurath, Anoop; Zhu, Rui; Zacharias, Lauren; Song, Ehwang; Wang, Lei; Mechref, Yehia; Tang, Haixu

    2016-06-01

    Mass spectrometry has become a routine experimental tool for proteomic biomarker analysis of human blood samples, partly due to the large availability of informatics tools. As one of the most common protein post-translational modifications (PTMs) in mammals, protein glycosylation has been observed to alter in multiple human diseases and thus may potentially be candidate markers of disease progression. While mass spectrometry instrumentation has seen advancements in capabilities, discovering glycosylation-related markers using existing software is currently not straightforward. Complete characterization of protein glycosylation requires the identification of intact glycopeptides in samples, including identification of the modification site as well as the structure of the attached glycans. In this paper, we present GlycoSeq, an open-source software tool that implements a heuristic iterated glycan sequencing algorithm coupled with prior knowledge for automated elucidation of the glycan structure within a glycopeptide from its collision-induced dissociation tandem mass spectrum. GlycoSeq employs rules of glycosidic linkage as defined by glycan synthetic pathways to eliminate improbable glycan structures and build reasonable glycan trees. We tested the tool on two sets of tandem mass spectra of N-linked glycopeptides cell lines acquired from breast cancer patients. After employing enzymatic specificity within the N-linked glycan synthetic pathway, the sequencing results of GlycoSeq were highly consistent with the manually curated glycan structures. Hence, GlycoSeq is ready to be used for the characterization of glycan structures in glycopeptides from MS/MS analysis. GlycoSeq is released as open source software at https://github.com/chpaul/GlycoSeq/ . PMID:27111718

  16. Fate and transport of veterinary antibiotics, antibiotic-resistant bacteria, and antibiotic resistance gene from fields receiving poultry manure during storm events

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antimicrobials are used in production agriculture to treat disease and promote animal growth, but the presence of antibiotics in the environment raises concern about widespread antibiotic resistance. This study documents the occurrence and transport of tylosin, tetracycline, enterococci resistant to...

  17. Isolation and Structure Characterization of an Antioxidative Glycopeptide from Mycelial Culture Broth of a Medicinal Fungus

    PubMed Central

    Wu, Jian-Yong; Chen, Xia; Siu, Ka-Chai

    2014-01-01

    A novel glycopeptide (Cs-GP1) with an average molecular weight (Mw) of 6.0 kDa was isolated and purified by column chromatography from the lower Mw fraction of exopolysaccharide (EPS) produced by a medicinal fungus Cordyceps sinensis Cs-HK1. Its carbohydrate moiety was mainly composed of glucose and mannose at 3.2:1.0 mole ratio, indicating an O-linked glycopeptide. The peptide chain contained relatively high mole ratios of aspartic acid, glutamic acid and glycine (3.3–3.5 relative to arginine) but relatively low ratios of tyrosine and histidine. The peptide chain sequence analyzed after trypsin digestion by LC-MS was KNGIFQFGEDCAAGSISHELGGFREFREFLKQAGLE. Cs-GP1 exhibited remarkable antioxidant capacity with a Trolox equivalent antioxidant capacity of 1183.8 μmol/g and a ferric reducing ability of 611.1 μmol Fe(II)/g, and significant protective effect against H2O2-induced PC12 cell injury at a minimum dose of 10 μg/mL. This is the first report on the structure and bioactivity of an extracellular glycopeptide from the Cordyceps species. PMID:25268609

  18. Isolation and structure characterization of an antioxidative glycopeptide from mycelial culture broth of a medicinal fungus.

    PubMed

    Wu, Jian-Yong; Chen, Xia; Siu, Ka-Chai

    2014-01-01

    A novel glycopeptide (Cs-GP1) with an average molecular weight (Mw) of 6.0 kDa was isolated and purified by column chromatography from the lower Mw fraction of exopolysaccharide (EPS) produced by a medicinal fungus Cordyceps sinensis Cs-HK1. Its carbohydrate moiety was mainly composed of glucose and mannose at 3.2:1.0 mole ratio, indicating an O-linked glycopeptide. The peptide chain contained relatively high mole ratios of aspartic acid, glutamic acid and glycine (3.3-3.5 relative to arginine) but relatively low ratios of tyrosine and histidine. The peptide chain sequence analyzed after trypsin digestion by LC-MS was KNGIFQFGEDCAAGSISHELGGFREFREFLKQAGLE. Cs-GP1 exhibited remarkable antioxidant capacity with a Trolox equivalent antioxidant capacity of 1183.8 μmol/g and a ferric reducing ability of 611.1 μmol Fe(II)/g, and significant protective effect against H2O2-induced PC12 cell injury at a minimum dose of 10 μg/mL. This is the first report on the structure and bioactivity of an extracellular glycopeptide from the Cordyceps species. PMID:25268609

  19. Analysis of ER-associated glycoprotein degradation using synthetic glycopeptide probes

    SciTech Connect

    Hagihara, Shinya; Goda, Kazuhito; Matsuo, Ichiro; Ito, Yukishige . E-mail: yukito@riken.jp

    2007-08-24

    Quality control of proteins is an essential process for maintaining normal cell activity. It ensures that only correctly folded proteins are produced and terminally misfolded proteins are eliminated by degradation. ER-associated degradation (ERAD) of misfolded proteins is an important aspect of protein quality control system. Recent studies have revealed that glycoprotein glycans play significant roles in this process. It includes polyubiquitination, deglycosylation, and proteasomal degradation. In the present study, a systematic analysis of these steps was carried out using chemically synthesized glycopeptides. We revealed that N-linked glycopeptides are degraded by 20S proteasome, but with drastically reduced rate compared to non-glycosylated peptide. This result strongly suggests that deglycosylating activity of peptide:N-glycanase (PNGase) is important for the facile degradation of glycoproteins. Our study showed, for the first time, that PNGase cleaves truncated glycans as short as chitobiose from peptide. However, this cleavage required the presence of hydrophobic region nearby N-glycosylation site. Furthermore, analysis of interactions with F-box protein Fbs1 was conducted with fluorescent correlation spectroscopy (FCS). It was shown that the presence of Fbs1 perturb the activity of PNGase toward high-mannose-type glycopeptides.

  20. Glycoproteomic Analysis of Malignant Ovarian Cancer Ascites Fluid Identifies Unusual Glycopeptides.

    PubMed

    Miyamoto, Suzanne; Ruhaak, L Renee; Stroble, Carol; Salemi, Michelle R; Phinney, Brett; Lebrilla, Carlito B; Leiserowitz, Gary S

    2016-09-01

    Ovarian cancer is a major cause of cancer mortality among women, largely due to late diagnosis of advanced metastatic disease. More extensive molecular analysis of metastatic ovarian cancer is needed to identify post-translational modifications of proteins, especially glycosylation that is particularly associated with metastatic disease to better understand the metastatic process and identify potential therapeutic targets. Glycoproteins in ascites fluid were enriched by affinity binding to lectins (ConA or WGA) and other affinity matrices. Separate glycomic, proteomic, and glycopeptide analyses were performed. Relative abundances of different N-glycan groups and proteins were identified from ascites fluids and a serum control. Levels of biomarkers CA125, MUC1, and fibronectin were also monitored in OC ascites samples by Western blot analysis. N-Glycan analysis of ascites fluids showed the presence of large, highly fucosylated and sialylated complex and hybrid glycans, some of which were not observed in normal serum. OC ascites glycoproteins, haptoglobin, fibronectin, lumican, fibulin, hemopexin, ceruloplasmin, alpha-1-antitrypsin, and alpha-1-antichymotrypsin were more abundant in OC ascites or not present in serum control samples. Further glycopeptide analysis of OC ascites identified N- and O-glycans in clusterin, hemopexin, and fibulin glycopeptides, some of which are unusual and may be important in OC metastasis. PMID:27500424

  1. Cotton HILIC SPE microtips for microscale purification and enrichment of glycans and glycopeptides.

    PubMed

    Selman, Maurice H J; Hemayatkar, Mahdi; Deelder, André M; Wuhrer, Manfred

    2011-04-01

    Solid-phase extraction microtips are important devices in modern bioanalytics, as they allow miniaturized sample preparation for mass spectrometric analysis. Here we introduce the use of cotton wool for the preparation of filter-free HILIC SPE microtips. To this end, pieces of cotton wool pads (approximately 500 μg) were packed into 10 μL pipet tips. The performance of the tips was evaluated for microscale purification of tryptic IgG Fc N-glycopeptides. Cotton wool HILIC SPE microtips allowed the removal of salts, most nonglycosylated peptides, and detergents such as SDS from glycoconjugate samples. MALDI-TOF-MS glycopeptide profiles were very repeatable with different tips as well as reused tips, and very similar profiles were obtained with different brands of cotton wool pads. In addition, we used cotton HILIC microtips to purify N-glycans after N-glycosidase F treatment of IgG and transferrin followed by MALDI-TOF-MS detection. In conclusion, we establish cotton wool microtips for glycan and glycopeptide purification with subsequent mass spectrometric detection. PMID:21366235

  2. The Double Life of Antibiotics

    PubMed Central

    Yap, Mee-Ngan F.

    2013-01-01

    Antibiotic resistance is a persistent health care problem worldwide. Evidence for the negative consequences of subtherapeutic feeding in livestock production has been mounting while the antibiotic pipeline is drying up. In recent years, there has been a paradigm shift in our perception of antibiotics. Apart from its roles in self-defense, antibiotics also serve as inter-microbial signaling molecules, regulators of gene expression, microbial food sources, and as mediators of host immune response. “The time may come when penicillin can be bought by anyone in the shops. Then there is the danger that the ignorant man may easily under-dose himself and by exposing his microbes to nonlethal quantities of the drug make them resistant.”~Alexander Fleming PMID:24003650

  3. Resistance-induced antibiotic substitution.

    PubMed

    Howard, David H

    2004-06-01

    In many cases, physicians prescribe antibiotics without knowing whether an individual patient is infected with a susceptible or resistant pathogen. As the proportion of resistant organisms in a community increases, physicians substitute away from older-inexpensive drugs to newer, more expensive agents as first line therapy. This paper explores the implications of resistance-induced antibiotic substitution for epidemiological models to predict future resistance levels, efforts to measure the health care costs associated with resistance, and policies to improve physicians' antibiotic prescribing decisions. The extent of resistance-induced substitution in outpatient settings is documented using a data set consisting of observations on initial physician office visits for otitis media in the US controlling for new product introductions and price increases, per prescription antibiotic spending increased by 22% between 1980 and 1996, corresponding to a steep increase in resistance levels over the same period. PMID:15185388

  4. Vancomycin production is enhanced in chemostat culture with biomass-recycle.

    PubMed

    McIntyre, J J; Bunch, A W; Bull, A T

    1999-03-01

    Production of the glycopeptide antibiotic vancomycin by Amycolatopsis orientalis ATCC 19795 was examined in phosphate-limited chemostat cultures with biomass-recycle, employing an oscillating membrane separator, at a constant dilution rate (D= 0. 14 h-1). Experiments made under low agitation conditions (600 rpm) showed that the biomass concentration could be increased 3.9-fold with vancomycin production kinetics very similar to that of chemostat culture without biomass-recycle. The specific production rate (qvancomycin) was maximal when the biomass-recycle ratio (R) was 0.13 (D= 0.087 h-1). When the dissolved oxygen tension dropped below 20% (air saturation), the biomass and vancomycin concentrations decreased and an unidentified red metabolite was released into the culture medium. Using increased agitation (850 rpm), used to maintain the dissolved oxygen tension above 20% air saturation, maximum increases in biomass concentration (7.9-fold) and vancomcyin production 1.6-fold (0.6 mg/g dry weight/h) were obtained when R was 0.44 (D= 0.056 h -1) compared to chemostat culture without biomass-recycle. Moreover, at this latter recycle ratio the volumetric vancomycin production rate was 14.7 mg/L/h (a 7-fold increase compared to chemostat culture without biomass-recycle). These observations encourage further research on biomass-recycling as a means of optimising the production of antibiotics. PMID:10099566

  5. Antibiotic Resistance Determinants in a Pseudomonas putida Strain Isolated from a Hospital

    PubMed Central

    Duque, Estrella; Fernández, Matilde; Molina-Santiago, Carlos; Roca, Amalia; Porcel, Mario; de la Torre, Jesús; Segura, Ana; Plesiat, Patrick; Jeannot, Katy; Ramos, Juan-Luis

    2014-01-01

    Environmental microbes harbor an enormous pool of antibiotic and biocide resistance genes that can impact the resistance profiles of animal and human pathogens via horizontal gene transfer. Pseudomonas putida strains are ubiquitous in soil and water but have been seldom isolated from humans. We have established a collection of P. putida strains isolated from in-patients in different hospitals in France. One of the isolated strains (HB3267) kills insects and is resistant to the majority of the antibiotics used in laboratories and hospitals, including aminoglycosides, ß-lactams, cationic peptides, chromoprotein enediyne antibiotics, dihydrofolate reductase inhibitors, fluoroquinolones and quinolones, glycopeptide antibiotics, macrolides, polyketides and sulfonamides. Similar to other P. putida clinical isolates the strain was sensitive to amikacin. To shed light on the broad pattern of antibiotic resistance, which is rarely found in clinical isolates of this species, the genome of this strain was sequenced and analysed. The study revealed that the determinants of multiple resistance are both chromosomally-borne as well as located on the pPC9 plasmid. Further analysis indicated that pPC9 has recruited antibiotic and biocide resistance genes from environmental microorganisms as well as from opportunistic and true human pathogens. The pPC9 plasmid is not self-transmissible, but can be mobilized by other bacterial plasmids making it capable of spreading antibiotic resistant determinants to new hosts. PMID:24465371

  6. Antibiotic resistance determinants in a Pseudomonas putida strain isolated from a hospital.

    PubMed

    Molina, Lázaro; Udaondo, Zulema; Duque, Estrella; Fernández, Matilde; Molina-Santiago, Carlos; Roca, Amalia; Porcel, Mario; de la Torre, Jesús; Segura, Ana; Plesiat, Patrick; Jeannot, Katy; Ramos, Juan-Luis

    2014-01-01

    Environmental microbes harbor an enormous pool of antibiotic and biocide resistance genes that can impact the resistance profiles of animal and human pathogens via horizontal gene transfer. Pseudomonas putida strains are ubiquitous in soil and water but have been seldom isolated from humans. We have established a collection of P. putida strains isolated from in-patients in different hospitals in France. One of the isolated strains (HB3267) kills insects and is resistant to the majority of the antibiotics used in laboratories and hospitals, including aminoglycosides, ß-lactams, cationic peptides, chromoprotein enediyne antibiotics, dihydrofolate reductase inhibitors, fluoroquinolones and quinolones, glycopeptide antibiotics, macrolides, polyketides and sulfonamides. Similar to other P. putida clinical isolates the strain was sensitive to amikacin. To shed light on the broad pattern of antibiotic resistance, which is rarely found in clinical isolates of this species, the genome of this strain was sequenced and analysed. The study revealed that the determinants of multiple resistance are both chromosomally-borne as well as located on the pPC9 plasmid. Further analysis indicated that pPC9 has recruited antibiotic and biocide resistance genes from environmental microorganisms as well as from opportunistic and true human pathogens. The pPC9 plasmid is not self-transmissible, but can be mobilized by other bacterial plasmids making it capable of spreading antibiotic resistant determinants to new hosts. PMID:24465371

  7. Study of Antibiotic Resistance Pattern in Methicillin Resistant Staphylococcus Aureus with Special Reference to Newer Antibiotic.

    PubMed

    Kaur, Dardi Charan; Chate, Sadhana Sanjay

    2015-01-01

    The worldwide epidemic of antibiotic resistance is in danger of ending the golden age of antibiotic therapy. Resistance impacts on all areas of medicine, and is making successful empirical therapy much more difficult to achieve. Staphylococcus aureus demonstrates a unique ability to quickly respond to each new antibiotic with the development of a resistance mechanism, starting with penicillin, until the most recent, linezolid and daptomycin. Methicillin resistant S. aureus (MRSA) has become endemic today in hospitals worldwide. Resistance to the newer antimicrobial-agents - linezolid, vancomycin, teicoplanin, and daptomycin are been reported and also the fear of pandrug-resistance. This study was carried out to know the antimicrobial resistant pattern of MRSA to newer antibiotic, to know any isolates are extensively-drug resistant (XDR)/pandrug resistant (PDR), inducible macrolide-lincosamide streptogramin B (iMLSB), and mupirocin resistance. Thirty-six MRSA isolates resistant to the routinely tested antibiotic were further tested for list of antibiotic by a group of international experts. Isolates were tested for iMLSB and mupirocin resistance by the disk diffusion method. Of 385 MRSA, 36 (9.35%) isolates of MRSA were resistant to the routinely tested antibiotic. Among these 36 MRSA isolates, none of our isolates were XDR/PDR or showed resistant to anti-MRSA cephalosporins (ceftaroline), phosphonic acids, glycopeptides, glycylcyclines, and fucidanes. Lower resistance was seen in oxazolidinones (2.78%), streptogramins (5.56%), lipopeptide (5.56%). Thirty-four (94.44%) isolates showed constitutive MLSB (cMLSB) resistance and two (5.56%) iMLSB phenotypes. High- and low-level mupirocin resistance were seen in 13 (36.11%) and six (16.67%), respectively. In our study, none of our isolates were XDR or PDR. No resistance was observed to ceftaroline, telavancin, teicoplanin, and vancomycin; but the presence of linezolid resistance (1, 2.28%) and daptomycin resistance (2, 5

  8. Study of Antibiotic Resistance Pattern in Methicillin Resistant Staphylococcus Aureus with Special Reference to Newer Antibiotic

    PubMed Central

    Kaur, Dardi Charan; Chate, Sadhana Sanjay

    2015-01-01

    The worldwide epidemic of antibiotic resistance is in danger of ending the golden age of antibiotic therapy. Resistance impacts on all areas of medicine, and is making successful empirical therapy much more difficult to achieve. Staphylococcus aureus demonstrates a unique ability to quickly respond to each new antibiotic with the development of a resistance mechanism, starting with penicillin, until the most recent, linezolid and daptomycin. Methicillin resistant S. aureus (MRSA) has become endemic today in hospitals worldwide. Resistance to the newer antimicrobial-agents — linezolid, vancomycin, teicoplanin, and daptomycin are been reported and also the fear of pandrug-resistance. This study was carried out to know the antimicrobial resistant pattern of MRSA to newer antibiotic, to know any isolates are extensively-drug resistant (XDR)/pandrug resistant (PDR), inducible macrolide-lincosamide streptogramin B (iMLSB), and mupirocin resistance. Thirty-six MRSA isolates resistant to the routinely tested antibiotic were further tested for list of antibiotic by a group of international experts. Isolates were tested for iMLSB and mupirocin resistance by the disk diffusion method. Of 385 MRSA, 36 (9.35%) isolates of MRSA were resistant to the routinely tested antibiotic. Among these 36 MRSA isolates, none of our isolates were XDR/PDR or showed resistant to anti-MRSA cephalosporins (ceftaroline), phosphonic acids, glycopeptides, glycylcyclines, and fucidanes. Lower resistance was seen in oxazolidinones (2.78%), streptogramins (5.56%), lipopeptide (5.56%). Thirty-four (94.44%) isolates showed constitutive MLSB (cMLSB) resistance and two (5.56%) iMLSB phenotypes. High- and low-level mupirocin resistance were seen in 13 (36.11%) and six (16.67%), respectively. In our study, none of our isolates were XDR or PDR. No resistance was observed to ceftaroline, telavancin, teicoplanin, and vancomycin; but the presence of linezolid resistance (1, 2.28%) and daptomycin resistance (2

  9. Penetration barrier contributes to bacterial biofilm-associated resistance against only select antibiotics, and exhibits genus-, strain- and antibiotic-specific differences.

    PubMed

    Singh, Rachna; Sahore, Simmi; Kaur, Preetinder; Rani, Alka; Ray, Pallab

    2016-08-01

    Bacterial biofilms are implicated in a wide range of implant-based and chronic infections. These infections are often associated with adverse therapeutic outcomes, owing to the decreased antibiotic susceptibility of biofilms compared with their planktonic counterparts. This altered biofilm susceptibility has been attributed to multiple factors, including a reduced antibiotic penetration. Although several studies have addressed the role of penetration barrier in biofilm-associated drug resistance, it remains inconclusive. This study was done to elucidate antibiotic penetration through biofilms formed by Staphylococcus aureus, S. epidermidis, Escherichia coli and Klebsiella pneumoniae, using an agar disk diffusion assay. Penetration capacity of six antimicrobial drugs from different classes (β-lactams, aminoglycosides, tetracyclines, phenicols, fluoroquinolones and glycopeptides) through biofilms formed by standard strains and clinical isolates from catheter-related bloodstream infections (CRBSI) was elucidated by measuring their growth-inhibition zones in lawn cultures on Mueller-Hinton agar, following diffusion of an antibiotic from an overlying disk through their biofilm to the agar medium. Penetration of only select antimicrobials (vancomycin and chloramphenicol) was hindered through biofilms. There was considerable variation in biofilm-permeating capacity depending upon the genus, strain/CRBSI isolate and antibiotic tested. Furthermore, antibiotics failed to kill the biofilm cells independent of penetration, indicating that other factors contributed substantially to biofilm resistance. PMID:27402781

  10. The ppGpp synthetase gene (relA) of Streptomyces coelicolor A3(2) plays a conditional role in antibiotic production and morphological differentiation.

    PubMed Central

    Chakraburtty, R; Bibb, M

    1997-01-01

    Deletion of most of the coding region of the ppGpp synthetase gene (relA) of Streptomyces coelicolor A3(2) resulted in loss of ppGpp synthesis, both upon entry into stationary phase under conditions of nitrogen limitation and following amino acid starvation during exponential growth, but had no effect on growth rate. The relA mutant, which showed continued rRNA synthesis upon amino acid depletion (the relaxed response), failed to produce the antibiotics undecylprodigiosin (Red) and actinorhodin (Act) under conditions of nitrogen limitation. The latter appears to reflect diminished transcription of pathway-specific regulatory genes for Red and Act production, redD and actII-ORF4, respectively. In addition to the changes in secondary metabolism, the relA mutant showed a marked delay in the onset and extent of morphological differentiation, resulting in a conspicuously altered colony morphology. PMID:9294445

  11. Structure elucidation of degradation products of the antibiotic amoxicillin with ion trap MS(n) and accurate mass determination by ESI TOF.

    PubMed

    Nägele, Edgar; Moritz, Ralf

    2005-10-01

    Today, it is necessary to identify relevant compounds appearing in discovery and development of new drug substances in the pharmaceutical industry. For that purpose, the measurement of accurate molecular mass and empirical formula calculation is very important for structure elucidation in addition to other available analytical methods. In this work, the identification and confirmation of degradation products in a finished dosage form of the antibiotic drug amoxicillin obtained under stress conditions will be demonstrated. Structure elucidation is performed utilizing liquid chromatography (LC) ion trap MS/MS and MS3 together with accurate mass measurement of the molecular ions and of the collision induced dissociation (CID) fragments by liquid chromatography electro spray ionization time-of-flight mass spectrometry (LC/ESI-TOF). PMID:16099170

  12. Gold nanoparticles immobilized hydrophilic monoliths with variable functional modification for highly selective enrichment and on-line deglycosylation of glycopeptides.

    PubMed

    Liang, Yu; Wu, Ci; Zhao, Qun; Wu, Qi; Jiang, Bo; Weng, Yejing; Liang, Zhen; Zhang, Lihua; Zhang, Yukui

    2015-11-01

    The poly (glycidyl methacrylate-co-poly (ethylene glycol) diacrylate) monoliths modified with gold nanoparticles, with advantages of enhanced reactive sites, good hydrophilicity and facile modification, were prepared as the matrix, followed by variable functionalization with cysteine and PNGase F for glycopeptide enrichment and on-line deglycosylation respectively. By the cysteine functionalized monolithic column, glycopeptides could be efficiently and selectively enriched with good reproducibility based on hydrophilic interaction chromatography (HILIC). Furthermore, the enrichment was specially achieved in weak alkaline environment, with 10 mM NH4HCO3 as the elution buffer, compatible with deglycosylation conditions. Therefore, the glycopeptides could be on-line deglycosylated with high efficiency and throughput by directly coupling the PNGase F functionalized monolithic column with the enrichment column during elution without the requirement of buffer exchange and pH adjustment. By such a method, within only 70-min pretreatment, 196 N-linked glycopeptides, corresponding to 122 glycoproteins, could be identified from 5 μg of human plasma with 14 high-abundant proteins removed, and the N-linked glycopeptides occupied 81% of all identified peptides, achieving to the best of our knowledge, the highest selectivity of HILIC-based methods. All the results demonstrated the high efficiency, selectivity and throughput of our proposed strategy for the large scale glycoproteome analysis. PMID:26572842

  13. Antibiotics from predatory bacteria

    PubMed Central

    Korp, Juliane; Vela Gurovic, María S

    2016-01-01

    Summary Bacteria, which prey on other microorganisms, are commonly found in the environment. While some of these organisms act as solitary hunters, others band together in large consortia before they attack their prey. Anecdotal reports suggest that bacteria practicing such a wolfpack strategy utilize antibiotics as predatory weapons. Consistent with this hypothesis, genome sequencing revealed that these micropredators possess impressive capacities for natural product biosynthesis. Here, we will present the results from recent chemical investigations of this bacterial group, compare the biosynthetic potential with that of non-predatory bacteria and discuss the link between predation and secondary metabolism. PMID:27340451

  14. Antibiotics from predatory bacteria.

    PubMed

    Korp, Juliane; Vela Gurovic, María S; Nett, Markus

    2016-01-01

    Bacteria, which prey on other microorganisms, are commonly found in the environment. While some of these organisms act as solitary hunters, others band together in large consortia before they attack their prey. Anecdotal reports suggest that bacteria practicing such a wolfpack strategy utilize antibiotics as predatory weapons. Consistent with this hypothesis, genome sequencing revealed that these micropredators possess impressive capacities for natural product biosynthesis. Here, we will present the results from recent chemical investigations of this bacterial group, compare the biosynthetic potential with that of non-predatory bacteria and discuss the link between predation and secondary metabolism. PMID:27340451

  15. Hospital Acquired Pneumonia Due to Achromobacter spp. in a Geriatric Ward in China: Clinical Characteristic, Genome Variability, Biofilm Production, Antibiotic Resistance and Integron in Isolated Strains

    PubMed Central

    Liu, Chao; Pan, Fei; Guo, Jun; Yan, Weifeng; Jin, Yi; Liu, Changting; Qin, Long; Fang, Xiangqun

    2016-01-01

    Background: Hospital-acquired pneumonia (HAP) due to Achromobacter has become a substantial concern in recent years. However, HAP due to Achromobacter in the elderly is rare. Methods: A retrospective analysis was performed on 15 elderly patients with HAP due to Achromobacter spp., in which the sequence types (STs), integrons, biofilm production and antibiotic resistance of the Achromobacter spp. were examined. Results: The mean age of the 15 elderly patients was 88.8 ± 5.4 years. All patients had at least three underlying diseases and catheters. Clinical outcomes improved in 10 of the 15 patients after antibiotic and/or mechanical ventilation treatment, but three patients had chronic infections lasting more than 1 year. The mortality rate was 33.3% (5/15). All strains were resistant to aminoglycosides, aztreonam, nitrofurantoin, and third- and fourth-generation cephalosporins (except ceftazidime and cefoperazone). Six new STs were detected. The most frequent ST was ST306. ST5 was identified in two separate buildings of the hospital. ST313 showed higher MIC in cephalosporins, quinolones and carbapenems, which should be more closely considered in clinical practice. All strains produced biofilm and had integron I and blaOXA-114-like. The main type was blaOXA-114q. The variable region of integron I was different among strains, and the resistance gene of the aminoglycosides was most commonly inserted in integron I. Additionally, blaPSE-1 was first reported in this isolate. Conclusion: Achromobacter spp. infection often occurs in severely ill elders with underlying diseases. The variable region of integrons differs, suggesting that Achromobacter spp. is a reservoir of various resistance genes. PMID:27242678

  16. Diversity of Natural Product Biosynthetic Genes in the Microbiome of the Deep Sea Sponges Inflatella pellicula, Poecillastra compressa, and Stelletta normani.

    PubMed

    Borchert, Erik; Jackson, Stephen A; O'Gara, Fergal; Dobson, Alan D W

    2016-01-01

    Three different deep sea sponge species, Inflatella pellicula, Poecillastra compressa, and Stelletta normani comprising seven individual samples, retrieved from depths of 760-2900 m below sea level, were investigated using 454 pyrosequencing for their secondary metabolomic potential targeting adenylation domain and ketosynthase domain sequences. The data obtained suggest a diverse microbial origin of nonribosomal peptide synthetases and polyketide synthase fragments that in part correlates with their respective microbial community structures that were previously described and reveals an untapped source of potential novelty. The sequences, especially the ketosynthase fragments, display extensive clade formations which are clearly distinct from sequences hosted in public databases, therefore highlighting the potential of the microbiome of these deep sea sponges to produce potentially novel small-molecule chemistry. Furthermore, sequence similarities to gene clusters known to be involved in the production of many classes of antibiotics and toxins including lipopeptides, glycopeptides, macrolides, and hepatotoxins were also identified. PMID:27446062

  17. Diversity of Natural Product Biosynthetic Genes in the Microbiome of the Deep Sea Sponges Inflatella pellicula, Poecillastra compressa, and Stelletta normani

    PubMed Central

    Borchert, Erik; Jackson, Stephen A.; O’Gara, Fergal; Dobson, Alan D. W.

    2016-01-01

    Three different deep sea sponge species, Inflatella pellicula, Poecillastra compressa, and Stelletta normani comprising seven individual samples, retrieved from depths of 760–2900 m below sea level, were investigated using 454 pyrosequencing for their secondary metabolomic potential targeting adenylation domain and ketosynthase domain sequences. The data obtained suggest a diverse microbial origin of nonribosomal peptide synthetases and polyketide synthase fragments that in part correlates with their respective microbial community structures that were previously described and reveals an untapped source of potential novelty. The sequences, especially the ketosynthase fragments, display extensive clade formations which are clearly distinct from sequences hosted in public databases, therefore highlighting the potential of the microbiome of these deep sea sponges to produce potentially novel small-molecule chemistry. Furthermore, sequence similarities to gene clusters known to be involved in the production of many classes of antibiotics and toxins including lipopeptides, glycopeptides, macrolides, and hepatotoxins were also identified. PMID:27446062

  18. Fluorographic detection of tritiated glycopeptides and oligosaccharides separated on polyacrylamide gels: analysis of glycans from Dictyostelium discoideum glycoproteins

    SciTech Connect

    Prem Das, O.; Henderson, E.J.

    1986-11-01

    Previous workers have shown that oligosaccharides and glycopeptides can be separated by electrophoresis in buffers containing borate ions. However, normal fluorography of tritium-labeled structures cannot be performed because the glycans are soluble and can diffuse during equilibration with scintillants. This problem has been circumvented by equilibration of the gel with 2,5-diphenyloxazole (PPO) prior to electrophoresis. The presence of PPO in the gel during electrophoresis does not alter mobility of the glycopeptides and oligosaccharides. After electrophoresis, the gel is simply dried and fluorography performed. This allows sensitive and precise comparisons of labeled samples in parallel lanes of a slab gel and, since mobilities are highly reproducible, between different gels. The procedure is preparative in that after fluorography the gel bands can be quantitatively eluted for further study, without any apparent modification by the procedure. In this report, the procedure is illustrated by fractionation of both neutral and anionic glycopeptides produced by the cellular slime mold Dictyostelium discoideum.

  19. Systems, not pills: The options market for antibiotics seeks to rejuvenate the antibiotic pipeline.

    PubMed

    Brogan, David M; Mossialos, Elias

    2016-02-01

    Over the past decade, there has been a growing recognition of the increasing growth of antibiotic resistant bacteria and a relative decline in the production of novel antibacterial therapies. The combination of these two forces poses a potentially grave threat to global health, in both developed and developing countries. Current market forces do not provide appropriate incentives to stimulate new antibiotic development, thus we propose a new incentive mechanism: the Options Market for Antibiotics. This mechanism, modelled on the principle of financial call options, allows payers to buy the right, in early stages of development, to purchase antibiotics at a discounted price if and when they ever make it to market approval. This paper demonstrates the effect of such a model on the expected Net Present Value of a typical antibacterial project. As part of an integrated strategy to confront the impending antibiotic crisis, the Options Market for Antibiotics may effectively stimulate corporate and public investment into antibiotic research and development. PMID:26808335

  20. Trends of Antibiotic Consumption in Korea According to National Reimbursement Data (2008–2012)

    PubMed Central

    Yoon, Young Kyung; Park, Gi Chan; An, Hyonggin; Chun, Byung Chul; Sohn, Jang Wook; Kim, Min Ja

    2015-01-01

    Abstract This study determined the trends in the quantities and patterns of nationwide antibiotic consumption in the Republic of Korea (ROK). This nationwide descriptive epidemiological study was conducted in the ROK between 2008 and 2012. The quantities and patterns of total systemic antibiotic prescriptions were analyzed using National Health Insurance claims data collected through the Health Insurance Review and Assessment service. Data concerning systemic antibiotics were collected using measurement units of the defined daily dose (DDD) per 1000 people per day according to the Anatomical Therapeutic Chemical classification. Over the 5-year study period, the annual consumption of systemic antibiotics ranged from 21.68 to 23.12 DDD per 1000 people per day. Outpatient antibiotic use accounted for 80.9% of total consumption. A regression model with autoregressive errors showed significant increased consumption of major antibiotic subgroups, including 3rd-generation cephalosporins, carbapenems, and glycopeptides (P < 0.001). However, the antibiotic use of 1st- (P = 0.003), 2nd- (P = 0.004), and 3rd-generation (P = 0.018) cephalosporins among patients who underwent surgery under monitoring by the antimicrobial stewardship programs for perioperative prescription was significantly lower than in those who underwent surgery without monitoring programs. In time-series analysis, total antibiotic consumption demonstrated significant seasonality (P < 0.001). The consumption of broad-spectrum antibiotics was noted to have increased in the ROK from 2008 to 2012, providing a possible explanation for the changing epidemiology of multidrug resistance. Larger prospective studies are needed to investigate the impact on public health of monitoring programs of perioperative antibiotic usage. PMID:26579825

  1. The Art of Destruction: Optimizing Collision Energies in Quadrupole-Time of Flight (Q-TOF) Instruments for Glycopeptide-Based Glycoproteomics

    NASA Astrophysics Data System (ADS)

    Hinneburg, Hannes; Stavenhagen, Kathrin; Schweiger-Hufnagel, Ulrike; Pengelley, Stuart; Jabs, Wolfgang; Seeberger, Peter H.; Silva, Daniel Varón; Wuhrer, Manfred; Kolarich, Daniel

    2016-03-01

    In-depth site-specific investigations of protein glycosylation are the basis for understanding the biological function of glycoproteins. Mass spectrometry-based N- and O-glycopeptide analyses enable determination of the glycosylation site, site occupancy, as well as glycan varieties present on a particular site. However, the depth of information is highly dependent on the applied analytical tools, including glycopeptide fragmentation regimes and automated data analysis. Here, we used a small set of synthetic disialylated, biantennary N-glycopeptides to systematically tune Q-TOF instrument parameters towards optimal energy stepping collision induced dissociation (CID) of glycopeptides. A linear dependency of m/z-ratio and optimal fragmentation energy was found, showing that with increasing m/z-ratio, more energy is required for glycopeptide fragmentation. Based on these optimized fragmentation parameters, a method combining lower- and higher-energy CID was developed, allowing the online acquisition of glycan and peptide-specific fragments within a single tandem MS experiment. We validated this method analyzing a set of human immunoglobulins (IgA1+2, sIgA, IgG1+2, IgE, IgD, IgM) as well as bovine fetuin. These optimized fragmentation parameters also enabled software-assisted glycopeptide assignment of both N- and O-glycopeptides including information about the most abundant glycan compositions, peptide sequence and putative structures. Twenty-six out of 30 N-glycopeptides and four out of five O-glycopeptides carrying >110 different glycoforms could be identified by this optimized LC-ESI tandem MS method with minimal user input. The Q-TOF based glycopeptide analysis platform presented here opens the way to a range of different applications in glycoproteomics research as well as biopharmaceutical development and quality control.

  2. The Art of Destruction: Optimizing Collision Energies in Quadrupole-Time of Flight (Q-TOF) Instruments for Glycopeptide-Based Glycoproteomics.

    PubMed

    Hinneburg, Hannes; Stavenhagen, Kathrin; Schweiger-Hufnagel, Ulrike; Pengelley, Stuart; Jabs, Wolfgang; Seeberger, Peter H; Silva, Daniel Varón; Wuhrer, Manfred; Kolarich, Daniel

    2016-03-01

    In-depth site-specific investigations of protein glycosylation are the basis for understanding the biological function of glycoproteins. Mass spectrometry-based N- and O-glycopeptide analyses enable determination of the glycosylation site, site occupancy, as well as glycan varieties present on a particular site. However, the depth of information is highly dependent on the applied analytical tools, including glycopeptide fragmentation regimes and automated data analysis. Here, we used a small set of synthetic disialylated, biantennary N-glycopeptides to systematically tune Q-TOF instrument parameters towards optimal energy stepping collision induced dissociation (CID) of glycopeptides. A linear dependency of m/z-ratio and optimal fragmentation energy was found, showing that with increasing m/z-ratio, more energy is required for glycopeptide fragmentation. Based on these optimized fragmentation parameters, a method combining lower- and higher-energy CID was developed, allowing the online acquisition of glycan and peptide-specific fragments within a single tandem MS experiment. We validated this method analyzing a set of human immunoglobulins (IgA1+2, sIgA, IgG1+2, IgE, IgD, IgM) as well as bovine fetuin. These optimized fragmentation parameters also enabled software-assisted glycopeptide assignment of both N- and O-glycopeptides including information about the most abundant glycan compositions, peptide sequence and putative structures. Twenty-six out of 30 N-glycopeptides and four out of five O-glycopeptides carrying >110 different glycoforms could be identified by this optimized LC-ESI tandem MS method with minimal user input. The Q-TOF based glycopeptide analysis platform presented here opens the way to a range of different applications in glycoproteomics research as well as biopharmaceutical development and quality control. PMID:26729457

  3. Differential effects of immunosuppressants and antibiotics on human monoclonal antibody production in SCID mouse ascites by five heterohybridomas.

    PubMed

    Yoshinari, K; Arai, K

    1998-02-01

    SCID mice were inoculated with five human-mouse heterohybridomas derived by fusion of human lymph node lymphocytes from lung cancer patients with murine myeloma cells or human-mouse heteromyeloma cells, and the production of their human monoclonal antibodies (MAb) in the mouse ascites was investigated. In a comparison of the effects of pretreatment by i.p. (intraperitoneal) injection of pristane and anti-asialo GM1 serum on the antibody production of three of the hybridomas, pristane pretreatment resulted in substantial antibody production by all three, and pretreatment with anti-asialo GM1 serum resulted in similar or slightly lower levels of antibody production by two of the hybridomas but none by the third. In a second series of experiments using four of the hybridomas with pristane pretreatment, the co-injection of either penicillin G and streptomycin or kanamycin together with the hybridoma at the time of i.p. inoculation resulted in enhanced MAb production by the two heterohybridomas that had been propagated in medium containing hypoxanthine-aminopterin-thymidine (HAT) but not by the two that had been propagated in HAT-free medium. PMID:9523236

  4. Genetic variation and genomic context of antibiotic resistance genes and mobile genetic elements in Salmonella from animals and food production facilities

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: From 1998-2008, Salmonella was the most common bacterial cause of foodborne disease outbreaks and antibiotic resistant Salmonella are considered a serious threat when treatment is warranted. Both agricultural and clinical uses of antibiotics contribute to the development of resistant Sal...

  5. Spatial mapping of antibiotic resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A serious concern for modern animal production is the fear that feed antimicrobials, such as monensin, increase the potential for high levels of antibiotic resistant (AR) gene prevalence in the manure, which may subsequently be shared with soil communities and eventually be taken up by human pathoge...

  6. Exploring the self-assembly of glycopeptides using a diphenylalanine scaffold.

    PubMed

    Roytman, Rinat; Adler-Abramovich, Lihi; Kumar, K S Ajish; Kuan, Ting-Chun; Lin, Chun-Cheng; Gazit, Ehud; Brik, Ashraf

    2011-08-21

    Diphenylalanine, a key building block for organic nanotechnology, forms discrete, rigid and hollow nanotubes that are assembled spontaneously upon their dilution from organic phase into aqueous solution. Here we report the efficient preparation of several S-linked glycosylated diphenylalanine analogues bearing different monosaccharide, di-saccharide and sialic acid residues. The self-assembly studies revealed that these glycopeptides adopted various structures and glycosylation could be a tool to manipulate the self-assembly process. Moreover, the solubility of these analogues was found to be much greater than diphenylalanine, which could open new applications based on these nanostructures. PMID:21720631

  7. Glycopeptide-functionalized gold nanoparticles for antibody induction against the tumor associated mucin-1 glycoprotein.

    PubMed

    Cai, Hui; Degliangeli, Federica; Palitzsch, Björn; Gerlitzki, Bastian; Kunz, Horst; Schmitt, Edgar; Fiammengo, Roberto; Westerlind, Ulrika

    2016-03-01

    We report the preparation of gold nanoparticle (AuNP)-based vaccine candidates against the tumor-associated form of the mucin-1 (MUC1) glycoprotein. Chimeric peptides, consisting of a glycopeptide sequence derived from MUC1 and the T-cell epitope P30 sequence were immobilized on PEGylated AuNPs and the ability to induce selective antibodies in vivo was investigated. After immunization, mice showed significant MHC-II mediated immune responses and their antisera recognized human MCF-7 breast cancer cells. Nanoparticles designed according to this report may become key players in the development of anticancer vaccines. PMID:26853835

  8. Pleiotropic regulatory genes bldA, adpA and absB are implicated in production of phosphoglycolipid antibiotic moenomycin.

    PubMed

    Makitrynskyy, Roman; Ostash, Bohdan; Tsypik, Olga; Rebets, Yuriy; Doud, Emma; Meredith, Timothy; Luzhetskyy, Andriy; Bechthold, Andreas; Walker, Suzanne; Fedorenko, Victor

    2013-10-01

    Unlike the majority of actinomycete secondary metabolic pathways, the biosynthesis of peptidoglycan glycosyltransferase inhibitor moenomycin in Streptomyces ghanaensis does not involve any cluster-situated regulators (CSRs). This raises questions about the regulatory signals that initiate and sustain moenomycin production. We now show that three pleiotropic regulatory genes for Streptomyces morphogenesis and antibiotic production-bldA, adpA and absB-exert multi-layered control over moenomycin biosynthesis in native and heterologous producers. The bldA gene for tRNA(Leu)UAA is required for the translation of rare UUA codons within two key moenomycin biosynthetic genes (moe), moeO5 and moeE5. It also indirectly influences moenomycin production by controlling the translation of the UUA-containing adpA and, probably, other as-yet-unknown repressor gene(s). AdpA binds key moe promoters and activates them. Furthermore, AdpA interacts with the bldA promoter, thus impacting translation of bldA-dependent mRNAs-that of adpA and several moe genes. Both adpA expression and moenomycin production are increased in an absB-deficient background, most probably because AbsB normally limits adpA mRNA abundance through ribonucleolytic cleavage. Our work highlights an underappreciated strategy for secondary metabolism regulation, in which the interaction between structural genes and pleiotropic regulators is not mediated by CSRs. This strategy might be relevant for a growing number of CSR-free gene clusters unearthed during actinomycete genome mining. PMID:24153004

  9. Heterologous Production of the Marine Myxobacterial Antibiotic Haliangicin and Its Unnatural Analogues Generated by Engineering of the Biochemical Pathway.

    PubMed

    Sun, Yuwei; Feng, Zhiyang; Tomura, Tomohiko; Suzuki, Akira; Miyano, Seishi; Tsuge, Takashi; Mori, Hitoshi; Suh, Joo-Won; Iizuka, Takashi; Fudou, Ryosuke; Ojika, Makoto

    2016-01-01

    Despite their fastidious nature, marine myxobacteria have considerable genetic potential to produce novel secondary metabolites. The marine myxobacterium Haliangium ochraceum SMP-2 produces the antifungal polyketide haliangicin (1), but its productivity is unsatisfactory. The biosynthetic gene cluster hli (47.8 kbp) associated with 1 was identified and heterologously expressed in Myxococcus xanthus to permit the production of 1 with high efficiency (tenfold greater amount and threefold faster in growth speed compared with the original producer), as well as the generation of bioactive unnatural analogues of 1 through gene manipulation. A unique acyl-CoA dehydrogenase was found to catalyse an unusual γ,δ-dehydrogenation of the diketide starter unit, leading to the formation of the terminal alkene moiety of 1. Biological evaluation of the analogues obtained through this study revealed that their bioactivities (anti-oomycete and cytotoxic activities) can be modified by manipulating the vinyl epoxide at the terminus opposite the β-methoxyacrylate pharmacophore. PMID:26915413

  10. Heterologous Production of the Marine Myxobacterial Antibiotic Haliangicin and Its Unnatural Analogues Generated by Engineering of the Biochemical Pathway

    PubMed Central

    Sun, Yuwei; Feng, Zhiyang; Tomura, Tomohiko; Suzuki, Akira; Miyano, Seishi; Tsuge, Takashi; Mori, Hitoshi; Suh, Joo-Won; Iizuka, Takashi; Fudou, Ryosuke; Ojika, Makoto

    2016-01-01

    Despite their fastidious nature, marine myxobacteria have considerable genetic potential to produce novel secondary metabolites. The marine myxobacterium Haliangium ochraceum SMP-2 produces the antifungal polyketide haliangicin (1), but its productivity is unsatisfactory. The biosynthetic gene cluster hli (47.8 kbp) associated with 1 was identified and heterologously expressed in Myxococcus xanthus to permit the production of 1 with high efficiency (tenfold greater amount and threefold faster in growth speed compared with the original producer), as well as the generation of bioactive unnatural analogues of 1 through gene manipulation. A unique acyl-CoA dehydrogenase was found to catalyse an unusual γ,δ-dehydrogenation of the diketide starter unit, leading to the formation of the terminal alkene moiety of 1. Biological evaluation of the analogues obtained through this study revealed that their bioactivities (anti-oomycete and cytotoxic activities) can be modified by manipulating the vinyl epoxide at the terminus opposite the β-methoxyacrylate pharmacophore. PMID:26915413

  11. Antibiotics and Resistance: Glossary

    MedlinePlus

    ... induced by natural or human activity on the ecology and living organisms. Ecology The study of the relationships and interactions between ... antibiotics The Cost of Resistance Science of Resistance Ecology Antibiotics in Agriculture Antibacterial Agents Glossary References Web ...

  12. MedlinePlus: Antibiotics

    MedlinePlus

    ... or not using them properly, can add to antibiotic resistance . This happens when bacteria change and become able ... ports Pseudomembranous colitis Sensitivity analysis Related Health Topics Antibiotic Resistance Bacterial Infections Medicines National Institutes of Health The ...

  13. Antibiotic-associated encephalopathy.

    PubMed

    Bhattacharyya, Shamik; Darby, R Ryan; Raibagkar, Pooja; Gonzalez Castro, L Nicolas; Berkowitz, Aaron L

    2016-03-01

    Delirium is a common and costly complication of hospitalization. Although medications are a known cause of delirium, antibiotics are an underrecognized class of medications associated with delirium. In this article, we comprehensively review the clinical, radiologic, and electrophysiologic features of antibiotic-associated encephalopathy (AAE). AAE can be divided into 3 unique clinical phenotypes: encephalopathy commonly accompanied by seizures or myoclonus arising within days after antibiotic administration (caused by cephalosporins and penicillin); encephalopathy characterized by psychosis arising within days of antibiotic administration (caused by quinolones, macrolides, and procaine penicillin); and encephalopathy accompanied by cerebellar signs and MRI abnormalities emerging weeks after initiation of antibiotics (caused by metronidazole). We correlate these 3 clinical phenotypes with underlying pathophysiologic mechanisms of antibiotic neurotoxicity. Familiarity with these types of antibiotic toxicity can improve timely diagnosis of AAE and prompt antibiotic discontinuation, reducing the time patients spend in the delirious state. PMID:26888997

  14. Combating Antibiotic Resistance

    MedlinePlus

    ... for infectious diseases. back to top Antibiotics Fight Bacteria, Not Viruses Antibiotics are meant to be used ... treat strep throat, which is caused by streptococcal bacteria, and skin infections caused by staphylococcal bacteria. Although ...

  15. Improvement of the enediyne antitumor antibiotic C-1027 production by manipulating its biosynthetic pathway regulation in Streptomyces globisporus.

    PubMed

    Chen, Yihua; Yin, Min; Horsman, Geoff P; Shen, Ben

    2011-03-25

    The production of C-1027 in Streptomyces globisporus was previously increased 2- to 3-fold by manipulating three pathway-specific activators, SgcR1, SgcR2, and SgcR3. In this study, we have further characterized two putative C-1027 regulatory genes, sgcE1 and sgcR, by in vivo inactivation. The HxlR family DNA-binding protein SgcE1 was not essential for C-1027 biosynthesis, since inactivation of sgcE1 showed no effect on C-1027 production. In contrast, the proposed repressive role of the sgcR gene was confirmed by a 3-fold increase in C-1027 production in the ΔsgcR mutant S. globisporus SB1022 strain relative to the wild-type strain. Considering SgcR shows no significant similarity to any protein of known function, it may be representative of a new family of regulatory proteins. Finally, overexpression of the previously characterized activator sgcR1 in S. globisporus SB1022 increased the C-1027 yield to 37.5 ± 7.7 mg/L, which is about 7-fold higher than the wild-type strain. PMID:21250756

  16. Fungal Biotransformation of Tetracycline Antibiotics.

    PubMed

    Shang, Zhuo; Salim, Angela A; Khalil, Zeinab; Bernhardt, Paul V; Capon, Robert J

    2016-08-01

    The commercial antibiotics tetracycline (3), minocycline (4), chlortetracycline (5), oxytetracycline (6), and doxycycline (7) were biotransformed by a marine-derived fungus Paecilomyces sp. to yield seco-cyclines A-H (9-14, 18 and 19) and hemi-cyclines A-E (20-24). Structures were assigned by detailed spectroscopic analysis, and in the case of 10 X-ray crystallography. Parallel mechanisms account for substrate-product specificity, where 3-5 yield seco-cyclines and 6 and 7 yield hemi-cyclines. The susceptibility of 3-7 to fungal biotransformation is indicative of an unexpected potential for tetracycline "degradation" (i.e., antibiotic resistance) in fungal genomes. Significantly, the fungal-derived tetracycline-like viridicatumtoxins are resistant to fungal biotransformation, providing chemical insights that could inform the development of new tetracycline antibiotics resistant to enzymatic degradation. PMID:27419475

  17. Assessment of Bacterial Antibiotic Resistance Transfer in the Gut

    PubMed Central

    Schjørring, Susanne; Krogfelt, Karen A.

    2011-01-01

    We assessed horizontal gene transfer between bacteria in the gastrointestinal (GI) tract. During the last decades, the emergence of antibiotic resistant strains and treatment failures of bacterial infections have increased the public awareness of antibiotic usage. The use of broad spectrum antibiotics creates a selective pressure on the bacterial flora, thus increasing the emergence of multiresistant bacteria, which results in a vicious circle of treatments and emergence of new antibiotic resistant bacteria. The human gastrointestinal tract is a massive reservoir of bacteria with a potential for both receiving and transferring antibiotic resistance genes. The increased use of fermented food products and probiotics, as food supplements and health promoting products containing massive amounts of bacteria acting as either donors and/or recipients of antibiotic resistance genes in the human GI tract, also contributes to the emergence of antibiotic resistant strains. This paper deals with the assessment of antibiotic resistance gene transfer occurring in the gut. PMID:21318188

  18. Killing of Mycolic Acid-Containing Bacteria Aborted Induction of Antibiotic Production by Streptomyces in Combined-Culture.

    PubMed

    Asamizu, Shumpei; Ozaki, Taro; Teramoto, Kanae; Satoh, Katsuya; Onaka, Hiroyasu

    2015-01-01

    Co-culture of Streptomyces with mycolic acid-containing bacteria (MACB), which we termed "combined-culture," alters the secondary metabolism pattern in Streptomyces and has been a useful method for the discovery of bioactive natural products. In the course of our investigation to identify the inducing factor(s) of MACB, we previously observed that production of pigments in Streptomyces lividans was not induced by factors such as culture extracts or mycolic acids. Although dynamic changes occurred in culture conditions because of MACB, the activation of pigment production by S. lividans was observed in a limited area where both colonies were in direct contact. This suggested that direct attachment of cells is a requirement and that components on the MACB cell membrane may play an important role in the response by S. lividans. Here we examined whether this response was influenced by dead MACB that possess intact mycolic acids assembled on the outer cell membrane. Formaldehyde fixation and γ-irradiation were used to prepare dead cells that retain their shape and mycolic acids of three MACB species: Tsukamurella pulmonis, Rhodococcus erythropolis, and Rhodococcus opacus. Culturing tests verified that S. lividans does not respond to the intact dead cells of three MACB. Observation of combined-culture by scanning electron microscopy (SEM) indicated that adhesion of live MACB to S. lividans mycelia were a significant interaction that resulted in formation of co-aggregation. In contrast, in the SEM analysis, dead cells were not observed to adhere. Therefore, direct attachment by live MACB cells is proposed as one of the possible factors that causes Streptomyces to alter its specialized metabolism in combined-culture. PMID:26544713

  19. Killing of Mycolic Acid-Containing Bacteria Aborted Induction of Antibiotic Production by Streptomyces in Combined-Culture

    PubMed Central

    Asamizu, Shumpei; Ozaki, Taro; Teramoto, Kanae; Satoh, Katsuya; Onaka, Hiroyasu

    2015-01-01

    Co-culture of Streptomyces with mycolic acid-containing bacteria (MACB), which we termed “combined-culture,” alters the secondary metabolism pattern in Streptomyces and has been a useful method for the discovery of bioactive natural products. In the course of our investigation to identify the inducing factor(s) of MACB, we previously observed that production of pigments in Streptomyces lividans was not induced by factors such as culture extracts or mycolic acids. Although dynamic changes occurred in culture conditions because of MACB, the activation of pigment production by S. lividans was observed in a limited area where both colonies were in direct contact. This suggested that direct attachment of cells is a requirement and that components on the MACB cell membrane may play an important role in the response by S. lividans. Here we examined whether this response was influenced by dead MACB that possess intact mycolic acids assembled on the outer cell membrane. Formaldehyde fixation and γ-irradiation were used to prepare dead cells that retain their shape and mycolic acids of three MACB species: Tsukamurella pulmonis, Rhodococcus erythropolis, and Rhodococcus opacus. Culturing tests verified that S. lividans does not respond to the intact dead cells of three MACB. Observation of combined-culture by scanning electron microscopy (SEM) indicated that adhesion of live MACB to S. lividans mycelia were a significant interaction that resulted in formation of co-aggregation. In contrast, in the SEM analysis, dead cells were not observed to adhere. Therefore, direct attachment by live MACB cells is proposed as one of the possible factors that causes Streptomyces to alter its specialized metabolism in combined-culture. PMID:26544713

  20. Reconnaissance data for glyphosate, other selected herbicides, their degradation products, and antibiotics in 51 streams in nine midwestern states, 2002

    USGS Publications Warehouse

    Scribner, Elisabeth A.; Battaglin, William A.; Dietze, Julie E.; Thurman, E.M.

    2003-01-01

    Since 1989, the U.S. Geological Survey has conducted periodic reconnaissance studies of streams in the Midwestern United States to determine the geographic and seasonal distribution of herbicide compounds. These studies have documented that large amounts of acetochlor, alachlor, atrazine, cyanazine, metolachlor, and their degradation products are flushed into streams during post-application runoff. Additional studies show that peak herbicide concentrations tend to occur during the first runoff after herbicide application and that herbicide flushes can occur during runoff for several weeks to months following application. Since the first stream study conducted in 1989, several significant changes in herbicide use have occurred. The most substantial change is the tripling in the use of glyphosate during the past 5 years. Over this same time period (1997-2001), usage of acetochlor and atrazine increased slightly, whereas alachlor, cyanazine, and metolachlor usage decreased. During 2002, 154 samples were collected from 51 streams in nine Midwestern States during three periods of runoff. This report provides a compilation of the analytical results of five laboratory methods. Results show that glyphosate was detected in 55 (36 percent) of the samples, and aminomethylphosphonic acid (a degradation product of glyphosate) was detected in 107 (69 percent) of the samples. Atrazine, the most frequently detected herbicide, was found in 93 percent of the samples, followed by metolachlor, found in 73 percent of the samples; metolachlor ethanesulfonic acid (ESA) and oxanilic acid (OXA) were the most frequently detected herbicide degradation products, both being found in more than 95 percent of the samples. The data presented here are valuable for comparison with results from the earlier reconnaissance studies.

  1. Use of organic acids and competitive exclusion product as an alternative to antibiotic as a growth promoter in the raising of commercial turkeys.

    PubMed

    Milbradt, E L; Okamoto, A S; Rodrigues, J C Z; Garcia, E A; Sanfelice, C; Centenaro, L P; Andreatti Filho, R L

    2014-07-01

    A study was conducted to investigate the effects of organic acids (OA) and competitive exclusion product (CE) on growth performance, intestinal morphology, and concentration of volatile fatty acids in the cecal content. The experiment lasted for 10 wk. Four hundred twenty 1-d-old female commercial cross turkey poults (British United Turkeys, BUT Big 9) were distributed into 4 treatments with 5 replicates/pen of 21 birds each. The birds were fed a basal diet without growth promoter (control), diet with lincomycin (44 mg/kg), diet with organic acids (2 g/kg), and diet with product of CE (10(9) cfu/kg). Dietary levels of other nutrients, housing, and general management practices were similar for all treatments. On the first week (d 0-7), the BW and BW gain of the birds that fed diets with OA were lower than in the control group. In the fattening phase (d 28-70), the feed intake of the OA-treated group was lower than compared with the control. The birds that received diet with OA and CE product presented higher concentrations of propionic acid, at 14 d, and butyric acid in cecal content at 28, 56, and 70 d, compared with the control. Dietary inclusion of additives had no significant effects on intestinal villus height, crypt depth, and villus:crypt ratio. Organic acids had negative effects either on early gain or feed intake throughout the study. Because the test was conducted under controlled experimental conditions, the additives that showed results similar to those found by using antibiotics should be studied further in commercial farms to obtain results that can be incorporated into practice. PMID:24812241

  2. New hydrolysis products of the beta-lactam antibiotic amoxicillin, their pH-dependent formation and search in municipal wastewater.

    PubMed

    Hirte, Kristin; Seiwert, Bettina; Schüürmann, Gerrit; Reemtsma, Thorsten

    2016-01-01

    Amoxicillin (AMX) is a widespread β-lactam-antibiotic and, together with some of its transformation products (TPs) originating from hydrolysis, a known environmental contaminant. To shed light on the abiotic degradation of AMX and the stability of its known TPs, laboratory hydrolysis experiments of AMX were carried out at pH 3, 7 and 11. Not only the rate of hydrolysis but also the pattern of TPs was strongly pH-dependent. The time courses of the obtained transformation products were analyzed by UPLC-HR-QToF-MS. AMX penicilloic acid (TP 1), AMX 2',5'-diketopiperazine (TP 2), AMX penilloic acid (TP 3) and 3-(4-hydroxyphenyl)pyrazinol (TP 4) were found at neutral pH. Surprisingly, the first three were not stable but transformed into 23 yet unknown TPs within three to four weeks. Seven TPs were tentatively identified, based on their product ion spectra and, where possible, confirmed with reference standards, e.g. penicillamine disulfide, 2-[amino(carboxy)methyl]-5,5-dimethyl-1,3-thiazolidine-4-carboxylic acid and dehydrocarboxylated amoxicillin penilloic acid. Analysis of samples from municipal wastewater treatment plants confirmed these findings with TP 1 being the dominant TP in the influent and a shift towards TP 2, TP 3 and TP 4 in the effluents. The lab experiments predicted up to 13 consecutive TPs from TP 1, TP 2 and TP 3 under neutral conditions. Their detection from surface waters will be difficult, because their large number and slow formation kinetics will lead to comparatively low environmental concentrations. Nevertheless the abiotic degradation of TP 1, TP 2 and TP 3 to further TPs needs to be considered in future studies of the environmental fate of amoxicillin. PMID:26613181

  3. Prevalence and antibiotic resistance pattern of Salmonella serovars in integrated crop-livestock farms and their products sold in local markets.

    PubMed

    Peng, Mengfei; Salaheen, Serajus; Almario, Jose Alejandro; Tesfaye, Bezait; Buchanan, Robert; Biswas, Debabrata

    2016-05-01

    Major concern in the Mixed Crop-Livestock (MCL) farms, in which livestock and vegetables grown closely in the same facility, is cross-contamination of zoonotic bacterial pathogens especially Salmonella. To investigate the distribution of Salmonella serovars in MCL and their products, a total of 1287 pre-harvest samples from various farms and 1377 post-harvest samples from retail supermarkets in Maryland and Washington D.C. areas were collected and analysed. A total of 315 Salmonella isolates were recovered, with 17.44% and 5.88%, from MCL and conventional farms samples (P < 0.001). At post-harvest level, the prevalence of Salmonella was 30.95%, 19.83%, and 8.38% in chicken meat (P < 0.001) from farmers, organic, and conventional retail markets respectively, and 16.81% and 6.06% in produce products (P < 0.001) from farmers and organic retail markets, but none from conventional retail markets. From the isolated Salmonella, 34.50% was confirmed S. Typhimurium, followed by S. Heidelberg (10.86%) and S. Enteritidis (9.90%). The overall multi-antibiotic resistance in recovered Salmonella was 23.81% versus 4.55% in conventional and MCL farms (P = 0.004) and 66.67% versus 7.76% in conventional and farmers markets (P < 0.001). Overall the data reveals higher Salmonella risks in MCL farms' environment and their products sold in farmers markets and warrants taking necessary measures to limit Salmonella transmission. PMID:26914740

  4. An influence of the copy number of biosynthetic gene clusters on the production level of antibiotics in a heterologous host.

    PubMed

    Manderscheid, Niko; Bilyk, Bohdan; Busche, Tobias; Kalinowski, Jörn; Paululat, Thomas; Bechthold, Andreas; Petzke, Lutz; Luzhetskyy, Andriy

    2016-08-20

    Streptomyces albus J1074 is a well-known host for heterologous expression of secondary metabolites. To further increase its potential and to study the influence of cluster multiplication, additional φC31-attachment site was integrated into its genome using a system for transposon mutagenesis. Four secondary metabolite clusters were expressed in strains with different numbers of attachment sites, ranging from one to three copies of the site. Secondary metabolite production was examined and a new compound could be detected, purified and its structure was elucidated. PMID:27264245

  5. Antibiotic Resistance Questions and Answers

    MedlinePlus

    ... on the Farm Get Smart About Antibiotics Week Antibiotic Resistance Questions and Answers Language: English Español (Spanish) Recommend ... Many ear infections Top of Page Questions about Antibiotic Resistance Examples of How Antibiotic Resistance Spreads Click for ...

  6. The influence of antibiotic production and pre-emptive colonization on the population dynamics of Pantoea agglomerans (Erwinia herbicola) Eh1087 and Erwinia amylovora in planta.

    PubMed

    Giddens, Stephen R; Houliston, Gary J; Mahanty, H Khris

    2003-10-01

    Stigma colonization by Erwinia amylovora is the crucial first step in the development of most fire blight infections in apple and pear trees. Suppression at this point of the disease process by antagonists of E. amylovora, such as Pantoea agglomerans (Erwinia herbicola) strain Eh1087, is a rational approach to control fire blight. We tested the hypothesis that the ability of E. amylovora to compete with Eh1087 for colonization of a stigma is reduced by the potential for Eh1087 to produce the phenazine antibiotic, d-alanylgriseoluteic acid (AGA). In competition experiments on the stigmas of apple flowers, E. amylovora was significantly less successful against Eh1087 (AGA+) than against EhDeltaAGA (AGA-). Further experiments to test the importance of pre-emptive colonization of the stigma by either the pathogen or the antagonist suggested that AGA production significantly enhanced the competitiveness of Eh1087 when it was applied at the same time or 24 h before the pathogen. We also found that pre-emptive stigma colonization by either the pathogen or the antagonist resulted in a population that was resilient to subsequent invasion by a second species suggesting that niche exclusion has a dominant influence on the dynamics of bacterial populations on stigmas. PMID:14510856

  7. Marine Myxobacteria as a Source of Antibiotics—Comparison of Physiology, Polyketide-Type Genes and Antibiotic Production of Three New Isolates of Enhygromyxa salina

    PubMed Central

    Schäberle, Till F.; Goralski, Emilie; Neu, Edith; Erol, Özlem; Hölzl, Georg; Dörmann, Peter; Bierbaum, Gabriele; König, Gabriele M.

    2010-01-01

    Three myxobacterial strains, designated SWB004, SWB005 and SWB006, were obtained from beach sand samples from the Pacific Ocean and the North Sea. The strains were cultivated in salt water containing media and subjected to studies to determine their taxonomic status, the presence of genes for the biosynthesis of polyketides and antibiotic production. 16S rDNA sequence analysis revealed the type strain Enhygromyxa salina SHK-1T as their closest homolog, displaying between 98% (SWB005) and 99% (SWB004 and SWB006) sequence similarity. All isolates were rod-shaped cells showing gliding motility and fruiting body formation as is known for myxobacteria. They required NaCl for growth, with an optimum concentration of around 2% [w/v]. The G + C-content of genomic DNA ranged from 63.0 to 67.3 mol%. Further, the strains were analyzed for their potential to produce polyketide-type structures. PCR amplified ketosynthase-like gene fragments from all three isolates enhances the assumption that these bacteria produce polyketides. SWB005 was shown to produce metabolites with prominent antibacterial activity, including activity towards methicillin resistant Staphylococcus aureus (MRSA) and Staphylococcus epidermidis (MRSE). PMID:20948900

  8. Molecular and Functional Analyses of the Gene (eshA) Encoding the 52-Kilodalton Protein of Streptomyces coelicolor A3(2) Required for Antibiotic Production

    PubMed Central

    Kawamoto, Shinichi; Watanabe, Masakatsu; Saito, Natsumi; Hesketh, Andrew; Vachalova, Katerina; Matsubara, Keiko; Ochi, Kozo

    2001-01-01

    Analysis of proteins recovered in the S100 precipitate fraction of Streptomyces griseus after ultracentrifugation led to the identification of a 52-kDa protein which is produced during the late growth phase. The gene (eshA) which codes for this protein was cloned from S. griseus, and then its homologue was cloned from Streptomyces coelicolor A3(2). The protein was deduced to be 471 amino acids in length. The protein EshA is characterized by a central region that shows homology to the eukaryotic-type cyclic nucleotide-binding domains. Significant homology was also found to MMPI in Mycobacterium leprae, a major antigenic protein to humans. The eshA gene mapped near the chromosome end and was not essential for viability, as demonstrated by gene disruption experiments, but its disruption resulted in the abolishment of an antibiotic (actinorhodin but not undecylprodigiosin) production. Aerial mycelium was produced as abundantly as by the parent strain. Expression analysis of the EshA protein by Western blotting revealed that EshA is present only in late-growth-phase cells. The eshA gene was transcribed just preceding intracellular accumulation of the EshA protein, as determined by S1 nuclease protection, indicating that EshA expression is regulated at the transcription level. The expression of EshA was unaffected by introduction of the relA mutation, which blocks ppGpp synthesis. PMID:11567001

  9. Genetically Encoded Fragment-Based Discovery of Glycopeptide Ligands for Carbohydrate-Binding Proteins

    DOE PAGESBeta

    Ng, Simon; Lin, Edith; Kitov, Pavel I.; Tjhung, Katrina F.; Gerlits, Oksana O.; Deng, Lu; Kasper, Brian; Sood, Amika; Paschal, Beth M.; Zhang, Ping; et al

    2015-04-10

    Here we describe an approach to accelerate the search for competitive inhibitors for carbohydrate-recognition domains (CRDs). Genetically encoded fragment-based-discovery (GE-FBD) uses selection of phagedisplayed glycopeptides to dock a glycan fragment at the CRD and guide selection of Synergistic peptide motifs adjacent to the CRD. Starting from concanavalin A (ConA), a mannose (Man)-binding protein, as a bait, we narrowed a library of 108 glycopeptides to 86 leads that share a consensus motif, Man-WYD. Validation of synthetic leads yielded Man-WYDLF that exhibited 40 50-fold enhancement in affinity over methyl α-D-mannopyranoside (MeMan). Lectin array Suggested specificity: Man-WYD derivative bound only to 3 outmore » of 17 proteins-ConA, LcH, and PSA-that bind to Man. An X-ray structure of ConA.:Man-WYD proved that the trimannoside core and Man-WYD exhibit identical CRD docking; but their extra-CRD binding modes are significantly. different. Still, they have comparable affinity and selectivity for various Man-binding proteins. The intriguing observation provides new insight into functional mimicry :of carbohydrates by peptide ligands. GE-FBD may provide an alternative to rapidly search for competitive inhibitors for lectins.« less

  10. Genetically Encoded Fragment-Based Discovery of Glycopeptide Ligands for Carbohydrate-Binding Proteins

    SciTech Connect

    Ng, Simon; Lin, Edith; Kitov, Pavel I.; Tjhung, Katrina F.; Gerlits, Oksana O.; Deng, Lu; Kasper, Brian; Sood, Amika; Paschal, Beth M.; Zhang, Ping; Ling, Chang-Chun; Klassen, John S.; Noren, Christopher J.; Mahal, Lara K.; Woods, Robert J.; Coates, Leighton; Derda, Ratmir

    2015-04-10

    Here we describe an approach to accelerate the search for competitive inhibitors for carbohydrate-recognition domains (CRDs). Genetically encoded fragment-based-discovery (GE-FBD) uses selection of phagedisplayed glycopeptides to dock a glycan fragment at the CRD and guide selection of Synergistic peptide motifs adjacent to the CRD. Starting from concanavalin A (ConA), a mannose (Man)-binding protein, as a bait, we narrowed a library of 108 glycopeptides to 86 leads that share a consensus motif, Man-WYD. Validation of synthetic leads yielded Man-WYDLF that exhibited 40 50-fold enhancement in affinity over methyl α-D-mannopyranoside (MeMan). Lectin array Suggested specificity: Man-WYD derivative bound only to 3 out of 17 proteins-ConA, LcH, and PSA-that bind to Man. An X-ray structure of ConA.:Man-WYD proved that the trimannoside core and Man-WYD exhibit identical CRD docking; but their extra-CRD binding modes are significantly. different. Still, they have comparable affinity and selectivity for various Man-binding proteins. The intriguing observation provides new insight into functional mimicry :of carbohydrates by peptide ligands. GE-FBD may provide an alternative to rapidly search for competitive inhibitors for lectins.

  11. Conformational and dynamic properties of a 14 residue antifreeze glycopeptide from Antarctic cod.

    PubMed Central

    Lane, A. N.; Hays, L. M.; Feeney, R. E.; Crowe, L. M.; Crowe, J. H.

    1998-01-01

    The 1H and 13C NMR spectra of a 14-residue antifreeze glycopeptide from Antarctic cod (Tetramatomnus borchgrevinki) containing two proline residues have been assigned. 13C NMR relaxation experiments indicate motional anisotropy of the peptide, with a tumbling time in water at 5 degrees C of 3-4 ns. The relaxation data and lack of long-range NOEs are consistent with a linear peptide undergoing significant segmental motion. However, extreme values of some coupling constants and strong sequential NOEs indicate regions of local order, which are most evident at the two ATPA subsequences. Similar spectroscopic properties were observed in the 16-residue analogue containing an Arg-Ala dipeptide added to the C-terminus. Molecular modeling also showed no evidence of long-range order, but the two ATPA subsequences were relatively well determined by the experimental data. These motifs were quite distinct from helical structures or beta turns commonly found in proteins, but rather resemble sections of an extended polyproline helix. Thus, the NMR data provide a description of the local order, which is of relevance to the mechanism of action of the antifreeze activity of the antifreeze glycopeptides as well as their ability to protect cells during hypothermic storage. PMID:9684888

  12. Isolation and Characterization of Glycopeptide-Resistant Enterococci from Hospitalized Patients over a 30-Month Period

    PubMed Central

    Nelson, R. R. S.; McGregor, K. F.; Brown, A. R.; Amyes, S. G. B.; Young, H.-K.

    2000-01-01

    In February 1996, a Hospital Infection Control Practices Advisory Committee-style screening program was commenced to isolate and subsequently characterize glycopeptide-resistant enterococci (GRE) from patients at a hospital trust in Glasgow, Scotland. Over the next 30 months, GRE were isolated from 154 patients. GRE were isolated from patients in traditionally high-risk areas such as the renal unit and intensive care unit and also in areas considered to be lower risk, including medical wards and associated long-stay geriatric hospitals. The majority (90%) of isolates were Enterococcus faecium vanB. The remaining isolates consisted of seven E. faecalis (vanA), three E. gallinarum (vanC), and a further six E. faecium (five vanA, one both vanA and vanB) isolates. Analysis of SmaI-digested DNA by pulsed-field gel electrophoresis revealed that 34 of 40 (85%) VanB E. faecium isolates were identical or closely related, while 11 of 13 (85%) VanA GRE were distinct. High-level aminoglycoside resistance was seen in less than 8% of isolates. VanB E. faecium isolates were almost uniformly resistant to ampicillin and tetracycline. In this study, GRE have been isolated over a prolonged period from a broad range of patients. Glycopeptide resistance within the study hospital trust appeared to be mainly due to the clonal dissemination of a single strain of E. faecium VanB. PMID:10834962

  13. Hydrogen-bond interaction assisted branched copolymer HILIC material for separation and N-glycopeptides enrichment.

    PubMed

    Shao, Wenya; Liu, Jianxi; Yang, Kaiguang; Liang, Yu; Weng, Yejing; Li, Senwu; Liang, Zhen; Zhang, Lihua; Zhang, Yukui

    2016-09-01

    Hydrophilic interaction chromatography (HILIC) has attracted increasing attention in recent years due to its efficient application in the separation of polar compounds and the enrichment of glycopeptides. However, HILIC materials are still of weak hydrophilicity and thereby present weak retention and selectivity. In this work, branched copolymer modified hydrophilic material Sil@Poly(THMA-co-MBAAm), with high hydrophilicity and unique "claw-like" polyhydric groups, were prepared by "grafting from" thiol-ene click reaction. Due to the abundant functional groups provided by branched copolymer, the material showed excellent retention for nucleosides, necleobases, acidic compounds, sugars and peptides. Furthermore, Sil@Poly(THMA-co-MBAAm) was also applied for the N-glycosylation sites profiling towards the digests of the mouse brain, and 1997N-glycosylated peptides were identified, corresponding to 686 glycoprotein groups. Due to the assisted hydrogen-bond interaction, the selectivity for glycopeptide enrichment in the real sample reached 94.6%, which was the highest as far as we know. All these results indicated that such hydrogen-bond interaction assisted branched copolymer HILIC material possessed great potential for the separation and large scale glycoproteomics analysis. PMID:27343616

  14. Chemical Synthesis of a Glycopeptide Derived from Skp1 for Probing Protein Specific Glycosylation.

    PubMed

    Chinoy, Zoeisha S; Schafer, Christopher M; West, Christopher M; Boons, Geert-Jan

    2015-08-10

    Skp1 is a cytoplasmic and nuclear protein, best known as an adaptor of the SCF family of E3-ubiquitin ligases that label proteins for their degradation. Skp1 in Dictyostelium is posttranslationally modified on a specific hydroxyproline (Hyp) residue by a pentasaccharide, which consists of a Fucα1,2-Galβ-1,3-GlcNAcα core, decorated with two α-linked Gal residues. A glycopeptide derived form Skp1 was prepared to characterize the α-galactosyltransferase (AgtA) that mediates the addition of the α-Gal moieties, and to develop antibodies suitable for tracking the trisaccharide isoform of Skp1 in cells. A strategy was developed for the synthesis of the core trisaccharide-Hyp based on the use of 2-naphthylmethyl (Nap) ethers as permanent protecting groups to allow late stage installation of the Hyp moiety. Tuning of glycosyl donor and acceptor reactivities was critical for achieving high yields and anomeric selectivities of glycosylations. The trisaccharide-Hyp moiety was employed for the preparation of the glycopeptide using microwave-assisted solid phase peptide synthesis. Enzyme kinetic studies revealed that trisaccharide-Hyp and trisaccharide-peptide are poorly recognized by AgtA, indicating the importance of context provided by the native Skp1 protein for engagement with the active site. The trisaccharide-peptide was a potent immunogen capable of generating a rabbit antiserum that was highly selective toward the trisaccharide isoform of full-length Skp1. PMID:26179871

  15. Degradation Kinetics and Mechanism of a β-Lactam Antibiotic Intermediate, 6-Aminopenicillanic Acid, in a New Integrated Production Process.

    PubMed

    Su, Min; Sun, Hua; Zhao, Yingying; Lu, Aidang; Cao, Xiaohui; Wang, Jingkang

    2016-01-01

    In an effort to promote sustainability and to reduce manufacturing costs, the traditional production process for 6-aminopenicillanic acid (6-APA) has been modified to include less processing units. The objectives of this study are to investigate the degradation kinetics of 6-APA, to propose a reasonable degradation mechanism, and to optimize the manufacturing conditions within this new process. A series of degradation kinetic studies were conducted in the presence of impurities, as well as at various chemical and physical conditions. The concentrations of 6-APA were determined by high-performance liquid chromatography. An Arrhenius-type kinetic model was established to give a more accurate prediction on the degradation rates of 6-APA. A hydrolysis degradation mechanism is shown to be the major pathway for 6-APA. The degradation mechanisms and the kinetic models for 6-APA in the new system enable the design of a good manufacturing process with optimized parameters. PMID:26852849

  16. Fate and transport of antibiotic residues and antibiotic resistance genetic determinants during manure storage, treatment, and land application

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antibiotics are used in swine production for therapeutic treatment of disease and at sub-therapeutic levels for growth promotion and improvement of feed efficiency. It is estimated that ca.75% of antibiotics are not absorbed by animals and are excreted in waste. Antibiotic resistance selection occur...

  17. A facilely synthesized amino-functionalized metal-organic framework for highly specific and efficient enrichment of glycopeptides.

    PubMed

    Zhang, Yi-Wei; Li, Ze; Zhao, Qiang; Zhou, Ying-Lin; Liu, Hu-Wei; Zhang, Xin-Xiang

    2014-10-01

    A facilely synthesized amino-functionalized metal-organic framework (MOF) MIL-101(Cr)-NH2 was first applied for highly specific glycopeptide enrichment based on the hydrophilic interactions. With the special characteristics of the MOF, the material performed well in selectivity and sensitivity for both standard glycoprotein samples and complex biological samples. PMID:25131456

  18. New GO-PEI-Au-L-Cys ZIC-HILIC composites: synthesis and selective enrichment of glycopeptides.

    PubMed

    Jiang, Bo; Liang, Yu; Wu, Qi; Jiang, Hao; Yang, Kaiguang; Zhang, Lihua; Liang, Zhen; Peng, Xiaojun; Zhang, Yukui

    2014-06-01

    GO-PEI-Au-L-Cys composites were synthesized via loading gold nanoparticles on a GO surface using polyethylenimine as reducing and stabilizing reagents, followed by L-cysteine immobilization through an Au-S bond. The composites were applied as a kind of novel ZIC-HILIC material to achieve highly selective enrichment of glycopeptides from biological samples. PMID:24752239

  19. Unusual transglycosylation activity of Flavobacterium meningosepticum endoglycosidases enables convergent chemoenzymatic synthesis of core fucosylated complex N-glycopeptides

    PubMed Central

    Huang, Wei; Li, Jie

    2012-01-01

    Structurally well-defined, homogeneous glycopeptides and glycoproteins are indispensable tools for functional glycomics studies. By screening of various endo-β-N-acetylglucosaminidases using an appropriate synthetic donor and acceptor substrates, we have found that the Flavobacterium meningosepticum endo-β-N-acetylglucosaminidases glycosidases (GH family 18), including Endo-F2 and Endo-F3, were able to glycosylate α-1,6-fucosylated GlcNAc derivative to provide natural, core-fucosylated complex type N-glycopeptides. The Endo-F2 and Endo-F3 were efficient for transferring both sialylated and asialylated glycans and were highly specific for an α-1,6-fucosyllated GlcNAc-peptide as acceptor for transglycosylation, as they showed only marginal activity on non-fucosylated GlcNAc-peptide. In contrast, we found that the commonly used endoglycosidases such as Endo-A and Endo-M, which belong to GH family 85, were unable to take α-1,6-fucosyl-GlcNAc derivative as acceptor for transglycosylation. The novel activity of Endo-F2 and Endo-F3 was successfully applied for a highly convergent chemoenzymatic synthesis of a full-size CD52 glycopeptide antigen carrying both terminal sialic acid and core fucose. This is the first report on endoglycosidases that are able to glycosylate α-1,6-fucosylated GlcNAc derivatives to form natural core-fucosylated glycopeptides. PMID:21374780

  20. A Hybrid NRPS-PKS Gene Cluster Related to the Bleomycin Family of Antitumor Antibiotics in Alteromonas macleodii Strains

    PubMed Central

    Mizuno, Carolina Megumi; Kimes, Nikole E.; López-Pérez, Mario; Ausó, Eva; Rodriguez-Valera, Francisco; Ghai, Rohit

    2013-01-01

    Although numerous marine bacteria are known to produce antibiotics via hybrid NRPS-PKS gene clusters, none have been previously described in an Alteromonas species. In this study, we describe in detail a novel hybrid NRPS-PKS cluster identified in the plasmid of the Alteromonasmacleodii strain AltDE1 and analyze its relatedness to other similar gene clusters in a sequence-based characterization. This is a mobile cluster, flanked by transposase-like genes, that has even been found inserted into the chromosome of some Alteromonasmacleodii strains. The cluster contains separate genes for NRPS and PKS activity. The sole PKS gene appears to carry a novel acyltransferase domain, quite divergent from those currently characterized. The predicted specificities of the adenylation domains of the NRPS genes suggest that the final compound has a backbone very similar to bleomycin related compounds. However, the lack of genes involved in sugar biosynthesis indicates that the final product is not a glycopeptide. Even in the absence of these genes, the presence of the cluster appears to confer complete or partial resistance to phleomycin, which may be attributed to a bleomycin-resistance-like protein identified within the cluster. This also suggests that the compound still shares significant structural similarity to bleomycin. Moreover, transcriptomic evidence indicates that the NRPS-PKS cluster is expressed. Such sequence-based approaches will be crucial to fully explore and analyze the diversity and potential of secondary metabolite production, especially from increasingly important sources like marine microbes. PMID:24069455

  1. Thiol-ene click synthesis of L-Cysteine-bonded zwitterionic hydrophilic magnetic nanoparticles for selective and efficient enrichment of glycopeptides.

    PubMed

    Wu, Runqing; Xie, Yang; Deng, Chunhui

    2016-11-01

    Efficient and specific enrichment of low-abundant glycopeptides from complex biological samples is essential to glycoproteomics analysis. Herein, novel magnetic zwitterionic hydrophilic nanoparticles based on thiol-ene click chemistry were synthesized. The functionalized magnetic nanoparticles exhibited superior performance in glycopeptide enrichment of HRP tryptic digest, demonstrating low detection limit (0.04ng/μL), high selectivity (a mixture of HRP and BSA at the mass ratio of 1:50) and reproducibility (5 repeating cycles). In addition, the material was successfully applied to glycopeptide enrichment from human serum. The outstanding results indicate the potential of the method in the development of glycoproteomics analysis in real biological samples. PMID:27591639

  2. Regulation of the AbrA1/A2 Two-Component System in Streptomyces coelicolor and the Potential of Its Deletion Strain as a Heterologous Host for Antibiotic Production

    PubMed Central

    Rico, Sergio; Yepes, Ana; Rodríguez, Héctor; Santamaría, Jorge; Antoraz, Sergio; Krause, Eva M.; Díaz, Margarita; Santamaría, Ramón I.

    2014-01-01

    The Two-Component System (TCS) AbrA1/A2 from Streptomyces coelicolor M145 is a negative regulator of antibiotic production and morphological differentiation. In this work we show that it is able to auto-regulate its expression, exerting a positive induction of its own operon promoter, and that its activation is dependent on the presence of iron. The overexpression of the abrA2 response regulator (RR) gene in the mutant ΔabrA1/A2 results in a toxic phenotype. The reason is an excess of phosphorylated AbrA2, as shown by phosphoablative and phosphomimetic AbrA2 mutants. Therefore, non-cognate histidine kinases (HKs) or small phospho-donors may be responsible for AbrA2 phosphorylation in vivo. The results suggest that in the parent strain S. coelicolor M145 the correct amount of phosphorylated AbrA2 is adjusted through the phosphorylation-dephosphorylation activity rate of the HK AbrA1. Furthermore, the ABC transporter system, which is part of the four-gene operon comprising AbrA1/A2, is necessary to de-repress antibiotic production in the TCS null mutant. Finally, in order to test the possible biotechnological applications of the ΔabrA1/A2 strain, we demonstrate that the production of the antitumoral antibiotic oviedomycin is duplicated in this strain as compared with the production obtained in the wild type, showing that this strain is a good host for heterologous antibiotic production. Thus, this genetically modified strain could be interesting for the biotechnology industry. PMID:25303210

  3. Effects of six antibiotics and their binary mixtures on growth of Pseudokirchneriella subcapitata.

    PubMed

    Magdaleno, A; Saenz, M E; Juárez, A B; Moretton, J

    2015-03-01

    The effect of ampicillin (AMP), amoxicillin (AMX), cephalotin (CEP), ciprofloxacin (CPF), gentamycin (GEN), and vancomycin (VAN) have been examined individually and as binary mixtures, on a non-target aquatic organism, the green alga Pseudokichneriella subcapitata. The β-lactam antibiotics AMP and AMX were not toxic to the alga at concentrations up to 2000 mgl(-1) (less than 10% of algal growth inhibition), whereas the fluoroquinolone CPF, and the aminoglycoside GEN were the most toxic antibiotics, with an EC50=11.3 ± 0.7 mgl(-1) and 19.2 ± 0.5 mgl(-1), respectively. The cephalosporin CEP and the glycopeptide VAN were less toxic than the last two mentioned, showing an EC50>600 mgl(-1) and 724 ± 20 mgl(-1), respectively. The toxicological interactions of binary mixtures were predicted by the two classical models of additivity: concentration addition (CA) and independent action (IA), and compared to the experimentally determined toxicities over a range of concentrations between 1 and 50 mgl(-1). In all cases a clear synergistic effect was observed, showing that single compound toxicity data are not adequate for the prediction of aquatic toxicities of antibiotic mixtures. Risk assessment was performed by calculating the ratio between predicted environmental concentrations (PEC) and the predicted no effect concentration (PNEC). All the antibiotics tested, excepting GEN, have a potential ecological risk, taking into account the PEC of hospital effluents from Buenos Aires, Argentina. These risks increase when antibiotics are present in binary mixtures. PMID:25483375

  4. Agricultural use of antibiotics and the evolution and transfer of antibiotic-resistant bacteria

    PubMed Central

    Khachatourians, G G

    1998-01-01

    Microbial Resistance to antibiotics is on the rise, in part because of inappropriate use of antibiotics in human medicine but also because of practices in the agricultural industry. Intensive animal production involves giving livestock animals large quantities of antibiotics to promote growth and prevent infection. These uses promote the selection of antibiotic resistance in bacterial populations. The resistant bacteria from agricultural environments may be transmitted to humans, in whom they cause disease that cannot be treated by conventional antibiotics. The author reviews trends in antibiotic use in animal husbandry and agriculture in general. The development of resistance is described, along with the genetic mechanisms that create resistance and facilitate its spread among bacterial species. Particular aspects of resistance in bacterial species common to both the human population and the agrifood industry are emphasized. Control measures that might reverse the current trends are highlighted. PMID:9835883

  5. Antibiotics From Microbes: Converging To Kill

    PubMed Central

    Fischbach, Michael A.

    2011-01-01

    Summary As genetically encoded small molecules, antibiotics are phenotypes that have resulted from mutation and natural selection. Advances in genetics, biochemistry, and bioinformatics have connected hundreds of antibiotics to the gene clusters that encode them, allowing these molecules to be analyzed using the tools of evolutionary biology. This review surveys examples of convergent evolution from microbially produced antibiotics, including the convergence of distinct gene clusters on similar phenotypes and the merger of distinct gene clusters into a single functional unit. Examining antibiotics through an evolutionary lens highlights the versatility of biosynthetic pathways, reveals lessons for combating antibiotic resistance, and provides an entry point for studying the natural roles of these natural products. PMID:19695947

  6. Molecular Regulation of Antibiotic Biosynthesis in Streptomyces

    PubMed Central

    Liu, Gang; Chandra, Govind; Niu, Guoqing

    2013-01-01

    SUMMARY Streptomycetes are the most abundant source of antibiotics. Typically, each species produces several antibiotics, with the profile being species specific. Streptomyces coelicolor, the model species, produces at least five different antibiotics. We review the regulation of antibiotic biosynthesis in S. coelicolor and other, nonmodel streptomycetes in the light of recent studies. The biosynthesis of each antibiotic is specified by a large gene cluster, usually including regulatory genes (cluster-situated regulators [CSRs]). These are the main point of connection with a plethora of generally conserved regulatory systems that monitor the organism's physiology, developmental state, population density, and environment to determine the onset and level of production of each antibiotic. Some CSRs may also be sensitive to the levels of different kinds of ligands, including products of the pathway itself, products of other antibiotic pathways in the same organism, and specialized regulatory small molecules such as gamma-butyrolactones. These interactions can result in self-reinforcing feed-forward circuitry and complex cross talk between pathways. The physiological signals and regulatory mechanisms may be of practical importance for the activation of the many cryptic secondary metabolic gene cluster pathways revealed by recent sequencing of numerous Streptomyces genomes. PMID:23471619

  7. New antibiotics for bad bugs: where are we?

    PubMed Central

    2013-01-01

    Bacterial resistance to antibiotics is growing up day by day in both community and hospital setting, with a significant impact on the mortality and morbidity rates and the financial burden that is associated. In the last two decades multi drug resistant microorganisms (both hospital- and community-acquired) challenged the scientific groups into developing new antimicrobial compounds that can provide safety in use according to the new regulation, good efficacy patterns, and low resistance profile. In this review we made an evaluation of present data regarding the new classes and the new molecules from already existing classes of antibiotics and the ongoing trends in antimicrobial development. Infectious Diseases Society of America (IDSA) supported a proGram, called “the ′10 × ´20′ initiative”, to develop ten new systemic antibacterial drugs within 2020. The microorganisms mainly involved in the resistance process, so called the ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumanii, Pseudomonas aeruginosa, and enterobacteriaceae) were the main targets. In the era of antimicrobial resistance the new antimicrobial agents like fifth generation cephalosporins, carbapenems, monobactams, β-lactamases inhibitors, aminoglycosides, quinolones, oxazolidones, glycopeptides, and tetracyclines active against Gram-positive pathogens, like vancomycin-resistant S. aureus (VRSA) and MRSA, penicillin-resistant streptococci, and vancomycin resistant Enterococcus (VRE) but also against highly resistant Gram-negative organisms are more than welcome. Of these compounds some are already approved by official agencies, some are still in study, but the need of new antibiotics still does not cover the increasing prevalence of antibiotic-resistant bacterial infections. Therefore the management of antimicrobial resistance should also include fostering coordinated actions by all stakeholders, creating policy guidance, support

  8. New antibiotics for bad bugs: where are we?

    PubMed

    Bassetti, Matteo; Merelli, Maria; Temperoni, Chiara; Astilean, Augusta

    2013-01-01

    Bacterial resistance to antibiotics is growing up day by day in both community and hospital setting, with a significant impact on the mortality and morbidity rates and the financial burden that is associated. In the last two decades multi drug resistant microorganisms (both hospital- and community-acquired) challenged the scientific groups into developing new antimicrobial compounds that can provide safety in use according to the new regulation, good efficacy patterns, and low resistance profile. In this review we made an evaluation of present data regarding the new classes and the new molecules from already existing classes of antibiotics and the ongoing trends in antimicrobial development. Infectious Diseases Society of America (IDSA) supported a proGram, called "the '10 × ´20' initiative", to develop ten new systemic antibacterial drugs within 2020. The microorganisms mainly involved in the resistance process, so called the ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumanii, Pseudomonas aeruginosa, and enterobacteriaceae) were the main targets. In the era of antimicrobial resistance the new antimicrobial agents like fifth generation cephalosporins, carbapenems, monobactams, β-lactamases inhibitors, aminoglycosides, quinolones, oxazolidones, glycopeptides, and tetracyclines active against Gram-positive pathogens, like vancomycin-resistant S. aureus (VRSA) and MRSA, penicillin-resistant streptococci, and vancomycin resistant Enterococcus (VRE) but also against highly resistant Gram-negative organisms are more than welcome. Of these compounds some are already approved by official agencies, some are still in study, but the need of new antibiotics still does not cover the increasing prevalence of antibiotic-resistant bacterial infections. Therefore the management of antimicrobial resistance should also include fostering coordinated actions by all stakeholders, creating policy guidance, support for

  9. [Micromonospora resistence to definite antibiotics and their ability to produce structurally analogous antibiotics].

    PubMed

    Bibikova, M V; Ivanitskaia, L P; Tikhonova, A S

    1980-01-01

    Thirty six cultures of Micromonospora freshly isolated from soil samples were studied with respect to their sensitivity to a number of antibiotics of various structures and modes of action. It was found that all of them were highly sensitive to penicillin, ristomycin, tetracycline, rifampicin, streptomycin, olivomycin, carminomycin and dactinomycin. Significant differences in sensitivity of the Micromonospora cultures were revealed only with respect to gentamicin, tobramicin, erythromycin and lincomycin. Seven cultures were resistant to gentamicin and tobramicin and sensitive to all of the other antibiotics. Broad spectrum antibiotics were isolated from these cultures. The study of the antibiotic chemistry showed that they were 2-desoxystreptamine-containing aminoglycosides. Two cultures proved to be resistant to erythromycin and lincomycin. When identified with the use of antibiotic resistant staphylococcal strains, the crude antibiotic substances isolated from these cultures appeared to be not active against staphylococci resistant to erythromycin and lincomycin. By their chromatograpi- behaviour the antibiotics were close to macrolides. Therefore, it was found that production of aminoglycoside and macrolide antibiotics was most characteristic of Micromonospora. A certain correlation between resistance of Micromonospora to these 2 antibiotic groups and capacity for their production was shown. PMID:7356302

  10. Cooperative Antibiotic Resistance in a Multi-Drug Environment

    NASA Astrophysics Data System (ADS)

    Yurtsev, Eugene; Dai, Lei; Gore, Jeff

    2013-03-01

    The emergence of antibiotic resistance in bacteria is a significant health concern. A frequent mechanism of antibiotic resistance involves the production of an enzyme which inactivates the antibiotic. By inactivating the antibiotic, resistant cells can ``share'' their resistance with other cells in the bacterial population, suggesting that it may be possible to observe cooperation between strains that inactivate different antibiotics. Here, we experimentally track the population dynamics of two E. coli strains in the presence of two different antibiotics. We find that together the strains are able to grow in antibiotic concentrations that inhibit growth of either of the strains individually. We observe that even when there is stable coexistence between the two strains, the population size of each strain can undergo large oscillations. We expect that our results will provide insight into the evolution of antibiotic resistance and the evolutionary origin of phenotypic diversity and cooperative behaviors.

  11. Antibiotics regulate the immune response in both presence and absence of lipopolysaccharide through modulation of Toll-like receptors, cytokine production and phagocytosis in vitro.

    PubMed

    Bode, Christian; Diedrich, Britta; Muenster, Stefan; Hentschel, Viktoria; Weisheit, Christina; Rommelsheim, Kuno; Hoeft, Andreas; Meyer, Rainer; Boehm, Olaf; Knuefermann, Pascal; Baumgarten, Georg

    2014-01-01

    The inflammatory response to pathogen-associated molecular patterns such as lipopolysaccharide (LPS) in sepsis is mediated via Toll-like receptors (TLRs). Since TLRs also trigger various immune functions, including phagocytosis, their modulation is a promising strategy in the treatment of sepsis. As antibiotics have immunomodulatory properties, this study examined the effect of commonly used classes of antibiotics on i) the expression of TLRs and cytokines and ii) the phagocytic activity under sepsis-like conditions in vitro. This was achieved by incubating THP-1 monocytes and peripheral blood mononuclear cells (PBMCs) obtained from patients after open-heart surgery with the addition of LPS and six key antibiotics (piperacillin, doxycycline, erythromycin, moxifloxacin or gentamicin). After 24h, mRNA levels of both cytokines (IL-1β, IL-6) and TLRs (1, 2, 4, and 6) were monitored and phagocytosis was determined following coincubation with Escherichia coli. Each antibiotic differentially regulated the gene expression of the investigated TLRs and cytokines in monocytes. Erythromycin, moxifloxacin and doxycyclin displayed the strongest effects and changed mRNA-levels of the investigated genes up to 5.6-fold. Consistent with this, antibiotics and, in particular, moxifloxacin, regulated the TLR-and cytokine expression in activated PBMCs obtained from patients after open-heart surgery. Furthermore, piperacillin, doxycyclin and moxifloxacin inhibited the phagocytic activity of monocytes. Our results suggest that antibiotics regulate the immune response by modulating TLR- and cytokine expression as well as phagocytosis under septic conditions. Moxifloxacin, doxycycline and erythromycin were shown to possess the strongest immunomodulatory effects and these antibiotic classes should be considered for future immunomodulatory studies in sepsis. PMID:24239744

  12. The two kinases, AbrC1 and AbrC2, of the atypical two-component system AbrC are needed to regulate antibiotic production and differentiation in Streptomyces coelicolor

    PubMed Central

    Rodríguez, Héctor; Rico, Sergio; Yepes, Ana; Franco-Echevarría, Elsa; Antoraz, Sergio; Santamaría, Ramón I.; Díaz, Margarita

    2015-01-01

    Two-component systems (TCSs) are the most important sensing mechanisms in bacteria. In Streptomyces, TCSs-mediated responses to environmental stimuli are involved in the regulation of antibiotic production. This study examines the individual role of two histidine kinases (HKs), AbrC1 and AbrC2, which form part of an atypical TCS in Streptomyces coelicolor. qRT-PCR analysis of the expression of both kinases demonstrated that both are expressed at similar levels in NB and NMMP media. Single deletion of abrC1 elicited a significant increase in antibiotic production, while deletion of abrC2 did not have any clear effect. The origin of this phenotype, probably related to the differential phosphorylation ability of the two kinases, was also explored indirectly, analyzing the toxic phenotypes associated with high levels of phosphorylated RR. The higher the AbrC3 regulator phosphorylation rate, the greater the cell toxicity. For the first time, the present work shows in Streptomyces the combined involvement of two different HKs in the response of a regulator to environmental signals. Regarding the possible applications of this research, the fact that an abrC1 deletion mutant overproduces three of the S. coelicolor antibiotics makes this strain an excellent candidate as a host for the heterologous production of secondary metabolites. PMID:26029189

  13. The two kinases, AbrC1 and AbrC2, of the atypical two-component system AbrC are needed to regulate antibiotic production and differentiation in Streptomyces coelicolor.

    PubMed

    Rodríguez, Héctor; Rico, Sergio; Yepes, Ana; Franco-Echevarría, Elsa; Antoraz, Sergio; Santamaría, Ramón I; Díaz, Margarita

    2015-01-01

    Two-component systems (TCSs) are the most important sensing mechanisms in bacteria. In Streptomyces, TCSs-mediated responses to environmental stimuli are involved in the regulation of antibiotic production. This study examines the individual role of two histidine kinases (HKs), AbrC1 and AbrC2, which form part of an atypical TCS in Streptomyces coelicolor. qRT-PCR analysis of the expression of both kinases demonstrated that both are expressed at similar levels in NB and NMMP media. Single deletion of abrC1 elicited a significant increase in antibiotic production, while deletion of abrC2 did not have any clear effect. The origin of this phenotype, probably related to the differential phosphorylation ability of the two kinases, was also explored indirectly, analyzing the toxic phenotypes associated with high levels of phosphorylated RR. The higher the AbrC3 regulator phosphorylation rate, the greater the cell toxicity. For the first time, the present work shows in Streptomyces the combined involvement of two different HKs in the response of a regulator to environmental signals. Regarding the possible applications of this research, the fact that an abrC1 deletion mutant overproduces three of the S. coelicolor antibiotics makes this strain an excellent candidate as a host for the heterologous production of secondary metabolites. PMID:26029189

  14. Antibiotic-induced diarrhea.

    PubMed

    Vogel, L C

    1995-01-01

    Diarrhea is a common complication of antibiotic therapy and can range from mild soiling of a cast to severe and life-threatening pseudomembranous colitis. Although clindamycin is the most notorious, almost all antibiotics, particularly penicillins and cephalosporins, may also be responsible (Bartlett, 1992; Kelly, Pothoulakis, & LaMont, 1994). Because of the frequent use of these antibiotics in orthopaedic patients, antibiotic-associated enteric disease is a common problem in this population. About 15% to 25% of cases of antibiotic-associated diarrhea are caused by Clostridium difficile (Bartlett, 1992; George, 1984; Kelly et al., 1994). The majority of patients with antibiotic-associated diarrhea have no identifiable etiologic agent. Salmonella, enterotoxin-producing Clostridium perfringens (Borriello et al., 1984) and Candida albicans (Danna et al., 1991) have rarely been identified as causative agents. This article describes the role of C. difficile as an enteric pathogen and its spectrum of clinical disease, including diagnosis, treatment, and prevention of nosocomial transmission. PMID:7761131

  15. Frontline antibiotic therapy.

    PubMed

    MacGowan, Alasdair; Albur, Maha

    2013-06-01

    The need to use front-line antibiotics wisely has never been greater. Antibiotic resistance and multi-drug resistant infection, driven by antibiotic use, remain major public health and professional concerns. To overcome these infection problems, use of older antibiotics active against multi drug-resistant pathogens is increasing - for example, colistin, fosfomycin, pivmecillinam, pristinamycin, temocillin and oral tetracyclines. The number of new antibacterials reaching clinical practice has reduced significantly in the last 20 years, most being focused on therapy of Gram-positive infection - eg linezolid, daptomycin, telavancin and ceftaroline. Recent guidance on antibiotic stewardship in NHS trusts in England is likely to provide a backdrop to antibiotic use in hospitals in the next 5 years. PMID:23760700

  16. Biotic acts of antibiotics

    PubMed Central

    Aminov, Rustam I.

    2013-01-01

    Biological functions of antibiotics are not limited to killing. The most likely function of antibiotics in natural microbial ecosystems is signaling. Does this signaling function of antibiotics also extend to the eukaryotic – in particular mammalian – cells? In this review, the host modulating properties of three classes of antibiotics (macrolides, tetracyclines, and β-lactams) will be briefly discussed. Antibiotics can be effective in treatment of a broad spectrum of diseases and pathological conditions other than those of infectious etiology and, in this capacity, may find widespread applications beyond the intended antimicrobial use. This use, however, should not compromise the primary function antibiotics are used for. The biological background for this inter-kingdom signaling is also discussed. PMID:23966991

  17. [Rational use of antibiotics].

    PubMed

    Walger, P

    2016-06-01

    International and national campaigns draw attention worldwide to the rational use of the available antibiotics. This has been stimulated by the high prevalence rates of drug-resistant pathogens, such as methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE), a threatening spread of development of resistance in Gram-negative rod-shaped bacteria and the selection of Clostridium difficile with a simultaneous clear reduction in the development of new antibiotics. The implementation of antibiotic stewardship programs aims to maintain their effectiveness by a rational use of the available antibiotics. The essential target of therapy with antibiotics is successful treatment of individual patients with bacterial infections. The optimal clinical treatment results can only be achieved when the toxicity, selection of pathogens and development of resistance are minimized. This article presents the principles of a rational antibiotic therapy. PMID:27246321

  18. Antibiotics and the burn patient.

    PubMed

    Ravat, François; Le-Floch, Ronan; Vinsonneau, Christophe; Ainaud, Pierre; Bertin-Maghit, Marc; Carsin, Hervé; Perro, Gérard

    2011-02-01

    Infection is a major problem in burn care and especially when it is due to bacteria with hospital-acquired multi-resistance to antibiotics. Moreover, when these bacteria are Gram-negative organisms, the most effective molecules are 20 years old and there is little hope of any new product available even in the distant future. Therefore, it is obvious that currently available antibiotics should not be misused. With this aim in mind, the following review was conducted by a group of experts from the French Society for Burn Injuries (SFETB). It examined key points addressing the management of antibiotics for burn patients: when to use or not, time of onset, bactericidia, combination, adaptation, de-escalation, treatment duration and regimen based on pharmacokinetic and pharmacodynamic characteristics of these compounds. The authors also considered antibioprophylaxis and some other key points such as: infection diagnosis criteria, bacterial inoculae and local treatment. French guidelines for the use of antibiotics in burn patients have been designed up from this work. PMID:20510518

  19. Metabolic products of microorganisms. 225. Elloramycin, a new anthracycline-like antibiotic from Streptomyces olivaceus. Isolation, characterization, structure and biological properties.

    PubMed

    Drautz, H; Reuschenbach, P; Zähner, H; Rohr, J; Zeeck, A

    1985-10-01

    Elloramycin (1), a new antibiotic produced by Streptomyces olivaceus strain Tü 2353, was detected by chemical screening. The dark yellow compound, molecular formula C32H36O15, is weakly active against a variety of Gram-positive bacteria, especially streptomycetes and against stem cells of L-1210 leukemia. Acidic hydrolysis of the antibiotic liberated elloramycinone (3) as aglycone and 2,3,4-tri-O-methyl-L-rhamnose, which was identified as methyl glycoside 5b. The structure of elloramycin was established by comparison of the spectra (UV, 1H NMR, 13C NMR) with those of the known tetracenomycin C (2), 3 and the fact that 2 and 3 gave the same tetramethyl ether after permethylation. Elloramycin is an anthracycline-like antibiotic, the aglycone resembles tetracenomycin C, the sugar is connected in a phenolic alpha-glycosidic linkage. PMID:3840789

  20. Enhanced immunogenicity of multivalent MUC1 glycopeptide antitumour vaccines based on hyperbranched polymers.

    PubMed

    Glaffig, M; Palitzsch, B; Stergiou, N; Schüll, C; Strassburger, D; Schmitt, E; Frey, H; Kunz, H

    2015-10-28

    Enhancing the immunogenicity of an antitumour vaccine still poses a major challenge. It depends upon the selected antigen and the mode of its presentation. We here describe a fully synthetic antitumour vaccine, which addresses both aspects. For the antigen, a tumour-associated MUC1 glycopeptide as B-cell epitope was synthesised and linked to the immunostimulating T-cell epitope P2 derived from tetanus toxoid. The MUC1-P2 conjugate is presented multivalently on a hyperbranched polyglycerol to the immune system. In comparison to a related vaccine of lower multivalency, this vaccine exposing more antigen structures on the hyperbranched polymer induced significantly stronger immune responses in mice and elicited IgG antibodies of distinctly higher affinity to epithelial tumour cells. PMID:26299280

  1. How Nature Morphs Peptide Scaffolds into Antibiotics

    PubMed Central

    Nolan, Elizabeth M.; Walsh, Christopher T.

    2010-01-01

    The conventional notion that peptides are poor candidates for orally available drugs because of protease-sensitive peptide bonds, intrinsic hydrophilicity, and ionic charges contrasts with the diversity of antibiotic natural products with peptide-based frameworks that are synthesized and utilized by Nature. Several of these antibiotics, including penicillin and vancomycin, are employed to treat bacterial infections in humans and have been best-selling therapeutics for decades. Others might provide new platforms for the design of novel therapeutics to combat emerging antibiotic-resistant bacterial pathogens. PMID:19058272

  2. Designing Safer and Greener Antibiotics

    PubMed Central

    Jordan, Andrew; Gathergood, Nicholas

    2013-01-01

    Since the production of the first pharmaceutically active molecules at the beginning of the 1900s, drug molecules and their metabolites have been observed in the environment in significant concentrations. In this review, the persistence of antibiotics in the environment and their associated effects on ecosystems, bacterial resistance and health effects will be examined. Solutions to these problems will also be discussed, including the pharmaceutical industries input, green chemistry, computer modeling and representative ionic liquid research. PMID:27029311

  3. The adjuvant activity of a non-toxic, water-soluble glycopeptide present in large quantities in the culture filtrate of Mycobacterium tuberculosis strain DT.

    PubMed Central

    Stewart-Tull, D E; Shimono, T; Kotani, S; Kato, M; Ogawa, Y; Yamamura, Y; Koga, T; Pearson, C M

    1975-01-01

    A water-soluble mycobacterial glycopeptide was obtained in large quantities from the culture supernatant fluid of M. tuberculosis strain DT. This glycopeptide was strongly adjuvant-active when injected, in a water-in-oil emulsion contianing ovalbumin, into guinea-pigs. In addition, it was devoid of cord factor toxicity in mice, polyarthritogenic activity in rats and cavity stimulating activity in rabbit lungs. Images FIG. 2 FIG. 3 FIG. 4 FIG. 5 FIG. 6 FIG. 8 PMID:806515

  4. Properties of a glycopeptide isolated from human Tamm-Horsfall glycoprotein. Interaction with leucoagglutinin and anti-(human Tamm-Horsfall glycoprotein) antibodies.

    PubMed Central

    Abbondanza, A; Franceschi, C; Licastro, F; Serafini-Cessi, F

    1980-01-01

    A sialylated glycopeptide isolated after Pronase digestion of human Tamm-Horsfall glycoprotein behaves as a powerful monovalent hapten in the precipitin reaction between human Tamm-Horsfall glycoprotein and leucoagglutinin, but fails to inhibit the interaction of the glycoprotein with rabbit anti-(human Tamm-Horsfall glycoprotein) antibodies. The glycopeptide is much less active than the intact glycoprotein as an inhibitor of lymphocyte transformation induced by leucoagglutinin. PMID:6967312

  5. Bioinspired Saccharide-Saccharide Interaction and Smart Polymer for Specific Enrichment of Sialylated Glycopeptides.

    PubMed

    Li, Xiuling; Xiong, Yuting; Qing, Guangyan; Jiang, Ge; Li, Xianqin; Sun, Taolei; Liang, Xinmiao

    2016-06-01

    Abnormal sialylation of proteins is highly associated with many major diseases, such as cancers and neurodegenerative diseases. However, this study is challenging owing to the difficulty in enriching trace sialylated glycopeptides (SGs) from highly complex biosamples. The key to solving this problem relies strongly on the design of novel SG receptors to capture the sialic acid (SA) moieties in a specific and tunable manner. Inspired by the saccharide-saccharide interactions in life systems, here we introduce saccharide-based SG receptors into this study. Allose (a monosaccharide) displays specific and pH-sensitive binding toward SAs. Integrating allose units into a polyacrylamide chain generates a saccharide-responsive smart copolymer (SRSC). Such design significantly improves the selectivity of SA binding; meanwhile, this binding can be intelligently triggered in a large extent by solution polarity and pH. As a result, SRSC exhibits high-performance enrichment capacity toward SGs, even under 500-fold interference of bovine serum albumins digests, which is notably higher than conventional materials. In real biosamples of HeLa cell lysates, 180 sialylated glycosylation sites (SGSs) have been identified using SRSC. This is apparently superior to those obtained by SA-binding lectins including WGA (18 SGSs) and SNA (22 SGSs). Furthermore, lactose displays good chemoselectivity toward diverse disaccharides, which indicated the good potential of lactose-based material in glycan discrimination. Subsequently, the lactose-based SRSC facilitates the stepwise isolation of O-linked or N-linked SGs with the same peptide sequence but varied glycans by CH3CN/H2O gradients. This study opens a new avenue for next generation of glycopeptide enrichment materials. PMID:27172767

  6. Bacteriocins – Exploring Alternatives to Antibiotics in Mastitis Treatment

    PubMed Central

    Pieterse, Reneé; Todorov, Svetoslav D.

    2010-01-01

    Mastitis is considered to be the most costly disease affecting the dairy industry. Management strategies involve the extensive use of antibiotics to treat and prevent this disease. Prophylactic dosages of antibiotics used in mastitis control programmes could select for strains with resistance to antibiotics. In addition, a strong drive towards reducing antibiotic residues in animal food products has lead to research in finding alternative antimicrobial agents. In this review we have focus on the pathogenesis of the mastitis in dairy cows, existing antibiotic treatments and possible alternative for application of bacteriocins from lactic acid bacteria in the treatment and prevention of this disease. PMID:24031528

  7. Anthracyclic products from Streptomyces erythromogenes nov. sp. Biotransformation of daunomycin (Dn) by an acellular preparation and synergism between Dn and some known antibiotics.

    PubMed

    Abdallah, N M; Devys, M; Barbier, M

    1982-01-01

    The filtrate broth as well as mycelium of the new strain Streptomyces erythrochromogenes nov. sp. isolated from Saudi Arabian soil, produce the antitumor antibiotic daunomycin 1 and two anthracyclic derivatives: 7-deoxy 13-dihydrodaunomycinone 2 and 7-deoxy daunomycinone 4. The biotransformation of 1 to 2 and 4 by an acellular enzyme preparation from the strain was found to be NADPH and/or NADH dependent. Mixtures of daunomycin 1 with chloramphenicol or penicillin showed superior antimicrobial activities against Bacillus subtilis ICC strain, than the individual antibiotics. PMID:7113265

  8. Identification and molecular phylogeny of coagulase-negative staphylococci isolates from Minas Frescal cheese in southeastern Brazil: Superantigenic toxin production and antibiotic resistance.

    PubMed

    Casaes Nunes, Raquel Soares; Pires de Souza, Camilla; Pereira, Karen Signori; Del Aguila, Eduardo Mere; Flosi Paschoalin, Vânia Margaret

    2016-04-01

    Minas Frescal is a typical Brazilian fresh cheese and one of the most popular dairy products in the country. This white soft, semiskimmed, nonripened cheese with high moisture content is obtained by enzymatic coagulation of cow milk using calf rennet or coagulants, usually in industrial dairy plants, but is also manufactured in small farms. Contamination of Minas Frescal by several staphylococci has been frequently reported. Coagulase-negative staphylococci (CNS) strains are maybe the most harmful, as they are able to produce heat-stable enterotoxins with super antigenic activities in food matrices, especially in dairy products such as soft cheeses. The aim of the present study was to investigate the presence of CNS strains in Minas Frescal marketed in southeastern Brazil concerning the risk of staphylococci food poisoning by the consumption of improperly manufactured cheese and the possibility of these food matrices being a reservoir of staphylococcal resistance to antimicrobials. Ten distinct CNS strains were found in 6 cheeses from distinct brands. The most frequent species were Staphylococcus saprophyticus (40%), Staphylococcus xylosus (30%), Staphylococcus sciuri (20%), and Staphylococcus piscifermentans (10%). Three strains were identified to the Staphylococcus genera. Three major species groups composed of 3 refined clusters were grouped by phylogenetic analyses with similarities over to 90%. All CNS strains carried multiple enterotoxin genes, with high incidence of sea and seb (90 and 70%, respectively), followed by sec/see, seh/sei, and sed with intermediate incidence (60, 50, and 40%, respectively), and, finally, seg/selk/selq/selr and selu with the lowest incidence (20 and 10%, respectively). Real-time reverse transcription PCR and ELISA assays confirmed the enteroxigenic character of the CNS strains, which expressed and produced the enterotoxins in vitro. The CNS strains showed multiresistance to antimicrobial agents such as β-lactams, vancomycin, and

  9. Prevalence of antibiotic-resistant E. coli in retail chicken: comparing conventional, organic, kosher, and raised without antibiotics

    PubMed Central

    Price, Lance B; Hungate, Bruce A

    2013-01-01

    Retail poultry products are known sources of antibiotic-resistant Escherichia coli, a major human health concern. Consumers have a range of choices for poultry, including conventional, organic, kosher, and raised without antibiotics (RWA) – designations that are perceived to indicate differences in quality and safety. However, whether these categories vary in the frequency of contamination with antibiotic-resistant E. coli is unknown. We examined the occurrence of antibiotic-resistant E. coli on raw chicken marketed as conventional, organic, kosher and RWA. From April – June 2012, we purchased 213 samples of raw chicken from 15 locations in the New York City metropolitan area. We screened E. coli isolates from each sample for resistance to 12 common antibiotics. Although the organic and RWA labels restrict the use of antibiotics, the frequency of antibiotic-resistant E. coli tended to be only slightly lower for RWA, and organic chicken was statistically indistinguishable from conventional products that have no restrictions. Kosher chicken had the highest frequency of antibiotic-resistant E. coli, nearly twice that of conventional products, a result that belies the historical roots of kosher as a means to ensure food safety. These results indicate that production methods influence the frequency of antibiotic-resistant E. coli on poultry products available to consumers. Future research to identify the specific practices that cause the high frequency of antibiotic-resistant E. coli in kosher chicken could promote efforts to reduce consumer exposure to this potential pathogen. PMID:24555073

  10. An accessible protocol for solid-phase extraction of N-linked glycopeptides through reductive amination by amine-functionalized magnetic nanoparticles.

    PubMed

    Zhang, Ying; Kuang, Min; Zhang, Lijuan; Yang, Pengyuan; Lu, Haojie

    2013-06-01

    In light of the significance of glycosylation for wealthy biological events, it is important to prefractionate glycoproteins/glycopeptides from complex biological samples. Herein, we reported a novel protocol of solid-phase extraction of glycopeptides through a reductive amination reaction by employing the easily accessible 3-aminopropyltriethoxysilane (APTES)-functionalized magnetic nanoparticles. The amino groups from APTES, which were assembled onto the surface of the nanoparticles through a one-step silanization reaction, could conjugate with the aldehydes from oxidized glycopeptides and, therefore, completed the extraction. To the best of our knowledge, this is the first example of applying the reductive amination reaction into the isolation of glycopeptides. Due to the elimination of the desalting step, the detection limit of glycopeptides was improved by 2 orders of magnitude, compared to the traditional hydrazide chemistry-based solid phase extraction, while the extraction time was shortened to 4 h, suggesting the high sensitivity, specificity, and efficiency for the extraction of N-linked glycopeptides by this method. In the meantime, high selectivity toward glycoproteins was also observed in the separation of Ribonuclease B from the mixtures contaminated with bovine serum albumin. What's more, this technique required significantly less sample volume, as demonstrated in the successful mapping of glycosylation of human colorectal cancer serum with the sample volume as little as 5 μL. Because of all these attractive features, we believe that the innovative protocol proposed here will shed new light on the research of glycosylation profiling. PMID:23659689

  11. Sublethal Concentrations of Antibiotics Cause Shift to Anaerobic Metabolism in Listeria monocytogenes and Induce Phenotypes Linked to Antibiotic Tolerance.

    PubMed

    Knudsen, Gitte M; Fromberg, Arvid; Ng, Yin; Gram, Lone

    2016-01-01

    The human pathogenic bacterium Listeria monocytogenes is exposed to antibiotics both during clinical treatment and in its saprophytic lifestyle. As one of the keys to successful treatment is continued antibiotic sensitivity, the purpose of this study was to determine if exposure to sublethal antibiotic concentrations would affect the bacterial physiology and induce antibiotic tolerance. Transcriptomic analyses demonstrated that each of the four antibiotics tested caused an antibiotic-specific gene expression pattern related to mode-of-action of the particular antibiotic. All four antibiotics caused the same changes in expression of several metabolic genes indicating a shift from aerobic to anaerobic metabolism and higher ethanol production. A mutant in the bifunctional acetaldehyde-CoA/alcohol dehydrogenase encoded by lmo1634 did not have altered antibiotic tolerance. However, a mutant in lmo1179 (eutE) encoding an aldehyde oxidoreductase where rerouting caused increased ethanol production was tolerant to three of four antibiotics tested. This shift in metabolism could be a survival strategy in response to antibiotics to avoid generation of ROS production from respiration by oxidation of NADH through ethanol production. The monocin locus encoding a cryptic prophage was induced by co-trimoxazole and repressed by ampicillin and gentamicin, and this correlated with an observed antibiotic-dependent biofilm formation. A monocin mutant (ΔlmaDCBA) had increased biofilm formation when exposed to increasing concentration of co-trimoxazole similar to the wild type, but was more tolerant to killing by co-trimoxazole and ampicillin. Thus, sublethal concentrations of antibiotics caused metabolic and physiological changes indicating that the organism is preparing to withstand lethal antibiotic concentrations. PMID:27462313

  12. Sublethal Concentrations of Antibiotics Cause Shift to Anaerobic Metabolism in Listeria monocytogenes and Induce Phenotypes Linked to Antibiotic Tolerance

    PubMed Central

    Knudsen, Gitte M.; Fromberg, Arvid; Ng, Yin; Gram, Lone

    2016-01-01

    The human pathogenic bacterium Listeria monocytogenes is exposed to antibiotics both during clinical treatment and in its saprophytic lifestyle. As one of the keys to successful treatment is continued antibiotic sensitivity, the purpose of this study was to determine if exposure to sublethal antibiotic concentrations would affect the bacterial physiology and induce antibiotic tolerance. Transcriptomic analyses demonstrated that each of the four antibiotics tested caused an antibiotic-specific gene expression pattern related to mode-of-action of the particular antibiotic. All four antibiotics caused the same changes in expression of several metabolic genes indicating a shift from aerobic to anaerobic metabolism and higher ethanol production. A mutant in the bifunctional acetaldehyde-CoA/alcohol dehydrogenase encoded by lmo1634 did not have altered antibiotic tolerance. However, a mutant in lmo1179 (eutE) encoding an aldehyde oxidoreductase where rerouting caused increased ethanol production was tolerant to three of four antibiotics tested. This shift in metabolism could be a survival strategy in response to antibiotics to avoid generation of ROS production from respiration by oxidation of NADH through ethanol production. The monocin locus encoding a cryptic prophage was induced by co-trimoxazole and repressed by ampicillin and gentamicin, and this correlated with an observed antibiotic-dependent biofilm formation. A monocin mutant (ΔlmaDCBA) had increased biofilm formation when exposed to increasing concentration of co-trimoxazole similar to the wild type, but was more tolerant to killing by co-trimoxazole and ampicillin. Thus, sublethal concentrations of antibiotics caused metabolic and physiological changes indicating that the organism is preparing to withstand lethal antibiotic concentrations. PMID:27462313

  13. Setamycin, a new antibiotic.

    PubMed

    Omura, S; Otoguro, K; Nishikiori, T; Oiwa, R; Iwai, Y

    1981-10-01

    A new antibiotic, setamycin, was extracted from the mycelia of a rare actinomycete strain KM-6054. The antibiotic, the molecular formula of which was found to be C42H61NO12 (tentative), is a yellow powder showing activity against some fungi, trichomonads and weakly against Gram-positive bacteria. PMID:7309621

  14. The future of antibiotics.

    PubMed

    Spellberg, Brad

    2014-01-01

    Antibiotic resistance continues to spread even as society is experiencing a market failure of new antibiotic research and development (R&D). Scientific, economic, and regulatory barriers all contribute to the antibiotic market failure. Scientific solutions to rekindle R&D include finding new screening strategies to identify novel antibiotic scaffolds and transforming the way we think about treating infections, such that the goal is to disarm the pathogen without killing it or modulate the host response to the organism without targeting the organism for destruction. Future economic strategies are likely to focus on 'push' incentives offered by public-private partnerships as well as increasing pricing by focusing development on areas of high unmet need. Such strategies can also help protect new antibiotics from overuse after marketing. Regulatory reform is needed to re-establish feasible and meaningful traditional antibiotic pathways, to create novel limited-use pathways that focus on highly resistant infections, and to harmonize regulatory standards across nations. We need new antibiotics with which to treat our patients. But we also need to protect those new antibiotics from misuse when they become available. If we want to break the cycle of resistance and change the current landscape, disruptive approaches that challenge long-standing dogma will be needed. PMID:25043962

  15. Antibiotic-Resistant Bacteria.

    ERIC Educational Resources Information Center

    Longenecker, Nevin E.; Oppenheimer, Dan

    1982-01-01

    A study conducted by high school advanced bacteriology students appears to confirm the hypothesis that the incremental administration of antibiotics on several species of bacteria (Escherichia coli, Staphylococcus epidermis, Bacillus sublitus, Bacillus megaterium) will allow for the development of antibiotic-resistant strains. (PEB)

  16. Antibiotic de-escalation.

    PubMed

    Masterton, Robert G

    2011-01-01

    Antibiotic de-escalation is a mechanism whereby the provision of effective initial antibiotic treatment is achieved while avoiding unnecessary antibiotic use that would promote the development of resistance. It is a key element within antimicrobial stewardship programs and treatment paradigms for serious sepsis. The embodiment of de-escalation is that based on microbiology results around the day 3 therapy point; the empiric antibiotic(s) that were started are stopped or reduced in number and/or narrowed in spectrum. Data are presented here which demonstrate that de-escalation is clinically effective and appropriate. However, the need for further studies, particularly in terms of realization of full benefits as well as implementation tools, is highlighted. De-escalation ought now to form a part of routine antimicrobial management, though how best to do it and the full breadth and scope of benefits remain to be identified. PMID:21144991

  17. Gut microbiota disturbance during antibiotic therapy

    PubMed Central

    Ferrer, Manuel; Martins dos Santos, Vitor AP; Ott, Stephan J; Moya, Andrés

    2014-01-01

    It is known that the gastrointestinal tract (GIT) microbiota responds to different antibiotics in different ways and that while some antibiotics do not induce disturbances of the community, others drastically influence the richness, diversity, and prevalence of bacterial taxa. However, the metabolic consequences thereof, independent of the degree of the community shifts, are not clearly understood. In a recent article, we used an integrative OMICS approach to provide new insights into the metabolic shifts caused by antibiotic disturbance. The study presented here further suggests that specific bacterial lineage blooms occurring at defined stages of antibiotic intervention are mostly associated with organisms that possess improved survival and colonization mechanisms, such as those of the Enterococcus, Blautia, Faecalibacterium, and Akkermansia genera. The study also provides an overview of the most variable metabolic functions affected as a consequence of a β-lactam antibiotic intervention. Thus, we observed that anabolic sugar metabolism, the production of acetyl donors and the synthesis and degradation of intestinal/colonic epithelium components were among the most variable functions during the intervention. We are aware that these results have been established with a single patient and will require further confirmation with a larger group of individuals and with other antibiotics. Future directions for exploration of the effects of antibiotic interventions are discussed. PMID:24418972

  18. Quantitative targeted and retrospective data analysis of relevant pesticides, antibiotics and mycotoxins in bakery products by liquid chromatography-single-stage Orbitrap mass spectrometry.

    PubMed

    De Dominicis, Emiliano; Commissati, Italo; Gritti, Elisa; Catellani, Dante; Suman, Michele

    2015-01-01

    In addition to 'traditional' multi-residue and multi-contaminant multiple reaction monitoring (MRM) mass spectrometric techniques devoted to quantifying a list of targeted compounds, the global food industry requires non-targeted methods capable of detecting other possible potentially hazardous compounds. Ultra-high-performance liquid chromatography combined with a single-stage Orbitrap high-resolution mass spectrometer (UHPLC-HRMS Exactive™-Orbitrap Technology) was successfully exploited for the complete selective and quantitative determination of 33 target compounds within three major cross categories (pesticides, antibiotics and mycotoxins) in bakery matrices (specifically milk, wheat flour and mini-cakes). Resolution was set at 50 000 full width at half maximum (FWHM) to achieve the right compromise between an adequate scan speed and selectivity, allowing for the limitations related to the necessary generic sample preparation approach. An exact mass with tolerance of 5 ppm and minimum peak threshold of 10 000 units were fixed as the main identification conditions, including retention time and isotopic pattern as additional criteria devoted to greatly reducing the risk of false-positive findings. The full validation for all the target analytes was performed: linearity, intermediate repeatability and recovery (28 analytes within 70-120%) were positively assessed; furthermore, limits of quantification between 5 and 100 µg kg(-1) (with most of the analytes having a limit of detection below 6 µg kg(-1)) indicate good performance, which is compatible with almost all the regulatory needs. Naturally contaminated and fortified mini-cakes, prepared through combined use of industrial and pilot plant production lines, were analysed at two different concentration levels, obtaining good overall quantitative results and providing preliminary indications of the potential of full-scan HRMS cluster analysis. The effectiveness of this analytical approach was also tested in

  19. Synthesis and immunological evaluation of MUC1 glycopeptide conjugates bearing N-acetyl modified STn derivatives as anticancer vaccines.

    PubMed

    Xiao, An; Zheng, Xiu-Jing; Song, Chengcheng; Gui, Yue; Huo, Chang-Xin; Ye, Xin-Shan

    2016-07-26

    Glycoprotein MUC1 is an attractive target for anti-tumor vaccine development. However, the weak immunogenicity of MUC1 remains a significant problem. To solve this problem, several STn derivatives with N-acetyl modifications were synthesized and incorporated into a 20-amino acid MUC1 tandem repeat sequence. The modified STn-MUC1 glycopeptides were further connected to a carrier protein keyhole limpet hemocyanin (KLH). The immunological effects of these synthetic vaccine conjugates were evaluated using the BALB/c mouse model. The results showed that vaccine V2 elicited higher titers of antibodies which cross-reacted with the native STn-MUC1 antigen. Moreover, the elicited antisera reacted with the STn-MUC1 antigen-positive tumor cells, indicating that the carbohydrate antigen modification strategy may hold potential to overcome the weak immunogenicity of natural MUC1 glycopeptides. PMID:27380866

  20. Microbial content and antibiotic susceptibility of bacterial isolates from yoghurts.

    PubMed

    Kyriacou, Adamantini; Tsimpidi, Eirini; Kazantzi, Evagelia; Mitsou, Eudokia; Kirtzalidou, Ekaterini; Oikonomou, Yannis; Gazis, George; Kotsou, Maria

    2008-09-01

    A total of 83 dairy products form the Greek market were examined for their bacterial populations and results were compared with the label information. The antibiotic susceptibility of the bacterial isolates was also examined. The status labeling of the yoghurts and the dairy desserts was found insufficient. The 89.8% of the cocci was found susceptible against all the 12 antibiotics examined. Lactobacillus spp. strains exhibited some kind of resistance to one or more antibiotics. The isolates of Lactobacillus delbrueckii showed resistance to one to four antibiotics, the isolates of Lactobacillus acidophilus were resistant to one to three antibiotics, while the Lactobacillus paracasei strains were resistant to four or five antibiotics. Finally, multi-resistant strains (six to nine antibiotics) were found only among the Lactobacillus rhamnosus strains. PMID:18686111

  1. Nonmedical Uses of Antibiotics: Time to Restrict Their Use?

    PubMed Central

    Meek, Richard William; Vyas, Hrushi; Piddock, Laura Jane Violet

    2015-01-01

    The global crisis of antibiotic resistance has reached a point where, if action is not taken, human medicine will enter a postantibiotic world and simple injuries could once again be life threatening. New antibiotics are needed urgently, but better use of existing agents is just as important. More appropriate use of antibiotics in medicine is vital, but the extensive use of antibiotics outside medical settings is often overlooked. Antibiotics are commonly used in animal husbandry, bee-keeping, fish farming and other forms of aquaculture, ethanol production, horticulture, antifouling paints, food preservation, and domestically. This provides multiple opportunities for the selection and spread of antibiotic-resistant bacteria. Given the current crisis, it is vital that the nonmedical use of antibiotics is critically examined and that any nonessential use halted. PMID:26444324

  2. Nonmedical Uses of Antibiotics: Time to Restrict Their Use?

    PubMed

    Meek, Richard William; Vyas, Hrushi; Piddock, Laura Jane Violet

    2015-10-01

    The global crisis of antibiotic resistance has reached a point where, if action is not taken, human medicine will enter a postantibiotic world and simple injuries could once again be life threatening. New antibiotics are needed urgently, but better use of existing agents is just as important. More appropriate use of antibiotics in medicine is vital, but the extensive use of antibiotics outside medical settings is often overlooked. Antibiotics are commonly used in animal husbandry, bee-keeping, fish farming and other forms of aquaculture, ethanol production, horticulture, antifouling paints, food preservation, and domestically. This provides multiple opportunities for the selection and spread of antibiotic-resistant bacteria. Given the current crisis, it is vital that the nonmedical use of antibiotics is critically examined and that any nonessential use halted. PMID:26444324

  3. Glycopeptide-membrane interactions: glycosyl enkephalin analogues adopt turn conformations by NMR and CD in amphipathic media.

    PubMed

    Palian, Michael M; Boguslavsky, V I; O'Brien, David F; Polt, Robin

    2003-05-14

    Four enkephalin analogues (Tyr-D-Thr-Gly-Phe-Leu-Ser-CONH(2), 1, and the related O-linked glycopeptides bearing the monosaccharide beta-glucose, 2, the disaccharide beta-maltose, 3, and the trisaccharide beta-maltotriose, 4) were synthesized, purified by HPLC, and biophysical studies were conducted to examine their interactions with membrane model systems. Glycopeptide 2 has been previously reported to penetrate the blood-brain barrier (BBB), and produce potent analgesia superior to morphine in mice (J. Med. Chem.2000, 43, 2586-90 and J. Pharm. Exp. Ther. 2001, 299, 967-972). The parent peptide and its three glycopeptide derivatives were studied in aqueous solution and in the presence of micelles using 2-D NMR, CD, and molecular mechanics (Monte Carlo studies). Consistent with previous conformational studies on cyclic opioid agonist glycopeptides, it was seen that glycosylation did not significantly perturb the peptide backbone in aqueous solution, but all four compounds strongly associated with 5-30 mM SDS or DPC micelles, and underwent profound membrane-induced conformational changes. Interaction was also observed with POPC:POPE:cholesterol lipid vesicles (LUV) in equilibrium dialysis experiments. Although the peptide backbones of 1-4 possessed random coil structures in water, in the presence of the lipid phase they each formed a nearly identical pair of structures, all with a stable beta-turn motif at the C-terminus. Use of spin labels (Mn(2+) and 5-DOXYL-stearic acid) allowed for the determination of the position and orientation of the compounds relative to the surface of the micelle. PMID:12733923

  4. 21 CFR 333.110 - First aid antibiotic active ingredients.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 5 2014-04-01 2014-04-01 false First aid antibiotic active ingredients. 333.110 Section 333.110 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE TOPICAL ANTIMICROBIAL DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE First Aid Antibiotic Drug Products § 333.110...

  5. Lysozyme as an alternative to antibiotics in swine feed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antibiotics have been fed at subtherapeutic levels to swine as growth promoters for more than 60 years, and the majority of swine produced in the U.S. receive antibiotics in their feed at some point in their production cycle. These compounds benefit the producers by minimizing production losses by ...

  6. Impact of antibiotic restrictions: the pharmaceutical perspective.

    PubMed

    Power, E

    2006-08-01

    The development of new antibiotics is dependent on their performance in economic models that favour products with large markets, high levels of potential sales and low development risks. There is a trend toward more severe and more widespread market restrictions for the use of antibiotics, ostensibly to control resistance, though they may be enacted through the control of drug budgets. The restrictions reduce the potential earnings of new antibiotics. In addition, more stringent regulatory procedures increase development costs and risk. As a consequence, compared with drugs for other diseases, particularly chronic diseases, antibiotics perform poorly in economic decision models and are therefore less likely to be selected by pharmaceutical companies for continued development. Overall, this creates a conflict between the twin objectives of controlling resistance through antibiotic restriction and addressing resistance clinically through the introduction of new agents. Ultimately, this may lead to the accelerated loss of efficacy for currently available agents, as we become more dependent on them. Moreover, the new agents that we need to maintain our current levels of health will be lacking in pharmaceutical pipelines. Antibiotic resistance is inevitable; the development of new antibiotics is, however, under threat. Unless the market conditions can be economically rebalanced to encourage innovation and investment, or new models of pharmaceutical development can be applied to this area, the number of companies with active antibiotic research programmes will continue to fall. Just as we should not be complacent regarding the development of resistance, we should not be complacent in assuming that the antibiotics of tomorrow will be there when we need them. PMID:16827822

  7. Antibiotic resistance shaping multi-level population biology of bacteria

    PubMed Central

    Baquero, Fernando; Tedim, Ana P.; Coque, Teresa M.

    2013-01-01

    Antibiotics have natural functions, mostly involving cell-to-cell signaling networks. The anthropogenic production of antibiotics, and its release in the microbiosphere results in a disturbance of these networks, antibiotic resistance tending to preserve its integrity. The cost of such adaptation is the emergence and dissemination of antibiotic resistance genes, and of all genetic and cellular vehicles in which these genes are located. Selection of the combinations of the different evolutionary units (genes, integrons, transposons, plasmids, cells, communities and microbiomes, hosts) is highly asymmetrical. Each unit of selection is a self-interested entity, exploiting the higher hierarchical unit for its own benefit, but in doing so the higher hierarchical unit might acquire critical traits for its spread because of the exploitation of the lower hierarchical unit. This interactive trade-off shapes the population biology of antibiotic resistance, a composed-complex array of the independent “population biologies.” Antibiotics modify the abundance and the interactive field of each of these units. Antibiotics increase the number and evolvability of “clinical” antibiotic resistance genes, but probably also many other genes with different primary functions but with a resistance phenotype present in the environmental resistome. Antibiotics influence the abundance, modularity, and spread of integrons, transposons, and plasmids, mostly acting on structures present before the antibiotic era. Antibiotics enrich particular bacterial lineages and clones and contribute to local clonalization processes. Antibiotics amplify particular genetic exchange communities sharing antibiotic resistance genes and platforms within microbiomes. In particular human or animal hosts, the microbiomic composition might facilitate the interactions between evolutionary units involved in antibiotic resistance. The understanding of antibiotic resistance implies expanding our knowledge on multi

  8. Classification of congenital disorders of glycosylation based on analysis of transferrin glycopeptides by capillary liquid chromatography-mass spectrometry.

    PubMed

    Barroso, Albert; Giménez, Estela; Benavente, Fernando; Barbosa, José; Sanz-Nebot, Victoria

    2016-11-01

    In this work, we describe a multivariate data analysis approach for data exploration and classification of the complex and large data sets generated to study the alteration of human transferrin (Tf) N-glycopeptides in patients with congenital disorders of glycosylation (CDG). Tf from healthy individuals and two types of CDG patients (CDG-I and CDG-II) is purified by immunoextraction from serum samples before trypsin digestion and separation by capillary liquid chromatography mass spectrometry (CapLC-MS). Following a targeted data analysis approach, partial least squares discriminant analysis (PLS-DA) is applied to the relative abundance of Tf glycopeptide glycoforms obtained after integration of the extracted ion chromatograms of the different samples. The performance of PLS-DA for classification of the different samples and for providing a novel insight into Tf glycopeptide glycoforms alteration in CDGs is demonstrated. Only six out of fourteen of the detected glycoforms are enough for an accurate classification. This small glycoform set may be considered a sensitive and specific novel biomarker panel for CDGs. PMID:27591658

  9. Solving the Antibiotic Crisis.

    PubMed

    Wright, Gerard D

    2015-02-13

    Antibiotics are essential for both treating and preventing infectious diseases. Paradoxically, despite their importance as pillars of modern medicine, we are in danger of losing antibiotics because of the evolution and dissemination of resistance mechanisms throughout all pathogenic microbes. This fact, coupled with an inability to bring new drugs to market at a pace that matches resistance, has resulted in a crisis of global proportion. Solving this crisis requires the actions of many stakeholders, but chemists, chemical biologists, and microbiologists must drive the scientific innovation that is required to maintain our antibiotic arsenal. This innovation requires (1) a deep understanding of the evolution and reservoirs of resistance; (2) full knowledge of the molecular mechanisms of antibiotic action and resistance; (3) the discovery of chemical and genetic probes of antibiotic action and resistance; (4) the integration of systems biology into antibiotic discovery; and (5) the discovery of new antimicrobial chemical matter. Addressing these pressing scientific gaps will ensure that we can meet the antibiotic crisis with creativity and purpose. PMID:27622298

  10. Antibiotic Application and Emergence of Multiple Antibiotic Resistance (MAR) in Global Catfish Aquaculture.

    PubMed

    Chuah, Li-Oon; Effarizah, M E; Goni, Abatcha Mustapha; Rusul, Gulam

    2016-06-01

    Catfish is one of the most cultivated species worldwide. Antibiotics are usually used in catfish farming as therapeutic and prophylactic agents. In the USA, only oxytetracycline, a combination of sulfadimethoxine and ormetoprim, and florfenicol are approved by the Food Drug Administration for specific fish species (e.g., catfish and salmonids) and their specific diseases. Misuse of antibiotics as prophylactic agents in disease prevention, however, is common and contributes in the development of antibiotic resistance. Various studies had reported on antibiotic residues and/or resistance in farmed species, feral fish, water column, sediments, and, in a lesser content, among farm workers. Ninety percent of the world aquaculture production is carried out in developing countries, which lack regulations and enforcement on the use of antibiotics. Hence, efforts are needed to promote the development and enforcement of such a regulatory structure. Alternatives to antibiotics such as antibacterial vaccines, bacteriophages and their lysins, and probiotics have been applied to curtail the increasing emergence of antibiotic-resistant bacteria due to the imprudent application of antibiotics in aquaculture. PMID:27038482

  11. Analysis of 27 antibiotic residues in raw cow's milk and milk-based products--validation of Delvotest® T.

    PubMed

    Bion, Cindy; Beck Henzelin, Andrea; Qu, Yajuan; Pizzocri, Giuseppe; Bolzoni, Giuseppe; Buffoli, Elena

    2016-01-01

    Delvotest® T was evaluated for its capability at detecting residues of 27 antibiotics in raw cow's milk and in some dairy ingredients (skimmed and full-cream milk powders). The kit was used as a screening tool for the qualitative determination of antibiotics from different families in a single test. Results delivered by such a method are expressed as 'positive' or 'negative', referring to the claimed screening target concentration (STC). Validation was conducted according to the European Community Reference Laboratories' (CRLs) residues guidelines of 20 January 2010 and performed by two laboratories, one located in Europe and the other in Asia. Five criteria were evaluated including detection capability at STC, false-positive (FP) rate, false-negative (FN) rate, robustness and cross-reactivity using visual reading and Delvoscan®. STCs were set at or below the corresponding maximum residue limit (MRL), as fixed by European Regulation EC No. 37/2010. Four antibiotics (nafcillin, oxytetracycline, tetracycline and rifaximin) out of 27 had a false-negative rate ranging from 1.7% to 4.9%; however, it was still compliant with the CRLs' requirements. Globally, Delvotest T can be recommended for the analysis of the surveyed antibiotics in raw cow's milk, skimmed and full-cream milk powders. Additional compounds were tested such as sulfamethazine, spiramycin and erythromycin; however, detection at the corresponding MRL was not achievable and these compounds were removed from the validation. Other drugs from the sulfonamide, aminoglycoside or macrolide families not detected by the test at the MRL were not evaluated in this study. Regarding the reliability of this rapid test to milk-based preparations, additional experiments should be performed on a larger range of compounds and samples to validate the Delvotest T in such matrices. PMID:26555933

  12. Resistance to Antibiotics and Antifungal Medicinal Products: Can Complementary and Alternative Medicine Help Solve the Problem in Common Infection Diseases? The Introduction of a Dutch Research Consortium

    PubMed Central

    Kok, Esther T.; Jong, Miek C.; Gravendeel, Barbara; Van Leeuwen, Willem B.; Baars, Erik W.

    2015-01-01

    The increase of antibiotic resistance worldwide, rising numbers of deaths and costs associated with this, and the fact that hardly any new antimicrobial drugs have been developed during the last decade have increased the interest in Complementary and Alternative Medicine (CAM) therapeutic interventions, if proven safe and effective. Observational studies on clinical CAM practices demonstrate positive effects of treatment of infections with CAM therapies (clinical effects, patient satisfaction) in combination with small percentages of antibiotics prescription. However, Cochrane reviews and other studies demonstrate that in most instances the quality of clinical trials on CAM treatment of infections is currently too low to provide sufficient evidence. Therefore a Dutch consortium on (in vitro and clinical) scientific research on CAM and antibiotic resistance has been formed. The aim and objective of the consortium is to establish an enduring partnership and to develop expertise to further develop and investigate safe and effective CAM treatments for infectious diseases of humans (and animals). A first ongoing project on the development of safe and effective biobased CAM antimycotics in women with (recurrent) vaginal candidiasis infection is introduced. PMID:26539227

  13. Handling Time-dependent Variables: Antibiotics and Antibiotic Resistance.

    PubMed

    Munoz-Price, L Silvia; Frencken, Jos F; Tarima, Sergey; Bonten, Marc

    2016-06-15

    Elucidating quantitative associations between antibiotic exposure and antibiotic resistance development is important. In the absence of randomized trials, observational studies are the next best alternative to derive such estimates. Yet, as antibiotics are prescribed for varying time periods, antibiotics constitute time-dependent exposures. Cox regression models are suited for determining such associations. After explaining the concepts of hazard, hazard ratio, and proportional hazards, the effects of treating antibiotic exposure as fixed or time-dependent variables are illustrated and discussed. Wider acceptance of these techniques will improve quantification of the effects of antibiotics on antibiotic resistance development and provide better evidence for guideline recommendations. PMID:27025824

  14. Antibiotic / Antimicrobial Resistance Glossary

    MedlinePlus

    ... on the Farm Get Smart About Antibiotics Week File Formats Help: How do I view different file formats (PDF, DOC, PPT, MPEG) on this site? Adobe PDF file Microsoft PowerPoint file Microsoft Word file Microsoft Excel ...

  15. Targeting Antibiotic Resistance.

    PubMed

    Chellat, Mathieu F; Raguž, Luka; Riedl, Rainer

    2016-06-01

    Finding strategies against the development of antibiotic resistance is a major global challenge for the life sciences community and for public health. The past decades have seen a dramatic worldwide increase in human-pathogenic bacteria that are resistant to one or multiple antibiotics. More and more infections caused by resistant microorganisms fail to respond to conventional treatment, and in some cases, even last-resort antibiotics have lost their power. In addition, industry pipelines for the development of novel antibiotics have run dry over the past decades. A recent world health day by the World Health Organization titled "Combat drug resistance: no action today means no cure tomorrow" triggered an increase in research activity, and several promising strategies have been developed to restore treatment options against infections by resistant bacterial pathogens. PMID:27000559

  16. Colds and flus - antibiotics

    MedlinePlus

    Antibiotics - colds and flu ... treat infections that are caused by a virus. Colds and flu are caused by viruses. If you ... Hamilton A. Treatments for symptoms of the common cold. Am Fam Physician. 2013;88(12):Online. PMID: ...

  17. Adverse antibiotic drug interactions.

    PubMed

    Bint, A J; Burtt, I

    1980-07-01

    There is enormous potential for drug interactions in patients who, today, often receive many drugs. Antibiotics are prominent amongst the groups of drugs commonly prescribed. Many interactions take place at the absorption stage. Antacids and antidiarrhoeal preparations, in particular, can delay and reduce the absorption of antibiotics such as tetracyclines and clindamycin, by combining with them in the gastrointestinal tract to form chelates or complexes. Other drugs can affect gastric motility, which in turn often controls the rate at which antibiotics are absorbed. Some broad spectrum antibiotics can alter the bacterial flora of the gut which may be related to malabsorption states. The potentiation of toxic side effects of one drug by another is a common type of interaction. Antibiotics which are implicated in this type of interaction are those which themselves possess some toxicity such as aminoglycosides, some cephalosporins, tetracyclines and colistin. Some of the most important adverse interactions with antibiotics are those which involve other drugs which have a low toxicity/efficacy ratio. These include anticoagulants such as warfarin, anticonvulsants such as phenytoin and phenobarbitone and oral antidiabetic drugs like tolbutamide. Risk of interaction arises when the metabolism of these drugs is inhibited by liver microsomal enzyme inhibitors such as some sulphonamides and chloramphenicol, or is enhanced by enzyme inducers such as rifampicin. PMID:6995091

  18. [The history of antibiotics].

    PubMed

    Yazdankhah, Siamak; Lassen, Jørgen; Midtvedt, Tore; Solberg, Claus Ola

    2013-12-10

    The development of chemical compounds for the treatment of infectious diseases may be divided into three phases: a) the discovery in the 1600s in South America of alkaloid extracts from the bark of the cinchona tree and from the dried root of the ipecacuanha bush, which proved effective against, respectively, malaria (quinine) and amoebic dysentery (emetine); b) the development of synthetic drugs, which mostly took place in Germany, starting with Paul Ehrlich's (1854-1915) discovery of salvarsan (1909), and crowned with Gerhard Domagk's (1895-1964) discovery of the sulfonamides (1930s); and c) the discovery of antibiotics. The prime example of the latter is the development of penicillin in the late 1920s following a discovery by a solitary research scientist who never worked in a team and never as part of a research programme. It took another ten years or so before drug-quality penicillin was produced, with research now dependent on being conducted in large collaborative teams, frequently between universities and wealthy industrial companies. The search for new antibiotics began in earnest in the latter half of the 1940s and was mostly based on soil microorganisms. Many new antibiotics were discovered in this period, which may be termed «the golden age of antibiotics». Over the past three decades, the development of new antibiotics has largely stalled, while antibiotic resistance has increased. This situation may require new strategies for the treatment of infectious diseases. PMID:24326504

  19. [Analysis of antibiotic usage].

    PubMed

    Balpataki, R; Balogh, J; Zelkó, R; Vincze, Z

    2001-01-01

    Economic analysis is founded on the assumption that resources are limited and that should be used in a way that maximizes the benefits gained. Pharmacoeconomics extends these assumptions to drug treatment. Therefore, a full pharmacoeconomic analysis must consider two or more alternative treatments and should be founded on measurement of incremental cost, incremental efficacy, and the value of successful outcome. Antibiotic policy based only on administrative restrictions is failed, instead of it disease formularies and infectologist consultation system are needed. Equally important are various programmes that encourage the cost-conscious use of the antibiotics chosen. Some of the methods evaluated in the literature include: streamlining from combination therapy to a single agent, early switching from parenteral to oral therapy, initiating treatment with oral agents, administering parenteral antibiotic at home from outset of therapy, and antibiotic streamlining programmes that are partnered with infectious disease physicians. The solution is the rational and adequate use of antibiotics, based on the modern theory and practice of antibiotic policy and infection control, that cannot be carried out without the activities of experts in this field. PMID:11769090

  20. [Prophylactic antibiotics in neurosurgery].

    PubMed

    Iacob, G; Iacob, Simona; Cojocaru, Inimioara

    2007-01-01

    Because of a low risk of infection (around 2-3%), prophylactic use of antibiotics in neurosurgery is a controversial issue. Some neurosurgeons consider that there are strong arguments against the use of antimicrobials (promotion of antibiotic-resistant strains of bacteria, superinfection and adverse drug reactions) and meticulous aseptic techniques could be more usefully than prophylactic antibiotics. On the other hand, despite of being rare, the consequences of a neurosurgical infection can be dramatic and may result in a rapid death, caused by meningitis, cerebritis, abscess formation or sepsis. Clinical studies emphasized that the most important factors influencing the choice of antibiotic prophylaxis in neurosurgery is the patient's immune status, virulence of the pathogens and the type of surgery ("clean contaminated"--procedure that crosses the cranial sinuses, "clean non-implant"--procedure that does not cross the cranial sinuses, CSF shunt surgery, skull fracture). Prophylaxis has become the standard of care for contaminated and clean-contaminated surgery, also for surgery involving insertion of artificial devices. The antibiotic (first/second generation of cephalosporins or vancomycin in allergic patients) should recover only the cutaneous possibly contaminating flora (S. aureus, S. epidermidis) and should be administrated 30' before the surgical incision, intravenously in a single dose. Most studies pointed that identification of the risk factors for infections, correct asepsis and minimal prophylactic antibiotic regimen, help neurosurgeons to improve patient care and to decrease mortality without selecting resistant bacteria. PMID:18293694

  1. Strategies to Minimize Antibiotic Resistance

    PubMed Central

    Lee, Chang-Ro; Cho, Ill Hwan; Jeong, Byeong Chul; Lee, Sang Hee

    2013-01-01

    Antibiotic resistance can be reduced by using antibiotics prudently based on guidelines of antimicrobial stewardship programs (ASPs) and various data such as pharmacokinetic (PK) and pharmacodynamic (PD) properties of antibiotics, diagnostic testing, antimicrobial susceptibility testing (AST), clinical response, and effects on the microbiota, as well as by new antibiotic developments. The controlled use of antibiotics in food animals is another cornerstone among efforts to reduce antibiotic resistance. All major resistance-control strategies recommend education for patients, children (e.g., through schools and day care), the public, and relevant healthcare professionals (e.g., primary-care physicians, pharmacists, and medical students) regarding unique features of bacterial infections and antibiotics, prudent antibiotic prescribing as a positive construct, and personal hygiene (e.g., handwashing). The problem of antibiotic resistance can be minimized only by concerted efforts of all members of society for ensuring the continued efficiency of antibiotics. PMID:24036486

  2. Longitudinal monitoring of immunoglobulin A glycosylation during pregnancy by simultaneous MALDI-FTICR-MS analysis of N- and O-glycopeptides

    PubMed Central

    Bondt, Albert; Nicolardi, Simone; Jansen, Bas C.; Stavenhagen, Kathrin; Blank, Dennis; Kammeijer, Guinevere S. M.; Kozak, Radoslaw P.; Fernandes, Daryl L.; Hensbergen, Paul J.; Hazes, Johanna M. W.; van der Burgt, Yuri E. M.; Dolhain, Radboud J. E. M.; Wuhrer, Manfred

    2016-01-01

    Immunoglobulin A (IgA) is a glycoprotein of which altered glycosylation has been associated with several pathologies. Conventional methods for IgA N- and O-glycosylation analysis are tedious, thus limiting such analyses to small sample sizes. Here we present a high-throughput strategy for the simultaneous analysis of serum-derived IgA1 N- and O-glycopeptides using matrix-assisted laser/desorption ionisation Fourier transform ion cyclotron resonance (MALDI-FTICR) mass spectrometry (MS). Six non-fucosylated diantennary complex type glycoforms were detected on the Asn144-containing glycopeptide. Thirteen distinct glycoforms were identified for the Asn340-containing tailpiece glycopeptide, mainly of the diantennary complex type, and low amounts of triantennary glycoforms. Simultaneously with these N-glycopeptides, 53 compositional glycoforms of the hinge region O-glycopeptide were profiled in a single high resolution MALDI-FTICR spectrum. Since many pregnancy associated changes have been recognized for immunoglobulin G, we sought to demonstrate the clinical applicability of this method in a cohort of 29 pregnant women, from whom samples were collected at three time points during pregnancy and three time points after delivery. Pregnancy associated changes of N-glycan bisection were different for IgA1 as compared to IgG-Fc described earlier. We foresee further applications of the developed method for larger patient cohorts to study IgA N- and O-glycosylation changes in pathologies. PMID:27302155

  3. Longitudinal monitoring of immunoglobulin A glycosylation during pregnancy by simultaneous MALDI-FTICR-MS analysis of N- and O-glycopeptides.

    PubMed

    Bondt, Albert; Nicolardi, Simone; Jansen, Bas C; Stavenhagen, Kathrin; Blank, Dennis; Kammeijer, Guinevere S M; Kozak, Radoslaw P; Fernandes, Daryl L; Hensbergen, Paul J; Hazes, Johanna M W; van der Burgt, Yuri E M; Dolhain, Radboud J E M; Wuhrer, Manfred

    2016-01-01

    Immunoglobulin A (IgA) is a glycoprotein of which altered glycosylation has been associated with several pathologies. Conventional methods for IgA N- and O-glycosylation analysis are tedious, thus limiting such analyses to small sample sizes. Here we present a high-throughput strategy for the simultaneous analysis of serum-derived IgA1 N- and O-glycopeptides using matrix-assisted laser/desorption ionisation Fourier transform ion cyclotron resonance (MALDI-FTICR) mass spectrometry (MS). Six non-fucosylated diantennary complex type glycoforms were detected on the Asn144-containing glycopeptide. Thirteen distinct glycoforms were identified for the Asn340-containing tailpiece glycopeptide, mainly of the diantennary complex type, and low amounts of triantennary glycoforms. Simultaneously with these N-glycopeptides, 53 compositional glycoforms of the hinge region O-glycopeptide were profiled in a single high resolution MALDI-FTICR spectrum. Since many pregnancy associated changes have been recognized for immunoglobulin G, we sought to demonstrate the clinical applicability of this method in a cohort of 29 pregnant women, from whom samples were collected at three time points during pregnancy and three time points after delivery. Pregnancy associated changes of N-glycan bisection were different for IgA1 as compared to IgG-Fc described earlier. We foresee further applications of the developed method for larger patient cohorts to study IgA N- and O-glycosylation changes in pathologies. PMID:27302155

  4. Isotope-targeted glycoproteomics (IsoTaG): a mass-independent platform for intact N- and O-glycopeptide discovery and analysis

    PubMed Central

    Woo, Christina M; Iavarone, Anthony T; Spiciarich, David R; Palaniappan, Krishnan K; Bertozzi, Carolyn R

    2015-01-01

    Protein glycosylation is a heterogeneous post-translational modification (PTM) that plays an essential role in biological regulation. However, the diversity found in glycoproteins has undermined efforts to describe the intact glycoproteome via mass spectrometry (MS). We present IsoTaG, a mass-independent chemical glycoproteomics platform for characterization of intact, metabolically labeled glycopeptides at the whole-proteome scale. In IsoTaG, metabolic labeling of the glycoproteome is combined with (i) chemical enrichment and isotopic recoding of glycopeptides to select peptides for targeted glycoproteomics using directed MS and (ii) mass-independent assignment of intact glycopeptides. We structurally assigned 32 N-glycopeptides and over 500 intact and fully elaborated O-glycopeptides from 250 proteins across three human cancer cell lines and also discovered unexpected peptide sequence polymorphisms (pSPs). The IsoTaG platform is broadly applicable to the discovery of PTM sites that are amenable to chemical labeling, as well as previously unknown protein isoforms including pSPs. PMID:25894945

  5. Semi-automated identification of N-Glycopeptides by hydrophilic interaction chromatography, nano-reverse-phase LC-MS/MS, and glycan database search.

    PubMed

    Pompach, Petr; Chandler, Kevin B; Lan, Renny; Edwards, Nathan; Goldman, Radoslav

    2012-03-01

    Glycoproteins fulfill many indispensable biological functions, and changes in protein glycosylation have been observed in various diseases. Improved analytical methods are needed to allow a complete characterization of this complex and common post-translational modification. In this study, we present a workflow for the analysis of the microheterogeneity of N-glycoproteins that couples hydrophilic interaction and nanoreverse-phase C18 chromatography to tandem QTOF mass spectrometric analysis. A glycan database search program, GlycoPeptideSearch, was developed to match N-glycopeptide MS/MS spectra with the glycopeptides comprised of a glycan drawn from the GlycomeDB glycan structure database and a peptide from a user-specified set of potentially glycosylated peptides. Application of the workflow to human haptoglobin and hemopexin, two microheterogeneous N-glycoproteins, identified a total of 57 distinct site-specific glycoforms in the case of haptoglobin and 14 site-specific glycoforms of hemopexin. Using glycan oxonium ions and peptide-characteristic glycopeptide fragment ions and by collapsing topologically redundant glycans, the search software was able to make unique N-glycopeptide assignments for 51% of assigned spectra, with the remaining assignments primarily representing isobaric topological rearrangements. The optimized workflow, coupled with GlycoPeptideSearch, is expected to make high-throughput semiautomated glycopeptide identification feasible for a wide range of users. PMID:22239659

  6. Presence and in vivo biosynthesis of fragments of CPP (the C-terminal glycopeptide of the rat vasopressin precursor) in the hypothalamo-neurohypophyseal system

    SciTech Connect

    Seger, M.A.; Burbach, J.P.

    1987-09-01

    The existence and rate of formation of fragments of the 39-residue C-terminal glycopeptide of propressophysin (CPP1-39) was investigated in the hypothalamo-neurohypophyseal system. Newly-prepared antisera to CPP were used to confirm the existence of smaller C-terminal fragments derived from CPP1-39. Radiolabelled fucose was injected into rats in vivo into the area of the supraoptic nucleus, and the labelled peptides formed in the neurohypophysis were examined at various time intervals up to five weeks after the injection. The products derived from the neurohypophyseal hormone precursors were separated by high-performance liquid chromatography. The level of the major immunoreactive C-terminal fragment (CPP22-39) was constant and represented about 5% of the intact CPP1-39 in the neurohypophysis. The appearance of newly-synthesized N-terminal fragment of CPP1-39 occurred only after 3 or 4 days. This fucose labelled fragment increased slowly thereafter until it reached the same level as the CPP C-terminal fragment immunoreactivity between 21 and 28 days after injection. The results suggest that CPP1-39 is extremely stable in the hypothalamo-neurohypophyseal neurons, and that the cleavage at Arg21-Leu22 is a delayed proteolytic event in the magnocellular neurons of the SON.

  7. The Antitumor Effect of Gekko Sulfated Glycopeptide by Inhibiting bFGF-Induced Lymphangiogenesis

    PubMed Central

    Ding, Xiu-Li; Man, Ya-Nan; Hao, Jian; Zhu, Cui-Hong; Liu, Chang; Yang, Xue

    2016-01-01

    Objective. To study the antilymphangiogenesis effect of Gekko Sulfated Glycopeptide (GSPP) on human lymphatic endothelial cells (hLECs). Methods. MTS was conducted to confirm the antiproliferation effect of GSPP on hLECs; flow cytometry was employed to detect hLECs cycle distribution; the antimigration effect of GSPP on hLECs was investigated by wound healing experiment and transwell experiment; tube formation assay was used to examine its inhibitory effect on the lymphangiogenesis; western blotting was conducted to detect the expression of extracellular signal-regulated kinase1/2 (Erk1/2) and p-Erk1/2 after GSPP and basic fibroblast growth factor (bFGF) treatment. Nude mice models were established to investigate the antitumor effect of GSPP in vivo. Decreased lymphangiogenesis caused by GSPP in vivo was verified by immunohistochemical staining. Results. In vitro, GSPP (10 μg/mL, 100 μg/mL) significantly inhibited bFGF-induced hLECs proliferation, migration, and tube-like structure formation (P < 0.05) and antagonized the phosphorylation activation of Erk1/2 induced by bFGF. In vivo, GSPP treatment (200 mg/kg/d) not only inhibited the growth of colon carcinoma, but also inhibited the tumor lymphangiogenesis. Conclusion. GSPP possesses the antitumor ability by inhibiting bFGF-inducing lymphangiogenesis in vitro and in vivo, which may further inhibit tumor lymphatic metastasis. PMID:27190997

  8. Can Amphipathic Helices Influence the CNS Antinociceptive Activity of Glycopeptides Related to β-Endorphin?

    PubMed Central

    2015-01-01

    Glycosylated β-endorphin analogues of various amphipathicity were studied in vitro and in vivo in mice. Opioid binding affinities of the O-linked glycopeptides (mono- or disaccharides) and unglycosylated peptide controls were measured in human receptors expressed in CHO cells. All were pan-agonists, binding to μ-, δ-, or κ-opioid receptors in the low nanomolar range (2.2–35 nM Ki’s). The glycoside moiety was required for intravenous (i.v.) but not for intracerebroventricular (i.c.v.) activity. Circular dichroism and NMR indicated the degree of helicity in H2O, aqueous trifluoroethanol, or micelles. Glycosylation was essential for activity after i.v. administration. It was possible to manipulate the degree of helicity by the alteration of only two amino acid residues in the helical address region of the β-endorphin analogues without destroying μ-, δ-, or κ-agonism, but the antinociceptive activity after i.v. administration could not be directly correlated to the degree of helicity in micelles. PMID:24576160

  9. Comparative glycomics of the glycoprotein follicle stimulating hormone: glycopeptide analysis of isolates from two mammalian species.

    PubMed

    Dalpathado, Dilusha S; Irungu, Janet; Go, Eden P; Butnev, Vladimir Y; Norton, Katie; Bousfield, George R; Desaire, Heather

    2006-07-18

    Follicle stimulating hormone (FSH) is one of the important hormones that regulate gonadal functions. This hormone is glycosylated, and the glycans greatly influence the biological properties. In the present study the negatively charged glycopeptides of equine and human pituitary follicle stimulating hormone (eFSH and hFSH) have been characterized in a glycosylation site-specific manner using FT-ICR-MS and Edman sequencing. The characteristic pattern of glycan distribution at each glycosylation site has been deduced and compared between horse and human FSH preparations. The data suggest that site-specific differences exist between glycoforms of human and equine FSH. For instance, except for one site in the beta subunit (Asn7) of hFSH all other sites in both species have sulfated glycoforms. Also, glycoforms at Asn52 of hFSH are all complex type, whereas in eFSH, both complex and hybrid structures exist at this site. There is also a higher percentage of sulfated glycans in the latter site compared to the former. This is the first study that characterizes the glycans from this hormone in a glycosylation site-specific manner, and these data can be used to begin correlative studies between glycosylation structure and hormone function. PMID:16834341

  10. The Antitumor Effect of Gekko Sulfated Glycopeptide by Inhibiting bFGF-Induced Lymphangiogenesis.

    PubMed

    Ding, Xiu-Li; Man, Ya-Nan; Hao, Jian; Zhu, Cui-Hong; Liu, Chang; Yang, Xue; Wu, Xiong-Zhi

    2016-01-01

    Objective. To study the antilymphangiogenesis effect of Gekko Sulfated Glycopeptide (GSPP) on human lymphatic endothelial cells (hLECs). Methods. MTS was conducted to confirm the antiproliferation effect of GSPP on hLECs; flow cytometry was employed to detect hLECs cycle distribution; the antimigration effect of GSPP on hLECs was investigated by wound healing experiment and transwell experiment; tube formation assay was used to examine its inhibitory effect on the lymphangiogenesis; western blotting was conducted to detect the expression of extracellular signal-regulated kinase1/2 (Erk1/2) and p-Erk1/2 after GSPP and basic fibroblast growth factor (bFGF) treatment. Nude mice models were established to investigate the antitumor effect of GSPP in vivo. Decreased lymphangiogenesis caused by GSPP in vivo was verified by immunohistochemical staining. Results. In vitro, GSPP (10 μg/mL, 100 μg/mL) significantly inhibited bFGF-induced hLECs proliferation, migration, and tube-like structure formation (P < 0.05) and antagonized the phosphorylation activation of Erk1/2 induced by bFGF. In vivo, GSPP treatment (200 mg/kg/d) not only inhibited the growth of colon carcinoma, but also inhibited the tumor lymphangiogenesis. Conclusion. GSPP possesses the antitumor ability by inhibiting bFGF-inducing lymphangiogenesis in vitro and in vivo, which may further inhibit tumor lymphatic metastasis. PMID:27190997

  11. Enzymatic glycoprotein synthesis: Preparation of ribonuclease glycoforms via enzymatic glycopeptide condensation and glycosylation

    SciTech Connect

    Witte, K.; Sears, P.; Martin, R.; Wong, C.H.

    1997-03-05

    In order to study the effects carbohydrates have on glycoprotein structure and funciton, it is imperative to be able to synthesize the appropriate natural and non-natural glycoprotein variants in a single form. Because the available in vivo techniques provide only heterogeneous mixtures of different glycoforms, enzymatic in vitro methodologies have been pursued. Using the N-glycoprotein RNase B as a model system, the oligosaccharide was removed leaving only the N-acetylglucosamine as a `tag` to the site of glycosylation. Glycosyltransferases were then used to build a unique carbohydrate moiety. A new RNase glycoform containing the branched oligosccharide, sialyl Lewis X or the Hg derivative, was synthesized enzymatically to demonstrate the feasibility of the method. In addition, the monoglycosylated protein was digested into several smaller pieces by subtilisin BPN`. These fragments were religated by subtilisin 8397 to the full length RNase by addition glycerol; this method points to a new chemical-enzymatic process for the synthesis of glycoproteins using synthetic peptides and glycopeptides as substrates for enzymatic ligation followed by further enzymatic glycosylations. 29 refs., 6 figs.

  12. Characterization of Monoclonal Antibody LpMab-3 Recognizing Sialylated Glycopeptide of Podoplanin

    PubMed Central

    Oki, Hiroharu; Ogasawara, Satoshi; Kaneko, Mika Kato; Takagi, Michiaki; Yamauchi, Masanori

    2015-01-01

    Podoplanin (PDPN/Aggrus/T1α/gp36/OTS-8), a type I transmembrane sialoglycoprotein, is involved in platelet aggregation, cell invasion, and cancer metastasis. Podoplanin expression in cancer cells or cancer-associated fibroblasts was reported to be involved in poor prognosis of several cancers. Furthermore, podoplanin is expressed in lymphatic endothelial cells or lung type I alveolar cells. Although many anti-podoplanin monoclonal antibodies (MAbs), such as NZ-1 and D2–40, have been established, almost all anti-podoplanin MAbs are produced against a platelet aggregation-inducing (PLAG) domain. In this study, we produced and characterized a novel anti-podoplanin monoclonal antibody, LpMab-3, the epitope of which is a sialylated glycopeptide of podoplanin. We identified the minimum epitope of LpMab-3 as Thr76–Glu81 of human podoplanin, which is different from PLAG domain, using Western blot analysis and flow cytometry. Immunohistochemical analysis showed that LpMab-3 is useful for detecting lung type I alveolar cells and lymphatic endothelial cells. Because LpMab-3 detects only sialylated podoplanin, it could be useful for uncovering the physiological function of sialylated human podoplanin. PMID:25723283

  13. Rapid fabrication of functionalized plates for peptides, glycopeptides and protein purification and mass spectrometry analysis.

    PubMed

    Liao, Hsin-Yi; Tsai, Fuu-Jen; Lai, Chien-Chen; Tseng, Mei-Chun; Hsu, Chung Y; Chen, Chao-Jung

    2016-04-01

    A rapid and simple approach for fabricating a disposable functionalized membrane on matrix-assisted laser desorption ionization (MALDI) targets, glass, or plastic substrates, without using complex mechanical protocols or chemical reactions, was developed for sample enrichment and mass spectrometry analysis. By coating functionalized-silica particles on a polydimethylsiloxane (PDMS)-coated plate, these particles can form a monolayer of materials on the PDMS membrane for sample handling without peeling off. An octadecyl(C18)-functionalized plate was fabricated by coating porous C18-silica particles on a PDMS-coated plate. The C18 particle-coated PDMS plate (CP plate) has better sensitivity than C18 tips and magnetic nanoparticles, along with a higher sample recovery (64.3 ± 4.9%) compared to the C18 tip method, when analyzing trace amounts of 5 fm BSA digest samples. The CP plate shows significantly higher urea/SDS removal efficiency on the cell lysate proteome compared to C18 tips. The capacity of the C18 spot (∼2.8 mm in diameter) on the CP plate was ∼10 μg of BSA digests. A hydrophilic particle-coated PDMS plate was also fabricated and successfully used for glycopeptide enrichment and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis. PMID:26948663

  14. Antiaging Glycopeptide Protects Human Islets Against Tacrolimus-Related Injury and Facilitates Engraftment in Mice.

    PubMed

    Gala-Lopez, Boris L; Pepper, Andrew R; Pawlick, Rena L; O'Gorman, Doug; Kin, Tatsuya; Bruni, Antonio; Abualhassan, Nasser; Bral, Mariusz; Bautista, Austin; Manning Fox, Jocelyn E; Young, Lachlan G; MacDonald, Patrick E; Shapiro, A M James

    2016-02-01

    Clinical islet transplantation has become an established treatment modality for selected patients with type 1 diabetes. However, a large proportion of transplanted islets is lost through multiple factors, including immunosuppressant-related toxicity, often requiring more than one donor to achieve insulin independence. On the basis of the cytoprotective capabilities of antifreeze proteins (AFPs), we hypothesized that supplementation of islets with synthetic AFP analog antiaging glycopeptide (AAGP) would enhance posttransplant engraftment and function and protect against tacrolimus (Tac) toxicity. In vitro and in vivo islet Tac exposure elicited significant but reversible reduction in insulin secretion in both mouse and human islets. Supplementation with AAGP resulted in improvement of islet survival (Tac(+) vs. Tac+AAGP, 31.5% vs. 67.6%, P < 0.01) coupled with better insulin secretion (area under the curve: Tac(+) vs. Tac+AAGP, 7.3 vs. 129.2 mmol/L/60 min, P < 0.001). The addition of AAGP reduced oxidative stress, enhanced insulin exocytosis, improved apoptosis, and improved engraftment in mice by decreasing expression of interleukin (IL)-1β, IL-6, keratinocyte chemokine, and tumor necrosis factor-α. Finally, transplant efficacy was superior in the Tac+AAGP group and was similar to islets not exposed to Tac, despite receiving continuous treatment for a limited time. Thus, supplementation with AAGP during culture improves islet potency and attenuates long-term Tac-induced graft dysfunction. PMID:26581595

  15. Antibiotic therapy for ocular infection.

    PubMed Central

    Snyder, R W; Glasser, D B

    1994-01-01

    Infections of the eye can rapidly damage important functional structures and lead to permanent vision loss or blindness. Broad-spectrum antibiotics should be administered to the appropriate site of infection as soon as a diagnosis is made. Topical drops are preferred for corneal and conjunctival infections. Intravitreal antibiotics, and possibly subconjunctival and parenteral antibiotics, are preferred for endophthalmitis. Parenteral antibiotics are recommended for infection in deep adnexal structures. We review specific aspects of antibiotic therapy for ocular and periocular infection. PMID:7856158

  16. Accumulation of the Antibiotic Phenazine-1-Carboxylic Acid in the Rhizosphere of Dryland Cereals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Natural antibiotics are thought to function in the defense, fitness, competitiveness, biocontrol activity, communication and gene regulation of microorganisms. However, the scale and quantitative aspects of antibiotic production in natural settings are poorly understood. We addressed these fundament...

  17. Burkholderia cepacia complex Phage-Antibiotic Synergy (PAS): antibiotics stimulate lytic phage activity.

    PubMed

    Kamal, Fatima; Dennis, Jonathan J

    2015-02-01

    The Burkholderia cepacia complex (Bcc) is a group of at least 18 species of Gram-negative opportunistic pathogens that can cause chronic lung infection in cystic fibrosis (CF) patients. Bcc organisms possess high levels of innate antimicrobial resistance, and alternative therapeutic strategies are urgently needed. One proposed alternative treatment is phage therapy, the therapeutic application of bacterial viruses (or bacteriophages). Recently, some phages have been observed to form larger plaques in the presence of sublethal concentrations of certain antibiotics; this effect has been termed phage-antibiotic synergy (PAS). Those reports suggest that some antibiotics stimulate increased production of phages under certain conditions. The aim of this study is to examine PAS in phages that infect Burkholderia cenocepacia strains C6433 and K56-2. Bcc phages KS12 and KS14 were tested for PAS, using 6 antibiotics representing 4 different drug classes. Of the antibiotics tested, the most pronounced effects were observed for meropenem, ciprofloxacin, and tetracycline. When grown with subinhibitory concentrations of these three antibiotics, cells developed a chain-like arrangement, an elongated morphology, and a clustered arrangement, respectively. When treated with progressively higher antibiotic concentrations, both the sizes of plaques and phage titers increased, up to a maximum. B. cenocepacia K56-2-infected Galleria mellonella larvae treated with phage KS12 and low-dose meropenem demonstrated increased survival over controls treated with KS12 or antibiotic alone. These results suggest that antibiotics can be combined with phages to stimulate increased phage production and/or activity and thus improve the efficacy of bacterial killing. PMID:25452284

  18. Natural antibiotic susceptibility of Escherichia coli, Shigella, E. vulneris, and E. hermannii strains.

    PubMed

    Stock, I; Wiedemann, B

    1999-03-01

    The natural antibiotic susceptibility of 139 Escherichia coli strains (including 18 enterohemorrhagic E. coli), 73 Shigella strains (S. sonnei (n = 37), S. flexneri (n = 29), S. boydii (n = 6), S. dysenteriae (n = 1)), 23 E. vulneris, and 20 E. hermannii strains toward 71 antibiotics was examined. MICs were determined using a microdilution procedure. All examined taxa were naturally sensitive/intermediate toward tetracyclines, aminoglycosides, some penicillins (amoxycillin/clavulanate, ampicillin/sulbactam, piperacillin [with and without tazobactam], mezlocillin, azlocillin), cephalosporins, carbapenems, monobactams, quinolones, trimethoprim, cotrimoxazole, and chloramphenicol and were naturally resistant/intermediate toward benzylpenicillin, oxacillin, macrolides, lincosamides, glycopeptides, rifampicin, and fusidic acid. No differences in natural antibiotic susceptibility were seen between enterohemorrhagic and other E. coli strains. Likewise, with one exception, no significant differences in natural antibiotic susceptibility were seen either among the Shigella subgroups or between Shigella and E. coli. The natural population of S. flexneri was slightly more susceptible to chloramphenicol than the natural populations of other taxa within the Shigella-E. coli complex. E. vulneris and E. hermannii showed susceptibility patterns to many antibiotics similar to Shigella and E. coli, but there were other antibiotics toward which there were significant differences in natural susceptibility. E. vulneris and E. hermannii were less susceptible to nitrofurantoin and slightly more susceptible to several aminoglycosides than E. coli and Shigella. E. hermannii was the only species that was naturally resistant/intermediate to ticarcillin and amoxycillin (DIN standard). The addition of clavulanic acid to the latter resulted in a decrease of seven twofold dilution steps (E. vulneris: four twofold dilution steps, E. coli/Shigella: two twofold dilution steps) of the MICs of the

  19. Sandwich fluorimetric method for specific detection of Staphylococcus aureus based on antibiotic-affinity strategy.

    PubMed

    Kong, Weijun; Xiong, Jie; Yue, Huan; Fu, Zhifeng

    2015-10-01

    A novel antibiotic-affinity strategy was designed for fluorimetric detection of pathogenic bacteria based on the strong affinity of antibiotic agent to the cell wall of bacteria. In this proof-of-concept work, vancocin, a glycopeptide antibiotic for Gram-positive bacteria, was used as a molecular recognition agent to anchor Staphylococcus aureus (S. aureus) cell. To improve the specificity of this method for S. aureus detection, IgG was adopted as the second recognition agent utilizing the binding between Fc region of IgG and S. aureus protein A in the cell wall, to form a sandwich complex. By using fluorescein isothiocyanate as the signal probe, S. aureus whole cells could be directly assayed within a linear range of 1.0 × 10(3)-1.0 × 10(9) CFU mL(-1) with a detection limit of 2.9 × 10(2) CFU mL(-1). The whole assay process could be completed within 130 min when a ready-for-use microplate was adopted. This proposed strategy for pathogenic bacteria detection possessed some attractive characteristics such as high sensitivity, wide linear range, simple manipulation, short assay time, and low cost. Furthermore, this sandwich mode also showed ideal specificity because vancocin and IgG bound with S. aureus at two distinct sites. It opened up a new pathway for high-throughput screening of pathogenic bacteria in medical diagnosis, food safety, bioterrorism defense, and drug discovery. PMID:26352835

  20. Ecological antibiotic policy.

    PubMed

    Høiby

    2000-08-01

    Development of resistance to antibiotics is a major problem worldwide. The normal oropharyngeal flora, the intestinal flora and the skin flora play important roles in this development. Within a few days after the onset of antibiotic therapy, resistant Escherichia coli, Haemophilus influenzae and Staphylococcus epidermidis can be detected in the normal flora of volunteers or patients. Horizontal spread of the resistance genes to other species, e.g. SALMONELLA: spp., Staphylococcus aureus and Streptococcus pneumoniae, occurs by conjugation or transformation. An ecologically sound antibiotic policy favours the use of antibiotics with little or no impact on the normal flora. Prodrug antibiotics which are not active against the bacteria in the mouth and the intestine (before absorption) and which are not excreted to a significant degree via the intestine, saliva or skin are therefore preferred. Prodrugs such as pivampicillin, bacampicillin, pivmecillinam and cefuroxime axetil are favourable from an ecological point of view. Experience from Scandinavia supports this, since resistance to mecillinam after 20 years of use is low (about 5%) and stable. PMID:10969054

  1. Ecological antibiotic policy.

    PubMed

    Høiby, N

    2000-09-01

    Development of resistance to antibiotics is a major problem worldwide. The normal oropharyngeal flora, the intestinal flora and the skin flora play important roles in this development. Within a few days after the onset of antibiotic therapy, resistant Escherichia coli, Haemophilus influenzae and Staphylococcus epidermidis can be detected in the normal flora of volunteers or patients. Horizontal spread of the resistance genes to other species, e.g. Salmonella spp., Staphylococcus aureus and Streptococcus pneumoniae, occurs by conjugation or transformation. An ecologically sound antibiotic policy favours the use of antibiotics with little or no impact on the normal flora. Prodrug antibiotics which are not active against the bacteria in the mouth and the intestine (before absorption) and which are not excreted to a significant degree via the intestine, saliva or skin are therefore preferred. Prodrugs such as pivampicillin, bacampicillin, pivmecillinam and cefuroxime axetil are favourable from an ecological point of view. Experience from Scandinavia supports this, since resistance to mecillinam after 20 years of use is low (about 5%) and stable. PMID:11051626

  2. Active Insolubilized Antibiotics Based on Cellulose-Metal Chelates1

    PubMed Central

    Kennedy, J. F.; Barker, S. A.; Zamir, A.

    1974-01-01

    Cellulose was converted into a more reactive form by chelation with the transition metals titaniumIII, ironIII, tinIV, vanadiumIII, and zirconiumIV. The remaining unsubstituted ligands of the transition metal ions were found to be amenable to replacement by electron-donating groups of antibiotic molecules. Ampicillin, gentamicin, kanamycin, neomycin, paromomycin, polymyxin B, and streptomycin were used as antibacterial antibiotics, and amphotericin B and natamycin were used as antifungal antibiotics. Antibacterial activity of the products was tested against two gram-positive and two gram-negative bacteria, and antifungal activity was tested against four fungi. That the antibacterial antibiotics had complexed with the cellulose-metal chelates was demonstrated in that the product cellulose-metal-antibiotic chelates exhibited antibiotic activities whereas the metal chelates of cellulose themselves were inactive. Of 140 tests conducted, cellulose-metal-antibiotic chelates were active in 102 cases. Since the antibiotic derivatives were water insoluble and in fact retain some of the antibacterial activities of the parent compounds, the chelation method provides a facile way of rendering cellulose surfaces, etc., resistant to microbial attack over and above that degree of protection afforded by noncovalent adsorption of the antibiotic to cellulose itself. The underlying principles of the chelation reactions involved are discussed in detail. PMID:4451349

  3. Evaluating antibiotic resistance genes in soils with applied manures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antibiotics are commonly used in livestock production to promote growth and combat disease. Recent studies have shown the potential for spread of antibiotic resistance genes (ARG) to the environment following application of livestock manures. In this study, concentrations of bacteria with ARG in soi...

  4. Extraction and detection of antibiotics in the rhizosphere metabolome

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An important mechanism of natural disease suppression is the production of antibiotics by soil microbes. Antibiotics are small organic molecules of microbial origin that at low concentrations are deleterious to the growth or metabolism of other microorganisms. Soilborne pathogens are sensitive to ma...

  5. Composting swine slurry to reduce indicators and antibiotic resistance genes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Over the last twenty years there have been considerable increases in the incidence of human infections with bacteria that are resistant to commonly used antibiotics. This has precipitated concerns about the use of antibiotics in livestock production. Composting of swine manure has several advantages...

  6. Historic perspective: Prebiotics, probiotics, and other alternatives to antibiotics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antibiotic applications in agricultural and human medical arenas have resulted in tremendous increases in food animal production and historically unprecedented gains in human health protection. Successes attributed to wide-spread antibiotic use have been accompanied by the inadvertent emergence of r...

  7. Antibiotic activity in space.

    PubMed

    Lapchine, L; Moatti, N; Gasset, G; Richoilley, G; Templier, J; Tixador, R

    1986-01-01

    Environmental factors in space exert an influence on the behaviour of bacteria, particularly on their sensitivity to antibiotics. Thus, G. Taylor and S. Zaloguev observed that bacterial samples collected on the crew during flight in the Apollo-Soyouz Test Project Mission presented higher antibiotic resistance than controls. This paper presents the results of two experiments performed in 1982 and 1985 (Cytos 2 during the French-Soviet Mission and "Antibio" in the Biorack programme of the European Space Agency). The results show an increase of antibiotic resistance in bacteria growth in flight and a modification in the structure of the cell wall. All these modifications are transitory. Two hypotheses are put forward to explain the phenomenon. PMID:3569006

  8. Cardiac toxicities of antibiotics.

    PubMed Central

    Adams, H R; Parker, J L; Durrett, L R

    1978-01-01

    Isolated heart muscle preparations are useful in the study of cardiac toxicities of drugs and environmental chemicals: such tissues allow assessment of chemical effects on heart muscle that is free from indirect in vivo influences that can mask or even accentuate cardiac responses measured in the intact animal. In the present study, left atria of guinea pigs were used to demonstrate a direct cardiac depressant effect of greater-than-therapeutic concentrations of several aminoglycoside antibiotics. The toxic effect of these antibiotics seems to be a calcium-dependent event, and may prove useful to characterize contractile responses of the heart. Other antibiotic agents can also depress cardiovascular function, as summarized in this report, but mechanisms of action have not been clearly defined. PMID:720315

  9. Direct glycan structure determination of intact N-linked glycopeptides by low-energy collision-induced dissociation tandem mass spectrometry and predicted spectral library searching.

    PubMed

    Pai, Pei-Jing; Hu, Yingwei; Lam, Henry

    2016-08-31

    Intact glycopeptide MS analysis to reveal site-specific protein glycosylation is an important frontier of proteomics. However, computational tools for analyzing MS/MS spectra of intact glycopeptides are still limited and not well-integrated into existing workflows. In this work, a new computational tool which combines the spectral library building/searching tool, SpectraST (Lam et al. Nat. Methods2008, 5, 873-875), and the glycopeptide fragmentation prediction tool, MassAnalyzer (Zhang et al. Anal. Chem.2010, 82, 10194-10202) for intact glycopeptide analysis has been developed. Specifically, this tool enables the determination of the glycan structure directly from low-energy collision-induced dissociation (CID) spectra of intact glycopeptides. Given a list of possible glycopeptide sequences as input, a sample-specific spectral library of MassAnalyzer-predicted spectra is built using SpectraST. Glycan identification from CID spectra is achieved by spectral library searching against this library, in which both m/z and intensity information of the possible fragmentation ions are taken into consideration for improved accuracy. We validated our method using a standard glycoprotein, human transferrin, and evaluated its potential to be used in site-specific glycosylation profiling of glycoprotein datasets from LC-MS/MS. In addition, we further applied our method to reveal, for the first time, the site-specific N-glycosylation profile of recombinant human acetylcholinesterase expressed in HEK293 cells. For maximum usability, SpectraST is developed as part of the Trans-Proteomic Pipeline (TPP), a freely available and open-source software suite for MS data analysis. PMID:27506355

  10. Analysis of glycoproteins in human serum by means of glycospecific magnetic bead separation and LC-MALDI-TOF/TOF analysis with automated glycopeptide detection.

    PubMed

    Sparbier, Katrin; Asperger, Arndt; Resemann, Anja; Kessler, Irina; Koch, Sonja; Wenzel, Thomas; Stein, Günter; Vorwerg, Lars; Suckau, Detlev; Kostrzewa, Markus

    2007-09-01

    Comprehensive proteomic analyses require efficient and selective pre-fractionation to facilitate analysis of post-translationally modified peptides and proteins, and automated analysis workflows enabling the detection, identification, and structural characterization of the corresponding peptide modifications. Human serum contains a high number of glycoproteins, comprising several orders of magnitude in concentration. Thereby, isolation and subsequent identification of low-abundant glycoproteins from serum is a challenging task. selective capturing of glycopeptides and -proteins was attained by means of magnetic particles specifically functionalized with lectins or boronic acids that bind to various structural motifs. Human serum was incubated with differentially functionalized magnetic micro-particles (lectins or boronic acids), and isolated proteins were digested with trypsin. Subsequently, the resulting complex mixture of peptides and glycopeptides was subjected to LC-MALDI analysis and database searching. In parallel, a second magnetic bead capturing was performed on the peptide level to separate and analyze by LC-MALDI intact glycopeptides, both peptide sequence and glycan structure. Detection of glycopeptides was achieved by means of a software algorithm that allows extraction and characterization of potential glycopeptide candidates from large LC-MALDI-MS/MS data sets, based on N-glycopeptide-specific fragmentation patterns and characteristic fragment mass peaks, respectively. By means of fast and simple glycospecific capturing applied in conjunction with extensive LC-MALDI-MS/MS analysis and novel data analysis tools, a high number of low-abundant proteins were identified, comprising known or predicted glycosylation sites. According to the specific binding preferences of the different types of beads, complementary results were obtained from the experiments using either magnetic ConA-, LCA-, WGA-, and boronic acid beads, respectively. PMID:17916798

  11. Antibiotic prophylaxis in otolaryngologic surgery

    PubMed Central

    Ottoline, Ana Carolina Xavier; Tomita, Shiro; Marques, Marise da Penha Costa; Felix, Felippe; Ferraiolo, Priscila Novaes; Laurindo, Roberta Silveira Santos

    2013-01-01

    Summary Aim: Antibiotic prophylaxis aims to prevent infection of surgical sites before contamination or infection occurs. Prolonged antibiotic prophylaxis does not enhance the prevention of surgical infection and is associated with higher rates of antibiotic-resistant microorganisms. This review of the literature concerning antibiotic prophylaxis, with an emphasis on otolaryngologic surgery, aims to develop a guide for the use of antibiotic prophylaxis in otolaryngologic surgery in order to reduce the numbers of complications stemming from the indiscriminate use of antibiotics. PMID:25991999

  12. Tackling antibiotic resistance

    PubMed Central

    Bush, Karen; Courvalin, Patrice; Dantas, Gautam; Davies, Julian; Eisenstein, Barry; Huovinen, Pentti; Jacoby, George A.; Kishony, Roy; Kreiswirth, Barry N.; Kutter, Elizabeth; Lerner, Stephen A.; Levy, Stuart; Lewis, Kim; Lomovskaya, Olga; Miller, Jeffrey H.; Mobashery, Shahriar; Piddock, Laura J. V.; Projan, Steven; Thomas, Christopher M.; Tomasz, Alexander; Tulkens, Paul M.; Walsh, Timothy R.; Watson, James D.; Witkowski, Jan; Witte, Wolfgang; Wright, Gerry; Yeh, Pamela; Zgurskaya, Helen I.

    2014-01-01

    The development and spread of antibiotic resistance in bacteria is a universal threat to both humans and animals that is generally not preventable, but can nevertheless be controlled and must be tackled in the most effective ways possible. To explore how the problem of antibiotic resistance might best be addressed, a group of thirty scientists from academia and industry gathered at the Banbury Conference Centre in Cold Spring Harbor, New York, May 16-18, 2011. From these discussions emerged a priority list of steps that need to be taken to resolve this global crisis. PMID:22048738

  13. Bioavailability of veterinary antibiotics in surface water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Veterinary antibiotics are commonly used as feed additives in livestock production for growth promotion and disease prevention. These pharmaceuticals are often excreted by the livestock in urine and feces, and enter the environment via manure application. Little is known about the fate of veterinary...

  14. Improved method for the on-line metal chelate affinity chromatography-high-performance liquid chromatographic determination of tetracycline antibiotics in animal products.

    PubMed

    Cooper, A D; Stubbings, G W; Kelly, M; Tarbin, J A; Farrington, W H; Shearer, G

    1998-07-01

    An improved on-line metal chelate affinity chromatography-high-performance liquid chromatography (MCAC-HPLC) method for the determination of tetracycline antibiotics in animal tissues and egg has been developed. Extraction was carried out with ethyl acetate. The extract was then evaporated to dryness and reconstituted in methanol prior to on-line MCAC clean-up and HPLC-UV determination. Recoveries of tetracycline, oxytetracycline, demeclocycline and chlortetracycline in the range 42% to 101% were obtained from egg, poultry, fish and venison tissues spiked at 25 micrograms kg-1. Limits of detection less than 10 microgram kg-1 were estimated for all four analytes. This method has higher throughput, higher recovery and lower limits of detection than a previously reported on-line MCAC-HPLC method which involved aqueous extraction and solid-phase extraction clean-up. PMID:9691328

  15. Feasibility study of veterinary antibiotic consumption in Germany - comparison of ADDs and UDDs by animal production type, antimicrobial class and indication

    PubMed Central

    2014-01-01

    Background Within a feasibility study the use of antibiotics in pigs and cattle was determined in 24 veterinary practices in Lower Saxony and on 66 farms in North Rhine-Westphalia in Germany. Focus was laid on the comparison of the Used Daily Doses (UDD) (dose per animal and day prescribed by the veterinarians) with the Defined Animal Daily Doses (ADD) (dose per animal and day calculated by means of recommended dosages and estimated live weights). Results For piglets and calves most of the UDD (50% and 46% of nUDD, respectively) were above the ADD (i.e. UDD/ADD-ratio above 1.25). Regarding sows, fattening pigs, dairy and beef cattle, most of the UDDs (49% to 65% of nUDD) were lower than the respective ADD (i.e. UDD/ADD-ratio below 0.8). In pigs, the UDDs of beta-lactams, fluoroquinolones and cephalosporins, and in cattle, those of macrolides and beta-lactams were often below the ADDs. Tetracyclines were frequently used above the recommended dose. Enteric diseases were more often treated below the recommended dose than respiratory diseases, possibly due to overestimation of the live weight (diarrhea in young animals, respiratory diseases in elder animals) and consequently overestimation of the recommended dose. Conclusion Comparisons between UDD and ADD can be used to observe differences between antimicrobials and trends in the usage of antibiotics. But individual treatment comparisons of UDD and ADD must be interpreted carefully, because they may be due to lower live weights than estimated. Correlating such data with data on the occurrence of resistant bacteria in future may help to improve resistance prevention and control. PMID:24401194

  16. Diversity of VanA Glycopeptide Resistance Elements in Enterococci from Humans and Nonhuman Sources

    PubMed Central

    Woodford, Neil; Adebiyi, Antoinette-Mary A.; Palepou, Marie-France I.; Cookson, Barry D.

    1998-01-01

    Elements mediating VanA glycopeptide resistance in 106 diverse enterococci from humans and nonhuman sources were compared with the prototype VanA transposon, Tn1546, in Enterococcus faecium BM4147. The isolates included 64 from individual patients at 15 hospitals in the United Kingdom (isolated between 1987 and 1996) and 42 from nonhuman sources in the United Kingdom (27 from raw meat, 7 from animal feces, and 8 from sewage). VanA elements were assigned to 24 groups (designated groups A to X) with primers that amplified 10 overlapping fragments of Tn1546. Ten groups of elements were found only in human enterococci, eight groups of elements were unique to nonhuman strains, and six groups of elements were common in enterococci from all sources. Elements indistinguishable from Tn1546 (group A) were observed more frequently in enterococci from nonhuman sources (34 versus 9%) but were identified in enterococci that caused outbreaks in hospital patients between 1987 and 1995. The most common group found in human enterococci (group H; 33%) was rarely observed in enterococci from other sources (5%). Group H elements differed from Tn1546 in three regions and included a novel insertion sequence, designated IS1542, between orf2 and vanR. The VanA elements of 14 other groups had a similar insertion at this position and/or distinct insertions at other positions. We conclude that VanA elements in enterococci are heterogeneous, although all show regions of homology with Tn1546. Furthermore, the elements most common among the human and nonhuman enterococci studied were different. This approach may be useful for monitoring the evolution of VanA resistance and may also be applicable in local “snapshot” epidemiological studies. However, as transposition events involving insertion sequences accounted for the differences observed between several groups, the stability of the elements must be assessed before their true epidemiological significance can be determined. PMID:9517923

  17. Fosfomycin plus β-Lactams as Synergistic Bactericidal Combinations for Experimental Endocarditis Due to Methicillin-Resistant and Glycopeptide-Intermediate Staphylococcus aureus

    PubMed Central

    del Río, A.; García-de-la-Mària, C.; Entenza, J. M.; Gasch, O.; Armero, Y.; Soy, D.; Mestres, C. A.; Pericás, J. M.; Falces, C.; Ninot, S.; Almela, M.; Cervera, C.; Gatell, J. M.; Moreno, A.; Moreillon, P.; Marco, F.

    2015-01-01

    The urgent need of effective therapies for methicillin-resistant Staphylococcus aureus (MRSA) infective endocarditis (IE) is a cause of concern. We aimed to ascertain the in vitro and in vivo activity of the older antibiotic fosfomycin combined with different beta-lactams against MRSA and glycopeptide-intermediate-resistant S. aureus (GISA) strains. Time-kill tests with 10 isolates showed that fosfomycin plus imipenem (FOF+IPM) was the most active evaluated combination. In an aortic valve IE model with two strains (MRSA-277H and GISA-ATCC 700788), the following intravenous regimens were compared: fosfomycin (2 g every 8 h [q8h]) plus imipenem (1 g q6h) or ceftriaxone (2 g q12h) (FOF+CRO) and vancomycin at a standard dose (VAN-SD) (1 g q12h) and a high dose (VAN-HD) (1 g q6h). Whereas a significant reduction of MRSA-227H load in the vegetations (veg) was observed with FOF+IPM compared with VAN-SD (0 [interquartile range [IQR], 0 to 1] versus 2 [IQR, 0 to 5.1] log CFU/g veg; P = 0.01), no statistical differences were found with VAN-HD. In addition, FOF+IPM sterilized more vegetations than VAN-SD (11/15 [73%] versus 5/16 [31%]; P = 0.02). The GISA-ATCC 700788 load in the vegetations was significantly lower after FOF+IPM or FOF+CRO treatment than with VAN-SD (2 [IQR, 0 to 2] and 0 [IQR, 0 to 2] versus 6.5 [IQR, 2 to 6.9] log CFU/g veg; P < 0.01). The number of sterilized vegetations after treatment with FOF+CRO was higher than after treatment with VAN-SD or VAN-HD (8/15 [53%] versus 4/20 [20%] or 4/20 [20%]; P = 0.03). To assess the effect of FOF+IPM on penicillin binding protein (PBP) synthesis, molecular studies were performed, with results showing that FOF+IPM treatment significantly decreased PBP1, PBP2 (but not PBP2a), and PBP3 synthesis. These results allow clinicians to consider the use of FOF+IPM or FOF+CRO to treat MRSA or GISA IE. PMID:26525803

  18. Fosfomycin plus β-Lactams as Synergistic Bactericidal Combinations for Experimental Endocarditis Due to Methicillin-Resistant and Glycopeptide-Intermediate Staphylococcus aureus.

    PubMed

    del Río, A; García-de-la-Mària, C; Entenza, J M; Gasch, O; Armero, Y; Soy, D; Mestres, C A; Pericás, J M; Falces, C; Ninot, S; Almela, M; Cervera, C; Gatell, J M; Moreno, A; Moreillon, P; Marco, F; Miró, J M

    2016-01-01

    The urgent need of effective therapies for methicillin-resistant Staphylococcus aureus (MRSA) infective endocarditis (IE) is a cause of concern. We aimed to ascertain the in vitro and in vivo activity of the older antibiotic fosfomycin combined with different beta-lactams against MRSA and glycopeptide-intermediate-resistant S. aureus (GISA) strains. Time-kill tests with 10 isolates showed that fosfomycin plus imipenem (FOF+IPM) was the most active evaluated combination. In an aortic valve IE model with two strains (MRSA-277H and GISA-ATCC 700788), the following intravenous regimens were compared: fosfomycin (2 g every 8 h [q8h]) plus imipenem (1 g q6h) or ceftriaxone (2 g q12h) (FOF+CRO) and vancomycin at a standard dose (VAN-SD) (1 g q12h) and a high dose (VAN-HD) (1 g q6h). Whereas a significant reduction of MRSA-227H load in the vegetations (veg) was observed with FOF+IPM compared with VAN-SD (0 [interquartile range [IQR], 0 to 1] versus 2 [IQR, 0 to 5.1] log CFU/g veg; P = 0.01), no statistical differences were found with VAN-HD. In addition, FOF+IPM sterilized more vegetations than VAN-SD (11/15 [73%] versus 5/16 [31%]; P = 0.02). The GISA-ATCC 700788 load in the vegetations was significantly lower after FOF+IPM or FOF+CRO treatment than with VAN-SD (2 [IQR, 0 to 2] and 0 [IQR, 0 to 2] versus 6.5 [IQR, 2 to 6.9] log CFU/g veg; P < 0.01). The number of sterilized vegetations after treatment with FOF+CRO was higher than after treatment with VAN-SD or VAN-HD (8/15 [53%] versus 4/20 [20%] or 4/20 [20%]; P = 0.03). To assess the effect of FOF+IPM on penicillin binding protein (PBP) synthesis, molecular studies were performed, with results showing that FOF+IPM treatment significantly decreased PBP1, PBP2 (but not PBP2a), and PBP3 synthesis. These results allow clinicians to consider the use of FOF+IPM or FOF+CRO to treat MRSA or GISA IE. PMID:26525803

  19. Differences in Antibiotic Resistance Patterns of Enterococcus faecalis and Enterococcus faecium Strains Isolated from Farm and Pet Animals

    PubMed Central

    Butaye, Patrick; Devriese, Luc A.; Haesebrouck, Freddy

    2001-01-01

    The prevalence of acquired resistance in 146 Enterococcus faecium and 166 Enterococcus faecalis strains from farm and pet animals, isolated in 1998 and 1999 in Belgium, against antibiotics used for growth promotion and for therapy was determined. Acquired resistance against flavomycin and monensin, two antibiotics used solely for growth promotion, was not detected. Avoparcin (glycopeptide) resistance was found sporadically in E. faecium only. Avilamycin resistance was almost exclusively seen in strains from farm animals. Resistance rates were higher in E. faecium strains from broiler chickens than in strains from other animal groups with tylosin and virginiamycin and in E. faecalis as well as in E. faecium strains with narasin and bacitracin. Resistance against ampicillin was mainly found among E. faecium strains from pets and was absent in E. faecalis. Tetracycline resistance occurred most often in strains from farm animals, while enrofloxacin resistance, only found in E. faecalis, occurred equally among strains from all origins. Resistance against gentamicin was very rare in broiler strains, whereas resistance rates were high in strains from other origins. It can be concluded that resistance against antibiotics used solely for growth promotion was more prevalent in E. faecium strains than in E. faecalis strains. With few exceptions, resistance against the different categories of antibiotics was more prevalent in strains from farm animals than in those from pets. PMID:11302798

  20. Differences in antibiotic resistance patterns of Enterococcus faecalis and Enterococcus faecium strains isolated from farm and pet animals.

    PubMed

    Butaye, P; Devriese, L A; Haesebrouck, F

    2001-05-01

    The prevalence of acquired resistance in 146 Enterococcus faecium and 166 Enterococcus faecalis strains from farm and pet animals, isolated in 1998 and 1999 in Belgium, against antibiotics used for growth promotion and for therapy was determined. Acquired resistance against flavomycin and monensin, two antibiotics used solely for growth promotion, was not detected. Avoparcin (glycopeptide) resistance was found sporadically in E. faecium only. Avilamycin resistance was almost exclusively seen in strains from farm animals. Resistance rates were higher in E. faecium strains from broiler chickens than in strains from other animal groups with tylosin and virginiamycin and in E. faecalis as well as in E. faecium strains with narasin and bacitracin. Resistance against ampicillin was mainly found among E. faecium strains from pets and was absent in E. faecalis. Tetracycline resistance occurred most often in strains from farm animals, while enrofloxacin resistance, only found in E. faecalis, occurred equally among strains from all origins. Resistance against gentamicin was very rare in broiler strains, whereas resistance rates were high in strains from other origins. It can be concluded that resistance against antibiotics used solely for growth promotion was more prevalent in E. faecium strains than in E. faecalis strains. With few exceptions, resistance against the different categories of antibiotics was more prevalent in strains from farm animals than in those from pets. PMID:11302798