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Sample records for class iia bacteriocins

  1. Class IIa Bacteriocins: Current Knowledge and Perspectives

    Science.gov (United States)

    Belguesmia, Yanath; Naghmouchi, Karim; Chihib, Nour-Eddine; Drider, Djamel

    Lactic acid bacteria (LAB) are known to produce antibacterial peptides and small proteins called bacteriocins, which enable them to compete against other bacteria in the environment. Bacteriocins fall structurally and chemically into three different classes, I, II, and III. Bacteriocins are ribosomally synthesized peptides with antagonism against closely related bacteria. This late observation has evolved because bacteriocins active against Gram-negative bacteria have recently been reported. Members of class IIa bacteriocins, referred to as pediocin-like bacteriocins, are among the most studied bacteriocins. This chapter is aimed at providing an updated review on the biology of class IIa bacteriocins.

  2. The Continuing Story of Class IIa Bacteriocins

    Science.gov (United States)

    Drider, Djamel; Fimland, Gunnar; Héchard, Yann; McMullen, Lynn M.; Prévost, Hervé

    2006-01-01

    Many bacteria produce antimicrobial peptides, which are also referred to as peptide bacteriocins. The class IIa bacteriocins, often designated pediocin-like bacteriocins, constitute the most dominant group of antimicrobial peptides produced by lactic acid bacteria. The bacteriocins that belong to this class are structurally related and kill target cells by membrane permeabilization. Despite their structural similarity, class IIa bacteriocins display different target cell specificities. In the search for new antibiotic substances, the class IIa bacteriocins have been identified as promising new candidates and have thus received much attention. They kill some pathogenic bacteria (e.g., Listeria) with high efficiency, and they constitute a good model system for structure-function analyses of antimicrobial peptides in general. This review focuses on class IIa bacteriocins, especially on their structure, function, mode of action, biosynthesis, bacteriocin immunity, and current food applications. The genetics and biosynthesis of class IIa bacteriocins are well understood. The bacteriocins are ribosomally synthesized with an N-terminal leader sequence, which is cleaved off upon secretion. After externalization, the class IIa bacteriocins attach to potential target cells and, through electrostatic and hydrophobic interactions, subsequently permeabilize the cell membrane of sensitive cells. Recent observations suggest that a chiral interaction and possibly the presence of a mannose permease protein on the target cell surface are required for a bacteria to be sensitive to class IIa bacteriocins. There is also substantial evidence that the C-terminal half penetrates into the target cell membrane, and it plays an important role in determining the target cell specificity of these bacteriocins. Immunity proteins protect the bacteriocin producer from the bacteriocin it secretes. The three-dimensional structures of two class IIa immunity proteins have been determined, and it has

  3. Genetic characterisation and heterologous expression of leucocin C, a class IIa bacteriocin from Leuconostoc carnosum 4010

    OpenAIRE

    Wan, Xing

    2012-01-01

    Class IIa (pediocin-like) bacteriocins are a major group of bacteriocins produced by lactic acid bacteria (LAB) characterised by their antilisterial activity. As a protective LAB strain for meat products, Leuconostoc carnosum 4010 kills Listeria by producing two class IIa bacteriocins, the well characterised leucocin A (LeuA) and the less studied leucocin C (LecC). Although the amino acid sequence of the secreted LecC has been published, the genes required for its production remain unknown. T...

  4. Role of acetate in production of an autoinducible Class IIa Bacteriocin in Carnobacterium piscicola A9b

    DEFF Research Database (Denmark)

    Nilsson, Lilian; Nielsen, Michael Krogsgaard; Ng, Yin; Gram, Lone

    2002-01-01

    Carnobacterium piscicola strain A9b isolated from cold smoked salmon inhibits growth of the food-borne pathogen Listeria monocytogenes partly due to the production of a proteinaceous compound (L. Nilsson, L. Gram, and H. H. Huss. J. Food Prot. 62:336-342, 1999). The purpose of the present study was...... on the results, carnobacteriocin B2 was used as an induction factor to manipulate the production of bacteriocin in cold smoked salmon juice and thus improve the ability to inhibit L. monocytogenes....... to purify the compound and describe factors affecting its production, with particular emphasis on food-relevant factors. Amino acid sequencing showed that the compound is a class IIa bacteriocin with an N-terminal amino acid sequence identical to that of carnobacteriocin B2. The production of the...

  5. The Two-Peptide (Class-IIb) Bacteriocins: Genetics, Biosynthesis, Structure, and Mode of Action

    Science.gov (United States)

    Nissen-Meyer, Jon; Oppegård, Camilla; Rogne, Per; Haugen, Helen Sophie; Kristiansen, Per Eugen

    The two-peptide (class-IIb) bacteriocins consist of two different peptides, both of which are required to obtain high antimicrobial activity. These bacteriocins kill target-cells by inducing membrane-leakage and they seem to display some specificity with respect to the molecules they transfer across membranes. The genes encoding the two peptides of two-peptide bacteriocins are next to each other on the same operon. In the same or a nearby operon are genes encoding (i) the immunity protein that protects the bacteriocin-producer from its own bacteriocin, (ii) a dedicated ABC-transporter that exports the bacteriocin from cells and cleaves off the N-terminal bacteriocin leader sequence, and (iii) an accessory protein whose exact function has not been fully clarified. Some two-peptide bacteriocins appear to be produced constitutively, whereas the production of other two-peptide bacteriocins is regulated through a three-component regulatory system that consists of a peptide pheromone, a membrane-associated histidine protein kinase, and response regulators. It has recently been proposed that the two peptides of (some) two-peptide bacteriocins may form a membrane-penetrating helix-helix structure involving helix-helix interacting GxxxG-motifs present in all currently characterized two-peptide bacteriocins. It has also been suggested that the helix-helix structure interacts with an integrated membrane (transport) protein, thus inducing a conformational change in the protein, which in turn causes membrane-leakage. This proposed mode-of-action is similar to that of the pediocin-like (class-IIa) bacteriocins and lactococcin A, which bind to a part of the mannose phosphotransferase permease that is embedded in the cell membrane, thereby altering the conformation of the ­permease in a manner that causes membrane-leakage and cell death.

  6. Class IId or Linear and Non-Pediocin-Like Bacteriocins

    Science.gov (United States)

    Iwatani, Shun; Zendo, Takeshi; Sonomoto, Kenji

    Class IId bacteriocins are one of the subclasses of class II bacteriocins produced by lactic acid bacteria. This class of bacteriocins, however, show a great diversity in their primary structures and modes of action. This chapter focuses on two aspects: (1) the description of those heterogeneous bacteriocins with the concept of three potential subgroups and (2) the modes of action of lactococcin A, lactococcin 972, and lacticin Q, each of which belongs to a different subgroup and is well characterized in its unique mode of action.

  7. Pediocins: The bacteriocins of Pediococci. Sources, production, properties and applications

    OpenAIRE

    Anastasiadou Sofia; Papagianni Maria

    2009-01-01

    Abstract Class IIa bacteriocins from lactic acid bacteria are small, cationic proteins with antilisterial activity. Within this class, the pediocins are those bacteriocins that share a highly conserved hydrophilic and charged N-terminal part harboring the consensus sequence -YGNGV- and a more variable hydrophobic and/or amphiphilic C-terminal part. Several pediocins have been isolated and characterized. Despite the structural similarities, their molecular weight varies, as well as their spect...

  8. Class IIa histone deacetylases are hormone-activated regulators of FOXO and mammalian glucose homeostasis

    DEFF Research Database (Denmark)

    Mihaylova, Maria M; Vasquez, Debbie S; Ravnskjær, Kim;

    2011-01-01

    Class IIa histone deacetylases (HDACs) are signal-dependent modulators of transcription with established roles in muscle differentiation and neuronal survival. We show here that in liver, class IIa HDACs (HDAC4, 5, and 7) are phosphorylated and excluded from the nucleus by AMPK family kinases. In...... response to the fasting hormone glucagon, class IIa HDACs are rapidly dephosphorylated and translocated to the nucleus where they associate with the promoters of gluconeogenic enzymes such as G6Pase. In turn, HDAC4/5 recruit HDAC3, which results in the acute transcriptional induction of these genes via...... deacetylation and activation of FOXO family transcription factors. Loss of class IIa HDACs in murine liver results in inhibition of FOXO target genes and lowers blood glucose, resulting in increased glycogen storage. Finally, suppression of class IIa HDACs in mouse models of type 2 diabetes ameliorates...

  9. Complete genome sequence of Lactobacillus paraplantarum L-ZS9, a probiotic starter producing class II bacteriocins.

    Science.gov (United States)

    Liu, Lei; Li, Pinglan

    2016-03-20

    Lactobacillus paraplantarum L-ZS9 is a probiotic starter isolated from fermented sausage and it is a great producer of class II bacteriocins. To the best of our knowledge, this is the first complete sequenced genome of L. paraplantarum deposited in GenBank database. The size of the complete genome of L. paraplantarum L-ZS9 is 3,139,729bp. The genomic sequence revealed that this strain includes 19 genes involved in class II bacteriocins production and regulation. The information fill the gaps of the L. paraplantarum genome information and contribute to the improvement of class II bacteriocins research. PMID:26853479

  10. The structure of pyogenecin immunity protein, a novel bacteriocin-like immunity protein from streptococcus pyogenes.

    Energy Technology Data Exchange (ETDEWEB)

    Chang, C.; Coggill, P.; Bateman, A.; Finn, R.; Cymborowski, M.; Otwinowski, Z.; Minor, W.; Volkart, L.; Joachimiak, A.; Wellcome Trust Sanger Inst.; Univ. of Virginia; UT Southwestern Medical Center

    2009-12-17

    Many Gram-positive lactic acid bacteria (LAB) produce anti-bacterial peptides and small proteins called bacteriocins, which enable them to compete against other bacteria in the environment. These peptides fall structurally into three different classes, I, II, III, with class IIa being pediocin-like single entities and class IIb being two-peptide bacteriocins. Self-protective cognate immunity proteins are usually co-transcribed with these toxins. Several examples of cognates for IIa have already been solved structurally. Streptococcus pyogenes, closely related to LAB, is one of the most common human pathogens, so knowledge of how it competes against other LAB species is likely to prove invaluable. We have solved the crystal structure of the gene-product of locus Spy-2152 from S. pyogenes, (PDB: 2fu2), and found it to comprise an anti-parallel four-helix bundle that is structurally similar to other bacteriocin immunity proteins. Sequence analyses indicate this protein to be a possible immunity protein protective against class IIa or IIb bacteriocins. However, given that S. pyogenes appears to lack any IIa pediocin-like proteins but does possess class IIb bacteriocins, we suggest this protein confers immunity to IIb-like peptides. Combined structural, genomic and proteomic analyses have allowed the identification and in silico characterization of a new putative immunity protein from S. pyogenes, possibly the first structure of an immunity protein protective against potential class IIb two-peptide bacteriocins. We have named the two pairs of putative bacteriocins found in S. pyogenes pyogenecin 1, 2, 3 and 4.

  11. Bacteriocins synthesized by Bacillus thuringiensis: generalities and potential applications

    Science.gov (United States)

    Salazar-Marroquín, Elma Laura; Galán-Wong, Luis J.; Moreno-Medina, Víctor Ricardo; Reyes-López, Miguel Ángel; Pereyra-Alférez, Benito

    2016-01-01

    The members of the Bacillus thuringiensis group, commonly known as Bt, produce a huge number of metabolites, which show biocidal and antagonistic activity. B. thuringiensis is widely known for synthesizing Cry, Vip and Cyt proteins, active against insects and other parasporins with biocidal activity against certain types of cancerous cells. Nevertheless, B. thuringiensis also synthesizes compounds with antimicrobial activity, especially bacteriocins. Some B. thuringiensis bacteriocins resemble lantibiotics and other small linear peptides (class IIa) from the lactic acid bacteria bacteriocins classification system. Although many bacteriocins produced by Bt have been reported, there is no proper classification for them. In this work, we have grouped these based on molecular weight and functionality. Bacteriocins are small peptides synthesized by bacteria, presenting inhibitory activity against Gram-positive and Gram-negative bacteria and to a lesser extent against fungi. These molecules represent a good study model in the search for microbial control alternatives. Lactic acid bacteria produces a huge number of these types of molecules with great potential. Nonetheless, members of the Bacillus, cereus group, especially B. thuringiensis, emerge as an attractive alternative for obtaining bacteriocins showing novel activities. This review describes the potential applications of B. thuringiensis bacteriocins in the control of foodborne pathogens, environment and medical area. PMID:27340340

  12. Class IIa histone deacetylases affect neuronal remodeling and functional outcome after stroke.

    Science.gov (United States)

    Kassis, Haifa; Shehadah, Amjad; Li, Chao; Zhang, Yi; Cui, Yisheng; Roberts, Cynthia; Sadry, Neema; Liu, Xianshuang; Chopp, Michael; Zhang, Zheng Gang

    2016-06-01

    We have previously demonstrated that stroke induces nuclear shuttling of class IIa histone deacetylase 4 (HDAC4). Stroke-induced nuclear shuttling of HDAC4 is positively and significantly correlated with improved indices of neuronal remodeling in the peri-infarct cortex. In this study, using a rat model for middle cerebral artery occlusion (MCAO), we tested the effects of selective inhibition of class IIa HDACs on functional recovery and neuronal remodeling when administered 24hr after stroke. Adult male Wistar rats (n = 15-17/group) were subjected to 2 h MCAO and orally gavaged with MC1568 (a selective class IIa HDAC inhibitor), SAHA (a non-selective HDAC inhibitor), or vehicle-control for 7 days starting 24 h after MCAO. A battery of behavioral tests was performed. Lesion volume measurement and immunohistochemistry were performed 28 days after MCAO. We found that stroke increased total HDAC activity in the ipsilateral hemisphere compared to the contralateral hemisphere. Stroke-increased HDAC activity was significantly decreased by the administration of SAHA as well as by MC1568. However, SAHA significantly improved functional outcome compared to vehicle control, whereas selective class IIa inhibition with MC1568 increased mortality and lesion volume and did not improve functional outcome. In addition, MC1568 decreased microtubule associated protein 2 (MAP2, dendrites), phosphorylated neurofilament heavy chain (pNFH, axons) and myelin basic protein (MBP, myelination) immunoreactivity in the peri-infarct cortex. Quantitative RT-PCR of cortical neurons isolated by laser capture microdissection revealed that MC1568, but not SAHA, downregulated CREB and c-fos expression. Additionally, MC1568 decreased the expression of phosphorylated CREB (active) in neurons. Taken together, these findings demonstrate that selective inhibition of class IIa HDACs impairs neuronal remodeling and neurological outcome. Inactivation of CREB and c-fos by MC1568 likely contributes to

  13. Pediocin PA-1, a wide-spectrum bacteriocin from lactic acid bacteria

    NARCIS (Netherlands)

    Rodriguez, JM; Martinez, MI; Kok, J

    2002-01-01

    Pediocin PA-1 is a broad-spectrum lactic acid bacteria bacteriocin that shows a particularly strong activity against Listeria monocytogenes, a foodborne pathogen of special concern among the food industries. This antimicrobial peptide is the most extensively studied class IIa (or pediocin family) ba

  14. 14-3-3 regulates the nuclear import of class IIa histone deacetylases

    International Nuclear Information System (INIS)

    Class IIa histone deacetylases (HDACs) form complexes with a class of transcriptional repressors in the nucleus. While screening for compounds that could block the association of HDAC4 with the BTB domain-containing transcriptional repressor Bach2, we discovered that phorbol 12-myristate 13-acetate (PMA) induced the cytoplasmic retention of HDAC4 mutants lacking a nuclear export signal (NES). Although PMA treatment and PKD overexpression has been proposed to facilitate the nuclear export of class IIa HDACs by creating 14-3-3 binding sites containing phosphoserines, our experiments using HDAC mutants demonstrated that PMA greatly reduces nuclear import. PMA treatment repressed the NLS activity in a manner dependent on 14-3-3 binding. These results suggest that nuclear HDAC4 is not tethered in the nucleus, but instead shuttles between the nucleus and the cytoplasm. Phosphorylation-induced 14-3-3 binding biases the balance of nucleo-cytoplasmic shuttling toward the cytoplasm by inhibiting nuclear import.

  15. Roles and post-translational regulation of cardiac class IIa histone deacetylase isoforms.

    Science.gov (United States)

    Weeks, Kate L; Avkiran, Metin

    2015-04-15

    Cardiomyocyte hypertrophy is an integral component of pathological cardiac remodelling in response to mechanical and chemical stresses in settings such as chronic hypertension or myocardial infarction. For hypertrophy to ensue, the pertinent mechanical and chemical signals need to be transmitted from membrane sensors (such as receptors for neurohormonal mediators) to the cardiomyocyte nucleus, leading to altered transcription of the genes that regulate cell growth. In recent years, nuclear histone deacetylases (HDACs) have attracted considerable attention as signal-responsive, distal regulators of the transcriptional reprogramming that in turn precipitates cardiomyocyte hypertrophy, with particular focus on the role of members of the class IIa family, such as HDAC4 and HDAC5. These histone deacetylase isoforms appear to repress cardiomyocyte hypertrophy through mechanisms that involve protein interactions in the cardiomyocyte nucleus, particularly with pro-hypertrophic transcription factors, rather than via histone deacetylation. In contrast, evidence indicates that class I HDACs promote cardiomyocyte hypertrophy through mechanisms that are dependent on their enzymatic activity and thus sensitive to pharmacological HDAC inhibitors. Although considerable progress has been made in understanding the roles of post-translational modifications (PTMs) such as phosphorylation, oxidation and proteolytic cleavage in regulating class IIa HDAC localisation and function, more work is required to explore the contributions of other PTMs, such as ubiquitination and sumoylation, as well as potential cross-regulatory interactions between distinct PTMs and between class IIa and class I HDAC isoforms. PMID:25362149

  16. Isolation and Characterization of Plantaricin Produced by Lactobacillus plantarum Strains (IIA-1A5, IIA-1B1, IIA-2B2

    Directory of Open Access Journals (Sweden)

    I. I. Arief

    2013-08-01

    Full Text Available Bacteriocins produced by Indonesian lactic acid bacteria Lactobacillus plantarum IIA-1A5, IIA-1B1, IIA-2B2 were purified and characterized. Plantaricin W gene had been successfully amplified from all strains. This amplicon showed the expected 200 bp size of plantaricin W gene. This bacteriocins purified from L. plantarum IIA-1A5, IIA-1B1, and IIA-2B2 were named plantaricin IIA-1A5, IIA-1B1, and IIA-2B2. Purification by cation exchange chromatography increased the purity (fold and activity of plantaricins. Purity of plantaricin IIA-1A5 was increased by 3.13 fold with specific activity 13.40 AU/mg. Plantaricin IIA-1B1 had 2.98 fold purity with specific activity 5.12 AU/mg, while purity of plantaricin IIA-2B2 was 1.37 fold with specific activity 7.70 AU/mg. All plantaricins could inhibit the growth of pathogenic bacteria, such as Escherichia coli, Salmonella typhimurium, Bacillus cereus, and Staphylococcus aureus. Plantaricins could be digested by trypsin. Stability of plantaricins at 80 oC for 30 min and at 121 oC for 15 min were affected by type of plantaricin and species of pathogenic bacteria. Generally, plantaricin IIA-1A5 was better as antimicrobial agent than plantaricin IIA-1B1 and plantaricin IIA-2B2.

  17. Pediocin-like antimicrobial peptides (class IIa bacteriocins) and their immunity proteins: biosynthesis, structure, and mode of action.

    Science.gov (United States)

    Fimland, Gunnar; Johnsen, Line; Dalhus, Bjørn; Nissen-Meyer, Jon

    2005-11-01

    Pediocin-like antimicrobial peptides (AMPs) form a group of lactic acid bacteria produced, cationic membrane-permeabilizing peptides with 37 to 48 residues. Upon exposure to membrane-mimicking entities, their hydrophilic, cationic, and highly conserved N-terminal region forms a three-stranded antiparallel beta-sheet supported by a conserved disulfide bridge. This N-terminal beta-sheet region is followed by a central amphiphilic alpha-helix and this in most (if not all) of these peptides is followed by a rather extended C-terminal tail that folds back onto the central alpha-helix, thereby creating a hairpin-like structure in the C-terminal half. There is a flexible hinge between the beta-sheet N-terminal region and the hairpin C-terminal region and one thus obtains two domains that may move relative to each other. The cationic N-terminal beta-sheet domain mediates binding of the pediocin-like AMPs to the target-cell surface through electrostatic interactions, while the more hydrophobic and amphiphilic C-terminal hairpin domain penetrates into the hydrophobic part of the target-cell membrane, thereby mediating leakage through the membrane. The hinge provides the structural flexibility that enables the C-terminal hairpin domain to dip into the hydrophobic part of the membrane. Despite extensive sequence similarities, these AMPs differ markedly in their target-cell specificity, and results obtained with hybrid AMPs indicate that the membrane-penetrating hairpin-like C-terminal domain is the major specificity determinant. Bacteria that produce pediocin-like AMPs also produce a 11-kDa cognate immunity protein that protects the producer. The immunity proteins are well-structured, 4-helix bundle cytosolic proteins. They show a high degree of specificity in that they largely recognize and confer immunity only to their cognate AMP and in some cases to a few AMPs that are closely related to their cognate AMP. The C-terminal half of the immunity proteins contains a domain that is involved in specific recognition of the C-terminal membrane-penetrating specificity-determining hairpin domain of the cognate AMP. PMID:16059970

  18. Pediocins: The bacteriocins of Pediococci. Sources, production, properties and applications

    Directory of Open Access Journals (Sweden)

    Anastasiadou Sofia

    2009-01-01

    Full Text Available Abstract Class IIa bacteriocins from lactic acid bacteria are small, cationic proteins with antilisterial activity. Within this class, the pediocins are those bacteriocins that share a highly conserved hydrophilic and charged N-terminal part harboring the consensus sequence -YGNGV- and a more variable hydrophobic and/or amphiphilic C-terminal part. Several pediocins have been isolated and characterized. Despite the structural similarities, their molecular weight varies, as well as their spectrum of antimicrobial activity. They exhibit important technological properties, e.g. thermostability and retaining of activity at a wide pH range, which along with the bactericidal action against Gram-positive food spoilage and pathogenic bacteria, make them an important class of biopreservatives. Much new information regarding the pediocins has emerged during the last years. In this review, we summarize and discuss all the available information regarding the sources of pediocins, the characteristics of their biosynthesis and production in fermentation systems, the characteristics of the known pediocin molecules, and their antibacterial action. The advances made by genetic engineering in improving the features of pediocins are also discussed, as well as their perspectives for future applications.

  19. Pediocins: The bacteriocins of Pediococci. Sources, production, properties and applications.

    Science.gov (United States)

    Papagianni, Maria; Anastasiadou, Sofia

    2009-01-01

    Class IIa bacteriocins from lactic acid bacteria are small, cationic proteins with antilisterial activity. Within this class, the pediocins are those bacteriocins that share a highly conserved hydrophilic and charged N-terminal part harboring the consensus sequence -YGNGV- and a more variable hydrophobic and/or amphiphilic C-terminal part. Several pediocins have been isolated and characterized. Despite the structural similarities, their molecular weight varies, as well as their spectrum of antimicrobial activity. They exhibit important technological properties, e.g. thermostability and retaining of activity at a wide pH range, which along with the bactericidal action against Gram-positive food spoilage and pathogenic bacteria, make them an important class of biopreservatives. Much new information regarding the pediocins has emerged during the last years. In this review, we summarize and discuss all the available information regarding the sources of pediocins, the characteristics of their biosynthesis and production in fermentation systems, the characteristics of the known pediocin molecules, and their antibacterial action. The advances made by genetic engineering in improving the features of pediocins are also discussed, as well as their perspectives for future applications. PMID:19133115

  20. Characterization of 40 full-length MHC class IIA functional alleles in miiuy croaker: Polymorphism and positive selection.

    Science.gov (United States)

    Xu, Tianjun; Liu, Jiang; Sun, Yueyan; Zhu, Zhihuang; Liu, Tianxing

    2016-02-01

    The major histocompatibility complex is a highly polymorphic gene superfamily in vertebrates that plays an important role in adaptive immune response. In the present study, we identified 40 full-length miiuy croaker MHC class IIA (Mimi-DAA) functional alleles from 26 miiuy croaker individuals and found that the alleles encode 30 amino acid sequences. A high level of polymorphism in Mimi-DAA was detected in miiuy croaker. The rate of non-synonymous substitutions (d(N)) occurred at a significantly higher frequency than that of synonymous substitutions (d(S)) in the peptide-binding region (PBR) and non-PBR. This result suggests that balancing selection maintains polymorphisms at the Mimi-DAA locus. Phylogenetic analysis based on the full-length sequences showed that the Mimi-DAA alleles clustered into three groups. However, the phylogenetic tree constructed using the exon 2 sequences indicated that the Mimi-DAA alleles clustered into two groups. A total of 22 positively selected sites were identified on the Mimi-DAA alleles after testing for positive selection, and five sites were predicted to be associated with the binding of peptide antigen, suggesting that a few selected residues may play a significant role in immune function. PMID:26598111

  1. pbp2229-Mediated Nisin Resistance Mechanism in Listeria monocytogenes Confers Cross-Protection to Class IIa Bacteriocins and Affects Virulence Gene Expression

    OpenAIRE

    Gravesen, Anne; Kallipolitis, Birgitte; Holmstrøm, Kim; Høiby, Poul Erik; Ramnath, Manilduth; Knøchel, Susanne

    2004-01-01

    It was previously shown that enhanced nisin resistance in some mutants was associated with increased expression of three genes, pbp2229, hpk1021, and lmo2487, encoding a penicillin-binding protein, a histidine kinase, and a protein of unknown function, respectively. In the present work, we determined the direct role of the three genes in nisin resistance. Interruption of pbp2229 and hpk1021 eliminated the nisin resistance phenotype. Interruption of hpk1021 additionally abolished the increase ...

  2. Active Site Loop Dynamics of a Class IIa Fructose 1,6-Bisphosphate Aldolase from Mycobacterium tuberculosis

    Energy Technology Data Exchange (ETDEWEB)

    Pegan, Scott D. [Univ. of Denver, CO (United States); Rukseree, Kamolchanok [National Center for Genetic Engineering and Biotechnology (BIOTEC), Tha Khlong (Thailand); Capodagli, Glenn C. [Univ. of Denver, CO (United States); Baker, Erica A. [Univ. of Denver, CO (United States); Krasnykh, Olga [Univ. of Illinois, Chicago, IL (United States); Franzblau, Scott G. [Univ. of Illinois, Chicago, IL (United States); Mesecar, Andrew D. [Purdue Univ., West Lafayette, IN (United States)

    2013-01-08

    The class II fructose 1,6-bisphosphate aldolases (FBAs, EC 4.1.2.13) comprises one of two families of aldolases. Instead of forming a Schiff base intermediate using an ε-amino group of a lysine side chain, class II FBAs utilize Zn(II) to stabilize a proposed hydroxyenolate intermediate (HEI) in the reversible cleavage of fructose 1,6-bisphosphate, forming glyceraldehyde 3-phosphate and dihydroxyacetone phosphate (DHAP). As class II FBAs have been shown to be essential in pathogenic bacteria, focus has been placed on these enzymes as potential antibacterial targets. Although structural studies of class II FBAs from Mycobacterium tuberculosis (MtFBA), other bacteria, and protozoa have been reported, the structure of the active site loop responsible for catalyzing the protonation–deprotonation steps of the reaction for class II FBAs has not yet been observed. We therefore utilized the potent class II FBA inhibitor phosphoglycolohydroxamate (PGH) as a mimic of the HEI- and DHAP-bound form of the enzyme and determined the X-ray structure of the MtFBA–PGH complex to 1.58 Å. Remarkably, we are able to observe well-defined electron density for the previously elusive active site loop of MtFBA trapped in a catalytically competent orientation. Utilization of this structural information and site-directed mutagenesis and kinetic studies conducted on a series of residues within the active site loop revealed that E169 facilitates a water-mediated deprotonation–protonation step of the MtFBA reaction mechanism. Furthermore, solvent isotope effects on MtFBA and catalytically relevant mutants were used to probe the effect of loop flexibility on catalytic efficiency. Additionally, we also reveal the structure of MtFBA in its holoenzyme form.

  3. Bacteriocin small of Rhizobium leguminosarum belongs to the class of N-acyl-L-homoserine lactone molecules, known as autoinducers and as quorum sensing co-transcription factors.

    Science.gov (United States)

    Schripsema, J; de Rudder, K E; van Vliet, T B; Lankhorst, P P; de Vroom, E; Kijne, J W; van Brussel, A A

    1996-01-01

    Small bacteriocin was isolated from the culture broth of the gram-negative bacterium Rhizobium leguminosarum, which forms symbiotic nitrogen-fixing root nodules on a number of leguminous plants. The structure of the molecule was elucidated by spectroscopic methods and identified as N-(3R-hydroxy-7-cis-tetradecanoyl)-L-homoserine lactone. The absolute configuration of both asymmetric carbon atoms in the molecule was determined by the use of the chiral solvating agents S-(+)- and R-(-)-2,2,2-trifluoro-1-(9-anthryl)-ethanol. small bacteriocin is structurally related to the quorum sensing co-transcription factors for genes from other bacteria such as Vibrio fischeri, Pseudomonas aeruginosa, Erwinia carotovora, and Agrobacterium tumefaciens which are involved in animal-microbe or plant-microbe interactions. The mechanism of regulation of such interactions by this kind of co-transcription factors is still unknown in R. leguminosarum. PMID:8550454

  4. Bacteriocin Production: a Probiotic Trait?

    OpenAIRE

    Dobson, Alleson; Cotter, Paul D.; Ross, R. Paul; Hill, Colin

    2012-01-01

    Bacteriocins are an abundant and diverse group of ribosomally synthesized antimicrobial peptides produced by bacteria and archaea. Traditionally, bacteriocin production has been considered an important trait in the selection of probiotic strains, but until recently, few studies have definitively demonstrated the impact of bacteriocin production on the ability of a strain to compete within complex microbial communities and/or positively influence the health of the host. Although research in th...

  5. Gassericin A: a circular bacteriocin produced by lactic acid bacteria Lactobacillus gasseri.

    Science.gov (United States)

    Pandey, Neha; Malik, R K; Kaushik, J K; Singroha, Garima

    2013-11-01

    During the recent years extensive efforts have been made to find out bacteriocins from lactic acid bacteria (LAB) active against various food spoilage and pathogenic bacteria, and superior stabilities against heat treatments and pH variations. Bacteriocins isolated from LAB have been grouped into four classes. Circular bacteriocins which were earlier grouped among the four groups of bacteriocins, have recently been proposed to be classified into a different class, making it class V bacteriocins. Circular bacteriocins are special molecules, whose precursors must be post translationally modified to join the N to C termini with a head-to-tail peptide bond. Cyclization appears to make them less susceptible to proteolytic cleavage, high temperature and pH, and, therefore, provides enhanced stability as compared to linear bacteriocins. The advantages of circularization are also reflected by the fact that a significant number of macrocyclic natural products have found pharmaceutical applications. Circular bacteriocins were unknown two decades ago, and even to date, only a few circular bacteriocins from a diverse group of Gram positive organisms have been reported. The first example of a circular bacteriocin was enterocin AS-48, produced by Enterococcus faecalis AS-48. Gassereccin A, produced by Lactobacillus gasseri LA39, Reutericin 6 produced by Lactobacillus reuteri LA6 and Circularin A, produced by Clostridium beijerinickii ATCC 25,752, are further examples of this group of antimicrobial peptides. In the present scenario, Gassericin A can be an important tool in the food preservation owing to its properties of high pH and temperature tolerance and the fact that it is produced by LAB L. gasseri, whose many strains are proven probiotic. PMID:23712477

  6. Bacteriocins: safe, natural antimicrobials for food preservation.

    Science.gov (United States)

    Cleveland, J; Montville, T J; Nes, I F; Chikindas, M L

    2001-12-01

    Bacteriocins are antibacterial proteins produced by bacteria that kill or inhibit the growth of other bacteria. Many lactic acid bacteria (LAB) produce a high diversity of different bacteriocins. Though these bacteriocins are produced by LAB found in numerous fermented and non-fermented foods, nisin is currently the only bacteriocin widely used as a food preservative. Many bacteriocins have been characterized biochemically and genetically, and though there is a basic understanding of their structure-function, biosynthesis, and mode of action, many aspects of these compounds are still unknown. This article gives an overview of bacteriocin applications, and differentiates bacteriocins from antibiotics. A comparison of the synthesis. mode of action, resistance and safety of the two types of molecules is covered. Toxicity data exist for only a few bacteriocins, but research and their long-time intentional use strongly suggest that bacteriocins can be safely used. PMID:11764886

  7. Using Bacteriocins in Milk and Dairy Products

    Directory of Open Access Journals (Sweden)

    Evrim Güneş Altuntaş

    2010-01-01

    Full Text Available Bacteriocins produced by bacteria are ribosomally synthesed and antimicrobial peptides. Lots of strains of bacteria can produce bacteriocin. There are lots of researchs on using bacteriocins produced by lactic acid bacteria (LAB which are known as safe (GRAS in foods. With this respect bacteriocin experiments have been generally in meat and dairy products where can become spoilage easily. It is allowed to use nisin in cheese a dairy product, and with cheese the experiments about using nisin, pediocin, lacticin, variacin etc. are going on the other dairy products. In this review some experiments on using bacteriocins and their results on milk and dairy products are reported.

  8. Application of Antimicrobial Agents Produced by Lactobacillus plantarum IIA-1A5 as Natural Preservative on Beef during Room Temperature Storage

    Directory of Open Access Journals (Sweden)

    Dewi Elfrida Sihombing

    2015-05-01

    Full Text Available Lactobacillus plantarum IIA-1A5 is indigenous lactic acid bacteria isolated from Indonesian beef. Lactobacillus plantarum IIA-1A5 was reported could produce bacteriocin, called plantaricin IIA-1A5. The aims of this research was to analyze application of plantaricin IIA-1A5 as a natural preservative on beef. Based on antagonistic test, plantaricin IIA-1A5 had good moderate antimicrobial activity against pathogenic bacteria isolated from human’s feces that cause diarrhea such as Salmonella 38, Enteropathogenic Escherichia coli K11 and Shigella A33. Application of plantaricin IIA-1A5 was effective as a natural preservative on beef stored at room temperature by inhibiting the growth of Escherichia coli and Staphylococcus aureus. Plantaricin IIA-1A5 could kill all of the Escherichia coli after 5 h storage. Plantaricin IIA-1A5 could reduce the population of Staphylococcus aureus in beef during room temperature storage. Interestingly, plantaricin produced by Lactobacillus plantarum IIA-1A5 was effective against gram negative and positive bacteria. According to physichochemichal and microbiology quality, plantaricin IIA-1A5 was recommended as biopreservative agents for beef.

  9. Natural and Heterologous Production of Bacteriocins

    Science.gov (United States)

    Cintas, Luis M.; Herranz, Carmen; Hernández, Pablo E.

    Bacteriocins are ribosomally synthesized antimicrobial peptides produced by bacteria, and their use as natural and nontoxic food preservatives has been the source of considerable interest for the research community. In addition, bacteriocins have been investigated for their potential use in human and veterinary applications and in the animal production field. In the native bacterial strain, most bacteriocins are synthesized as biologically inactive precursors, with N-terminal extensions, that are cleaved concomitantly during export of the bacteriocin by dedicated ABC transporters, or the general secretory pathway (GSP) or Sec-dependent pathway. However, a few bacteriocins are synthesized without an N-terminal extension, and others are circularized through a head-to-tail peptide bond, complicating the elucidation of their processing and transport across the cytoplasmic membrane. The high cost of synthetic bacteriocin synthesis and their low yields from many natural producers recommends the exploration of recombinant microbial systems for the heterologous production of bacteriocins. Other advantages of such systems include production of bacteriocins in safer hosts, increased bacteriocin production, control of bacteriocin gene expression, production of food ingredients with antimicrobial activity, construction of multibacteriocinogenic strains with a wider antagonistic spectrum, a better adaptation of the selected hosts to food environments, and providing antagonistic properties to lactic acid bacteria (LAB) used as starter, protective, or probiotic cultures. The recombinant production of bacteriocins mostly relies on the use of expression vectors that replicate in Gram-negative bacteria, Gram-positive bacteria, and yeasts, whereas the production of bacteriocins in heterologous LAB hosts may be essentially based on the expression of native biosynthetic genes, by exchanging or replacing leader peptides and/or dedicated processing and secretion systems (ABC transporters

  10. Supersymmetric geometries of IIA supergravity III

    CERN Document Server

    Gran, Ulf; von Schultz, Christian

    2016-01-01

    We find that (massive) IIA backgrounds that admit a $G_2\\ltimes \\mathbb{R}^8$ invariant Killing spinor must exhibit a null Killing vector field which leaves the Killing spinor invariant and that the rotation of the Killing vector field satisfies a certain $\\mathfrak{g}_2$ instanton condition. This result together with those in [4] and [5] complete the classification of geometries of all (massive) IIA backgrounds that preserve one supersymmetry. We also explore the geometry of a class of backgrounds which admit a $G_2\\ltimes \\mathbb{R}^8$ invariant Killing spinor and where in addition an appropriate 1-form bilinear vanishes. In all cases, we express the fluxes of the theory in terms of the geometry.

  11. Potential of Lactic Streptococci to Produce Bacteriocin

    OpenAIRE

    Geis, Arnold; Singh, Jasjit; Teuber, Michael

    1983-01-01

    A survey was made on the bacteriocin-producing potential of lactic streptococci. Bacteriocin-like activities were isolated and partially purified from about 5% of the 280 strains investigated. The frequency of production varied from about 1% in Streptococcus lactis subsp. diacetylactis to 9 and 7.5% in S. lactis and Streptococcus cremoris, respectively. Eight strains of S. cremoris produced bacteriocins which, on the basis of heat stability at different pH values and inhibitory spectrum, coul...

  12. Bacteriocin-based strategies for food biopreservation.

    Science.gov (United States)

    Gálvez, Antonio; Abriouel, Hikmate; López, Rosario Lucas; Ben Omar, Nabil

    2007-11-30

    Bacteriocins are ribosomally-synthesized peptides or proteins with antimicrobial activity, produced by different groups of bacteria. Many lactic acid bacteria (LAB) produce bacteriocins with rather broad spectra of inhibition. Several LAB bacteriocins offer potential applications in food preservation, and the use of bacteriocins in the food industry can help to reduce the addition of chemical preservatives as well as the intensity of heat treatments, resulting in foods which are more naturally preserved and richer in organoleptic and nutritional properties. This can be an alternative to satisfy the increasing consumers demands for safe, fresh-tasting, ready-to-eat, minimally-processed foods and also to develop "novel" food products (e.g. less acidic, or with a lower salt content). In addition to the available commercial preparations of nisin and pediocin PA-1/AcH, other bacteriocins (like for example lacticin 3147, enterocin AS-48 or variacin) also offer promising perspectives. Broad-spectrum bacteriocins present potential wider uses, while narrow-spectrum bacteriocins can be used more specifically to selectively inhibit certain high-risk bacteria in foods like Listeria monocytogenes without affecting harmless microbiota. Bacteriocins can be added to foods in the form of concentrated preparations as food preservatives, shelf-life extenders, additives or ingredients, or they can be produced in situ by bacteriocinogenic starters, adjunct or protective cultures. Immobilized bacteriocins can also find application for development of bioactive food packaging. In recent years, application of bacteriocins as part of hurdle technology has gained great attention. Several bacteriocins show additive or synergistic effects when used in combination with other antimicrobial agents, including chemical preservatives, natural phenolic compounds, as well as other antimicrobial proteins. This, as well as the combined use of different bacteriocins may also be an attractive approach to

  13. Bacteriocin producers from traditional food products

    Directory of Open Access Journals (Sweden)

    Thonart P.

    2007-01-01

    Full Text Available A total of 220 strains of LAB isolated from 32 samples of traditional fermented food from Senegal were screened for bacteriocin production. Two bacteriocin producers, Lactococcus lactis subsp. lactis and Enterococcus faecium, were identified from 12 bacteriocin-producing isolates on the basis of phenotypic analyses and 16S rDNA sequence. Both bacteriocins produced by new isolates show antimicrobial activity against Listeria monocytogenes and Bacillus coagulans whereas only that produced by Lactococcus lactis has an activity against Bacillus cereus. Bacteriocin-producing Lactococcus lactis strains were found in a variety of traditional foods indicating a high potential of growth of this strain in variable ecological complex environment. Partial 16S rDNA of the two bacteriocin producers obtained in this study has been registered to Genbank databases under the accession number AY971748 for Lactococcus lactis subsp. lactis (named CWBI-B1410 and AY971749 for Enterococcus faecium (named CWBI-B1411. The new bacteriocin-producing Lactococcus lactis subsp. lactis strain has been selected for identification and application of the bacteriocin to food preservation.

  14. Potential of Lactic Streptococci to Produce Bacteriocin

    Science.gov (United States)

    Geis, Arnold; Singh, Jasjit; Teuber, Michael

    1983-01-01

    A survey was made on the bacteriocin-producing potential of lactic streptococci. Bacteriocin-like activities were isolated and partially purified from about 5% of the 280 strains investigated. The frequency of production varied from about 1% in Streptococcus lactis subsp. diacetylactis to 9 and 7.5% in S. lactis and Streptococcus cremoris, respectively. Eight strains of S. cremoris produced bacteriocins which, on the basis of heat stability at different pH values and inhibitory spectrum, could be divided into four types. From 54 S. lactis strains, 5 strains produced inhibitory substances, namely, three nisin-like antibiotics and two different bacteriocins. Only 1 of 93 S. lactis subsp. diacetylactis strains produced a bacteriocin which was very similar to bacteriocins of type I in S. cremoris. All of the bacteriocins that were partially purified by ammonium sulfate precipitation showed very limited inhibitory spectra. Most of the lactic streptococci and a few members of the genera Clostridium, Leuconostoc, and Pediococcus were inhibited. None of the bacteriocins acted on gram-negative bacteria. The bacteriocinogenic strains were also characterized on the basis of plasmid content. All strains possessed between one and nine plasmids ranging from 1 to 50 megadaltons. Images PMID:16346166

  15. Screening and characterization of novel bacteriocins from lactic acid bacteria.

    Science.gov (United States)

    Zendo, Takeshi

    2013-01-01

    Bacteriocins produced by lactic acid bacteria (LAB) are expected to be safe antimicrobial agents. While the best studied LAB bacteriocin, nisin A, is widely utilized as a food preservative, various novel ones are required to control undesirable bacteria more effectively. To discover novel bacteriocins at the early step of the screening process, we developed a rapid screening system that evaluates bacteriocins produced by newly isolated LAB based on their antibacterial spectra and molecular masses. By means of this system, various novel bacteriocins were identified, including a nisin variant, nisin Q, a two-peptide bacteriocin, lactococcin Q, a leaderless bacteriocin, lacticin Q, and a circular bacteriocin, lactocyclicin Q. Moreover, some LAB isolates were found to produce multiple bacteriocins. They were characterized as to their structures, mechanisms of action, and biosynthetic mechanisms. Novel LAB bacteriocins and their biosynthetic mechanisms are expected for applications such as food preservation and peptide engineering. PMID:23649268

  16. Compactifications of IIA supergravity on SU(2)-structure manifolds

    Energy Technology Data Exchange (ETDEWEB)

    Spanjaard, B.

    2008-07-15

    In this thesis, we study compactifications of type IIA supergravity on six-dimensional manifolds with an SU(2)-structure. A general study of six-dimensional manifolds with SU(2)-structure shows that IIA supergravity compactified on such a manifold should yield a four-dimensional gauged N=4 supergravity. We explicitly derive the bosonic spectrum, gauge transformations and action for IIA supergravity compactified on two different manifolds with SU(2)-structure, one of which also has an H{sup (3)}{sub 10}-flux, and confirm that the resulting four-dimensional theories are indeed N=4 gauged supergravities. In the second chapter, we study an explicit construction of a set of SU(2)-structure manifolds. This construction involves a Scherk-Schwarz duality twist reduction of the half-maximal six-dimensional supergravity obtained by compactifying IIA supergravity on a K3. This reduction results in a gauged N=4 four-dimensional supergravity, where the gaugings can be divided into three classes of parameters. We relate two of the classes to parameters we found before, and argue that the third class of parameters could be interpreted as a mirror flux. (orig.)

  17. Compactifications of IIA supergravity on SU(2)-structure manifolds

    International Nuclear Information System (INIS)

    In this thesis, we study compactifications of type IIA supergravity on six-dimensional manifolds with an SU(2)-structure. A general study of six-dimensional manifolds with SU(2)-structure shows that IIA supergravity compactified on such a manifold should yield a four-dimensional gauged N=4 supergravity. We explicitly derive the bosonic spectrum, gauge transformations and action for IIA supergravity compactified on two different manifolds with SU(2)-structure, one of which also has an H(3)10-flux, and confirm that the resulting four-dimensional theories are indeed N=4 gauged supergravities. In the second chapter, we study an explicit construction of a set of SU(2)-structure manifolds. This construction involves a Scherk-Schwarz duality twist reduction of the half-maximal six-dimensional supergravity obtained by compactifying IIA supergravity on a K3. This reduction results in a gauged N=4 four-dimensional supergravity, where the gaugings can be divided into three classes of parameters. We relate two of the classes to parameters we found before, and argue that the third class of parameters could be interpreted as a mirror flux. (orig.)

  18. Bacteriocins: Recent Trends and Potential Applications.

    Science.gov (United States)

    Bali, Vandana; Panesar, Parmjit S; Bera, Manab B; Kennedy, John F

    2016-04-01

    In the modern era, there is great need for food preservation in both developing and developed countries due to increasing demand for extending shelf life and prevention of spoilage of food material. With the emergence of new pathogens and ability of micro-organisms to undergo changes, exploration of new avenues for the food preservation has gained importance. Moreover, awareness among consumers regarding harmful effects of chemical preservatives has been increased. Globally, altogether there is increasing demand by consumers for chemical-free and minimal processed food products. Potential of bacteriocin and its application in reducing the microbiological spoilages and in the preservation of food is long been recognized. Bacteriocins are normally specific to closely related species without disrupting the growth of other microbial populations. A number of applications of bacteriocin have been reported for humans, live stock, aquaculture etc. This review is focused on recent trends and applications of bacteriocins in different areas in addition to their biopreservative potential. PMID:25117970

  19. Bacteriocin-producing Enterococci from Rabbit Meat

    OpenAIRE

    Szabóová, R.; Lauková, A.; Simonová, M.P,; Strompfová, V.; Chrastinová, L.

    2012-01-01

    Aims: Enterococci are lactic acid bacteria belonging to the division Firmicutes. They occur in different ecosystems, rabbits including. Enterococci can possess probiotic properties and produce antimicrobial substances-bacteriocins. Rabbit meat as nutritionally healthy food offers novel source to study bacteriocin-producing and/or probiotic enterococci. Methodology and results: Enterococci were detected from rabbit meat samples (42). Most of the isolates were allotted to the species Enterococ...

  20. Effect of Lactobacillus salivarius bacteriocin Abp118 on the mouse and pig intestinal microbiota.

    Directory of Open Access Journals (Sweden)

    Eliette Riboulet-Bisson

    Full Text Available Lactobacilli are gram-positive bacteria that are a subdominant element in the human gastrointestinal microbiota, and which are commonly used in the food industry. Some lactobacilli are considered probiotic, and have been associated with health benefits. However, there is very little culture-independent information on how consumed probiotic microorganisms might affect the entire intestinal microbiota. We therefore studied the impact of the administration of Lactobacillus salivarius UCC118, a microorganism well characterized for its probiotic properties, on the composition of the intestinal microbiota in two model animals. UCC118 has anti-infective activity due to production of the bacteriocin Abp118, a broad-spectrum class IIb bacteriocin, which we hypothesized could impact the microbiota. Mice and pigs were administered wild-type (WT L. salivarius UCC118 cells, or a mutant lacking bacteriocin production. The microbiota composition was determined by pyrosequencing of 16S rRNA gene amplicons from faeces. The data show that L. salivarius UCC118 administration had no significant effect on proportions of major phyla comprising the mouse microbiota, whether the strain was producing bacteriocin or not. However, L. salivarius UCC118 WT administration led to a significant decrease in Spirochaetes levels, the third major phylum in the untreated pig microbiota. In both pigs and mice, L. salivarius UCC118 administration had an effect on Firmicutes genus members. This effect was not observed when the mutant strain was administered, and was thus associated with bacteriocin production. Surprisingly, in both models, L. salivarius UCC118 administration and production of Abp118 had an effect on gram-negative microorganisms, even though Abp118 is normally not active in vitro against this group of microorganisms. Thus L. salivarius UCC118 administration has a significant but subtle impact on mouse and pig microbiota, by a mechanism that seems at least partially

  1. Bacteriocins From Lactic Acid Bacteria: Interest For Food Products Biopreservation

    OpenAIRE

    Dortu, C.; Thonart, Philippe

    2009-01-01

    Bacteriocins from lactic acid bacteria: interest for food products biopreservation. Bacteriocins from lactic acid bacteria are low molecular weight antimicrobial peptides. They have inhibitory activity against the bacteria that are closed related to the producer strains and a narrow inhibitory spectrum. Nevertheless, most of them have activity against some food-born pathogenic bacteria as Listeria monocytogenes. The application of bacteriocins or bacteriocin producing lactic acid bacteria in ...

  2. The Ecology of Bacteriocin-producing Strains of Streptococcus salivarius

    OpenAIRE

    Tompkins, G R; Tagg, J. R.

    2011-01-01

    Interest in bacteriocin-producing components of the human normal oral microbiota centres on their possible interference with colonisation by potentially pathogenic bacteria. Certain strains of Streptococcus salivarius produce bacteriocin-like agents displaying exceptional inhibitory activity toward Lancefield Group A streptococci. Four individuals were identified as naturally harbouring high proportions (> 90 per cent) of bacteriocin-producing strains of S. salivarius. Bacteriocinogenic is...

  3. Are bacteriocins underexploited? : Novel applications for old antimicrobials

    NARCIS (Netherlands)

    Montalbán-López, Manuel; Sánchez-Hidalgo, Marina; Valdivia, Eva; Martínez-Bueno, Manuel; Maqueda, Mercedes

    2011-01-01

    Bacteriocins are ribosomally synthesized (poly)peptides produced by almost all prokaryotic lineages. Bacteriocins from lactic acid bacteria (LAB) and bacteriocin-producer probiotic organisms have been thoroughly studied due to their wide spectra of action, the long-term use in food fermentations and

  4. Antibacterial efficacy of Nisin, Pediocin 34 and Enterocin FH99 against Listeria monocytogenes and cross resistance of its bacteriocin resistant variants to common food preservatives

    Directory of Open Access Journals (Sweden)

    G. Kaur

    2013-01-01

    Full Text Available Antilisterial efficiency of three bacteriocins, viz, Nisin, Pediocin 34 and Enterocin FH99 was tested individually and in combination against Listeria mononcytogenes ATCC 53135. A greater antibacterial effect was observed when the bacteriocins were combined in pairs, indicating that the use of more than one LAB bacteriocin in combination have a higher antibacterial action than when used individually. Variants of Listeria monocytogenes ATCC 53135 resistant to Nisin, Pediocin 34 and Enterocin FH99 were developed. Bacteriocin cross-resistance of wild type and their corresponding resistant variants were assessed and results showed that resistance to a bacteriocin may extend to other bacteriocins within the same class. Resistance to Pediocin 34 conferred cross resistance to Enterocin FH 99 but not to Nisin. Similarly resistance to Enterocin FH99 conferred cross resistance to Pediocin 34 but not to Nisin. Also, the sensitivity of Nisin, Pediocin 34 and Enterocin FH99 resistant variants of Listeria monocytogenes to low pH, salt, sodium nitrite, and potassium sorbate was assayed in broth and compared to the parental wild-type strain. The Nisin, Pediocin 34 and Enterocin FH99 resistant variants did not have intrinsic resistance to low pH, sodium chloride, potassium sorbate, or sodium nitrite. In no case were the bacteriocin resistant Listeria monocytogenes variants examined were more resistant to inhibitors than the parental strains.

  5. MYBPH inhibits NM IIA assembly via direct interaction with NMHC IIA and reduces cell motility

    Energy Technology Data Exchange (ETDEWEB)

    Hosono, Yasuyuki [Division of Molecular Carcinogenesis, Center for Neurological Diseases and Cancer, Nagoya University Graduate School of Medicine, Showa-ku, Nagoya 466-8550 (Japan); Usukura, Jiro [Division of Integrated Project, EcoTopia Science Institute, Nagoya University, Chikusa-ku, Nagoya 464-8603 (Japan); Yamaguchi, Tomoya; Yanagisawa, Kiyoshi; Suzuki, Motoshi [Division of Molecular Carcinogenesis, Center for Neurological Diseases and Cancer, Nagoya University Graduate School of Medicine, Showa-ku, Nagoya 466-8550 (Japan); Takahashi, Takashi, E-mail: tak@med.nagoya-u.ac.jp [Division of Molecular Carcinogenesis, Center for Neurological Diseases and Cancer, Nagoya University Graduate School of Medicine, Showa-ku, Nagoya 466-8550 (Japan)

    2012-11-09

    Highlights: Black-Right-Pointing-Pointer MYBPH inhibits NMHC IIA assembly and cell motility. Black-Right-Pointing-Pointer MYBPH interacts to assembly-competent NM IIA. Black-Right-Pointing-Pointer MYBPH inhibits RLC and NMHC IIA, independent components of NM IIA. -- Abstract: Actomyosin filament assembly is a critical step in tumor cell migration. We previously found that myosin binding protein H (MYBPH) is directly transactivated by the TTF-1 lineage-survival oncogene in lung adenocarcinomas and inhibits phosphorylation of the myosin regulatory light chain (RLC) of non-muscle myosin IIA (NM IIA) via direct interaction with Rho kinase 1 (ROCK1). Here, we report that MYBPH also directly interacts with an additional molecule, non-muscle myosin heavy chain IIA (NMHC IIA), which was found to occur between MYBPH and the rod portion of NMHC IIA. MYBPH inhibited NMHC IIA assembly and reduced cell motility. Conversely, siMYBPH-induced increased motility was partially, yet significantly, suppressed by blebbistatin, a non-muscle myosin II inhibitor, while more profound effects were attained by combined treatment with siROCK1 and blebbistatin. Electron microscopy observations showed well-ordered paracrystals of NMHC IIA reflecting an assembled state, which were significantly less frequently observed in the presence of MYBPH. Furthermore, an in vitro sedimentation assay showed that a greater amount of NMHC IIA was in an unassembled state in the presence of MYBPH. Interestingly, treatment with a ROCK inhibitor that impairs transition of NM IIA from an assembly-incompetent to assembly-competent state reduced the interaction between MYBPH and NMHC IIA, suggesting that MYBPH has higher affinity to assembly-competent NM IIA. These results suggest that MYBPH inhibits RLC and NMHC IIA, independent components of NM IIA, and negatively regulates actomyosin organization at 2 distinct steps, resulting in firm inhibition of NM IIA assembly.

  6. MYBPH inhibits NM IIA assembly via direct interaction with NMHC IIA and reduces cell motility

    International Nuclear Information System (INIS)

    Highlights: ► MYBPH inhibits NMHC IIA assembly and cell motility. ► MYBPH interacts to assembly-competent NM IIA. ► MYBPH inhibits RLC and NMHC IIA, independent components of NM IIA. -- Abstract: Actomyosin filament assembly is a critical step in tumor cell migration. We previously found that myosin binding protein H (MYBPH) is directly transactivated by the TTF-1 lineage-survival oncogene in lung adenocarcinomas and inhibits phosphorylation of the myosin regulatory light chain (RLC) of non-muscle myosin IIA (NM IIA) via direct interaction with Rho kinase 1 (ROCK1). Here, we report that MYBPH also directly interacts with an additional molecule, non-muscle myosin heavy chain IIA (NMHC IIA), which was found to occur between MYBPH and the rod portion of NMHC IIA. MYBPH inhibited NMHC IIA assembly and reduced cell motility. Conversely, siMYBPH-induced increased motility was partially, yet significantly, suppressed by blebbistatin, a non-muscle myosin II inhibitor, while more profound effects were attained by combined treatment with siROCK1 and blebbistatin. Electron microscopy observations showed well-ordered paracrystals of NMHC IIA reflecting an assembled state, which were significantly less frequently observed in the presence of MYBPH. Furthermore, an in vitro sedimentation assay showed that a greater amount of NMHC IIA was in an unassembled state in the presence of MYBPH. Interestingly, treatment with a ROCK inhibitor that impairs transition of NM IIA from an assembly-incompetent to assembly-competent state reduced the interaction between MYBPH and NMHC IIA, suggesting that MYBPH has higher affinity to assembly-competent NM IIA. These results suggest that MYBPH inhibits RLC and NMHC IIA, independent components of NM IIA, and negatively regulates actomyosin organization at 2 distinct steps, resulting in firm inhibition of NM IIA assembly.

  7. Adsorption of bacteriocins by ingestible silica compounds.

    Science.gov (United States)

    Wan, J; Gordon, J; Hickey, M W; Mawson, R F; Coventry, M J

    1996-08-01

    Bacteriocins including nisin, pediocin PO2, brevicin 286 and piscicolin 126 were adsorbed from culture supernates by various food-grade porous silica anti-caking agents and the food colourant, titanium dioxide. All the porous silica (calcium silicate or silicon dioxide) materials showed substantial capacity in adsorbing bacteriocin activities from the culture supernate and biological activity was recovered in the adsorbents. In contrast, the food colourant titanium dioxide adsorbed most of the bacteriocin activity from the supernate, with minimal biological activity retained in the adsorbent. Experiments with piscicolin 126 showed that optimum adsorption could be achieved with Micro-Cel E within 30 min, independent of the supernate pH (2.0-10.0). Piscicolin activity of up to 5 x 10(7) AU g(-1) of Micro-Cel E was obtained after adsorption from culture supernates and the adsorbed piscicolin demonstrated substantial biological activity against Listeria monocytogenes in both broth and a milk growth medium. PMID:8926221

  8. Applications of the bacteriocin, nisin.

    Science.gov (United States)

    Delves-Broughton, J; Blackburn, P; Evans, R J; Hugenholtz, J

    1996-02-01

    Nisin was first introduced commercially as a food preservative in the UK approximately 30 years ago. First established use was as a preservative in processed cheese products and since then numerous other applications in foods and beverages have been identified. It is currently recognised as a safe food preservative in approximately 50 countries. The established uses of nisin as a preservative in processed cheese, various pasteurised dairy products, and canned vegetables will be briefly reviewed. More recent applications of nisin include its use as a preservative in high moisture, hot baked flour products (crumpets) and pasteurised liquid egg. Renewed interest is evident in the use of nisin in natural cheese production. Considerable research has been carried out on the antilisterial properties of nisin in foods and a number of applications have been proposed. Uses of nisin to control spoilage lactic acid bacteria have been identified in beer, wine, alcohol production and low pH foods such as salad dressings. Further developments of nisin are likely to include synergistic action of nisin with chelators and other bacteriocins, and its use as an adjunct in novel food processing technology such as higher pressure sterilisation and electroporation. Production of highly purified nisin preparations and enhancement by chelators has led to interest in the use of nisin for human ulcer therapy, and mastitis control in cattle. PMID:8775979

  9. Studies of doublet plasmas in Doublet IIA

    International Nuclear Information System (INIS)

    Doublet plasma have been produced in Doublet IIA using an active field-shaping coil system. Significant increases in the electron density and energy confinement time have been observed for the doublet configuration relative to elliptic and circular plasmas in Doublet IIA

  10. Characterization of the amylovorin locus of Lactobacillus amylovorus DCE 471, producer of a bacteriocin active against Pseudomonas aeruginosa, in combination with colistin and pyocins.

    Science.gov (United States)

    Moreno, Maria R Foulquie; Baert, Barbara; Denayer, Sarah; Cornelis, Pierre; De Vuyst, Luc

    2008-09-01

    Lactobacillus amylovorus DCE 471 produces amylovorin L, a bacteriocin with an antibacterial activity against some strains of the Lactobacillus lineage. Based on the sequence of one active peptide, a gene encoding active amylovorin L was cloned and sequenced. Genome walking allowed us to sequence a larger fragment of 7577 bp of genomic DNA, with 12 predicted ORFs. The previously characterized amylovorin L peptide-encoding gene is preceded by another gene encoding a small polypeptide with a typical bacteriocin-processing double-glycine site, suggesting that amylovorin L is a two-component class IIb bacteriocin (amylovorin Lalpha/beta). Lalpha and Lbeta show the highest similarity to gassericin T from Lactobacillus gasseri SBT2055 and BlpN from Streptococcus pneumoniae R6, respectively, and to LafA and LafX, which form the lactacin F bacteriocin of Lactobacillus johnsonii NCC 533. As for other lactic acid bacteria bacteriocins, amylovorin L showed no activity against the Gram-negative opportunistic pathogen Pseudomonas aeruginosa on its own, but showed synergistic inhibitory activity when used in combination with the peptide antibiotic colistin, and, remarkably, with the P. aeruginosa soluble bacteriocins, pyocins S1 and S2. PMID:18803001

  11. Antimicrobial Activity of Bacteriocins and Their Applications

    Science.gov (United States)

    Drosinos, Eleftherios H.; Mataragas, Marios; Paramithiotis, Spiros

    Bacteriocins are peptides or proteins that exert an antimicrobial action against a range of microorganisms. Their production can be related to the antagonism within a certain ecological niche, as the producer strain, being itself immune to its action, generally gains a competitive advantage. Many Gram-positive and Gram-negative microorganisms have been found to produce bacteriocins. The former, and especially the ones produced by lactic acid bacteria, has been the field of intensive research during the last decades mainly due to their properties that account for their suitability in food preservation and the benefits arising from that, and secondarily due to the broader inhibitory spectrum compared to the ones produced by Gramnegative microorganisms.

  12. Antibacterial Activities of Bacteriocins: Application in Foods and Pharmaceuticals

    Directory of Open Access Journals (Sweden)

    Jia-YouFang

    2014-05-01

    Full Text Available Bacteriocins are a kind of ribosomal synthesized antimicrobial peptides produced by bacteria, which can kill or inhibit bacterial strains closely-related or non-related to produced bacteria, but will not harm the bacteria themselves by specific immunity proteins. Bacteriocins become one of the weapons against microorganisms due to the specific characteristics of large diversity of structure and function, natural resource, and being stable to heat. Many recent studies have purified and identified bacteriocins for application in food technology, which aims to extend food preservation time, treat pathogen disease and cancer therapy, and maintain human health. Therefore, bacteriocins may become a potential drug candidate for replacing antibiotics in order to treat multiple drugs resistance pathogens in the future. This review article summarizes different types of bacteriocins from bacteria. The latter half of this review focuses on the potential applications applications in food science and pharmaceutical industry.

  13. Bacteriocins: Novel Solutions to Age Old Spore-Related Problems?

    Science.gov (United States)

    Egan, Kevin; Field, Des; Rea, Mary C.; Ross, R. Paul; Hill, Colin; Cotter, Paul D.

    2016-01-01

    Bacteriocins are ribosomally synthesized antimicrobial peptides produced by bacteria, which have the ability to kill or inhibit other bacteria. Many bacteriocins are produced by food grade lactic acid bacteria (LAB). Indeed, the prototypic bacteriocin, nisin, is produced by Lactococcus lactis, and is licensed in over 50 countries. With consumers becoming more concerned about the levels of chemical preservatives present in food, bacteriocins offer an alternative, more natural approach, while ensuring both food safety and product shelf life. Bacteriocins also show additive/synergistic effects when used in combination with other treatments, such as heating, high pressure, organic compounds, and as part of food packaging. These features are particularly attractive from the perspective of controlling sporeforming bacteria. Bacterial spores are common contaminants of food products, and their outgrowth may cause food spoilage or food-borne illness. They are of particular concern to the food industry due to their thermal and chemical resistance in their dormant state. However, when spores germinate they lose the majority of their resistance traits, making them susceptible to a variety of food processing treatments. Bacteriocins represent one potential treatment as they may inhibit spores in the post-germination/outgrowth phase of the spore cycle. Spore eradication and control in food is critical, as they are able to spoil and in certain cases compromise the safety of food by producing dangerous toxins. Thus, understanding the mechanisms by which bacteriocins exert their sporostatic/sporicidal activity against bacterial spores will ultimately facilitate their optimal use in food. This review will focus on the use of bacteriocins alone, or in combination with other innovative processing methods to control spores in food, the current knowledge and gaps therein with regard to bacteriocin-spore interactions and discuss future research approaches to enable spores to be more

  14. Antibacterial Activity of Selected Standard Strains of Lactic Acid Bacteria Producing Bacteriocins – Pilot Study

    Directory of Open Access Journals (Sweden)

    Malgorzata Bodaszewska-Lubas

    2012-10-01

    Full Text Available  Introduction:In this paper, an attempt was made to evaluate the antibacterial potential of standard strains of lactic acid bacteria (LAB producing bacteriocins of various classes, thus demonstrating various mechanisms of cell membrane damages against the Streptococcus agalactiae strains (Group B Streptococcus, GBS, depending on surface polysaccharides and surface alpha-like protein genes.Materials/Methods:Antimicrobial property of the strains of L. plantarum C 11, L. sakei DSMZ 6333, and L. lactis ATCC 11454 producing bacteriocins: JK and EF plantaricins, sakacin and nisin, respectively, against the GBS strains was evaluated. The chosen to the study GBS strains were represented by serotypes Ia, Ib, II, III, V and they had bca, epsilon, rib, alp2 or alp3 alpha-like protein genes. The experiment was conducted by means of suspension culture and the bacteria count was determined using the serial dilution method.Results:A great ability of L. plantarum C 11 strain was proven to inhibit the GBS growth. The strain of L. sakei DSMZ 6333 did not demonstrate any ability to inhibit the growth of GBS, whereas L. lactis ATCC 11454 inhibited the growth of S. agalactiae indicator strains to a minor extent. Statistically significant differences were demonstrated between the GBS strains representing various serotypes against the antimicrobial activity of model LAB strains. The least sensitive to the activity of bacteriocins were the strains representing serotypes Ib and III, whereas the strains representing serotype II were the most sensitive. The sensitivity of the GBS strains to the antimicrobial activity of LAB was not dependent on alpha-like protein genes.Discussion:Among the LAB standard strains producing bacteriocins, the strongest antimicrobial property was observed in the strain of L. plantarum C 11. Because of the generally known and verified strong antagonistic property of the strains of L. plantarum species against indicator bacteria, it is necessary

  15. Something Old and Something New: An Update on the Amazing Repertoire of Bacteriocins Produced by Streptococcus salivarius.

    Science.gov (United States)

    Wescombe, Philip A; Heng, Nicholas C K; Burton, Jeremy P; Tagg, John R

    2010-03-01

    Streptococcus salivarius has an exclusive and intimate association with humans. We are its sole natural host, and its contribution to the relationship appears overwhelmingly benevolent. Beautifully adapted to its preferred habitat, the human tongue, it only rarely ventures far from this location in the healthy host and indeed appears ill-equipped to become invasive due to a scarcity of virulence attributes. We consider that its strategically advantageous lingual location and numerical predominance allow S. salivarius to carry out a population surveillance and modulation role within the oral microbiota. Some strains are armed with complex arrays of targeted antibiotic weaponry, much of which belongs to the lantibiotic class of bacteriocins and a key to their ability to assemble and utilize this armament is their possession of transmissible multi-bacteriocin-encoding megaplasmid DNA. This review traces the origins of research into S. salivarius bacteriocins and bacteriocin-like inhibitory substances, showcases some of the inhibitory activities that we currently have knowledge of, and speculates about potential directions for ongoing investigation and probiotic application of this previously under-rated human commensal. PMID:26780899

  16. MMBL proteins: from lectin to bacteriocin.

    Science.gov (United States)

    Ghequire, Maarten G K; Loris, Remy; De Mot, René

    2012-12-01

    Arguably, bacteriocins deployed in warfare among related bacteria are among the most diverse proteinacous compounds with respect to structure and mode of action. Identification of the first prokaryotic member of the so-called MMBLs (monocot mannose-binding lectins) or GNA (Galanthus nivalis agglutinin) lectin family and discovery of its genus-specific killer activity in the Gram-negative bacteria Pseudomonas and Xanthomonas has added yet another kind of toxin to this group of allelopathic molecules. This novel feature is reminiscent of the protective function, on the basis of antifungal, insecticidal, nematicidal or antiviral activity, assigned to or proposed for several of the eukaryotic MMBL proteins that are ubiquitously distributed among monocot plants, but also occur in some other plants, fish, sponges, amoebae and fungi. Direct bactericidal activity can also be effected by a C-type lectin, but this is a mammalian protein that limits mucosal colonization by Gram-positive bacteria. The presence of two divergent MMBL domains in the novel bacteriocins raises questions about task distribution between modules and the possible role of carbohydrate binding in the specificity of target strain recognition and killing. Notably, bacteriocin activity was also demonstrated for a hybrid MMBL protein with an accessory protease-like domain. This association with one or more additional modules, often with predicted peptide-hydrolysing or -binding activity, suggests that additional bacteriotoxic proteins may be found among the diverse chimaeric MMBL proteins encoded in prokaryotic genomes. A phylogenetic survey of the bacterial MMBL modules reveals a mosaic pattern of strongly diverged sequences, mainly occurring in soil-dwelling and rhizosphere bacteria, which may reflect a trans-kingdom acquisition of the ancestral genes. PMID:23176516

  17. CHARACTERIZATION OF BACTERIOCIN FROM PROBIOTIC LACTOBACILLUS PLANTARUM

    Directory of Open Access Journals (Sweden)

    A. Jayachitra*, C.M. Sukanya and N. Krithiga

    2012-11-01

    Full Text Available In our study, the sample (cheese was selected for isolation and identification of Lactobacillus species as local probiotic isolate. The strain was subjected to microscopic and macroscopic investigations for probiotic selection. The world health organization criteria (WHO were applied to all Lactobacillus species against E. coli, P. areoginosa, S. aerus, Chromobacterium, Serratia and A. flavus, antibiotic sensitivity test, acid and bile tolerance test, heamolytic activity. Antimicrobial compound called bacteriocin was partially purified. The Lactobacillus species was identified by 16S rRNA gene sequencing and specific catalase gene was also amplified. Data showed that Lactobacillus plantarum has a high inhibitory activity, tolerant to bile and acid, highly resistant to many antibiotics. Antimicrobial peptide was partially purified, characterized and bacteriocin produced by L. plantarum remained constant activity after heating at 121oC for 10 min. L. plantarum may be an alternative and promising way for eradicating many diseases. L. plantarum produces antimicrobial metabolites can give reasonable assurance of the control of pathogenic microorganisms. Increase the number of food-poisoning patients, the inhibition of the bacterial growth or production of enterotoxin such as verotoxins by administrating Lactobacilli bacteriocins would be of great importance. Lactobacillus fulfills the basic criteria required for probiotic strains which survive in in-vitro condition. The experimental strain exhibited strong antibacterial and antifungal activities against the pathogens. L. plantarum has high probiotic potential for eradicating many diseases, mainly the suppression of A. flavus which produce Aflatoxin. Pharmaceutical and nutritional industries are exploring more natural treatments for health conscious consumers as natural treatments have been effective.

  18. Potency Of Bacteriocin For Animal Health And Food Safety

    Directory of Open Access Journals (Sweden)

    Siti Chotiah

    2013-06-01

    Full Text Available The emergence of antibiotic resistance in many bacteria related to animal and public health stresses the importance of decreasing the use of antibiotics in animal production. The reduction of antibiotic application in livestock can only be achieved if alternative antimicrobial strategies are available. A number of strategies have been explored to control microbial pathogens and to improve growth and feed efficiency in livestock without the use of antibiotics. Bacteriocins have been more extensively studied and proposed as potential alternatives to conventional antibiotics in animal husbandry. Bacteriocins are antimicrobial peptides ribosomally synthesized by many species of Bacteria and some strains of Archaea. In general, bacteriocins just exhibited bactericidal or bacteriostatic activity against other bacteria that are closely related to the producing strain. The main mechanisms of bacteriocin activity vary from pore formation in cytoplasmic membranes to the inhibition of cell wall biosynthesis and enzyme activities (RNAse or DNAse in target cells. The use of bacteriocins in probiotic applications, as preservatives, and most excitingly as alternatives to conventional antibiotics is being broadly explored and studied. This review will describe the bacteriocins potency for animal health and food safety, as well as the results of bacteriocin study that had been conducted in Indonesia.

  19. Purification and certain properties of a bacteriocin from Streptococcus mutans.

    Science.gov (United States)

    Ikeda, T; Iwanami, T; Hirasawa, M; Watanabe, C; McGhee, J R; Shiota, T

    1982-03-01

    An inhibition factor from Streptococcus mutans strain C3603 (serotype c) was purified and isolated, and its properties indicated that it was a bacteriocin. Bacteriocin C3603 is a basic protein with a pI value of 10 and a molecular weight of 4,800. The activity of this bacteriocin was not affected by pH over a range of 1.0 to 12.0 or by storage at 100 degrees C for 10 min at pH 2.0 to 7.0 or storage at 121 degrees C for 15 min at pH 4.0. Pronase; papain, phospholipase C, trypsin, and alpha-amylase had no effect on the activity of the bacteriocin, whereas alpha-chymotrypsin and pancreatin were partially active against it. Bacteriocin activity was greater against certain S. mutans strains of serotypes b, c, e, and f than against certain S. mutans strains of serotypes a, d, and g. Bacteriocin C3603 was also effective against selected strains of S. sanguis, S. salivarius, S. bovis, S. faecium, S. lactis, Lactobacillus casei, L. plantarum, L. fermentum, Bifidobacterium bifidum, Bifidobacterium longum, Propionibacterium acnes, and Bacteroides melaninogenicus, but it was not effective against certain strains of Escherichia coli, Klebsiella pneumoniae, Corynebacterium parvum, and Candida albicans. The inhibition of S. mutans strains BHT and PS-14 by bacteriocin C3603 was found to be due to the bacteriocidal activity of the bacteriocin. When water or a diet containing bacteriocin C3603 was consumed by gnotobiotic and specific pathogen-free rats infected with S. mutans PS-14, the caries score was found to be significantly reduced. PMID:7068219

  20. Superpotentials in IIA compactifications with general fluxes

    International Nuclear Information System (INIS)

    We derive the effective N=1, D=4 supergravity for the seven main moduli of type IIA orientifolds with D6-branes, compactified on T6/(Z2xZ2) in the presence of general fluxes. We illustrate and apply a general method that relates the N=1 effective Kahler potential and superpotential to a consistent truncation of gauged N=4 supergravity. We identify the correspondence between various admissible fluxes, N=4 gaugings and N=1 superpotential terms. We construct explicit examples with different features: in particular, new IIA no-scale models and a model which admits a supersymmetric AdS4 vacuum with all seven main moduli stabilized

  1. Co-culture-inducible bacteriocin production in lactic acid bacteria.

    Science.gov (United States)

    Chanos, Panagiotis; Mygind, Tina

    2016-05-01

    It is common knowledge that microorganisms have capabilities, like the production of antimicrobial compounds, which do not normally appear in ideal laboratory conditions. Common antimicrobial discovery techniques require the isolation of monocultures and their individual screening against target microorganisms. One strategy to achieve expression of otherwise hidden antimicrobials is induction by co-cultures. In the area of bacteriocin-producing lactic acid bacteria, there has been some research focusing into the characteristics of co-culture-inducible bacteriocin production and particularly the molecular mechanism(s) of such interactions. No clear relationship has been seen between bacteriocin-inducing and bacteriocin-producing microorganisms. The three-component regulatory system seems to be playing a central role in the induction, but inducing compounds have not been identified or characterized. However, the presence of the universal messenger molecule autoinducer-2 has been associated in some cases with the co-culture-inducible bacteriocin phenotype and it may play the role in the additional regulation of the three-component regulatory system. Understanding the mechanisms of induction would facilitate the development of strategies for screening and development of co-culture bacteriocin-producing systems and novel products as well as the perseverance of such systems in food and down to the intestinal tract, possibly conferring a probiotic effect on the host. PMID:27037694

  2. Utilization of bacteriocin-producing bacteria in dairy products

    Directory of Open Access Journals (Sweden)

    Matěj Patrovský

    2016-07-01

    Full Text Available Lactic acid bacteria have been used since ancient times for food preparation and for bio-conservation by fermentation. Selected strains are capable of producing antimicrobial peptides - bacteriocins, which can be natural preservatives, especially in products with short shelf lives. The present study is focused on inhibitory effects of the bacteriocin-producing bacteria strains Enterococcus faecium, Pediococccus acidilactici and Lactobacillus plantarum against Listeria innocua as an indicator microorganism. Freeze-dried preparations of bacterial strains producing particular bacteriocins were tested by agar well-diffusion assay and by the traditional spread plate method. Plantaricin exhibited the highest anti-listerial effect among the tested bacteriocins. Pediocin also demonstrated a distinct inhibitory effect, but enterocin appeared to be heat labile and its efficiency was also suppressed under cold storage conditions. Plantaricin reduced Listeria innocua counts by 1 log in dairy spread made from cheese and quark. The formation of bacteriocins by various Lactobacillus plantarum strains were substantially influenced by the cultivation conditions of the mother culture and by the microbial preparation process before freeze-drying. Bacteriocins introduced into foodstuffs via protective cultures in situ offer new perspectives on enhancing food quality and safety.

  3. Superpotentials in IIA compactifications with general fluxes

    Energy Technology Data Exchange (ETDEWEB)

    Derendinger, J.-P. [Physics Institute, Neuchatel University, Breguet 1, CH-2000 Neuchatel (Switzerland); Kounnas, C. [Laboratoire de Physique Theorique, Ecole Normale Superieure, 24 rue Lhomond, F-75231 Paris cedex 05 (France); CERN, Physics Department, Theory Division, CH-1211 Geneva 23 (Switzerland); Petropoulos, P.M. [Centre de Physique Theorique, Ecole Polytechnique, F-91128 Palaiseau (France); Zwirner, F. [CERN, Physics Department, Theory Division, CH-1211 Geneva 23 (Switzerland) and Dipartimento di Fisica, Universita di Roma ' La Sapienza' and INFN, Sezione di Roma, P.le A. Moro 2, I-00185 Rome (Italy)]. E-mail: fabio.zwirner@roma1.infn.it

    2005-05-23

    We derive the effective N=1, D=4 supergravity for the seven main moduli of type IIA orientifolds with D6-branes, compactified on T{sup 6}/(Z{sub 2}xZ{sub 2}) in the presence of general fluxes. We illustrate and apply a general method that relates the N=1 effective Kahler potential and superpotential to a consistent truncation of gauged N=4 supergravity. We identify the correspondence between various admissible fluxes, N=4 gaugings and N=1 superpotential terms. We construct explicit examples with different features: in particular, new IIA no-scale models and a model which admits a supersymmetric AdS{sub 4} vacuum with all seven main moduli stabilized.

  4. Characterization and Stability of Tanshinone IIA Solid Dispersions with Hydroxyapatite

    Directory of Open Access Journals (Sweden)

    Weiguang Li

    2013-03-01

    Full Text Available Solid dispersions of tanshinone IIA (TanIIA using hydroxyapatite (HAp as the dispersing carrier (TanIIA-HAp SDs were prepared by the solvent evaporation method. The formed solid dispersions were characterized by scanning electron microscopy (SEM, differential scanning calorimetry analysis (DSC, X-ray powder diffraction (XRPD and Fourier transforms infrared (FTIR spectroscopy. The in vitro dissolution rate and the stability of TanIIA-HAp SDs were also evaluated. DSC and XRPD showed that TanIIA was changed from a crystalline to an amorphous form. FTIR suggested the presence of interactions between TanIIA and HAp in solid dispersions. The result of an in vitro dissolution study showed that the dissolution rate of TanIIA-HAp SDs was nearly 7.11-folds faster than free TanIIA. Data from stability studies for over one year of TanIIA-HAp SDs performed under room temperature revealed no significant differences in drug content and dissolution behavior. All these results indicated that HAp may be a promising carrier for improving the oral absorption of TanIIA.

  5. Agujeros negros cu\\'anticos en la teor\\'ia de cuerdas tipo-IIA

    OpenAIRE

    Bueno, Pablo

    2013-01-01

    In the context of Type-IIA String Theory compactified to four dimensions on a Calabi-Yau manifold (CY), we study the effect of considering perturbative and non-perturbative corrections (in alpha prime) to the prepotential of the resulting effective Supergravity theory on the space of black hole solutions. Considering the large volume limit of the CY, in which the non-perturbative corrections are exponentially suppressed, we define a new class of solutions which turn out to be genuinely quantu...

  6. Bacteriocins produced by lactic acid bacteria: A review

    Directory of Open Access Journals (Sweden)

    Vesković-Moračanin Slavica M.

    2014-01-01

    Full Text Available Lactic acid bacteria (LAB have an essential role in the production of fermented products. With their metabolic activity, they influence the ripening processes - leading to desired sensory qualities while at the same time inhibiting the growth of undesired microorganisms. Because of their dominant role during fermentation and because of a long tradition of utilization, Lhave been designated as “safe microbiota”. Biological protection of LAB, as a naturally present and/or selected and intentionally added microflora, is realized through the production of non-specific (lactic acid, acetic acid and other volatile organic acids, hydrogen peroxide, diacetyl, etc and specific metabolites, bacteriocins. Bacteriocins are extracellularly released proteins or peptides which possess certain antibacterial activity towards certain types of microorganisms, usually related to the producing bacteria. Today, bacteriocins represent a very interesting potential for their application in the food industry. Their application can reduce the use of synthetic preservatives and/or the intensity of thermal treatment during food production consumer’s need for safe, fresh and minimally-processed food. With the intention of realizing this potential to the fullest, it is necessary to understand the nature of bacteriocins, their production mechanisms, regulations and actions, as well as the influence of external factors on the their antimicrobial activity. The composition of food, i.e. its characteristics (pH, temperature, ingredients and additives, types and quantities of epiphytic microbiota and the actual technological process used in production, can all influence the stability and activity of the added bacteriocins. The future research in this field should also aim to clarify this unknown aspect of the application of bacteriocins, to provide the necessary knowledge about the optimization of the external conditions and open up the possibility of discovering their new

  7. Production of bacteriocin by Virgibacillus salexigens isolated from "terasi": a traditionally fermented shrimp paste in Indonesia.

    Science.gov (United States)

    Kobayashi, Takeshi; Agustini, Tri Winarni; Ibrahim, Ratna; Kamei, Kaeko; Kondo, Akihiro; Kajiwara, Michika; Ooka, Yoshihiro; Nakamura, Hidetoshi; Terahara, Takeshi; Imada, Chiaki

    2016-03-01

    A natural antibacterial-substance-producing gram-positive bacterium was isolated from terasi shrimp paste, a popular fermented product in Indonesia. This strain, a spore-forming and strictly aerobic bacterium, was identified as Virgibacillus salexigens by 16S rRNA gene sequence analysis. The antibacterial substance purified from the precipitated product in the culture supernatant of the strain using ammonium sulfate showed a broad inhibition spectrum against gram-positive bacteria, including a typical foodborne bacterium, namely, Listeria monocytogenes. The antibacterial activity of the substance was inactivated by treatments with various proteolytic enzymes. It was stable after heating or pH treatment, and approximately 60% of the initial activity remained even after heating at 121 °C for 15 min. In addition, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis indicated that its monoisotopic mass weight was 5318.4 Da (M+H)(+). On the basis of the results obtained by the automated Edman degradation technique and MALDI-TOF MS analysis, the substance can be classified as a member of Class IId bacteriocins, but it could not be identified as any of the previously purified substances except for the putative bacteriocin predicted from the draft genome sequence data of gram-positive bacteria such as Virgibacillus and Bacillus strains. PMID:26873558

  8. Bacteriocins from the rhizosphere microbiome – from an agriculture perspective

    Directory of Open Access Journals (Sweden)

    Sowmyalakshmi eSubramanian

    2015-10-01

    Full Text Available Bacteria produce and excrete a versatile and dynamic suit of compounds to defend against microbial competitors and mediate local population dynamics. These include a wide range of broad-spectrum non-ribosomally synthesized antibiotics, lytic enzymes, metabolic by-products, proteinaceous exotoxins and ribosomally produced antimicrobial peptides (bacteriocins. Most bacteria produce at least one bacteriocin. Bacteriocins are of interest in the food industry as natural preservatives and in the probiotics industry, leading to extensive studies on lactic acid bacteria (colicin produced by Escherichia coli is a model bacteriocin. Recent studies have projected use of bacteriocins in veterinary medicine and in agriculture, as a biostimulants of plant growth and development and as biocontrol agents. For example, bacteriocins such as Cerein 8A, Bac-GM17, putidacin, Bac 14B, amylocyclicin have been studied for their mechanisms of anti-microbial activity. Bac IH7 promotes tomato and musk melon plant growth. Thuricin 17 (Th17 is the only bacteriocin studied extensively for plant growth promotion and at the molecular level. Th17 functions as a bacterial signal compound, promoting plant growth in legumes and non-legumes. In Arabidopsis thaliana and Glycine max Th17 increased phytohormones IAA and SA at 24 h post treatment. At the proteome level Th17 treatment of 3-week-old A. thaliana rosettes led to > 2-fold changes in activation of the carbon and energy metabolism pathway proteins, 24 h post treatment. At 250 mM NaCl stress, the control plants under osmotic-shock shut down most of carbon-metabolism and activated energy-metabolism and antioxidant pathways. Th17 treated plants, at 250 mM NaCl, retained meaningful levels of the light harvesting complex, photosystem I and II proteins and energy and antioxidant pathways were activated, so that rosettes could better withstand the salt stress. In Glycine max, Th17 helped seeds germinate in the presence of Na

  9. Bacteriocins from the rhizosphere microbiome - from an agriculture perspective.

    Science.gov (United States)

    Subramanian, Sowmyalakshmi; Smith, Donald L

    2015-01-01

    Bacteria produce and excrete a versatile and dynamic suit of compounds to defend against microbial competitors and mediate local population dynamics. These include a wide range of broad-spectrum non-ribosomally synthesized antibiotics, lytic enzymes, metabolic by-products, proteinaceous exotoxins, and ribosomally produced antimicrobial peptides (bacteriocins). Most bacteria produce at least one bacteriocin. Bacteriocins are of interest in the food industry as natural preservatives and in the probiotics industry, leading to extensive studies on lactic acid bacteria (colicin produced by Escherichia coli is a model bacteriocin). Recent studies have projected use of bacteriocins in veterinary medicine and in agriculture, as biostimulants of plant growth and development and as biocontrol agents. For example, bacteriocins such as Cerein 8A, Bac-GM17, putidacin, Bac 14B, amylocyclicin have been studied for their mechanisms of anti-microbial activity. Bac IH7 promotes tomato and musk melon plant growth. Thuricin 17 (Th17) is the only bacteriocin studied extensively for plant growth promotion, including at the molecular level. Th17 functions as a bacterial signal compound, promoting plant growth in legumes and non-legumes. In Arabidopsis thaliana and Glycine max Th17 increased phytohormones IAA and SA at 24 h post treatment. At the proteome level Th17 treatment of 3-week-old A. thaliana rosettes led to >2-fold changes in activation of the carbon and energy metabolism pathway proteins, 24 h post treatment. At 250 mM NaCl stress, the control plants under osmotic-shock shut down most of carbon-metabolism and activated energy-metabolism and antioxidant pathways. Th17 treated plants, at 250 mM NaCl, retained meaningful levels of the light harvesting complex, photosystems I and II proteins and energy and antioxidant pathways were activated, so that rosettes could better withstand the salt stress. In Glycine max, Th17 helped seeds germinate in the presence of NaCl stress, and was

  10. Cloning, sequencing, and expression in Escherichia coli of lcnB, a third bacteriocin determinant from the lactococcal bacteriocin plasmid p9B4-6.

    OpenAIRE

    van Belkum, Marco J.; Kok, Jan; Venema, Gerhardus

    1992-01-01

    On the bacteriocin plasmid p9B4-6 of Lactococcus lactis subsp. cremoris 9B4, a third bacteriocin determinant was identified. The genes encoding bacteriocin production and immunity resided on a 1.2-kb CelII-ScaI fragment and were located adjacent to one of two previously identified bacteriocin operons (M. J. van Belkum, B. J. Hayema, R. E. Jeeninga, J. Kok, and G. Venema, Appl. Environ. Microbiol. 57:492-498, 1991). The fragment was sequenced and analyzed by deletion and mutation analyses. The...

  11. Effects of starch synthase IIa gene dosage on grain, protein and starch in endosperm of wheat.

    Science.gov (United States)

    Konik-Rose, Christine; Thistleton, Jenny; Chanvrier, Helene; Tan, Ihwa; Halley, Peter; Gidley, Michael; Kosar-Hashemi, Behjat; Wang, Hong; Larroque, Oscar; Ikea, Joseph; McMaugh, Steve; Regina, Ahmed; Rahman, Sadequr; Morell, Matthew; Li, Zhongyi

    2007-11-01

    Starch synthases (SS) are responsible for elongating the alpha-1,4 glucan chains of starch. A doubled haploid population was generated by crossing a line of wheat, which lacks functional ssIIa genes on each genome (abd), and an Australian wheat cultivar, Sunco, with wild type ssIIa alleles on each genome (ABD). Evidence has been presented previously indicating that the SGP-1 (starch granule protein-1) proteins present in the starch granule in wheat are products of the ssIIa genes. Analysis of 100 progeny lines demonstrated co-segregation of the ssIIa alleles from the three genomes with the SGP-1 proteins, providing further evidence that the SGP-1 proteins are the products of the ssIIa genes. From the progeny lines, 40 doubled haploid lines representing the eight possible genotypes for SSIIa (ABD, aBD, AbD, ABd, abD, aBd, Abd, abd) were characterized for their grain weight, protein content, total starch content and starch properties. For some properties (chain length distribution, pasting properties, swelling power, and gelatinization properties), a progressive change was observed across the four classes of genotypes (wild type, single nulls, double nulls and triple nulls). However, for other grain properties (seed weight and protein content) and starch properties (total starch content, granule morphology and crystallinity, granule size distribution, amylose content, amylose-lipid dissociation properties), a statistically significant change only occurred for the triple nulls, indicating that all three genes had to be missing or inactive for a change to occur. These results illustrate the importance of SSIIa in controlling grain and starch properties and the importance of amylopectin fine structure in controlling starch granule properties in wheat. PMID:17721773

  12. The exceptional story of massive IIA supergravity

    CERN Document Server

    Ciceri, Franz; Inverso, Gianluca

    2016-01-01

    The framework of exceptional field theory is extended by introducing consistent deformations of its generalised Lie derivative. For the first time, massive type IIA supergravity is reproduced geometrically as a solution of the section condition. This provides a unified description of all ten- and eleven-dimensional maximal supergravities. The action of the E7 deformed theory is constructed, and reduces to those of exceptional field theory and gauged maximal supergravity in respective limits. The relation of this new framework to other approaches for generating the Romans mass non-geometrically is discussed.

  13. High altitude balloon experiments at IIA

    Science.gov (United States)

    Nayak, Akshata; Sreejith, A. G.; Safonova, Margarita; Murthy, Jayant

    Recent advances in balloon experiments as well as in electronics have made it possible to fly scientific payloads at costs accessible to university departments. We have begun a program of high altitude ballooning at the Indian Institute of Astrophysics, Bengaluru. The primary purpose of this activity is to test low-cost ultraviolet (UV) payloads for eventual space flight, but we will also try scientific exploration of the phenomena occurring in the upper atmosphere, including sprites and meteorite impacts. We present the results of the initial experiments carried out at the CREST campus of IIA, Hosakote, and describe our plans for the future.

  14. Bacteriocin-mediated competition in cystic fibrosis lung infections

    DEFF Research Database (Denmark)

    Ghoul, Melanie; West, Stuart A.; Johansen, Helle Krogh;

    2015-01-01

    , especially human pathogens, remains to be tested. We examined the role of bacteriocins in competition using Pseudomonas aeruginosa strains infecting lungs of humans with cystic fibrosis (CF). We assessed the ability of different strains to kill each other using phenotypic assays, and sequenced their genomes...

  15. Antimycobacterial activity of bacteriocins and their complexes with liposomes

    Science.gov (United States)

    Bacteriocins (Bcn) are natural peptides that are secreted by taxonomically distinct bacteria which exert bactericidal activity against other bacterial species. Their capacity to inhibit growth of virulent Mycobacterium tuberculosis H37Rv was evaluated in this study. Five Bcn were purified from sel...

  16. Fungicidal effect of bacteriocins harvested from Bacillus spp.

    Directory of Open Access Journals (Sweden)

    Adetunji, V. O.

    2013-01-01

    Full Text Available Aims: This study investigated the ability of bacteriocins isolated from Bacillus spp. (Bacillus species to inhibit fourdifferent yeast isolates obtained from common food products (nono, yoghurt, ogi and cheese commonly consumed byNigerians with minimal heat treatment.Methodology and results: Forty-five Bacillus spp. was isolated and identified from common food products usingcultural, morphological, physiological and biochemical characteristics. These isolates were tested for antimicrobialactivity against Salmonella enteritidis (3, Micrococcus luteus (1 and Staphylococcus aureus (2. Eight bacteriocinproducing strains were identified from an over- night broth culture centrifugated at 3500 revolutions for five minutes.Fungicidal effects of these bacteriocins were tested against four yeast strains using the Agar Well Diffusion method. Thebacteriocins produced wide zones of inhibition ranging from 5.9±0.000 to 24.00±0.000 mm against the 4 yeast strainstested. There was a significant difference (at p<0.05 between the yeast organisms and the bacteriocins from theBacillus spp.Conclusion, significance and impact of study: The study reveals the antifungal property of bacteriocins from Bacillusspp. and serves therefore as a base for further studies in its use in the control of diseases and extension of shelf-life ofproducts prone to fungi contamination.

  17. Different bacteriocin activities of Streptococcus mutans reflect distinct phylogenetic lineages

    DEFF Research Database (Denmark)

    Balakrishnan, M; Simmonds, RS; Kilian, Mogens;

    2002-01-01

    Bacteriocins produced by mutans streptococci are known as mutacins. In this study 16 broadly active mutacin-producing Streptococcus mutans strains from New Zealand, North America and Europe were classified into four groups (A-D) on the basis of differences in their activity in deferred antagonism...

  18. Secretory Phospholipase A2-IIA and Cardiovascular Disease

    DEFF Research Database (Denmark)

    Holmes, Michael V; Simon, Tabassome; Exeter, Holly J;

    2013-01-01

    This study sought to investigate the role of secretory phospholipase A2 (sPLA2)-IIA in cardiovascular disease.......This study sought to investigate the role of secretory phospholipase A2 (sPLA2)-IIA in cardiovascular disease....

  19. POTENTIAL IN VITRO ANTI-HELICOBACTER ACTIVITY OF BACTERIOCIN AND BACTERIOCIN-LIKE COMPOUNDS PRODUCED BY LACTOBACILLI

    Directory of Open Access Journals (Sweden)

    Mohammed A. Ramadan

    2014-10-01

    Full Text Available The study was designed for screening of the potential activity of lactic acid bacteria against Helicobacter pylori and other enteropathogenic organisms. A total of 40 samples including natural cow milk and fresh infant stools were tested for the presence of lactic acid bacteria. Of these samples, 73 lactic acid bacterial isolates were recovered on MRS agar medium using the streak-plate method. Isolates inducing probiotic effect were tested under microaerophilic conditions against standard cultures of H. pylori, Esherichia coli and Salmonella enteritidis. The data obtained showed that five isolates of lactic acid bacteria were able to produce bacteriocin or bacteriocin-like compounds. Sequencing of 16S rRNA gene revealed that five isolates belonged to Lactobacillus rhamnosus and Lactobacillus plantarum in addition to other lactic acid bacteria. The most effective isolate (LAB1 showed a marked large inhibition zone against H. pylori. The bacteriocin or bacteriocin like compound(s produced by lactobacilli were further analyzed and characterized. We can conclude that probiotics might be useful in the prophylaxis or as co-therapy for treatment of H. pylori infections.

  20. Position of nonmuscle myosin heavy chain IIA (NMMHC-IIA) mutations predicts the natural history of MYH9-related disease

    DEFF Research Database (Denmark)

    Pecci, A.; Panza, E.; Pujol-Moix, N.;

    2008-01-01

    MYH9-related disease (MYH9-RD) is a rare autosomal-dominant disorder caused by mutations in MYH9, the gene for the heavy chain of nonmuscle myosin IIA (NMMHC-IIA). All patients present from birth with macrothrombocytopenia, but in infancy or adult life, some of them develop sensorineural deafness...

  1. Purification and Characterization of a Bacteriocin Produced by Lactobacillus lactis Isolated from Marine Environment

    Directory of Open Access Journals (Sweden)

    P. Manivasagan

    2010-03-01

    Full Text Available Bacteriocin producing Lactobacillus lactis strain isolated from marine environment, showed broadrange of antibacterial activity against some major food borne pathogens. Maximum bacteriocin production wasobserved at 30°C , pH 6.0 and 1.5% sodium chloride solution. In addition of enzymes, "-amylase, DNase,RNase and lipase were slightly positive effect bacteriocin production. Proteinase K and pepsin were stronglyinhibited bacteriocin production. Among detergents, Sodium dodecyl sulphate (SDS, Tween 80 and TritoneX-100 stimulated bacteriocin production and strongly inhibited by EDTA and urea. The bacteriocin has purifiedby ammonium sulphate precipitate and ion exchange (DEAE cellulose chromatography. Biochemically it waspure protein moiety and the molecular weight was 94 kDa. The study revealed the possibility of usingbacteriocin as a food preservative and the L. lactis strain as probiotic.

  2. Conjugal transfer and characterization of bacteriocin plasmids in group N (lactic acid) streptococci.

    OpenAIRE

    Neve, H.; Geis, A.; Teuber, M

    1984-01-01

    Thirteen bacteriocin-producing strains of group N (lactic acid) streptococci were screened for their potential to transfer this property by conjugation to Streptococcus lactis subsp. diacetylactis Bu2-60. Bacteriocin production in three strains was plasmid encoded as shown by conjugal transfer and by analysis of cured, bacteriocin-negative derivatives of the donor strains and the transconjugants. With Streptococcus cremoris strains 9B4 and 4G6 and S. lactis subsp. diacetylactis 6F7 as donors,...

  3. History, Current Knowledge, and Future Directions on Bacteriocin Research in Lactic Acid Bacteria

    Science.gov (United States)

    Nes, Ingolf F.

    All organisms, both eukaryotic organisms and bacteria, are able to produce ribosomally antimicrobial peptides. In bacteria, such compounds are referred to as bacteriocins. The history of bacteriocins goes back to the early 1920s. One has experienced many disappointments in the efforts how to put these compounds into practical use despite being one of the most promising groups of antimicrobial agents to fight bacterial pathogens. However, today, we see new possibilities how to take advantage of such peptides for the benefit of man and animals. Bacteriocin production has become an important property of probiotic bacteria, and targeted use of bacteriocins to fight certain pathogens may have a future.

  4. Bacteriocins from lactic acid bacteria and their applications in meat and meat products.

    Science.gov (United States)

    Woraprayote, Weerapong; Malila, Yuwares; Sorapukdee, Supaluk; Swetwiwathana, Adisorn; Benjakul, Soottawat; Visessanguan, Wonnop

    2016-10-01

    Meat and meat products have always been an important part of human diet, and contain valuable nutrients for growth and health. Nevertheless, they are perishable and susceptible to microbial contamination, leading to an increased health risk for consumers as well as to the economic loss in meat industry. The utilization of bacteriocins produced by lactic acid bacteria (LAB) as a natural preservative has received a considerable attention. Inoculation of bacteriocin-producing LAB cell as starter or protective cultures is suitable for fermented meats, whilst the direct addition of bacteriocin as food additive is more preferable when live cells of LAB could not produce bacteriocin in the real meat system. The incorporation of bacteriocins in packaging is another way to improve meat safety to avoid direct addition of bacteriocin to meat. Utilization of bacteriocins can effectively contribute to food safety, especially when integrated into hurdle concepts. In this review, LAB bacteriocins and their applications in meat and meat products are revisited. The molecular structure and characteristics of bacteriocins recently discovered, as well as exemplary properties are also discussed. PMID:27118166

  5. Bacteriocins: molecules of fundamental impact on the microbial ecology and potential food biopreservatives

    Directory of Open Access Journals (Sweden)

    Evandro Leite de Souza

    2005-07-01

    Full Text Available Bacteriocins are proteic molecules synthesized for various lineages of Gram-positive and Gram-negative bacteria when exposed to stressful conditions. Bacteriocins have been characterized as molecules of high antimicrobial property even at low concentrations, provoking the microbial survival inhibition by antibiosis. These substances have their synthesis mediated for genetic mechanisms and develop their lethal action on the microbial cell by multiples mechanisms that can act of isolated or concomitant way culminating with microbial cell killing. This molecules class presents characteristic of stability to heat, low pH, refrigeration and freezing, and resistance to weak organics solvents, salts and enzymes. On the other hand, they are very sensitive to proteolytic enzymes action. Bacteriocins could appear as potential agents to be applied in food conservation systems in order to provide microbiologically stable foods.Bacteriocinas são moléculas protéicas sintetizadas por várias linhagens de bactérias Gram-positivas e Gram-negativas quando submetidas a condições de stress. São ainda caracterizadas como moléculas de alto poder antimicrobiano mesmo em baixas concentrações, provocando a inibição da sobrevivência microbiana através de uma ação de antibiose. As bacteriocinas têm seu processo de síntese mediado por mecanismos genéticos, e desenvolvem sua ação letal sobre a célula microbiana por intermédio de múltiplos mecanismos que podem agir de forma isolada ou concomitante culminando com a morte da célula microbiana. Estas moléculas apresentam características de estabilidade ao calor, baixo pH, refrigeração, congelamento, resistência a ácidos orgânicos fracos, sais e enzimas, porém são muito sensíveis à enzimas proteolíticas. Assim, as bacteriocinas podem aparecer como potenciais agentes para serem aplicados em sistemas de conservação de alimentos com objetivo de prover alimentos microbiologicamente estáveis.

  6. The dual role of bacteriocins as anti- and probiotics

    OpenAIRE

    Gillor, O.; Etzion, A.; Riley, M. A.

    2008-01-01

    Bacteria employed in probiotic applications help to maintain or restore a host's natural microbial floral. The ability of probiotic bacteria to successfully outcompete undesired species is often due to, or enhanced by, the production of potent antimicrobial toxins. The most commonly encountered of these are bacteriocins, a large and functionally diverse family of antimicrobials found in all major lineages of Bacteria. Recent studies reveal that these proteinaceous toxins play a critical role ...

  7. Recent patents on bacteriocins: food and biomedical applications.

    Science.gov (United States)

    Benmechernene, Zineb; Fernandez-No, Inmaculada; Kihal, Mebrouk; Böhme, Karola; Calo-Mata, Pilar; Barros-Velazquez, Jorge

    2013-04-01

    Most types of bacteria produce bacteriocins, which are proteinaceous extracellular compounds that can inhibit the growth of other undesirable microorganisms. Bacteriocins are receiving increasing attention, due to their many applications, ranging from their initial application in strategies for food preservation to more recent proposed uses in biomedical strategies aimed at fighting certain bacterial infections. Thus, while nisin has a long history of use as a safe additive in certain food products for the purpose of food preservation, certain bacteriocin-producing lactic acid bacteria, which are generally recognised as safe microorganisms, or their extracellular extracts are receiving increased attention as protective cultures or antimicrobial extracts in minimally processed food products. More recently, a number of these bacteriocinproducing cultures have been proposed for use in other applications, such as in probiotics, for the inhibition of biofilms in the food industry, or even as coadjuvants of combined therapeutical strategies along with other antimicrobial agents in biomedical applications. This review aims to provide a brief overview of the most relevant recent patents in this field. PMID:22921084

  8. Genetic Organization and Mode of Action of a Novel Bacteriocin, Bacteriocin 51: Determinant of VanA-Type Vancomycin-Resistant Enterococcus faecium▿†

    OpenAIRE

    Yamashita, Hitoshi; Tomita, Haruyoshi; Inoue, Takako; Ike, Yasuyoshi

    2011-01-01

    Bacteriocin 51 (Bac 51) is encoded on the mobile plasmid pHY (6,037 bp), which was isolated from vancomycin-resistant Enterococcus faecium VRE38. Bacteriocin 51 is active against E. faecium, E. hirae, and E. durans. Sequence analysis of pHY showed that it encodes nine open reading frames (ORFs) from ORF1 to ORF9 (in that order). Genetic analysis suggested that ORF1 and ORF2, which were designated bacA and bacB, respectively, are the bacteriocin and immunity genes. bacA encodes a 144-amino-aci...

  9. Japanese contributions to IAEA INTOR workshop, phase IIA

    International Nuclear Information System (INIS)

    Tritium breeding blanket is incorporated in the INTOR design based on economic and tritium availability considerations. In Phase IIA, critical issues on 'Tritium', which were identified during the Phase I Workshop, were investigated. Main objectives of Phase IIA are to develop a tritium breeding blanket and to evaluate tritium containment. Data base assessments of tritium containment were made. The design of the tritium breeding blanket was also revised. (author)

  10. Inhibitory effect of tanshinone IIA on rat hepatic stellate cells.

    Directory of Open Access Journals (Sweden)

    Ya-Wei Liu

    Full Text Available Anti-inflammation via inhibition of NF-κB pathways in hepatic stellate cells (HSCs is one therapeutic approach to hepatic fibrosis. Tanshinone IIA (C19H18O3, Tan IIA is a lipophilic diterpene isolated from Salvia miltiorrhiza Bunge, with reported anti-inflammatory activity. We tested whether Tan IIA could inhibit HSC activation.The cell line of rat hepatic stellate cells (HSC-T6 was stimulated with lipopolysaccharide (LPS (100 ng/ml. Cytotoxicity was assessed by MTT assay. HSC-T6 cells were pretreated with Tan IIA (1, 3 and 10 µM, then induced by LPS (100 ng/ml. NF-κB activity was evaluated by the luciferase reporter gene assay. Western blotting analysis was performed to measure NF-κB-p65, and phosphorylations of MAPKs (ERK, JNK, p38. Cell chemotaxis was assessed by both wound-healing assay and trans-well invasion assay. Quantitative real-time PCR was used to detect gene expression in HSC-T6 cells.All concentrations of drugs showed no cytotoxicity against HSC-T6 cells. LPS stimulated NF-κB luciferase activities, nuclear translocation of NF-κB-p65, and phosphorylations of ERK, JNK and p38, all of which were suppressed by Tan IIA. In addition, Tan IIA significantly inhibited LPS-induced HSCs chemotaxis, in both wound-healing and trans-well invasion assays. Moreover, Tan IIA attenuated LPS-induced mRNA expressions of CCL2, CCL3, CCL5, IL-1β, TNF-α, IL-6, ICAM-1, iNOS, and α-SMA in HSC-T6 cells.Our results demonstrated that Tan IIA decreased LPS-induced HSC activation.

  11. Non-perturbative scalar potential in type IIA strings on rigid CY

    CERN Document Server

    Alexandrov, Sergei; Wakimoto, Yuki

    2016-01-01

    We consider a class of flux compactifications of type IIA strings on rigid Calabi-Yau manifolds, preserving N=2 local supersymmetry in four dimensions. Using an exact D-instanton corrected metric on the hypermultiplet moduli space, we derive a non-perturbative potential of all scalar fields. Applying this potential to moduli stabilization, we find a discrete set of exact vacua for axions. At these critical points, the stability problem is decoupled into two subspaces spanned by the axions and the other fields (dilaton and Kahler moduli), respectively. Whereas the stability of the axions is easily achieved, numerical analysis shows instabilities in the second subspace.

  12. Examination of Lactic Acid Bacteria to Secretion of Bacteriocins

    Directory of Open Access Journals (Sweden)

    Maira Urazova

    2014-01-01

    Full Text Available Introduction: Bacteriocins produced by lactic acid bacteria (LAB have the potential to cover a very broad field of applications, including the food industry and the medical sector. In the food industry, bacteriocinogenic LAB strains can be used as starter cultures, co-cultures, and bioprotective cultures, which would be used to improve food quality and safety. In the medical sector, bacteriocins of probiotic LAB might play a role in interactions, which take place in human gastrointestinal tract, and contribute to gut health. The aim of this study was the examine the effect of LAB antimicrobial activity. Methods: LAB were isolated from different commercial and home made products, such as kazy and sour cream. To screen for bacteriocin producing LAB, we used an agar diffusion bioassay, described in a previous study by Dr. Yang, with three modifications in cell-free supernatant (CFS. First we had a clear supernatant, second we adjusted the CFS to pH 6.0 to eliminate acids antimicrobial effects, and third the CFS pH 6.0 was treated with catalase to exclude the action of H2O2 and confirm action of bacteriocin-like substances. Pathogenic S.marcescens, E. coli, S.aureus cultures were used as indicators. Results: Screening of 95 strains of LAB through deferred antagonism to six indicator cultures showed that all of the selected strains had a high value of antibacterial activity. However, CFS of only 50 strains retained their antimicrobial activity, and 10 of them lost this activity in the second modification of CFS with pH 6.0 to test culture S.marcescens, which confirmed the acidic nature of antimicrobial activity of CFS. Lb.rhamnosus (P-1, Lb.fermentum (N-6, and Lc.lactis (7M lost antibacterial activity in the presence of the catalase. All modifications of CFS of three strains: Lb.pentosus (16al, Lb.pentosus (P-2, and Pediococcusacidilactici (8 retained inhibitory activity to E.coli and S. aureus. Supernatants of only Lactococcusgarvieae (10a and

  13. Neuron Regeneration and Proliferation Effects of Danshen and Tanshinone IIA

    Directory of Open Access Journals (Sweden)

    Jui-Lung Shen

    2011-01-01

    Full Text Available This study evaluates the proliferative effects of danshen and its monomer extract, tanshinone IIA, on Schwann cell proliferation. A piece of silicone rubber was guided across a 15-mm gap in the sciatic nerve of a rat. This nerve gap was then filled with different concentrations of danshen (0–100 mg/mL. The results showed that danshen increased the expressions of uPA, cyclin D1, E and ERK, JNK, and P38 MAP kinases via the FGF-2 signaling pathway in a dose-dependent manner. RSC96, Schwann cells were also administered with danshen (0, 20, 40, 60, 80, and 100 μg/mL and tanshinone IIA (0, 2, 4, 6, 8, and 10 μg/mL. In lower concentrations, danshen and tanshinone IIA exhibited an apparent effect on Schwann cells. Similar effects were also demonstrated in the FGF-2-uPA regulating cascade and cell cycle proliferative protein results. Schwann cell migration was elevated as well. We used MAPK-signaling chemical inhibitors and identified the proliferative effects of danshen and tanshinone IIA as MAPK-signaling dependent. The results from the in vitro systems indicate that danshen and tanshinone IIA can be used to induce Schwann cell proliferation, and in vivo results potentially suggest that danshen and tanshinone IIA might enhance neuron regeneration.

  14. Antagonistic activity expressed by Shigella sonnei: identification of a putative new bacteriocin

    Directory of Open Access Journals (Sweden)

    Mireille Angela Bernardes Sousa

    2013-09-01

    Full Text Available Bacteriocins are antibacterial, proteinaceous substances that mediate microbial dynamics. Bacteriocin production is a highly disseminated property among all major lineages of bacteria, including Shigella. In this paper, we addressed the purification and characterisation of a bacteriocin produced by a Shigella sonnei strain (SS9 isolated from a child with acute diarrhoea. The substance was purified through ammonium-sulphate precipitation and sequential steps of chromatography. The intracellular fraction obtained at 75% ammonium sulphate maintained activity following exposure to pH values from 1-11 and storage at -80ºC for more than two years and was inactivated by high temperatures and proteases. The molecular mass of the purified bacteriocin was determined by mass spectrometry to be 18.56 kDa. The N-terminal sequence of the bacteriocin did not match any other antibacterial proteins described. A putative new bacteriocin produced by S. sonnei has been detected. This bacteriocin may represent a newly described protein or a previously described protein with a newly detected function. Considering that SS9 expresses antagonism against other diarrhoeagenic bacteria, the bacteriocin may contribute to S. sonnei virulence and is potentially applicable to either preventing or controlling diarrhoeal disease.

  15. Incidence of Bacteriocins Produced by Food-Related Lactic Acid Bacteria Active towards Oral Pathogens

    Directory of Open Access Journals (Sweden)

    Konstantinos Papadimitriou

    2013-02-01

    Full Text Available In the present study we investigated the incidence of bacteriocins produced by 236 lactic acid bacteria (LAB food isolates against pathogenic or opportunistic pathogenic oral bacteria. This set of LAB contained several strains (≥17% producing bacteriocins active against food-related bacteria. Interestingly only Streptococcus macedonicus ACA-DC 198 was able to inhibit the growth of Streptococcus oralis, Streptococcus sanguinis and Streptococcus gordonii, while Lactobacillus fermentum ACA-DC 179 and Lactobacillus plantarun ACA-DC 269 produced bacteriocins solely against Streptococcus oralis. Thus, the percentage of strains that were found to produce bacteriocins against oral bacteria was ~1.3%. The rarity of bacteriocins active against oral LAB pathogens produced by food-related LAB was unexpected given their close phylogenetic relationship. Nevertheless, when tested in inhibition assays, the potency of the bacteriocin(s of S. macedonicus ACA-DC 198 against the three oral streptococci was high. Fourier-transform infrared spectroscopy combined with principal component analysis revealed that exposure of the target cells to the antimicrobial compounds caused major alterations of key cellular constituents. Our findings indicate that bacteriocins produced by food-related LAB against oral LAB may be rare, but deserve further investigation since, when discovered, they can be effective antimicrobials.

  16. Coculture-inducible bacteriocin biosynthesis of different probiotic strains by dairy starter culture Lactococcus lactis

    OpenAIRE

    Blaženka Kos; Jasna Beganović; Lina Jurašić; Martina Švađumović; Andreja Leboš Pavunc; Ksenija Uroić; Jagoda Šušković

    2011-01-01

    Bacteriocins produced by probiotic strains effectively contribute to colonization ability of probiotic strains and facilitate their establishment in the competitive gut environment and also protect the gut from gastrointestinal pathogens. Moreover, bacteriocins have received considerable attention due to their potential application as biopreservatives, especially in dairy industry. Hence, the objective of this research was to investigate antimicrobial activity of probiotic strains Lactobacill...

  17. Genome sequence of the bacteriocin-producing oral probiotic Streptococcus salivarius strain M18.

    Science.gov (United States)

    Heng, Nicholas C K; Haji-Ishak, Nurul S; Kalyan, Alaina; Wong, Andrew Y C; Lovric, Marija; Bridson, Joanna M; Artamonova, Julia; Stanton, Jo-Ann L; Wescombe, Philip A; Burton, Jeremy P; Cullinan, Mary P; Tagg, John R

    2011-11-01

    Streptococcus salivarius is a Gram-positive bacterial commensal and pioneer colonizer of the human oral cavity. Many strains produce ribosomally synthesized proteinaceous antibiotics (bacteriocins), and some strains have been developed for use as oral probiotics. Here, we present the draft genome sequence of the bacteriocin-producing oral probiotic S. salivarius strain M18. PMID:22038965

  18. Production, purification and characterization of bacteriocin from Lactobacillus murinus AU06 and its broad antibacterial spectrum

    Institute of Scientific and Technical Information of China (English)

    Sivaramasamy Elayaraja; Neelamegam Annamalai; Packiyam Mayavu; Thangavel Balasubramanian

    2014-01-01

    Objective: To study the production, purification and characterization of bacteriocin fromLactobacillus murinus against fish pathogens.Methods:AU06 isolated from marine sediments and its broad spectrum of inhibition bacteriocin. In addition, purified bacteriocin was tested for its antimicrobial activity against fish pathogens.Results:In the present study, the bacteriocin production was found to be higher at 35 °C, pH The selected strain was used in production, purification and characterized of 6.0 and was purified to 4.74 fold with 55. 38 U/mg of specific activity with the yield of 28.92%. The molecular weight of the purified bacteriocin was estimated as 21 kDa. The purified bacteriocin exhibited complete inactivation of antimicrobial activity when treated with proteinase K, pronase, chymotrypsin, trypsin, pepsin and papain. The purified bacteriocin exhibited broad inhibitory spectrum against both Gram positive and negative bacteria.Conclusions:It is concluded that the ability of bacteriocin in inhibiting a wide-range of pathogenic bacteria is of potential interest for food safety and may have future applications in food preservative.

  19. Prinsip Penyelenggaraan Higiene Sanitasi Makanan Dan Tingkat Pengetahuan Serta Sikap Penjamah Makanan Di Lembaga Permasyarakatan Kelas Iia Binjai Tahun 2013

    OpenAIRE

    Aswita, Yulia

    2015-01-01

    The food handlers is a workerhandling food, both in preparing, processing, transporting and storing the food presentation. Processing personnel who provide service agencies that occupy specific (dormitories, orphanages, jails, etc). It is necessary for discussion to find out the attitude anf knowledge of food handlers in prison the class IIA Binjai. The purpose of this study is to get an overview of the state of hygiene and sanitation of food attitudes and knowledges of food handlers in p...

  20. Epidemiology and genetic characterization of hepatitis A virus genotype IIA.

    Science.gov (United States)

    Desbois, Delphine; Couturier, Elisabeth; Mackiewicz, Vincent; Graube, Arielle; Letort, Marie-José; Dussaix, Elisabeth; Roque-Afonso, Anne-Marie

    2010-09-01

    Three hepatitis A virus (HAV) genotypes, I, II, and III, divided into subtypes A and B, infect humans. Genotype I is the most frequently reported, while genotype II is hardly ever isolated, and its genetic diversity is unknown. From 2002 to 2007, a French epidemiological survey of HAV identified 6 IIA isolates, mostly from patients who did not travel abroad. The possible African origin of IIA strains was investigated by screening the 2008 mandatory notification records of HAV infection: 171 HAV strains from travelers to West Africa and Morocco were identified. Genotyping was performed by sequencing of the VP1/2A junction in 68 available sera. Entire P1 and 5' untranslated regions of IIA strains were compared to reference sequences of other genotypes. The screening retrieved 5 imported IIA isolates. An additional autochthonous case and 2 more African cases were identified in 2008 and 2009, respectively. A total of 14 IIA isolates (8 African and 6 autochthonous) were analyzed. IIA sequences presented lower nucleotide and amino acid variability than other genotypes. The highest variability was observed in the N-terminal region of VP1, while for other genotypes the highest variability was observed at the VP1/2A junction. Phylogenetic analysis identified 2 clusters, one gathering all African and two autochthonous cases and a second including only autochthonous isolates. In conclusion, most IIA strains isolated in France are imported by travelers returning from West Africa. However, the unexplained contamination mode of autochthonous cases suggests another, still to be discovered geographical origin or a French reservoir to be explored. PMID:20592136

  1. Bacteriocins: exploring alternatives to antibiotics in mastitis treatment

    Directory of Open Access Journals (Sweden)

    Reneé Pieterse

    2010-10-01

    Full Text Available 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.

  2. THE IMPORTANCE OF BACTERIOCINS IN MEAT AND MEAT PRODUCTS

    Directory of Open Access Journals (Sweden)

    Meltem SERDAROĞLU

    2000-03-01

    Full Text Available There is an increasing consumer demand for food products which are free of chemical additives, reduced in salt and processed as little as possible. These minimally processed foods require special application to assure their microbiological safety. The use of microorganisms and enzymes for food preservatives is called biopreservation. The most important group of microorganisms with antimicrobial effect used in the production of foods is the lactic acid bacteria. In meats although lactic acid bacteria constitue apart of the initial microflora, they become dominant during the processing of meats. In this research bacteriocins of lactic acid bacteria and their usage in meat and meat products for biopreservation are discussed.

  3. Antibacterial Activity and Purification of Bacteriocin Produced by Brevibacillus laterosporus SA14

    Directory of Open Access Journals (Sweden)

    On-anong SOMSAP

    2016-01-01

    Full Text Available A bacteriocin producing strain, Brevibacillus laterosporus SA14 was isolated from an air sample at Walailak University, Thailand. The antibacterial activity of Brev. laterosporus SA14 was assayed by the cross streak and agar well diffusion method. Results from the cross streak method showed that it can inhibit both Gram positive and Gram negative bacteria. While results from the agar well diffusion method showed that Micrococcus luteus TISTR884 exhibited higher sensitivity to bacteriocin produced by Brev. laterosporus SA14 than other indicator strains. The highest amount of bacteriocin produced by Brev. laterosporus SA14 was detected during day 8 to day 10 of incubation. The crude protein exhibited bacteriocin activity of 800 AU/ml and did not affect cell membranes of Staphylococcus aureus TISTR516 and MRSA142. The bacteriocin activity increased from 25 AU/ml in supernatant to 800 AU/ml in crude protein after ammonium sulfate precipitation, corresponding to 88 % recovery and 32-fold purification. The fraction number was 39 to 41 from the Sp-sepharose fast flow column chromatography expressed highest bacteriocin activity with 44.8 % recovery and 128-fold purification. The partially purified bacteriocin was revealed as a single band on SDS-PAGE gel with a molecular weight of 6.9 kDa. The active fractions were finally pooled and purified by Reverse Phase High Performance Liquid Chromatography (RP-HPLC. The result showed a single peak (retention time of 3.466 min with antibacterial activity.

  4. Isolation of Lactobacillus salivarius from Children and Purification of Bacteriocin to Inhibition Cancer Cell in Vitro

    Directory of Open Access Journals (Sweden)

    Waleed K. M. Al-Tememy

    2011-01-01

    Full Text Available Bacteria being used to make anticancer agents could provide an extra source of lead compounds for the pharmaceutical industry.  Bacterium Lactobacillus salivarius produce compounds that selectively inhibit growth of human cancer cells Lactobacillus salivarius naturally produces a compound called Bacteriocins.  Bacteriocins are bacterial proteins produced to prevent the growth of competing microorganisms in a particular biological niche and we can use it as antineoplastic. The aim of this study was to isolate bacteriocin produced by lactic acid bacteria. A preparation of bacteriocin from a strain Lactobacillus salivarius has long been shown to have antineoplastic activity against a variety of human tumor and animal tumor cell lines in vitro. A total of 60 LAB  were isolated from children stool 45 isolate showed a clear antimicrobial activity against indicator strain Streptococcus aureus and by used sodium phosphate buffer (pH8 from an 80% ammonium sulfate precipitate. The inhibition  activity was determent by well diffusion assay method technique, Bacteriocin purification processes were carried out by using ion-exchange (Trisacryl SP and gel filtration chromatography (Sephacryl – S300. The apparent molecular mass of partially purified bacteriocin was 15. 848 kDa,  Cell Culture was maintained in RPMI 1640 medium supplemented with 10% (vol/vol fetal calf serum,  Cytotoxicity of bacteriocin was assessed on human cell line (RD and animal cell line (MDCK cell viability after incubation for 48 h in medium containing 500AU/ml (1.15 mg/ml. Both cell types used in this study were sensitive to bacteriocin and the bacteriocin appeared to inhibit proliferation of tumor cell line. The animal cell line was more sensitivity than human cell line.

  5. One-phonon absorption by type IIa diamonds

    Science.gov (United States)

    Kiflawi, I.; Welbourn, C. M.; Woods, G. S.

    1993-02-01

    Brown type IIa diamonds have been found to exhibit a very weak one-phonon infrared absorption that begins near the Raman energy at 1332cm -1, and increases, with decreasing wavenumber, to a maximum at 1016cm -1 with a shoulder on the high-wavenumber side at about 1050cm -1. A colourless type IIa specimen showed an even weaker absorption beginning again near 1332cm -1 and increasing to show two maxima near 1100cm -1 and 1000cm -1. These specimen also showed birefringence patterns between crossed polars that are indicative of plastic deformation. It is suggested that the infrared absorptions are caused by dislocations.

  6. An evaluation and partial characterization of a bacteriocin produced by Lactococcus lactis subsp lactis ST1 isolated from goat milk.

    Science.gov (United States)

    Taheri, Parinaz; Samadi, Nasrin; Ehsani, Mohammad Reza; Khoshayand, Mohammad Reza; Jamalifar, Hossein

    2012-10-01

    A bacteriocin-like inhibitory substance producing Lactococcus lactis subsp lactis strain, ST1, isolated from goat milk of Iranian origin and with broad spectrum of activity and desirable technical properties was used for evaluating some futures of bacteriocin inhibitory activity. Cell growth and bacteriocin production studies were carried out in MRS medium incubated statically under uncontrolled pH condition. The antibacterial activity presented a primary metabolite pattern and showed a rapid decrease at the stationary phase. Microaerobiosis and capnophily growth conditions resulted in higher bacteriocin production while aerobiosis showed negative effect on both cell growth and bacteriocin production. Bacteriocin production, on the other hand, was favored in MRS broth (pH; 6.5) inoculated with 0.1 ml l(-1) fresh culture when incubation was carried out at 30 °C. This indicated that the conditions resulted in higher levels of growth were frequently favoring bacteriocin production by ST1 as well. Decrease in activity, at the stationary growth phase, was much pronounced in favored growth condition. Nutrient depletion, deferent effect of low pH on bacteriocin production and/or protein degradation seemed more responsible for this phenomenon. The study also provided further data on new method for bacteriocin release from the cell wall of producer. It was clearly shown that both heating and ultrasound shock for 5 min at pH 2 could increase bacteriocin activity significantly. The release was more pronounced in the presence of 0.5% Tween80. PMID:24031976

  7. An evaluation and partial characterization of a bacteriocin produced by Lactococcus lactis subsp lactis ST1 isolated from goat milk

    Directory of Open Access Journals (Sweden)

    Parinaz Taheri

    2012-12-01

    Full Text Available A bacteriocin-like inhibitory substance producing Lactococcus lactis subsp lactis strain, ST1, isolated from goat milk of Iranian origin and with broad spectrum of activity and desirable technical properties was used for evaluating some futures of bacteriocin inhibitory activity. Cell growth and bacteriocin production studies were carried out in MRS medium incubated statically under uncontrolled pH condition. The antibacterial activity presented a primary metabolite pattern and showed a rapid decrease at the stationary phase. Microaerobiosis and capnophily growth conditions resulted in higher bacteriocin production while aerobiosis showed negative effect on both cell growth and bacteriocin production. Bacteriocin production, on the other hand, was favored in MRS broth (pH; 6.5 inoculated with 0.1 ml l-1 fresh culture when incubation was carried out at 30 °C. This indicated that the conditions resulted in higher levels of growth were frequently favoring bacteriocin production by ST1 as well. Decrease in activity, at the stationary growth phase, was much pronounced in favored growth condition. Nutrient depletion, deferent effect of low pH on bacteriocin production and/or protein degradation seemed more responsible for this phenomenon. The study also provided further data on new method for bacteriocin release from the cell wall of producer. It was clearly shown that both heating and ultrasound shock for 5 min at pH 2 could increase bacteriocin activity significantly. The release was more pronounced in the presence of 0.5% Tween80.

  8. Purification Techniques of Bacteriocins from Lactic Acid Bacteria and Other Gram-Positive Bacteria

    Science.gov (United States)

    Saavedra, Lucila; Sesma, Fernando

    The search for new antimicrobial peptides produced by lactic acid ­bacteria and other Gram-positive microorganisms has become an interesting field of research in the past decades. The fact that bacteriocins are active against numerous foodborne and human pathogens, are produced by generally regarded as safe (GRAS) microorganisms, and are readily degraded by proteolytic host systems makes them attractive candidates for biotechnological applications. However, before suggesting or choosing a new bacteriocin for future technology developments, it is necessary to elucidate its biochemical structure and its mode of action, which may be carried out once the bacteriocin is purified to homogeneity. This chapter focuses on describing the main strategies used for the purification of numerous bacteriocins.

  9. Activity of two Streptococcus mutans bacteriocins in the presence of saliva, levan, and dextran.

    Science.gov (United States)

    Delisle, A L

    1976-01-01

    The extracellular dextrans produced from sucrose by Streptococcus mutans strains BHT and GS-5 did not prevent the synthesis or release of active bacteriocins by these two strains. In addition, several streptococci that were genetically sensitive to these bacteriocins, and that could synthesize a variety of extracellular dextrans and levans from sucrose, remained phenotypically sensitive when grown in the presence of sucrose. Bacteriocin activity was not altered by treatment with high-molecular-weight dextran or by human saliva. The bacteriocins produced by, and active against, S. mutans thus appear to be capable of acting in vivo and may play a role in regulating the bacterial ecology of the oral cavity. Images PMID:4376

  10. Bacteriocinogenic Lactococcus lactis subsp. lactis DF04Mi isolated from goat milk: characterization of the bacteriocin.

    Science.gov (United States)

    Furtado, Danielle N; Todorov, Svetoslav D; Landgraf, Mariza; Destro, Maria T; Franco, Bernadette D G M

    2014-01-01

    Lactic acid bacteria capable of producing bacteriocins and presenting probiotic potential open innovative technological applications in the dairy industry. In this study, a bacteriocinogenic strain (Lactococcus lactis subsp. lactis DF4Mi) was isolated from goat milk, and studied for its antimicrobial activity. The bacteriocin presented a broad spectrum of activity, was sensitive to proteolytic enzymes, resistant to heat and pH extremes, and not affected by the presence of SDS, Tween 20, Tween 80, EDTA or NaCl. Bacteriocin production was dependent on the components of the culture media, especially nitrogen source and salts. When tested by PCR, the bacteriocin gene presented 100% homology to nisin Z gene. These properties indicate that this L. lactis subsp. lactis DF4Mi can be used for enhancement of dairy foods safety and quality. PMID:25763065

  11. Bacteriocinogenic Lactococcus lactis subsp. lactis DF04Mi isolated from goat milk: characterization of the bacteriocin

    Directory of Open Access Journals (Sweden)

    Danielle N. Furtado

    2014-12-01

    Full Text Available Lactic acid bacteria capable of producing bacteriocins and presenting probiotic potential open innovative technological applications in the dairy industry. In this study, a bacteriocinogenic strain (Lactococcus lactis subsp. lactis DF4Mi was isolated from goat milk, and studied for its antimicrobial activity. The bacteriocin presented a broad spectrum of activity, was sensitive to proteolytic enzymes, resistant to heat and pH extremes, and not affected by the presence of SDS, Tween 20, Tween 80, EDTA or NaCl. Bacteriocin production was dependent on the components of the culture media, especially nitrogen source and salts. When tested by PCR, the bacteriocin gene presented 100% homology to nisin Z gene. These properties indicate that this L. lactis subsp. lactis DF4Mi can be used for enhancement of dairy foods safety and quality.

  12. Japanese contribution to IAEA INTOR workshop, phase IIA

    International Nuclear Information System (INIS)

    This report corresponds to Chapter XI of Japanese contribution report to IAEA INTOR Workshop, Phase IIA. This report describes a new concept with a significant reduction in the device size and cost while maintaing the plasma size and performance from Phase I. This concept can be realized mainly by mitigating the allowable field ripple from 0.75% to 1.2%. (author)

  13. Japanese contributions to IAEA INTOR workshop, phase IIA

    International Nuclear Information System (INIS)

    This report corresponds to Chapter X of Japanese contribution report to IAEA INTOR workshop, Phase IIA. Transitional analysis of electromagnetic phenomenon which includes joule heat depositions in supper conducting coil system, electromagnetic force acting on torus components and shell effects for stabilizing plasma positional instability, is carried out. (author)

  14. Bacteriocins: molecules of fundamental impact on the microbial ecology and potential food biopreservatives

    OpenAIRE

    Evandro Leite de Souza; Clemilson Antonio da Silva; Cristina Paiva de Sousa

    2005-01-01

    Bacteriocins are proteic molecules synthesized for various lineages of Gram-positive and Gram-negative bacteria when exposed to stressful conditions. Bacteriocins have been characterized as molecules of high antimicrobial property even at low concentrations, provoking the microbial survival inhibition by antibiosis. These substances have their synthesis mediated for genetic mechanisms and develop their lethal action on the microbial cell by multiples mechanisms that can act of isolated or con...

  15. Microcins from Enterobacteria: On the Edge Between Gram-Positive Bacteriocins and Colicins

    Science.gov (United States)

    Rebuffat, Sylvie

    Most bacteria and archaea produce gene-encoded antimicrobial peptides/proteins called bacteriocins, which are secreted by the producing bacteria to compete against other microorganisms in a given niche. They are considered important mediators of intra- and interspecies interactions and therefore a factor in ­maintaining the microbial diversity and stability. They are ribosomally synthesized, and most of them are produced as inactive precursor proteins, which in some cases are further enzymatically modified. Bacteriocins generally exert potent antibacterial activities directed against bacterial species closely related to the producing bacteria. Bacteriocins are abundant and diverse in Gram-negative and Gram-positive bacteria. This chapter focuses on colicins and microcins from enterobacteria (mainly Escherichia coli) and on bacteriocins from lactic acid bacteria (LAB). Microcins are the lower-molecular-mass bacteriocins produced by Gram-negative bacteria with a repertoire of only 14 representatives. They form a very restricted family of bacteriocins, compared to the huge family of LAB bacteriocins that is constituted of several hundreds of peptides, with which microcins share common characteristics. Nevertheless, microcins also show similarities, particularly in their uptake mechanisms, with the higher-molecular-mass colicins, also produced by E. coli strains. On the edge between LAB bacteriocins and colicins, microcins appear to combine highly efficient strategies developed by both Gram-positive and Gram-negative bacteria at different levels, including uptake, translocation, killing of target cells, and immunity of the producing bacteria, making them important actors of bacterial competitions and fascinating models for novel concepts toward antimicrobial strategies and against resistance mechanisms.

  16. Bacteriocinogenic Lactococcus lactis subsp. lactis DF04Mi isolated from goat milk: Characterization of the bacteriocin

    OpenAIRE

    Furtado, Danielle N.; Todorov, Svetoslav D.; Mariza Landgraf; Maria T. Destro; Franco, Bernadette D.G.M.

    2015-01-01

    Lactic acid bacteria capable of producing bacteriocins and presenting probiotic potential open innovative technological applications in the dairy industry. In this study, a bacteriocinogenic strain (Lactococcus lactis subsp. lactis DF4Mi) was isolated from goat milk, and studied for its antimicrobial activity. The bacteriocin presented a broad spectrum of activity, was sensitive to proteolytic enzymes, resistant to heat and pH extremes, and not affected by the presence of SDS, Tween 20, Tween...

  17. Effect of bacteriocin from Lactobacillus sp. Var. SCG 1223 on microbiological quality of fresh meat

    OpenAIRE

    Sri Usmiati; Miskiyah; Rarah R.A.M.

    2009-01-01

    Inhibition technology of microorganism on meat can be done biologically and chemically. Biologically, inhibition to microbe can be conducted by addition antimicrobe, for example bacteriocin that have character as biopreservative. The aim of this research was to study the microbiological quality of fresh meat with bacteriocin isolated from Lactobacillus sp. SCG 1223 storaged at certain addition and temperature with different storage time. This experiment was done based on Completely of Random ...

  18. Diverse Ecological Strategies Are Encoded by Streptococcus pneumoniae Bacteriocin-Like Peptides.

    Science.gov (United States)

    Miller, Eric L; Abrudan, Monica I; Roberts, Ian S; Rozen, Daniel E

    2016-01-01

    The opportunistic pathogen Streptococcus pneumoniae is commonly carried asymptomatically in the human nasopharynx. Due to high rates of cocolonization with other pneumococcus strains, intraspecific competitive interactions partly determine the carriage duration of strains and thereby their potential to cause disease. These interactions may be mediated by bacteriocins, such as the type IIb bacteriocins encoded by the blp (bacteriocin-like peptide) locus. To understand blp diversity and evolution, we undertook a bioinformatic analysis of 4,418 pneumococcal genomes, including 168 newly sequenced genomes. We describe immense variation at all levels of genomic organization: Gene presence/absence, gene order, and allelic diversity. If we make the extreme and naive hypothesis that assumes all genes in this operon can assort randomly, this variation could lead to 10(15) distinct bacteriocin-related phenotypes, each potentially representing a unique ecological strategy; however, we provide several explanations for why this extreme is not realized. Although rarefaction analysis indicates that the number of unique strategies is not saturated, even after sampling thousands of genomes, we show that the variation is neither unbounded nor random. We delimit three bacteriocin groups, which contain group-specific bacteriocins, immunity genes, and blp operon gene order, and argue that this organization places a constraint on realized ecological strategies. We additionally show that ecological strategy diversity is significantly constrained by pneumococcal phylogeny and clonal structure. By examining patterns of association between alleles within the blp operon, we show that bacteriocin genes, which were believed to function in pairs, can be found with a broad diversity of partner alleles and immunity genes; this overall lack of allelic fidelity likely contributes to the fluid structure of this operon. Our results clarify the diversity of antagonistic ecological strategies in the

  19. Bacteriocin Production with Lactobacillus amylovorus DCE 471 Is Improved and Stabilized by Fed-Batch Fermentation

    OpenAIRE

    Callewaert, Raf; De Vuyst, Luc

    2000-01-01

    Amylovorin L471 is a small, heat-stable, and hydrophobic bacteriocin produced by Lactobacillus amylovorus DCE 471. The nutritional requirements for amylovorin L471 production were studied with fed-batch fermentations. A twofold increase in bacteriocin titer was obtained when substrate addition was controlled by the acidification rate of the culture, compared with the titers reached with constant substrate addition or pH-controlled batch cultures carried out under the same conditions. An inter...

  20. Elimination of Listeria monocytogenes in sausage meat by combination treatment: Radiation and radiation-resistant bacteriocins

    International Nuclear Information System (INIS)

    Two new bacteria were isolated from human feces and were designated MT 104 and MT 162. They were able to produce bacteriocins that are active against five strains of Listeria monocytogenes. Bacteriocins produced by these isolated strains had 100% and 82.35% residual activity when they were treated by gamma radiation at doses of 4 and 40 kGy, respectively. A reduction of 1.0, 1.5 and 3 log CFU/g of L. monocytogenes was observed in sausage meat when treated with bacteriocins from MT 104, MT 162, and nisin, respectively. For synergic effect, the D10 value in presence of the bacteriocins produced by MT 104 showed a 1.08 fold increased relative sensitivity of L. monocytogenes as compared to control after 5 days. The highest synergic effect was observed in presence of nisin which led to 1.61 fold increased relative sensitivity. Combined treatments with nisin and γ-irradiation showed a synergic antimicrobial effect in meat after 24 h and 5 days of storage. A synergic effect was observed only after 5 days at 4 °C for the bacteriocin from MT 104, as compared to the bacteriocin produced by MT 162 that had only an additive antimicrobial effect in all conditions.

  1. Elimination of Listeria monocytogenes in sausage meat by combination treatment: Radiation and radiation-resistant bacteriocins

    Science.gov (United States)

    Turgis, Mélanie; Stotz, Viviane; Dupont, Claude; Salmieri, Stéphane; Khan, Ruhul A.; Lacroix, Monique

    2012-08-01

    Two new bacteria were isolated from human feces and were designated MT 104 and MT 162. They were able to produce bacteriocins that are active against five strains of Listeria monocytogenes. Bacteriocins produced by these isolated strains had 100% and 82.35% residual activity when they were treated by gamma radiation at doses of 4 and 40 kGy, respectively. A reduction of 1.0, 1.5 and 3 log CFU/g of L. monocytogenes was observed in sausage meat when treated with bacteriocins from MT 104, MT 162, and nisin, respectively. For synergic effect, the D10 value in presence of the bacteriocins produced by MT 104 showed a 1.08 fold increased relative sensitivity of L. monocytogenes as compared to control after 5 days. The highest synergic effect was observed in presence of nisin which led to 1.61 fold increased relative sensitivity. Combined treatments with nisin and γ-irradiation showed a synergic antimicrobial effect in meat after 24 h and 5 days of storage. A synergic effect was observed only after 5 days at 4 °C for the bacteriocin from MT 104, as compared to the bacteriocin produced by MT 162 that had only an additive antimicrobial effect in all conditions.

  2. Bacteriocins produced by L. fermentum and L .acidophilus can inhibit cephalosporin resistant E .coli.

    Directory of Open Access Journals (Sweden)

    Saba Riaz

    2010-10-01

    Full Text Available Reemerging infections occur due to resistant bacteria. Such infections create restrictions for clinicians and microbiologists in drug selection. Such problems demand new strategies for solution. Use of bacteriocins for this purpose may be fruitful. In the present research work, the inhibitory effects of bactericins on cephalosporin resistant Escherichia coli are used as model system for the control of antibiotic resistant pathogenic bacteria. Cephalosporin resistant Escherichia coli strain was isolated from pus by using conventional methodology. For bacteriocin production, Lactobacilli strains were selected by using selective media. Out of seventy two strains isolated from yogurt, fecal materials of human, chick, parrot and cat, only two strains (strain 45 and strain 52 were found to produce bacteriocins having antimicrobial potential against cephalosporin resistant Escherichia coli. Biochemical characterization showed that strain 45 belonged to group of Lactobacillus fermentum and strain 52 to Lactobacillus acidophilus. Both strains showed maximum growth at 25°C and 35°C respectively. Suitable pH was 5.5 and 6.0 for Lactobacillus fermentum and Lactobacillus acidophilus respectively. Bacteriocins produced by both strains were found stable at 50, 75 and 100°C for 60min. Function of bacteriocin was also not disturbed due to change in pH. These findings suggest that bacteriocin produced by Lactobacillus fermentum and Lactobacillus acidophilus can be used for the infection control of cephalosporin resistant Escherichia coli.

  3. Bacteriocin from Bacillus subtilis as a novel drug against diabetic foot ulcer bacterial pathogens

    Institute of Scientific and Technical Information of China (English)

    Baby Joseph; Berlina Dhas; Vimalin Hena; Justin Raj

    2013-01-01

    Objective:To isolate and identify Bacillus subtilis (B. subtilis) from soil and to characterize and partially purify the bacteriocin. To evaluate the antimicrobial activity against four diabetic foot ulcer bacterial pathogens. Methods:Genotypic identification was done based on Bergey’s manual of systemic bacteriology. Antimicrobial susceptibility test was done by Kirby-Bauer disc diffusion method. Colonies were identified by colony morphology and biochemical characterization and also compared with MTCC 121 strain. Further identification was done by 16S rRNA sequencing. Inhibitory activities of partially purified bacteriocin on all the DFU isolates were done by agar well diffusion method. The strain was identified to produce bacteriocin by stab overlay assay. Bacteriocin was extracted by organic solvent extraction using chloroform, further purified by HPLC and physical, and chemical characterization was performed. Results: The four isolates showed high level of resistance to amoxyclav and sensitivity to ciprofloxacin. HPLC purification revealed that the extracts are bacteriocin. The phylogenetic tree analysis results showed that the isolate was 99%related to B. subtilis BSF01. The results reveled activity to all the four isolates and high level of activity was seen in case of Klebsiella sp. Conclusions:Partially purified bacteriocin was found to have antimicrobial activity against the four diabetic foot ulcer bacterial pathogens, which can thus be applied as a better drug molecule on further studies. The strain B. subtilis are found to be safe for use and these antimicrobial peptides can be used as an antimicrobial in humans to treat DFU bacterial pathogens.

  4. Streptococcal bacteriocins and the case for Streptococcus salivarius as model oral probiotics.

    Science.gov (United States)

    Wescombe, Philip A; Heng, Nicholas C K; Burton, Jeremy P; Chilcott, Chris N; Tagg, John R

    2009-09-01

    Members of the Gram-positive bacterial genus Streptococcus are a diverse collection of species inhabiting many body sites and range from benign, nonpathogenic species to those causing life-threatening infections. The streptococci are also prolific producers of bacteriocins, which are ribosomally synthesized proteinaceous antibiotics that kill or inhibit species closely related to the producer bacterium. With the emergence of bacterial resistance to conventional antibiotics, there is an impetus to discover, and implement, new and preferably 'natural' antibiotics to treat or prevent bacterial infections, a niche that bacterial interference therapy mediated by bacteriocins could easily fill. This review focuses on describing the diversity of bacteriocins produced by streptococci and also puts forth a case for Streptococcus salivarius, a nonpathogenic and numerically predominant oral species, as an ideal candidate for development as the model probiotic for the oral cavity. S. salivarius is a safe species that not only produces broad-spectrum bacteriocins but harbors bacteriocin-encoding (and bacteriocin-inducing) transmissible DNA entities (megaplasmids). PMID:19722837

  5. Optimization and partial characterization of bacteriocin produced by Lactobacillus bulgaricus -TLBFT06 isolated from Dahi.

    Science.gov (United States)

    Mahmood, Talat; Masud, Tariq; Ali, Sartaj; Abbasi, Kashif Sarfraz; Liaquat, Muhammad

    2015-03-01

    Lactobacillus bulgaricus is one of the predominant lactic acid bacteria of dahi, conferring technological and functional attributes. In the present study thirty dahi samples were investigated for bacteriocin producing L. bulgaricus. Fourteen different isolates were obtained and five were scrutinized for antibacterial activities against food born pathogens. Amongst, a strain TLB06FT was found to have a wide array of antibacterial activities against Gram positive and negative bacteria was selected for further characterization. Growth media optimization for this strain revealed maximum bacteriocin production on MRS media supplemented with glucose (2%), sodium chloride (1%), Tween-80 (0.5%) and yeast extract (1 %). In addition, optimization of growth conditions revealed maximum bacteriocin production at pH 5.5 and temperature of 30-37°C. Bacteriocin showed thermo stability at 90°C and remained highly active in the pH range of 3.5-7.5, inactive by protein catalyzing enzymes and showed no change in activity (800AumL(-1)) when treated with organic solvents and surfactants. The obtained bacteriocin was purified to 1600AU mL(-1) by ammonium sulfate precipitation (80%) by using dialyzing tubing. In the same way, a single peak was obtained by RP-HPLC having antibacterial activity of 6400AU mL(-1). Thus, wild strains of L. bulgaricus have great potential for the production new and novel type of bacteriocins. PMID:25730789

  6. Conjugal transfer and characterization of bacteriocin plasmids in group N (lactic acid) streptococci.

    Science.gov (United States)

    Neve, H; Geis, A; Teuber, M

    1984-01-01

    Thirteen bacteriocin-producing strains of group N (lactic acid) streptococci were screened for their potential to transfer this property by conjugation to Streptococcus lactis subsp. diacetylactis Bu2-60. Bacteriocin production in three strains was plasmid encoded as shown by conjugal transfer and by analysis of cured, bacteriocin-negative derivatives of the donor strains and the transconjugants. With Streptococcus cremoris strains 9B4 and 4G6 and S. lactis subsp. diacetylactis 6F7 as donors, bacteriocin-producing transconjugants were isolated with frequencies ranging from ca. 2 X 10(-2) to 2 X 10(-1) per recipient cell. Bacteriocin-producing transconjugants had acquired a 39.6-megadalton plasmid from the donor strains 9B4 and 4G6, and a 75-megadalton plasmid from the donor strain 6F7. As shown by restriction endonuclease analysis, the plasmids from strains 9B4 and 4G6 were almost identical. The plasmid from strain 6F7 yielded some additional fragments not present in the two other plasmids. In hybridization experiments any of the three plasmids strongly hybridized with each other and with some other bacteriocin but nontransmissible plasmids from other S. cremoris strains. Homology was also detected to a variety of cryptic plasmids in lactic acid streptococci. Images PMID:6321437

  7. Secretory Phospholipase A2-IIA and Cardiovascular Disease

    Science.gov (United States)

    Holmes, Michael V.; Simon, Tabassome; Exeter, Holly J.; Folkersen, Lasse; Asselbergs, Folkert W.; Guardiola, Montse; Cooper, Jackie A.; Palmen, Jutta; Hubacek, Jaroslav A.; Carruthers, Kathryn F.; Horne, Benjamin D.; Brunisholz, Kimberly D.; Mega, Jessica L.; van Iperen, Erik P.A.; Li, Mingyao; Leusink, Maarten; Trompet, Stella; Verschuren, Jeffrey J.W.; Hovingh, G. Kees; Dehghan, Abbas; Nelson, Christopher P.; Kotti, Salma; Danchin, Nicolas; Scholz, Markus; Haase, Christiane L.; Rothenbacher, Dietrich; Swerdlow, Daniel I.; Kuchenbaecker, Karoline B.; Staines-Urias, Eleonora; Goel, Anuj; van 't Hooft, Ferdinand; Gertow, Karl; de Faire, Ulf; Panayiotou, Andrie G.; Tremoli, Elena; Baldassarre, Damiano; Veglia, Fabrizio; Holdt, Lesca M.; Beutner, Frank; Gansevoort, Ron T.; Navis, Gerjan J.; Mateo Leach, Irene; Breitling, Lutz P.; Brenner, Hermann; Thiery, Joachim; Dallmeier, Dhayana; Franco-Cereceda, Anders; Boer, Jolanda M.A.; Stephens, Jeffrey W.; Hofker, Marten H.; Tedgui, Alain; Hofman, Albert; Uitterlinden, André G.; Adamkova, Vera; Pitha, Jan; Onland-Moret, N. Charlotte; Cramer, Maarten J.; Nathoe, Hendrik M.; Spiering, Wilko; Klungel, Olaf H.; Kumari, Meena; Whincup, Peter H.; Morrow, David A.; Braund, Peter S.; Hall, Alistair S.; Olsson, Anders G.; Doevendans, Pieter A.; Trip, Mieke D.; Tobin, Martin D.; Hamsten, Anders; Watkins, Hugh; Koenig, Wolfgang; Nicolaides, Andrew N.; Teupser, Daniel; Day, Ian N.M.; Carlquist, John F.; Gaunt, Tom R.; Ford, Ian; Sattar, Naveed; Tsimikas, Sotirios; Schwartz, Gregory G.; Lawlor, Debbie A.; Morris, Richard W.; Sandhu, Manjinder S.; Poledne, Rudolf; Maitland-van der Zee, Anke H.; Khaw, Kay-Tee; Keating, Brendan J.; van der Harst, Pim; Price, Jackie F.; Mehta, Shamir R.; Yusuf, Salim; Witteman, Jaqueline C.M.; Franco, Oscar H.; Jukema, J. Wouter; de Knijff, Peter; Tybjaerg-Hansen, Anne; Rader, Daniel J.; Farrall, Martin; Samani, Nilesh J.; Kivimaki, Mika; Fox, Keith A.A.; Humphries, Steve E.; Anderson, Jeffrey L.; Boekholdt, S. Matthijs; Palmer, Tom M.; Eriksson, Per; Paré, Guillaume; Hingorani, Aroon D.; Sabatine, Marc S.; Mallat, Ziad; Casas, Juan P.; Talmud, Philippa J.

    2013-01-01

    Objectives This study sought to investigate the role of secretory phospholipase A2 (sPLA2)-IIA in cardiovascular disease. Background Higher circulating levels of sPLA2-IIA mass or sPLA2 enzyme activity have been associated with increased risk of cardiovascular events. However, it is not clear if this association is causal. A recent phase III clinical trial of an sPLA2 inhibitor (varespladib) was stopped prematurely for lack of efficacy. Methods We conducted a Mendelian randomization meta-analysis of 19 general population studies (8,021 incident, 7,513 prevalent major vascular events [MVE] in 74,683 individuals) and 10 acute coronary syndrome (ACS) cohorts (2,520 recurrent MVE in 18,355 individuals) using rs11573156, a variant in PLA2G2A encoding the sPLA2-IIA isoenzyme, as an instrumental variable. Results PLA2G2A rs11573156 C allele associated with lower circulating sPLA2-IIA mass (38% to 44%) and sPLA2 enzyme activity (3% to 23%) per C allele. The odds ratio (OR) for MVE per rs11573156 C allele was 1.02 (95% confidence interval [CI]: 0.98 to 1.06) in general populations and 0.96 (95% CI: 0.90 to 1.03) in ACS cohorts. In the general population studies, the OR derived from the genetic instrumental variable analysis for MVE for a 1-log unit lower sPLA2-IIA mass was 1.04 (95% CI: 0.96 to 1.13), and differed from the non-genetic observational estimate (OR: 0.69; 95% CI: 0.61 to 0.79). In the ACS cohorts, both the genetic instrumental variable and observational ORs showed a null association with MVE. Instrumental variable analysis failed to show associations between sPLA2 enzyme activity and MVE. Conclusions Reducing sPLA2-IIA mass is unlikely to be a useful therapeutic goal for preventing cardiovascular events. PMID:23916927

  8. Exceptional generalised geometry for massive IIA and consistent reductions

    CERN Document Server

    Cassani, Davide; Petrini, Michela; Strickland-Constable, Charles; Waldram, Daniel

    2016-01-01

    We develop an exceptional generalised geometry formalism for massive type IIA supergravity. In particular, we construct a deformation of the generalised Lie derivative, which generates the type IIA gauge transformations as modified by the Romans mass. We apply this new framework to consistent Kaluza-Klein reductions preserving maximal supersymmetry. We find a generalised parallelisation of the exceptional tangent bundle on S^6, and from this reproduce the consistent truncation ansatz and embedding tensor leading to dyonically gauged ISO(7) supergravity in four dimensions. We also discuss closely related hyperboloid reductions, yielding a dyonic ISO(p,7-p) gauging. Finally, while for vanishing Romans mass we find a generalised parallelisation on S^d, d=4,3,2, leading to a maximally supersymmetric reduction with gauge group SO(d+1) (or larger), we provide evidence that an analogous reduction does not exist in the massive theory.

  9. Factors affecting production of an antilisterial bacteriocin by Carnobacterium piscicola strain A9b in laboratory media and model fish systems

    DEFF Research Database (Denmark)

    Himelbloom, B.; Nilsson, Lilian; Gram, Lone

    2001-01-01

    Aims: To investigate factors influencing bacteriocin production and bacteriocin stability of the bioprotective culture Carnobacterium piscicola strain A9b. Methods and Results: Maximum activity was obtained in MRS7 broth (MRS adjusted to pH 7.2), with or without glucose. No bacteriocin was produced...

  10. Synapsin IIa controls the reserve pool of glutamatergic synaptic vesicles

    OpenAIRE

    Gitler, Daniel; Cheng, Qing; Greengard, Paul; Augustine, George J.

    2008-01-01

    Synapsins regulate synaptic transmission by controlling the reserve pool of synaptic vesicles. Each of the three mammalian synapsin genes is subject to alternative splicing, yielding several isoforms whose roles are unknown. To investigate the function of these isoforms, we examined the synaptic effects of introducing each isoform into glutamatergic cultured hippocampal neurons from synapsin triple knock-out mice. Remarkably, we found that synapsin IIa was the only isoform that could rescue t...

  11. Proteolytic Characterization of Trimmed Beef Fermented Sausages Inoculated by Indonesian Probiotics: Lactobacillus plantarum IIA-2C12 and Lactobacillus acidophilus IIA-2B4

    Directory of Open Access Journals (Sweden)

    Dyah Nurul Afiyah

    2015-05-01

    Full Text Available Proteolysis is one of the most important biochemical changes affecting proteins during the ripening and preservation of fermented beef sausages. In this study, proteolytic activities of two Indonesian probiotics, Lactobacillus plantarum IIA-2C12 and Lactobacillus acidophilus IIA-2B4 used as starters in trimmed beef are investigated. IIA-2B4 used as starters in trimmed beef are investigated. L. plantarum IIA-2C12 and L. acidophilus displayed remarkable proteolytic activities against milk casein substrate, in which the activity of L. plantarum IIA-2C12 is higher than that of L. acidophilus IIA-2B4. Similar evidences were observed when proteolytic activities of both strains were visualized by using SDS-Page against meat sarcoplasmic proteins. The differences in the number of proteases encoded by the genomes of both starters might account for these differences. The activities of both strains were slightly reduced upon storage at room temperature for 28 days due to decreasing of the amount of substrate and or stability of proteases. In addition, we found also that the sausage inoculated by L. acidophilus IIA-2B4 tends to produce more aromatic amino acids than that of L. plantarum IIA-2C12. This might differently contribute to flavor (especially aroma of both sausages. Altogether, this is, to our knowledge, first evidences for the proteolytic activity of L. acidophilus strain towards muscle proteins during sausage fermentation.

  12. Tanshinone IIA Inhibits Proliferation and Induces Apoptosis Through the Downregulation of Survivin in Keloid Fibroblasts.

    Science.gov (United States)

    Chen, Gang; Liang, Yimin; Liang, Xiao; Li, Qingfeng; Liu, Dalie

    2016-02-01

    Keloids are considered benign dermal fibroproliferative tumors. Keloid fibroblasts (KFs) persistently proliferate and fail to undergo apoptosis, and no treatment is completely effective against these lesions. Tanshinone IIA induces apoptosis and inhibits the proliferation of various tumor cell types. In this study, we investigated the effect of tanshinone IIA on the regulation of proliferation, cell cycle, and apoptosis in KFs, and investigated potential mechanisms involved in the effects. First, KFs and normal skin fibroblasts (NSFs) were treated with various concentrations of tanshinone IIA. Cell counting kit-8 (CCK-8) was used to assess the proliferative activity of KFs and NSFs, and flow cytometry was used to investigate the cell cycle and apoptosis in KFs. We found that the proliferation of all tanshinone IIA-treated KFs was significantly decreased after treatment for 72 hours (P < 0.001). Also, NSFs treated with tanshinone IIA did not exhibit noticeable effects compared with KFs. In addition, the percentages of G0/G1 cells in all tanshinone IIA-treated KFs were significantly increased after treatment for 72 hours (P < 0.001). And the percentages of cells undergoing early apoptosis in all tanshinone IIA-treated KFs were significantly increased after treatment for 120 hours (P < 0.001). Furthermore, the apoptosis antibody array kit and Western blot analysis revealed that tanshinone IIA decreased survivin expression in KFs (P < 0.001). In conclusion, tanshinone IIA downregulates survivin and deactivates KFs, thus suggesting that tanshinone IIA could serve as a potential clinical keloid treatment. PMID:26101974

  13. PRELIMINARY DETECTION OF BACTERIOCIN-LIKE INHIBITORY SUBSTANCES PRODUCED BY ENTEROCOCCUS SPECIESISOLATED FROM DIFFERENT SOURCES

    Directory of Open Access Journals (Sweden)

    Snehal P Nemade and M Musaddiq

    2012-06-01

    Full Text Available Some lactic acid bacteria and particularly species belonging to the genus Enetrococcus are known to produce bacteriocin like inhibitory substance (BLIS. Usually they are small cationic peptide with bactericidal activity. The antimicrobial peptide produced by bacteria that deserve considerable interest for their use as natural and non-toxic food preservatives. The use of bacteriocin is among the new approaches as it has major potential in preservatives. Broad spectrum activities against prominent pathogens make it an issue of medical interest. The ability to produce such a biocompound may play role in providing an ecological advantage on non-bacteriocin producer species. 34 strains of Enterococci were isolated from different sources. These strains were identified to species: E. faecalis and E. faecium. Direct antimicrobial activity against indicator strain S. aureus was detected in 34 of the tested isolates. From these, only 7 displayed strong inhibitory activity against this indicator strain. The antimicrobial activity was altered after treatment with trypsin, α-chymotrypsin, papain which confirms the proteinaceous nature of the inhibition. This fact suggests that bacteriocin-like substance produced by Enterococcus strains may find application as biopreservatives in food products. Hence, the focus here is put on bacteriocin like substance screened by Enterococcus species isolated from different sources

  14. Activity of bacteriocins synthesized by Bacillus thuringiensis against Staphylococcus aureus isolates associated to bovine mastitis.

    Science.gov (United States)

    Barboza-Corona, José Eleazar; de la Fuente-Salcido, Norma; Alva-Murillo, Nayeli; Ochoa-Zarzosa, Alejandra; López-Meza, Joel E

    2009-07-01

    Antimicrobial therapy is a useful tool to control bovine mastitis caused by Staphylococcus aureus, as consequence an increase in staphylococci resistant cases has been registered. Alternative strategies are desirable and bacteriocins represent attractive control agents to prevent bovine mastitis. The aim of this work was to evaluate the activity of five bacteriocins synthesized by Bacillus thuringiensis against S. aureus isolates associated to bovine mastitis. Fifty S. aureus isolates were recovered from milk composite samples of 26 Holstein lactating cows from one herd during September 2007 to February 2008 in México and susceptibility of those isolates to 12 antibiotics and 5 bacteriocins from B. thuringiensis was evaluated. S. aureus isolates were mainly resistant to penicillin (92%), dicloxacillin (86%), ampicillin (74%) and erythromycin (74%); whereas susceptibility to gentamicin, trimethoprim and tetracycline was detected at, respectively, 92%, 88%, and 72%. All S. aureus isolates showed susceptibility to the five bacteriocins synthesized by B. thuringiensis, mainly to morricin 269 and kurstacin 287 followed by kenyacin 404, entomocin 420 and tolworthcin 524. Our results showed that S. aureus isolates had differences in the antimicrobial resistance patterns and were susceptible to bacteriocins produced by B. thuringiensis, which could be useful as an alternative method to control bovine mastitis. PMID:19359107

  15. Purification and Characterization of Bacteriocin Produced by Weissella confusa A3 of Dairy Origin.

    Directory of Open Access Journals (Sweden)

    Hweh Fen Goh

    Full Text Available A dramatic increase in bacterial resistance towards currently available antibiotics has raised worldwide concerns for public health. Therefore, antimicrobial peptides (AMPs have emerged as a promisingly new group of therapeutic agents for managing infectious diseases. The present investigation focusses on the isolation and purification of a novel bacteriocin from an indigenous sample of cow milk and it's mode of action. The bacteriocin was isolated from Weissella confusa A3 that was isolated from the sample and was shown to have inhibitory activity towards pathogenic bacteria namely Bacillus cereus, Escherichia coli, Pseudomonas aeruginosa and Micrococcus luteus. The bacteriocin was shown to be heat stable and functioned well at low pH (2 to 6. Reduction of activity was shown after treatment with proteinase K, trypsin and peptidase that confirmed the proteinaceous nature of the compound. MALDI-TOF analysis of the sample gave a mass approximating 2.7 kDa. The membrane of the bacteria was disrupted by the bacteriocin causing SYTOX® green dye to enter the cell and bind to the bacterial DNA giving fluorescence signal. Bacterial cell treated with the bacteriocin also showed significant morphological changes under transmission electron microscope. No virulence and disease related genes can be detected from the genome of the strain.

  16. Partial purification and characterization of a bacteriocin produced by Enterococcus faecium 130 isolated from mozzarella cheese

    Directory of Open Access Journals (Sweden)

    Fabrício Luiz Tulini

    2011-03-01

    Full Text Available Lactic acid bacteria are important in foods as potential probiotics and also due to the ability to produce antimicrobial compounds that can contribute for biopreservation. In this work, the bacteriocin produced by the food isolate Enterococcus faecium 130 was partially purified and characterized. The compound was active against Gram-positive bacteria, including Listeria monocytogenes. It was produced after 4 days of storage at a broad temperature range (4 to 37 °C; it was stable at pH ranging from 2 to 10 with no loss of activity after heating at 100 °C for 15 minutes. Bacteriocin was partially purified by the adsorption-desorption technique, and the analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE showed a molecular mass of 3.5 to 6.5 kDa. These data encourage studies on application of this bacteriocin in food systems as an additional hurdle to microbial growth.

  17. Analysis of natural isolates of Lactobacilli resistant to bacteriocin nisin

    Directory of Open Access Journals (Sweden)

    Strahinić Ivana D.

    2005-01-01

    Full Text Available The collection of lactic acid bacteria (LAB was made by isolation of microorganisms from fermented products traditionally manufactured in different geographical regions (high mountains, river valleys, seaside, etc. Among collected LAB, 51 isolates were identified as Lactobacillus sp. Results showed that all isolated lactobacilli were mesophilic strains, since they grew at 15°C and 30°C but not at 45°C. Testing the ability of isolated lactobacilli to grow in the presence of nisin revealed that Lactobacillus sp. isolates designed BGCGK4, BGHN40, BGBUK2-8, BGBUK2-7 and BGBUK2-16 were resistant to nisin. Determination of the minimal inhibitory concentrations (MIC for nisin revealed that the most resistant isolate was Lactobacillus sp. BGCGK4. Isolate BGBUK2-16, determined as Lactobacillus paracasei subsp. paracasei, produces bacteriocin, named Bac217 and showed a resistance to 8000 IU/ml of nisin. Plasmid curing of BGBUK2-16 resulted in derivatives BGBUK2-16/K2 and BGBUK2-16/K4. Derivative BGBUK2-16/K2 retained resistance to Bac217 and nisin, but lost the ability to synthesise Bac217. Derivative BGBUK2-16/K4 lost concomitantly the resistance to both Bac217 and nisin.

  18. Coculture-inducible bacteriocin biosynthesis of different probiotic strains by dairy starter culture Lactococcus lactis

    Directory of Open Access Journals (Sweden)

    Blaženka Kos

    2011-12-01

    Full Text Available Bacteriocins produced by probiotic strains effectively contribute to colonization ability of probiotic strains and facilitate their establishment in the competitive gut environment and also protect the gut from gastrointestinal pathogens. Moreover, bacteriocins have received considerable attention due to their potential application as biopreservatives, especially in dairy industry. Hence, the objective of this research was to investigate antimicrobial activity of probiotic strains Lactobacillus helveticus M92, Lactobacillus plantarum L4 and Enterococcus faecium L3, with special focus on their bacteriocinogenic activity directed towards representatives of the same or related bacterial species, and towards distant microorganisms including potential food contaminants or causative agents of gut infections. In order to induce bacteriocin production, probiotic cells were cocultivated with Lactococcus lactis subsp. lactis LMG 9450, one of the most important starter cultures in cheese production. The presence of bacteriocin coding genes was investigated by PCR amplification with sequence-specific primers for helveticin and was confirmed for probiotic strain L. helveticus M92. All examined probiotic strains have shown bacteriocinogenic activity against Staphylococcus aureus 3048, Staphylococcus aureus K-144, Escherichia coli 3014, Salmonella enterica serovar Typhimurium FP1, Bacillus subtilis ATCC 6633, Bacillus cereus TM2, which is an important functional treat of probiotic strains significant in competitive exclusion mechanism which provides selective advantage of probiotic strains against undesirable microorganisms in gastrointestinal tract of the host. According to obtained results, living cells of starter culture Lc. lactis subsp. lactis LMG 9450 induced bacteriocin production by examined probiotic strains but starter culture itself was not sensitive to bacteriocin activity.

  19. Bacteriocins from lactic acid bacteria: purification, properties and use as biopreservatives

    Directory of Open Access Journals (Sweden)

    José Luis Parada

    2007-05-01

    Full Text Available Biopreservation systems in foods are of increasing interest for industry and consumers. Bacteriocinogenic lactic acid bacteria and/or their isolated bacteriocins are considered safe additives (GRAS, useful to control the frequent development of pathogens and spoiling microorganisms in foods and feed. The spreading of bacterial antibiotic resistance and the demand for products with fewer chemicals create the necessity of exploring new alternatives, in order to reduce the abusive use of therapeutic antibiotics. In this context, bacteriocins are indicated to prevent the growth of undesirable bacteria in a food-grade and more natural way, which is convenient for health and accepted by the community. According to their properties, structure, molecular weight (MW, and antimicrobial spectrum, bacteriocins are classified in three different groups: lantibiotics and non-lantibiotics of low MW, and those of higher MW. Several strategies for isolation and purification of bacteriocins from complex cultivation broths to final products were described. Biotechnological procedures including salting-out, solvent extraction, ultrafiltration, adsorption-desortion, ion-exchange, and size exclusion chromatography are among the most usual methods. Peptide structure-function studies of bacteriocins and bacterial genetic advances will help to understand the molecular basis of their specificity and mode of action. Nisin is a good example of commercial success, and a good perspective is open to continue the study and development of new bacteriocins and their biotechnological applications. These substances in appropriate concentrations may be used in veterinary medicine and as animal growth promoter instead usual antibiotics, as well as an additional hurdle factor for increasing the shelf life of minimal processed foods.

  20. Optimization of growth and bacteriocin production by Lactobacillus sakei subsp. sakei2a

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    Patrícia S. Malheiros

    2015-09-01

    Full Text Available Lactobacillus sakei subsp. sakei 2a is a bacteriocinogenic lactic acid bacterium isolated from Brazilian pork sausage, capable of inhibiting the growth of microbial pathogens, mainly Listeria monocytogenes. In order to optimize bacteriocin production for industrial applications, this study evaluated the effect of supplementation of MRS broth with glucose, Tween 20, Tween 80, sodium citrate, potassium chloride and cysteine, and effect of the initial pH and temperature of incubation of the medium on production of bacteriocins by L. sakei 2a. Adding glucose and Tween 20 to the medium, an initial pH of 5.0 or 5.5, and incubation temperatures of 25 °C or 30 °C resulted to the highest bacteriocin yields. Thus, a 24 factorial design with the four variables was performed, and statistical analysis showed that it was an adequate model (R2 = 0.8296. In the studied range, the four parameters significantly influenced bacteriocin production, with the maximum yield produced at an initial pH between 5.5 and 7.0, a temperature between 25 and 30 °C and supplementation of the MRS broth with glucose from 3.25 to 6.0 g L−1 and Tween 20 from 0.575 to 1.15% (v/v. Response Surface Methodology analysis indicated that the highest bacteriocin production (12800 AU mL−1 occurred in the MRS broth supplemented with 5.5 g L−1 glucose and 1.05% Tween 20 at an initial pH of 6.28 and an incubation temperature of 25 °C. The amount of bacteriocin produced in commercial MRS broths under the same conditions was only 5600AU mL−1.

  1. Inhibition of propionibacterium acnes by bacteriocin-like inhibitory substances (BLIS) produced by Streptococcus salivarius.

    Science.gov (United States)

    Bowe, Whitney P; Filip, Jennifer C; DiRienzo, Joseph M; Volgina, Alla; Margolis, David J

    2006-10-01

    We report the in vitro inhibition of Propionibacterium acnes (P. acnes) by a bacteriocin-like inhibitory substance (BLIS-like substance) produced by Streptococcus salivarius (S. salivarius). Bacteriocins are proteinaceous substances produced by bacteria that are capable of inhibiting the growth of similar bacterial strains. Unlike classical antibiotics, they have a relatively narrow spectrum of killing activity, resulting in a reduction in the intensity of selection for resistance. These findings suggest that BLIS may potentially be used for its anti-P. acnes activity in the treatment of acne. PMID:17039652

  2. Production of Antilisterial Bacteriocins from Lactic Acid Bacteria in Dairy-Based Media: A Comparative Study.

    Science.gov (United States)

    Ünlü, Gülhan; Nielsen, Barbara; Ionita, Claudia

    2015-12-01

    One hundred and eight strains of lactic acid bacteria (LAB) were screened for bacteriocin production by the modified deferred antagonism and agar well diffusion methods. When the modified deferred antagonism method was employed, 82 LAB strains showed inhibitory action against Listeria monocytogenes v7 ½a, whereas 26 LAB strains expressed no inhibition. Only 12 LAB strains exhibited inhibitory activity when the agar well diffusion method was used, 11 of which had been previously recognized as bacteriocin production positive (Bac(+)). Lactobacillus viridescens NRRL B-1951 was determined, for the first time, to produce an inhibitory compound with a proteinaceous nature. The inhibitory activity was observed in the presence of lipase, α-chymotrypsin, and trypsin, but no inhibition zone could be detected in the presence of proteinase K, indicating the proteinaceous nature of the inhibitory compound. The inhibitory compound was active against Lact. sake ATCC 15521 and Lact. plantarum NCDO 995. Bacteriocin production by the Bac(+) LAB strains was assessed in Lactobacillus MRS Broth as well as in dairy-based media such as nonfat milk, demineralized whey powder, and cheddar cheese whey supplemented with complex nutrient sources that are rich in nitrogen. Lact. sake ATCC 15521 and L. monocytogenes CWD 1002, CWD 1092, CWD 1157, CWD 1198, and v7 ½a were used as indicators. The inhibitory activities of the bacteriocins varied depending on the indicator strains and the growth media used. The LAB indicator strains were found to be more sensitive to inhibition by bacteriocins when compared to the listerial indicator strains. Among the listerial indicators, L. monocytogenes CWD 1002 and CWD 1198 were the most sensitive strains to the bacteriocins investigated in this study. Media composition had a significant influence on bacteriocin production and activity. When compared to demineralized whey powder medium and cheddar cheese whey medium supplemented with whey protein concentrate

  3. Fixing moduli in exact type IIA flux vacua

    International Nuclear Information System (INIS)

    Type IIA flux compactifications with O6-planes have been argued from a four dimensional effective theory point of view to admit stable, moduli free solutions. We discuss in detail the ten dimensional description of such vacua and present exact solutions in the case when the O6-charge is smoothly distributed. In the localised case, the solution is a half-flat, non-Calabi-Yau metric. Finally, using the ten dimensional description we show how all moduli are stabilised and reproduce precisely the results of de Wolfe et al. (author)

  4. Atlas II and IIA analyses and environments validation

    Science.gov (United States)

    Martin, Richard E.

    1995-06-01

    General Dynamics has now flown all four versions of the Atlas commercial launch vehicle, which cover a payload weight capability to geosynchronous transfer orbit (GTO) in the range of 5000-8000 lb. The key analyses to set design and environmental test parameters for the vehicle modifications and the ground and flight test data that validated them were prepared in paper IAF-91-170 for the first version, Atlas I. This paper presents similar data for the next two versions, Atlas II and IIA. The Atlas II has propellant tanks lengthened by 12 ft and is boosted by MA-5A rocket engines uprated to 474,000 lb liftoff thrust. GTO payload capability is 6225 lb with the 11-ft fairing. The Atlas IIA is an Atlas II with uprated RL10A-4 engines on the lengthened Centaur II upper stage. The two 20,800 lb thrust, 449 s specific impulse engines with an optional extendible nozzle increase payload capability to GTO to 6635 lb. The paper describes design parameters and validated test results for many other improvements that have generally provided greater capability at less cost, weight and complexity and better reliability. Those described include: moving the MA-5A start system to the ground, replacing the vernier engines with a simple 50 lb thrust on-off hydrazine roll control system, addition of a POGO suppressor, replacement of Centaur jettisonable insulation panels with fixed foam, a new inertial navigation unit (INU) that combines in one package a ring-laser gyro based strapdown guidance system with two MIL-STD-1750A processors, redundant MIL-STD-1553 data bus interfaces, robust Ada-based software and a new Al-Li payload adapter. Payload environment is shown to be essentially unchanged from previous Atlas vehicles. Validation of load, stability, control and pressurization requirements for the larger vehicle is discussed. All flights to date (five Atlas II, one Atlas IIA) have been successful in launching satellites for EUTELSAT, the U.S. Air Force and INTELSAT. Significant design

  5. ANTIMICROBIAL ACTIVITY OF BACTERIOCIN FROM INDIGENOUS Lactobacillus plantarum 2C12 AND ITS APPLICATION ON BEEF MEATBALL AS BIOPRESERVATIVE

    Directory of Open Access Journals (Sweden)

    T. Suryati

    2012-06-01

    Full Text Available One purpose of food preservation is to extend the shelf life of foods. Biological preservations can be conducted by adding antimicrobial substances, such as bacteriocin produced by lactic acid bacteria and has been characterized as biopreservatives. The aims of this research were to evaluate antimicrobial activity of bacteriocin produced by indigenous lactic acid bacteria Lactobacillus plantarum 2C12 isolated from local beef and to study the quality of beef meatball with 0.3% bacteriocin as biopreservative at different storage times (0, 3, and 6 days in cold temperature (4oC, compared to 0.3% nitrite and control (without preservative. The results showed that bacteriocin from L. plantarum 2C12 could inhibit pathogenic bacteria such as Escherichia coli, Staphylococcus aureus and Salmonella Typhimurium. Bacteriocin was effective as well as nitrite as biopreservatives of meatballs by inhibiting the growth of total microbes and E. coli. The addition of bacteriocin did not lead the physical and nutritional changes in the meatballs. The quality of meatball with bacteriocin treatment conformed with Indonesia National Standard of meatball.

  6. Two-Component Regulatory Systems – implication in the quorum sensing mechanisms and bacteriocin production in lactic acid bacteria

    Directory of Open Access Journals (Sweden)

    Lia–Mara Ditu

    2014-08-01

    Full Text Available For lactic acid bacteria, the mechanisms of quorum sensing and response are mediated by peptides or pheromones that interfere with the synthesis of antimicrobial peptides (AMP called bacteriocins, when these molecules reach a certain critical level of concentration. Generally, the synthesis and activity of pheromones is adjusted by means of a two-component regulatory system. The observation that some microorganisms, in particular lactic acid bacteria, produce bacteriocins according to the cell density, has led to the discovery of the involvement of QS mechanisms in the synthesis of these peptides. Bacteriocins synthesis is inducible, the process requiring the extracellular accumulation of peptides that functions as chemical messengers activators of bacteriocins synthesis. This minireview presents the molecular architecture and functions of two-component regulatory systems and ABC transporters implicated in the synthesis and secretion of nisin, one of the most studied bacteriocin. The elucidation of the intimate mechanisms of bacteriocins synthesis is equally of biotechnological and medical importance, opening interesting perspectives for the development of improved technologies for the production of bacteriocins with good yields, and also, for increasing the beneficial anti-infective roles of probiotic bacteria when administered in vivo.

  7. Cloning and Genetic Analyses of the Bacteriocin 41 Determinant Encoded on the Enterococcus faecalis Pheromone-Responsive Conjugative Plasmid pYI14: a Novel Bacteriocin Complemented by Two Extracellular Components (Lysin and Activator)▿ †

    OpenAIRE

    Tomita, Haruyoshi; Kamei, Elizabeth; Ike, Yasuyoshi

    2008-01-01

    The conjugative plasmid pYI14 (61 kbp) was isolated from Enterococcus faecalis YI714, a clinical isolate. pYI14 conferred a pheromone response on its host and encoded bacteriocin 41 (bac41). Bacteriocin 41 (Bac41) only showed activity against E. faecalis. Physical mapping of pYI14 showed that it consisted of EcoRI fragments A to P. The clone pHT1100, containing EcoRI fragments A (12.6 kbp) and H (3.5 kbp), conferred the bacteriocin activity on E. faecalis strains. Genetic analysis showed that...

  8. Holographic compactifications of (1,0) theories from massive IIA supergravity

    CERN Document Server

    Apruzzi, Fabio; Passias, Achilleas; Rota, Andrea; Tomasiello, Alessandro

    2015-01-01

    We describe three analytic classes of infinitely many AdS_d BPS solutions of massive IIA supergravity, for d = 7, 5, 4. The three classes are related by simple universal maps. For example, the AdS_7 x M_3 solutions (where M_3 is topologically S^3) are mapped to AdS_5 x Sigma_2 x M'_3, where Sigma_2 is a Riemann surface of genus g >= 2 and the metric on M'_3 is obtained by distorting M_3 in a certain way. The solutions can have localized D6 or O6 sources, as well as an arbitrary number of D8-branes. The AdS_7 case (previously known only numerically) is conjecturally dual to an NS5-D6-D8 system. The field theories in three and four dimensions are not known, but their number of degrees of freedom can be computed at leading order. The AdS_4 solutions have numerical "attractor" generalizations that might be useful for flux compactification purposes.

  9. Six-Dimensional Superconformal Theories and their Compactifications from Type IIA Supergravity

    Science.gov (United States)

    Apruzzi, Fabio; Fazzi, Marco; Passias, Achilleas; Rota, Andrea; Tomasiello, Alessandro

    2015-08-01

    We describe three analytic classes of infinitely many AdSd supersymmetric solutions of massive IIA supergravity, for d =7 ,5 ,4 . The three classes are related by simple universal maps. For example, the AdS7×M3 solutions (where M3 is topologically S3 ) are mapped to AdS5×Σ2×M3' , where Σ2 is a Riemann surface of genus g ≥2 and the metric on M3' is obtained by distorting M3 in a certain way. The solutions can have localized D6 or O6 sources, as well as an arbitrary number of D8-branes. The AdS7 case (previously known only numerically) is conjecturally dual to an NS5-D6-D8 system. The field theories in three and four dimensions are not known, but their number of degrees of freedom can be computed in the supergravity approximation. The AdS4 solutions have numerical "attractor" generalizations that might be useful for flux compactification purposes.

  10. 30 CFR 57.22307 - Methane monitors (II-A mines).

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Methane monitors (II-A mines). 57.22307 Section... Standards for Methane in Metal and Nonmetal Mines Equipment § 57.22307 Methane monitors (II-A mines). (a) Methane monitors shall be installed on continuous mining machines, longwall mining systems, bench and...

  11. Explore the Molecular Mechanism of Apoptosis Induced by Tanshinone IIA on Activated Rat Hepatic Stellate Cells

    Directory of Open Access Journals (Sweden)

    Tai-Long Pan

    2012-01-01

    Full Text Available Since the activated hepatic stellate cell (HSC is the predominant event in the progression of liver fibrosis, selective clearance of HSC should be a potential strategy in therapy. Salvia miltiorrhiza roots ethanol extract (SMEE remarkably ameliorates liver fibrogenesis in DMN-administrated rat model. Next, tanshinone IIA (Tan IIA, the major compound of SMEE, significantly inhibited rat HSC viability and led to cell apoptosis. Proteome tools elucidated that increased prohibitin is involved in cell cycle arrest under Tan IIA is the treatment while knockdown of prohibitin could attenuate Tan IIA-induced apoptosis. In addition, Tan IIA mediated translocation of C-Raf which interacted with prohibitin activating MAPK and inhibiting AKT signaling in HSC. MAPK antagonist suppressed ERK phosphorylation which was necessary for Tan IIA-induced expression of Bax and cytochrome c. PD98059 also abolished Tan IIA-modulated cleavage of PARP. Our findings suggested that Tan IIA could contribute to apoptosis of HSC by promoting ERK-Bax-caspase pathways through C-Raf/prohibitin complex.

  12. Anti-Inflammatory and Immunomodulatory Mechanism of Tanshinone IIA for Atherosclerosis

    Directory of Open Access Journals (Sweden)

    Zhuo Chen

    2014-01-01

    Full Text Available Tanshinone IIA (Tan II A is widely used in the treatment of cardiovascular diseases as an active component of Salvia miltiorrhiza Bunge. It has been demonstrated to have pleiotropic effects for atherosclerosis. From the anti-inflammatory and immunomodulatory mechanism perspective, this paper reviewed major progresses of Tan IIA in antiatherosclerosis research, including immune cells, antigens, cytokines, and cell signaling pathways.

  13. Bacteriocin formation by dominant aerobic sporeformers isolated from traditional maari

    DEFF Research Database (Denmark)

    Kaboré, Donatien; Thorsen, Line; Nielsen, Dennis Sandris;

    2012-01-01

    antimicrobial substances produced were heat stable, in-sensitive to catalase, sensitive to protease and trypsin but resistant to the proteolytic action of papain and proteinase K and equally active at pH values ranging from 3 to 11. Bacteriocin secretion started in late exponential growth phase and maximum...

  14. Genetic features of circular bacteriocins produced by Gram-positive bacteria

    NARCIS (Netherlands)

    Maqueda, Mercedes; Sánchez-Hidalgo, Marina; Fernández, Matilde; Montalbán-López, Manuel; Valdivia, Eva; Martínez-Bueno, Manuel

    2008-01-01

    This review highlights the main genetic features of circular bacteriocins, which require the co-ordinated expression of several genetic determinants. In general terms, it has been demonstrated that the expression of such structural genes must be combined with the activity of proteins involved in mat

  15. Lactococcin G Is a Potassium Ion-Conducting, Two-Component Bacteriocin

    NARCIS (Netherlands)

    Moll, Gert; Ubbink-Kok, Trees; Hildeng-Hauge, Håvard; Nissen-Meyer, Jon; Nes, Ingolf F.; Konings, Wil N.; Driessen, Arnold J.M.

    1996-01-01

    Lactococcin G is a novel lactococcal bacteriocin whose activity depends on the complementary action of two peptides, termed α and β. Peptide synthesis of the α and β peptides yielded biologically active lactococcin G, which was used in mode-of-action studies on sensitive cells of Lactococcus lactis.

  16. Cysteine S-glycosylation, a new post-translational modification found in glycopeptide bacteriocins

    Czech Academy of Sciences Publication Activity Database

    Stepper, J.; Shastri, S.; Loo, T. S.; Preston, J. C.; Novák, Petr; Man, Petr; Moore, Ch. H.; Havlíček, Vladimír; Patchett, M. L.; Norris, G. E.

    2011-01-01

    Roč. 585, č. 4 (2011), s. 645-650. ISSN 0014-5793 Institutional research plan: CEZ:AV0Z50200510 Keywords : Post-translational modification * Glycosylation * Bacteriocin Subject RIV: CE - Biochemistry Impact factor: 3.538, year: 2011

  17. Coordinated Bacteriocin Expression and Competence in Streptococcus pneumoniae Contributes to Genetic Adaptation through Neighbor Predation.

    Directory of Open Access Journals (Sweden)

    Wei-Yun Wholey

    2016-02-01

    Full Text Available Streptococcus pneumoniae (pneumococcus has remained a persistent cause of invasive and mucosal disease in humans despite the widespread use of antibiotics and vaccines. The resilience of this organism is due to its capacity for adaptation through the uptake and incorporation of new genetic material from the surrounding microbial community. DNA uptake and recombination is controlled by a tightly regulated quorum sensing system that is triggered by the extracellular accumulation of competence stimulating peptide (CSP. In this study, we demonstrate that CSP can stimulate the production of a diverse array of blp bacteriocins. This cross stimulation occurs through increased production and secretion of the bacteriocin pheromone, BlpC, and requires a functional competence regulatory system. We show that a highly conserved motif in the promoter of the operon encoding BlpC and its transporter mediates the upregulation by CSP. The accumulation of BlpC following CSP stimulation results in augmented activation of the entire blp locus. Using biofilm-grown organisms as a model for competition and genetic exchange on the mucosal surface, we demonstrate that DNA exchange is enhanced by bacteriocin secretion suggesting that co-stimulation of bacteriocins with competence provides an adaptive advantage. The blp and com regulatory pathways are believed to have diverged and specialized in a remote ancestor of pneumococcus. Despite this, the two systems have maintained a regulatory connection that promotes competition and adaptation by targeting for lysis a wide array of potential competitors while simultaneously providing the means for incorporation of their DNA.

  18. Relationships between MDR proteins, bacteriocin production and proteolysis in Lactococcus lactis

    NARCIS (Netherlands)

    Gajic, Olivera

    2003-01-01

    The Gram-positive lactic acid bacterium Lactococcus lactis can harbour a wide variety of circular extrachromosomal DNA molecules, so-called plasmids. Many of the traits that make them useful for manufacturing of fermented food products (e.g. bacteriophage resistance, bacteriocin and proteinase produ

  19. BlpC regulated bacteriocin production in Streptococcus thermophilus NRRL-B59671

    Science.gov (United States)

    Streptococcus thermophilus NRRL-B59671 was previously shown to produce a bacteriocin with anti-pediococcal activity, but the genetic components required for production were not characterized. Genome sequencing of several strains of S. thermophilus has identified a genetic locus which encodes a quor...

  20. Molecular characterization of MHC class II in the Australian invasive cane toad reveals multiple splice variants.

    Science.gov (United States)

    Lillie, Mette; Cui, Jian; Shine, Richard; Belov, Katherine

    2016-07-01

    The cane toad has gained notoriety for its invasion across the Australian landscape, with significant impacts on the native Australian fauna. The invasion has accelerated over time, with invading cane toads adapted for highly dispersive traits. This, however, has come at the cost of the immune system, with lower investment in some immune functions. To investigate the cane toad's immunogenetics, we characterized four major histocompatibility complex (MHC) class IIA and three MHC class IIB loci. Preliminary observations suggest very low allelic diversity at all loci. We also observed various splice isoforms. One isoform seen at one class IIA and two class IIB loci was missing exon 2, which is essential to peptide binding and presentation. The other isoform, observed at a class IIA locus, is likely to be a soluble MHC product. These results may suggest a significant role of alternative splicing of MHC loci in the Australian cane toad. PMID:27233954

  1. Purification and biochemical characterization of a secreted group IIA chicken intestinal phospholipase A2

    Directory of Open Access Journals (Sweden)

    Gargouri Youssef

    2011-02-01

    Full Text Available Abstract Background Secretory phospholipase A2 group IIA (IIA PLA2 is a protein shown to be highly expressed in the intestine of mammals. However, no study was reported in birds. Results Chicken intestinal group IIA phospholipase A2 (ChPLA2-IIA was obtained after an acidic treatment (pH.3.0, precipitation by ammonium sulphate, followed by sequential column chromatographies on Sephadex G-50 and mono-S ion exchanger. The enzyme was found to be a monomeric protein with a molecular mass of around 14 kDa. The purified enzyme showed a substrate preference for phosphatidylethanolamine and phosphatidylglycerol, and didn't hydrolyse phosphatidylcholine. Under optimal assay conditions, in the presence of 10 mM NaTDC and 10 mM CaCl2, a specific activity of 160 U.mg-1 for purified ChPLA2-IIA was measured using egg yolk as substrate. The fifteen NH2-terminal amino acid residues of ChPLA2-IIA were sequenced and showed a close homology with known intestinal secreted phospholipases A2. The gene encoding the mature ChPLA2-IIA was cloned and sequenced. To further investigate structure-activity relationship, a 3D model of ChPLA2-IIA was built using the human intestinal phospholipase A2 structure as template. Conclusion ChPLA2-IIA was purified to homogeneity using only two chromatographic colomns. Sequence analysis of the cloned cDNA indicates that the enzyme is highly basic with a pI of 9.0 and has a high degree of homology with mammalian intestinal PLA2-IIA.

  2. Effect of bacteriocin from Lactobacillus sp. Var. SCG 1223 on microbiological quality of fresh meat

    Directory of Open Access Journals (Sweden)

    Sri Usmiati

    2009-06-01

    Full Text Available Inhibition technology of microorganism on meat can be done biologically and chemically. Biologically, inhibition to microbe can be conducted by addition antimicrobe, for example bacteriocin that have character as biopreservative. The aim of this research was to study the microbiological quality of fresh meat with bacteriocin isolated from Lactobacillus sp. SCG 1223 storaged at certain addition and temperature with different storage time. This experiment was done based on Completely of Random Design (CRD with factorial arragement 3 x 4 for meat kept at room temperature (270C and 3x3 for meat kept at cold temperature (4ºC in three replications. The first factor was addition of biopreservative: addition bacteriocin (B, without addition antimicrobia (TB, and addition of nisin (N on fresh meat. The second factor was different storage time at room temperature (H0, H6, H12 and H18 and low temperature (D0, D14, D28. Other treatments as indicators was contaminated with indicator bacteria (S. thypimurium, E. coli, L. monocytogenes. Variable analyzed were initial TPC (Total Plate Count and total indicator bacteria S. thypimurium; E. coli; L. monocytogenes at fresh meat, meat quality consist of total indicator of bacteria, pH value of meat; and protein level. Result indicated that bacteriocin from Lactobacillus sp. SCG 1223 isolat could inhibit bacteria growth (S. thypimurium, L. monocytogenes, and E. coli. Bacteriocin produced by Lactobacillus sp. can work at room temperature (270C and cold temperature (40C. Nisin effectivity almost same to bacteriosin produced from Lactobacillus sp. SCG 1223 isolated from cow fresh milk in inhibiting Gram positive L. monocytogenes.

  3. Variable characteristics of bacteriocin-producing Streptococcus salivarius strains isolated from Malaysian subjects.

    Directory of Open Access Journals (Sweden)

    Abdelahhad Barbour

    Full Text Available BACKGROUND: Salivaricins are bacteriocins produced by Streptococcus salivarius, some strains of which can have significant probiotic effects. S. salivarius strains were isolated from Malaysian subjects showing variable antimicrobial activity, metabolic profile, antibiotic susceptibility and lantibiotic production. METHODOLOGY/PRINCIPAL FINDINGS: In this study we report new S. salivarius strains isolated from Malaysian subjects with potential as probiotics. Safety assessment of these strains included their antibiotic susceptibility and metabolic profiles. Genome sequencing using Illumina's MiSeq system was performed for both strains NU10 and YU10 and demonstrating the absence of any known streptococcal virulence determinants indicating that these strains are safe for subsequent use as probiotics. Strain NU10 was found to harbour genes encoding salivaricins A and 9 while strain YU10 was shown to harbour genes encoding salivaricins A3, G32, streptin and slnA1 lantibiotic-like protein. Strain GT2 was shown to harbour genes encoding a large non-lantibiotic bacteriocin (salivaricin-MPS. A new medium for maximum biomass production buffered with 2-(N-morpholinoethanesulfonic acid (MES was developed and showed better biomass accumulation compared with other commercial media. Furthermore, we extracted and purified salivaricin 9 (by strain NU10 and salivaricin G32 (by strain YU10 from S. salivarius cells grown aerobically in this medium. In addition to bacteriocin production, S. salivarius strains produced levan-sucrase which was detected by a specific ESI-LC-MS/MS method which indicates additional health benefits from the developed strains. CONCLUSION: The current study established the bacteriocin, levan-sucrase production and basic safety features of S. salivarius strains isolated from healthy Malaysian subjects demonstrating their potential for use as probiotics. A new bacteriocin-production medium was developed with potential scale up application for

  4. Determination of antibiotic resistance pattern and bacteriocin sensitivity of Listeria monocytogenes strains isolated from different foods in turkey

    Science.gov (United States)

    This study aimed to determine the antibiotic resistance pattern and bacteriocin sensitivity of Listeria monocytogenes strains isolated from animal derived foods. With disc diffusion assay, all fourteen L. monocytogenes strains were susceptible to the antibiotics, including penicillin G, vancomycin, ...

  5. Variacin, a new lanthionine-containing bacteriocin produced by Micrococcus varians: comparison to lacticin 481 of Lactococcus lactis.

    OpenAIRE

    Pridmore, D; Rekhif, N; Pittet, A C; Suri, B.; Mollet, B

    1996-01-01

    A new lanthionine-containing bacteriocin, variacin, displaying a broad host range of inhibition against gram-positive food spoilage bacteria, has been identified from two strains of Micrococcus varians isolated from meat fermentations. The new bacteriocin was purified, and its amino-terminal end and total amino acid composition were determined. The structural gene was isolated and analyzed. Variacin is resistant to heat and pH conditions from 2 to 10. Its primary sequence shows significant ho...

  6. EFFECT OF CULTURE MEDIUM ON BACTERIOCIN PRODUCTION BY LACTOBACILLUS RHAMNOSUS HN001 AND LACTOBACILLUS REUTERI ATCC 53608

    Directory of Open Access Journals (Sweden)

    Aguilar-Uscanga B. R.

    2013-06-01

    Full Text Available The aim of this study was to evaluate the effect of media on bacteriocin production by Lactobacillus rhamnosus HN001 and Lactobacillus reuteri ATCC 53608 using three different media: YPM, YPF and MRS supplemented with glucose and K2HPO4. The optimum temperature was 37°C and initial pH 6.5. Bacteriocin-like substances produced by tested bacteria in MRS medium supplemented with glucose and K2HPO4 exhibited a broad antimicrobial spectrum determined by well diffusion assay against indicator bacteria Listeria monocytogenes, Lactobacillus sakei, Enterococcus faecium, Lactobacillus delbrueckii, Lactobacillus acidophilus, but no antimicrobial spectrum against E. coli O157:H7, Salmonella typhimurium, Staphylococcus aureus, Bacillus cereus was detected. Bacteriocin was sensitive to protease IV, trypsin, pepsin and -amylases, but resistant to lipase. It was also resistant to detergents such as Tween 80, Triton-X and SDS. This bacteriocin was thermo-stable (resistant at 60°C, 90°C and 100°C for 30 min. Tested bacteria showed the best antimicrobial (bacteriocin-like activity after growth in MRS medium. Bacteriocin substances produced by tested bacteria showed promising thermo-stable technological properties.

  7. Production and characterization of a bacteriocin-like inhibitory substance produced by indigenous soil associated pseudomonas putida mas-1

    International Nuclear Information System (INIS)

    Bacteriocins have been the subject of extensive research globally due to wide range applications. The aim of this research was to investigate the production of bacteriocin(s) or bacteriocin like inhibitory substance(s) by Pseudomonas putida MAS-1 strain. The bacteriocin produced (Putidacin MAS-1) was found bioactive against clinical Staphylococcus aureus and Enterococcus faecalis strains. Bioactivity was observed by stab and overlay assay and multiwell antagonistic activity assay. Putidacin MAS-1 was sensitive beyond 70 degree C but stable at wide pH range (3 to 8). Bioactivity of putidacin MAS-1 was lost after treatment with trypsin and protease while partially lost after Proteinase K treatment. Treatment with ethanol, methanol, chloroform, acetone Tween 20 and Tween 80 showed partial decrease in bioactivity. SDS had stimulatory effect on putidacin MAS-1 bioactivity. EDTA however, showed no effect on the bacteriocin bioactivity. It was partially purified by ammonium sulphate precipitation. SDS-PAGE showed that Putidacin MAS-1 had 15 kDa molecular weight. (author)

  8. Control of Listeria monocytogenes biofilms on industrial surfaces by the bacteriocin-producing Lactobacillus sakei CRL1862.

    Science.gov (United States)

    Pérez-Ibarreche, Mariana; Castellano, Patricia; Leclercq, Alexandre; Vignolo, Graciela

    2016-06-01

    The effect of the bacteriocin-producing Lactobacillus sakei CRL1862 and its bacteriocin in the control of Listeria biofilm formation on industrial surfaces at 10°C was investigated. A screening among different Listeria species was performed allowing selecting L. monocytogenes FBUNT for its use as a biofilm producer on stainless steel (SS) and polytetrafluoroe-thylene (PTFE) surfaces. Three conditions were simulated to evaluate the ability of the bacteriocinogenic strain to displace, exclude and compete pathogen biofilm formation. Lactobacillus sakei CRL1862 effectively inhibited biofilm formation by L. monocytogenes FBUNT through the three assayed mechanisms, pathogen inhibition being more efficient on PTFE than on SS surface. Moreover, co-culture of L. monocytogenes FBUNT with the bacteriocin-producer displayed the highest efficacy reducing the pathogen by 5.54 ± 0.12 and 4.52 ± 0.01 on PTFE and SS, respectively. Industrially, the pre-treatment with L. sakei CRL1862 or its bacteriocin (exclusion) constitutes the most realistic way to prevent pathogen biofilm settlement. The use of bacteriocins and/or the bacteriocin-producer strain represents a safe and environmentally-friendly sanitation method to mitigate post-processing food contamination. PMID:27190146

  9. Antibacterial efficacy of Nisin, Pediocin 34 and Enterocin FH99 against Listeria monocytogenes and cross resistance of its bacteriocin resistant variants to common food preservatives

    OpenAIRE

    Kaur, G; Singh, T.P.; MALIK, R.K.

    2013-01-01

    Antilisterial efficiency of three bacteriocins, viz, Nisin, Pediocin 34 and Enterocin FH99 was tested individually and in combination against Listeria mononcytogenes ATCC 53135. A greater antibacterial effect was observed when the bacteriocins were combined in pairs, indicating that the use of more than one LAB bacteriocin in combination have a higher antibacterial action than when used individually. Variants of Listeria monocytogenes ATCC 53135 resistant to Nisin, Pediocin 34 and Enterocin F...

  10. Value of urinary topoisomerase-IIA cell-free DNA for diagnosis of bladder cancer

    Science.gov (United States)

    Kim, Ye-Hwan; Yan, Chunri; Lee, Il-Seok; Piao, Xuan-Mei; Byun, Young Joon; Jeong, Pildu; Kim, Won Tae; Yun, Seok-Joong

    2016-01-01

    Purpose Topoisomerase-II alpha (TopoIIA ), a DNA gyrase isoform that plays an important role in the cell cycle, is present in normal tissues and various human cancers, and can show altered expression in both. The aim of the current study was to examine the value of urinary TopoIIA cell-free DNA as a noninvasive diagnosis of bladder cancer (BC). Materials and Methods Two patient cohorts were examined. Cohort 1 (73 BC patients and seven controls) provided bladder tissue samples, whereas cohort 2 (83 BC patients, 54 nonmalignant hematuric patients, and 61 normal controls) provided urine samples. Real-time quantitative polymerase chain reaction was used to measure expression of TopoIIA mRNA in tissues and TopoIIA cell-free DNA in urine samples. Results The results showed that expression of TopoIIA mRNA in BC tissues was significantly higher than that in noncancer control tissues (p<0.001). The expression of urinary TopoIIA cell-free DNA in BC patients was also significantly higher than that in noncancer patient controls and hematuria patients (p < 0.001 and p < 0.001, respectively). High expression of urinary TopoIIA cell-free DNA was also detected in muscle invasive bladder cancer (MIBC) when compared with nonmuscle invasive bladder cancer (NMIBC) (p=0.002). Receiver operating characteristics (ROC) curve analysis was performed to examine the sensitivity/specificity of urinary TopoIIA cell-free DNA for diagnosing BC, NMIBC, and MIBC. The areas under the ROC curve for BC, NMIBC, and MIBC were 0.741, 0.701, and 0.838, respectively. Conclusions In summary, the results of this study provide evidence that cell-free TopoIIA DNA may be a potential biomarker for BC. PMID:26981592

  11. Agujeros negros cu\\'anticos en la teor\\'ia de cuerdas tipo-IIA

    CERN Document Server

    Bueno, Pablo

    2013-01-01

    In the context of Type-IIA String Theory compactified to four dimensions on a Calabi-Yau manifold (CY), we study the effect of considering perturbative and non-perturbative corrections (in alpha prime) to the prepotential of the resulting effective Supergravity theory on the space of black hole solutions. Considering the large volume limit of the CY, in which the non-perturbative corrections are exponentially suppressed, we define a new class of solutions which turn out to be genuinely quantum, in the sense that not only their classical limit is not well defined, but also the truncation under consideration becomes inconsistent in such a limit. Next, we construct the first non-extremal black hole solution with non-constant scalars in the presence of perturbative corrections. Right after, restricting ourselves to the case of self-mirror CY, we study the case in which the sub-dominant contribution has a non-perturbative origin, obtaining the first family of explicit supersymmetric solutions of this kind. Surpris...

  12. On the cosmology of type IIA compactifications on SU(3)-structure manifolds

    Science.gov (United States)

    Caviezel, Claudio; Koerber, Paul; Körs, Simon; Lüst, Dieter; Wrase, Timm; Zagermann, Marco

    2009-04-01

    We study cosmological properties of type IIA compactifications on orientifolds of SU(3)-structure manifolds with non-vanishing geometric flux. These compactifications give rise to effective 4D Script N = 1 supergravity theories that do not fall under some recently-proven no-go theorems against de Sitter vacua and slow-roll inflation. Focusing on a well-understood class of models based on coset spaces, however, we can use a refined no-go theorem that rules out de Sitter vacua and slow-roll inflation in all but one case. The refined no-go theorem uses the dilaton and a specific linear combination of the Kähler moduli, which is different from the overall volume modulus. It puts a lower bound on the first slow-roll parameter: epsilon >= 2. The only case not ruled out is the manifold SU(2) × SU(2), for which we indeed find critical points with epsilon numerically zero. However, all the points we could find have a tachyon corresponding to an eta-parameter η lesssim -2.4.

  13. Study on inclusion complexes of hydroxypropyl-β-cyclodextrin with tanshinone IIA

    Institute of Scientific and Technical Information of China (English)

    YAN Jinhong; ZHANG Cuiping; YANG Pin

    2007-01-01

    The inclusion complex formation of tanshinone IIA(Tan IIA)with hydroxypropyl-β-cyclodextrin(HPCD)was studied by using phase solubility method,and the formation constant for tanshinone IIA-HPCD- dextrin was determined.The effect of temperature on the reaction was studied through thermodynamics,and the changes inentropy,enthalpy,and free energy of the reaction were calculated.The molecular modeling provided further evidence for the formation of the inclusion complexes.Stable inclusion complex in solid state was characterized by IR spectra.

  14. Regulation of myosin IIA and filamentous actin during insulin-stimulated glucose uptake in 3T3-L1 adipocytes

    Energy Technology Data Exchange (ETDEWEB)

    Stall, Richard; Ramos, Joseph; Kent Fulcher, F.; Patel, Yashomati M., E-mail: ympatel@uncg.edu

    2014-03-10

    Insulin stimulated glucose uptake requires the colocalization of myosin IIA (MyoIIA) and the insulin-responsive glucose transporter 4 (GLUT4) at the plasma membrane for proper GLUT4 fusion. MyoIIA facilitates filamentous actin (F-actin) reorganization in various cell types. In adipocytes F-actin reorganization is required for insulin-stimulated glucose uptake. What is not known is whether MyoIIA interacts with F-actin to regulate insulin-induced GLUT4 fusion at the plasma membrane. To elucidate the relationship between MyoIIA and F-actin, we examined the colocalization of MyoIIA and F-actin at the plasma membrane upon insulin stimulation as well as the regulation of this interaction. Our findings demonstrated that MyoIIA and F-actin colocalized at the site of GLUT4 fusion with the plasma membrane upon insulin stimulation. Furthermore, inhibition of MyoII with blebbistatin impaired F-actin localization at the plasma membrane. Next we examined the regulatory role of calcium in MyoIIA-F-actin colocalization. Reduced calcium or calmodulin levels decreased colocalization of MyoIIA and F-actin at the plasma membrane. While calcium alone can translocate MyoIIA it did not stimulate F-actin accumulation at the plasma membrane. Taken together, we established that while MyoIIA activity is required for F-actin localization at the plasma membrane, it alone is insufficient to localize F-actin to the plasma membrane. - Highlights: • Insulin induces colocalization of MyoIIA and F-actin at the cortex in adipocytes. • MyoIIA is necessary but not sufficient to localize F-actin at the cell cortex. • MyoIIA-F-actin colocalization is regulated by calcium and calmodulin.

  15. Regulation of myosin IIA and filamentous actin during insulin-stimulated glucose uptake in 3T3-L1 adipocytes

    International Nuclear Information System (INIS)

    Insulin stimulated glucose uptake requires the colocalization of myosin IIA (MyoIIA) and the insulin-responsive glucose transporter 4 (GLUT4) at the plasma membrane for proper GLUT4 fusion. MyoIIA facilitates filamentous actin (F-actin) reorganization in various cell types. In adipocytes F-actin reorganization is required for insulin-stimulated glucose uptake. What is not known is whether MyoIIA interacts with F-actin to regulate insulin-induced GLUT4 fusion at the plasma membrane. To elucidate the relationship between MyoIIA and F-actin, we examined the colocalization of MyoIIA and F-actin at the plasma membrane upon insulin stimulation as well as the regulation of this interaction. Our findings demonstrated that MyoIIA and F-actin colocalized at the site of GLUT4 fusion with the plasma membrane upon insulin stimulation. Furthermore, inhibition of MyoII with blebbistatin impaired F-actin localization at the plasma membrane. Next we examined the regulatory role of calcium in MyoIIA-F-actin colocalization. Reduced calcium or calmodulin levels decreased colocalization of MyoIIA and F-actin at the plasma membrane. While calcium alone can translocate MyoIIA it did not stimulate F-actin accumulation at the plasma membrane. Taken together, we established that while MyoIIA activity is required for F-actin localization at the plasma membrane, it alone is insufficient to localize F-actin to the plasma membrane. - Highlights: • Insulin induces colocalization of MyoIIA and F-actin at the cortex in adipocytes. • MyoIIA is necessary but not sufficient to localize F-actin at the cell cortex. • MyoIIA-F-actin colocalization is regulated by calcium and calmodulin

  16. Antibacterial activity of bacteriocin-like substance P34 on Listeria monocytogenes in chicken sausage

    Directory of Open Access Journals (Sweden)

    Voltaire Sant'Anna

    2013-12-01

    Full Text Available The antimicrobial activity of the bacteriocin-like substance (BLS P34 against Listeria monocytogenes was investigated in chicken sausage. The BLS was applied to chicken sausages (256 AU g-1 previously inoculated with a suspension of 10² cfu g-1 of L. monocytogenes. BLS P34 inhibited the indicator microorganism in situ in all incubation times for up to 10 days at 5 °C. The effectiveness of BLS P34 was increased when it was added in combination with nisin. The bacteriocin was also tested in natural eatable natural bovine wrapping (salty semi-dried tripe against the same indicator microorganism, also showing inhibitory capability in vitro. BLS P34 showed potential to control L. monocytogenes in refrigerated meat products.

  17. Heterotic-Type IIA Duality and Degenerations of K3 Surfaces

    CERN Document Server

    Braun, Andreas P

    2016-01-01

    We study the duality between four-dimensional N=2 compactifications of Heterotic and Type IIA string theories. Via adiabatic fibration of the duality in six dimensions, Type IIA string theory compactified on a K3-fibred Calabi-Yau threefold has a potential heterotic dual compactification. This adiabatic picture fails whenever the K3 fibre degenerates into multiple components. Guided by monodromy, we identify such degenerate K3 fibres as solitons generalizing the NS5-brane in Heterotic string theory. The theory of degenerations of K3 surfaces can then be used to find which solitons can be present on the heterotic side. Similar to small instanton transitions, these solitons convoy singular transitions between different Calabi-Yau threefolds. Starting from well-known examples of Heterotic-Type IIA duality, such transitions can take us to Type IIA compactifications with unknown heterotic duals.

  18. Heterotic-type IIA duality and degenerations of K3 surfaces

    Science.gov (United States)

    Braun, A. P.; Watari, T.

    2016-08-01

    We study the duality between four-dimensional N = 2 compactifications of heterotic and type IIA string theories. Via adiabatic fibration of the duality in six dimensions, type IIA string theory compactified on a K3-fibred Calabi-Yau threefold has a potential heterotic dual compactification. This adiabatic picture fails whenever the K3 fibre degenerates into multiple components over points in the base of the fibration. Guided by monodromy, we identify such degenerate K3 fibres as solitons generalizing the NS5-brane in heterotic string theory. The theory of degenerations of K3 surfaces can then be used to find which solitons can be present on the heterotic side. Similar to small instanton transitions, these solitons escort singular transitions between different Calabi-Yau threefolds. Starting from well-known examples of heterotic-type IIA duality, such transitions can take us to type IIA compactifications with unknown heterotic duals.

  19. Bacteriocin-resistant mutants of Erwinia chrysanthemi: possible involvement of iron acquisition in phytopathogenicity.

    OpenAIRE

    Expert, D; A. Toussaint

    1985-01-01

    A series of bacteriocin-resistant mutants of Erwinia chrysanthemi 3937JRH were unable to elicit soft-rot symptoms on saintpaulia plants. The loss of pathogenicity was correlated with the disappearance of one to three outer membrane polypeptides (molecular weights, about 80,000 to 90,000) whose production in wild-type strains was greatly enhanced under iron-limited growth conditions. The mutants did not exhibit altered extracellular pectinolytic or cellulolytic activities.

  20. Production of bacteriocin-like substances by lactic acid bacteria isolated from regional ovine cheese

    OpenAIRE

    Cássia Regina Nespolo; Adriano Brandelli

    2010-01-01

    Lactic acid bacteria (LAB) were isolated from ovine milk and cheeses manufactured in the South Region of Brazil. Among 112 bacterial isolates investigated, 59 were chosen through a screening for LAB. Among these 59 strains of LAB, 21% showed antimicrobial, proteolytic and lipolytic activities. Based on this screening, Lactobacillus plantarum LCN 17 and Lactobacillus rhamnosus LCN 43 were selected and tested for the production of bacteriocin-like substances (BLS). The BLS produced by both isol...

  1. Lactococcin G is a potassium ion-conducting, two-component bacteriocin.

    OpenAIRE

    Moll, Gert; Ubbink-Kok, Trees; Hildeng-Hauge, Håvard; Nissen-Meyer, Jon; Nes, Ingolf F.; Konings, Wil N.; Arnold J M Driessen

    1996-01-01

    Lactococcin G is a novel lactococcal bacteriocin whose activity depends on the complementary action of two peptides, termed alpha and beta. Peptide synthesis of the alpha and beta peptides yielded biologically active lactococcin G, which was used in mode-of-action studies on sensitive cells of Lactococcus lactis. Approximately equivalent amounts of both peptides were required for optimal bactericidal effect. No effect was observed with either the alpha or beta peptide in the absence of the co...

  2. Complete genome sequence of Enterococcus faecalis LD33, a bacteriocin-producing strain.

    Science.gov (United States)

    Yuehua, Jiao; Lanwei, Zhang; Fei, Liu; Huaxi, Yi; Xue, Han

    2016-06-10

    Enterococcus faecalis LD33 strain was originally isolated from traditional naturally fermented cream in Inner Mongolia of China. Its complete genome sequence was carried out using the Illumina Hiseq and the PacBio RSII platform. The genome only has a circular chromosome and a GC content of 37.58%. Other core information shown in the genome sequencing results further insight on this bacterium's genetic elements for bacteriocin production and the genes related to respiratory chain. PMID:27090021

  3. Bacteriocins from lactic acid bacteria: purification, properties and use as biopreservatives

    OpenAIRE

    José Luis Parada; Carolina Ricoy Caron; Adriane Bianchi P. Medeiros; Carlos Ricardo Soccol

    2007-01-01

    Biopreservation systems in foods are of increasing interest for industry and consumers. Bacteriocinogenic lactic acid bacteria and/or their isolated bacteriocins are considered safe additives (GRAS), useful to control the frequent development of pathogens and spoiling microorganisms in foods and feed. The spreading of bacterial antibiotic resistance and the demand for products with fewer chemicals create the necessity of exploring new alternatives, in order to reduce the abusive use of therap...

  4. Bacteriocin-resistant mutants of Erwinia chrysanthemi: possible involvement of iron acquisition in phytopathogenicity.

    Science.gov (United States)

    Expert, D; Toussaint, A

    1985-07-01

    A series of bacteriocin-resistant mutants of Erwinia chrysanthemi 3937JRH were unable to elicit soft-rot symptoms on saintpaulia plants. The loss of pathogenicity was correlated with the disappearance of one to three outer membrane polypeptides (molecular weights, about 80,000 to 90,000) whose production in wild-type strains was greatly enhanced under iron-limited growth conditions. The mutants did not exhibit altered extracellular pectinolytic or cellulolytic activities. PMID:4008442

  5. Dynamics of a Model of Allelopathy and Bacteriocin with a Single Mutation

    OpenAIRE

    Zou, Lan; Chen, Xingwu; Ruan, Shigui; Zhang, Weinian

    2011-01-01

    In this paper we discuss a model of allelopathy and bacteriocin in the chemostat with a wild-type organism and a single mutant. Dynamical properties of this model show the basic competition between two microorganisms. A qualitative analysis about the boundary equilibrium, a state that microorganisms both vanish, is carried out. The existence and uniqueness of the interior equilibrium are proved by a technical reduction to the singularity of a matrix. Its dynamical properties are given by usin...

  6. Production, purification, and properties of a bacteriocin from Staphylococcus aureus isolated from saliva.

    OpenAIRE

    Nakamura, T.(International Center for Elementary Particle Physics and Department of Physics, The University of Tokyo, Tokyo, Japan); Yamazaki, N; Taniguchi, H; Fujimura, S.

    1983-01-01

    Staphylococci from samples of human saliva were isolated on staphylococcal-selective agar plates. These strains were tested for the inhibition of the growth of Staphylococcus aureus FDA209P. The frequency of inhibitory strains among all of the staphylococcal isolates was 5.2%. Strain IYS2, which formed the biggest inhibitory zone against the growth of the indicator strain, was used as the producer of bacteriocin. IYS2 was identified to be S. aureus, based on its biological properties. The bac...

  7. Genotypic and Phylogenic Analysis of Lactobacilli Producing Bacteriocin Isolated from Traditional Dairy Products and Food

    OpenAIRE

    Frazaneh Tafvizi; Maryam Tajabadi Ebrahimi; Leila Khojare

    2012-01-01

    Background & Objective: Lactic acid bacteria (LAB) are a group of Gram-positive, non-spore forming, cocci or rod shaped, catalase negative organisms, considered as Generally Recognized as Safe (GRAS) organisms. These bacteria are used for thousands of years for production of fermented foods because of their ability to produce desirable changes in taste, flavor and texture. Different antimicrobial molecules such as bacteriocins produced by these bacteria that can inhibit food pathogens, so enh...

  8. Can electrophoretic types of listeria monocytogenes induce different sensitivity to lactic acid bacteria bacteriocins?

    Directory of Open Access Journals (Sweden)

    Dimitrijević Mirjana

    2005-01-01

    Full Text Available The aim of this study was to find if electrophoretic types (ETs of Listeria monocytogenes, typed by multilocus enzyme electrophoresis (MEE, can induce different sensitivity to lactic acid bacteria bacteriocins. Bacteriocins are extracellular peptides or protein molecules, produced by lactic acid bacteria, which not only have bactericidal or bacteriostatic effects, on usually closely related bacterial strains, but also they may have destructive effects on some not so closely related Gram positive bacteria, for example Listeria monocytogenes. Listeria monocytogenes is commonly found in the intestines of humans and animals, in milk, soil, leafy vegetables and in food processing environments. These bacteria have been isolated in a variety of foods, including raw and cooked poultry, meat, seafood, salads and sandwiches. Many techniques for typing of Listeria monocytogenes in foodstuffs, have been developed for the purpose of identification of the origin of infection for epidemiological and epizootological studies. Among the 98 examined isolates of Listeria monocytogenes (50 clinical/human and 48 from food of animal origin 32 electrophoretic types have been detected. Bacteriocins, which we have used in the study, originated from the following lacic acid bacteria: Lactobacillus sake 148, Lactococcus UW, Lactobacillus sake 706, Pediococcus 347 and Lactobacillus sake 265. In this study, on the basis of a dendogram, our results indicate that a reliable relationship between genetic distance of Listeria monocytogenes electrophoretic types and their sensitivity to lactic acid bacteria bacteriocins cannot been found. MEE may, however, be of future benefit in establishing links between isolates from human disease cases and thus be useful in establishing the epidemiology of not only sporadic cases, but of outbreaks of listeriosis, as well.

  9. Tanshinone IIA ameliorates dextran sulfate sodium-induced inflammatory bowel disease via the pregnane X receptor

    Directory of Open Access Journals (Sweden)

    Zhang X

    2015-12-01

    Full Text Available Xianxie Zhang,1 Yuguang Wang,2 Zengchun Ma,2 Qiande Liang,2 Xianglin Tang,2 Donghua Hu,2 Hongling Tan,2 Chengrong Xiao,2 Yue Gao2 1Air Force General Hospital of People’s Liberation Army, Beijing, People’s Republic of China; 2Department of Pharmacology and Toxicology, Beijing Institute of Radiation Medicine, Beijing, People’s Republic of China Abstract: Tanshinone IIA (Tan IIA (C19H18O3 is one of the major active lipophilic components in a conventional Chinese medicine called danshen, and it has long been used in the People’s Republic of China and other neighboring countries to treat patients suffering from inflammatory bowel disease (IBD. Previous experiments by many teams determined which mechanism of Tan IIA is relevant to the treatment of IBD associated with inflammation and the pregnane X receptor (PXR. The current study demonstrated that Tan IIA is an efficacious PXR agonist and its ability to induce CYP3A4 mRNA and protein expression was mediated by the transactivation of PXR, a known target of abrogating inflammation in IBD. Clinical symptoms in mice and histological assessment data suggested that administration of Tan IIA in mice demonstrated significant protection and showed that in DSS-induced IBD it acts in a concentration-dependent manner. PXR-silenced mice treated with Tan IIA demonstrated low protection against DSS-induced mouse IBD and exacerbated the severity of IBD compared with wild-type mice; PXR-silenced mice demonstrated the necessity for PXR in Tan IIA-mediated upregulation of xenobiotic metabolism genes. The IBD treatment effects of Tan IIA are partially due to PXR-mediated upregulation of xenobiotic metabolism and downregulation of inflammatory mediators. The novel findings reported here may contribute to the effective utilization of Tan IIA and its derivatives as a PXR ligand in the treatment of human IBD. This suggests that Tan IIA may have considerable clinical utility. Keywords: dashen, ulcerative colitis

  10. Protective effects of tanshinone IIA on endothelial progenitor cells injured by tumor necrosis factor-α

    OpenAIRE

    Wang, Xing-xiang; YANG, JIN-XIU; PAN, YAN-YUN; ZHANG, YE-FEI

    2015-01-01

    Tanshinone IIA (Tan IIA) is a Traditional Chinese Medicine commonly used in Asian and Western countries for the prevention and treatment of cardiovascular disorders, such as atherosclerosis. Endothelial dysfunction and associated inflammatory processes have a critical role in the development of atherosclerosis. Endothelial progenitor cells (EPCs) have been demonstrated to be involved in certain aspects of the endothelial repair process. The present study aimed to investigate the putative prot...

  11. Low frequency solar radio astronomy at the Indian Institute of Astrophysics (IIA)

    Science.gov (United States)

    Ramesh, R.

    IIA is presently involved in the expansion of its existing radioheliograph operating in the frequency 120-40 MHz at the Gauribidanur radio observatory located about 80 km north of Bangalore. Once completed, the expanded array will have an angular resolution of ≈ 1' at a typical frequency of 100 MHz. This paper describes the development of solar radio astronomy activities at IIA since 1952 when the first observations were carried out.

  12. Point of care testing of phospholipase A2 group IIA for serological diagnosis of rheumatoid arthritis

    Science.gov (United States)

    Liu, Nathan J.; Chapman, Robert; Lin, Yiyang; Mmesi, Jonas; Bentham, Andrew; Tyreman, Matthew; Abraham, Sonya; Stevens, Molly M.

    2016-02-01

    Secretory phospholipase A2 group IIA (sPLA2-IIA) was examined as a point of care marker for determining disease activity in rheumatoid (RA) and psoriatic (PsA) arthritis. Serum concentration and activity of sPLA2-IIA were measured using in-house antibodies and a novel point of care lateral flow device assay in patients diagnosed with varying severities of RA (n = 30) and PsA (n = 25) and found to correlate strongly with C-reactive protein (CRP). Levels of all markers were elevated in patients with active RA over those with inactive RA as well as both active and inactive PsA, indicating that sPLA2-IIA can be used as an analogue to CRP for RA diagnosis at point of care.Secretory phospholipase A2 group IIA (sPLA2-IIA) was examined as a point of care marker for determining disease activity in rheumatoid (RA) and psoriatic (PsA) arthritis. Serum concentration and activity of sPLA2-IIA were measured using in-house antibodies and a novel point of care lateral flow device assay in patients diagnosed with varying severities of RA (n = 30) and PsA (n = 25) and found to correlate strongly with C-reactive protein (CRP). Levels of all markers were elevated in patients with active RA over those with inactive RA as well as both active and inactive PsA, indicating that sPLA2-IIA can be used as an analogue to CRP for RA diagnosis at point of care. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr08423g

  13. Partial Characterization of Bacteriocins Produced by Two New Enterococcus faecium Isolated from Human Intestine.

    Science.gov (United States)

    Turgis, Mélanie; Vu, Khanh Dang; Lacroix, Monique

    2013-06-01

    This study aimed at characterizing two novel bacteriocin-producing enterococcal strains isolated from human intestine. A total of 200 lactic acid bacteria were isolated from a woman stool sample. Two of them were selected for characterization due to their high antimicrobial activity against five strains of Listeria monocytogenes. The selected bacteria were identified as two different strains of Enterococcus faecium and designated MT 104 and MT 162. The bacteriocins produced by MT 104 and MT 162 were stable at different pH ranging from 2 to 11 and were active after different treatments such as heat, enzymes, detergents, and γ-irradiation. The two isolated strains exhibited some probiotic properties such as survival in simulated gastric fluid and intestinal fluid, lack of expression of bile salt hydrolase or hemolytic activity, adhesion to Caco-2 cells efficiently, and sensitivity to clinical antimicrobial agents. Thus, the two isolated strains of E. faecium could become new probiotic bacteria and their bacteriocins could be used for controlling L. monocytogenes in combination with irradiation for food preservation. PMID:26782736

  14. Simultaneous Production of Biosurfactants and Bacteriocins by Probiotic Lactobacillus casei MRTL3

    Directory of Open Access Journals (Sweden)

    Deepansh Sharma

    2014-01-01

    Full Text Available Lactic acid bacteria (LAB are ubiquitous and well-known commensal bacteria in the human and animal microflora. LAB are extensively studied and used in a variety of industrial and food fermentations. They are widely used for humans and animals as adjuvants, probiotic formulation, and dietary supplements and in other food fermentation applications. In the present investigation, LAB were isolated from raw milk samples collected from local dairy farms of Haryana, India. Further, the isolates were screened for simultaneous production of biosurfactants and bacteriocins. Biosurfactant produced was found to be a mixture of lipid and sugar similar to glycolipids. The bacteriocin obtained was found to be heat stable (5 min at 100°C. Further, DNA of the strain was extracted and amplified by the 16S rRNA sequencing using universal primers. The isolate Lactobacillus casei MRTL3 was found to be a potent biosurfactant and bacteriocin producer. It seems to have huge potential for food industry as a biopreservative and/or food ingredient.

  15. Isolation of bacteriocins through expanded bed adsorption using a hydrophobic interaction medium.

    Science.gov (United States)

    Remedios, M; Moreno, F; Callewaert, R; De Vuyst, L

    2001-01-01

    Two lactic acid bacterium bacteriocins were isolated from fermentation medium through expanded bed adsorption using a hydrophobic interaction gel. First, amylovorin L471, produced by Lactobacillus amylovorus DCE 471, was selected for the optimisation of the loading and eluting conditions. Secondly, the results of the optimisation were applied for the isolation of enterocin RZS C5, a bacteriocin produced by Enterococcusfaecium RZS C5. Optimal adsorption was obtained for a medium with concentration of 1.0 M ammonium sulphate and adjusted to pH 4.0 (94.9% for amylovorin L471 and 75.0% for enterocin RZS C5). Elution with 50% ethanol, buffered at pH 6.0, resulted in an optimal total recovery of the bacteriocin activity of 47.6 and 57.6%, respectively. The highest fold purification expressed as the increase in specific activity (AU/mg) corresponded to the highest recovery, being 140- and 1677-fold, respectively. Nevertheless, a total recovery of only 25.6% with an increase of the specific activity of 121 times was obtained after conventional isolation by ammonium sulphate precipitation. PMID:11787796

  16. Biphasic kinetics of growth and bacteriocin production with Lactobacillus amylovorus DCE 471 occur under stress conditions.

    Science.gov (United States)

    Neysens, Patricia; Messens, Winy; Gevers, Dirk; Swings, Jean; De Vuyst, Luc

    2003-04-01

    Micro-organisms used during the production of fermented foods are subjected to several abiotic stresses. Microbial survival during these processes strongly depends on the ability of the cells to adapt and become more tolerant to the environmental conditions. Cultivation of Lactobacillus amylovorus DCE 471, a potential strain for use during type II sourdough fermentations, at low temperatures, unfavourable pH and high salt concentrations resulted in biphasic growth patterns. In addition, two separate bacteriocin peaks, as well as a dramatic change in cellular morphology, were observed. In general, an increase of the specific bacteriocin production occurred during the second growth phase. Finally, the observed sugar consumption profiles were affected by the applied fermentation temperature. Moreover, the highest bacteriocin activity occurred during maltose consumption at a low constant temperature of 28 degrees C and a constant pH of 5.4. Plate counts from both growth phases revealed the existence of two colony types. Irregular colonies were found to outnumber smoother colonies during the first growth phase, while the second growth phase was characterized by a greater number of smooth colonies. Electron microscopy was used to investigate the observed morphological switch at the single-cell level. Single, rod-shaped cells changed into elongated cells that grew in chains. Colony and cell morphology changes coincided with the biphasic growth pattern. PMID:12686649

  17. Plantaricin LD1: a bacteriocin produced by food isolate of Lactobacillus plantarum LD1.

    Science.gov (United States)

    Gupta, Aabha; Tiwari, Santosh Kumar

    2014-04-01

    Plantaricin LD1, a bacteriocin produced by Lactobacillus plantarum LD1, was characterized for biochemical and antimicrobial properties. Bacteriocin showed stability at high temperatures (100 °C for 20 min and 121 °C for 15 min under 15 psi pressure), in a pH range of 2.0-8.0 and also in the presence of organic solvents, surfactants and detergents. The crude preparation was not affected by catalase, amylase and lipase but activity was reduced in the presence of pepsin, trypsin and proteinase K showing proteinaceous nature of the compound. The molecular weight of bacteriocin was found to be ∼6.5 kDa, and antimicrobial activity was confirmed by bioassay. It inhibited not only related strains but also other Gram-positive and Gram-negative bacteria such as Lactobacillus curvatus NRRL B-4562, Lactococcus lactis subsp. lactis NRRL B-1821, Enterococcus faecium NRRL B-2354, Enterobacter cloacae NRRL B-14298, Micrococcus luteus, Staphylococcus aureus, urogenic Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi, Shigella flexneri and Vibrio sp. These properties of plantaricin LD1 suggest its applications not only in food safety but in therapeutics as well. PMID:24522411

  18. 广谱抗菌肽——片球菌素pediocin PA-1%Pediocin PA-1, a wide-spectrum bacteriocin from lactic acid bacteria

    Institute of Scientific and Technical Information of China (English)

    吕燕妮

    2011-01-01

    Pediocin PA-1 is a broad-spectrum lactic acid bacteria bacteriocin that shows a particularly strong activity against Listeria monocytogenes, a foodborne pathogen of special concern among the food industrys. This antimicrobial peptide is the most extensively studied class Ⅱa bacteriocin, and it has been sufficiently well characterized to be used as a food biopreservative. This review focuses on the progress that have been made in the elucidations of its structure and mode of action, includes an overview of its applications in food systems. In the future, protein engineering, genetic engineering and chemical synthesis may lead to the development of new antimicrobial peptides with improved properties, based on some features of the pediocin PA-1 molecule.%片球菌素PA-1是一种广谱的乳酸菌细菌素,它对食品工业中的腐败菌单核细胞增生李斯特氏菌有强烈的抑制作用,是Ⅱa类细菌素中研究最深入的一种抗菌肽,具有很好的作为食品生物防腐剂开发的应用前景。对近年来关于片球菌素PA-1的结构、作用方式及在食品中的应用作一综述,并对其未来的应用前景,在蛋白质工程、基因工程和化学合成方面进行性质改进做出了展望。

  19. Myosin IIA deficient cells migrate efficiently despite reduced traction forces at cell periphery

    Directory of Open Access Journals (Sweden)

    Melissa H. Jorrisch

    2013-02-01

    Cell motility is a cornerstone of embryogenesis, tissue remodeling and repair, and cancer cell invasion. It is generally thought that migrating cells grab and exert traction force onto the extracellular matrix in order to pull the cell body forward. While previous studies have shown that myosin II deficient cells migrate efficiently, whether these cells exert traction forces during cell migration in the absence of the major contractile machinery is currently unknown. Using an array of micron-sized pillars as a force sensor and shRNA specific to each myosin II isoform (A and B, we analyzed how myosin IIA and IIB individually regulate cell migration and traction force generation. Myosin IIA and IIB localized preferentially to the leading edge where traction force was greatest, and the trailing edge, respectively. When individual myosin II isoforms were depleted by shRNA, myosin IIA deficient cells lost actin stress fibers and focal adhesions, whereas myosin IIB deficient cells maintained similar actin organization and focal adhesions as wild-type cells. Interestingly, myosin IIA deficient cells migrated faster than wild-type or myosin IIB deficient cells on both a rigid surface and a pillar array, yet myosin IIA deficient cells exerted significantly less traction force at the leading edge than wild-type or myosin IIB deficient cells. These results suggest that, in the absence of myosin IIA mediated force-generating machinery, cells move with minimal traction forces at the cell periphery, thus demonstrating the remarkable ability of cells to adapt and migrate.

  20. Influence of Tanshinone IIA on the Apoptosis of Human Esophageal Ec-109 Cells.

    Science.gov (United States)

    Zhu, Yan-Qin; Wang, Bai-Yan; Wu, Fang; An, Yong-Kang; Zhou, Xin-Qiang

    2016-01-01

    The induced-apoptosis effect and mechanism of human esophageal cancer Ec-109 cells via tanshinone IIA was investigated. The Ec-109 cells were cultured in vitro with different concentrations of tanshinone IIA (2 µg/mL, 4 µg/mL, or 8 µg/mL) for 12, 24, 36, and 48 hours. MTT assay was used to evaluate the proliferative inhibition rate of tanshinone IIA on esophageal Ec-109 cells. After 24 hours of culturing in vitro, a control group was assigned. The apoptosis rate was detected by the AO/EB and annexin V-FITC/propidium iodide assay, and the protein levels of Caspase-4 and CHOP were determined by the Western blot technique. MTT data showed that tanshinone IIA could significantly inhibit the proliferation of Ec-109 cells with a dose- and time-dependent mode. Compared with the control group, tanshinone IIA could apparently induce apoptosis of Ec-109 cells, and the level of Caspase-4 and CHOP (p < 0.01) obviously increased. Tanshinone IIA can significantly induce the apoptosis of Ec-109 cells, which may take effect by the stress pathway of the endoplasmic reticulum. PMID:26996008

  1. Development of intravenous lipid emulsion of tanshinone IIA and evaluation of its anti-hepatoma activity in vitro.

    Science.gov (United States)

    Chu, Ting; Zhang, Qing; Li, Hui; Ma, Wei-cong; Zhang, Na; Jin, Hui; Mao, Sheng-jun

    2012-03-15

    The purpose of this study was to develop a lipid emulsion of tanshinone IIA (Tan IIA-LE) for intravenous administration and to investigate its feasibility for future clinical practice. The formulation was optimized using central composite design-response surface methodology (CCD-RSM), and the homogenization process was investigated systematically. The Tan IIA-LE was evaluated in terms of stability, safety and in vitro anti-hepatoma activity. The formulation of Tan IIA-LE is composed of 0.05% (w/v) Tan IIA, 20% (w/v) soybean oil-MCT mixture (1:1, w/w), 1.2% (w/v) soybean lecithin, 0.3% (w/v) F68 and 2.2% (w/v) glycerol, a high pressure homogenization at 100 MPa for 3 cycles was selected as the optimal homogenization process. The Tan IIA-LE was light-sensitive but stable for at least 12 months at room temperature in dark. The safety study demonstrated that the Tan IIA-LE did not cause venous irritation or obvious acute toxicity. Furthermore, the Tan IIA-LE displayed significant anti-tumor activity against human hepatoma cell lines in vitro. Overall, the Tan IIA-LE developed in this study was suggested to be a suitable and safe dosage form of Tan IIA for intravenous administration and has potential in liver cancer therapy in future. PMID:22226873

  2. Type IIA flux compactifications. Vacua, effective theories and cosmological challenges

    Energy Technology Data Exchange (ETDEWEB)

    Koers, Simon

    2009-07-30

    In this thesis, we studied a number of type IIA SU(3)-structure compactifications with 06-planes on nilmanifolds and cosets, which are tractable enough to allow for an explicit derivation of the low energy effective theory. In particular we calculated the mass spectrum of the light scalar modes, using N = 1 supergravity techniques. For the torus and the Iwasawa solution, we have also performed an explicit Kaluza-Klein reduction, which led to the same result. For the nilmanifold examples we have found that there are always three unstabilized moduli corresponding to axions in the RR sector. On the other hand, in the coset models, except for SU(2) x SU(2), all moduli are stabilized. We discussed the Kaluza-Klein decoupling for the supersymmetric AdS vacua and found that it requires going to the Nearly-Calabi Yau limited. We searched for non-trivial de Sitter minima in the original flux potential away from the AdS vacuum. Finally, in chapter 7, we focused on a family of three coset spaces and constructed non-supersymmetric vacua on them. (orig.)

  3. Type IIA orientifolds on SU(2)-structure manifolds

    International Nuclear Information System (INIS)

    We investigate the possible supersymmetry-preserving orientifold projections of type IIA string theory on a six-dimensional background with SU(2)-structure. We find two categories of projections which preserve half of the low-energy supersymmetry, reducing the effective theory from an N=4 supergravity theory, to an N=2 supergravity. For these two cases, we impose the projection on the low-energy spectrum and reduce the effective N=4 supergravity action accordingly. We can identify the resulting gauged N=2 supergravity theory and bring the action into canonical form. We compute the scalar moduli spaces and characterize the gauged symmetries in terms of the geometry of these moduli spaces. Due to their origin in N=4 supergravity, which is a highly constrained theory, the moduli spaces are of a very simple form. We find that, for suitable background manifolds, isometries in all scalar sectors can become gauged. The obtained gaugings share many features with those of N=2 supergravities obtained previously from other G-structure compactifications. (orig.)

  4. Type IIA flux compactifications. Vacua, effective theories and cosmological challenges

    International Nuclear Information System (INIS)

    In this thesis, we studied a number of type IIA SU(3)-structure compactifications with 06-planes on nilmanifolds and cosets, which are tractable enough to allow for an explicit derivation of the low energy effective theory. In particular we calculated the mass spectrum of the light scalar modes, using N = 1 supergravity techniques. For the torus and the Iwasawa solution, we have also performed an explicit Kaluza-Klein reduction, which led to the same result. For the nilmanifold examples we have found that there are always three unstabilized moduli corresponding to axions in the RR sector. On the other hand, in the coset models, except for SU(2) x SU(2), all moduli are stabilized. We discussed the Kaluza-Klein decoupling for the supersymmetric AdS vacua and found that it requires going to the Nearly-Calabi Yau limited. We searched for non-trivial de Sitter minima in the original flux potential away from the AdS vacuum. Finally, in chapter 7, we focused on a family of three coset spaces and constructed non-supersymmetric vacua on them. (orig.)

  5. Type IIA orientifolds on SU(2)-structure manifolds

    Energy Technology Data Exchange (ETDEWEB)

    Danckaert, Thomas

    2010-11-15

    We investigate the possible supersymmetry-preserving orientifold projections of type IIA string theory on a six-dimensional background with SU(2)-structure. We find two categories of projections which preserve half of the low-energy supersymmetry, reducing the effective theory from an N=4 supergravity theory, to an N=2 supergravity. For these two cases, we impose the projection on the low-energy spectrum and reduce the effective N=4 supergravity action accordingly. We can identify the resulting gauged N=2 supergravity theory and bring the action into canonical form. We compute the scalar moduli spaces and characterize the gauged symmetries in terms of the geometry of these moduli spaces. Due to their origin in N=4 supergravity, which is a highly constrained theory, the moduli spaces are of a very simple form. We find that, for suitable background manifolds, isometries in all scalar sectors can become gauged. The obtained gaugings share many features with those of N=2 supergravities obtained previously from other G-structure compactifications. (orig.)

  6. Tanshinone IIA attenuates experimental autoimmune encephalomyelitis in rats.

    Science.gov (United States)

    Yan, Jun; Yang, Xue; Han, Dong; Feng, Juan

    2016-08-01

    Multiple sclerosis (MS) is an inflammatory autoimmune neurodegenerative disease, which features focal demyelination and inflammatory cell infiltration of the brain and the spinal cord. Tanshinone IIA (TSIIA), one of the major fat‑soluble components of Salvia miltiorrhiza (Danshen), has anti‑inflammatory, immunoregulatory and neuroprotective activity; however, its efficacy in MS remains unknown. The current study was designed to investigate the potential therapeutic function of TSIIA on MS in the experimental autoimmune encephalomyelitis (EAE) rat model. In comparison to the vehicle control group, the TSIIA‑treated groups showed notably improved clinical symptoms and pathological changes, including central nervous system inflammatory cell infiltration and demyelination. Following administration of TSIIA, the quantity of CD4+ T cells, CD8+ T cells and macrophages/microglia in the spinal cord were reduced to different extents. Furthermore, TSIIA was also shown to downregulate interleukin (IL)‑17 and IL‑23 levels in the brain and serum of EAE rats. The results collectively provide evidence that TSIIA alleviates EAE and support its utility as a novel therapy for MS. PMID:27357729

  7. Differential expression of the cytotoxic and hemolytic activities of the ApxIIA toxin from Actinobacillus pleuropneumoniae.

    OpenAIRE

    Tu, A H; Hausler, C; Young, R.; Struck, D K

    1994-01-01

    The ApxIIA protein secreted from Actinobacillus pleuropneumoniae is both hemolytic and cytotoxic. However, when the cloned apxII operon is expressed in Escherichia coli, two forms of the ApxIIA protein can be recovered. Toxin which remains intracellular has hemolytic and cytotoxic activities, while toxin that is secreted is cytotoxic with little or no hemolytic activity. This indicates that the cytotoxicity of ApxIIA is independent of its hemolytic activity.

  8. Purification and biochemical characterization of a secreted group IIA chicken intestinal phospholipase A2

    OpenAIRE

    Gargouri Youssef; Ben Ali Yassine; Frikha Fakher; Karray Aida; Bezzine Sofiane

    2011-01-01

    Abstract Background Secretory phospholipase A2 group IIA (IIA PLA2) is a protein shown to be highly expressed in the intestine of mammals. However, no study was reported in birds. Results Chicken intestinal group IIA phospholipase A2 (ChPLA2-IIA) was obtained after an acidic treatment (pH.3.0), precipitation by ammonium sulphate, followed by sequential column chromatographies on Sephadex G-50 and mono-S ion exchanger. The enzyme was found to be a monomeric protein with a molecular mass of aro...

  9. Tanshinone IIA Induces Heme Oxygenase 1 Expression and Inhibits Cyclic Strain-Induced Interleukin 8 Expression in Vascular Endothelial Cells.

    Science.gov (United States)

    Zhuang, Shaowei; Cheng, Tzu-Hurng; Shih, Nang-Lang; Liu, Ju-Chi; Chen, Jin-Jer; Hong, Hong-Jye; Chan, Paul

    2016-04-01

    Tanshinone IIA is the main effective component of Salvia miltiorrhiza, known as "Danshen," which has been used in many therapeutic remedies in traditional Chinese medicine. However, the direct effects of tanshinone IIA on vascular endothelial cells have not yet been fully described. In the present study, we demonstrated that tanshinone IIA increased heme oxygenase-1 (HO-1) expression in human umbilical vein endothelial cells. Western blot analyses and experiments with specific inhibitors indicated tanshinone IIA enhanced HO-1 expression through the activation of phosphoinositide 3-kinase (PI3K)/Akt and the subsequent induction of nuclear factor erythroid 2-related factor 2 (Nrf2) nuclear translocation. In addition, tanshinone IIA inhibited cyclic strain induced interleukin-8 (IL-8) expression. HO-1 silencing significantly abrogated the repressive effects of tanshinone IIA on strain-induced IL-8 expression, which suggests HO-1 has a role in mediating the effects of tanshinone IIA. This study reports for the first time that tanshinone IIA inhibits cyclic strain-induced IL-8 expression via the induction of HO-1 in endothelial cells, providing valuable new insight into the molecular pathways that may contribute to the effects of tanshinone IIA. PMID:27080946

  10. A strain-variable bacteriocin in Bacillus anthracis and Bacillus cereus with repeated Cys-Xaa-Xaa motifs

    Directory of Open Access Journals (Sweden)

    Haft Daniel H

    2009-04-01

    Full Text Available Abstract Bacteriocins are peptide antibiotics from ribosomally translated precursors, produced by bacteria often through extensive post-translational modification. Minimal sequence conservation, short gene lengths, and low complexity sequence can hinder bacteriocin identification, even during gene calling, so they are often discovered by proximity to accessory genes encoding maturation, immunity, and export functions. This work reports a new subfamily of putative thiazole-containing heterocyclic bacteriocins. It appears universal in all strains of Bacillus anthracis and B. cereus, but has gone unrecognized because it is always encoded far from its maturation protein operon. Patterns of insertions and deletions among twenty-four variants suggest a repeating functional unit of Cys-Xaa-Xaa. Reviewers This article was reviewed by Andrei Osterman and Lakshminarayan Iyer.

  11. Purification and partial characterization of bacillocin 490, a novel bacteriocin produced by a thermophilic strain of Bacillus licheniformis

    Directory of Open Access Journals (Sweden)

    De Felice Maurilio

    2002-04-01

    Full Text Available Abstract Background Applications of bacteriocins as food preservatives have been so far limited, principally because of their low antimicrobial activity in foods. Nisin is the only bacteriocin of significant use, but applications are restricted principally because of its very low activity at neutral or alkaline pH. Thus the isolation of new bacteriocins active in foods is desirable. Results We isolated a Bacillus licheniformis thermophilic strain producing a bacteriocin with some novel features, named here bacillocin 490. This bacteriocin was inactivated by pronase E and proteinase K and was active against closely related Bacillus spp. both in aerobic and in anaerobic conditions. Bactericidal activity was kept during storage at 4°C and was remarkably stable in a wide pH range. The bacteriocin was partially purified by elution after adhesion to cells of the food-isolated strain Bacillus smithii and had a rather low mass (2 KDa. Antimicrobial activity against B. smithii was observed also when this organism was grown in water buffalo milk. Conclusions Bacillocin 490 is a novel candidate as a food anti-microbial agent since it displays its activity in milk, is stable to heat treatment and during storage, is active in a wide pH range and has bactericidal activity also at high temperature. These features may allow the use of bacillocin 490 during processes performed at high temperature and as a complementary antimicrobial agent of nisin against some Bacillus spp. in non-acidic foods. The small size suggests its use on solid foods.

  12. Purification and amino acid sequence of a bacteriocins produced by Lactobacillus salivarius K7 isolated from chicken intestine

    Directory of Open Access Journals (Sweden)

    Kenji Sonomoto

    2006-03-01

    Full Text Available A bacteriocin-producing strain, Lactobacillus K7, was isolated from a chicken intestine. The inhibitory activity was determined by spot-on-lawn technique. Identification of the strain was performed by morphological, biochemical (API 50 CH kit and molecular genetic (16S rDNA basis. Bacteriocin purification processes were carried out by amberlite adsorption, cation exchange and reverse-phase high perform- ance liquid chromatography. N-terminal amino acid sequences were performed by Edman degradation. Molecular mass was determined by electrospray-ionization (ESI mass spectrometry (MS. Lactobacillus K7 showed inhibitory activity against Lactobacillus sakei subsp. sakei JCM 1157T, Leuconostoc mesenteroides subsp. mesenteroides JCM 6124T and Bacillus coagulans JCM 2257T. This strain was identified as Lb. salivarius. The antimicrobial substance was destroyed by proteolytic enzymes, indicating its proteinaceous structure designated as a bacteriocin type. The purification of bacteriocin by amberlite adsorption, cation exchange, and reverse-phase chromatography resulted in only one single active peak, which was designated FK22. Molecular weight of this fraction was 4331.70 Da. By amino acid sequence, this peptide was homology to Abp 118 beta produced by Lb. salivarius UCC118. In addition, Lb. salivarius UCC118 produced 2-peptide bacteriocin, which was Abp 118 alpha and beta. Based on the partial amino acid sequences of Abp 118 beta, specific primers were designed from nucleotide sequences according to data from GenBank. The result showed that the deduced peptide was high homology to 2-peptide bacteriocin, Abp 118 alpha and beta.

  13. EFFECT OF CULTURE MEDIUM ON BACTERIOCIN PRODUCTION BY LACTOBACILLUS RHAMNOSUS HN001 AND LACTOBACILLUS REUTERI ATCC 53608

    OpenAIRE

    Aguilar-Uscanga B. R.; Solís-Pacheco J. R.; Plascencia L.; Aguilar-Uscanga M. G.; García H. S.; Lacroix M.

    2013-01-01

    The aim of this study was to evaluate the effect of media on bacteriocin production by Lactobacillus rhamnosus HN001 and Lactobacillus reuteri ATCC 53608 using three different media: YPM, YPF and MRS supplemented with glucose and K2HPO4. The optimum temperature was 37°C and initial pH 6.5. Bacteriocin-like substances produced by tested bacteria in MRS medium supplemented with glucose and K2HPO4 exhibited a broad antimicrobial spectrum determined by well diffusion assay against indicator bacte...

  14. Complete genome sequence of Lactobacillus plantarum LZ95, a potential probiotic strain producing bacteriocins and B-group vitamin riboflavin.

    Science.gov (United States)

    Li, Ping; Gu, Qing

    2016-07-10

    Lactobacillus plantarum LZ95 is a potential probiotic isolated from newborn infant fecal and it is identified to produce riboflavin with great antimicrobial activity. The complete genome sequence of this strain was reported in the present study. The genome contains a 3,261,418-bp chromosome and two plasmids. Genes, related to the biosynthesis of bacteriocins and riboflavin, were identified. This work will facilitate to reveal the biosynthetic mechanism of bacteriocins and B-group vitamins in lactic acid bacteria and provide evidence for its potential application in food industry. PMID:27140869

  15. Escherichia coli bacteriocins: antimicrobial efficacy and prevalence among isolates from patients with bacteraemia.

    Directory of Open Access Journals (Sweden)

    Maruška Budič

    Full Text Available Bacteriocins are antimicrobial peptides generally active against bacteria closely related to the producer. Escherichia coli produces two types of bacteriocins, colicins and microcins. The in vitro efficacy of isolated colicins E1, E6, E7, K and M, was assessed against Escherichia coli strains from patients with bacteraemia of urinary tract origin. Colicin E7 was most effective, as only 13% of the tested strains were resistant. On the other hand, 32%, 33%, 43% and 53% of the tested strains exhibited resistance to colicins E6, K, M and E1. Moreover, the inhibitory activity of individual colicins E1, E6, E7, K and M and combinations of colicins K, M, E7 and E1, E6, E7, K, M were followed in liquid broth for 24 hours. Resistance against individual colicins developed after 9 hours of treatment. On the contrary, resistance development against the combined action of 5 colicins was not observed. One hundred and five E. coli strains from patients with bacteraemia were screened by PCR for the presence of 5 colicins and 7 microcins. Sixty-six percent of the strains encoded at least one bacteriocin, 43% one or more colicins, and 54% one or more microcins. Microcins were found to co-occur with toxins, siderophores, adhesins and with the Toll/Interleukin-1 receptor domain-containing protein involved in suppression of innate immunity, and were significantly more prevalent among strains from non-immunocompromised patients. In addition, microcins were highly prevalent among non-multidrug-resistant strains compared to multidrug-resistant strains. Our results indicate that microcins contribute to virulence of E. coli instigating bacteraemia of urinary tract origin.

  16. Ferredoxin containing bacteriocins suggest a novel mechanism of iron uptake in Pectobacterium spp.

    Directory of Open Access Journals (Sweden)

    Rhys Grinter

    Full Text Available In order to kill competing strains of the same or closely related bacterial species, many bacteria produce potent narrow-spectrum protein antibiotics known as bacteriocins. Two sequenced strains of the phytopathogenic bacterium Pectobacterium carotovorum carry genes encoding putative bacteriocins which have seemingly evolved through a recombination event to encode proteins containing an N-terminal domain with extensive similarity to a [2Fe-2S] plant ferredoxin and a C-terminal colicin M-like catalytic domain. In this work, we show that these genes encode active bacteriocins, pectocin M1 and M2, which target strains of Pectobacterium carotovorum and Pectobacterium atrosepticum with increased potency under iron limiting conditions. The activity of pectocin M1 and M2 can be inhibited by the addition of spinach ferredoxin, indicating that the ferredoxin domain of these proteins acts as a receptor binding domain. This effect is not observed with the mammalian ferredoxin protein adrenodoxin, indicating that Pectobacterium spp. carries a specific receptor for plant ferredoxins and that these plant pathogens may acquire iron from the host through the uptake of ferredoxin. In further support of this hypothesis we show that the growth of strains of Pectobacterium carotovorum and atrosepticum that are not sensitive to the cytotoxic effects of pectocin M1 is enhanced in the presence of pectocin M1 and M2 under iron limiting conditions. A similar growth enhancement under iron limiting conditions is observed with spinach ferrodoxin, but not with adrenodoxin. Our data indicate that pectocin M1 and M2 have evolved to parasitise an existing iron uptake pathway by using a ferredoxin-containing receptor binding domain as a Trojan horse to gain entry into susceptible cells.

  17. Enterococcus faecalis hemolysin-bacteriocin plasmids belong to the same incompatibility group.

    OpenAIRE

    Colmar, I; Horaud, T

    1987-01-01

    Plasmid pair coexistence was studied both among nine Enterococcus faecalis hemolysin-bacteriocin (Hly-Bcn) plasmids, including pJH2, pAD1, pAM gamma 1, and pIP964, and between pIP964 and five R plasmids. Some of the Hly-Bcn plasmids used were derivatives encoding resistance to erythromycin or tetracycline. The Hly-Bcn plasmids were incompatible with each other; 40 to 100% displacement was observed bilaterally for eight pairs and unilaterally for one pair. In contrast, pIP964 stably coexisted ...

  18. Nucleotide sequence and taxonomical distribution of the bacteriocin gene lin cloned from Brevibacterium linens M18.

    OpenAIRE

    Valdes-Stauber, N; Scherer, S

    1996-01-01

    Linocin M18 is an antilisterial bacteriocin produced by the red smear cheese bacterium Brevibacterium linens M18. Oligonucleotide probes based on the N-terminal amino acid sequence were used to locate its single copy gene, lin, on the chromosomal DNA. The amino acid composition, N-terminal sequence, and molecular mass derived from the nucleotide sequence of an open reading frame of 798 nucleotides coding for 266 amino acids found on a 3-kb BamHI restriction fragment correspond closely to thos...

  19. A Case Report of Multiple Endocrine Neoplasia Type IIa Associated with Cushing Syndrome

    Directory of Open Access Journals (Sweden)

    Sh. Borzouei

    2013-10-01

    Full Text Available Introduction: Multiple endocrine neoplasia type IIa (MEN IIa is an autosomal dominant syn-drome characterized bypheochromocytoma ,medullary thyroid carcinoma and hyperparathy-roidism. Pheochromocytoma approximately occurs in 50% of patients with MEN IIa. This tumor has the capacity to produce ACTH ectopically and becomes manifest like Cushing syndrome,although it is very rare. Case Report: We report a 26-year-old woman patient with severe muscle weakness, skin le-sions in extremity, hypertension, new onset diabetes and in the laboratory data hypokalemia, metabolic alkalosis, high serum level of cortisol, metanephrine, normetanephrine, calcitonin and bilateral adrenal mass in computed tomography as the first clinical manifestations of an ACTH-secreting pheochromocytoma. Conclusion: In the patients with hypertension, new onset diabetes and hypokalemia Cushing syndrome and pheochromocytoma should always be ruled out. (Sci J Hamadan Univ Med Sci 2013; 20 (3:260-265

  20. Discovery of Azurin-Like Anticancer Bacteriocins from Human Gut Microbiome through Homology Modeling and Molecular Docking against the Tumor Suppressor p53

    Science.gov (United States)

    Nguyen, Chuong; Nguyen, Van Duy

    2016-01-01

    Azurin from Pseudomonas aeruginosa is known anticancer bacteriocin, which can specifically penetrate human cancer cells and induce apoptosis. We hypothesized that pathogenic and commensal bacteria with long term residence in human body can produce azurin-like bacteriocins as a weapon against the invasion of cancers. In our previous work, putative bacteriocins have been screened from complete genomes of 66 dominant bacteria species in human gut microbiota and subsequently characterized by subjecting them as functional annotation algorithms with azurin as control. We have qualitatively predicted 14 putative bacteriocins that possessed functional properties very similar to those of azurin. In this work, we perform a number of quantitative and structure-based analyses including hydrophobic percentage calculation, structural modeling, and molecular docking study of bacteriocins of interest against protein p53, a cancer target. Finally, we have identified 8 putative bacteriocins that bind p53 in a same manner as p28-azurin and azurin, in which 3 peptides (p1seq16, p2seq20, and p3seq24) shared with our previous study and 5 novel ones (p1seq09, p2seq05, p2seq08, p3seq02, and p3seq17) discovered in the first time. These bacteriocins are suggested for further in vitro tests in different neoplastic line cells.

  1. Thrombin time and anti-IIa dabigatran's activity: hypothesis of thrombin time's predictive value.

    Science.gov (United States)

    Le Guyader, Maïlys; Kaabar, Mohammed; Lemaire, Pierre; Pineau Vincent, Fabienne

    2015-01-01

    Dabigatran etexilate (Pradaxa®) is a new oral anticoagulant, competitive inhibitor, selective, fast, direct and reversible of thrombin. Dabigatran has an impact on a large panel of used coagulation tests. There is no relationship between thrombin time's lengthening and anti-IIa activity. This study defines thrombin time's predictive value, when its time is normal. The result of negative value is 97,6%. 255 patients were studied between January 2013 and July 2014. Thrombin time and anti-IIa activity were dosed for each patient. This study can be an assistant for therapeutic decision for laboratories without specialized test. PMID:26489812

  2. Fluxes, moduli fixing and MSSM-like vacua in Type IIA String Theory

    CERN Document Server

    Camara, P G

    2006-01-01

    We review some of the features of Type IIA compactifications in the presence of fluxes. In particular, the case of $T^6/(\\Omega (-1)^{F_L} \\sigma)$ orientifolds with RR, NS and metric fluxes is considered. This has revealed to possess remarkable properties such as vacua with all the closed string moduli stabilized, null or negative contributions to the RR tadpoles or supersymmetry on the branes enforced by the closed string background. In this way, Type IIA compactifications with non trivial fluxes seem to constitute a new window into the building of semi-realistic models in String Theory.

  3. Value of urinary topoisomerase-IIA cell-free DNA for diagnosis of bladder cancer

    OpenAIRE

    Kim, Ye-Hwan; Yan, Chunri; Lee, Il-Seok; Piao, Xuan-Mei; Byun, Young Joon; Jeong, Pildu; Kim, Won Tae; Yun, Seok-Joong; Kim, Wun-Jae

    2016-01-01

    Purpose Topoisomerase-II alpha (TopoIIA ), a DNA gyrase isoform that plays an important role in the cell cycle, is present in normal tissues and various human cancers, and can show altered expression in both. The aim of the current study was to examine the value of urinary TopoIIA cell-free DNA as a noninvasive diagnosis of bladder cancer (BC). Materials and Methods Two patient cohorts were examined. Cohort 1 (73 BC patients and seven controls) provided bladder tissue samples, whereas cohort ...

  4. Type-IIA flux compactifications and Script N = 4 gauged supergravities

    Science.gov (United States)

    Dall'Agata, Gianguido; Villadoro, Giovanni; Zwirner, Fabio

    2009-08-01

    We establish the precise correspondence between Type-IIA flux compactifications preserving an exact or spontaneously broken Script N = 4 supersymmetry in four dimensions, and gaugings of their effective Script N = 4 supergravities. We exhibit the explicit map between fluxes and Bianchi identities in the higher-dimensional theory and generalized structure constants and Jacobi identities in the reduced theory, also detailing the origin of gauge groups embedded at angles in the duality group. We present AdS4 solutions of the massive Type-IIA theory with spontaneous breaking to Script N = 1, at small string coupling and large volume, and discuss their dual CFT3.

  5. Effect of yeast with bacteriocin from rumen bacteria on laying performance, blood biochemistry, faecal microbiota and egg quality of laying hens.

    Science.gov (United States)

    Wang, H T; Shih, W Y; Chen, S W; Wang, S Y

    2015-12-01

    The purpose of this study was to evaluate the effect of yeast with bacteriocin from Ruminococcus albus 7 (albusin B) on physiological state and production performance of laying hens. One hundred and twenty 26-week-old Single Comb White Leghorn (Hyline) laying hens were assigned into five groups including: (i) control group, (ii) yeast control (YC), (iii) 0.125% yeast with bacteriocin (0.125B), (iv) 0.25% yeast with bacteriocin (0.25B) and (v) 0.5% yeast with bacteriocin (0.5B). All supplements were added to the experimental diets of the hens from 26 to 46 weeks of age. Samples were collected every 4 weeks. Blood samples were collected from the wing vein for blood biochemical parameters assay, and faecal samples were collected by swab for the microbiota test. The egg production performance was recorded daily, and fresh eggs were collected for quality test. The blood biochemical assay results indicated that the addition of yeast with bacteriocin decreased the AST (aspartate aminotransferase) activity and it also affects the lactate concentration in laying hen blood. The result of egg quality indicated that yeast with bacteriocin supplementation had no effect on the mass of yolk and the strength of eggshell, but it had positive effect on the laying performance under hot environment. Low concentration bacteriocin (0.125B) supplementation could decrease total yolk cholesterol. The faecal microbiota result indicated that the supplementation of bacteriocin increased the lactobacilli counts. The yeast with bacteriocin supplementation significantly decreased the clostridia counts under hot environment condition, especially in hens receiving 0.25B. Combining the data from clinic chemistry, faecal microbiota, egg production and egg quality, the 0.25B supplementation may result in the best physiological parameter and egg production performance of laying hen. PMID:25404002

  6. Bacteriocin production by Lactobacillus pentosus ST712BZ isolated from boza Bacteriocina produzida por Lactobacillus pentosus ST712BZ isolad de boza

    OpenAIRE

    Todorov, Svetoslav D.; Leon M. T. Dicks

    2007-01-01

    Bacteriocin ST712BZ (14.0kDa in size) inhibits the growth of Lactobacillus casei,Escherichia coli, Pseudomonas aeruginosa,Enterococcus faecalis, Klebsiella pneumoniae and Lactobacillus curvatus. Growth of strain ST712BZ in BHI, M17, soy milk and molasses was similar to growth in MRS, with optimal bacteriocin production (12800AU/mL) recorded in MRS after 24h. The same level of bacteriocin production (12800AU/mL) was recorded in MRS broth with an initial pH of 6.5, 6.0 and 5.5. However, MRS bro...

  7. Increased expression and activity of group IIA and X secretory phospholipase A2 in peritumoral versus central colon carcinoma tissue

    DEFF Research Database (Denmark)

    Tribler, Line; Jensen, Lotte T; Jørgensen, Kent;

    2007-01-01

    Secretory phospholipase A2 (sPLA2) type IIA and X was analyzed in tumors from 22 patients with colon adenocarcinomas in order to determine the involvement and activity of sPLA2 in colon cancer. Evaluation of immunoreactive sPLA2 IIA by Western blotting showed a significantly higher level in the...... periphery of the tumors, compared to central tumor regions. Increased levels of sPLA2 IIA protein correlated with a two-fold increase in sPLA2 enzymatic activity in the peripheral regions compared to central regions. Nineteen out of 22 tumors showed high levels of sPLA2 IIA, whereas 7 out of the 22 tumors...... showed sPLA2 type X. These data demonstrate that both sPLA2 type IIA and X are present in human colon cancer and suggest a role for sPLA2 in colon cancer tumor immunology and tumorigenesis....

  8. Increased expression and activity of group IIA and X secretory phospholipase A2 in peritumoral versus central colon carcinoma tissue

    DEFF Research Database (Denmark)

    Tribler, Line; Jensen, Lotte T; Jørgensen, Kent; Brünner, Nils; Gelb, Michael H; Nielsen, Hans Jørgen; Jensen, Simon S

    Secretory phospholipase A2 (sPLA2) type IIA and X was analyzed in tumors from 22 patients with colon adenocarcinomas in order to determine the involvement and activity of sPLA2 in colon cancer. Evaluation of immunoreactive sPLA2 IIA by Western blotting showed a significantly higher level in the...... periphery of the tumors, compared to central tumor regions. Increased levels of sPLA2 IIA protein correlated with a two-fold increase in sPLA2 enzymatic activity in the peripheral regions compared to central regions. Nineteen out of 22 tumors showed high levels of sPLA2 IIA, whereas 7 out of the 22 tumors...... showed sPLA2 type X. These data demonstrate that both sPLA2 type IIA and X are present in human colon cancer and suggest a role for sPLA2 in colon cancer tumor immunology and tumorigenesis....

  9. In vitro evaluation of bacteriocin-like inhibitory substances produced by lactic acid bacteria isolated during traditional Sicilian cheese making

    Directory of Open Access Journals (Sweden)

    Giusi Macaluso

    2016-02-01

    Full Text Available Bacteriocins are antimicrobial proteins produced by bacteria that inhibit the growth of other bacteria with a bactericidal or bacteriostatic mode of action. Many lactic acid bacteria (LAB produce a high diversity of different bacteriocins. Bacteriocinogenic LAB are generally recognised as safe (GRAS and useful to control the frequent development of pathogens and spoilage microorganisms. For this reason they are commonly used as starter cultures in food fermentations. In this study, the authors describe the results of a screening on 699 LAB isolated from wooden vat surfaces, raw milk and traditional Sicilian cheeses, for the production of bacteriocin-like inhibitory substances, by comparing two alternative methods. The antagonistic activity of LAB and its proteinaceous nature were evaluated using the spot-on-the-lawn and the well-diffusion assay (WDA and the sensitivity to proteolytic (proteinase K, protease B and trypsin, amylolytic (α-amylase and lipolytic (lipase enzymes. The indicator strains used were: Listeria monocytogenes, Staphylococcus aureus, Escherichia coli, Salmonella enteritidis. A total of 223 strains (belonging to the species Enterococcus spp., Lactobacillus spp., Pediococcus spp., Streptococcus spp., Leuconostoc spp. and Lactococcus lactis were found to inhibit the growth of Listeria monocytogenes by using the spot-on-the-lawn method; only 37 of these were confirmed by using the WDA. The direct addition of bacteriocin-producing cultures into dairy products can be a more practical and economic option for the improvement of the safety and quality of the final product.

  10. Potential use of Bacillus thuringiensis bacteriocins to control antibiotic-resistant bacteria associated with mastitis in dairy goats.

    Science.gov (United States)

    Gutiérrez-Chávez, A J; Martínez-Ortega, E A; Valencia-Posadas, M; León-Galván, M F; de la Fuente-Salcido, N M; Bideshi, D K; Barboza-Corona, J E

    2016-01-01

    Mastitis caused by microbial infections in dairy goats reduces milk yield, modifies milk composition, and potentially contributes to morbidity in herds and consumers of dairy products. Microorganisms associated with mastitis in dairy goats are commonly controlled with antibiotics, but it is known that continued use of these chemical agents promotes antibiotic resistance among bacterial populations. Recently, it has been shown that bacteriocins of Bacillus thuringiensis inhibit growth of food-borne pathogens and also bacteria associated with bovine mastitis. However, there is no report on their ability to inhibit microorganisms linked to mastitis in dairy goats. In this study, using 16S rDNA and ITS regions of rDNA, we identified nine bacterial isolates and an encapsulated yeast associated with mastitis in dairy goats. Enterococcus durans, Brevibacillus sp., and Staphylococcus epidermidis 2 were resistant to, respectively, 75, ~67, ~42, and ~42 % of the antibiotics screened. In addition, 60 % of the bacterial isolates were resistant to penicillin, ampicillin, vancomycin, and dicloxacillin. Importantly, 60 % of the isolates were inhibited by the bacteriocins, but S. epidermidis 1, Enterobacter sp., Escherichia vulneris, and Cryptococcus neoformans were not susceptible to these antimicrobial peptides. Using Brevibacillus sp. and Staphylococcus chromogenes as indicator bacteria, we show that peptides of ~10 kDa that correspond to the molecular mass of bacteriocins used in this study are responsible for the inhibitory activity. Our results demonstrate that multiple antibiotic-resistant bacteria associated with subclinical mastitis in dairy goats from Guanajuato, Mexico, are susceptible to bacteriocins produced by B. thuringiensis. PMID:26022411

  11. PRODUCTION OF BACTERIOCIN EC2 AND ITS INTERFERENCE IN THE GROWTH OF SALMONELLA TYPHI IN A MILK MATRIX

    Directory of Open Access Journals (Sweden)

    Yuri de Jesus Lopes de Abreu

    2013-08-01

    Full Text Available Bacterial interference can occur through various mechanisms, including the production of peroxides, acids, ammonia, bacteriolytic enzymes or bacteriocins. The strain Escherichia coli EC2 produces the antimicrobial substance (AMS EC2, able to inhibit different strains of Gram-negative bacteria isolated from food, as E. coli and Salmonella sp. The activity of AMS EC2 was lost after treatment with proteolytic enzymes, indicating the presence of an active proteinaceous compound, suggesting that it is a bacteriocin. The substance, renamed bacteriocin EC2, has its better production when the producer strain is grown on Casoy medium, at 37ºC and pH 6.0, without NaCl addition, but it is also able to be produced in milk. When co-cultivated in UHT milk with the producer strain E. coli EC2, the growth of the indicator strain Salmonella Typhi is totally inhibited within the first 4 hours of incubation, suggesting a potential application of bacteriocin EC2 in the control of Salmonella sp. e.g. in foods.

  12. Bacteriocin- producing strain of Enterococcus faecium EK 13 with probiotic character and its application in the digestive tract of rabbits

    Czech Academy of Sciences Publication Activity Database

    Lauková, A.; Strompfová, V.; Skřivanová, V.; Volek, Z.; Jindřichová, E.; Marounek, Milan

    2006-01-01

    Roč. 61, č. 6 (2006), s. 779-782. ISSN 0006-3088. [ Probiotic Conference /2./. Košice, 15.09.2006-19.09.2006] Grant ostatní: VEGA 2/5139/25 Institutional research plan: CEZ:AV0Z50450515 Keywords : probiotic * bacteriocin * enterocin Subject RIV: GH - Livestock Nutrition Impact factor: 0.213, year: 2006

  13. Antimicrobial activities of bacteriocins E50-52 and B602 against MRSA and other nosocomial infections

    Science.gov (United States)

    Our objective was to determine the antimicrobial activities of previously published bacteriocins E50-52 and B602 against methicillin resistant Staphylococcus aureus (MRSA) and other prominent nosocomial bacterial infections. methods: Several Russian hospitals were enlisted into the study from 2003 ...

  14. CHARACTERISTICS OF BACTERIOCIN BA28 PRODUCED BY Pediococcus acidilactici BA28

    Directory of Open Access Journals (Sweden)

    Kaur Baljinder

    2013-01-01

    Full Text Available Peptic ulcers are produced by an imbalance between gastro-duodenal mucosal defense mechanisms and damaging forces of gastric acid and pepsin, combined with superimposed injury from environmental or immunologic agents. Most common symptoms of peptic ulcer disease are abdominal discomfort, gnawing ache, occurs 2 to 3 hours after meal, other symptoms includes weight loss, poor appetite, bloating, nausea, vomiting etc. Some time duodenal wall perforates; bleeding due to the ulcer breaks blood vessels and obstructs the path of food trying to leave the stomach. Various studies have shown the association of Helicobacter pylori with peptic ulcers. Probiotic lactic acid bacteria are proposed to cure peptic ulcers by reducing colonization of H. pylori with stomach wall and by eradicating already established infection. A bacteriocin producing probiotic strain of P. acidilactici BA28 was evaluated for its antimicrobial activity against a number of Gram-positive and Gram-negative pathogens. Bacteriocin BA28 was partially purificated and characterized following in vitro assays. Preliminary investigations against H. plyori have suggested its effectiveness against peptic ulcer disease and therefore could be exploited to develop novel therapeutics.

  15. Autohydrolysed Tilapia nilotica Fish Viscera as a Peptone Source in Bacteriocin Production.

    Science.gov (United States)

    Deraz, Sahar F; El-Fawal, Gomaa F; Abd-Ellatif, Sawsan A; Khalil, Ashraf A

    2011-06-01

    Fish processing generates large amounts of solid and liquid wastes. Many different by-products have been produced from fish processing wastes. Studies on solubilization of Bolti fish (Tilapia nilotica) viscera by endogenous enzymes at different pHs are described. Hydrolysis reactions were conducted with freshly thawed viscera utilizing an initial temperature gradient and terminated at various time points by heat inactivation of the enzymes. Various peptones obtained from hydrolysed visceral homogenates of Bolti fish residues showed their suitability for promoting the growth of lactic acid bacteria (mainly Lactobacillus sake Lb 706), microorganisms with particularly complex nutritional requirements especially peptidic sources. The assay of several treatments with L. sakei Lb 706, producer of the bacteriocin sakacin A, demonstrated that optimum conditions for biomass and bacteriocin production only imply a brief autohydrolysis at room temperature. The results showed that the Bolti fish hydrolysates gave remarkable results to those found in costly commercial media, specifically recommended for culturing and large-scale production of lactic acid bacteria. PMID:22654160

  16. SCREENING OF LACTIC ACID BACTERIA FROM SUDANESE FERMENTED FOODS FOR BACTERIOCIN PRODUCTION

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    Yasmeen Y. A. Elyas

    2015-04-01

    Full Text Available Forty isolates of lactic acid bacteria (LAB were isolated from different types of fermented foods consumed in Sudan. Phenotypic tests revealed that all isolates were homofermentative LAB. Twenty-four isolates produced inhibitory substances primarily active against Staphylococcus aureus ATCC 2818 and Escherichia coli ATCC 29522. The inhibitory activity of 88% of enterococci and 58% of lactobacilli was recorded from meat isolates, whereas all activity of pediococcal isolates came from fermented milk isolates. The cell-free cultures of 18 isolates exhibiting inhibitory activity was chosen for further investigation such as sensitivity to proteolytic enzyme (pepsin, effect of heat treatment (60°C for 60min, 100°C for 20min and 121°C for 15min and effect of pH ( pH 2.0, pH 6.5, and pH 9.0. The inhibitory activity was eliminated upon treatment with pepsin. The bacteriocin-like substances lost their activity after heating at all temperatures used and at alkaline pH (9.0, whereas they were active at acidic pH (2.0. The antimicrobial activity of bacteriocin-like substances produced by the isolated LAB could prevent spoilage and/or pathogenic microorganism in Sudanese fermented food. Further study should be related with species identification of the producer strains and with the purification and characterization of these becteriocin-like substances in order to explore them in food industry.

  17. Effect of sodium chloride on growth and bacteriocin production by Lactobacillus amylovorus DCE 471.

    Science.gov (United States)

    Neysens, Patricia; Messens, Winy; De Vuyst, Luc

    2003-11-15

    A kinetic investigation of the effect of sodium chloride on cell growth of Lactobacillus amylovorus DCE 471 and amylovorin L471 production was carried out through in vitro experiments using a temperature and pH prevailing during sourdough fermentations. Sodium chloride interfered both with cell growth and bacteriocin production. Biomass formation and amylovorin L471 production decreased in the presence of increasing salt concentrations. Maximum bacteriocin activities were observed after the addition of 10 g l(-1) of NaCl, while the maximum specific growth rate reached an optimum at 5 g l(-1) of NaCl. High salt concentrations (20-40 g l(-1)) resulted in biphasic fermentation profiles. Based on these results, incorporation of 5-10 g l(-1) of sodium chloride in the water phase of type II sourdough preparations might be beneficial to enhance bacterial growth and amylovorin L471 production, and so contribute to the competitiveness of the strain in a sourdough environment. PMID:14527783

  18. Sugars relevant for sourdough fermentation stimulate growth of and bacteriocin production by Lactobacillus amylovorus DCE 471.

    Science.gov (United States)

    Leroy, Frédéric; De Winter, Tom; Adriany, Tom; Neysens, Patricia; De Vuyst, Luc

    2006-11-01

    The effects of sugars relevant for sourdough fermentation (i.e. glucose, fructose, maltose, and sucrose) on the kinetics of the bacteriocin-producing Lactobacillus amylovorus DCE 471 strain were assessed. The sugars were applied solely or in combination in a sourdough simulation medium during batch fermentations at temperature and pH conditions encountered during the production of type II sourdoughs. When growing on a single energy source, glucose was preferentially consumed by L. amylovorus DCE 471, followed by maltose and fructose. The strain was unable to grow on sucrose. In glucose-containing mixtures, glucose was always consumed most rapidly by L. amylovorus DCE 471 and seemed to steer its growth during the early growth phase, mainly because of the delaying effect on maltose consumption. Maltose consumption started only when low glucose levels were reached. In all cases, fructose was used as an energy source and not as a terminal electron acceptor, since no acetic acid or mannitol were produced. Increased bacteriocin titres were observed with binary or ternary sugar combinations compared to single energy sources. Thus, the diversity of the energy source seemed to stimulate the production of amylovorin L. Cell growth of and production of amylovorin L by L. amylovorus DCE 471 paralleled for all sugar combinations tested. PMID:16950530

  19. Genotypic and Phylogenic Analysis of Lactobacilli Producing Bacteriocin Isolated from Traditional Dairy Products and Food

    Directory of Open Access Journals (Sweden)

    Frazaneh Tafvizi

    2012-09-01

    Full Text Available Background & Objective: Lactic acid bacteria (LAB are a group of Gram-positive, non-spore forming, cocci or rod shaped, catalase negative organisms, considered as Generally Recognized as Safe (GRAS organisms. These bacteria are used for thousands of years for production of fermented foods because of their ability to produce desirable changes in taste, flavor and texture. Different antimicrobial molecules such as bacteriocins produced by these bacteria that can inhibit food pathogens, so enhancing the shelf life and improving the safety of food products. Because of important role of LAB to improving the human health, molecular identification and phylogenic analysis of these bacteria based on 16S rRNA sequencing play the critical role in investigation of local sources of LAB in Iran. Materials & Methods: 5 isolates were selected from 20 isolates for molecular identification. These strains produced the high level of bacteriocin. Total genomic DNA was extracted by lysosyme extraction protocol. PCR-mediated amplification was carried out by degenerate primers. Sequencing was performed after purification of PCR product. Results: Isolates were deposited as novel strains of Lactobacillus casei and Entrococcus facium in GenBank. Conclusion: Because of high potential of local probiotic bacteria in Iran, these strains may be useful and could be used in the food industry.

  20. Tanshinone IIA Prevents Leu27IGF-II-Induced Cardiomyocyte Hypertrophy Mediated by Estrogen Receptor and Subsequent Akt Activation.

    Science.gov (United States)

    Weng, Yueh-Shan; Wang, Hsueh-Fang; Pai, Pei-Ying; Jong, Gwo-Ping; Lai, Chao-Hung; Chung, Li-Chin; Hsieh, Dennis Jine-Yuan; HsuanDay, Cecilia; Kuo, Wei-Wen; Huang, Chih-Yang

    2015-01-01

    IGF-IIR plays important roles as a key regulator in myocardial pathological hypertrophy and apoptosis, which subsequently lead to heart failure. Salvia miltiorrhiza Bunge (Danshen) is a traditional Chinese medicinal herb used to treat cardiovascular diseases. Tanshinone IIA is an active compound in Danshen and is structurally similar to 17[Formula: see text]-estradiol (E[Formula: see text]. However, whether tanshinone IIA improves cardiomyocyte survival in pathological hypertrophy through estrogen receptor (ER) regulation remains unclear. This study investigates the role of ER signaling in mediating the protective effects of tanshinone IIA on IGF-IIR-induced myocardial hypertrophy. Leu27IGF-II (IGF-II analog) was shown in this study to specifically activate IGF-IIR expression and ICI 182,780 (ICI), an ER antagonist used to investigate tanshinone IIA estrogenic activity. We demonstrated that tanshinone IIA significantly enhanced Akt phosphorylation through ER activation to inhibit Leu27IGF-II-induced calcineurin expression and subsequent NFATc3 nuclear translocation to suppress myocardial hypertrophy. Tanshinone IIA reduced the cell size and suppressed ANP and BNP, inhibiting antihypertrophic effects induced by Leu27IGF-II. The cardioprotective properties of tanshinone IIA that inhibit Leu27IGF-II-induced cell hypertrophy and promote cell survival were reversed by ICI. Furthermore, ICI significantly reduced phospho-Akt, Ly294002 (PI3K inhibitor), and PI3K siRNA significantly reduced the tanshinone IIA-induced protective effect. The above results suggest that tanshinone IIA inhibited cardiomyocyte hypertrophy, which was mediated through ER, by activating the PI3K/Akt pathway and inhibiting Leu27IGF-II-induced calcineurin and NFATC3. Tanshinone IIA exerted strong estrogenic activity and therefore represented a novel selective ER modulator that inhibits IGF-IIR signaling to block cardiac hypertrophy. PMID:26621443

  1. Characterization of Xanthomonas spp. strains by bacteriocins Caracterização de isolados de Xanthomonas spp. por bacterocinas

    Directory of Open Access Journals (Sweden)

    Marcel Bonini

    2007-03-01

    Full Text Available Twenty-five strains of Xanthomonas axonopodis pv. citri and 14 strains of Xanthomonas spp. were tested for bacteriocin production. X. axonopodis pv. passiflorae strains were sensitive to the bacteriocins produced by the 25 X. axonopodis pv. citri strains evaluated in this study while strains of X. axonopodis pv. manihotis and X. campestris pv. campestris showed variable sensitivity. Only five of the 25 X. axonopodis pv. citri strains were not inhibited by the bacteriocins produced by the two X. axonopodis pv. passiflorae strains. The bacteriocins produced by the Xanthomonas axonopodis pv. citri (FDC-806 and X. axonopodis pv. passiflorae (Mar-2850 A strains were thermolabile, resistant to lysozyme and sensitive to DNAse. The bacteriocin produced by X. axonopodis pv. passiflorae was resistant to the action of proteinase K, trypsin and RNAse while the bacteriocin produced by X. axonopodis pv. citri was sensitive to these enzymes. The bacteriocins produced by X. axonopodis pv. passiflorae and X. axonopodis pv. citri were called passifloricin and citricin, respectively.Vinte e cinco isolados de Xanthomonas axonopodis pv. citri e 14 isolados de Xanthomonas spp. foram comparados a fim de verificar a capacidade de produção de bacteriocina e a sua sensibilidade. Isolados de X. axonopodis pv. passiflorae foram sensíveis às bacteriocinas produzidas por 25 isolados de X. axonopodis pv. citri avaliados e os isolados de X. axonopodis pv. manihotis e X. campestris pv. campestris apresentaram sensibilidade variável. Dos 25 isolados de X. axonopodis pv. citri apenas cinco não foram inibidos pelas bacteriocinas produzidas por dois isolados de X. axonopodis pv. passiflorae. As bacteriocinas produzidas pelos isolados de X. axonopodis pv. citri (FDC-806 e de X. axonopodis pv. passiflorae (Mar-2850 A foram termolábeis e resistentes à lisozima e sensíveis a DNAse. A bacteriocina produzida pelo isolado de X. axonopodis pv. passiflorae foi resistente à a

  2. Exploration and conservation of bacterial genetic resources as bacteriocin producing inhibitory microorganisms to pathogen bacteria in livestock

    Directory of Open Access Journals (Sweden)

    Chotiah S

    2013-06-01

    Full Text Available Exploration and conservation of microorganisms producing bacteriocin was done as the primary study towards the collection of potential bacteria and its application in improving livestock health condition and inhibit food borne pathogens. Diferent kinds of samples such as beef cattle rectal swab, rumen fluids, cow’s milk, chicken gut content, goat’s milk were collected at Bogor cattle slaughter houses, poultry slaughter houses, dairy cattle and goat farms. A total of 452 bacterial isolates consisted of 73 Gram negative bacteria and 379 Gram positive bacteria were isolated from samples collected and screened for bacteriocin activity. Determination of bacteriocin activity with bioassay using agar spot tests were carried out on liquid and semisolid medium assessing 8 kins of indicators of pathogenic bacteria and food borne pathogens. A total of 51 bacteriocin producing strains were collected and some of the strains had high inhibitory zone such as Lactobacillus casei SS14C (26 mm, Enterobacter cloacae SRUT (24mm, Enterococcus faecalis SK39 (21mm and Bifidobacterium dentium SS14T (20mm respectively, to Salmonella typhimurium BCC B0046/ATCC 13311, E. coli O157 hemolytic BCC B2717, Listeria monocytogenes BCC B2767/ATCC 7764 and Escherichia coli VTEC O157 BCC B2687. Evaluation after conservation ex situ to all bacterocin producing strain at 5oC for 1 year in freeze drying ampoules in vacuum and dry condition revealed the decreasing viability starting from log 0.8 CFU/ml for Lactococcus and Leuconostoc to log 2.2. CFU/ml for Streptococcus. Result of the study showed that the bacteriocin producing strains obtained were offered a potential resource for preventing disease of livestock and food borne diseases.

  3. Sodium Tanshinone IIA Sulfonate Attenuates Scopolamine-Induced Cognitive Dysfunctions via Improving Cholinergic System.

    Science.gov (United States)

    Xu, Qing-Qing; Xu, Yi-Jun; Yang, Cong; Tang, Ying; Li, Lin; Cai, Hao-Bin; Hou, Bo-Nan; Chen, Hui-Fang; Wang, Qi; Shi, Xu-Guang; Zhang, Shi-Jie

    2016-01-01

    Sodium Tanshinone IIA sulfonate (STS) is a derivative of Tanshinone IIA (Tan IIA). Tan IIA has been reported to possess neuroprotective effects against Alzheimer's disease (AD). However, whether STS possesses effect on AD remains unclear. This study aims to estimate whether STS could protect against scopolamine- (SCOP-) induced learning and memory deficit in Kunming mice. Morris water maze results showed that oral administration of STS (10 mg/kg and 20 mg/kg) and Donepezil shortened escape latency, increased crossing times of the original position of the platform, and increased the time spent in the target quadrant. STS decreased the activity of acetylcholinesterase (AChE) and increased the activity of choline acetyltransferase (ChAT) in the hippocampus and cortex of SCOP-treated mice. Oxidative stress results showed that STS increased the activity of superoxide dismutase (SOD) and decreased the levels of malondialdehyde (MDA) and reactive oxygen species (ROS) in hippocampus and cortex. In addition, western blot was carried out to detect the expression of apoptosis related proteins (Bcl-2, Bax, and Caspase-3). STS upregulated the protein expression of Bcl-2 and downregulated the proteins expression of Bax and Caspase-3. These results indicated that STS might become a promising therapeutic candidate for attenuating AD-like pathological dysfunction. PMID:27556046

  4. Supersymmetric double-well matrix model as two-dimensional type IIA superstring on RR background

    International Nuclear Information System (INIS)

    In the previous paper, the authors pointed out correspondence of a supersymmetric double-well matrix model with two-dimensional type IIA superstring theory on a nontrivial Ramond-Ramond background from the viewpoint of symmetries and spectrum. In this paper we further investigate the correspondence from dynamical aspects by comparing scattering amplitudes in the matrix model and those in the type IIA theory. In the latter, cocycle factors are introduced to vertex operators in order to reproduce correct transformation laws and target-space statistics. By a perturbative treatment of the Ramond-Ramond background as insertions of the corresponding vertex operators, various IIA amplitudes are explicitly computed including quantitatively precise numerical factors. We show that several kinds of amplitudes in both sides indeed have exactly the same dependence on parameters of the theory. Moreover, we have a number of relations among coefficients which connect quantities in the type IIA theory and those in the matrix model. Consistency of the relations convinces us of the validity of the correspondence

  5. Consistent ${\\cal N}=8$ truncation of massive IIA on $S^6$

    CERN Document Server

    Guarino, Adolfo

    2015-01-01

    Massive type IIA supergravity is shown to admit a consistent truncation on the six-sphere to maximal supergravity in four dimensions with a dyonic ISO(7) gauging. We obtain the complete, non-linear embedding of all the $D=4$ fields into the IIA metric and form potentials, and show its consistency. We first rewrite the IIA theory in an $\\textrm{SO}(1,3) \\times \\textrm{SL}(7)$--covariant way. Then, we employ an ${\\cal N}=8$ SL(7)--covariant restriction of the $D=4$ tensor hierarchy in order to find the full embedding. The redundant $D=4$ degrees of freedom introduced by the tensor hierarchy can be eliminated by writing the embedding in terms of the field strengths and exploiting the restricted duality hierarchy. In particular, closed expressions for the Freund-Rubin term are found using this technique which reveal a pattern valid for other truncations. Finally, we show that the present ${\\cal N}=8$ truncation of massive IIA on $S^6$ and the ${\\cal N}=2$ truncation obtained when $S^6$ is equipped with its nearly...

  6. Expression of Dihydropyridine and Ryanodine Receptors in Type IIA Fibers of Rat Skeletal Muscle

    International Nuclear Information System (INIS)

    In this study, the fiber type specificity of dihydropyridine receptors (DHPRs) and ryanodine receptors (RyRs) in different rat limb muscles was investigated. Western blot and histochemical analyses provided for the first time evidence that the expression of both receptors correlates to a specific myosin heavy chain (MHC) composition. We observed a significant (p=0.01) correlation between DHP as well as Ry receptor density and the expression of MHC IIa (correlation factor r=0.674 and r=0.645, respectively) in one slow-twitch, postural muscle (m. soleus), one mixed, fast-twitch muscle (m. gastrocnemius) and two fast-twitch muscles (m. rectus femoris, m. extensor digitorum longus). The highest DHP and Ry receptor density was found in the white part of m. rectus femoris (0.058±0.0060 and 0.057±0.0158 ODu, respectively). As expected, the highest relative percentage of MHC IIa was also found in the white part of m. rectus femoris (70.0±7.77%). Furthermore, histochemical experiments revealed that the IIA fibers stained most strongly for the fluorophore-conjugated receptor blockers. Our data clearly suggest that the expression of DHPRs and RyRs follows a fiber type-specific pattern, indicating an important role for these proteins in the maintenance of an effective Ca2+ cycle in the fast contracting fiber type IIA

  7. The N=4 effective action of type IIA supergravity compactified on SU(2)-structure manifolds

    CERN Document Server

    Danckaert, Thomas; Martínez-Pedrera, Danny; Spanjaard, Bastiaan; Triendl, Hagen

    2011-01-01

    We study compactifications of type IIA supergravity on six-dimensional manifolds with SU(2) structure and compute the low-energy effective action in terms of the non-trivial intrinsic torsion. The consistency with gauged N=4 supergravity is established and the gauge group is determined. Depending on the structure of the intrinsic torsion, antisymmetric tensor fields can become massive.

  8. Purification and characterization of a phospholipase A2-IIA from common stingray (Dasyatis pastinaca) intestine.

    Science.gov (United States)

    Ben Bacha, Abir; Daihan, Sooad K; Moubayed, Nadine M S; Mejdoub, Hafedh

    2013-06-01

    A phospholipase A2 belonging to IIA group secretory PLA2 was isolated and purified to homogeneity from the intestine of common stingray (Dasyatis pastinaca) using acidic treatment (pH 1.5) and ammonium sulphate precipitation methods combined with single-column ion-exchange chromatography. The purified enzyme was found to be a glycosylated monomeric protein with a molecular mass of about 14 kDa. The stingray sPLA2-IIA had optimum activity at 45 degrees C, unlike known mammalian PLA2-IIAs, which show optimum activity at 37 degrees C. The purified enzyme exhibited a specific activity of 290 U/mg at optimal conditions (pH 9.5 and 45 degrees C) in the presence of 6 mM NaDC and 8 mM CaCl2 with egg yolk as substrate. The NH2-terminal sequence of the enzyme and some protein fragments obtained from its tryptic digestion were also determined. All sequences obtained were similar to those of sPLA2-IIA. The enzyme also showed good stability in the presence of organic solvents, acidic and alkaline pH media and high temperature conditions. Thus, the purified enzyme exhibited a number of unique and promising properties, making it a potential possible candidate for future applications in the treatment of phospholipid-rich industrial effluents and synthesis of useful preparations for the food production and processing industry. PMID:23898481

  9. 30 CFR 57.22603 - Blasting from the surface (II-A mines).

    Science.gov (United States)

    2010-07-01

    ... shall be approved by MSHA under the applicable requirements of 30 CFR parts 18 through 36. Vehicles... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Blasting from the surface (II-A mines). 57... MINES Safety Standards for Methane in Metal and Nonmetal Mines Explosives § 57.22603 Blasting from...

  10. [Liquisolid technique for enhancement of dissolution prosperities of tanshinone II(A)].

    Science.gov (United States)

    Liu, Xiao-qian; Meng, Qing-ju; Xu, Xue-lin; Zhao, Jie; Yang, Hua; Yi, Hong

    2015-12-01

    The technique of liquisolid compress is a new technique developed in 1990s, which was considered to be the most promising technique to improve the dissolution of water-insoluble drugs. In this article, tanshinone II(A) and the extracts of the ester-solubility fractions were chosen as the model drugs to evaluate the effects of the liquisolid technique for enhancement of dissolution properties of tanshinone II(A). Several liquisolid tablets (LS) formulations containing different dosage of drugs and various liquid vehicle were pre-pared and for all the formulations, microcrystalline cellulose and silica were chosen as the carrier and coating materials to evaluate their flow properties, such as angle of repose, Carr's compressibility index and Hausner's ratio. The interaction between drug and excipients in prepared LS compacts were studied by differential scanning calorimetry(DSC) and X-ray powder diffraction (XRPD). The dissolution curves of tanshinone II(A) from liquisolid compacts were investigated to determine the technique's effect in improving the dissolution of tanshinone II(A) and its impacting factors. According to the results, the dissolution increased with the rise in the dissolution of the liquid-phase solvent. The R-value and drug dosage can significantly affect the drug release, but with less impact on active fractions. This indicated that liquisolid technique is a promising alternative for improvement of dissolution property of water-soluble drugs, and can make a synergistic effect with other ester-soluble constituents and bettern improve the release of tanshinone II(A). Therefore, the technique of liquisolid compress will have a better development prospect in traditional Chinese medicines. PMID:27245032

  11. Radiation-induced myosin IIA expression stimulates collagen type I matrix reorganization

    International Nuclear Information System (INIS)

    Background and purpose: Extracellular matrix (ECM) reorganization critically contributes to breast cancer (BC) progression and radiotherapy response. We investigated the molecular background and functional consequences of collagen type I (col-I) reorganization by irradiated breast cancer cells (BCC). Materials and methods: Radiation-induced (RI) col-I reorganization was evaluated for MCF-7/6, MCF-7/AZ, T47D and SK-BR-3 BCC. Phase-contrast microscopy and a stressed matrix contraction assay were used for visualization and quantification of col-I reorganization. Cell–matrix interactions were assessed by the inhibition of β1 integrin (neutralizing antibody ‘P5D2’) or focal adhesion kinase (FAK; GSK22560098 small molecule kinase inhibitor). The role of the actomyosin cytoskeleton was explored by western blotting analysis of myosin II expression and activity; and by gene silencing of myosin IIA and pharmacological inhibition of the actomyosin system (blebbistatin, cytochalasin D). BCC death was evaluated by propidium iodide staining. Results: We observed a radiation dose-dependent increase of col-I reorganization by BCC. β1 Integrin/FAK-mediated cell–matrix interactions are essential for RI col-I reorganization. Irradiated BCC are characterized by increased myosin IIA expression and myosin IIA-dependent col-I reorganization. Moreover, RI col-I reorganization by BCC is associated with decreased BCC death, as suggested by pharmacological targeting of the β1 integrin/FAK/myosin IIA pathway. Conclusions: Our data indicate the role of myosin IIA in col-I reorganization by irradiated BCC and reciprocal BCC death

  12. Detection and Biochemical Characterization of Microorganisms in Milk and Cocoa powder samples by FTIR and subsequent production of Bacteriocin from Lactobacillus

    Directory of Open Access Journals (Sweden)

    Ramalingam C

    2013-03-01

    Full Text Available Cocoa and milk powder samples were taken from a confectionery and tested for presence of microbes (harmful and pathogenic.Biochemical characterization of isolated microbes was carried out for confirmation. Lactobacillus was isolated from milk powder. When a culture of Lactobacillus sp. was inoculated into milk and incubated at room temperature, it multiplies and converts lactose to lactic acid. Fourier transform infrared spectroscopy was used to study the variation of functional group peaks in milk by the action of Lactobacillus sp. The spectral changes were also observed. Our main aim of this project is the production of bacteriocin from isolated lactobacillus species; it showed broad range of antibacterial activity against some food borne pathogens like staphyloccus, Ecoli, streptococcus, Enterococcus etc. The bacteriocin is purified by ammonium sulfate precipitate and dialysis. Biochemically it was pure protein moiety. Maximum bacteriocin concentration was found after dialysis. Project revealed the possibility of using bacteriocin as food preservative.

  13. Molecular Occurrence of Enterocin A Gene among Enterococcus faecium Strains Isolated from Gastro-Intestinal Tract and Antimicrobial Effect of this Bacteriocin Against Clinical Pathogens

    Directory of Open Access Journals (Sweden)

    Mitra Salehi

    2014-06-01

    Materials and Methods: In this study occurrence of class II enterocin structural gene (enterocin A in a target of 42 Enterococcus faecium strains, isolated from gastrointestinal tract of animal have been surveyed. E. faecium identification and occurrence of enterocin A gene was performed by PCR method. Cell-free neutralized supernatant of gene positive strains was used to test bacteriocin production and antimicrobial spectrum of supernatant was assayed by wall diffusion method on the gram-positive and negative indicators bacteriaResults: Based on our results, 73.8% of isolated strains had enterocin A gene that they inhibited growth of indicator bacteria such as clinical strain of Pseudomonas aeruginosa, Salmonella enteric PTCC1709, Listeria monocytogenes, Bacillus cereus and Bacillus subtilis.Conclusions: Studied enterocins have growth inhibitory spectrum on Gram-positive and Gram-negative bacteria especially against pathogenic bacteria in the gastrointestinal tract. Therefore, these strains have the potential to explore and use as, alternative antimicrobial compound and bio-preservatives in food or feed or as probiotics.

  14. Structure-Function Analysis of the Two-Peptide Bacteriocin Plantaricin EF.

    Science.gov (United States)

    Ekblad, Bie; Kyriakou, Panagiota K; Oppegård, Camilla; Nissen-Meyer, Jon; Kaznessis, Yiannis N; Kristiansen, Per Eugen

    2016-09-13

    Plantaricin EF is a two-peptide bacteriocin that depends on the complementary action of two different peptides (PlnE and PlnF) to function. The structures of the individual peptides have previously been analyzed by nuclear magnetic resonance spectroscopy ( Fimland, N. et al. ( 2008 ) , Biochim. Biophys. Acta 1784 , 1711 - 1719 ), but the bacteriocin structure and how the two peptides interact have not been determined. All two-peptide bacteriocins identified so far contain GxxxG motifs. These motifs, together with GxxxG-like motifs, are known to mediate helix-helix interactions in membrane proteins. We have mutated all GxxxG and GxxxG-like motifs in PlnE and PlnF in order to determine if any of these motifs are important for antimicrobial activity and thus possibly for interactions between PlnE and PlnF. Moreover, the aromatic amino acids Tyr and Trp in PlnE and PlnF were substituted, and four fusion polypeptides were constructed in order to investigate the relative orientation of PlnE and PlnF in target cell membranes. The results obtained with the fusion polypeptides indicate that PlnE and PlnF interact in an antiparallel manner and that the C-terminus of PlnE and N-terminus of PlnF are on the outer part of target cell membranes and the N-terminus of PlnE and C-terminus of PlnF are on the inner part. The preference for an aromatic residue at position 6 in PlnE suggests a positioning of this residue in or near the membrane interface on the cells inside. Mutations in the GxxxG motifs indicate that the G5xxxG9 motif in PlnE and the S26xxxG30 motif in PlnF are involved in helix-helix interactions. Atomistic molecular dynamics simulation of a structural model consistent with the results confirmed the stability of the structure and its orientation in membranes. The simulation approved the anticipated interactions and revealed additional interactions that further increase the stability of the proposed structure. PMID:27538436

  15. sPLA2-IIA Augments Oxidized LDL-Induced MCP-1 Expression in Vitro Through Activation of Akt

    Directory of Open Access Journals (Sweden)

    Yongjun Guo

    2015-10-01

    Full Text Available Background/Aims: Group IIA secretory phospholipase A2 (sPLA2-IIA has an important role in atherosclerosis. In this study, we explored whether sPLA2-IIA overexpression could promote atherosclerosis in normal environment alone or with other inflammatory factors. Methods: Human aortic smooth muscle cells (HASMCs were transduced with Lv-GFP-sPLA2-IIA, a plasmid containing sPLA2-IIA coupled with green fluorescent protein (GFP. Cells were incubated in the presence or absence of oxidized low-density lipoprotein (LDL, sPLA2 inhibitor LY315920 or PI3K/Akt inhibitor LY294002. The mRNA expression and protein secretion of monocyte chemoattractant protein-1 (MCP-1 were assessed by quantitative real-time polymerase chain reaction (QRT-PCR and enzyme-linked immunosorbent assay (ELISA, respectively. Phosphorylation of Akt was examined by western blotting. Results: Lv-GFP-sPLA2-IIA-transduced HASMCs remained fluorescent during 72 h of the study period with infection ratio of around 80%. The mRNA expression and protein secretion of MCP-1was not altered in groups of HASMCs, Lv-GFP transduced and Lv-GFP-sPLA2-IIA-transduced HASMCs (p>0.05, but was significantly increased in the presence of oxidized LDL especially in Lv-GFP-sPLA2-IIA transduction group (ppConclusions: Overexpression of sPLA2-IIA does not alter MCP-1 level at baseline, but could enhance the atherogenic effect of oxidized LDL in HASMCs, at least partly due to activation of Akt. These findings may provide a strategy for treatment of inflammatory cardiovascular diseases.

  16. The Curing Agent Sodium Nitrite, Used in the Production of Fermented Sausages, Is Less Inhibiting to the Bacteriocin-Producing Meat Starter Culture Lactobacillus curvatus LTH 1174 under Anaerobic Conditions

    OpenAIRE

    Verluyten, Jurgen; Messens, Winy; De Vuyst, Luc

    2003-01-01

    Curvacin A is a listericidal bacteriocin produced by Lactobacillus curvatus LTH 1174, a strain isolated from fermented sausage. The response of this strain to an added curing agent (sodium nitrite) in terms of cell growth and bacteriocin production was investigated in vitro by laboratory fermentations with modified MRS broth. The strain was highly sensitive to nitrite; even a concentration of 10 ppm of curing agent inhibited its growth and both volumetric and specific bacteriocin production. ...

  17. Heritability assessment of cartilage metabolism. A twin study on circulating procollagen IIA N-terminal propeptide (PIIANP)

    DEFF Research Database (Denmark)

    Munk, H L; Svendsen, A J; Hjelmborg, J V B;

    2014-01-01

    OBJECTIVE: The aim of this investigation was to estimate the heritability of circulating collagen IIA N-terminal propeptide (PIIANP) by studying mono- and dizygotic healthy twin pairs at different age and both genders. DESIGN: 598 monozygotic (MZ) and dizygotic (DZ) twin individuals aged 18...... the collagen IIA synthesis as assessed by the collagen IIA N-terminal propeptide in serum is attributable to genetic effectors while individual and shared environment account for 24% and 31% respectively. The heritability does not differ between genders or according to age....

  18. Medical and Personal Care Applications of Bacteriocins Produced by Lactic Acid Bacteria

    Science.gov (United States)

    Dicks, L. M. T.; Heunis, T. D. J.; van Staden, D. A.; Brand, A.; Noll, K. Sutyak; Chikindas, M. L.

    The frequent use of antibiotics has led to a crisis in the antibiotic ­resistance of pathogens associated with humans and animals. Antibiotic resistance and the emergence of multiresistant bacterial pathogens have led to the investigation of alternative antimicrobial agents to treat and prevent infections in both humans and animals. Research on antimicrobial peptides, with a special interest on bacteriocins of lactic acid bacteria, is entering a new era with novel applications other than food preservation. Many scientists are now focusing on the application of these peptides in medicinal and personal care products. However, it is difficult to assess the success of such ventures due to the dearth of information that has been published and the lack of clinical trials.

  19. Production of bacteriocin-like substances by lactic acid bacteria isolated from regional ovine cheese

    Directory of Open Access Journals (Sweden)

    Cássia Regina Nespolo

    2010-12-01

    Full Text Available Lactic acid bacteria (LAB were isolated from ovine milk and cheeses manufactured in the South Region of Brazil. Among 112 bacterial isolates investigated, 59 were chosen through a screening for LAB. Among these 59 strains of LAB, 21% showed antimicrobial, proteolytic and lipolytic activities. Based on this screening, Lactobacillus plantarum LCN 17 and Lactobacillus rhamnosus LCN 43 were selected and tested for the production of bacteriocin-like substances (BLS. The BLS produced by both isolates showed antimicrobial activity against Listeria monocytogenes, whereas that produced by L. plantarum LCN 17 presented higher stability to different temperature, pH and enzyme treatments. These strains present potential for production of BLS, and for use as starter cultures.

  20. Colostrum of healthy Slovenian mothers: microbiota composition and bacteriocin gene prevalence.

    Science.gov (United States)

    Obermajer, Tanja; Lipoglavšek, Luka; Tompa, Gorazd; Treven, Primož; Lorbeg, Petra Mohar; Matijašić, Bojana Bogovič; Rogelj, Irena

    2014-01-01

    Microbial communities inhabiting the breast milk microenvironment are essential in supporting mammary gland health in lactating women and in providing gut-colonizing bacterial 'inoculum' for their infants' gastro-intestinal development. Bacterial DNA was extracted from colostrum samples of 45 healthy Slovenian mothers. Characteristics of the communities in the samples were assessed by polymerase chain reaction (PCR) coupled with denaturing gradient gel electrophoresis (DGGE) and by quantitative real-time PCR (qPCR). PCR screening for the prevalence of bacteriocin genes was performed on DNA of culturable and total colostrum bacteria. DGGE profiling revealed the presence of Staphylococcus and Gemella in most of the samples and exposed 4 clusters based on the abundance of 3 bands: Staphylococcus epidermidis/Gemella, Streptococcus oralis/pneumonia and Streptococcus salivarius. Bacilli represented the largest proportion of the communities. High prevalence in samples at relatively low quantities was confirmed by qPCR for enterobacteria (100%), Clostridia (95.6%), Bacteroides-Prevotella group (62.2%) and bifidobacteria (53.3%). Bacterial quantities (genome equivalents ml-1) varied greatly among the samples; Staphylococcus epidermidis and staphylococci varied in the range of 4 logs, streptococci and all bacteria varied in the range of 2 logs, and other researched groups varied in the range of 1 log. The quantity of most bacterial groups was correlated with the amount of all bacteria. The majority of the genus Staphylococcus was represented by the species Staphylococcus epidermidis (on average 61%), and their abundances were linearly correlated. Determinants of salivaricin A, salivaricin B, streptin and cytolysin were found in single samples. This work provides knowledge on the colostrum microbial community composition of healthy lactating Slovenian mothers and reports bacteriocin gene prevalence. PMID:25919457

  1. Colostrum of healthy Slovenian mothers: microbiota composition and bacteriocin gene prevalence.

    Directory of Open Access Journals (Sweden)

    Tanja Obermajer

    Full Text Available Microbial communities inhabiting the breast milk microenvironment are essential in supporting mammary gland health in lactating women and in providing gut-colonizing bacterial 'inoculum' for their infants' gastro-intestinal development. Bacterial DNA was extracted from colostrum samples of 45 healthy Slovenian mothers. Characteristics of the communities in the samples were assessed by polymerase chain reaction (PCR coupled with denaturing gradient gel electrophoresis (DGGE and by quantitative real-time PCR (qPCR. PCR screening for the prevalence of bacteriocin genes was performed on DNA of culturable and total colostrum bacteria. DGGE profiling revealed the presence of Staphylococcus and Gemella in most of the samples and exposed 4 clusters based on the abundance of 3 bands: Staphylococcus epidermidis/Gemella, Streptococcus oralis/pneumonia and Streptococcus salivarius. Bacilli represented the largest proportion of the communities. High prevalence in samples at relatively low quantities was confirmed by qPCR for enterobacteria (100%, Clostridia (95.6%, Bacteroides-Prevotella group (62.2% and bifidobacteria (53.3%. Bacterial quantities (genome equivalents ml-1 varied greatly among the samples; Staphylococcus epidermidis and staphylococci varied in the range of 4 logs, streptococci and all bacteria varied in the range of 2 logs, and other researched groups varied in the range of 1 log. The quantity of most bacterial groups was correlated with the amount of all bacteria. The majority of the genus Staphylococcus was represented by the species Staphylococcus epidermidis (on average 61%, and their abundances were linearly correlated. Determinants of salivaricin A, salivaricin B, streptin and cytolysin were found in single samples. This work provides knowledge on the colostrum microbial community composition of healthy lactating Slovenian mothers and reports bacteriocin gene prevalence.

  2. Platelets release mitochondria serving as substrate for bactericidal group IIA-secreted phospholipase A2 to promote inflammation

    OpenAIRE

    Boudreau, Luc H.; Duchez, Anne-Claire; Cloutier, Nathalie; Soulet, Denis; Martin, Nicolas; Bollinger, James; Paré, Alexandre; Rousseau, Matthieu; Naika, Gajendra S.; Lévesque, Tania; Laflamme, Cynthia; Marcoux, Geneviève; Lambeau, Gérard; Farndale, Richard W.; Pouliot, Marc

    2014-01-01

    When activated and in platelet storage bags, platelets release respiratory-competent mitochondria, a recognized damage-associated molecular pattern.Mitochondria, descendant of Rickettsia prowazekii, serve as substrate for bactericidal sPLA2-IIA to promote inflammation.

  3. Rational sphere valued supercocycles in M-theory and type IIA string theory

    CERN Document Server

    Fiorenza, Domenico; Schreiber, Urs

    2016-01-01

    We show that supercocycles on super $L_\\infty$-algebras capture, at the rational level, the twisted cohomological charge structure of the fields of M-theory and of type IIA string theory. We show that rational 4-sphere-valued supercocycles for M-branes in M-theory descend to supercocycles in type IIA string theory to yield the Ramond-Ramond fields predicted by the rational image of twisted K-theory, with the twist given by the B-field. In particular, we derive the M2/M5 $\\leftrightarrow$ F1/Dp/NS5 correspondence via dimensional reduction of sphere-valued $L_\\infty$ supercocycles in rational homotopy theory.

  4. Deformed N = 8 supergravity from IIA strings and its Chern-Simons duals

    Energy Technology Data Exchange (ETDEWEB)

    Guarino, Adolfo [Nikhef Theory Group, Amsterdam (Netherlands); Jafferis, Daniel L. [Center for the Fundamental Laws of Nature, Harvard University, Cambridge, MA (United States); Varela, Oscar [Center for the Fundamental Laws of Nature, Harvard University, Cambridge, MA (United States); Centre de Physique Theorique, Ecole Polytechnique, CNRS UMR 7644, Palaiseau (France)

    2016-04-15

    Do electric/magnetic deformations of N = 8 supergravity enjoy a string/M-theory origin, or are they just a fourdimensional artefact? We address this question for the gauging of a group closely related to SO(8): its contraction ISO(7). We argue that the deformed ISO(7) supergravity arises from consistent truncation of massive IIA supergravity on S{sup 6}, and its electric/magnetic deformation parameter descends directly from the Romans mass. The critical points of the supergravity uplift to AdS{sub 4} massive type IIA vacua and the corresponding CFT{sub 3} duals are identified as super-Chern-Simons-matter theories with gauge group SU(N) and level k given also by the Romans mass. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  5. A Global View on The Search for de-Sitter Vacua in (type IIA) String Theory

    CERN Document Server

    Chen, Xingang; Sumitomo, Yoske; Tye, S -H Henry

    2011-01-01

    The search for classically stable Type IIA de-Sitter vacua typically starts with an ansatz that gives Anti-de-Sitter supersymmetric vacua and then raises the cosmological constant by modifying the compactification. As one raises the cosmological constant, the couplings typically destabilize the classically stable vacuum, so the probability that this approach will lead to a classically stable de-Sitter vacuum is Gaussianly suppressed. This implies that classically stable de-Sitter vacua in string theory (at least in the Type IIA region), especially those with relatively high cosmological constants, are very rare. The probability that a typical de-Sitter extremum is classically stable (i.e., tachyon-free) is argued to be Gaussianly suppressed as a function of the number of moduli.

  6. AdS4 solutions of massive IIA from dyonic ISO(7) supergravity

    Science.gov (United States)

    Varela, Oscar

    2016-03-01

    Explicit formulae are given for the consistent truncation of massive type IIA supergravity on the six-sphere to the SU(3)-invariant sector of D = 4 {N}=8 supergravity with dyonic ISO(7) gauging. These formulae are then used to construct AdS4 solutions of massive type IIA via uplift on S 6 of the critical points of the D = 4 supergravity with at least SU(3) symmetry. We find a new {N}=1 solution with SU(3) symmetry, a new non-supersymmetric solution with SO(6) symmetry, and recover previously known solutions. We quantise the fluxes, calculate the gravitational free energies of the solutions and discuss the stability of the non-supersymmetric ones. Among these, a (previously known) G2-invariant solution is found to be stable.

  7. IIA String Theory on Calabi-Yau Fourfolds with Background Fluxes

    CERN Document Server

    Gukov, S G; Gukov, Sergei; Haack, Michael

    2002-01-01

    Looking for string vacua with fixed moduli, we study compactifications of type IIA string theory on Calabi-Yau fourfolds in the presence of generic Ramond-Ramond fields. We explicitly derive the (super)potential induced by Ramond-Ramond fluxes performing a Kaluza-Klein reduction of the ten-dimensional effective action. This can be conveniently achieved in a formulation of the massive type IIA supergravity where all Ramond-Ramond fields appear in a democratic way. The result agrees with the general formula for the superpotential written in terms of calibrations. We further notice that for generic Ramond-Ramond fluxes all geometric moduli are stabilized and one finds non-supersymmetric vacua at positive values of the scalar potential.

  8. A naturally chimeric type IIA topoisomerase in Aquifex aeolicus highlights an evolutionary path for the emergence of functional paralogs

    OpenAIRE

    Tretter, Elsa M.; Lerman, Jeffrey C.; Berger, James M.

    2010-01-01

    Bacteria frequently possess two type IIA DNA topoisomerases, gyrase and topo IV, which maintain chromosome topology by variously supercoiling, relaxing, and disentangling DNA. DNA recognition and functional output is thought to be controlled by the C-terminal domain (CTD) of the topoisomerase DNA binding subunit (GyrA/ParC). The deeply rooted organism Aquifex aeolicus encodes one type IIA topoisomerase conflictingly categorized as either DNA gyrase or topo IV. To resolve this enzyme’s catalyt...

  9. 30 CFR 57.22608 - Secondary blasting (I-A, II-A, and V-A mines).

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Secondary blasting (I-A, II-A, and V-A mines... blasting (I-A, II-A, and V-A mines). Prior to secondary blasting, tests for methane shall be made in the mine atmosphere at blast sites by a competent person. Secondary blasting shall not be done when...

  10. Cell-wall determinants of the bactericidal action of group IIA phospholipase A2 against Gram-positive bacteria

    OpenAIRE

    Foreman-Wykert, Amy K.; Weinrauch, Yvette; Elsbach, Peter; Weiss, Jerrold

    1999-01-01

    We have shown previously that a group IIA phospholipase A2 (PLA2) is responsible for the potent bactericidal activity of inflammatory fluids against many Gram-positive bacteria. To exert its antibacterial activity, this PLA2 must first bind and traverse the bacterial cell wall to produce the extensive degradation of membrane phospholipids (PL) required for bacterial killing. In this study, we have examined the properties of the cell-wall that may determine the potency of group IIA PLA2 action...

  11. Autologous Myoblast Transplantation for Oculopharyngeal Muscular Dystrophy: a Phase I/Iia Clinical Study

    OpenAIRE

    Périé, Sophie; Trollet, Capucine; Mouly, Vincent; Vanneaux, Valérie; Mamchaoui, Kamel; Bouazza, Belaïd; Marolleau, Jean Pierre; Laforêt, Pascal; Chapon, Françoise; Eymard, Bruno; Butler-Browne, Gillian; Larghero, Jérome; St Guily, Jean Lacau

    2013-01-01

    Oculopharyngeal muscular dystrophy (OPMD) is a late-onset autosomal dominant genetic disease mainly characterized by ptosis and dysphagia. We conducted a phase I/IIa clinical study (ClinicalTrials.gov NCT00773227) using autologous myoblast transplantation following myotomy in adult OPMD patients. This study included 12 patients with clinical diagnosis of OPMD, indication for cricopharyngeal myotomy, and confirmed genetic diagnosis. The feasibility and safety end points of both autologous myob...

  12. The Vascular Effects of Sodium Tanshinone IIA Sulphonate in Rodent and Human Pregnancy

    OpenAIRE

    Morton, Jude S.; Andersson, Irene J.; Cheung, Po-Yin; Baker, Philip; Davidge, Sandra T.

    2015-01-01

    Danshen, in particular its derivative tanshinone IIA (TS), is a promising compound in the treatment of cardiovascular diseases and has been used for many years in traditional Chinese medicine. Although many actions of TS have been researched, its vasodilator effects in pregnancy remain unknown. There have been a few studies that have shown the ability of TS to reduce blood pressure in women with hypertensive pregnancies; however, there are no studies which have examined the vascular effects o...

  13. 10D massive type IIA supergravities as the uplift of parabolic M2-brane torus bundles

    Energy Technology Data Exchange (ETDEWEB)

    Garcia del Moral, Maria Pilar [Universidad de Antofagasta (Chile). Dept. de Fisica; Restuccia, Alvaro [Universidad de Antofagasta (Chile). Dept. de Fisica; Universidad Simon Bolivar, Caracas (Venezuela, Bolivarian Republic of). Dept. de Fisica

    2016-04-15

    We remark that the two 10D massive deformations of the N = 2 maximal type IIA supergravity (Romans and HLW supergravity) are associated to the low energy limit of the uplift to 10D of M2-brane torus bundles with parabolic monodromy linearly and non-linearly realized respectively. Romans supergravity corresponds to M2-brane compactified on a twice-punctured torus bundle. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  14. A Global View on The Search for de-Sitter Vacua in (type IIA) String Theory

    OpenAIRE

    Chen, Xingang; Shiu, Gary; Sumitomo, Yoske; Tye, S.-H. Henry

    2011-01-01

    The search for classically stable Type IIA de-Sitter vacua typically starts with an ansatz that gives Anti-de-Sitter supersymmetric vacua and then raises the cosmological constant by modifying the compactification. As one raises the cosmological constant, the couplings typically destabilize the classically stable vacuum, so the probability that this approach will lead to a classically stable de-Sitter vacuum is Gaussianly suppressed. This suggests that classically stable de-Sitter vacua in st...

  15. Perfrin, a novel bacteriocin associated with netB positive Clostridium perfringens strains from broilers with necrotic enteritis.

    Science.gov (United States)

    Timbermont, Leen; De Smet, Lina; Van Nieuwerburgh, Filip; Parreira, Valeria R; Van Driessche, Gonzalez; Haesebrouck, Freddy; Ducatelle, Richard; Prescott, John; Deforce, Dieter; Devreese, Bart; Van Immerseel, Filip

    2014-01-01

    Necrotic enteritis in broiler chickens is associated with netB positive Clostridium perfringens type A strains. It is known that C. perfringens strains isolated from outbreaks of necrotic enteritis are more capable of secreting factors inhibiting growth of other C. perfringens strains than strains isolated from the gut of healthy chickens. This characteristic could lead to extensive and selective presence of a strain that contains the genetic make-up enabling to secrete toxins that cause gut lesions. This report describes the discovery, purification, characterization and recombinant expression of a novel bacteriocin, referred to as perfrin, produced by a necrotic enteritis-associated netB-positive C. perfringens strain. Perfrin is a 11.5 kDa C-terminal fragment of a 22.9 kDa protein and showed no sequence homology to any currently known bacteriocin. The 11.5 kDa fragment can be cloned into Escherichia coli, and expression yielded an active peptide. PCR detection of the gene showed its presence in 10 netB-positive C. perfringens strains of broiler origin, and not in other C. perfringens strains tested (isolated from broilers, cattle, sheep, pigs, and humans). Perfrin and NetB are not located on the same genetic element since NetB is plasmid-encoded and perfrin is not. The bacteriocin has bactericidal activity over a wide pH-range but is thermolabile and sensitive to proteolytic digestion (trypsin, proteinase K). C. perfringens bacteriocins, such as perfrin, can be considered as an additional factor involved in the pathogenesis of necrotic enteritis in broilers. PMID:24708344

  16. Exploration and conservation of bacterial genetic resources as bacteriocin producing inhibitory microorganisms to pathogen bacteria in livestock

    OpenAIRE

    2013-01-01

    Exploration and conservation of microorganisms producing bacteriocin was done as the primary study towards the collection of potential bacteria and its application in improving livestock health condition and inhibit food borne pathogens. Diferent kinds of samples such as beef cattle rectal swab, rumen fluids, cow’s milk, chicken gut content, goat’s milk were collected at Bogor cattle slaughter houses, poultry slaughter houses, dairy cattle and goat farms. A total of 452 bacterial isolates con...

  17. Isolation, biochemical characterization, and cloning of a bacteriocin from the poultry-associated Staphylococcus aureus strain CH-91

    OpenAIRE

    Wladyka, Benedykt; Wielebska, Katarzyna; Wloka, Marcin; Bochenska, Oliwia; Dubin, Grzegorz; Dubin, Adam; Mak, Pawel

    2012-01-01

    Staphylococcus aureus strain CH-91, isolated from a broiler chicken with atopic dermatitis, has a highly proteolytic phenotype that is correlated with the disease. We describe the isolation and biochemical and molecular characterization of the AI-type lantibiotic BacCH91 from S. aureus CH-91 culture medium. The bacteriocin was purified using a three-stage procedure comprising precipitation with ammonium sulfate, extraction with organic solvents, and reversed-phase HPLC. The BacCH91 peptide is...

  18. Focal cortical dysplasia type IIa and IIb: MRI aspects in 118 cases proven by histopathology

    Energy Technology Data Exchange (ETDEWEB)

    Colombo, Nadia; Citterio, Alberto [Ospedale Ca Granda Niguarda, Department of Neuroradiology, Milano (Italy); Tassi, Laura; Mai, Roberto; Sartori, Ivana; Cardinale, Francesco; Lo Russo, Giorgio [Ospedale Niguarda, Claudio Munari Epilepsy Surgery Center, Milano (Italy); Deleo, Francesco; Spreafico, Roberto [IRCCS Foundation Neurological Institute ' ' C. Besta' ' , Department of Epilepsy Clinic and Experimental Neurophysiology, Milano (Italy); Bramerio, Manuela [Ospedale Niguarda, Department of Pathology, Milano (Italy)

    2012-10-15

    This study aims to review the magnetic resonance imaging (MRI) aspects of a large series of patients with focal cortical dysplasia type II (FCD II) and attempt to identify distinctive features in the two histopathological subtypes IIa and IIb. We retrospectively reviewed the MRI scans of 118 patients with histological proven FCD IIa (n = 37) or IIb (n = 81) who were surgically treated for intractable epilepsy. MRI was abnormal in 93 patients (79 %) and unremarkable in 25 (21 %). A dysplastic lesion was identified in 90 cases (97 %) and classified as FCD II in 83 and FCD non-II in seven cases. In three cases, the MRI diagnosis was other than FCD. There was a significant association between the presence of cortical thickening (p = 0.002) and the ''transmantle sign'' (p < 0.001) and a correct MRI diagnosis of FCD II. MRI positivity was more frequent in the patients with FCD IIb than in those with FCD IIa (91 % vs. 51 %), and the detection rate of FCD II was also better in the patients with type IIb (88 % vs. 32 %). The transmantle sign was significantly more frequent in the IIb subgroup (p = 0.003). The rates of abnormal MRI results and correct MRI diagnoses of FCD II were significantly higher in the IIb subgroup. Although other MRI stigmata may contribute to the diagnosis, the only significant correlation was between the transmantle sign and FCD IIb. (orig.)

  19. Focal cortical dysplasia type IIa and IIb: MRI aspects in 118 cases proven by histopathology

    International Nuclear Information System (INIS)

    This study aims to review the magnetic resonance imaging (MRI) aspects of a large series of patients with focal cortical dysplasia type II (FCD II) and attempt to identify distinctive features in the two histopathological subtypes IIa and IIb. We retrospectively reviewed the MRI scans of 118 patients with histological proven FCD IIa (n = 37) or IIb (n = 81) who were surgically treated for intractable epilepsy. MRI was abnormal in 93 patients (79 %) and unremarkable in 25 (21 %). A dysplastic lesion was identified in 90 cases (97 %) and classified as FCD II in 83 and FCD non-II in seven cases. In three cases, the MRI diagnosis was other than FCD. There was a significant association between the presence of cortical thickening (p = 0.002) and the ''transmantle sign'' (p < 0.001) and a correct MRI diagnosis of FCD II. MRI positivity was more frequent in the patients with FCD IIb than in those with FCD IIa (91 % vs. 51 %), and the detection rate of FCD II was also better in the patients with type IIb (88 % vs. 32 %). The transmantle sign was significantly more frequent in the IIb subgroup (p = 0.003). The rates of abnormal MRI results and correct MRI diagnoses of FCD II were significantly higher in the IIb subgroup. Although other MRI stigmata may contribute to the diagnosis, the only significant correlation was between the transmantle sign and FCD IIb. (orig.)

  20. 4d N=2 superconformal linear quivers with type IIA duals

    CERN Document Server

    Aharony, Ofer; Berkooz, Micha

    2012-01-01

    We discuss the gravity duals of 4d N=2 superconformal field theories (SCFTs) arising from the low-energy limit of brane configurations of D4-branes stretched between and intersecting NS5-branes and D6-branes. This gives rise to a product of SU(N_i) groups, with bi-fundamental matter between adjacent groups, and extra fundamental hypermultiplets. The most general configuration in 11d (or type IIA) supergravity that is dual to a 4d N=2 SCFT (when the dual of this SCFT is a weakly curved background) was written down by Gaiotto and Maldacena, but finding it explicitly involves solving a complicated Toda equation. This equation simplifies only when the solution can be reduced to type IIA supergravity, so we ask for which SCFTs of this type is there a type IIA dual that is weakly coupled and weakly curved (away from NS5-branes and D6-branes). We find that such solutions (a special case of which was analyzed by Reid-Edwards and Stefanski) exist when there is a large number of gauge groups, with large ranks, and with...

  1. Anti-bactericidal properties of stingray Dasyatis pastinaca groups V, IIA, and IB phospholipases A2: a comparative study.

    Science.gov (United States)

    Bacha, Abir Ben

    2014-10-01

    Group IIA secreted phospholipase A2 (group IIA sPLA2) is known to display potent Gram-positive bactericidal activity in vitro and in vivo. We have analyzed the bactericidal activity of the full set of native stingray and dromedary groups V, IIA, and IB sPLA2s on several Gram-positive and Gram-negative strains. The rank order potency among both marine and mammal sPLA2s against Gram-positive bacteria is group IIA > V > IB, whereas Gram-negative bacteria exhibited a much higher resistance. There is a synergic action of the sPLA2 with lysozyme when added to the bacteria culture prior to sPLA2.The bactericidal efficiency of groups V and IIA sPLA2s was shown to be dependent upon the presence of calcium ions and to a less extent Mg(2+) ions and then a correlation could be made to its hydrolytic activity of membrane phospholipids. Importantly, we showed that stingray and dromedary groups V, IIA, and IB sPLA2s present no cytotoxicity after their incubation with MDA-MB-231cells. stingray groups V and IIA sPLA2s, like mammal ones, may be considered as future therapeutic agents against bacterial infections. PMID:25119545

  2. Potential of bacteriocin-producing lactic acid bacteria for safety improvements of traditional Thai fermented meat and human health.

    Science.gov (United States)

    Swetwiwathana, Adisorn; Visessanguan, Wonnop

    2015-11-01

    Lactic acid bacteria (LAB) are very important in converting of agricultural products into safe, delicious and shelf stable foods for human consumption. The preservative activity of LAB in foods is mainly attributed to the production of anti-microbial metabolites such as organic acids and bacteriocins which enables them to grow and control the growth of pathogens and spoilage microorganisms. Besides ensuring safety, bacteriocin-producing LAB with their probiotic potentials could also be emerging as a means to develop functional meat products with desirable health benefits. Nevertheless, to be qualified as a candidate probiotic culture, other prerequisite probiotic properties of bacteriocin-producing LAB have to be assessed according to regulatory guidelines for probiotics. Nham is an indigenous fermented sausage of Thailand that has gained popularity and acceptance among Thais. Since Nham is made from raw meat and is usually consumed without cooking, risks due to undesirable microorganisms such as Salmonella spp., Staphylococcus aureus, and Listeria monocytogenes, are frequently observed. With an ultimate goal to produce safer and healthier product, our research attempts on the development of a variety of new Nham products are discussed. PMID:26100576

  3. Screening of Bacteriocin-producing Lactic Acid Bacteria%产细菌素乳酸菌的筛选

    Institute of Scientific and Technical Information of China (English)

    胡欣洁; 刘云; 邓清云

    2012-01-01

    [Objective]To develop a strain of high-efficient bacteriocin with broader antimicrobial spectrum as natural preservative. [ Method] With pickles and yoghurt as raw materials, the bacteria, which could inhibit the indicator bacteria, was screened from the test materials by using MRS selective medium, and whether the bacteria could produce bacteriocin or not was determined by the tests of excluding acid inhibition, hydrogen peroxide inhibition and protease sensitivity. [Result]The screened strain was identified to be lactic acid bacteria, the produced bacteriocin had inhibitive effect against gram-negative and gram-positive bacteria, and it was a strain of lactic acid bacteria with iroad spectrum and the ability of bacteriocin-producing. [Conclusion]The bacteriocin-producing lactic acid bacteria had important roles in inhibiting various pathogens and food decay.%[目的]开发出更加高效、抑菌谱更广、可做天然防腐剂的细菌素.[方法]以泡菜、酸奶为原料,利用MRS选择培养基从试材中筛选出能够抑制指示菌的细菌,通过排除酸抑制作用、过氧化氢抑制作用和蛋白酶敏感性试验证明该菌株是否产生有抑菌作用的细菌素.[结果]筛选得到的菌株经鉴定证明是乳酸菌,其产生的细菌素对革兰氏阴性菌和革兰氏阳性菌都有抑制作用,是一株产广谱细菌素的乳酸菌.[结论]筛选得出的乳酸菌细菌素在抑制各种病原菌和食品腐败等方面具有重要作用.

  4. Domain-induced activation of human phospholipase A2 type IIA: Local versus global lipid composition

    DEFF Research Database (Denmark)

    Leidy, C.; Linderoth, L.; Andresen, T.L.; Mouritsen, O.G.; Jørgensen, K.; Peters, Günther H.j.

    2006-01-01

    , we show that local enrichment of anionic lipids into fluid domains triggers PLA(2)-IIA activity. In addition, the compositional range of enzyme activity is shown to be related to the underlying lipid phase diagram. A comparison is done between PLA(2)-IIA and snake venom PLA(2), which in contrast to...... PLA(2)-IIA hydrolyzes both anionic and zwitterionic membranes. In general, this work shows that PLA(2)-IIA activation can be accomplished through local enrichment of anionic lipids into domains, indicating a mechanism for PLA(2)-IIA to target perturbed native membranes with low global anionic lipid...... contents. The results also show that the underlying lipid phase diagram, which determines the lipid composition at a local level, can be used to predict PLA(2)-IIA activity....

  5. Detection and preliminary characterization of a narrow spectrum bacteriocin produced by Lactobacillus pentosus K2N7 from Thai traditional fermented shrimp (Kung-Som

    Directory of Open Access Journals (Sweden)

    Nisit Watthanasakphuban

    2016-02-01

    Full Text Available A total of 48 lactic acid bacteria (LAB exhibited antagonistic activity against Lactobacillus sakei subsp. sakei JCM 1157 or Staphylococcus aureus DMST 8840. Only strain K2N7 was selected for characterization of bacteriocin activity. It was identified as Lactobacillus pentosus based on 16S rDNA analysis. The maximum bacteriocin production was detected in early stationary phase of growth. It was found to be sensitive to proteolytic enzymes (trypsin, proteinase K, pronase E and -chymotrypsin. The bacteriocin K2N7 was heat stable (2 h at 100ºC and retained activity over a wide pH range (2.0-12.0. Bacteriocin K2N7 has a narrow inhibitory spectrum restricted to genus Lactobacillus including Lactobacillus plantarum D6SM3, a bacterial strain known to cause overfermentation in Kung-Som. The peptide was purified by 60% ammonium sulphate precipitation followed by sequential cation exchange chromatography and hydrophobic interaction characteristic. The molecular mass of bacteriocin K2N7 (2.017 kDa was determined by matrix-assisted laser desorption/ionization time-offlight mass spectrometry analysis (MALDI-TOF MS.

  6. A ptsP deficiency in PGPR Pseudomonas fluorescens SF39a affects bacteriocin production and bacterial fitness in the wheat rhizosphere.

    Science.gov (United States)

    Godino, Agustina; Príncipe, Analía; Fischer, Sonia

    2016-04-01

    Pseudomonas fluorescens SF39a is a plant-growth-promoting bacterium isolated from wheat rhizosphere. In this report, we demonstrate that this native strain secretes bacteriocins that inhibit growth of phytopathogenic strains of the genera Pseudomonas and Xanthomonas. An S-type pyocin gene was detected in the genome of strain SF39a and named pys. A non-polar pys::Km mutant was constructed. The bacteriocin production was impaired in this mutant. To identify genes involved in bacteriocin regulation, random transposon mutagenesis was carried out. A miniTn5Km1 mutant, called P. fluorescens SF39a-451, showed strongly reduced bacteriocin production. This phenotype was caused by inactivation of the ptsP gene which encodes a phosphoenolpyruvate phosphotransferase (EI(Ntr)) of the nitrogen-related phosphotransferase system (PTS(Ntr)). In addition, this mutant showed a decrease in biofilm formation and protease production, and an increase in surface motility and pyoverdine production compared with the wild-type strain. Moreover, we investigated the ability of strain SF39a-451 to colonize the wheat rhizosphere under greenhouse conditions. Interestingly, the mutant was less competitive than the wild-type strain in the rhizosphere. To our knowledge, this study provides the first evidence of both the relevance of the ptsP gene in bacteriocin production and functional characterization of a pyocin S in P. fluorescens. PMID:26708985

  7. Partial Purification and Characterization of a Bacteriocin DT24 Produced by Probiotic Vaginal Lactobacillus brevis DT24 and Determination of its Anti-Uropathogenic Escherichia coli Potential.

    Science.gov (United States)

    Trivedi, Disha; Jena, Prasant Kumar; Patel, Jignesh Kumar; Seshadri, Sriram

    2013-06-01

    The emergence of antibiotic resistance has increased the interest for finding new antimicrobials in the past decade. Probiotic Lactic acid bacteria producing antimicrobial proteins like bacteriocin can be excellent agents for development as novel therapeutic agents and complement to conventional antibiotic therapy. Uropathogenic Escherichia coli, most causative agent of Urinary tract infection, has developed resistance to various antibiotics. In the present investigation, antibacterial substance like bacteriocin (Bacteriocin DT24) produced by probiotic Lactobacillus brevis DT24 from vaginal sample of healthy Indian woman was partially purified and characterized. It was efficiently working against various pathogens, that is, Uropathogenic E. coli, Enterococcus faecium, Enterococcus faecalis and Staphylococcus aureus. The antimicrobial peptide was relatively heat resistant and also active over a broad range of pH 2-10. It has been partially purified by ammonium sulfate precipitation and gel filtration chromatography and checked on reverse-phase high-performance liquid chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of bacteriocin DT24 was approximately 7-kDa protein. The peptide is inactivated by proteolytic enzymes, trypsin and lipase but not when treated with catalase, α-amylase and pepsin. It showed bacteriostatic mode of action against uropathogenic E. coli. Such characteristics indicate that this bacteriocin-producing probiotic may be a potential candidate for alternative agents to control urinary tract infections and other pathogens. PMID:26782739

  8. Nuclear Magnetic Resonance Solution Structures of Lacticin Q and Aureocin A53 Reveal a Structural Motif Conserved among Leaderless Bacteriocins with Broad-Spectrum Activity.

    Science.gov (United States)

    Acedo, Jeella Z; van Belkum, Marco J; Lohans, Christopher T; Towle, Kaitlyn M; Miskolzie, Mark; Vederas, John C

    2016-02-01

    Lacticin Q (LnqQ) and aureocin A53 (AucA) are leaderless bacteriocins from Lactococcus lactis QU5 and Staphylococcus aureus A53, respectively. These bacteriocins are characterized by the absence of an N-terminal leader sequence and are active against a broad range of Gram-positive bacteria. LnqQ and AucA consist of 53 and 51 amino acids, respectively, and have 47% identical sequences. In this study, their three-dimensional structures were elucidated using solution nuclear magnetic resonance and were shown to consist of four α-helices that assume a very similar compact, globular overall fold (root-mean-square deviation of 1.7 Å) with a highly cationic surface and a hydrophobic core. The structures of LnqQ and AucA resemble the shorter two-component leaderless bacteriocins, enterocins 7A and 7B, despite having low levels of sequence identity. Homology modeling revealed that the observed structural motif may be shared among leaderless bacteriocins with broad-spectrum activity against Gram-positive organisms. The elucidated structures of LnqQ and AucA also exhibit some resemblance to circular bacteriocins. Despite their similar overall fold, inhibition studies showed that LnqQ and AucA have different antimicrobial potency against the Gram-positive strains tested, suggesting that sequence disparities play a crucial role in their mechanisms of action. PMID:26771761

  9. Effects of Tanshinone IIA on the modulation of miR-33a and the SREBP-2/Pcsk9 signaling pathway in hyperlipidemic rats

    OpenAIRE

    Jia, Lianqun; Song, Nan; Yang, Guanlin; MA, YIXIN; LI, XUETAO; Lu, Ren; Cao, Huimin; Zhang, Ni; Zhu, Meilin; Wang, Junyan; Leng, Xue; Cao, Yuan; Du, Ying; Xu, Yue

    2016-01-01

    Tanshinone IIA is the active compound isolated from Salvia miltiorrhiza bunge, which is a traditional Chinese medicine known as Danshen. The aim of the present study was to assess the effect of Tanshinone IIA on the regulation of lipid metabolism in the livers of hyperlipidemic rats and the underlying molecular events. An in vivo model of hyperlipidemia was established in rats, with the animals receiving a daily dose of Tanshinone IIA. The serum lipid profiles were analyzed using an automatic...

  10. Stage IIA and IIB testicular seminoma treated post-orchiectomy with radiation therapy versus other approaches: a population-based analysis of 241 patients

    OpenAIRE

    Kamran A. Ahmed; Wilder, Richard B.

    2015-01-01

    Objectives To evaluate post-orchiectomy utilization of radiation therapy (RT) versus other management approaches in stage IIA and IIB testicular seminoma patients. Materials and Methods Two hundred and forty-one patients with stage IIA and IIB testicular seminoma were identified between 1988 and 2003 using the Surveillance, Epidemiology, and End Results (SEER) database. Results Median follow-up was 10 years. Patients with stage IIA disease underwent RT more frequently than those with stage II...

  11. The effect of bacteriocin-producing Lactobacillus plantarum strains on the intracellular pH of sessile and planktonic Listeria monocytongenes single cells

    DEFF Research Database (Denmark)

    Nielsen, Dennis Sandris; Cho, Gyu-Sung; Hanak, Alexander;

    2010-01-01

    , but still notable. L. plantarum PCS 20 left both strains of L. monocytogenes virtually unaffected when co-cultured on a solid surface. In liquid, both L. plantarum strains strongly affected the physiological state of L. monocytogenes EGDe as judged by pHi, whereas L. monocytogenes N53-1 was left......A wide range of lactic acid bacteria (LAB) produce bacteriocins mainly active against other closely related LAB, but some bacteriocins are also active against the food-borne pathogen Listeria monocytogenes. With the aim of increasing food safety it has thus been considered to utilise bacteriocins...... and/or bacteriocin-producing LAB as “natural” food preservatives in foods such as cheese, meat and ready-to-eat products. Some strains of Lactobacillus plantarum produce bacteriocins termed plantaricins. Using a single-cell based approach, the effect on the intracellular pH as a measure of the...

  12. Leuconostoc carnosum 4010 has the potential for use as a protective culture for vacuum-packed meats: culture isolation, bacteriocin identification, and meat application experiments

    DEFF Research Database (Denmark)

    Budde, B.B.; Hornbæk, T.; Jacobsen, T.; Barkholt, Vibeke; Koch, A.G.

    2003-01-01

    A new culture, Leuconostoc carnosum 4010, for biopreservation of vacuum-packed meats is described. The culture originated from bacteriocin-producing lactic acid bacteria (LAB) naturally present in vacuum-packed meat products. Approximately, 72,000 colonies were isolated from 48 different vacuum...... activity without producing any undesirable flavour components in meat products. For identification of the bacteriocins produced, partial purification was carried out by ammonium sulphate precipitation, dialysis, and cation exchange chromatography. SDS-PAGE analysis revealed two bands with inhibitory...... activity corresponding to molecular sizes of 4.6 and 5.3 kDa. N-terminal amino acid sequencing showed that Leuc. carnosum 4010 produced two bacteriocins highly similar or identical to leucocin A and leucocin C. Application experiments showed that the addition of 10(7) cfu/g Leuc. carnosum 4010 to a vacuum...

  13. Nisin, an apoptogenic bacteriocin and food preservative, attenuates HNSCC tumorigenesis via CHAC1

    International Nuclear Information System (INIS)

    Nisin, a bacteriocin and commonly used food preservative, may serve as a novel potential therapeutic for treating head and neck squamous cell carcinoma (HNSCC), as it induces preferential apoptosis, cell cycle arrest, and reduces cell proliferation in HNSCC cells, compared with primary keratinocytes. Nisin also reduces HNSCC tumorigenesis in vivo. Mechanistically, nisin exerts these effects on HNSCC, in part, through CHAC1, a proapoptotic cation transport regulator, and through a concomitant CHAC1-independent influx of extracellular calcium. In addition, although CHAC1 is known as an apoptotic mediator, its effects on cancer cell apoptosis have not been examined. Our studies are the first to report CHAC1's new role in promoting cancer cell apoptosis under nisin treatment. These data support the concept that nisin decreases HNSCC tumorigenesis in vitro and in vivo by inducing increased cell apoptosis and decreased cell proliferation; effects that are mediated by activation of CHAC1, increased calcium influxes, and induction of cell cycle arrest. These findings support the use of nisin as a potentially novel therapeutic for HNSCC, and as nisin is safe for human consumption and currently used in food preservation, its translation into a clinical setting may be facilitated

  14. Nisin, an apoptogenic bacteriocin and food preservative, attenuates HNSCC tumorigenesis via CHAC1.

    Science.gov (United States)

    Joo, Nam E; Ritchie, Kathryn; Kamarajan, Pachiyappan; Miao, Di; Kapila, Yvonne L

    2012-12-01

    Nisin, a bacteriocin and commonly used food preservative, may serve as a novel potential therapeutic for treating head and neck squamous cell carcinoma (HNSCC), as it induces preferential apoptosis, cell cycle arrest, and reduces cell proliferation in HNSCC cells, compared with primary keratinocytes. Nisin also reduces HNSCC tumorigenesis in vivo. Mechanistically, nisin exerts these effects on HNSCC, in part, through CHAC1, a proapoptotic cation transport regulator, and through a concomitant CHAC1-independent influx of extracellular calcium. In addition, although CHAC1 is known as an apoptotic mediator, its effects on cancer cell apoptosis have not been examined. Our studies are the first to report CHAC1's new role in promoting cancer cell apoptosis under nisin treatment. These data support the concept that nisin decreases HNSCC tumorigenesis in vitro and in vivo by inducing increased cell apoptosis and decreased cell proliferation; effects that are mediated by activation of CHAC1, increased calcium influxes, and induction of cell cycle arrest. These findings support the use of nisin as a potentially novel therapeutic for HNSCC, and as nisin is safe for human consumption and currently used in food preservation, its translation into a clinical setting may be facilitated. PMID:23342279

  15. Genetic features of circular bacteriocins produced by Gram-positive bacteria.

    Science.gov (United States)

    Maqueda, Mercedes; Sánchez-Hidalgo, Marina; Fernández, Matilde; Montalbán-López, Manuel; Valdivia, Eva; Martínez-Bueno, Manuel

    2008-01-01

    This review highlights the main genetic features of circular bacteriocins, which require the co-ordinated expression of several genetic determinants. In general terms, it has been demonstrated that the expression of such structural genes must be combined with the activity of proteins involved in maturation (cleavage/circularization) and secretion outside the cell via different transporter systems, as well as multifaceted immunity mechanisms essential to ensuring the bacteria's self-protection against such strong inhibitors. Several circular antibacterial peptides produced by Gram-positive bacteria have been described to date, including enterocin AS-48, from Enterococcus faecalis S-48 (the first one characterized), gassericin A, from Lactobacillus gasseri LA39, and a similar one, reutericin 6, from Lactobacillus reuteri LA6, butyrivibriocin AR10, from the ruminal anaerobe Butyrivibrio fibrisolvens AR10, uberolysin, from Streptococcus uberis, circularin A, from Clostridium beijerinckii ATCC 25752, and subtilosin A, from Bacillus subtilis. We summarize here the progress made in the understanding of their principal genetic features over the last few years, during which the functional roles of circular proteins with wide biological activity have become clearer. PMID:18034824

  16. The large mechanosensitive channel MscL determines bacterial susceptibility to the bacteriocin sublancin 168.

    Science.gov (United States)

    Kouwen, Thijs R H M; Trip, Erik N; Denham, Emma L; Sibbald, Mark J J B; Dubois, Jean-Yves F; van Dijl, Jan Maarten

    2009-11-01

    Bacillus subtilis strain 168 produces the extremely stable and broad-spectrum lantibiotic sublancin 168. Known sublancin 168-susceptible organisms include important pathogens, such as Staphylococcus aureus. Nevertheless, since its discovery, the mode of action of sublancin 168 has remained elusive. The present studies were, therefore, aimed at the identification of cellular determinants for bacterial susceptibility toward sublancin 168. Growth inhibition and competition assays on plates and in liquid cultures revealed that sublancin 168-mediated growth inhibition of susceptible B. subtilis and S. aureus cells is affected by the NaCl concentration in the growth medium. Added NaCl did not influence the production, activity, or stability of sublancin 168 but, instead, lowered the susceptibility of sensitive cells toward this lantibiotic. Importantly, the susceptibility of B. subtilis and S. aureus cells toward sublancin 168 was shown to depend on the presence of the large mechanosensitive channel of conductance MscL. In contrast, MscL was not involved in susceptibility toward the bacteriocin nisin or Pep5. Taken together, our unprecedented results demonstrate that MscL is a critical and specific determinant in bacterial sublancin 168 susceptibility that may serve either as a direct target for this lantibiotic or as a gate of entry to the cytoplasm. PMID:19738010

  17. Identification of a new Bacillus licheniformis strain producing a bacteriocin-like substance.

    Science.gov (United States)

    Guo, Yaoqi; Yu, Zhanqiao; Xie, Jianhua; Zhang, Rijun

    2012-06-01

    The emergence of antibiotic resistance has spurred a great number of studies for development of new antimicrobials in the past decade. The purpose of this study was to screen environmental samples for Bacillus strains producing potent antimicrobial agents. A new strain, which showed strong antimicrobial activity against Staphylococcus aureus and Salmonella enterica ser. Pullorum, was isolated from soil and designated as B116. This new isolate was identified as Bacillus licheniformis by morphological, biochemical and genetic analyses. The production of bacteriocin-like substance (BLS) started at early exponential phase and achieved highest level at early stationary phase. The BLS was precipitated by ammonium sulfate and its molecular mass was determined as ∼4 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Culture supernatant of the new isolate exhibited antimicrobial activity against both Gram-positive and Gram-negative bacteria, including Bacillus cereus, Staphylococcus aureus, Listeria monocytogenes, Micrococcus luteus, Escherichia coli, and Salmonella spp. The BLS was resistant to heat, acid and alkaline treatment. Activity of the BLS was totally lost after digestion by pronase and partially lost after digestion by papain and lipase. The new isolate and relevant BLS are potentially useful in food and feed applications. PMID:22752909

  18. Bacteriocin Serratine-P as a biological tool in the control of fire blight Erwinia amylovora.

    Science.gov (United States)

    Schoofs, H; Vandebroek, K; Pierrard, A; Thonart, P; Lepoivre, P; Beaudry, T; Deckers, T

    2002-01-01

    Fire blight, caused by the bacterium Erwinia amylovora (Burill Winslow et al.), is the most important bacterial disease in European pear growing. It can cause a lot of damage in some countries on apple and on pear trees in orchards and also in the fruit tree nurseries. In Belgium, the disease is present since 1972. Control of fire blight in Belgian fruit orchards is made on a broad basis of measurements in and around the fruit trees. The use of an antibiotic is allowed for application only during the primary blossom period under strict controlled regulations. The use of antobiotics in agriculture is strongly discussed on the European level today and will probably disappear in the near future. Therefore, the research on fire blight control concentrates on the possibilities of biological control with antagonistic bacteria such as Pantoea agglomerans (Erwinia herbicola), Bacillus subtilis or Pseudomonas syringae strain A 506. The use of Serratine-P, a phage tail-like bacteriocin, produced by Serratia plymiticum, shows an interesting antibacterial activity against Erwinia amylovora. Its mode of action consists in the perforation of the cytoplasmic membrane of the target cell, inducing perturbations in cellular exchanges and a final lysis of the bacterial cell. In this paper some trials are discussed on the use of Serratine-P at different doses and on different infection types on pear trees. The results indicate interesting protection possibilities on blossom- and fruit infections. PMID:12701444

  19. [Mode of action of plantaricin L-1, an antilisteria bacteriocin produced by Lactobacillus plantarum].

    Science.gov (United States)

    Zhou, Wei; Liu, Guo-rong; Li, Ping-lan; Dai, Yun-qing; Zhou, Kang

    2007-04-01

    Plantaricin L-1, an anti-Listeria bacteriocin, was produced by Lactobacillus plantarum and successfully purified by SP-Sepharose FF cation exchange chromatography. The mechanism on energized cells of Listeria monocytogenes was studied with purified plantaricin L-1. After adding plantaricin L-1 to Listeria monocytogenes at 64 AU/mL, leakage of intercellular K+ ions, inorganic phosphate, lactic dehydrogenase, UV-absorbing materials and the intracellular ATP was observed, and the action resulted in the dissipation of the membrane potential (delta psi) and pH gradient (delta psi), two components of the proton motive force (PMF). All the data suggested that the primary site of action of plantaricin L-1 was the cytoplasmic membrane of sensitive cells. By forming the nonselective pores which leak ions and small organic compounds plantaricin L-1 induced the cells death, this action was similar to membrane corruption caused by peptide effect. Penetrability increased due to the enlarged pore and dysfuction of membrane transporters, which ensured efficient killing of target bacteria. PMID:17552231

  20. Combining prebiotics with probiotic bacteria can enhance bacterial growth and secretion of bacteriocins.

    Science.gov (United States)

    Pranckutė, Raminta; Kaunietis, Arnoldas; Kuisienė, Nomeda; Čitavičius, Donaldas J

    2016-08-01

    There is a growing interest in supporting human health by using prebiotics, such as oligosaccharides, and beneficial bacteria, also called probiotics. Combining these two components we can develop synbiotics. In order to create successful combination of synbiotic it is very important to evaluate the influence of prebiotic oligosaccharides to probiotic bacteria and their behavior, such as growth and secretion of health related biomolecules, including bacteriocins. In this study seven type strains of probiotic bacteria (five Lactobacillus sp. and two Lactococcus sp.) and two Lactobacillus sp. strains, isolated from probiotic yoghurt, were cultivated with various commercially available and extracted oligosaccharides (OS). The aim of this study was to evaluate the influence of these OS on type and isolated bacterial strains growth and antibacterial activity. Obtained results suggest that combination of certain OS with probiotic strains may considerably improve their growth and/or antibacterial activity. We also determined the antibacterial activity spectrum of investigated strains with combination of OS against common food borne pathogens. Results of this work show that prebiotic OS can be useful for modulating probiotic bacteria growth, antibacterial activity and even specificity of this activity. PMID:27181578

  1. Tanshinone IIA Attenuates Renal Fibrosis after Acute Kidney Injury in a Mouse Model through Inhibition of Fibrocytes Recruitment

    Science.gov (United States)

    Jiang, Chunming; Shao, Qiuyuan; Jin, Bo; Zhang, Miao

    2015-01-01

    Acute kidney injury (AKI) is associated with an increased risk of developing advanced chronic kidney disease (CKD). Yet, effective interventions to prevent this conversion are unavailable for clinical practice. In this study, we examined the beneficial effects of Tanshinone IIA on renal fibrosis in a mouse model of folic acid induced AKI. We found that Tanshinone IIA treatment significantly attenuated the folic acid elicited kidney dysfunction on days 3, 14, and 28. This effect was concomitant with a much lessened accumulation of fibronectin and collagen in tubulointerstitium 28 days after folic acid injury, denoting an ameliorated renal fibrosis. The kidney protective and antifibrotic effect of Tanshinone IIA was likely attributable to an early inhibition of renal recruitment of fibrocytes positive for both CD45 and collagen I. Mechanistically, Tanshinone IIA treatment not only markedly diminished renal expression of chemoattractants for fibrocytes such as TGFβ1 and MCP-1, but also significantly reduced circulating fibrocytes at the acute phase of kidney injury. These data suggested that Tanshinone IIA might be a novel therapy for preventing progression of CKD after AKI. PMID:26885500

  2. TanshinoneIIA ameliorates inflammatory microenvironment of colon cancer cells via repression of microRNA-155.

    Science.gov (United States)

    Tu, Jiajie; Xing, Yingying; Guo, Yongjian; Tang, Feng; Guo, Le; Xi, Tao

    2012-12-01

    TanshinoneIIA, an active component derived from a traditional Chinese medicine, has anti-inflammatory and anti-cancer effect. However, the mechanisms underlying the interaction between anti-inflammation and anti-cancer of TanshinoneIIA remain elusive. In the present study, a cell model of inflammation between macrophages and colon cancer cells was used. The results showed that TanshinoneIIA inhibited the proliferation of inflammation-related colon cancer cells HCT116 and HT-29 by decreasing the production of inflammatory cytokines tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6), which generated by macrophage RAW264.7 cell line. We identified Phosphatidylinositol-3, 4, 5-trisphosphate 5-phosphatase 1 (SHIP1) was a bona fide target of miR-155. TanshinoneIIA restored the down-regulated level of SHIP1 protein after lipopolysaccharide (LPS)-stimulation in RAW264.7 cells. MicroRNA-155 (miR-155) was up-regulated in macrophages, possibly due to the concomitant increase of PU.1, a transcriptional activator of miR-155, accounting for decreased SHIP1. Treatment with TanshinoneIIA prevented increased PU.1 and hence increased miR-155, whereas aspirin could not. These findings support that the interruption of signal conduction between activated macrophages and colon cancer cells could be considered as a new therapeutic strategy and miR-155 could be a potential target for the prevention of inflammation-related cancer. PMID:22982040

  3. 产细菌素弯曲乳杆菌的分离鉴定及细菌素特性初步研究%Separation and identification of bacteriocin-producing Lactobacillus curvatus and characterization of its bacteriocin

    Institute of Scientific and Technical Information of China (English)

    任丽; 刘国荣; 王成涛; 孙宝国

    2013-01-01

    Bacteriocin-producing stain RX-6 was isolated from Spanish traditional Salami sausages. After eliminating some interference factors such as the organic acids,hydrogen peroxides and strain cells,the antimicrobial activity of the fermentation broth of strain RX-6 remained the same. By ammonium sulphate precipitation and dialysis,the activity was significantly enhanced. However,the substance was inactivated when treated with proteinase K. These results indicated the nature of antibacterial substance produced by strain RX-6 was protein. Based on morphological,physiological and biochemical characteristics, 16S rRNA gene sequence and phylogenic analysis, strain RX-6 was identified as Lactobacillus curvatus. Results obtained from characteristics analysis of the bacteriocin produced by strain RX-6 showed this bacteriocin still remained activated after the heat treatment at 121℃ for 20min and the pH activity range was 3 to 10, which indicated that it had strong heat stability and acid-base tolerance. Also, the bacteriocin could be inactivated by pepsin and trypsin.and partially inactivated by acid proteinase,which suggested that its use safety was very high. In addition,the bacteriocin had a broad inhibitory spectrum and could show inhibitory activity against Listeria spp., Staphylococcus spp., Pseudomonas spp. and Escherichia coli, which indicated that the bacteriocin had a potential application as natural food bio-preservatives in food industry.%从西班牙传统色拉米香肠中分离到一株产细菌素菌株RX-6,其发酵液在排除有机酸、过氧化氢及菌体细胞干扰后,抑菌活性基本无变化;经硫酸铵盐析及透析处理后,抑菌活性明显增强;蛋白酶K处理后,抑菌活性消失,表明起抑菌作用的是蛋白类物质.通过菌体形态观察、生理生化特征实验、16S rRNA序列比对及系统发育分析,鉴定菌株RX-6为弯曲乳杆菌(Lactobacillus curvatus).抑菌特性研究结果显示该菌株所产细菌素具

  4. Supersymmetric Intersecting D6-Branes and Fluxes in Massive Type IIA String Theory

    OpenAIRE

    Behrndt, K.; Cvetic, M.

    2004-01-01

    We study N=1 supersymmetric four-dimensional solutions of massive Type IIA supergravity with intersecting D6-branes in the presence NS-NS three-form fluxes. We derive N=1 supersymmetry conditions for the D6-brane and flux configurations in an internal manifold $X_6$ and derive the intrinsic torsion (or SU(3)-structure) related to the fluxes. In the absence of fluxes, N=1 supersymmetry implies that D6-branes wrap supersymmetric three-cycles of $X_6$ that intersect at angles of SU(3) rotations ...

  5. New industrial heat pump applications to a synthetic rubber plant. Final report, Phase IIA

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-12-31

    This report summarizes the results of the Phase IIA of the DOE sponsored study titled, Advanced Industrial Heat Pump Application and Evaluation. The scope of this phase of the study was to finalize the process design of the heat pump scheme, develop a process and instrumentation diagram, and a detailed cost estimate for the project. This information is essential for the site management to evaluate the economic viability and operability of the proposed heat pump design, prior to the next phase of installation and testing.

  6. Radiotherapy in stage IIA and IIB testicular seminoma with reduced portals: a prospective multicenter study

    International Nuclear Information System (INIS)

    Purpose: A prospective multicenter study was carried out to estimate the treatment outcome of radiotherapy in Stage II seminoma after the application of modern staging and radiotherapy techniques. The lower margin of the iliac field was positioned on the upper rim of the acetabulum to reduce the amount of scattered irradiation to the remaining testicle. Methods and Materials: The study was carried out in 25 centers in Germany. Patients with pure seminoma, negative AFP-values, and retroperitoneal lymph node metastases of less than 5 cm in diameter were entered into the study. All patients received a ventrodorsal opposed field irradiation of the para-aortic and the ipsilateral iliac lymph nodes. The fields extended from the top of the 11th thoracic vertebra to the top of the acetabulum. Patients in Stage IIA (lymph nodes <2 cm) received 30 Gy, and patients with Stage IIB (lymph nodes between 2 and 5 cm) 36 Gy total dose. Results: 39 patients in Stage IIA and 19 patients in Stage IIB were evaluated. After a median observation time of 37 months all patients are alive and disease free. Recurrence free survival in stage IIA was 100%. Two patients in Stage IIB experienced a recurrence 10 and 17 months after the end of radiotherapy. The actuarial recurrence free survival estimate in Stage IIB was 94.1% for 1 year and 87.4% for 2 years. One recurrence in Stage IIB occurred in the mediastinum, one in the mediastinum, and one the lung. Both patients could be salvaged by chemotherapy. There were no pelvic recurrences. The treatment was well tolerated, with nausea being the most common side effect (56.9% Grade 1, 15.5% Grade 2, and 8.6% Grade 3). Diarrhea occurred in 15.5% (Grade 1), 15.5% (Grade 2), and 5.2% (Grade 3) of the patients. Conclusions: The outcome of para-aortic and ipsilateral iliac irration in Stage IIA/B testicular seminoma is excellent with the currently available staging methods and treatment facilities. The treatment is well tolerated. The lower margin of the

  7. Release of Bacteriocins from Nanofibers Prepared with Combinations of Poly(D,L-lactide (PDLLA and Poly(Ethylene Oxide (PEO

    Directory of Open Access Journals (Sweden)

    Leon Dicks

    2011-03-01

    Full Text Available Plantaricin 423, produced by Lactobacillus plantarum, and bacteriocin ST4SA produced by Enterococcus mundtii, were electrospun into nanofibers prepared from different combinations of poly(D,L-lactide (PDLLA and poly(ethylene oxide (PEO dissolved in N,N-dimethylformamide (DMF. Both peptides were released from the nanofibers with a high initial burst and retained 88% of their original antimicrobial activity at 37 °C. Nanofibers have the potential to serve as carrier matrix for bacteriocins and open a new field in developing controlled antimicrobial delivery systems for various applications.

  8. Cloning and genetic and sequence analyses of the bacteriocin 21 determinant encoded on the Enterococcus faecalis pheromone-responsive conjugative plasmid pPD1.

    OpenAIRE

    H. Tomita; Fujimoto, S.; Tanimoto, K; Ike, Y

    1997-01-01

    The pheromone-responsive conjugative plasmid pPD1 (59 kb) of Enterococcus faecalis encodes the bacteriocin 21 (bac21) determinant. Cloning, transposon insertion mutagenesis and sequence analysis of the bac21 determinant showed that an 8.5-kb fragment lying between kb 27.1 and 35.6 of the pPD1 map is required for complete expression of the bacteriocin. The 8.5-kb fragment contained nine open reading frames (ORFs), bacA to bac1, which were oriented in the same (upstream-to-downstream) direction...

  9. Isolation and identification of Enterococcus faecium from seafoods: antimicrobial resistance and production of bacteriocin-like substances.

    Science.gov (United States)

    Valenzuela, Antonio Sánchez; Benomar, Nabil; Abriouel, Hikmate; Cañamero, Magdalena Martínez; Gálvez, Antonio

    2010-10-01

    A collection of isolates from uncooked seafoods (molluscs, fish, and fish fillets) were identified as Enterococcus faecium species and studied in further detail. Isolates were clustered in well-defined genomic groups according to food origin after ERIC-PCR analysis. Four isolates (FR 1-2, FB 1-3-B, FB 3-1, FTA 1-2) decarboxylated lysine, ornithine, and tyrosine. Isolate FR 1-2 also decarboxylated histidine. Most isolates were sensitive to antibiotics of clinical use, but resistance was detected more frequently towards nitrofurantoin (50%), erythromycin (33.33%) or rifampicin (33.33%) to quinupristin/dalfopristin (12.5%). Resistance to beta-lactams or vancomycin was not detected. The enterococcal antigen A was the presumed virulence trait detected most frequently. None of isolates carried haemolysin/cytolysin genes. Twelve isolates produced anti-listerial activity. Among them, seven isolates also produced bacteriocin-like inhibitory substances against other enterococci, and one isolate was also able to inhibit Staphylococcus aureus. Three isolates only were active against Listeria monocytogenes, and two only were active against enterococci. One bacteriocinogenic isolate carried the enterocin A structural gene, but genes corresponding to other enterocins (EntB, EntP, EntQ, Ent1071, EntL50A/EntL50B, and Ent31) were not detected. Bacteriocin-producing enterococci lacking undesirable traits (such as antibiotic resistance or biogenic amine production) or their produced bacteriocins could be potential candidates to aid in preservation of seafoods and other food products as well. PMID:20688238

  10. The genes involved in production of and immunity to sakacin A, a bacteriocin from Lactobacillus sake Lb706.

    OpenAIRE

    Axelsson, L.; Holck, A

    1995-01-01

    Sakacin A is a small, heat-stable, antilisterial bacteriocin produced by Lactobacillus sake Lb706. The nucleotide sequence of a 8,668-bp fragment, shown to contain all information necessary for sakacin A production and immunity, was determined. The sequence revealed the presence of two divergently transcribed operons. The first encompassed the structural gene sapA (previously designated sakA) and saiA, which encoded a putative peptide of 90 amino acid residues. The second encompassed sapK (pr...

  11. Purification and characterization of bacteriocin like substance produced from bacillus lentus with perspective of a new biopreservative for food preservation

    International Nuclear Information System (INIS)

    Molecular weight of bacteriocin like substance (BLIS) of a new strain of Bacillus lentus 121 was found to be approximately 11 kDa. Purification of BLIS was attained by single step gel exclusion chromatography. BLIS was characterized by studying the inhibitory spectrum. It was active at broad pH range, high temperature and high NaCl concentration and showed sensitivity to proteolytic enzymes like trypsin, alpha-chymotrypsin and papain, the characters desirable for food preservation. BLIS extended the shelf stability of milk upto 21 days as a biopreservative. (author)

  12. Type IIA photosensitivity and formation of pores in optical fibers under intense ultraviolet irradiation

    International Nuclear Information System (INIS)

    Formation of the type IIA Bragg gratings in germanosilicate optical fibers is studied. We report the observation of such a type of gratings in the standard single-mode fiber (Corning SMF-28) under different experimental conditions. A mechanism for the type IIA photosensitivity in optical fibers is proposed which is based on nucleation and evolution of pores from vacancy-type defects in fiber areas where a high level of mechanical stress is induced under intense ultraviolet (UV) light. Evolution of fiber core temperature under influence of a single 20 ns light pulse from a KrF excimer laser was measured and compared with theoretical calculations. It was shown that transient thermoinduced stress in the fiber core can achieve a level sufficient for effective nucleation of pores. A theory describing formation of pores in optical fibers has been developed and was used to estimate the pore nucleation rate, concentration, and other parameters of pore evolution for different levels of UV fluence and fiber core stress

  13. OECD/NEA burnup credit criticality benchmark. Result of phase IIA

    International Nuclear Information System (INIS)

    The report describes the final result of the Phase IIA of the Burnup Credit Criticality Benchmark conducted by OECD/NEA. In the Phase IIA benchmark problems, the effect of an axial burnup profile of PWR spent fuels on criticality (end effect) has been studied. The axial profiles at 10, 30 and 50 GWd/t burnup have been considered. In total, 22 results from 18 institutes of 10 countries have been submitted. The calculated multiplication factors from the participants have lain within the band of ± 1% Δk. For the irradiation up to 30 GWd/t, the end effect has been found to be less than 1.0% Δk. But, for the 50 GWd/t case, the effect is more than 4.0% Δk when both actinides and FPs are taken into account, whereas it remains less than 1.0% Δk when only actinides are considered. The fission density data have indicated the importance end regions have in the criticality safety analysis of spent fuel systems. (author)

  14. Force dependent biotinylation of myosin IIA by α-catenin tagged with a promiscuous biotin ligase.

    Directory of Open Access Journals (Sweden)

    Shuji Ueda

    Full Text Available Tissues and organs undergo constant physical perturbations and individual cells must respond to mechanical forces to maintain tissue integrity. However, molecular interactions underlying mechano-transduction are not fully defined at cell-cell junctions. This is in part due to weak and transient interactions that are likely prevalent in force-induced protein complexes. Using in situ proximal biotinylation by the promiscuous biotin ligase BirA tagged to α-catenin and a substrate stretch cell chamber, we sought to identify force-dependent molecular interactions surrounding α-catenin, an actin regulator at the sites of cadherin mediated cell-cell adhesion. While E-cadherin, β-catenin, vinculin and actin localize with α-catenin at cell-cell contacts in immuno-fluorescent staining, only β-catenin and plakoglobin were biotinylated, suggesting that this proximal biotinylation is limited to the molecules that are in the immediate vicinity of α-catenin. In mechanically stretched samples, increased biotinylation of non-muscle myosin IIA, but not myosin IIB, suggests close spatial proximity between α-catenin and myosin IIA during substrate stretching. This force-induced biotinylation diminished as myosin II activity was inhibited by blebbistatin. Taken together, this promising technique enables us to identify force sensitive complexes that may be essential for mechano-responses in force bearing cell adhesion.

  15. The effective action of D6-branes in mathcal{N} = 1 type IIA orientifolds

    Science.gov (United States)

    Kerstan, Max; Weigand, Timo

    2011-06-01

    We use a Kaluza-Klein reduction to compute the low-energy effective action for the massless modes of a spacetime-filling D6-brane wrapped on a special Lagrangian 3-cycle of a type IIA Calabi-Yau orientifold. The modifications to the characteristic data of the mathcal{N} = 1 bulk orientifold theory in the presence of a D6-brane are analysed by studying the underlying Type IIA supergravity coupled to the brane world volume in the democratic formulation and performing a detailed dualisation procedure. The mathcal{N} = 1 chiralcoordinates are found to be in agreement with expectations from mirror symmetry. We work out the Kähler potential for the chiral superfields as well as the gauge kinetic functions for the bulk and the brane gauge multiplets including the kinetic mixing between the two. The scalar potential resulting from the dualisation procedure can be formally interpreted in terms of a superpotential. Finally, the gauging of the Peccei-Quinn shift symmetries of the complex structure multiplets reproduces the D-term potential enforcing the calibration condition for special Lagrangian 3-cycles.

  16. The effective action of D6-branes in N=1 type IIA orientifolds

    CERN Document Server

    Kerstan, Max

    2011-01-01

    We use a Kaluza-Klein reduction to compute the low-energy effective action for the massless modes of a spacetime-filling D6-brane wrapped on a special Lagrangian 3-cycle of a type IIA Calabi-Yau orientifold. The modifications to the characteristic data of the N=1 bulk orientifold theory in the presence of a D6-brane are analysed by studying the underlying Type IIA supergravity coupled to the brane worldvolume in the democratic formulation and performing a detailed dualisation procedure. The N=1 chiral coordinates are found to be in agreement with expectations from mirror symmetry. We work out the Kahler potential for the chiral superfields as well as the gauge kinetic functions for the bulk and the brane gauge multiplets including the kinetic mixing between the two. The scalar potential resulting from the dualisation procedure can be formally interpreted in terms of a superpotential. Finally, the gauging of the Peccei-Quinn shift symmetries of the complex structure multiplets reproduces the D-term potential e...

  17. OECD/NEA burnup credit criticality benchmark. Result of phase IIA

    Energy Technology Data Exchange (ETDEWEB)

    Takano, Makoto; Okuno, Hiroshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1996-02-01

    The report describes the final result of the Phase IIA of the Burnup Credit Criticality Benchmark conducted by OECD/NEA. In the Phase IIA benchmark problems, the effect of an axial burnup profile of PWR spent fuels on criticality (end effect) has been studied. The axial profiles at 10, 30 and 50 GWd/t burnup have been considered. In total, 22 results from 18 institutes of 10 countries have been submitted. The calculated multiplication factors from the participants have lain within the band of {+-} 1% {Delta}k. For the irradiation up to 30 GWd/t, the end effect has been found to be less than 1.0% {Delta}k. But, for the 50 GWd/t case, the effect is more than 4.0% {Delta}k when both actinides and FPs are taken into account, whereas it remains less than 1.0% {Delta}k when only actinides are considered. The fission density data have indicated the importance end regions have in the criticality safety analysis of spent fuel systems. (author).

  18. Force dependent biotinylation of myosin IIA by α-catenin tagged with a promiscuous biotin ligase.

    Science.gov (United States)

    Ueda, Shuji; Blee, Alexandra M; Macway, Katherine G; Renner, Derrick J; Yamada, Soichiro

    2015-01-01

    Tissues and organs undergo constant physical perturbations and individual cells must respond to mechanical forces to maintain tissue integrity. However, molecular interactions underlying mechano-transduction are not fully defined at cell-cell junctions. This is in part due to weak and transient interactions that are likely prevalent in force-induced protein complexes. Using in situ proximal biotinylation by the promiscuous biotin ligase BirA tagged to α-catenin and a substrate stretch cell chamber, we sought to identify force-dependent molecular interactions surrounding α-catenin, an actin regulator at the sites of cadherin mediated cell-cell adhesion. While E-cadherin, β-catenin, vinculin and actin localize with α-catenin at cell-cell contacts in immuno-fluorescent staining, only β-catenin and plakoglobin were biotinylated, suggesting that this proximal biotinylation is limited to the molecules that are in the immediate vicinity of α-catenin. In mechanically stretched samples, increased biotinylation of non-muscle myosin IIA, but not myosin IIB, suggests close spatial proximity between α-catenin and myosin IIA during substrate stretching. This force-induced biotinylation diminished as myosin II activity was inhibited by blebbistatin. Taken together, this promising technique enables us to identify force sensitive complexes that may be essential for mechano-responses in force bearing cell adhesion. PMID:25806963

  19. Prevention and Therapeutic Effects and Mechanisms of Tanshinone IIA Sodium Sulfonate on Acute Liver Injury Mice Model

    Directory of Open Access Journals (Sweden)

    Lunjie Lu

    2016-01-01

    Full Text Available Tanshinone IIA sodium sulfonate (TSS is a water-soluble derivative of tanshinone IIA, which is the main pharmacologically active component of Salvia miltiorrhiza. This study aimed to verify the preventive and therapeutic effects of TSS and its combined therapeutic effects with magnesium isoglycyrrhizinate (MI in D-galactosamine- (D-Gal- induced acute liver injury (ALI in mice. The potential regulatory mechanisms of TSS on ALI were also examined. Our results may provide a basis for the development of novel therapeutics for ALI.

  20. Prevention and Therapeutic Effects and Mechanisms of Tanshinone IIA Sodium Sulfonate on Acute Liver Injury Mice Model

    Science.gov (United States)

    Lu, Lunjie; Zhou, Jun; Zhang, Jingying; Che, Jun; Jiao, Yang; Zhang, Yusong

    2016-01-01

    Tanshinone IIA sodium sulfonate (TSS) is a water-soluble derivative of tanshinone IIA, which is the main pharmacologically active component of Salvia miltiorrhiza. This study aimed to verify the preventive and therapeutic effects of TSS and its combined therapeutic effects with magnesium isoglycyrrhizinate (MI) in D-galactosamine- (D-Gal-) induced acute liver injury (ALI) in mice. The potential regulatory mechanisms of TSS on ALI were also examined. Our results may provide a basis for the development of novel therapeutics for ALI. PMID:27274751

  1. Complete Genome Sequence of Lactobacillus plantarum Strain B21, a Bacteriocin-Producing Strain Isolated from Vietnamese Fermented Sausage Nem Chua.

    Science.gov (United States)

    Golneshin, Aida; Adetutu, Eric; Ball, Andrew S; May, Bee K; Van, Thi Thu Hao; Smith, Andrew T

    2015-01-01

    Lactobacillus plantarum strain B21 was isolated from Vietnamese sausage (nem chua) and demonstrated broad antimicrobial activity due to the production of bacteriocins. Here, we report the complete genome sequence of this strain (3,284,260 bp). PMID:25838470

  2. Factors affecting production of an antilisterial bacteriocin by Carnobacterium piscicola strain A9b in laboratory media and model fish systems

    DEFF Research Database (Denmark)

    Himelbloom, B.; Nilsson, Lilian; Gram, Lone

    2001-01-01

    supernatant fluid of a stationary-phase culture. Increasing concentrations of NaCl (2-7%) reduced bacteriocin production and maximum cell density of C. piscicola A9b when grown in cooked fish juice at VC. Conclusions: Media composition, inoculum level and sodium chloride concentration affected production...

  3. DNA analysis of the genes encoding acidocin LF221 A and acidocin LF221 B, two bacteriocins produced by Lactobacillus gasseri LF221

    NARCIS (Netherlands)

    Majhenič, A.Č.; Venema, K.; Allison, G.E.; Matijašić, B.B.; Rogelj, I.; Klaenhammer, T.R.

    2004-01-01

    Lactobacillus gasseri LF221, an isolate from the feces of a child, produces two bacteriocins. Standard procedures for molecular techniques were used to locate, clone and sequence the fragments of LF221 chromosomal DNA carrying the acidocin LF221 A and B structural genes, respectively. Sequencing ana

  4. Identification and sequence analysis of pWcMBF8-1, a bacteriocin-encoding plasmid from the lactic acid bacterium Weissella confusa.

    Science.gov (United States)

    Malik, Amarila; Sumayyah, Sumayyah; Yeh, Chia-Wen; Heng, Nicholas C K

    2016-04-01

    Members of the Gram-positive lactic acid bacteria (LAB) are well-known for their beneficial properties as starter cultures and probiotics. Many LAB species produce ribosomally synthesized proteinaceous antibiotics (bacteriocins). Weissella confusa MBF8-1 is a strain isolated from a fermented soybean product that not only produces useful exopolysaccharides but also exhibits bacteriocin activity, which we call weissellicin MBF. Here, we show that bacteriocin production by W. confusa MBF8-1 is specified by a large plasmid, pWcMBF8-1. Plasmid pWcMBF8-1 (GenBank accession number KR350502), which was identified from the W. confusa MBF8-1 draft genome sequence, is 17 643 bp in length with a G + C content of 34.8% and contains 25 open reading frames (ORFs). Six ORFs constitute the weissellicin MBF locus, encoding three putative double-glycine-motif peptides (Bac1, Bac2, Bac3), an ABC transporter complex (BacTE) and a putative immunity protein (BacI). Two ORFs encode plasmid partitioning and mobilization proteins, suggesting that pWcMBF8-1 is transferable to other hosts. To the best of our knowledge, plasmid pWcMBF8-1 not only represents the first large Weissella plasmid to be sequenced but also the first to be associated with bacteriocin production in W. confusa. PMID:26976853

  5. Monitoring of multiple bacteriocins through a developed dual extraction protocol and comparison of HPLC-DAD with turbidometry as their quantification system.

    Science.gov (United States)

    Katharopoulos, Efstathios; Touloupi, Katerina; Touraki, Maria

    2016-08-01

    The present study describes the development of a simple and efficient screening system that allows identification and quantification of nine bacteriocins produced by Lactococcus lactis. Cell-free L. lactis extracts presented a broad spectrum of antibacterial activity, including Gram-negative bacteria, Gram-positive bacteria, and fungi. The characterization of their sensitivity to pH, and heat, showed that the extracts retained their antibacterial activity at extreme pH values and in a wide temperature range. The loss of antibacterial activity following treatment of the extracts with lipase or protease suggests a lipoproteinaceous nature of the produced antimicrobials. The extracts were subjected to a purification protocol that employs a two phase extraction using ammonium sulfate precipitation and organic solvent precipitation, followed by ion exchange chromatography, solid phase extraction and HPLC. In the nine fractions that presented antimicrobial activity, bacteriocins were quantified by the turbidometric method using a standard curve of nisin and by the HPLC method with nisin as the external standard, with both methods producing comparable results. Turbidometry appears to be unique in the qualitative determination of bacteriocins but the only method suitable to both separate and quantify the bacteriocins providing increased sensitivity, accuracy, and precision is HPLC. PMID:27282100

  6. Description of two Enterococcus strains isolated from traditional Peruvian artisanal-produced cheeses with a bacteriocin-like inhibitory activity

    Directory of Open Access Journals (Sweden)

    Aguilar Galvez A.

    2009-01-01

    Full Text Available The aim of this work was to isolate and to characterize strains of lactic acid bacteria (LAB with bacteriocin-like inhibitory activity from 27 traditional cheeses artisanal-produced obtained from different Peruvian regions. Twenty Gram+ and catalasenegative strains among 2,277 isolates exhibited bacteriocin-like inhibitory activity against Listeria monocytogenes CWBIB2232 as target strain. No change in inhibitory activity was observed after organic acid neutralization and treatment with catalase of the cell-free supernatant (CFS. The proteinic nature of the antimicrobial activity was confirmed for the twenty LAB strains by proteolytic digestion of the CFS. Two strains, CWBI-B1431 and CWBI-B1430, with the best antimicrobial activity were selected for further researches. These strains were taxonomically identified by phenotypic and genotypic analyses as Enterococcus mundtii (CWBI-B1431 and Enterococcus faecium (CWBI-B1430. The two strains were sensitive to vancomycin (MIC 2 μg.ml-1 and showed absence of haemolysis.

  7. Characterization of a bacteriocin-like substance produced from a novel isolated strain of Bacillus subtilis SLYY-3

    Science.gov (United States)

    Li, Junfeng; Li, Hongfang; Zhang, Yuanyuan; Duan, Xiaohui; Liu, Jie

    2014-12-01

    In the present research, the strain SLYY-3 was isolated from sediments of Jiaozhou Bay, Qingdao, China. The strain SLYY-3, which produced a bacteriocin-like substance (BLS), was characterized to be a strain of Bacillus subtillis by biochemical profiling and 16S rDNA sequence analysis. It is the first time to report that Bacillus subtilis from Jiaozhou Bay sediments could produce a BLS. The BLS of B. subtillis SLYY-3 exhibited strong inhibitory activity against gram-positive bacteria (including Staphylococcus aureus and B. subtillis) and some fungi (including Penicillium glaucum, Aspergillus niger and Aspergillus flavus). The antimicrobial activity was detected from culture in the exponential growth phase and reached its maximum when culture entered into stationary growth phase. It was thermo-tolerant even when being kept at 100°C for 60 min without losing any activity and stable over a wide pH range from 1.0 to 12.0 while being inactivated by proteolytic enzyme and trypsin, indicating the proteinaceous nature of the BLS. The BLS was purified by precipitation with hydrochloric acid (HCl) and gel filteration (Sephadex G-100). SDS-PAGE analysis of the extracellular peptides of SLYY-3 revealed a bacteriocin-like protein with a molecular mass of 66 kDa. Altogether, these characteristics indicate the potential of the BLS for food industry as a protection against pathogenic and spoilage microorganisms.

  8. Production of bioactive substances by intestinal bacteria as a basis for explaining probiotic mechanisms: bacteriocins and conjugated linoleic acid.

    Science.gov (United States)

    O'Shea, Eileen F; Cotter, Paul D; Stanton, Catherine; Ross, R Paul; Hill, Colin

    2012-01-16

    The mechanisms by which intestinal bacteria achieve their associated health benefits can be complex and multifaceted. In this respect, the diverse microbial composition of the human gastrointestinal tract (GIT) provides an almost unlimited potential source of bioactive substances (pharmabiotics) which can directly or indirectly affect human health. Bacteriocins and fatty acids are just two examples of pharmabiotic substances which may contribute to probiotic functionality within the mammalian GIT. Bacteriocin production is believed to confer producing strains with a competitive advantage within complex microbial environments as a consequence of their associated antimicrobial activity. This has the potential to enable the establishment and prevalence of producing strains as well as directly inhibiting pathogens within the GIT. Consequently, these antimicrobial peptides and the associated intestinal producing strains may be exploited to beneficially influence microbial populations. Intestinal bacteria are also known to produce a diverse array of health-promoting fatty acids. Indeed, certain strains of intestinal bifidobacteria have been shown to produce conjugated linoleic acid (CLA), a fatty acid which has been associated with a variety of systemic health-promoting effects. Recently, the ability to modulate the fatty acid composition of the liver and adipose tissue of the host upon oral administration of CLA-producing bifidobacteria and lactobacilli was demonstrated in a murine model. Importantly, this implies a potential therapeutic role for probiotics in the treatment of certain metabolic and immunoinflammatory disorders. Such examples serve to highlight the potential contribution of pharmabiotic production to probiotic functionality in relation to human health maintenance. PMID:21742394

  9. Purification and characterization of a novel bacteriocin produced by Lactobacillus crustorum MN047 isolated from koumiss from Xinjiang, China.

    Science.gov (United States)

    Yi, Lanhua; Dang, Ying; Wu, Jingli; Zhang, Lihui; Liu, Xiaojiao; Liu, Bianfang; Zhou, Yuan; Lu, Xin

    2016-09-01

    The growing emergence of antibiotic-resistant bacteria in the food industry needs to be controlled with effective antimicrobials. In this study, bacteriocin MN047 A (BMA) was found to have antibacterial activity against multidrug-resistant bacteria. It was produced by Lactobacillus crustorum MN047, which was first isolated from koumiss, a traditional fermented dairy product from Xinjiang Autonomous Region, China. It was purified by ammonium sulfate precipitation, ion-exchange chromatography, and reversed-phase chromatography. It had a low molecular mass of 1,770.89 Da according to matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, and the sequence was identified as QLPWQILGIVAGMFQA by liquid chromatography-tandem mass spectrometry analysis and MASCOT searching. It was proteinaceous in nature: the bacteriocin was digested by protease but not by α-amylase or lipase. It showed broad pH toleration (pH 2-11), good thermostability, and good storage stability. It had a broad inhibitory spectrum, including both gram-positive and gram-negative bacteria. Growth curve and time-kill kinetics indicated that it was bactericidal to the indicator strains, and this finding was verified by scanning electron microscope and transmission electron microscope after treatment with BMA. As well, BMA halted the growth of Staphylococcus aureus and Escherichia coli in the G1 and G2/M phases according to cell-cycle analysis by flow cytometry, indicating that BMA had comprehensive inhibitory effects against foodborne pathogens. PMID:27423943

  10. Class size versus class composition

    DEFF Research Database (Denmark)

    Jones, Sam

    Raising schooling quality in low-income countries is a pressing challenge. Substantial research has considered the impact of cutting class sizes on skills acquisition. Considerably less attention has been given to the extent to which peer effects, which refer to class composition, also may affect...

  11. Anti-inflammatory effects of tanshinone IIA on radiation-induced microglia BV-2 cells inflammatory response

    DEFF Research Database (Denmark)

    Dong, Xiaorong; Dong, Jihua; Zhang, Ruiguang;

    2009-01-01

    Tanshinone II(A) exerts anti-inflammatory properties by suppressing the transcription of proinflammatory cytokine genes that might be associated with the NF-kappabeta signaling pathway. It is postulated that irradiation causes immediate cellular reaction, and that double-strand breaks trigger the molecular...

  12. 最新IIA"内部审计"定义中文翻译新旧比较

    Institute of Scientific and Technical Information of China (English)

    石绍炳

    2007-01-01

    @@ 1999年6月,国际内部审计师协会(以下简称为IIA)批准了关于内部审计的新定义,其英文如下:"Internal Auditing is an independent,objective assurance and consulting activity designed to add value and improve an organization's operations.

  13. Silicon Phthalocyanine 4 and Photodynamic Therapy in Stage IA-IIA Cutaneous T-Cell Non-Hodgkin Lymphoma

    Science.gov (United States)

    2015-12-03

    Recurrent Cutaneous T-cell Non-Hodgkin Lymphoma; Recurrent Mycosis Fungoides/Sezary Syndrome; Stage I Cutaneous T-cell Non-Hodgkin Lymphoma; Stage IA Mycosis Fungoides/Sezary Syndrome; Stage IB Mycosis Fungoides/Sezary Syndrome; Stage II Cutaneous T-cell Non-Hodgkin Lymphoma; Stage IIA Mycosis Fungoides/Sezary Syndrome

  14. Investigation of the effect of tanshinone IIA on nitric oxide production in human vascular endothelial cells by fluorescence imaging

    Science.gov (United States)

    Huang, Ke-Jing; Wang, Hong; Xie, Wan-Zhen; Zhang, Hua-Shan

    2007-12-01

    Nitric oxide (NO) has been proved to be a potent vasodilator that played an important role in regulating vascular tones. Tanshinone, one of the active components of Radix Salvia miltiorrhiza, was used widely in clinics in China for treating cardiovascular diseases. The objective of this study was to sensitively and specifically investigate the effects of tanshinone IIA, one important pharmacological constituent of tanshinone, on the release of NO from human vascular endothelial cells (HVECs) by fluorescence imaging with an excellent fluorescent probe 1,3,5,7-tetramethyl-2,6-dicarbethoxy-8-(3',4'-diaminophenyl)-difluoroboradiaza- s-indacence (TMDCDABODIPY). After cells were incubated with tanshinone IIA, TMDCDABODIPY was employed to label NO. Following the tagging, real-time imaging of NO release from the cells was performed with inverted fluorescence microscope. The results of the experiments showed that tanshinone IIA could induce NO production significantly enhanced in HVECs. The activation of NO by tanshinone IIA may be employed therapeutically in modulating NO production in HVECs.

  15. Purification and Characterization of Plantaricin JLA-9: A Novel Bacteriocin against Bacillus spp. Produced by Lactobacillus plantarum JLA-9 from Suan-Tsai, a Traditional Chinese Fermented Cabbage.

    Science.gov (United States)

    Zhao, Shengming; Han, Jinzhi; Bie, Xiaomei; Lu, Zhaoxin; Zhang, Chong; Lv, Fengxia

    2016-04-01

    Bacteriocins are ribosomally synthesized peptides with antimicrobial activity produced by numerous bacteria. A novel bacteriocin-producing strain, Lactobacillus plantarum JLA-9, isolated from Suan-Tsai, a traditional Chinese fermented cabbage, was screened and identified by its physiobiochemical characteristics and 16S rDNA sequence analysis. A new bacteriocin, designated plantaricin JLA-9, was purified using butanol extraction, gel filtration, and reverse-phase high-performance liquid chromatography. The molecular mass of plantaricin JLA-9 was shown to be 1044 Da by MALDI-TOF-MS analyses. The amino acid sequence of plantaricin JLA-9 was predicted to be FWQKMSFA by MALDI-TOF-MS/MS, which was confirmed by Edman degradation. This bacteriocin exhibited broad-spectrum antibacterial activity against Gram-positive and Gram-negative bacteria, especially Bacillus spp., high thermal stability (20 min, 121 °C), and narrow pH stability (pH 2.0-7.0). It was sensitive to α-chymotrypsin, pepsin, alkaline protease, and papain. The mode of action of this bacteriocin responsible for outgrowth inhibition of Bacillus cereus spores was studied. Plantaricin JLA-9 had no detectable effects on germination initiation over 1 h on monitoring the hydration, heat resistance, and 2,6-pyridinedicarboxylic acid (DPA) release of spores. Rather, germination initiation is a prerequisite for the action of plantaricin JLA-9. Plantaricin JLA-9 inhibited growth by preventing the establishment of oxidative metabolism and disrupting membrane integrity in germinating spores within 2 h. The results suggest that plantaricin JLA-9 has potential applications in the control of Bacillus spp. in the food industry. PMID:26985692

  16. PRESERVATIVE POTENTIAL OF PURIFIED BACTERIOCIN PRODUCED FROM BREVIBACILLUS BORSTELENSIS AG1 ISOLATED FROM MARCHA – A TRADITIONAL WINE STARTER CULTURE CAKE IN TOMATO PASTE

    Directory of Open Access Journals (Sweden)

    Anupama Gupta

    2015-04-01

    Full Text Available Purified bacteriocin produced from Brevibacillus borstelensis AG1 isolated from Marcha a local wine starter herbal cake, was used to enhance the shelf life of tomato paste. Preservative effect of purified bacteriocin was studied for nine days in tomato paste inoculated with food borne pathogens and was compared to commercial biopreservative – nisin and chemical preservative – sodium benzoate. The indicator strains i.e. Listeria monocytogenes MTCC839, Bacillus subtilis CRI and Clostridium perfringens MTCC1739 were used at the amount 8.16, 8.13 and 8.18 log CFU/ml. Viable cells were counted periodically and a consistent reduction in number of viable cells of each tested pathogen was observed. It was found antagonistic against L. monocytogenes MTCC839, B. subtilis CRI and C. perfringes MTCC1739 which are the most challengeable and food borne pathogens found in processed vegetables products. Purified bacteriocin was found active over a wide pH range i.e. 3.0 to 11.0 and was able to withstand temperature up to 100oC. It showed a better preservative potential by reducing pathogenic load of the tested strains (by 2.02, 2.05 and 2.02 log cycles (CFU/ml of L. monocytogenes MTCC839, B. subtilis CRI and C. perfringes MTCC1739, respectively in tomato paste as compared to control (without bacteriocin. This proves efficiency of bacteriocin produced by B. borstelensis AG1 as biopreservative to enhance the safety and shelf life of acidic foods.

  17. Word classes

    DEFF Research Database (Denmark)

    Rijkhoff, Jan

    2007-01-01

    This article provides an overview of recent literature and research on word classes, focusing in particular on typological approaches to word classification. The cross-linguistic classification of word class systems (or parts-of-speech systems) presented in this article is based on statements found...... in grammatical descriptions of some 50 languages, which together constitute a representative sample of the world’s languages (Hengeveld et al. 2004: 529). It appears that there are both quantitative and qualitative differences between word class systems of individual languages. Whereas some languages...... employ a parts-of-speech system that includes the categories Verb, Noun, Adjective and Adverb, other languages may use only a subset of these four lexical categories. Furthermore, quite a few languages have a major word class whose members cannot be classified in terms of the categories Verb – Noun...

  18. Neveu-Schwarz 5-branes in type-IIA supergravity and gravitational anomalies

    International Nuclear Information System (INIS)

    We construct a gravitational-anomaly-free effective action for the coupled system of type-IIA D=10 dynamical supergravity interacting with a NS5-brane. The NS5-brane is considered as elementary in that the associated current is a δ function supported on its world volume. Our approach is based on a Chern kernel which encodes the singularities of the three-form field strength near the brane in an SO(4)-invariant way and provides a solution for its Bianchi identity in terms of a two-form potential. A dimensional reduction of the recently constructed anomaly-free effective action for an elementary M5-brane in D=11 is seen to reproduce our ten-dimensional action. The Chern-kernel approach provides in particular a concrete realization of the anomaly cancellation mechanism envisaged by Witten

  19. Group IIA β-diketonate compounds as CVD-precursors for high-Tc superconductors

    International Nuclear Information System (INIS)

    The advent of the high temperature superconducting metal oxides (SMO) has prompted an increasing number of studies aimed at the development of new routes to their synthesis in particular in the form of thin films. The preferred method in this regard has been that of chemical vapor deposition (CVD); however, significant difficulties have been associated with the efficacy of commercial precursors for the Group IIA metals in particular those of the β-diketonates of barium, whose coordinative unsaturation leads to cluster formation. The development of alternative β-diketonate precursor systems has focused upon the synthesis of stable Lewis-acid base complexes by either inter- or intra- molecular stabilization. The results of these studies are described herein, along with a review of the structural studies of the parent β-diketonate complexes and their decomposition products. (orig.)

  20. Effect of oral treatment with pantethine on platelet and plasma phospholipids in IIa hyperlipoproteinemia.

    Science.gov (United States)

    Prisco, D; Rogasi, P G; Matucci, M; Paniccia, R; Abbate, R; Gensini, G F; Neri Serneri, G G

    1987-03-01

    In a single-blind, crossover, completely randomized study, the effects of oral treatment with pantethine or placebo on fatty acid composition of plasma and platelet phospholipids were investigated in 10 IIa hyperlipoproteinemic patients. A significant decrease of total cholesterol and total phospholipids was observed both in plasma and in platelets after a twenty-eight-day treatment. In plasma, pantethine induced a decrease of the ratio sphingomyelin/phosphatidylcholine. Moreover, a relative increase of n3-polyunsaturated fatty acids both in plasma and in platelet phospholipids and a decrease of arachidonic acid in plasma phospholipids were observed. These results indicate that pantethine can affect plasma and platelet lipid composition with possibly favorable influences on the determinants of cell membrane fluidity. PMID:3551695

  1. Biological evaluation and molecular modelling study of thiosemicarbazide derivatives as bacterial type IIA topoisomerases inhibitors.

    Science.gov (United States)

    Paneth, Agata; Stączek, Paweł; Plech, Tomasz; Strzelczyk, Aleksandra; Dzitko, Katarzyna; Wujec, Monika; Kuśmierz, Edyta; Kosikowska, Urszula; Grzegorczyk, Agnieszka; Paneth, Piotr

    2016-01-01

    In the present article, we describe the inhibitory potency of nine thiosemicarbazide derivatives against bacterial type IIA topoisomerases, their antibacterial profile and molecular modelling evaluation. We found that one of the tested compounds, compound 7, significantly inhibits activity of Staphylococcus aureus DNA gyrase with an IC(50) below 15 μM. Besides, this compound displays antibacterial activity on reference Staphylococuss spp. and Enterococcus faecalis strains as well as clinical S. aureus isolates at non-cytotoxic concentrations in mammalian cells with MIC values ranging from 16 to 32 μg/mL thereby indicating, in some cases, equipotent or even more effective action than standard drugs such as vancomycin, ampicillin and nitrofurantoin. The computational studies showed that both molecular geometry and the electron density distribution have a great impact on antibacterial activity of thiosemicarbazide derivatives. PMID:25792505

  2. A CASE REPORT OF A VARIANT OF LUMBO-SACRAL TRANSITION VERTEBRAE: CASTELLVI TYPE IIA SACRALISATION

    Directory of Open Access Journals (Sweden)

    Subhendu Pandit

    2015-09-01

    Full Text Available Lumbosacral transitional vertebra (LSTV are congenital anomalies of the lumbosacral spine causing sacralisation or lumbarisation. Sacralisation has been defined as an abnormality where one of the transverse processes of L5 vertebra may articulate or fuse with the sacrum. The sacralisation has been studied for almost a century for its association with low back pain as “Bertolotti Syndrome”, but there are studies for and against its association. Castellvi in 1984 had propounded a radiographical classification identifying sacralisation in four sub types. Out of this, the Type IIA, is the least prevalent wherein there is a unilateral articulation of the L5 transverse process with the sacral ala. Inspite of the controversy, there is a high association of low back pain with disc degeneration, nerve root compression and degenerative facet joints observed with this condition. It is a widely researched vertebral anomaly for its anatomical, developmental and clinical ramifications.

  3. The secretory phospholipase A2 group IIA: a missing link between inflammation, activated renin-angiotensin system, and atherogenesis?

    Directory of Open Access Journals (Sweden)

    Dimitar Divchev

    2008-06-01

    Full Text Available Dimitar Divchev, Bernhard SchiefferDepartment of Cardiology and Angiology, Medizinische Hochschule Hannover, GermanyAbstract: Inflammation, lipid peroxidation and chronic activation of the renin–angiotensin system (RAS are hallmarks of the development of atherosclerosis. Recent studies have suggested the involvement of the pro-inflammatory secretory phospholipase A2 (sPLA2-IIA in atherogenesis. This enzyme is produced by different cell types through stimulation by proinflammatory cytokines. It is detectable in the intima and in media smooth muscle cells, not only in atherosclerotic lesions but also in the very early stages of atherogenesis. sPLA2-IIA can hydrolyse the phospholipid monolayers of low density lipoproteins (LDL. Such modified LDL show increased affinity to proteoglycans. The modified particles have a greater tendency to aggregate and an enhanced ability to insert cholesterol into cells. This modification may promote macrophage LDL uptake leading to the formation of foam cells. Furthermore, sPLA2-IIA is not only a mediator for localized inflammation but may be also used as an independent predictor of adverse outcomes in patients with stable coronary artery disease or acute coronary syndromes. An interaction between activated RAS and phospholipases has been indicated by observations showing that inhibitors of sPLA2 decrease angiotensin (Ang II-induced macrophage lipid peroxidation. Meanwhile, various interactions between Ang II and oxLDL have been demonstrated suggesting a central role of sPLA2-IIA in these processes and offering a possible target for treatment. The role of sPLA2-IIA in the perpetuation of atherosclerosis appears to be the missing link between inflammation, activated RAS and lipidperoxidation.Keywords: secretory phospholipase A2, lipoproteins, renin-angiotensin system, inflammation, atherosclerosis

  4. Involvement of aph(3‘-IIa in the formation of mosaic aminoglycoside resistance genes in natural environments

    Directory of Open Access Journals (Sweden)

    Markus eWoegerbauer

    2015-05-01

    Full Text Available Intragenic recombination leading to mosaic gene formation is known to alter resistance profiles for particular genes and bacterial species. Few studies have examined to what extent aminoglycoside resistance genes undergo intragenic recombination.We screened the GenBank database for mosaic gene formation in homologs of the aph(3’-IIa (nptII gene. APH(3’-IIa inactivates important aminoglycoside antibiotics. The gene is widely used as a selectable marker in biotechnology and enters the environment via laboratory discharges and the release of transgenic organisms. Such releases may provide opportunities for recombination in competent environmental bacteria.The retrieved GenBank sequences were grouped in 3 datasets comprising river water samples, duck pathogens and full-length variants from various bacterial genomes and plasmids. Analysis for recombination in these datasets was performed with the Recombination Detection Program, RDP4, and the Genetic Algorithm for Recombination Detection, GARD.From a total of 89 homologous sequences, 83% showed 99% - 100% sequence identity with aph(3’-IIa originally described as part of transposon Tn5. Fifty one were unique sequence variants eligible for recombination analysis. Only a single recombination event was identified with high confidence and indicated the involvement of aph(3’-IIa in the formation of a mosaic gene located on a plasmid of environmental origin in the multi-resistant isolate Pseudomonas aeruginosa PA96. The available data suggest that aph(3’-IIa is not an archetypical mosaic gene as the divergence between the described sequence variants and the number of detectable recombination events is low. This is in contrast to the numerous mosaic alleles reported for certain penicillin or tetracycline resistance determinants.

  5. Involvement of aph(3′)-IIa in the formation of mosaic aminoglycoside resistance genes in natural environments

    Science.gov (United States)

    Woegerbauer, Markus; Kuffner, Melanie; Domingues, Sara; Nielsen, Kaare M.

    2015-01-01

    Intragenic recombination leading to mosaic gene formation is known to alter resistance profiles for particular genes and bacterial species. Few studies have examined to what extent aminoglycoside resistance genes undergo intragenic recombination. We screened the GenBank database for mosaic gene formation in homologs of the aph(3′)-IIa (nptII) gene. APH(3′)-IIa inactivates important aminoglycoside antibiotics. The gene is widely used as a selectable marker in biotechnology and enters the environment via laboratory discharges and the release of transgenic organisms. Such releases may provide opportunities for recombination in competent environmental bacteria. The retrieved GenBank sequences were grouped in three datasets comprising river water samples, duck pathogens and full-length variants from various bacterial genomes and plasmids. Analysis for recombination in these datasets was performed with the Recombination Detection Program (RDP4), and the Genetic Algorithm for Recombination Detection (GARD). From a total of 89 homologous sequences, 83% showed 99–100% sequence identity with aph(3′)-IIa originally described as part of transposon Tn5. Fifty one were unique sequence variants eligible for recombination analysis. Only a single recombination event was identified with high confidence and indicated the involvement of aph(3′)-IIa in the formation of a mosaic gene located on a plasmid of environmental origin in the multi-resistant isolate Pseudomonas aeruginosa PA96. The available data suggest that aph(3′)-IIa is not an archetypical mosaic gene as the divergence between the described sequence variants and the number of detectable recombination events is low. This is in contrast to the numerous mosaic alleles reported for certain penicillin or tetracycline resistance determinants. PMID:26042098

  6. Tanshinone IIA increases the bystander effect of herpes simplex virus thymidine kinase/ganciclovir gene therapy via enhanced gap junctional intercellular communication.

    Directory of Open Access Journals (Sweden)

    Jianyong Xiao

    Full Text Available The bystander effect is an intriguing phenomenon by which adjacent cells become sensitized to drug treatment during gene therapy with herpes simplex virus thymidine kinase/ganciclovir (HSV-tk/GCV. This effect is reported to be mediated by gap junctional intercellular communication (GJIC, and therefore, we postulated that upregulation of genes that facilitate GJIC may enhance the HSV-tk/GCV bystander effect. Previous findings have shown Tanshinone IIA (Tan IIA, a chemical substance derived from a Chinese medicine herb, promotes the upregulation of the connexins Cx26 and Cx43 in B16 cells. Because gap junctions are formed by connexins, we hypothesized that Tan IIA might increase GJIC. Our results show that Tan IIA increased GJIC in B16 melanoma cells, leading to more efficient GCV-induced bystander killing in cells stably expressing HSV-tk. Additionally, in vivo experiments demonstrated that tumors in mice with 10% HSV-tk positive B16 cells and 90% wild-type B16 cells became smaller following treatment with the combination of GCV and Tan IIA as compared to GCV or Tan IIA alone. These data demonstrate that Tan IIA can augment the bystander effect of HSV-tk/GCV system through increased gap junction coupling, which adds strength to the promising strategy that develops connexins inducer to potentiate the effects of suicide gene therapy.

  7. Tanshinone IIA inhibits human breast cancer MDA-MB-231 cells by decreasing LC3-II, Erb-B2 and NF-κBp65

    OpenAIRE

    Su, Chin-Cheng; Chien, Su-Yu; Kuo, Shou-Jen; Chen, Yao-Li; CHENG, CHUN-YUAN; Chen, Dar-Ren

    2012-01-01

    The ability of tanshinone IIA (Tan-IIA) to inhibit the proliferation of human breast cancer cell lines in vitro and in vivo is well documented. However, the molecular mechanisms have not been fully elucidated. In the present study, MDA-MB-231 cells were treated with different concentrations of Tan-IIA for 48 h, followed by protein extraction for western blotting. For an in vivo study, MDA-MB-231 cells were implanted directly into female SCID mice which were divided randomly into three groups ...

  8. Achievement of 30% conversion from O II to O II(a1Δ) at 50 torr using an integrally cooled, controlled avalanche ionized electric O II(a1Δ) generator

    Science.gov (United States)

    Hill, Alan E.

    2007-06-01

    The electric oxygen iodine laser (EOIL) offers a vastly more practical, implementable, and safer alternative to its predecessor, the chemical oxygen iodine laser (COIL), particularly for airborne or other mobile military applications. Despite its promise and after 25 years effort, numerous laboratories around the world have not succeeded in providing the known basic physical requirements needed to electrically convert O2 into O II(a1Δ)with the fractional yields and efficiencies needed to make a practical laser. Hence, as of this date, the world record power generated from an EOIL device is only 5 watts. In this paper, a 30% conversion from O II into O II(a1Δ) operating at substantial oxygen mass flow rates (0.090 moles O2/sec at 50 torr) and 40% electrical efficiency is reported. The O II(a1Δ) flow stream being produced carries 2400 watts. Gain measurements are currently in progress, to be followed shortly by power extraction. Current conditions imply that initial power extraction could push beyond 1 KW. Efforts to date have failed to generate substantial laser power because critical criteria have not been met. In order to achieve good O II(a1Δ) fractional yield, it is normally mandatory to impart on the order of 100 KJ/mole O II while efficiently removing the waste heat energy from the generator so that less than a few hundred degrees Kelvin rise occurs due to gas heating. The generator must be excited by an electric field on the order of 10 Td. This is far below glow potential; hence, a fully externally sustained plasma generation technique is required. Ionization is supplied by means of applying short (tens of nanosecond) pulses to the O II(a1Δ) generator at 50,000 PPS, which are on the order of ten times breakdown potential. This enables a quasi-steady adjustable DC current to flow through the generator, being conducted by application of a DC, 10 to 14 Td pump E-field. This field is also independently tunable. The result is that up to 180 KJ/mole O II gets

  9. Antibacterial activity and genotypic-phenotypic characteristics of bacteriocin-producing Bacillus subtilis KKU213: potential as a probiotic strain.

    Science.gov (United States)

    Khochamit, Nalisa; Siripornadulsil, Surasak; Sukon, Peerapol; Siripornadulsil, Wilailak

    2015-01-01

    The antimicrobial activity and probiotic properties of Bacillus subtilis strain KKU213, isolated from local soil, were investigated. The cell-free supernatant (CFS) of a KKU213 culture containing crude bacteriocins exhibited inhibitory effects on Gram-positive bacteria, including Bacillus cereus, Listeria monocytogenes, Micrococcus luteus, and Staphylococcus aureus. The antibacterial activity of the CFS precipitated with 40% ammonium sulfate (AS) remained even after treatment at 60 and 100 °C, at pH 4 and 10 and with proteolytic enzymes, detergents and heavy metals. When analyzed by SDS-PAGE and overlaid with the indicator strains B. cereus and S. aureus, the 40% AS precipitate exhibited inhibitory activity on proteins smaller than 10 kDa. However, proteins larger than 25 kDa and smaller than 10 kDa were still observed on a native protein gel. Purified subtilosin A was prepared by Amberlite XAD-16 bead extraction and HPLC and analyzed by Nano-LC-QTOF-MS. Its molecular mass was found to be 3.4 kDa, and it retained its antibacterial activity. These results are consistent with the detection of the anti-listerial subtilosin A gene of the sbo/alb cluster in the KKU213 strain, which is 100% identical to that of B. subtilis subsp. subtilis 168. In addition to stable and cyclic subtilosin A, a mixture of many extracellular antibacterial peptides was also detected in the KKU213 culture. The KKU213 strain produced extracellular amylase, cellulase, lipase and protease, is highly acid-resistant (pH 2) when cultured in inulin and promotes health and reduces infection of intestinally colonized broiler chickens. Therefore, we propose that bacteriocin-producing B. subtilis KKU213 could be used as a potential probiotic strain or protective culture. PMID:25440998

  10. Multiple Authorisation: The Legal Complexity of Desentralisasi in Indonesia and the Potential Contribution of IIAs in Reducing Confusion

    Directory of Open Access Journals (Sweden)

    Michael Ewing-Chow

    2015-12-01

    Full Text Available Decentralisation system in Indonesia was introduced after the fall of the former President Soeharto with the objective of ensuring good governance and equitable development across all regions in the country. Unfortunately, the implementation of desentralisasi has been complicated. Some scholars have suggested that the model was flawed as it did not consider Indonesia’s context of less developed administrative institutions in the regions. Not only did desentralisasi cause headaches for the government, it also created confusion for foreign investors. Consequently, it affects the investment climate in the country and undermines the perception of Indonesia as an attractive place to invest in. In certain cases, desentralisasi has also led to claims by foreign investors for investor-State arbitration under Indonesia’s international investment agreements (IIAs. This paper analyses the problems of desentralisasi in Indonesia, its effects to foreign investors and suggests ways to alleviate the problems by modifying and using Indonesia’s IIAs effectively.

  11. Tanshinone IIA decreases the levels of inflammation induced by Aβ1-42 in brain tissues of Alzheimer's disease model rats.

    Science.gov (United States)

    Lu, Bei-Ling; Li, Jian; Zhou, Jun; Li, Wen-Wen; Wu, Heng-Fei

    2016-08-17

    To study the pathogenesis of Alzheimer's disease (AD) and explore the possible anti-inflammatory mechanism of tanshinone IIA (TanIIA), we evaluated the quantity of neurons and the expression levels of interleukin-1β (IL-1β), IL-6, glial fibrillary acidic protein, CD11b, C1q, C3c, and C3d in brain tissues of AD rats treated with TanIIA. Thirty male Sprague-Dawley rats were randomized into three groups: sham group, TanIIA treatment group, and Aβ1-42 group. Aβ1-42 treatment was performed by injecting Aβ into the hippocampus of rats and then tagged position. Brain tissue morphological structure has been observed with HE staining and the staining of exogenously injected Aβ1-42 was observed by immunohistochemistry, which confirms the success of the Aβ1-42 group. After TanIIA treatment, levels of IL-1β, IL-6, glial fibrillary acidic protein, CD11b, C1q, C3c, and C3d were measured in paraffinized brain tissue sections from all groups by immunohistochemistry staining. The results showed that no 6E10 was detected in the control group, and the difference in the expression levels of 6E10 between the Aβ1-42 group and the TanIIA treatment group was not significant (P>0.05), suggesting that both the Aβ1-42 group and the TanIIA treatment group received the same amount of Aβ. The Aβ1-42 group showed a significant increase in the expression levels of inflammatory markers compared with the sham group (Pastrocytes and microglial cells, and induced a partial decrease in complement molecules in the brain of AD rats. These findings suggested that TanIIA may represent a potential therapeutic treatment in neurodegenerative diseases such as AD to support the survival of neurons by reducing expression levels of inflammatory factors. PMID:27348015

  12. Non-perturbative black holes in Type-IIA String Theory versus the No-Hair conjecture

    International Nuclear Information System (INIS)

    We obtain the first black hole solution to Type-IIA String Theory compactified on an arbitrary self-mirror Calabi–Yau manifold in the presence of non-perturbative quantum corrections. Remarkably enough, the solution involves multivalued functions, which could lead to a violation of the No-Hair conjecture. We discuss how String Theory forbids such scenario. However, the possibility still remains open in the context of four-dimensional ungauged Supergravity. (paper)

  13. Enzymatic properties of stingray Dasyatis pastinaca group V, IIA and IB phospholipases A(2): a comparative study.

    Science.gov (United States)

    Ben Bacha, Abir; Abid, Islem; Horchani, Habib; Mejdoub, Hafedh

    2013-11-01

    In the present study, we have purified the group V phospholipase from the heart of cartilaginous fish stingray Dasyatis pastinaca and compared its biochemical properties with group IIA (sPLA2-IIA) and IB (sPLA2-IB) phospholipases previously purified from pancreas and intestine, respectively. Group V phospholipase (sPLA2-V) was purified to homogeneity by heat treatment, ammonium sulphate precipitation and RP-HPLC. The N-terminal sequence of the purified sPLA2-V exhibits a high degree of homology with those of mammal. The enzyme was found to be monomeric with a molecular mass estimation of 14 kDa. The specific activity of the purified enzyme, measured at pH 8 and 37 °C was 52 U/mg. Like sPLA2-IB and sPLA2-IIA, the sPLA2-V is found to be stable between pH 3 and 11 after 30 min of incubation. The purified sPLA2-V retained 65% of its activity after 10 min of incubation at 70 °C and it absolutely requires Ca(2+) for enzymatic activity. In addition it displayed high tolerance to organic solvents. Kinetic parameters Kmapp, kcat and the deduced catalytic efficiency (kcat/Kmapp) of the purified group-V, -IB and -IIA PLA2s were determined using phosphatidylethanolamine (PE), phosphatidylcholine (PC) or phosphatidylserine (PS) as substrate. The three enzymes hydrolyze the zwiterionic PE and PC substrates more efficiently than anionic PS substrate. PMID:24120965

  14. Value of diffusion-weighted imaging in predicting parametrial invasion in stage IA2-IIA cervical cancer

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jung Jae; Kim, Chan Kyo; Park, Sung Yoon; Park, Byung Kwan [Sungkyunkwan University School of Medicine, Department of Radiology and Center for Imaging Science, Samsung Medical Center, Seoul (Korea, Republic of); Kim, Bohyun [Mayo Clinic College of Medicine, Department of Radiology, Rochester, MN (United States)

    2014-05-15

    To investigate the value of diffusion-weighted imaging (DWI) in evaluating parametrial invasion (PMI) in stage IA2-IIA cervical cancer. A total of 117 patients with stage IA2-IIA cervical cancer who underwent preoperative MRI and radical hysterectomy were included in this study. Preoperative clinical variables and MRI variables were analysed and compared between the groups with and without pathologically proven PMI. All variables except age were significantly different between patients with and without pathologic PMI (P < 0.05). All variables except squamous cell carcinoma (SCC) antigen were also significantly correlated with pathologic PMI on univariate analysis (P < 0.05). Multivariate analysis indicated that PMI on MRI (P < 0.001) and tumour apparent diffusion coefficient (ADC) (P = 0.029) were independent predictors of pathologic PMI. Area under the curve of PMI on MRI increased significantly from 0.793 to 0.872 when combined with tumour ADC (P = 0.002). When PMI on MRI was further stratified by tumour ADC, the false negative rate was 2.0 % (1/49). In stage IA2-IIA cervical cancer, tumour ADC and PMI on MRI seem to be independent predictors of pathologic PMI. Combining the two predictors improved the diagnostic performance of identifying patients at low risk of pathologic PMI. (orig.)

  15. The activity of the lactose transporter from Streptococcus thermophilus is increased by phosphorylated IIA and the action of beta-galactosidase.

    Science.gov (United States)

    Geertsma, Eric R; Duurkens, Ria H; Poolman, Bert

    2005-12-01

    The metabolism of lactose by Streptococcus thermophilus is highly regulated, allowing the bacterium to prefer lactose over glucose as main source of carbon and energy. In vitro analysis of the enzymes involved in transport and hydrolysis of lactose showed that the transport reaction benefits from the hydrolysis of lactose at the trans side of the membrane. Furthermore, the activity of LacS is modulated by PEP-dependent phosphorylation of the IIA domain via the general energy coupling proteins of the PTS, Enzyme I and HPr. To determine whether unphosphorylated LacS-IIA inhibited, or the phosphorylated form stimulated lactose counterflow, a LacS-IIA truncation mutant of LacS was constructed. Detailed analyses of transport in whole cells and in proteoliposomes indicated that unphosphorylated LacS-IIA does not functionally interact with the carrier domain. Instead, interaction of the phosphorylated form of LacS-IIA with the carrier stimulates lactose counterflow transport. The proposed mode of regulation thus proceeds via a mechanism opposite to the inducer exclusion type of regulation in gram-negative bacteria, where transporters are inhibited by binding of the unphosphorylated form of IIA(Glc). PMID:16313191

  16. Myosin IIA participates in docking of Glut4 storage vesicles with the plasma membrane in 3T3-L1 adipocytes

    International Nuclear Information System (INIS)

    In adipocytes and myocytes, insulin stimulation translocates glucose transporter 4 (Glut4) storage vesicles (GSVs) from their intracellular storage sites to the plasma membrane (PM) where they dock with the PM. Then, Glut4 is inserted into the PM and initiates glucose uptake into these cells. Previous studies using chemical inhibitors demonstrated that myosin II participates in fusion of GSVs and the PM and increase in the intrinsic activity of Glut4. In this study, the effect of myosin IIA on GSV trafficking was examined by knocking down myosin IIA expression. Myosin IIA knockdown decreased both glucose uptake and exposures of myc-tagged Glut4 to the cell surface in insulin-stimulated cells, but did not affect insulin signal transduction. Interestingly, myosin IIA knockdown failed to decrease insulin-dependent trafficking of Glut4 to the PM. Moreover, in myosin IIA knockdown cells, insulin-stimulated binding of GSV SNARE protein, vesicle-associated membrane protein 2 (VAMP2) to PM SNARE protein, syntaxin 4 was inhibited. These data suggest that myosin IIA plays a role in insulin-stimulated docking of GSVs to the PM in 3T3-L1 adipocytes through SNARE complex formation.

  17. ART CCIM Phase II-A Off-Gas System Evaluation Test Plan

    Energy Technology Data Exchange (ETDEWEB)

    Nick Soelberg; Jay Roach

    2009-01-01

    This test plan defines testing to be performed using the Idaho National Laboratory (INL) engineering-scale cold crucible induction melter (CCIM) test system for Phase II-A of the Advanced Remediation Technologies (ART) CCIM Project. The multi-phase ART-CCIM Project is developing a conceptual design for replacing the joule-heated melter (JHM) used to treat high level waste (HLW) in the Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS) with a cold crucible induction melter. The INL CCIM test system includes all feed, melter off-gas control, and process control subsystems needed for fully integrated operation and testing. Testing will include operation of the melter system while feeding a non-radioactive slurry mixture prepared to simulate the same type of waste feed presently being processed in the DWPF. Process monitoring and sample collection and analysis will be used to characterize the off-gas composition and properties, and to show the fate of feed constituents, to provide data that shows how the CCIM retrofit conceptual design can operate with the existing DWPF off-gas control system.

  18. Evidence for the Holographic dual of ${\\cal N}=3$ Solution in Massive Type IIA

    CERN Document Server

    Pang, Yi

    2015-01-01

    We calculate the Kaluza-Klein spectrum of spin-2 fluctuations around the ${\\cal N}=3$ warped ${\\rm AdS}_4\\times M_6$ solution in massive IIA supergravity. This solution was conjectured to be dual to the $D=3$ ${\\cal N}=3$ superconformal ${\\rm SU}(N)$ Chern-Simons matter theory with level $k$ and 2 adjoint chiral multiplets. The ${\\rm SO}(3)_R\\times{\\rm SO}(3)_D$ isometry of the ${\\cal N}=3$ solution is identified with the ${\\rm SU}(2)_F\\times {\\rm SU}(2)_{\\cal R}$ global symmetry of the dual ${\\cal N}=3$ SCFT. We show that the ${\\rm SO}(3)_R\\times{\\rm SO}(3)_D$ quantum numbers and the ${\\rm AdS}$ energies carried by the BPS spin-2 modes match precisely with those of the spin-2 gauge invariant operators in the short multiplets of operators in the ${\\cal N}=3$ SCFT. We also compute the Euclidean action of the ${\\cal N}=3$ solution and the free energy of the ${\\cal N}=3$ SCFT on $S^3$, in the limit $N\\gg k$. Remarkably, the results show a complete agreement.

  19. Fluxes, moduli fixing and MSSM-like vacua in a simple IIA orientifold

    CERN Document Server

    Camara, P G; Ibáñez, L E

    2005-01-01

    We study the effects of adding RR, NS and metric fluxes on a T^6/(\\Omega (-1)^{F_L} I_3) Type IIA orientifold. By using the effective flux-induced superpotential we obtain Minkowski or AdS vacua with broken or unbroken supersymmetry. In the Minkowski case some combinations of real moduli remain undetermined, whereas all can be stabilized in the AdS solutions. Many flux parameters are available which are unconstrained by RR tadpole cancellation conditions allowing to locate the minima at large volume and small dilaton. We also find that in AdS supersymmetric vacua with metric fluxes, the overall flux contribution to RR tadpoles can vanish or have opposite sign to that of D6-branes, allowing for new model-building possibilities. In particular, we construct the first N=1 supersymmetric intersecting D6-brane models with MSSM-like spectrum and with all closed string moduli stabilized. Some axion-like fields remain undetermined but they are precisely required to give St\\"uckelberg masses to (potentially anomalous) ...

  20. Engineering of Quantum Hall Effect from Type IIA String Theory on The K3 Surface

    CERN Document Server

    Belhaj, Adil

    2010-01-01

    Using D-brane configurations on the K3 surface, we give six dimensional type IIA stringy realizations of the Quantum Hall Effect (QHE) in 1+2 dimensions. Based on the vertical and horizontal lines of the K3 Hodge diamond, we engineer two different stringy realizations. The vertical line presents a realization in terms of D2 and D6-branes wrapping the K3 surface. The horizontal one is associated with hierarchical stringy descriptions obtained from a quiver gauge theory living on a stack of D4-branes wrapping intersecting 2-spheres embedded in the K3 surface with deformed singularities. These geometries are classified by three kinds of the Kac-Moody algebras: ordinary, i.e finite dimensional, affine and indefinite. We find that no stringy QHE in 1+2 dimensions can occur in the quiver gauge theory living on intersecting 2-spheres arranged as affine Dynkin diagrams. Stringy realizations of QHE can be done only for the finite and indefinite geometries. In particular, the finite Lie algebras give models with fracti...

  1. Fc gamma receptor IIa (CD32) polymorphism in fulminant meningococcal septic shock in children.

    Science.gov (United States)

    Bredius, R G; Derkx, B H; Fijen, C A; de Wit, T P; de Haas, M; Weening, R S; van de Winkel, J G; Out, T A

    1994-10-01

    Antibodies are essential in host defense against Neisseria meningitidis. Therefore, interactions among IgG and Fc receptors (Fc gamma R) on phagocytes may be crucial. Genetic polymorphic forms of Fc gamma RIIa (CD32) express different functional activities. In a retrospective study, Fc gamma R polymorphisms were determined in 25 children who survived fulminant meningococcal septic shock: 11 had Fc gamma RIIa-R/R131, the poor IgG2-binding allotype, which is a significantly more frequent rate than found in a healthy white population (44% vs. 23%; P = .028; odds ratio = 2.67; 95% confidence interval, 1.09-6.53). The relevance of this finding was further supported by the fact that neutrophils with the Fc gamma RIIa-R/R131 allotype phagocytized N. meningitidis opsonized with polyclonal IgG2 antibodies less effectively than did IIa-H/H131 neutrophils. Our findings suggest an important role for anti-N. meningitidis IgG2 and the Fc gamma RIIa polymorphism in host defense against systemic meningococcal infections. PMID:7930726

  2. A Review on Some Chemical Engineering and Microbiological Aspects Considered in the Production of Highly Concentrated Probiotic Cultures and Bacteriocins by Lactococci and Lactobacilli

    OpenAIRE

    Nelson Pérez Guerra

    2012-01-01

    The main purpose of this work is to give an overview on the chemical engineering aspects related with the production of probiotic cultures and bacteriocins. Firstly, some evidence of the potential of different Lactococci and Lactobacilli strains for prevention or treatment of different human diseases, or as growth promoters in farm animals is given. In addition, examples of different commercial dietary supplements containing probiotic lactoccocci and lactobacilli in combination or not with ot...

  3. Genomic and Proteomic Characterization of Bacteriocin-Producing Leuconostoc mesenteroides Strains Isolated from Raw Camel Milk in Two Southwest Algerian Arid Zones

    OpenAIRE

    Zineb Benmechernene; Inmaculada Fernández-No; Marcos Quintela-Baluja; Karola Böhme; Mebrouk Kihal; Pilar Calo-Mata; Jorge Barros-Velázquez

    2014-01-01

    Information on the microbiology of camel milk is very limited. In this work, the genetic characterization and proteomic identification of 13 putative producing bacteriocin Leuconostoc strains exhibiting antilisterial activity and isolated from camel milk were performed. DNA sequencing of the 13 selected strains revealed high homology among the 16S rRNA genes for all strains. In addition, 99% homology with Leuconostoc mesenteroides was observed when these sequences were analysed by the BLAST t...

  4. Inhibition of Listeria monocytogenes in Hot Dogs by Surface Application of Freeze-Dried Bacteriocin-Containing Powders from Lactic Acid Bacteria.

    Science.gov (United States)

    Ünlü, Gülhan; Nielsen, Barbara; Ionita, Claudia

    2016-06-01

    Six lactic acid bacteria (LAB) strains, Lactococcus lactis BFE 920, L. lactis subsp. lactis ATCC 11454, L. lactis subsp. cremoris ATCC 14365, Lactobacillus curvatus L442, Lact. curvatus LTH 1174, and Lact. bavaricus MN, were grown in cheddar cheese whey supplemented with complex nutrient sources. Cell-free culture supernatants were freeze-dried, and the resulting bacteriocin-containing powders were applied on the surface of hot dogs that were inoculated (~4 log cfu/hot dog) with a five-strain Listeria monocytogenes cocktail. Hot dogs were vacuum-sealed and stored at 4 °C for 4 weeks. L. monocytogenes was enumerated, using both tryptic soy agar (TSA) and oxford listeria agar (OXA), on day 0 and at 1, 2, 3, and 4 weeks of the refrigerated storage. In hot dogs containing only the L. monocytogenes inoculum, L. monocytogenes counts increased from 4 up to 7 log cfu/hot dog. All samples containing freeze-dried bacteriocin-containing powders exhibited significantly lowered (P < 0.05) L. monocytogenes populations on the surface of hot dogs throughout the 4-week study except for bavaricin MN powder. Bacterial counts on hot dogs packed without any powder were statistically equal on day 0 when enumerated on OXA. Freeze-dried bacteriocin-containing powders from Lact. curvatus L442 and L. lactis subsp. cremoris ATCC 14365 decreased L. monocytogenes populations on the surface of hot dogs by greater than 2 log cfu/hot dog throughout the 4-week study. For the powdered bacteriocin preparations from L. lactis BFE 920, L. lactis subsp. lactis ATCC 11454, and Lact. curvatus LTH 1174, L. monocytogenes populations were determined to be approximately 3-log cfu/hot dog after 4 weeks of storage. PMID:27094263

  5. Modeling growth and bacteriocin production by Lactobacillus amylovorus DCE 471 in response to temperature and pH values used for sourdough fermentations.

    Science.gov (United States)

    Messens, Winy; Neysens, Patricia; Vansieleghem, Wim; Vanderhoeven, Johan; De Vuyst, Luc

    2002-03-01

    The biokinetics of cell growth of Lactobacillus amylovorus DCE 471 and bacteriocin production by this strain were investigated as a function of the temperatures (28 to 44C) and pH values (pH 4.2 to 6.4) that are characteristic of a sourdough fermentation process. The influence of temperature and pH on microbial behavior is described by using a successfully validated predictive model. PMID:11872497

  6. Modeling Growth and Bacteriocin Production by Lactobacillus amylovorus DCE 471 in Response to Temperature and pH Values Used for Sourdough Fermentations

    OpenAIRE

    Messens, Winy; Neysens, Patricia; Vansieleghem, Wim; Vanderhoeven, Johan; De Vuyst, Luc

    2002-01-01

    The biokinetics of cell growth of Lactobacillus amylovorus DCE 471 and bacteriocin production by this strain were investigated as a function of the temperatures (28 to 44°C) and pH values (pH 4.2 to 6.4) that are characteristic of a sourdough fermentation process. The influence of temperature and pH on microbial behavior is described by using a successfully validated predictive model.

  7. Characterization of bacteriocins produced by Lactococcus lactis strains Caracterização de bacteriocinas produzidas por linhagens de Lactococcus lactis

    Directory of Open Access Journals (Sweden)

    Izildinha Moreno

    2000-09-01

    Full Text Available Bacteriocins produced by fifteen strains of Lactococcus lactis (14 L. lactis subsp. lactis and one L. lactis subsp. cremoris were heat resistant, sensitive to several proteolytic enzymes and active over a wide range of pH. Their resistance to the heating was greatly influenced by the pH. Only the strain L. lactis subsp. lactis ITAL 383 produced a bacteriocin with a wide activity spectrum, similar to nisin of L. lactis subsp. lactis ATCC 11454. This bacteriocin inhibited closely related species and other Gram-positive microorganisms including Listeria monocytogenes and Staphylococcus aureus, but it was not active against the Gram-negative bacteria tested. The identification of partially purified antimicrobial compounds by SDS-PAGE showed that bacteriocin produced by strain ITAL 383 had the same molecular weight of nisin produced by L. lactis subsp. lactis ATCC 11454.Bacteriocinas resistentes ao aquecimento produzidas por quinze linhagens de Lactococcus lactis (14 L. lactis subsp. lactis e 1 L. lactis subsp. cremoris foram sensíveis à enzimas proteolíticas e ativas em uma ampla faixa de pH. A resistência dessas bacteriocinas ao aquecimento foi fortemente influenciada pelo pH do meio. Somente a linhagem L. lactis subsp. lactis ITAL 383 produziu uma bacteriocina com um amplo espectro de atividade, semelhante ao da nisina de L. lactis subsp. lactis ATCC 11454. Esta bacteriocina inibiu as espécies relacionadas e outros microorganismos gram-positivos, inclusive Listeria monocytogenes e Staphylococcus aureus, mas não as bactérias Gram-negativas examinadas. A identificação do composto antimicrobiano parcialmente purificado por SDS-PAGE revelou um peso molecular similar entre a bacteriocina ITAL 383 e a nisina de L. lactis subsp lactis ATCC 11454.

  8. A Sequential Statistical Approach towards an Optimized Production of a Broad Spectrum Bacteriocin Substance from a Soil Bacterium Bacillus sp. YAS 1 Strain

    Directory of Open Access Journals (Sweden)

    Amira M. Embaby

    2014-01-01

    Full Text Available Bacteriocins, ribosomally synthesized antimicrobial peptides, display potential applications in agriculture, medicine, and industry. The present study highlights integral statistical optimization and partial characterization of a bacteriocin substance from a soil bacterium taxonomically affiliated as Bacillus sp. YAS 1 after biochemical and molecular identifications. A sequential statistical approach (Plackett-Burman and Box-Behnken was employed to optimize bacteriocin (BAC YAS 1 production. Using optimal levels of three key determinants (yeast extract (0.48% (w/v, incubation time (62 hrs, and agitation speed (207 rpm in peptone yeast beef based production medium resulted in 1.6-fold enhancement in BAC YAS 1 level (470 AU/mL arbitrary units against Erwinia amylovora. BAC YAS 1 showed activity over a wide range of pH (1–13 and temperature (45–80°C. A wide spectrum antimicrobial activity of BAC YAS 1 against the human pathogens (Clostridium perfringens, Staphylococcus epidermidis, Campylobacter jejuni, Enterobacter aerogenes, Enterococcus sp., Proteus sp., Klebsiella sp., and Salmonella typhimurium, the plant pathogen (E. amylovora, and the food spoiler (Listeria innocua was demonstrated. On top and above, BAC YAS 1 showed no antimicrobial activity towards lactic acid bacteria (Lactobacillus bulgaricus, L. casei, L. lactis, and L. reuteri. Promising characteristics of BAC YAS 1 prompt its commercialization for efficient utilization in several industries.

  9. Cloning and Expression of Synthetic Genes Encoding the Broad Antimicrobial Spectrum Bacteriocins SRCAM 602, OR-7, E-760, and L-1077, by Recombinant Pichia pastoris

    Directory of Open Access Journals (Sweden)

    Sara Arbulu

    2015-01-01

    Full Text Available We have evaluated the cloning and functional expression of previously described broad antimicrobial spectrum bacteriocins SRCAM 602, OR-7, E-760, and L-1077, by recombinant Pichia pastoris. Synthetic genes, matching the codon usage of P. pastoris, were designed from the known mature amino acid sequence of these bacteriocins and cloned into the protein expression vector pPICZαA. The recombinant derived plasmids were linearized and transformed into competent P. pastoris X-33, and the presence of integrated plasmids into the transformed cells was confirmed by PCR and sequencing of the inserts. The antimicrobial activity, expected in supernatants of the recombinant P. pastoris producers, was purified using a multistep chromatographic procedure including ammonium sulfate precipitation, desalting by gel filtration, cation exchange-, hydrophobic interaction-, and reverse phase-chromatography (RP-FPLC. However, a measurable antimicrobial activity was only detected after the hydrophobic interaction and RP-FPLC steps of the purified supernatants. MALDI-TOF MS analysis of the antimicrobial fractions eluted from RP-FPLC revealed the existence of peptide fragments of lower and higher molecular mass than expected. MALDI-TOF/TOF MS analysis of selected peptides from eluted RP-FPLC samples with antimicrobial activity indicated the presence of peptide fragments not related to the amino acid sequence of the cloned bacteriocins.

  10. Characterization and purification of a bacteriocin from Lactobacillus paracasei subsp. paracasei BMK2005, an intestinal isolate active against multidrug-resistant pathogens.

    Science.gov (United States)

    Bendjeddou, Kamel; Fons, Michel; Strocker, Pierre; Sadoun, Djamila

    2012-04-01

    A strain of Lactobacillus paracasei subsp. paracasei BMK2005 isolated from healthy infant faeces has shown a remarkable antibacterial activity against 32 bacterial pathogenic strains of human clinical isolates. Among them, 13 strains belonging to species of Escherichia coli, Citrobacter freundii, Citrobacter diversus, Klebsiella oxytoca, Enterobacter cloacae and Pseudomonas aeruginosa were resistant to Cefotaxime (CTX) and Ceftazidime (CAZ), and 4 strains of Staphylococcus aureus were resistant to Methicillin (MRSA). This antibacterial activity was attributed to a bacteriocin designated as Paracaseicin A. It was heat-stable up to 120°C for 5 min and active within the pH range of 2-5. Its activity was lost when treated with proteases, which reveals its proteinaceous nature. This bacteriocin was successfully purified only by two steps of reversed phase chromatography. Its molecular mass, determined by mass spectrometry analysis, was 2,462.5 Da. To our knowledge, the present study is the first report on characterization and purification of a bacteriocin, produced by a L. paracasei subsp. paracasei strain exhibiting an antibacterial activity against various multidrug-resistant species of Gram-positive and Gram-negative bacteria, which reveals its potential for use in prevention or treatment of infections caused by multidrug-resistant species especially in cases of antibiotics-associated diarrhea (AAD). PMID:22805936

  11. Identification and partial characterization of a bacteriocin-like inhibitory substance (BLIS) from Lb. Bulgaricus K41 isolated from indigenous yogurts.

    Science.gov (United States)

    Zaeim, Davood; Soleimanian-Zad, Sabihe; Sheikh-Zeinoddin, Mahmoud

    2014-01-01

    Forty-two strains of Lactobacillus bulgaricus isolated from locally made yogurts were examined and compared for bacteriocin producing ability using spot on lawn assay which improved by taking photo and image processing. Lb. bulgaricus K41 exhibited the highest inhibition level against indicators. K41 Bacteriocin-like inhibitory substance is sensitive to proteolytic enzymes (proteinase K, pepsin, and trypsin) but α-amylase makes slight reduction in its activity and it is resistant to lipase. This antibacterial peptide is extremely heat-stable (121 °C for 15 min) and remains active over a wide pH range (pH = 2 to 10); also nonionic detergents (Tween-20, Tween-80, and Triton X100) showed no effect on its activity. The inhibitory spectrum is against Gram-positive bacteria (except Staphylococcus aureus) with extremely antilisterial activity and it is almost ineffective against Gram-negative bacteria. The mode of its action was identified as bactericidal against Listeria monocytogenes. The properties of K41 bacteriocin-like inhibitory substance add to its safety as a biopreservative produced by a generally recognized as safe (GRAS) bacterium suggesting it can be used in hurdle technology for ready-to-eat foods as one of the main sources of Listeria contaminations. PMID:24279356

  12. Interaction of c-Cbl with myosin IIA regulates Bleb associated macropinocytosis of Kaposi's sarcoma-associated herpesvirus.

    Directory of Open Access Journals (Sweden)

    Mohanan Valiya Veettil

    Full Text Available KSHV is etiologically associated with Kaposi's sarcoma (KS, an angioproliferative endothelial cell malignancy. Macropinocytosis is the predominant mode of in vitro entry of KSHV into its natural target cells, human dermal microvascular endothelial (HMVEC-d cells. Although macropinocytosis is known to be a major route of entry for many viruses, the molecule(s involved in the recruitment and integration of signaling early during macropinosome formation is less well studied. Here we demonstrate that tyrosine phosphorylation of the adaptor protein c-Cbl is required for KSHV induced membrane blebbing and macropinocytosis. KSHV induced the tyrosine phosphorylation of c-Cbl as early as 1 min post-infection and was recruited to the sites of bleb formation. Infection also led to an increase in the interaction of c-Cbl with PI3-K p85 in a time dependent manner. c-Cbl shRNA decreased the formation of KSHV induced membrane blebs and macropinocytosis as well as virus entry. Immunoprecipitation of c-Cbl followed by mass spectrometry identified the interaction of c-Cbl with a novel molecular partner, non-muscle myosin heavy chain IIA (myosin IIA, in bleb associated macropinocytosis. Phosphorylated c-Cbl colocalized with phospho-myosin light chain II in the interior of blebs of infected cells and this interaction was abolished by c-Cbl shRNA. Studies with the myosin II inhibitor blebbistatin demonstrated that myosin IIA is a biologically significant component of the c-Cbl signaling pathway and c-Cbl plays a new role in the recruitment of myosin IIA to the blebs during KSHV infection. Myosin II associates with actin in KSHV induced blebs and the absence of actin and myosin ubiquitination in c-Cbl ShRNA cells suggested that c-Cbl is also responsible for the ubiquitination of these proteins in the infected cells. This is the first study demonstrating the role of c-Cbl in viral entry as well as macropinocytosis, and provides the evidence that a signaling complex

  13. Class distinction

    Science.gov (United States)

    White, M. Catherine

    Typical 101 courses discourage many students from pursuing higher level science and math courses. Introductory classes in science and math serve largely as a filter, screening out all but the most promising students, and leaving the majority of college graduates—including most prospective teachers—with little understanding of how science works, according to a study conducted for the National Science Foundation. Because few teachers, particularly at the elementary level, experience any collegiate science teaching that stresses skills of inquiry and investigation, they simply never learn to use those methods in their teaching, the report states.

  14. Secreted phospholipase A2-IIA-induced a phenotype of activated microglia in BV-2 cells requires epidermal growth factor receptor transactivation and proHB-EGF shedding

    Directory of Open Access Journals (Sweden)

    Martín Rubén

    2012-07-01

    Full Text Available Abstract Background Activation of microglia, the primary component of the innate immune response in the brain, is a hallmark of neuroinflammation in neurodegenerative disorders, including Alzheimer’s disease (AD and other pathological conditions such as stroke or CNS infection. In response to a variety of insults, microglial cells produce high levels of inflammatory cytokines that are often involved in neuronal injury, and play an important role in the recognition, engulfment, and clearance of apoptotic cells and/or invading microbes. Secreted phospholipase A2-IIA (sPLA2-IIA, an enzyme that interacts with cells involved in the systemic immune/inflammatory response, has been found up-regulated in the cerebrospinal fluid and brain of AD patients. However, despite several approaches, its functions in mediating CNS inflammation remain unknown. In the present study, the role of sPLA2-IIA was examined by investigating its direct effects on microglial cells. Methods Primary and immortalized microglial cells were stimulated by sPLA2-IIA in order to characterize the cytokine-like actions of the phospholipase. The hallmarks of activated microglia analyzed include: mitogenic response, phagocytic capabilities and induction of inflammatory mediators. In addition, we studied several of the potential molecular mechanisms involved in those events. Results The direct exposure of microglial cells to sPLA2-IIA stimulated, in a time- and dose-dependent manner, their phagocytic and proliferative capabilities. sPLA2-IIA also triggered the synthesis of the inflammatory proteins COX-2 and TNFα. In addition, EGFR phosphorylation and shedding of the membrane-anchored heparin-binding EGF-like growth factor (pro-HB-EGF ectodomain, as well as a rapid activation/phosphorylation of the classical survival proteins ERK, P70S6K and rS6 were induced upon sPLA2-IIA treatment. We further demonstrated that the presence of an EGFR inhibitor (AG1478, a matrix metalloproteinase

  15. Anti-Inflammatory Activity of Tanshinone IIA in LPS-Stimulated RAW264.7 Macrophages via miRNAs and TLR4-NF-κB Pathway.

    Science.gov (United States)

    Fan, Guanwei; Jiang, Xiaorui; Wu, Xiaoyan; Fordjour, Patrick Asare; Miao, Lin; Zhang, Han; Zhu, Yan; Gao, Xiumei

    2016-02-01

    Inflammation is a physiological response to infection or injury and involves the innate and adaptive immune system. Tanshinone IIA (Tan IIA) is a well-known flavonoid that elicits an important therapeutic effect by inhibiting inflammatory response. In this study, we examined whether Tan IIA exerts anti-inflammatory activity and investigated the possible mechanisms, including Toll-like receptor 4 (TLR4)-MyD88-nuclear factor kappa B (NF-κB) signaling pathway and microRNA expression in lipopolysaccharide (LPS)-induced RAW264.7 cells. Tan IIA could attenuate the inflammatory reaction via decreasing cytokine, chemokine, and acute-phase protein production, including GM-CSF, sICAM-1, cxcl-1, MIP-1α, and tumor necrosis factor alpha (TNF-α), analyzed by Proteome profile array in LPS-induced RAW264.7 cells. Concurrently, the messenger RNA (mRNA) expressions of IL-1β, TNF-α, and COX-2 were also significantly reduced by Tan IIA. Additionally, Tan IIA decreased LPS-induced NF-κB activation and downregulated TLR4 and MyD88 protein expression levels. We also observed reduced microRNA-155, miR-147, miR-184, miR-29b, and miR-34c expression levels, while LPS-induced microRNA-105, miR-145a, miR-194, miR-383, miR-132, and miR-451a expression levels were upregulated using microRNA (miRNA) qPCR array. Our results indicate that Tan IIA could exert an anti-inflammatory effect on LPS-induced RAW264.7 cells by decreasing TLR4-MyD88-NF-κB signaling pathway and regulating a series of cytokine production and miRNA expression. PMID:26639663

  16. Adjuvant radiotherapy following radical hysterectomy for patients with stage IB and IIA cervical cancer

    International Nuclear Information System (INIS)

    From 1971 through 1984, 320 women underwent radical hysterectomy as primary therapy of stage IB and IIA cervical cancer. Two hundred forty-eight patients (78%) were treated with surgery alone and 72 patients (22%) received adjuvant postoperative external-beam radiotherapy. Presence of lymph node metastasis, large lesion (greater than 4 cm in diameter), histologic grade, race (noncaucasian), and age (greater than 40 years) were significant poor prognostic factors for the entire group of patients. Patients treated with surgery alone had a better disease-free survival than those who received combination therapy (P less than 0.001). However, patients receiving adjuvant radiation therapy had a higher incidence of lymphatic metastases, tumor involvement of the surgical margin, and large cervical lesions. Adjuvant pelvic radiation therapy did not improve the survival of patients with unilateral nodal metastases or those who had a large cervical lesion with free surgical margins and the absence of nodal involvement. Radiation therapy appears to reduce the incidence of pelvic recurrences. Unfortunately, 84% of patients who developed recurrent tumor after combination therapy had a component of distant failure. The incidence of severe gastrointestinal or genitourinary tract complications was not different in the two treatment groups. However, the incidence of lymphedema was increased in patients who received adjuvant radiation therapy. Although adjuvant radiation therapy appears to be tolerated without a significant increase in serious complications, the extent to which it may improve local control rates and survival in high-risk patients appears to be limited. In view of the high incidence of distant metastases in high-risk patients, consideration should be given to adjuvant systemic chemotherapy in addition to radiation therapy

  17. Adjuvant radiotherapy following radical hysterectomy for patients with stage IB and IIA cervical cancer

    Energy Technology Data Exchange (ETDEWEB)

    Soisson, A.P.; Soper, J.T.; Clarke-Pearson, D.L.; Berchuck, A.; Montana, G.; Creasman, W.T. (Duke Univ. Medical Center, Durham, NC (USA))

    1990-06-01

    From 1971 through 1984, 320 women underwent radical hysterectomy as primary therapy of stage IB and IIA cervical cancer. Two hundred forty-eight patients (78%) were treated with surgery alone and 72 patients (22%) received adjuvant postoperative external-beam radiotherapy. Presence of lymph node metastasis, large lesion (greater than 4 cm in diameter), histologic grade, race (noncaucasian), and age (greater than 40 years) were significant poor prognostic factors for the entire group of patients. Patients treated with surgery alone had a better disease-free survival than those who received combination therapy (P less than 0.001). However, patients receiving adjuvant radiation therapy had a higher incidence of lymphatic metastases, tumor involvement of the surgical margin, and large cervical lesions. Adjuvant pelvic radiation therapy did not improve the survival of patients with unilateral nodal metastases or those who had a large cervical lesion with free surgical margins and the absence of nodal involvement. Radiation therapy appears to reduce the incidence of pelvic recurrences. Unfortunately, 84% of patients who developed recurrent tumor after combination therapy had a component of distant failure. The incidence of severe gastrointestinal or genitourinary tract complications was not different in the two treatment groups. However, the incidence of lymphedema was increased in patients who received adjuvant radiation therapy. Although adjuvant radiation therapy appears to be tolerated without a significant increase in serious complications, the extent to which it may improve local control rates and survival in high-risk patients appears to be limited. In view of the high incidence of distant metastases in high-risk patients, consideration should be given to adjuvant systemic chemotherapy in addition to radiation therapy.

  18. Inhibition of Bacillus cereus growth by bacteriocin producing Bacillus subtilis isolated from fermented baobab seeds (maari) is substrate dependent.

    Science.gov (United States)

    Kaboré, Donatien; Nielsen, Dennis Sandris; Sawadogo-Lingani, Hagrétou; Diawara, Bréhima; Dicko, Mamoudou Hama; Jakobsen, Mogens; Thorsen, Line

    2013-03-01

    Maari is a spontaneously alkaline fermented food condiment made from baobab tree seeds. Due to the spontaneous nature of maari fermentations growth of the opportunistic human pathogen Bacillus cereus is occasionally observed. Bacillus subtilis strains are important for alkaline seed fermentations because of their enzymatic activities contributing to desirable texture, flavor and pH development. Some B. subtilis strains have antimicrobial properties against B. cereus. In the present work, three bacteriocin producing B. subtilis strains (B3, B122 and B222) isolated from maari were tested. The production of antimicrobial activity by the three strains was found to be greatly influenced by the substrate. All three B. subtilis strains produced antimicrobial activity against B. cereus NVH391-98 in BHI broth as determined by the agar well diffusion assay, whereas no antimicrobial activity was detected in whole cooked baobab seeds and in 10% (w/v) grinded baobab seeds. Incorporation of BHI with up to 5% (w/w) grinded baobab seeds enhanced the antimicrobial activity of B. subtilis compared with pure BHI in a strain dependent manner. Incorporation of BHI with 50% (w/w) baobab grinded seeds decreased the antimicrobial activity. Addition of the inorganic salts FeCl₃, MgSO₄ and MnSO₄ has previously been reported to increase bacteriocin production of B. subtilis, but the addition of these salts to 10% (w/v) grinded baobab seed broth did not cause antimicrobial activity. Survival of B. cereus NVH391-98 in co-culture with B. subtilis was tested in BHI broth, 10% (w/v) grinded baobab seed based broth and during baobab seed fermentation to produce maari. B. cereus NVH391-98 grew well in all three substrates in mono-culture. All the 3 B. subtilis strains were able to decrease B. cereus NVH391-98 to levels below the detection limit (starter culture candidates originating from maari which are able to prevent pathogen outgrowth remain to be identified. PMID:23376785

  19. CD64 and Group II Secretory Phospholipase A2 (sPLA2-IIA) as Biomarkers for Distinguishing Adult Sepsis and Bacterial Infections in the Emergency Department

    Science.gov (United States)

    Tan, Toh Leong; Ahmad, Nurul Saadah; Nasuruddin, Dian Nasriana; Ithnin, Azlin; Tajul Arifin, Khaizurin; Zaini, Ida Zarina; Wan Ngah, Wan Zurinah

    2016-01-01

    Introduction Early diagnosis of sepsis and bacterial infection is imperative as treatment relies on early antibiotic administration. There is a need to develop new biomarkers to detect patients with sepsis and bacterial infection as early as possible, thereby enabling prompt antibiotic treatment and improving the survival rate. Methods Fifty-one adult patients with suspected bacterial sepsis on admission to the Emergency Department (ED) of a teaching hospital were included into the study. All relevant cultures and serology tests were performed. Serum levels for Group II Secretory Phospholipase A2 (sPLA2-IIA) and CD64 were subsequently analyzed. Results and Discussion Sepsis was confirmed in 42 patients from a total of 51 recruited subjects. Twenty-one patients had culture-confirmed bacterial infections. Both biomarkers were shown to be good in distinguishing sepsis from non-sepsis groups. CD64 and sPLA2-IIA also demonstrated a strong correlation with early sepsis diagnosis in adults. The area under the curve (AUC) of both Receiver Operating Characteristic curves showed that sPLA2-IIA was better than CD64 (AUC = 0.93, 95% confidence interval (CI) = 0.83–0.97 and AUC = 0.88, 95% CI = 0.82–0.99, respectively). The optimum cutoff value was 2.13μg/l for sPLA2-IIA (sensitivity = 91%, specificity = 78%) and 45 antigen bound cell (abc) for CD64 (sensitivity = 81%, specificity = 89%). In diagnosing bacterial infections, sPLA2-IIA showed superiority over CD64 (AUC = 0.97, 95% CI = 0.85–0.96, and AUC = 0.95, 95% CI = 0.93–1.00, respectively). The optimum cutoff value for bacterial infection was 5.63μg/l for sPLA2-IIA (sensitivity = 94%, specificity = 94%) and 46abc for CD64 (sensitivity = 94%, specificity = 83%). Conclusions sPLA2-IIA showed superior performance in sepsis and bacterial infection diagnosis compared to CD64. sPLA2-IIA appears to be an excellent biomarker for sepsis screening and for diagnosing bacterial infections, whereas CD64 could be used for

  20. Cryptosporidium parvum genotype IIa and Giardia duodenalis assemblage A in Mytilus galloprovincialis on sale at local food markets.

    Science.gov (United States)

    Giangaspero, Annunziata; Papini, Roberto; Marangi, Marianna; Koehler, Anson V; Gasser, Robin B

    2014-02-01

    To date, there has been no study to establish the genotypic or subgenotypic identities of Cryptosporidium and Giardia in edible shellfish. Here, we explored the genetic composition of these protists in Mytilus galloprovincialis (Mediterranean mussel) purchased from three markets in the city of Foggia, Italy, from May to December 2012. Samples from the digestive glands, gills and haemolymph were tested by nested PCR, targeting DNA regions within the 60 kDa glycoprotein (gp60) gene of Cryptosporidium, and the triose-phosphate isomerase (tpi) and β-giardin genes of Giardia. In total, Cryptosporidium and Giardia were detected in 66.7% of mussels (M. galloprovincialis) tested. Cryptosporidium was detected mostly between May and September 2012. Sequencing of amplicons showed that 60% of mussels contained Cryptosporidium parvum genotype IIa (including subgenotypes A15G2R1, IIaA15G2 and IIaA14G3R1), 23.3% Giardia duodenalis assemblage A, and 6.6% had both genetic types. This is the first report of these types in fresh, edible shellfish, particularly the very commonly consumed M. galloprovincialis from highly frequented fish markets. These genetic types of Cryptosporidium and Giardia are known to infect humans and thus likely to represent a significant public health risk. The poor observance of hygiene rules by vendors, coupled to the large numbers of M. galloprovincialis sold and the eating habits of consumers in Italy, call for more effective sanitary measures pertaining to the selling of fresh shellfish in street markets. PMID:24334090

  1. The elusive third subunit IIa of the bacterial B-type oxidases: the enzyme from the hyperthermophile Aquifex aeolicus.

    Directory of Open Access Journals (Sweden)

    Laurence Prunetti

    Full Text Available The reduction of molecular oxygen to water is catalyzed by complicated membrane-bound metallo-enzymes containing variable numbers of subunits, called cytochrome c oxidases or quinol oxidases. We previously described the cytochrome c oxidase II from the hyperthermophilic bacterium Aquifex aeolicus as a ba(3-type two-subunit (subunits I and II enzyme and showed that it is included in a supercomplex involved in the sulfide-oxygen respiration pathway. It belongs to the B-family of the heme-copper oxidases, enzymes that are far less studied than the ones from family A. Here, we describe the presence in this enzyme of an additional transmembrane helix "subunit IIa", which is composed of 41 amino acid residues with a measured molecular mass of 5105 Da. Moreover, we show that subunit II, as expected, is in fact longer than the originally annotated protein (from the genome and contains a transmembrane domain. Using Aquifex aeolicus genomic sequence analyses, N-terminal sequencing, peptide mass fingerprinting and mass spectrometry analysis on entire subunits, we conclude that the B-type enzyme from this bacterium is a three-subunit complex. It is composed of subunit I (encoded by coxA(2 of 59000 Da, subunit II (encoded by coxB(2 of 16700 Da and subunit IIa which contain 12, 1 and 1 transmembrane helices respectively. A structural model indicates that the structural organization of the complex strongly resembles that of the ba(3 cytochrome c oxidase from the bacterium Thermus thermophilus, the IIa helical subunit being structurally the lacking N-terminal transmembrane helix of subunit II present in the A-type oxidases. Analysis of the genomic context of genes encoding oxidases indicates that this third subunit is present in many of the bacterial oxidases from B-family, enzymes that have been described as two-subunit complexes.

  2. A Precision Measurement of the W Boson Mass with 1 Inverse Femtobarn of DZero Run IIa Data

    Energy Technology Data Exchange (ETDEWEB)

    Osta, Jyotsna; /Notre Dame U.

    2009-10-01

    This thesis is a detailed presentation of a precision measurement of the mass of the W boson. It has been obtained by analyzing W {yields} e{nu} decays. The data used for this analysis was collected from 2002 to 2006 with the D0 detector, during Run IIa of the Fermilab Tevatron collider. It corresponds to a total integrated luminosity of 1 fb{sup -1}. With a sample of 499,830 W {yields} e{nu} candidate events, we obtain a mass measurement of M{sub W} = 80.401 {+-} 0.043 GeV. This is the most precise measurement from a single experiment to date.

  3. Fermionic T-duality in massive type IIA supergravity on AdS_{10-k} × M_k

    Science.gov (United States)

    Bakhmatov, Ilya

    2016-04-01

    Fermionic T-duality transformation is studied for supersymmetric solutions of massive type IIA supergravity with the metric AdS_{10-k} × M_k for k=3 and 5. We derive the Killing spinors of these backgrounds and use them as input for the fermionic T-duality transformation. The resulting dual solutions form a large family of supersymmetric deformations of the original solutions by complex valued RR fluxes. We observe that the Romans mass parameter does not change under fermionic T-duaity, and prove its invariance in the k=3 case.

  4. Fermionic T-duality in massive type IIA supergravity on AdS_{10-k} x M_k

    CERN Document Server

    Bakhmatov, Ilya

    2015-01-01

    Fermionic T-duality transformation is studied for the N=1 supersymmetric solutions of massive type IIA supergravity with the metric AdS_{10-k} x M_k for k=3 and 5. We derive the Killing spinors of these backgrounds and use them as an input for the fermionic T-duality transformation. The resulting dual solutions form a large family of supersymmetric deformations of the original solutions by complex valued RR fluxes. We observe that the Romans mass parameter does not change under fermionic T-duaity, and prove its invariance in the k=3 case.

  5. X-Ray Diffraction Structure of a plant Glycosyl Hydrolase family 32 protein: Fructan 1-Exohydrolase IIa of Cichorium intybus

    OpenAIRE

    Verhaest, Maureen; Van den Ende, Wim; Le Roy, Katrien; De Ranter, Camiel; Van Laere, André; Rabijns, Anja

    2005-01-01

    Fructan 1-exohydrolase, an enzyme involved in fructan degradation, belongs to the glycosyl hydrolase family 32. The structure of isoenzyme 1-FEH IIa from Cichorium intybus is described at a resolution of 2.35 Å. The structure consists of an N-terminal fivefold β-propeller domain connected to two C-terminal β-sheets. The putative active site is located entirely in the β-propeller domain and is formed by amino acids which are highly conserved within glycosyl hydrolase family 32. The fructan-bin...

  6. Functional analysis of two PLA2G2A variants associated with secretory phospholipase A2-IIA levels.

    Directory of Open Access Journals (Sweden)

    Holly J Exeter

    Full Text Available BACKGROUND: Secretory phospholipase A2 group IIA (sPLA2-IIA has been identified as a biomarker of atherosclerosis in observational and animal studies. The protein is encoded by the PLA2G2A gene and the aim of this study was to test the functionality of two PLA2G2A non-coding SNPs, rs11573156 C>G and rs3767221 T>G where the rare alleles have been previously associated with higher and lower sPLA2-IIA levels respectively. METHODOLOGY/PRINCIPAL FINDINGS: Luciferase assays, electrophoretic mobility shift assays (EMSA, and RNA expression by RT-PCR were used to examine allelic differences. For rs3767221 the G allele showed ∼55% lower luciferase activity compared to the T allele (T = 62.1 (95% CI 59.1 to 65.1 G = 27.8 (95% CI 25.0 to 30.6, p = 1.22×10⁻³⁵, and stronger EMSA binding of a nuclear protein compared to the T-allele. For rs11573156 C >G there were no luciferase or EMSA allelic differences seen. In lymphocyte cell RNA, from individuals of known rs11573156 genotype, there was no allelic RNA expression difference for exons 5 and 6, but G allele carriers (n = 7 showed a trend to lower exon 1-2 expression compared to CC individuals. To take this further, in the ASAP study (n = 223, an rs11573156 proxy (r² = 0.91 showed ∼25% higher liver expression of PLA2G2A (1.67×10⁻¹⁷ associated with the G allele. However, considering exon specific expression, the association was greatly reduced for exon 2 (4.5×10⁻⁵ compared to exons 3-6 (10⁻¹⁰ to 10⁻²⁰, suggesting rs11573156 G allele-specific exon 2 skipping. CONCLUSION: Both SNPs are functional and provide useful tools for Mendelian Randomisation to determine whether the relationship between sPLA2-IIA and coronary heart disease is causal.

  7. A Precision Measurement of the W Boson Mass with 1 Inverse Femtobarn of DZero Run IIa Data

    Energy Technology Data Exchange (ETDEWEB)

    Osta, Jyotsna [Univ. of Notre Dame, IN (United States)

    2009-12-01

    This thesis is a detailed presentation of a precision measurement of the mass of the W boson. It has been obtained by analyzing W → ev decays. The data used for this analysis was collected from 2002 to 2006 with the D0 detector, during Run IIa of the Fermilab Tevatron collider. It corresponds to a total integrated luminosity of 1 fb-1. With a sample of 499,830 W → ev candidate events, we obtain a mass measurement of MW = 80.401 ± 0.043 GeV. This is the most precise measurement from a single experiment to date.

  8. Isolation and Taxonomic Identity of Bacteriocin-Producing Lactic Acid Bacteria from Retail Foods and Animal Sources

    Directory of Open Access Journals (Sweden)

    Chris Henning

    2015-03-01

    Full Text Available Bacteriocin-producing (Bac+ lactic acid bacteria (LAB were isolated from a variety of food products and animal sources. Samples were enriched in de Man, Rogosa, and Sharpe (MRS Lactocilli broth and plated onto MRS agar plates using a “sandwich overlay” technique. Inhibitory activity was detected by the “deferred antagonism” indicator overlay method using Listeria monocytogenes as the primary indicator organism. Antimicrobial activity against L. monocytogenes was detected by 41 isolates obtained from 23 of 170 food samples (14% and 11 of 110 samples from animal sources (10% tested. Isolated Bac+ LAB included Lactococcus lactis, Lactobacillus curvatus, Carnobacterium maltaromaticum, Leuconostoc mesenteroides, and Pediococcus acidilactici, as well as Enterococcus faecium, Enterococcus faecalis, Enterococcus hirae, and Enterococcus thailandicus. In addition to these, two Gram-negative bacteria were isolated (Serratia plymuthica, and Serratia ficaria that demonstrated inhibitory activity against L. monocytogenes, Staphylococcus aureus, and Enterococcus faecalis (S. ficaria additionally showed activity against Salmonella Typhimurium. These data continue to demonstrate that despite more than a decade of antimicrobial interventions on meats and produce, a wide variety of food products still contain Bac+ microbiota that are likely eaten by consumers and may have application as natural food preservatives.

  9. The streptococcal inhibitor of complement (SIC) protects Streptococcus pyogenes from bacteriocin-like inhibitory substance (BLIS) from Streptococcus salivarius.

    Science.gov (United States)

    Minami, Masaaki; Ohmori, Daisuke; Tatsuno, Ichiro; Isaka, Masanori; Kawamura, Yoshiaki; Ohta, Michio; Hasegawa, Tadao

    2009-09-01

    Streptococcus salivarius inhibits the growth of Streptococcus pyogenes in vitro. Streptococcus pyogenes has various virulence factors, including the streptococcus inhibitor of complement (SIC). Although SIC inhibits the activity of the peptides LL-37 and NAP1, the relationship between SIC and the bacteriocin-like inhibitory substance (BLIS) has not been elucidated. Here, we evaluated whether S. salivarius BLIS affects S. pyogenes SIC. We created three deltasic mutant strains from three S. pyogenes strains and performed deferred antagonism assays. The test strains were BLIS-positive S. salivarius JCM5707 and BLIS-negative S. salivarius NCU12. Deferred antagonism assays with JCM5707 showed that the inhibitory zones in the three deltasic mutant strains were wider than those in the three wild-type strains. Streptococcus pyogenes was cultured in BLIS-containing broth and the change in SIC in the supernatant was assessed by two-dimensional gel electrophoresis (2-DE). The 2-DE analysis of S. pyogenes exoproteins with the JCM5707 supernatant showed reduced SIC compared with those without the JCM5707 supernatant. Changes in sic mRNA levels affected by S. salivarius BLIS were evaluated by a reverse transcriptase-PCR. The sic mRNA level was affected more by the BLIS-positive S. salivarius than by the BLIS-negative strain. Our result indicates that SIC plays a role in the inhibition of S. salivarius BLIS. PMID:19594623

  10. Expression of a novel bacteriocin-the plantaricin Pln1-in Escherichia coli and its functional analysis.

    Science.gov (United States)

    Meng, Fanqiang; Zhao, Haizhen; Zhang, Chong; Lu, Fengxia; Bie, Xiaomei; Lu, Zhaoxin

    2016-03-01

    A potential bacteriocin gene was isolated from 18575 ORFs by bioinformatics methods. It was named pln1, and cloned into pET32a. Then, it was expressed as a thioredoxin-Pln1 fusion protein in Escherichia coli BL21 (DE3). The fusion protein was purified by Ni-NTA, and thioredoxin was removed by enterokinase. Finally, Pln1 was purified using a cation affinity column. The yields of fused and cleaved Pln1 peptides were 100-110 mg/l and 9-11 mg/l, respectively. Pln1 was stable in an acidic environment and at temperatures below 60 °C, but was easily degraded under alkaline conditions and by protease treatment. The cleaved and purified Pln1 showed strong antimicrobial activity against gram-positive bacteria such as Micrococcus luteus CMCC 63202, Staphylococcus epidermidis, Lactococcus lactis NZ3900, Lactobacillus paracasei CICC 20241, and Listeria innocua CICC 10417. In particular, Pln1 had a better activity against methicillin-resistant S. epidermidis (MRSE) than nisin, thereby offering an attractive approach to counter bacterial antibiotic resistance. PMID:26586613

  11. Aqueous two-phase flotation for primary recovery of bacteriocin-like inhibitory substance (BLIS) from Pediococcus acidilactici Kp10.

    Science.gov (United States)

    Md Sidek, Nurul Lyana; Tan, Joo Shun; Abbasiliasi, Sahar; Wong, Fadzlie Wong Faizal; Mustafa, Shuhaimi; Ariff, Arbakariya B

    2016-08-01

    An aqueous two-phase flotation (ATPF) system based on polyethylene glycol (PEG) and sodium citrate (NaNO3C6H5O7·2H2O) was considered for primary recovery of bacteriocin-like inhibitory substance (BLIS) from Pediococcus acidilactici Kp10. The effects of ATPF parameters namely phase composition, tie-line length (TLL), volume ratio between the two phases (VR), amount of crude load (CL), pH, nitrogen gas flow rate (FR) and flotation time (FT) on the performance of recovery were evaluated. BLIS was mainly concentrated into the upper PEG-rich phase in all systems tested so far. The optimum conditions for BLIS purification, which composed of PEG 8000/sodium citrate, were: TLL of 42.6, VR of 0.4, CL of 22% (w/w), pH 7, average FT of 30min and FR of 20mL/min. BLIS was partially purified up to 5.9-fold with a separation efficiency of 99% under this optimal conditions. A maximum yield of BLIS activity of about 70.3% was recovered in the PEG phase. The BLIS from the top phase was successfully recovered with a single band in SDS-gel with molecular weight of about 10-15kDa. ATPF was found to be an effective technique for the recovery of BLIS from the fermentation broth of P. acidilactici Kp10. PMID:27262666

  12. Advanced Start of Combustion Sensor Phases I and II-A: Feasibility Demonstration, Design and Optimization

    Energy Technology Data Exchange (ETDEWEB)

    Chad Smutzer

    2010-01-31

    Homogeneous Compressed Charge Ignition (HCCI) has elevated the need for Start of Combustion (SOC) sensors. HCCI engines have been the exciting focus of engine research recently, primarily because HCCI offers higher thermal efficiency than the conventional Spark Ignition (SI) engines and significantly lower NOx and soot emissions than conventional Compression Ignition (CI) engines, and could be fuel neutral. HCCI has the potential to unify all the internal combustion engine technology to achieve the high-efficiency, low-emission goal. However, these advantages do not come easy. It is well known that the problems encountered with HCCI combustion center on the difficulty of controlling the Start of Combustion. TIAX has an SOC sensor under development which has shown promise. In previous work, including a DOE-sponsored SBIR project, TIAX has developed an accelerometer-based method which was able to determine SOC within a few degrees crank angle for a range of operating conditions. A signal processing protocol allows reconstruction of the combustion pressure event signal imbedded in the background engine vibration recorded by the accelerometer. From this reconstructed pressure trace, an algorithm locates the SOC. This SOC sensor approach is nonintrusive, rugged, and is particularly robust when the pressure event is strong relative to background engine vibration (at medium to high engine load). Phase I of this project refined the previously developed technology with an engine-generic and robust algorithm. The objective of the Phase I research was to answer two fundamental questions: Can the accelerometer-based SOC sensor provide adequate SOC event capture to control an HCCI engine in a feedback loop? And, will the sensor system meet cost, durability, and software efficiency (speed) targets? Based upon the results, the answer to both questions was 'YES'. The objective of Phase II-A was to complete the parameter optimization of the SOC sensor prototype in order

  13. Bacteriocin production by Lactobacillus pentosus ST712BZ isolated from boza Bacteriocina produzida por Lactobacillus pentosus ST712BZ isolad de boza

    Directory of Open Access Journals (Sweden)

    Svetoslav D. Todorov

    2007-03-01

    Full Text Available Bacteriocin ST712BZ (14.0kDa in size inhibits the growth of Lactobacillus casei,Escherichia coli, Pseudomonas aeruginosa,Enterococcus faecalis, Klebsiella pneumoniae and Lactobacillus curvatus. Growth of strain ST712BZ in BHI, M17, soy milk and molasses was similar to growth in MRS, with optimal bacteriocin production (12800AU/mL recorded in MRS after 24h. The same level of bacteriocin production (12800AU/mL was recorded in MRS broth with an initial pH of 6.5, 6.0 and 5.5. However, MRS broth (pH 6.5 supplemented with 1mM EDTA, yielded only 6400AU/mL. Low levels of bacteriocin activity were recorded in MRS broth with an initial pH of 5.0 and 4.5. Of all media compositions tested, MRS supplemented with tryptone (20.0g/L, glucose (20.0 to 40.0g/L, mannose (20.0g/L, vitamin B12, or vitamin C yielded 12800AU/mL. Glycerol concentrations of 1.0g/L and higher repressed bacteriocin production. Maximal bacteriocin activity (25600AU/mL was recorded in MRS supplemented with Vit. B1 or DL-6,8-thioctic acid.A bacteriocina ST712BZ produzida par Lactobacillus pentosus (peso molecular de 14,0kDa inibe o crescimento de Lactobacillus casei,Escherichia coli, Pseudomonas aeruginosa,Enterococcus faecalis, Klebsiella pneumoniae e Lactobacillus curvatus. O crescimento de L. pentosus ST712BZ em BHI, M17, leite de soja e melaços foi semelhante ao observado em MRS, registando-se a produção máxima de bacteriocina (12800UA/mL em MRS após 24 h. Observou-se o mesmo nível de produção de bacteriocina (12800UA/mL em caldo MRS com pH inicial de 6,5, 6,0 e 5,5. No entanto, em caldo MRS (pH 6,5 suplementado com 1 mM de EDTA a produção apenas atingiu 6400UA/mL. Os níveis de atividade bacteriocinogênica detectados em caldo MRS com um pH inicial de 5,0 e 4,5 foram baixos. De todas as fórmulas de meios de cultura testadas a que apresentou a atividade máxima 12800UA/mL foi MRS suplemento de triptona (20,0g/L, glicose (20,0 e 40,0 g/L, manose (20.0 g/L, vitamina B12 e

  14. Glycyrrhetinic acid-decorated and reduction-sensitive micelles to enhance the bioavailability and anti-hepatocellular carcinoma efficacy of tanshinone IIA.

    Science.gov (United States)

    Chen, Fengqian; Zhang, Jinming; He, Yao; Fang, Xiefan; Wang, Yitao; Chen, Meiwan

    2016-01-01

    It remains a challenge to increase drug tumor-specific accumulation as well as to achieve intracellular-controlled drug release for hepatocellular carcinoma (HCC) chemotherapy. Herein, we developed a dual-functional biodegradable micellar system constituted by glycyrrhetinic acid coupling poly(ethylene glycol)-disulfide linkage-poly(lactic-co-glycolic acid) (GA-PEG-SS-PLGA) to achieve both hepatoma-targeting and redox-responsive intracellular drug release. Tanshinone IIA (TAN IIA), an effective anti-HCC drug, was encapsulated. Notably, it exhibited rapid aggregation and faster drug release in 10 mM dithiothreitol compared with the redox-insensitive control. Furthermore, GA-decorated micelles revealed HCC-specific cellular uptake in human liver cancer HepG2 cells with an energy-dependent manner, in which micropinocytosis and caveolae-mediated endocytosis were demonstrated as the major cellular pathways. The enhanced cytotoxicity and pro-apoptotic effects against HepG2 cells in vitro were observed, mediated by up-regulation of the intracellular ROS level, the increased cell cycle arrest at S phase, enhanced necrocytosis and up-regulation of caspase 3/7, P38 protein expression. In addition, TAN IIA-loaded micelles had a significantly prolonged circulation time, improved bioavailability, and resulted in an increased accumulation of TAN IIA in the liver. With the synergistic effects of HCC-targeting and controlled drug release, TAN IIA-loaded GA-PEG-SS-PLGA micelles significantly inhibited tumor growth and increased survival time in a mouse HCC-xenograft model. Collectively, the GA-PEG-SS-PLGA micelles with HCC-targeting and redox-sensitive characters would provide a novel strategy to deliver TAN IIA effectively for HCC therapy. PMID:26484363

  15. Effects of Tanshinone IIA on the modulation of miR-33a and the SREBP-2/Pcsk9 signaling pathway in hyperlipidemic rats

    Science.gov (United States)

    JIA, LIANQUN; SONG, NAN; YANG, GUANLIN; MA, YIXIN; LI, XUETAO; LU, REN; CAO, HUIMIN; ZHANG, NI; ZHU, MEILIN; WANG, JUNYAN; LENG, XUE; CAO, YUAN; DU, YING; XU, YUE

    2016-01-01

    Tanshinone IIA is the active compound isolated from Salvia miltiorrhiza bunge, which is a traditional Chinese medicine known as Danshen. The aim of the present study was to assess the effect of Tanshinone IIA on the regulation of lipid metabolism in the livers of hyperlipidemic rats and the underlying molecular events. An in vivo model of hyperlipidemia was established in rats, with the animals receiving a daily dose of Tanshinone IIA. The serum lipid profiles were analyzed using an automatic biochemical analyzer, and the histopathological alterations and lipid deposition in liver tissue were assessed using hematoxylin and eosin staining, and oil red O staining, respectively. The mRNA expression levels of microRNA (miR)-33a, ATP-binding cassette transporter (ABC)A1, ABCG1, sterol regulatory element-binding protein 2 (SREBP-2), proprotein convertase subtilisin/kexin type 9 (Pcsk9) and low-density lipoprotein receptor (LDL-R) in liver tissues were measured using reverse transcription-quantitative polymerase chain reaction, and the protein expression levels of ABCA1, ABCG1, SREBP-2, Pcsk9, and LDL-R were analyzed using western blotting. Tanshinone IIA reduced lipid deposition and improved histopathology in the rat liver tissue, however, did not alter the lipid profile in rat serum. In addition, Tanshinone IIA treatment suppressed the expression of miR-33a, whereas the protein expression levels of ABCA1, SREBP-2, Pcsk9 in addition to LDL-R mRNA and protein were upregulated. In conclusion, the present study indicated that Tanshinone IIA attenuated lipid deposition in the livers of hyperlipidemic rats and modulated the expression of miR-33a and SREBP-2/Pcsk9 signaling pathway proteins. PMID:27082100

  16. Klotho/fibroblast growth factor 23- and PTH-independent estrogen receptor-α-mediated direct downregulation of NaPi-IIa by estrogen in the mouse kidney.

    Science.gov (United States)

    Webster, Rose; Sheriff, Sulaiman; Faroqui, Rashma; Siddiqui, Faraaz; Hawse, John R; Amlal, Hassane

    2016-08-01

    Estrogen treatment causes renal phosphate (Pi) wasting and hypophosphatemia in rats and humans; however, the signaling mechanisms mediating this effect are still poorly understood. To determine the specific roles of estrogen receptor isoforms (ERα and ERβ) and the Klotho pathway in mediating these effects, we studied the effects of estrogen on renal Pi handling in female mice with null mutations of ERα or ERβ or Klotho and their wild type (WT) using balance studies in metabolic cages. Estrogen treatment of WT and ERβ knockout (KO) mice caused a significant reduction in food intake along with increased renal phosphate wasting. The latter resulted from a significant downregulation of NaPi-IIa and NaPi-IIc protein abundance. The mRNA expression levels of both transporters were unchanged in estrogen-treated mice. These effects on both food intake and renal Pi handling were absent in ERα KO mice. Estrogen treatment of Klotho KO mice or parathyroid hormone (PTH)-depleted thyroparathyroidectomized mice exhibited a significant downregulation of NaPi-IIa with no change in the abundance of NaPi-IIc. Estrogen treatment of a cell line (U20S) stably coexpressing both ERα and ERβ caused a significant downregulation of NaPi-IIa protein when transiently transfected with a plasmid containing full-length or open-reading frame (ORF) 3'-untranslated region (UTR) but not 5'-UTR ORF of mouse NaPi-IIa transcript. In conclusion, estrogen causes phosphaturia and hypophosphatemia in mice. These effects result from downregulation of NaPi-IIa and NaPi-IIc proteins in the proximal tubule through the activation of ERα. The downregulation of NaPi-IIa by estrogen involves 3'-UTR of its mRNA and is independent of Klotho/fibroblast growth factor 23 and PTH signaling pathways. PMID:27194721

  17. Effects of Tanshinone IIA on the modulation of miR‑33a and the SREBP‑2/Pcsk9 signaling pathway in hyperlipidemic rats.

    Science.gov (United States)

    Jia, Lianqun; Song, Nan; Yang, Guanlin; Ma, Yixin; Li, Xuetao; Lu, Ren; Cao, Huimin; Zhang, Ni; Zhu, Meilin; Wang, Junyan; Leng, Xue; Cao, Yuan; Du, Ying; Xu, Yue

    2016-06-01

    Tanshinone IIA is the active compound isolated from Salvia miltiorrhiza bunge, which is a traditional Chinese medicine known as Danshen. The aim of the present study was to assess the effect of Tanshinone IIA on the regulation of lipid metabolism in the livers of hyperlipidemic rats and the underlying molecular events. An in vivo model of hyperlipidemia was established in rats, with the animals receiving a daily dose of Tanshinone IIA. The serum lipid profiles were analyzed using an automatic biochemical analyzer, and the histopathological alterations and lipid deposition in liver tissue were assessed using hematoxylin and eosin staining, and oil red O staining, respectively. The mRNA expression levels of microRNA (miR)‑33a, ATP‑binding cassette transporter (ABC)A1, ABCG1, sterol regulatory element‑binding protein 2 (SREBP‑2), proprotein convertase subtilisin/kexin type 9 (Pcsk9) and low‑density lipoprotein receptor (LDL‑R) in liver tissues were measured using reverse transcription‑quantitative polymerase chain reaction, and the protein expression levels of ABCA1, ABCG1, SREBP‑2, Pcsk9, and LDL‑R were analyzed using western blotting. Tanshinone IIA reduced lipid deposition and improved histopathology in the rat liver tissue, however, did not alter the lipid profile in rat serum. In addition, Tanshinone IIA treatment suppressed the expression of miR‑33a, whereas the protein expression levels of ABCA1, SREBP‑2, Pcsk9 in addition to LDL‑R mRNA and protein were upregulated. In conclusion, the present study indicated that Tanshinone IIA attenuated lipid deposition in the livers of hyperlipidemic rats and modulated the expression of miR‑33a and SREBP‑2/Pcsk9 signaling pathway proteins. PMID:27082100

  18. Flesh or fish? First results of archaeometric research of prehistoric burials from Sakhtysh IIa, Upper Volga region, Russia

    Directory of Open Access Journals (Sweden)

    Henny Piezonka

    2013-12-01

    Full Text Available Graves and their human remains not only shed light on burial customs and social structures of past populations, but also constitute an excellent archive of prehistoric environmental and living conditions. Especially 13C/15N isotope analysis has recently opened up promising perspectives for reconstructing changes in diet and their social, cultural and economic background. Such investigations have been started on material from the Stone and Early Metal Age hunter-gatherer cemetery of Sakhtysh IIa in the Upper Volga region of Central Russia, where 15 burials associated with the early Lyalovo culture (5th mill. calBC and 57 graves of the Volosovo culture (4th – 3rd mill. calBC have been excavated. In this paper, we present new AMS dates and isotopic data from four burials, two from the earlier and two from the later group. The results are discussed against the background of existing dates from Sakhtysh IIa burials and compared with information from other burial sites of Northern Europe.

  19. Radiation in impurity-seeded discharges in the JET MkI, MkIIA and MkIIGB divertors

    International Nuclear Information System (INIS)

    Radiative cooling by seeded impurities is a way to reduce the power load on divertor targets. Impurity-seeding experiments carried out in the JET MkI, MkIIA and MkIIGB divertors are discussed, in particular in terms of their radiative properties. A reassessment of the radiation levels in about 235 discharges, seeded predominantly with nitrogen or neon, leads to the conclusion that radiation levels have been underestimated in some impurity-seeded plasmas in MkI and MkIIA. Apart from increased radiation levels, the consequences of the reassessment for the interpretation of impurity-seeded plasmas are limited. With the new estimates the understanding of the power balance and the fit to Matthews' scaling law for Zeff are improved. The techniques for improved estimates of the total radiated power and radiated power in the divertor region are discussed and it is shown that weighted summation of bolometer line integrals is unreliable for impurity-seeded discharges in JET

  20. The structural, electronic and optical response of IIA-VIA compounds through the modified Becke-Johnson potential

    Science.gov (United States)

    Ali, Roshan; Mohammad, S.; Ullah, Hamid; Khan, S. A.; Uddin, H.; Khan, M.; Khan, N. U.

    2013-02-01

    The structural, electronic and optical properties of IIA-VIA compounds are performed, by using the full-potential linearized augmented plan wave (FP-LAPW) method within DFT, by using the (PBEsol-GGA 2008) version. We have compared the modified Becke-Johnson (mBJ) potential to LDA, GGA and EV-GGA approximations. The IIA-VIA compounds have rock salt structure (B1) and zinc-blend structure (B3). The results obtained for band structure using mBJ show a significant improvement over previous theoretical work and give closer values to the experimental results. The bandgaps less than 3.1 eV are used in the visible light devices applications, while those with bandgaps bigger than 3.1 eV, used in UV devices applications. Optical parameters, like the dielectric constant, refractive indices, reflectivity, optical conductivity and absorption coefficient are calculated and analyzed. Refractive index lesser than unity (vg=c/n) shows that the group velocity of the incident radiation is greater than the speed of light.

  1. Molecular Detection and Sensitivity to Antibiotics and Bacteriocins of Pathogens Isolated from Bovine Mastitis in Family Dairy Herds of Central Mexico

    OpenAIRE

    Ma. Fabiola León-Galván; Barboza-Corona, José E.; A. Arianna Lechuga-Arana; Mauricio Valencia-Posadas; Aguayo, Daniel D.; Carlos Cedillo-Pelaez; Erika A. Martínez-Ortega; Gutierrez-Chavez, Abner J.

    2015-01-01

    Thirty-two farms (n = 535 cows) located in the state of Guanajuato, Mexico, were sampled. Pathogens from bovine subclinical mastitis (SCM) and clinical mastitis (CLM) were identified by 16S rDNA and the sensitivity to both antibiotics and bacteriocins of Bacillus thuringiensis was tested. Forty-six milk samples were selected for their positive California Mastitis Test (CMT) (≥3) and any abnormality in the udder or milk. The frequency of SCM and CLM was 39.1% and 9.3%, respectively. Averages f...

  2. Detection and characterization of bacteriocin-producing Lactococcus lactis strains Detecção e caracterização de Lactococcus lactis produtores de bacteriocinas

    Directory of Open Access Journals (Sweden)

    Izildinha Moreno

    1999-04-01

    Full Text Available One hundred sixty seven strains of Lactococcus lactis were screened for bacteriocin production by well diffusion assay of GM17 agar. Fourteen (8.4% produced antimicrobial activity other than organic acids, bacteriophages or hydrogen peroxide. The frequency of bacteriocin production ranged from 2% in L. lactis subsp. cremoris up to 12% in L. lactis subsp. lactis. Antimicrobial activities were not observed in any strain of L. lactis subsp. lactis var. diacetylactis. Among thirteen bacteriocin-producing strains and two nisin-producing strains (L. lactis subsp. lactis ATCC 11454 and L. lactis subsp. lactis CNRZ 150, eight (53% were characterized as lactose-positive (Lac+ and proteinase-negative (Prt-. The bacteriocin-producing cultures were also characterized on the basis of plasmid content. All strains had 2 to 7 plasmids with molecular weights varying from 0.5 to 28.1 Mdal. Four strains (ITAL 435, ITAL 436, ITAL 437 and ITAL 438 showed identical profiles and the other were quite distinct.Um total de 167 linhagens de L. lactis foi selecionado para os testes de produção de bacteriocinas pelo método de difusão em poços em agar GM17. Desse total, 14 (8.4% produziram substâncias inibidoras que não foram associadas com ácidos orgânicos, peróxido de hidrogênio e bacteriófagos. A frequência de produção de bacteriocinas variou de 2% em L. lactis subsp. cremoris a 12% em L. lactis subsp. lactis. Nenhuma das linhagens de L. lactis subsp. lactis var. diacetylactis produziu substâncias inibidoras. De 13 linhagens produtoras de bacteriocinas e duas de nisina (L. lactis subsp. lactis ATCC 11454 e L. lactis subsp. lactis CNRZ 150, 8 (53% foram caracterizadas como lactose-positivas (Lac+ e proteinase-negativas (Prt-. As linhagens produtoras de bacteriocinas também foram caracterizadas no seu conteúdo de plasmídios. Elas apresentaram de 2 a 7 plasmídios, com pesos moleculares aproximados de 0.5 a 28.1 Mdal. Quatro linhagens (ITAL 435, ITAL 436

  3. In Vitro Detection And Characterization Of Bacteriocin-Like Inhibitory Activity Of Lactic Acid Bacteria (Lab) Isolated From Senegalese Local Food Products

    OpenAIRE

    Diop, Mb.; Dubois Dauphin, Robin; Dortu, C.; Destain, Jacqueline; Tine, E.; Thonart, Philippe

    2008-01-01

    The prevalence of lactic acid bacteria (LAB) in Senegalese local food products was determined to be 109 CFU/g in millet flour and milk products, and 103 CFU/g in seafood products. These food products are generally preserved by spontaneous fermentation (without addition of starters). Of 220 lactic acid bacteria strains randomly selected from such products, 12 isolates capable of producing bacteriocin-like substances (bac+) were detected. Based on the use of API 50 CH test kits and 16S rDNA seq...

  4. On the universality class of certain string theory hadrons

    International Nuclear Information System (INIS)

    Exploiting the gauge/gravity correspondence we d the spectrum of hadronic-like bound states of adjoint particles with a large global charge in several confining theories. In particular, we consider an embedding of four-dimensional N = 1 supersymmetric Yang-Mills into IIA string theory, two classes of three-dimensional gauge theories and the softly broken version of one of them. In all cases we describe the low energy excitations of a heavy hadron with mass proportional to its global charge. These excitations include: the hadron's nonrelativistic motion, its stringy excitations and excitations corresponding to the addition of massive constituents. Our analysis provides ample evidence for the universality of such hadronic states in con ing theories admitting supergravity duals. Besides, we d numerically a new smooth solution that can be thought of as a non-supersymmetric deformation of G2 holonomy manifolds. (author)

  5. Class Vectors: Embedding representation of Document Classes

    OpenAIRE

    Sachan, Devendra Singh; Kumar, Shailesh

    2015-01-01

    Distributed representations of words and paragraphs as semantic embeddings in high dimensional data are used across a number of Natural Language Understanding tasks such as retrieval, translation, and classification. In this work, we propose "Class Vectors" - a framework for learning a vector per class in the same embedding space as the word and paragraph embeddings. Similarity between these class vectors and word vectors are used as features to classify a document to a class. In experiment o...

  6. Teachers in Class

    Science.gov (United States)

    Van Galen, Jane

    2008-01-01

    In this article, I argue for a closer read of the daily "class work" of teachers, as posited by Reay, 1998. In developing exploratory class portraits of four teachers who occupy distinctive social positions (two from working-class homes now teaching upper-middle-class children and two from upper-middle-class homes now teaching poor children), I…

  7. ATP6V0A2 mutations present in two Mexican Mestizo children with an autosomal recessive cutis laxa syndrome type IIA

    Directory of Open Access Journals (Sweden)

    D. Bahena-Bahena

    2014-01-01

    Full Text Available Patients with ARCL-IIA harbor mutations in ATP6V0A2 that codes for an organelle proton pump. The ARCL-IIA syndrome characteristically presents a combined glycosylation defect affecting N-linked and O-linked glycosylations, differentiating it from other cutis laxa syndromes and classifying it as a Congenital Disorder of Glycosylation (ATP6V0A2-CDG. We studied two Mexican Mestizo patients with a clinical phenotype corresponding to an ARCL-IIA syndrome. Both patients presented abnormal transferrin (N-linked glycosylation but Patient 1 had a normal ApoCIII (O-linked glycosylation profile. Mutational screening of ATP6V0A2 using cDNA and genomic DNA revealed in Patient 1 a previously reported homozygous nonsense mutation c.187C>T (p.R63X associated with a novel clinical finding of a VSD. In Patient 2 we found a homozygous c.2293C>T (p.Q765X mutation that had been previously reported but found that it also altered RNA processing generating a novel transcript not previously identified (r.2176_2293del; p.F726Sfs*10. This is the first report to describe Mestizo patients with molecular diagnosis of ARCL-IIA/ATP6V0A2-CDG and to establish that their mutations are the first to be found in patients from different regions of the world and with different genetic backgrounds.

  8. Role of the Fc gamma receptor IIa polymorphism in susceptibility to systemic lupus erythematosus and lupus nephritis - A meta-analysis

    NARCIS (Netherlands)

    Karassa, FB; Trikalinos, TA; Ioannidis, JPA

    2002-01-01

    Objective. To assess the impact of the Fcgamma receptor type IIa (FcgammaRIIa)-R/H131 polymorphism on the risk for systemic lupus erythematosus (SLE) and development of lupus nephritis. Methods. A meta-analysis was performed based on the Medline and Embase databases (last retrieval August 2001), ass

  9. Randomized double-blind controlled Phase I/IIa trial to assess the efficacy of malaria vaccine PfCS102 to protect against challenge with P. falciparum.

    NARCIS (Netherlands)

    Genton, B.; D'Acremont, V.; Lurati-Ruiz, F.; Verhage, D.F.; Audran, R.; Hermsen, C.C.; Wolters, L.; Reymond, C.; Spertini, F.; Sauerwein, R.W.

    2010-01-01

    The aim of this Phase I/IIa double-blind controlled trial was to test the efficacy of the sporozoite-based malaria vaccine PfCS 282-383 (PfCS102) to protect against Plasmodium falciparum parasitaemia. 16 volunteers were randomized to receive twice 30 mug of PfCS102 formulated in Montanide ISA 720 or

  10. Mode of action and in vitro susceptibility of mastitis pathogens to macedocin ST91KM and preparation of a teat seal containing the bacteriocin

    Directory of Open Access Journals (Sweden)

    Renee Pieterse

    2010-03-01

    Full Text Available Mastitis is considered to be the most economically costly disease affecting the dairy industry. Regular dosage of animals with antibiotics, including use of prophylactic concentrations, may select for resistant strains. The purpose of this study was to determine the mode of action of a new bacteriocin (macedocin ST91KM, to evaluate the antimicrobial resistance of mastitis pathogens to antibiotics commonly used in treatment remedies, and to introduce the possible use of an alternative antimicrobial agent. The bacteriocin macedocin ST91KM, produced by Streptococcus gallolyticus subsp. macedonicus ST91KM, is bactericidal to Streptococcus agalactiae, Streptococcus dysgalactiae, Streptococcus uberis and Staphylococcus aureus associated with mastitis infections, including strains resistant to methicillin and oxacillin. Sensitive cells were deformed and secreted nucleotides, K+ and β-galactosidase when exposed to macedocin ST91KM. Adsorption of the peptide to target cells decreased in the presence of solvents, suggesting that receptors on the cell surfaces have lipid moieties. No adsorption was recorded in the presence of MgCl2, KI and Na2CO3, suggesting that ionic strength plays an important role. A teat seal preparation containing macedocin ST91KM effectively released the peptide and inhibited the growth of S. agalactiae. Macedocin ST91KM could form the basis for alternative dry cow therapy to prevent mastitis infections in dairy cows as it is effective against pathogens that display resistance to conventional antibiotic therapy.

  11. Controlling Listeria monocytogenes on Pork Meat with Combinations of Lyophilized Cell-adsorbed Bacteriocin of Lactobacillus curvatus CWBI-B28 and Organic Acids or Salts

    Directory of Open Access Journals (Sweden)

    Privat Kouakou

    2016-06-01

    Full Text Available The main aim of this study was to see if the antilisterial action of lyophilized cell-adsorbed bacteriocin from Lactobacillus curvatus CWBI-B28 might be reinforced by simultaneous treatment with an organic acid or salt. Slices of raw pork (lean bacon inoculated with Listeria monocytogenes (at 102 cfu/g meat were either vacuum packaged directly and stored at 4°C or treated prior to packaging with a solution containing either lyophilized cell-adsorbed bacteriocin from Lactobacillus curvatus CWBI-B28 (at 1 g/100 mL, an organic acid or salt, or both. The organic acids/salts used were acetic acid, lactic acid, sodium acetate, sodium diacetate, potassium sorbate, and potassium benzoate and the concentrations of the corresponding solutions were calculated so as to treat each slice with approximately 0.1, 0.3, or 0.5 mg acid/salt. Of the antimicrobials used alone, LCaB had the strongest inhibitory effect (a 1-Log reduction in the Listeria cfu count after two weeks, followed by an increase. In combination with LCaB, three antimicrobials had a much more drastic effect: acetic acid, sodium diacetate, and potassium benzoate. At the highest acid/salt concentration tested in such combinations, Listeria became undetectable after one or two weeks and remained so until the end of the 6-week experiment.

  12. Bacteriocin-producing strains of Lactobacillus plantarum inhibit adhesion of Staphylococcus aureus to extracellular matrix: quantitative insight and implications in antibacterial therapy.

    Science.gov (United States)

    Mukherjee, Sandipan; Ramesh, Aiyagari

    2015-12-01

    In the present study, the adhesion of bacteriocin-producing probiotic strains of Lactobacillus plantarum onto extracellular matrix (ECM) proteins such as collagen and mucin and their potential to prevent pathogen invasion onto the ECM was ascertained. Fluorescence-based in vitro assays indicated that L. plantarum strains CRA21, CRA38 and CRA52 displayed considerable adhesion to ECM molecules, which was comparable to the probiotic Lactobacillus rhamnosus GG. Flow cytometry-based quantitative assessment of the adhesion potential suggested that L. plantarum CRA21 exhibited superior adhesion onto the ECM as compared with other lactic acid bacteria strains. Furthermore, fluorescence-based assays suggested that the highest inhibition of Staphylococcus aureus adhesion onto collagen and mucin by bacteriocin-producing L. plantarum strains was observed in the exclusion mode as compared with the competition and displacement modes. This observation was supported by the higher binding affinity (k(d)) for the ECM exhibited by the L. plantarum strains as compared with S. aureus. Interestingly, a crude plantaricin A extract from food isolates of L. plantarum displayed potent antibacterial activity on ECM-adhered S. aureus cells. It is envisaged that the L. plantarum isolates displaying bacteriocinogenic and ECM-adhering traits can perhaps be explored to develop safe antibacterial therapeutic agents. PMID:26445850

  13. Molecular detection and sensitivity to antibiotics and bacteriocins of pathogens isolated from bovine mastitis in family dairy herds of central Mexico.

    Science.gov (United States)

    León-Galván, Ma Fabiola; Barboza-Corona, José E; Lechuga-Arana, A Arianna; Valencia-Posadas, Mauricio; Aguayo, Daniel D; Cedillo-Pelaez, Carlos; Martínez-Ortega, Erika A; Gutierrez-Chavez, Abner J

    2015-01-01

    Thirty-two farms (n = 535 cows) located in the state of Guanajuato, Mexico, were sampled. Pathogens from bovine subclinical mastitis (SCM) and clinical mastitis (CLM) were identified by 16S rDNA and the sensitivity to both antibiotics and bacteriocins of Bacillus thuringiensis was tested. Forty-six milk samples were selected for their positive California Mastitis Test (CMT) (≥3) and any abnormality in the udder or milk. The frequency of SCM and CLM was 39.1% and 9.3%, respectively. Averages for test day milk yield (MY), lactation number (LN), herd size (HS), and number of days in milk (DM) were 20.6 kg, 2.8 lactations, 16.7 animals, and 164.1 days, respectively. MY was dependent on dairy herd (DH), LN, HS, and DM (P Brevibacterium stationis, B. conglomeratum, and Staphylococcus agnetis. Bacterial isolates were resistant to penicillin, clindamycin, ampicillin, and cefotaxime. Bacteriocins synthesized by Bacillus thuringiensis inhibited the growth of multiantibiotic resistance bacteria such as S. agnetis, S. equorum, Streptococcus uberis, Brevibacterium stationis, and Brachybacterium conglomeratum, but they were not active against S. sciuri, a microorganism that showed an 84% resistance to antibiotics tested in this study. PMID:25815326

  14. The Stable Interaction Between Signal Peptidase LepB of Escherichia coli and Nuclease Bacteriocins Promotes Toxin Entry into the Cytoplasm.

    Science.gov (United States)

    Mora, Liliana; Moncoq, Karine; England, Patrick; Oberto, Jacques; de Zamaroczy, Miklos

    2015-12-25

    LepB is a key membrane component of the cellular secretion machinery, which releases secreted proteins into the periplasm by cleaving the inner membrane-bound leader. We showed that LepB is also an essential component of the machinery hijacked by the tRNase colicin D for its import. Here we demonstrate that this non-catalytic activity of LepB is to promote the association of the central domain of colicin D with the inner membrane before the FtsH-dependent proteolytic processing and translocation of the toxic tRNase domain into the cytoplasm. The novel structural role of LepB results in a stable interaction with colicin D, with a stoichiometry of 1:1 and a nanomolar Kd determined in vitro. LepB provides a chaperone-like function for the penetration of several nuclease-type bacteriocins into target cells. The colicin-LepB interaction is shown to require only a short peptide sequence within the central domain of these bacteriocins and to involve residues present in the short C-terminal Box E of LepB. Genomic screening identified the conserved LepB binding motif in colicin-like ORFs from 13 additional bacterial species. These findings establish a new paradigm for the functional adaptability of an essential inner-membrane enzyme. PMID:26499796

  15. Molecular Detection and Sensitivity to Antibiotics and Bacteriocins of Pathogens Isolated from Bovine Mastitis in Family Dairy Herds of Central Mexico

    Directory of Open Access Journals (Sweden)

    Ma. Fabiola León-Galván

    2015-01-01

    Full Text Available Thirty-two farms (n=535 cows located in the state of Guanajuato, Mexico, were sampled. Pathogens from bovine subclinical mastitis (SCM and clinical mastitis (CLM were identified by 16S rDNA and the sensitivity to both antibiotics and bacteriocins of Bacillus thuringiensis was tested. Forty-six milk samples were selected for their positive California Mastitis Test (CMT (≥3 and any abnormality in the udder or milk. The frequency of SCM and CLM was 39.1% and 9.3%, respectively. Averages for test day milk yield (MY, lactation number (LN, herd size (HS, and number of days in milk (DM were 20.6 kg, 2.8 lactations, 16.7 animals, and 164.1 days, respectively. MY was dependent on dairy herd (DH, LN, HS, and DM P<0.01, and correlations between udder quarters from the CMT were around 0.49 P<0.01. Coagulase-negative staphylococci were mainly identified, as well as Staphylococcus aureus, Streptococcus uberis, Brevibacterium stationis, B. conglomeratum, and Staphylococcus agnetis. Bacterial isolates were resistant to penicillin, clindamycin, ampicillin, and cefotaxime. Bacteriocins synthesized by Bacillus thuringiensis inhibited the growth of multiantibiotic resistance bacteria such as S. agnetis, S. equorum, Streptococcus uberis, Brevibacterium stationis, and Brachybacterium conglomeratum, but they were not active against S. sciuri, a microorganism that showed an 84% resistance to antibiotics tested in this study.

  16. Does Class Size Matter?

    Science.gov (United States)

    Ehrenberg, Ronald G.; Brewer, Dominic J.; Gamoran, Adam; Willms, J. Douglas

    2001-01-01

    Reports on the significance of class size to student learning. Includes an overview of class size in various countries, the importance of teacher adaptability, and the Asian paradox of large classes allied to high test scores. (MM)

  17. Secondary cluster ion distributions produced by MeV ion impacts on Group IIA oxides and nitrates

    Science.gov (United States)

    Ferrell, W. R.; von Heimburg, S. L.; van Stipdonk, M. J.; Schweikert, E. A.

    1996-10-01

    Cluster ion distributions from MeV atomic ion impacts (fission fragments from 252Cf on divalent Group IIA (GIIA) oxides and nitrates have been examined. The two predominant positive cluster species observed from both solids, (MO)nH+ and (MO)n M+ (M denotes metal atom) are evidence of a localized plasma state thought to be created by discrete MeV ion impacts. Cluster intensities and extent of clustering from nitrates were generally greater than those from oxides. The enhanced abundances at certain "magic numbers" of n observed in the mass spectra are believed to arise during the actual cluster production process. These periodic enhancements in cluster stabilities are attributed to the adoption by size-specific clusters of atomic arrangements analogous to segments of the rock salt lattice of the GIIA oxides. Cluster stabilities for the GIIA oxides and nitrates are influenced by the ionicity of M-O bonds, formal valence of metal and radius of cation.

  18. One-point functions of non-SUSY operators at arbitrary genus in a matrix model for type IIA superstrings

    CERN Document Server

    Kuroki, Tsunehide

    2016-01-01

    In the previous paper, the authors pointed out correspondence between a supersymmetric double-well matrix model and two-dimensional type IIA superstring theory on a Ramond-Ramond background from the viewpoint of symmetry and spectrum. This was confirmed by agreement between planar correlation functions in the matrix model and tree-level amplitudes in the superstring theory. In order to investigate the correspondence further, in this paper we compute correlation functions to all order of genus expansion in the double scaling limit of the matrix model. One-point functions of operators protected by supersymmetry terminate at some finite order, whereas those of unprotected operators yield non-Borel summable series. The behavior of the latter is characteristic in string perturbation series, providing further evidence that the matrix model describes a string theory. Moreover, instanton corrections to the planar one-point functions are also computed, and universal logarithmic scaling behavior is found for non-supers...

  19. N =3 solution in dyonic ISO(7) gauged maximal supergravity and its uplift to massive type IIA supergravity

    Science.gov (United States)

    Pang, Yi; Rong, Junchen

    2015-10-01

    We consider a certain N =1 supersymmetric, SO (3 )×SO (3 ) invariant, subsector of the dyonic ISO(7)-gauged maximal supergravity in four dimensions. The theory contains two scalar fields and two pseudoscalar fields. We look for stationary points of the scalar potential, especially the one preserving N =3 supersymmetry of the original ISO(7) gauged theory. The N =3 stationary point corresponding to the AdS vacuum in the D =4 theory is lifted to a warped AdS4×X6 type solution in massive type IIA supergravity. This D =10 background should be the dual of a certain N =3 Chern-Simons matter theory in three dimensions.

  20. High number of CD45RO+ tumor infiltrating lymphocytes is an independent prognostic factor in non-metastasized (stage I-IIA) esophageal adenocarcinoma

    International Nuclear Information System (INIS)

    The validation of novel prognostic indicators is of greatest interest for the management of esophageal adenocarcinoma (Barrett's cancer), particularly for non-metastasized (stage I-IIA) disease. The prognostic role of tumor infiltrating T-lymphocytes (TILs) in Barrett's cancer has not been reported so far. Here we evaluated the impact of TILs on survival, recurrence, and metastasis in Barrett's cancer, particularly in stage I-IIA patients. The levels of the adaptive immune markers CD3, CD8, and CD45RO were analyzed by immunohistochemistry and image analysis in tissue microarrays consisting of tumor tissues of 118 patients with primary resected Barrett's cancer. The findings were correlated with clinicopathological parameters including patient outcome. In multivariate analysis, a low density of intratumoral CD45RO+ immune cells was an independent unfavorable factor for disease-free survival in stages I-IIA patients (P = 0.004, RR = 4.7, 95% CI = 1.6-13.5) as well in the entire cohort (P = 0.048, RR = 2.0, 95% CI = 1.0-4.0). High CD3+ and CD45RO+ levels were associated with prolonged disease-free survival and overall survival as well with low recurrence rates of disease (P = 0.005 and P = 0.018, respectively). In addition, low CD3+ levels were correlated with a higher frequency of lymph node metastasis (P = 0.025). This study demonstrates that the density of CD45RO+ TILs is an independent prognostic factor in non-metastasized (stage I-IIA) Barrett's cancer patients and indicates an important role for the adaptive immunologic microenvironment. The inclusion of CD45RO+ density may help to improve the management of stage I-IIA Barrett's cancer

  1. Effects of tanshinone IIA on fibrosis in a rat model of cirrhosis through heme oxygenase-1, inflammation, oxidative stress and apoptosis.

    Science.gov (United States)

    Shu, Ming; Hu, Xiao-Rong; Hung, Zuo-An; Huang, Dam-Dan; Zhang, Shun

    2016-04-01

    Tanshinone IIA is extracted from the root of Salvia miltiorrhiza and used in traditional Chinese medicine for its anti-inflammatory activity and antioxidant effects. The aim of the present study was to investigate the potential protective effects of tanshinone IIA against fibrosis in a rat model of cirrhosis and to elucidate the underlying mechanisms. Male Sprague Dawley rats were used as the model of cirrhosis in the present study. In the cirrhotic rats, the extent of fibrosis, levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), heme oxygenase‑1 (HO‑1) protein expression, serum levels of nuclear factor (NF)‑κB, tumor necrosis factor‑α (TNF‑α), interleukin (IL)‑1β and IL‑6, superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH‑PX), and the protein expression levels of phosphorylated‑p38 mitogen‑activated protein kinase (MAPK) were all significantly increased. However, the serum malondialdehyde (MDA) activity and protein kinase B (Akt) protein expression were suppressed in cirrhotic rats compared with the sham (control) group. Compared with the cirrhotic group, administration of tanshinone IIA reduced the extent of fibrosis, levels of ALT and AST, HO‑1 protein expression, serum NF‑κB, TNF‑α, IL‑1β and IL‑6 levels, and the activity of SOD, CAT and GSH‑PX. Furthermore, administration of tanshinone IIA significantly increased the inhibition of the serum MDA activity and the Akt protein expression in cirrhotic rats compared with those in the cirrhotic group. The protective effect of tanshinone IIA suppresses fibrosis in a rat model of cirrhosis, and reduces inflammation and oxidative stress, via the HO‑1, Akt and p38 MAPK signaling pathway. PMID:26936326

  2. Nasal immunization with mannan-decorated mucoadhesive HPMCP microspheres containing ApxIIA toxin induces protective immunity against challenge infection with Actinobacillus pleuropneumoiae in mice.

    Science.gov (United States)

    Li, Hui-Shan; Shin, Min-Kyoung; Singh, Bijay; Maharjan, Sushila; Park, Tae-Eun; Kang, Sang-Kee; Yoo, Han-Sang; Hong, Zhong-Shan; Cho, Chong-Su; Choi, Yun-Jaie

    2016-07-10

    The development of subunit mucosal vaccines requires an appropriate delivery system or an immune modulator such as an adjuvant to improve antigen immunogenicity. The nasal route for vaccine delivery by microparticles has attracted considerable interest, although challenges such as the rapid mucociliary clearance in the respiratory mucosa and the low immunogenicity of subunit vaccine still remain. Here, we aimed to develop mannan-decorated mucoadhesive thiolated hydroxypropylmethyl cellulose phthalate (HPMCP) microspheres (Man-THM) that contain ApxIIA subunit vaccine - an exotoxin fragment as a candidate for a subunit nasal vaccine against Actinobacillus pleuropneumoniae. For adjuvant activity, mucoadhesive thiolated HPMCP microspheres decorated with mannan could be targeted to the PRRs (pathogen recognition receptors) and mannose receptors (MR) of antigen presenting cells (APCs) in the respiratory immune system. The potential adjuvant ability of Man-THM for intranasal immunization was confirmed by in vitro and in vivo experiments. In a mechanistic study using APCs in vitro, it was found that Man-THM enhanced receptor-mediated endocytosis by stimulating the MR of APCs. In vivo, the nasal vaccination of ApxIIA-loaded Man-THM in mice resulted in higher levels of mucosal sIgA and serum IgG than mice in the ApxIIA and ApxIIA-loaded THM groups due to the specific recognition of the mannan in the Man-THM by the MRs of the APCs. Moreover, ApxIIA-containing Man-THM protected immunized mice when challenged with strains of A. pleuropneumoniae serotype 5. These results suggest that mucoadhesive Man-THM may be a promising candidate for a nasal vaccine delivery system to elicit systemic and mucosal immunity that can protect from pathogenic bacteria infection. PMID:27189136

  3. Inhibition of Tanshinone IIA, Salvianolic Acid A and Salvianolic Acid B on Areca Nut Extract-Induced Oral Submucous Fibrosis in Vitro

    Directory of Open Access Journals (Sweden)

    Jian-Ping Dai

    2015-04-01

    Full Text Available Salvia miltiorrhiza Bunge has been reported to possess excellent antifibrotic activity. In this study, we have investigated the effect and mechanism of tanshinone IIA (Tan-IIA, salvianolic acid A (Sal-A and salvianolic acid B (Sal-B, the important active compounds of Salvia miltiorrhiza Bunge, on areca nut extract (ANE-induced oral submucous fibrosis (OSF in vitro. Through human procollagen gene promoter luciferase reporter plasmid assay, hydroxyproline assay, gelatin zymography assay, qRT-PCR, ELISA and Western blot assay, the influence of these three compounds on ANE-stimulated cell viability, collagen accumulation, procollagen gene transcription, MMP-2/-9 activity, MMP-1/-13 and TIMP-1/-2 expression, cytokine secretion and the activation of PI3K/AKT, ERK/JNK/p38 MAPK and TGF-β/Smads pathways were detected. The results showed that Tan-IIA, Sal-A and Sal-B could significantly inhibit the ANE-stimulated abnormal viability and collagen accumulation of mice oral mucosal fibroblasts (MOMFs, inhibit the transcription of procollagen gene COL1A1 and COL3A1, increase MMP-2/-9 activity, decrease TIMP-1/-2 expression and inhibit the transcription and release of CTGF, TGF-β1, IL-6 and TNF-α; Tan-IIA, Sal-A and Sal-B also inhibited the ANE-induced activation of AKT and ERK MAPK pathways in MOMFs and the activation of TGF-β/Smads pathway in HaCaT cells. In conclusion, Tan-IIA, Sal-A and Sal-B possess excellent antifibrotic activity in vitro and can possibly be used to promote the rehabilitation of OSF patients.

  4. Irradiation alone or in combination with surgery in stage IB and IIA carcinoma of the uterine cervix

    International Nuclear Information System (INIS)

    This is a report of a nonrandomized comparison of treatment results of 244 patients with stage IB carcinoma of the uterine cervix treated by radiation alone and 92 treated with preoperative radiation and surgery and 77 patients with stage IIA treated by radiation alone and 24 treated with a combination of radiation and surgery. The techniques or irradiation and types of operation are described in detail. The five-year tumor free actuarial survival for the patients with stage IB treated either with irradiation alone or combined with surgery was approximately 85% and the ten-year survival, 78%. Of the 24 patients treated with irradiation and surgery, there were two parametrial recurrences combined with distant metastasis (8.2%). There was no significant difference in the survival or recurrence rate of the patients treated with either method. In the group treated with combined therapy, patients with stage IB who showed evidence of microscopic residual tumor after irradiation had a failure rate of approximately 42% (8/18) in contrast to only 8.6% (6/70) in those with negative specimens. In stage IIA there were three failures in eight patients with residual tumor in the specimen in contrast to only two of 16 with negative specimens (12.5%). Major complications were comparable in both groups (radiation alone approximately 8.7% and irradiation combined with surgery approximately 14%); the difference is not statistically significant. The most frequent minor complication in patients treated with radiation alone was vaginal fibrosis (30 patients--9%) or vaginal vault necrosis

  5. Divercin V41 from gene characterization to food applications: 1998-2008, a decade of solved and unsolved questions.

    Science.gov (United States)

    Rihakova, J; Belguesmia, Y; Petit, V W; Pilet, M F; Prévost, H; Dousset, X; Drider, D

    2009-01-01

    The emergence of an increasing number of antibiotic resistant human clinical bacteria has been a great cause of concern for the last decades. As an example, Staphylococcus aureus isolates in the hospital environment are becoming more and more resistant to antibiotics including vancomycin which is considered as a last line of defence in treatment of Staphylococcus aureus-resistant methicillin. On the other hand, food safety is threatened by development of pathogenic bacteria including Listeria monocytogenes, Campylobacter jejuni, Salmonella enteritidis, Escherichia coli O157:H7 and Staphylococcus aureus. The use of antimicrobial peptides such as glycopeptides, semi-synthetic peptides, bacteriocins including lantibiotics offers a hope to face these clinical and food microbiology concerns. Clinical approval of new chemotherapeutic agents requires a long period of time. Research on bacteriocins has demonstrated potential use to fight against undesired foodborne pathogens but the use industrial use of bacteriocins is limited. To date only lantibiotic nisin and in class IIa bacteriocin Pediocin PA-1 are legally used as food preservative in many countries. The present minireview is focused on divercin V41 (DvnV41), a class IIa bacteriocin naturally produced by Carnobacterium divergens V41. The last decade has been the witness of intensive investigations carried out on this cationic peptide tempting to answer multiple questions covering basic and applied aspects. DvnV41 has shown a wide spectrum of activity either alone or in combination with nisin and/or polymixins (synergistic effect). This outcome indicates that Cb. divergens V41 could potentially be used for safe and efficient prevention of L. monocytogenes growth in cold smoked salmon. PMID:19018960

  6. Rho-kinase signaling controls nucleocytoplasmic shuttling of class IIa Histone Deacetylase (HDAC7) and transcriptional activation of orphan nuclear receptor NR4A1

    International Nuclear Information System (INIS)

    Rho-kinase (ROCK) has been well documented to play a key role in RhoA-induced actin remodeling. ROCK activation results in myosin light chain (MLC) phosphorylation either by direct action on MLC kinase (MLCK) or by inhibition of MLC phosphatase (MLCP), modulating actin–myosin contraction. We found that inhibition of the ROCK pathway in induced pluripotent stem cells, leads to nuclear export of HDAC7 and transcriptional activation of the orphan nuclear receptor NR4A1 while in cells with constitutive ROCK hyperactivity due to loss of function of the RhoGTPase activating protein Oligophrenin-1 (OPHN1), the orphan nuclear receptor NR4A1 is downregulated. Our study identify a new target of ROCK signaling via myosin phosphatase subunit (MYPT1) and Histone Deacetylase (HDAC7) at the nuclear level and provide new insights in the cellular functions of ROCK. - Highlights: • ROCK regulates nucleocytoplasmic shuttling of HDAC7 via phosphorylation of MYPT1. • Nuclear export of HDAC7 and upregulation of NR4A1 occurs with low ROCK activity. • High levels of ROCK activity due to OPHN1 loss of function downregulate NR4A1

  7. Rho-kinase signaling controls nucleocytoplasmic shuttling of class IIa Histone Deacetylase (HDAC7) and transcriptional activation of orphan nuclear receptor NR4A1

    Energy Technology Data Exchange (ETDEWEB)

    Compagnucci, Claudia; Barresi, Sabina [Unit of Molecular Medicine for Neuromuscular and Neurodegenerative Disorders, Department of Neurosciences, Bambino Gesù Children’s Hospital, IRCCS, Rome (Italy); Petrini, Stefania [Research Laboratories, Confocal Microscopy Core Facility, Bambino Gesù Children’s Hospital, IRCCS, Rome (Italy); Bertini, Enrico [Unit of Molecular Medicine for Neuromuscular and Neurodegenerative Disorders, Department of Neurosciences, Bambino Gesù Children’s Hospital, IRCCS, Rome (Italy); Zanni, Ginevra, E-mail: ginevra.zanni@opbg.net [Unit of Molecular Medicine for Neuromuscular and Neurodegenerative Disorders, Department of Neurosciences, Bambino Gesù Children’s Hospital, IRCCS, Rome (Italy)

    2015-04-03

    Rho-kinase (ROCK) has been well documented to play a key role in RhoA-induced actin remodeling. ROCK activation results in myosin light chain (MLC) phosphorylation either by direct action on MLC kinase (MLCK) or by inhibition of MLC phosphatase (MLCP), modulating actin–myosin contraction. We found that inhibition of the ROCK pathway in induced pluripotent stem cells, leads to nuclear export of HDAC7 and transcriptional activation of the orphan nuclear receptor NR4A1 while in cells with constitutive ROCK hyperactivity due to loss of function of the RhoGTPase activating protein Oligophrenin-1 (OPHN1), the orphan nuclear receptor NR4A1 is downregulated. Our study identify a new target of ROCK signaling via myosin phosphatase subunit (MYPT1) and Histone Deacetylase (HDAC7) at the nuclear level and provide new insights in the cellular functions of ROCK. - Highlights: • ROCK regulates nucleocytoplasmic shuttling of HDAC7 via phosphorylation of MYPT1. • Nuclear export of HDAC7 and upregulation of NR4A1 occurs with low ROCK activity. • High levels of ROCK activity due to OPHN1 loss of function downregulate NR4A1.

  8. Loosely coupled class families

    DEFF Research Database (Denmark)

    Ernst, Erik

    2001-01-01

    Families of mutually dependent classes that may be accessed polymor- phically provide an advanced tool for separation of concerns, in that it enables client code to use a group of instances of related classes safely without depending on the exact classes involved. However, class families which are...... expressed using virtual classes seem to be very tightly coupled internally. While clients have achieved the freedom to dynamically use one or the other family, it seems that any given family contains a xed set of classes and we will need to create an entire family of its own just in order to replace one of...... the members with another class. This paper shows how to express class families in such a manner that the classes in these families can be used in many dierent combinations, still enabling family polymorphism and ensuring type safety....

  9. Bacteriocins from Lactobacillus plantarum production, genetic organization and mode of action: produção, organização genética e modo de ação Bacteriocinas de Lactobacillus plantarum

    Directory of Open Access Journals (Sweden)

    Svetoslav D. Todorov

    2009-06-01

    Full Text Available Bacteriocins are biologically active proteins or protein complexes that display a bactericidal mode of action towards usually closely related species. Numerous strains of bacteriocin producing Lactobacillus plantarum have been isolated in the last two decades from different ecological niches including meat, fish, fruits, vegetables, and milk and cereal products. Several of these plantaricins have been characterized and the aminoacid sequence determined. Different aspects of the mode of action, fermentation optimization and genetic organization of the bacteriocin operon have been studied. However, numerous of bacteriocins produced by different Lactobacillus plantarum strains have not been fully characterized. In this article, a brief overview of the classification, genetics, characterization, including mode of action and production optimization for bacteriocins from Lactic Acid Bacteria in general, and where appropriate, with focus on bacteriocins produced by Lactobacillus plantarum, is presented.Bacteriocinas são proteínas ou complexos protéicos biologicamente ativos que apresentam atividade bactericida contra espécies relacionadas. Nas ultimas duas décadas, várias cepas de Lactobacillus plantarum produtoras de bacteriocinas foram isoladas de diferentes nichos ecológicos como carnes, peixes, frutas, vegetais e produtos lácteos e de cereais. Várias plantaricinas foram caracterizadas e suas seqüências de aminoácidos determinadas. Diferentes aspectos do modo de ação, otimização da fermentação e organização genética já foram estudados. Entretanto, muitas bacteriocinas produzidas por diferentes cepas de Lactobacillus plantarum ainda não foram completamente caracterizadas.Nesse artigo, apresenta-se uma breve revisão sobre a classificação, genética, caracterização, modo de ação, e otimização da produção de bacteriocinas de bactérias láticas em geral, e, quando apropriado, de bacteriocinas de Lactobacillus plantarum.

  10. Primary radiotherapy of stage IIA/B-IIIB cervical carcinoma. A comparison of continuous versus sequential regimens

    International Nuclear Information System (INIS)

    Background: comprehensive literature on cervical cancer demonstrates, even today, the need for optimization of the timing of external-beam radiotherapy (EBRT) and high-dose-rate brachytherapy (HDR-BT) in the treatment of stage IIA/B-IIIB cervical carcinoma. Patients and methods: 210 patients with carcinoma of the cervix were treated in the Municipal Center of Oncoradiology between January 1991 and December 1996 (FIGO IIA: n = 10, FIGO IIB: n = 113, and FIGO IIIB: n = 87). Two regimens were compared: sequential radiation therapy (SRT) with 4 x 8 Gy HDR-BT to point A followed by EBRT, and continuous radiation therapy (CRT) in which 5 x 6 Gy HDR-BT to point A, one session per week, was integrated into the EBRT. A total dose of 68-70 Gy to point A and 52-54 Gy to point B was given in EBRT with SRT, five fractions per week were applied. Four fractions per week were applied in CRT, i.e., no EBRT was performed on the day of HDR-BT. Total doses to points A and B were identical in both regimens. Overall treatment time (OTT) amounted to 56 days for SRT and 35 days for CRT. Median follow-up time was 3.4 (2.5-4.2) years. Results: progression-free 5-year-survival (PFS) was 71% in the CRT and 56% in the SRT group. Nevertheless, this difference was not statistically significant (p = 1.00), and the same was found in a subgroup analysis of the different tumor stages, showing, however, an unequivocal trend. Late bladder and rectal injuries occurred in 13% and 25%, respectively. Late rectal injuries were significantly more frequent with SRT than CRT (35 patients in the SRT and 18 patients in the CRT group; p = 0.037). This was due to the higher doses per fraction of HDR-BT in the SRT group. No difference was found regarding late bladder injuries (p = 0.837). Conclusion: for the patients included in this study, no advantage has been found so far in using CRT, i.e., shortening the OTT by weekly integration of HDR-BT into EBRT. Nevertheless, an obvious trend exists. The dose of 8 Gy per

  11. Preoperative radium therapy and radical hysterectomy in the treatment of cervical cancer stage IB, IIA, and initial IIB

    International Nuclear Information System (INIS)

    Patients with IB, IIa and in initial IIb cervical cancer were randomized for combined therapy, consisting of one or two radium insertion followed by Wertheim Meigs operation performed 40 days later. We look for the early and late complications of the treatment, residual cancer after radiotherapy and survival without recurrence. The project begin in 1965 and ended in 1986. All the operations were done by one of the investigators and 116 patients were analysed. The age ranged from 21 to 75 years with an average of 4.18 years. During the operations 31 (26.72%) patients needed 1.500 cc or greater amount of blood transfusion and we have 3 iliac veins lesions. Managing the ureters, we do our best to leave the posterior fascia as intact as possible. Post operative complications ranged from minor (fever, localised pelvic infections, temporary popliteal nerve paralysis) to evisceration (3 patients) deep venous thrombosis (3 patients) and two early urinary fistulas. Late complications were seen in patients submitted to sequential teletherapy irradiation. One uretrovaginal fistula occurred 10 month after treatment, another one, 7 years later and the third one 24 years later. One patient develop hydronefrosis and enterocolite after 7.000 rads of teletherapy and another one rectovaginal fistula 13 years after initial therapy. The shortening of the vagina making impossible the intercourse was seen in 7 patients. By the histological examination, the cervix was sterilized in 73.3 % of the patients. Residual cancer was found according the original size of the tumour and the stage of the disease. Studying different combinations between the existence of residual cervical cancer with positive or negative limphnodes and making a correlation with survival, we found the critical points is to have positive cervix and [positive lymphonodes. The five years survival (life table methodology) for stage 1 lesion was 96%; stage II, 67%. At ten years survival was slighted different. With positive

  12. Structure of the IIA domain of the glucose permease of Bacillus subtilis at 2.2-A resolution.

    Science.gov (United States)

    Liao, D I; Kapadia, G; Reddy, P; Saier, M H; Reizer, J; Herzberg, O

    1991-10-01

    The crystal structure of the IIA domain of the glucose permease of the phosphoenolpyruvate:sugar phosphotransferase system (PTS) from Bacillus subtilis has been determined at 2.2-A resolution. Refinement of the structure is in progress, and the current R-factor is 0.201 (R = sigma h parallel Fo magnitude of - Fc parallel/sigma h magnitude of Fo, where magnitude of Fo and magnitude of Fc are the observed and calculated structure factor amplitudes, respectively) for data between 6.0- and 2.2-A resolution for which F greater than or equal to 2 sigma (F). This is an antiparallel beta-barrel structure that incorporates "Greek key" and "jellyroll" topological motifs. A shallow depression is formed at the active site by part of the beta-sheet and an omega-loop flanking one side of the sheet. His83, the histidyl residue which is the phosphorylation target of HPr and which transfers the phosphoryl group to the IIB domain of the permease, is located at the C-terminus of a beta-strand. The N epsilon atom is partially solvated and also interacts with the N epsilon atom of a second histidyl residue, His68, located at the N-terminus of an adjacent beta-strand, suggesting they share a proton. The geometry of the hydrogen bond is imperfect, though. Electrostatic interactions with other polar groups and van der Waals contacts with the side chains of two flanking phenylalanine residues assure the precise orientation of the imidazole rings. The hydrophobic nature of the surface around the His83-His68 pair may be required for protein-protein recognition by HPr or/and by the IIB domain of the permease. The side chains of two aspartyl residues, Asp31 and Asp87, are oriented toward each other across a narrow groove, about 7 A from the active-site His83, suggesting they may play a role in protein-protein interaction. A model of the phosphorylated form of the molecule is proposed, in which oxygen atoms of the phosphoryl group interact with the side chain of His68 and with the main

  13. Persistence of the oral probiotic Streptococcus salivarius M18 is dose dependent and megaplasmid transfer can augment their bacteriocin production and adhesion characteristics.

    Science.gov (United States)

    Burton, Jeremy P; Wescombe, Philip A; Macklaim, Jean M; Chai, Melissa H C; Macdonald, Kyle; Hale, John D F; Tagg, John; Reid, Gregor; Gloor, Gregory B; Cadieux, Peter A

    2013-01-01

    Bacteriocin-producing probiotic Streptococcus salivarius M18 offers beneficial modulatory capabilities within the oral microbiome, apparently through potent inhibitory activity against potentially deleterious bacteria, such as Streptococcus pyogenes. The oral cavity persistence of S. salivarius M18 was investigated in 75 subjects receiving four different doses for 28 days. Sixty per cent of the subjects already had some inhibitor-producing S. salivarius in their saliva prior to probiotic intervention. Strain M18's persistence was dependent upon the dose, but not the period of administration. Culture analysis indicated that in some individuals the introduced strain had almost entirely replaced the indigenous S. salivarius, though the total numbers of the species did not increase. Selected subjects showing either high or low probiotic persistence had their salivary populations profiled using Illumina sequencing of the V6 region of the 16S rRNA gene. Analysis indicated that while certain bacterial phenotypes were markedly modulated, the overall composition of the oral microbiome was not modified by the probiotic treatment. Megaplasmids encoding bacteriocins and adhesion factors were transferred in vitro to generate a transconjugant S. salivarius exhibiting enhanced antimicrobial production and binding capabilities to HEp-2 cells. Since no widespread perturbation of the existing indigenous microbiota was associated with oral instillation and given its antimicrobial activity against potentially pathogenic streptococci, it appears that application of probiotic strain M18 offers potential low impact alternative to classical antibiotic prophylaxis. For candidate probiotic strains having relatively poor antimicrobial or adhesive properties, unique derivatives displaying improved probiotic performance may be engineered in vitro by megaplasmid transfer. PMID:23785463

  14. Persistence of the oral probiotic Streptococcus salivarius M18 is dose dependent and megaplasmid transfer can augment their bacteriocin production and adhesion characteristics.

    Directory of Open Access Journals (Sweden)

    Jeremy P Burton

    Full Text Available Bacteriocin-producing probiotic Streptococcus salivarius M18 offers beneficial modulatory capabilities within the oral microbiome, apparently through potent inhibitory activity against potentially deleterious bacteria, such as Streptococcus pyogenes. The oral cavity persistence of S. salivarius M18 was investigated in 75 subjects receiving four different doses for 28 days. Sixty per cent of the subjects already had some inhibitor-producing S. salivarius in their saliva prior to probiotic intervention. Strain M18's persistence was dependent upon the dose, but not the period of administration. Culture analysis indicated that in some individuals the introduced strain had almost entirely replaced the indigenous S. salivarius, though the total numbers of the species did not increase. Selected subjects showing either high or low probiotic persistence had their salivary populations profiled using Illumina sequencing of the V6 region of the 16S rRNA gene. Analysis indicated that while certain bacterial phenotypes were markedly modulated, the overall composition of the oral microbiome was not modified by the probiotic treatment. Megaplasmids encoding bacteriocins and adhesion factors were transferred in vitro to generate a transconjugant S. salivarius exhibiting enhanced antimicrobial production and binding capabilities to HEp-2 cells. Since no widespread perturbation of the existing indigenous microbiota was associated with oral instillation and given its antimicrobial activity against potentially pathogenic streptococci, it appears that application of probiotic strain M18 offers potential low impact alternative to classical antibiotic prophylaxis. For candidate probiotic strains having relatively poor antimicrobial or adhesive properties, unique derivatives displaying improved probiotic performance may be engineered in vitro by megaplasmid transfer.

  15. 30 CFR 57.22201 - Mechanical ventilation (I-A, I-B, I-C, II-A, II-B, III, IV, V-A, and V-B mines).

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Mechanical ventilation (I-A, I-B, I-C, II-A, II...-UNDERGROUND METAL AND NONMETAL MINES Safety Standards for Methane in Metal and Nonmetal Mines Ventilation § 57.22201 Mechanical ventilation (I-A, I-B, I-C, II-A, II-B, III, IV, V-A, and V-B mines). All mines...

  16. Bacteriocin production by Lactobacillus plantarum AMA-K isolated from Amasi, a Zimbabwean fermented milk product and study of the adsorption of bacteriocin AMA-K to Listeria sp. Otimização da produção de bacteriocina por Lactobacillus plantarum AMA-K isolado de Amasi, um produto lácteo fermentado de Zimbabwe, e estudo da adsorção da bacteriocina AMA-K à Listeria innocua, Listeria monocytogenes e Listeria ivanovii subsp. ivanovii

    Directory of Open Access Journals (Sweden)

    Svetoslav D. Todorov

    2008-03-01

    Full Text Available Bacteriocin AMA-K produced by Lactobacillus plantarum AMA-K inhibits the growth of Enterococcus spp., Escherichia coli, Klebsiella pneumoniae and Listeria spp. Growth of strain AMA-K in BHI, M17, soy milk and molasses was similar to growth in MRS. The effect of organic nitrogen sources, carbohydrates, glycerol, K2HPO4 and KH2PO4, MgSO4, MnSO4, tri-ammonium citrate, Tween 80, vitamins and initial pH on bacteriocin AMA-K was determined. The mode of action of bacteriocin AMA-K was studied. The effect of bacteriocin AMA-K to actively growing Listeria innocua LMG13568, L. ivanovii subsp. ivanovii ATCC19119 and L. monocytogenes ScottA was determined. Adsorption of bacteriocin AMA-K to target cells at different temperatures, pH and in presence of Tween 20, Tween 80, ascorbic acid, potassium sorbate, sodium nitrate and sodium chloride were studied. Bacteriocin AMA-K shares high homology to pediocin PA-1.A bacteriocina AMA-K produzida por Lactobacillus plantarum AMA-K inibe a multiplicação de Enterococcus spp, Escherichia coli, Klebsiella pneumoniae e Listeria spp. A multiplicação da cepa AMA-K em BHI, leite de soja e melaço foi semelhante à multiplicação em MRS. O efeito de fontes de nitrogênio orgânico, carboidratos, glicerol, K2HPO4 e KH2PO4, MgSO4, MnSO4, citrato de triamônio, Tween 80, vitaminas e pH inicial sobre a bacteriocina AMA-K foi determinada. O modo de ação da bacteriocina AMA-K foi estudado. O efeito da bacteriocina AMA-K sobre Listeria innocua LMG13568, Listeria ivanovii subsp.ivanovii ATCC19119 e Listeria monocytogenes Scott A foi determinado. A adsorção da bacteriocina AMA-K às células-alvo em diferentes temperaturas, pH e na presença de Tween 20, Tween 80, ácido ascórbico, sorbato de potássio, nitrato de sódio a cloreto de sódio foi avaliada. A bacteriocina AMA-K apresenta grande homologia a pediocina PA-1.

  17. The field and Killing spinor equations of M-theory and type IIA/IIB supergravity in coordinate-free notation

    CERN Document Server

    Hamilton, M J D

    2016-01-01

    We review the actions of the supergravity theory in eleven dimensions as well as the type IIA and IIB supergravities in ten dimensions and derive the bosonic equations of motion in a coordinate-free notation. We also consider the existence of supersymmetries and the associated generalized Killing spinor equations. The aim of this note is to serve as a formulary and make the equations of supergravity more easily accessible to mathematicians.

  18. Twenty-year results of treatment of patients with stage i-IIA Hodgkin's lymphoma using radiation therapy with accelerated dose fractionation

    International Nuclear Information System (INIS)

    The findings of investigation of 20-year survival of 234 patients with stage IA-IIA Hodgkin's lymphoma (HL) are analyzed. In case of a favorable prognosis according to EORTC criteria total relapse-free survival was 90 and 76% respectively at 10-year and 79 and 73% at 20 year terms of observation. The use of chemoradiation therapy at unfavorable prognosis eliminated the difference in the survival of the patients from different prognostic groups.

  19. Inhibition of Group IIA Secretory Phospholipase A2 and its Inflammatory Reactions in Mice by Ethanolic Extract of Andrographis paniculata, a Well-known Medicinal Food

    OpenAIRE

    V Kishore; N S Yarla; Zameer, F.; Nagendra Prasad, M. N.; Santosh, M. S.; S S More; Rao, D.G.; Bhadrapura Lakkappa Dhananjaya

    2016-01-01

    Andrographis paniculata Nees is an important medicinal plant found in the tropical regions of the world, which has been traditionally used in Indian and Chinese medicinal systems. It is also used as medicinal food. A. paniculata is found to exhibit anti-inflammatory activities; however, its inhibitory potential on inflammatory Group IIA phospholipases A2 (PLA2) and its associated inflammatory reactions are not clearly understood. The aim of the present study is to evaluate the inhibitory/neut...

  20. Nonmuscle Myosin Heavy Chain IIA Mutations Define a Spectrum of Autosomal Dominant Macrothrombocytopenias: May-Hegglin Anomaly and Fechtner, Sebastian, Epstein, and Alport-Like Syndromes

    OpenAIRE

    Heath, Karen E.; Campos-Barros, Angel; Toren, Amos; Rozenfeld-Granot, Galit; Carlsson, Lena E.; Savige, Judy; Denison, Joyce C.; Gregory, Martin C.; White, James G.; Barker, David F.; Greinacher, Andreas; Epstein, Charles J.; Glucksman, Marc J.; Martignetti, John A.

    2001-01-01

    May-Hegglin anomaly (MHA) and Fechtner (FTNS) and Sebastian (SBS) syndromes are autosomal dominant platelet disorders that share macrothrombocytopenia and characteristic leukocyte inclusions. FTNS has the additional clinical features of nephritis, deafness, and cataracts. Previously, mutations in the nonmuscle myosin heavy chain 9 gene (MYH9), which encodes nonmuscle myosin heavy chain IIA (MYHIIA), were identified in all three disorders. The spectrum of mutations and the genotype-phenotype a...

  1. The Activity of the Lactose Transporter from Streptococcus thermophilus Is Increased by Phosphorylated IIA and the Action of β-Galactosidase

    OpenAIRE

    Geertsma, Eric R.; Duurkens, Ria H.; Poolman, Bert

    2005-01-01

    The metabolism of lactose by Streptococcus thermophilus is highly regulated, allowing the bacterium to prefer lactose over glucose as main source of carbon and energy. In vitro analysis of the enzymes involved in transport and hydrolysis of lactose showed that the transport reaction benefits from the hydrolysis of lactose at the trans side of the membrane. Furthermore, the activity of LacS is modulated by PEP-dependent phosphorylation of the IIA domain via the general energy coupling proteins...

  2. programs on paper: an examination of virginia's service delivery area jobh training partnership act title II-A job training plans

    OpenAIRE

    Evans, Gwynnen Stokes

    1997-01-01

    A key purpose of federal job training policy is to ensure that the workforce has the skills necessary to obtain and retain gainful employment. The purpose of this study was to describe and compare key elements of Virginia's fourteen service delivery area (SDA) plans in order to determine how they would deliver programs to achieve the stated purpose of JTPA Title II-A, which targets disadvantaged adults. In addition, the plans were evaluated as to their potentia...

  3. Collagen remodeling by phagocytosis is determined by collagen substrate topology and calcium-dependent interactions of gelsolin with nonmuscle myosin IIA in cell adhesions

    OpenAIRE

    Arora, P. D.; Wang, Y.; Bresnick, A.; Dawson, J.; Janmey, P. A.; McCulloch, C. A.

    2013-01-01

    We examine how collagen substrate topography, free intracellular calcium ion concentration ([Ca2+]i, and the association of gelsolin with nonmuscle myosin IIA (NMMIIA) at collagen adhesions are regulated to enable collagen phagocytosis. Fibroblasts plated on planar, collagen-coated substrates show minimal increase of [Ca2+]i, minimal colocalization of gelsolin and NMMIIA in focal adhesions, and minimal intracellular collagen degradation. In fibroblasts plated on collagen-coated latex beads th...

  4. Inhibition of group IIA secretory phospholipase A2and its inflammatory reactions in mice by ethanolic extract of Andrographis paniculata, a well-known medicinal food

    Directory of Open Access Journals (Sweden)

    V Kishore

    2016-01-01

    This study emphasis the anti-inflammatory effect of A. paniculata by inhibiting the inflammatory Group IIA sPLA2 and its associated inflammatory activities such as edema. It was found that there is a strong correlation between lipolytic activity and pro-inflammatory activity inhibition. Therefore, the study suggests that the extract processes potent anti-inflammatory agents, which could be developed as a potential therapeutic agent against inflammatory and related diseases.

  5. A Virtual Class Calculus

    DEFF Research Database (Denmark)

    Ernst, Erik; Ostermann, Klaus; Cook, William Randall

    2006-01-01

    , statically typed model for virtual classes has been a long-standing open question. This paper presents a virtual class calculus, vc, that captures the essence of virtual classes in these full-fledged programming languages. The key contributions of the paper are a formalization of the dynamic and static...

  6. Classification of criticality calculations with correlation coefficient method and its application to OECD/NEA burnup credit benchmarks phase III-A and II-A

    International Nuclear Information System (INIS)

    A method for classifying benchmark results of criticality calculations according to similarity was proposed in this paper. After formulation of the method utilizing correlation coefficients, it was applied to burnup credit criticality benchmarks Phase III-A and II-A, which were conducted by the Expert Group on Burnup Credit Criticality Safety under auspices of the Nuclear Energy Agency of the Organisation for Economic Cooperation and Development (OECD/NEA). Phase III-A benchmark was a series of criticality calculations for irradiated Boiling Water Reactor (BWR) fuel assemblies, whereas Phase II-A benchmark was a suite of criticality calculations for irradiated Pressurized Water Reactor (PWR) fuel pins. These benchmark problems and their results were summarized. The correlation coefficients were calculated and sets of benchmark calculation results were classified according to the criterion that the values of the correlation coefficients were no less than 0.15 for Phase III-A and 0.10 for Phase II-A benchmarks. When a couple of benchmark calculation results belonged to the same group, one calculation result was found predictable from the other. An example was shown for each of the Benchmarks. While the evaluated nuclear data seemed the main factor for the classification, further investigations were required for finding other factors. (author)

  7. Platelet half-life in patients with primary hyperlipoproteinemia type IIa, IIb, and IV according to Fredrickson with and without clinical signs of atherosclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Jaeger, E.; Sinzinger, H.; Widhalm, K.; Kaliman, J.; Hoefer, R. (Vienna Univ. (Austria). 2. Medizinische Klinik; Ludwig Boltzmann-Institut fuer Nuklearmedizin, Vienna (Austria); Vienna Univ. (Austria). Kinderklinik; Vienna Univ. (Austria). Kardiologische Klinik)

    1982-09-01

    It is generally accepted that platelet half-life is shortened in atherosclerotic vascular diseases. Concerning changes due to hyperlipoproteinemia (HLP), however, there exist only few data. Therefore, we examined the platelet-half life in 60 patients with recently discovered HLP type IIa, IIb and IV according to Fredrickson before treatment in comparison to 60 controls. 33 of the HLP-patients had no clinical symptoms of angiopathy. 27 patients suffered from peripheral vascular disease or from coronary heart disease as verified by angiography. The labelling of autologous platelets was performed with 100..mu..Ci of /sup 111/Indium-oxine-sulfate at 37/sup 0/C for 5 minutes. The mean labelling efficiency was 90%, the recovery after 2 hours about 70%. Serum lipoproteins were estimated by means of ultracentrifugation and polyanionprecipitation according to Lipid Research Clinic Methods. In the patients with HLP platelet half-life was significantly shortened in comparison to the control group (p < 0.01). These changes were most pronounced in patients with HLP-type IIa and with atherosclerotic lesions, respectively. In patients with HLP-type IIa a very close correlation could be demonstrated between platelet half-life and LDL-cholesterol (r = -0.72; p < 0.001) as well as total cholesterol (r = -0.73; p < 0.001). These data prove that in HLP in-vivo platelet function as measured by platelet survival is significantly influenced even before the occurrence of clinically relevant symptoms of atherosclerosis.

  8. Developing an Anticancer Copper(II) Pro-Drug Based on the His242 Residue of the Human Serum Albumin Carrier IIA Subdomain.

    Science.gov (United States)

    Qi, Jinxu; Zhang, Yao; Gou, Yi; Zhang, Zhenlei; Zhou, Zuping; Wu, Xiaoyang; Yang, Feng; Liang, Hong

    2016-05-01

    To increase delivery efficiency, anticancer activity, and selectivity of anticancer metal agents in vivo, we proposed to develop the anticancer metal pro-drug based on His242 residue of the human serum albumin (HSA) carrier IIA subdomain. To confirm our hypothesis, we prepared two Cu(II) compounds [Cu(P4 mT)Cl and Cu(Bp44 mT)Cl] by modifying Cu(II) compound ligand structure. Studies with two HSA complex structures revealed that Cu(P4 mT)Cl bound to the HSA subdomain IIA via hydrophobic interactions, but Cu(Bp44 mT)Cl bound to the HSA subdomain IIA via His242 replacement of a Cl atom of Cu(Bp44 mT)Cl, and a coordination to Cu(2+). Furthermore, Cu(II) compounds released from HSA could be regulated at different pHs. In vivo data revealed that the HSA-Cu(Bp44 mT) complex increased copper's selectivity and capacity of inhibiting tumor growth compared to Cu(Bp44 mT)Cl alone. PMID:27017838

  9. Platelet half-life in patients with primary hyperlipoproteinemia type IIa, IIb, and IV according to Fredrickson with and without clinical signs of atherosclerosis

    International Nuclear Information System (INIS)

    It is generally accepted that platelet half-life is shortened in atherosclerotic vascular diseases. Concerning changes due to hyperlipoproteinemia (HLP), however, there exist only few data. Therefore, we examined the platelet-half life in 60 patients with recently discovered HLP type IIa, IIb and IV according to Fredrickson before treatment in comparison to 60 controls. 33 of the HLP-patients had no clinical symptoms of angiopathy. 27 patients suffered from peripheral vascular disease or from coronary heart disease as verified by angiography. The labelling of autologous platelets was performed with 100μCi of 111Indium-oxine-sulfate at 370C for 5 minutes. The mean labelling efficiency was 90%, the recovery after 2 hours about 70%. Serum lipoproteins were estimated by means of ultracentrifugation and polyanionprecipitation according to Lipid Research Clinic Methods. In the patients with HLP platelet half-life was significantly shortened in comparison to the control group (p < 0.01). These changes were most pronounced in patients with HLP-type IIa and with atherosclerotic lesions, respectively. In patients with HLP-type IIa a very close correlation could be demonstrated between platelet half-life and LDL-cholesterol (r = -0.72; p < 0.001) as well as total cholesterol (r = -0.73; p < 0.001). These data prove that in HLP in-vivo platelet function as measured by platelet survival is significantly influenced even before the occurrence of clinically relevant symptoms of atherosclerosis. (Author)

  10. Identification of pyrazosulfuron-ethyl binding affinity and binding site subdomain IIA in human serum albumin by spectroscopic methods

    Science.gov (United States)

    Ding, Fei; Liu, Wei; Zhang, Xi; Wu, Li-Jun; Zhang, Li; Sun, Ying

    2010-03-01

    Pyrazosulfuron-ethyl (PY) is a sulfonylurea herbicide developed by DuPont which has been widely used for weed control in cereals. The determination of PY binding affinity and binding site in human serum albumin (HSA) by spectroscopic methods is the subject of this work. From the fluorescence emission, circular dichroism and three-dimensional fluorescence results, the interaction of PY with HSA caused secondary structure changes in the protein. Fluorescence data demonstrated that the quenching of HSA fluorescence by PY was the result of the formation of HSA-PY complex at 1:1 molar ratio, a static mechanism was confirmed to lead to the fluorescence quenching. Hydrophobic probe 8-anilino-1-naphthalenesulfonic acid (ANS) displacement results show that hydrophobic patches are the major sites for PY binding on HSA. The thermodynamic parameters Δ H° and Δ S° were calculated to be -36.32 kJ mol -1 and -35.91 J mol -1 K -1, which illustrated van der Waals forces and hydrogen bonds interactions were the dominant intermolecular force in stabilizing the complex. Also, site marker competitive experiments showed that the binding of PY to HSA took place primarily in subdomain IIA (Sudlow's site I). What presented in this paper binding research enriches our knowledge of the interaction between sulfonylurea herbicides and the physiologically important protein HSA.

  11. Quinoline-2-carboxaldehyde thiosemicarbazones and their Cu(II) and Ni(II) complexes as topoisomerase IIa inhibitors.

    Science.gov (United States)

    Bisceglie, Franco; Musiari, Anastasia; Pinelli, Silvana; Alinovi, Rossella; Menozzi, Ilaria; Polverini, Eugenia; Tarasconi, Pieralberto; Tavone, Matteo; Pelosi, Giorgio

    2015-11-01

    A series of quinoline-2-carboxaldehyde thiosemicarbazones and their copper(II) and nickel(II) complexes were synthesized and characterized. In all complexes the ligands are in the E configuration with respect to the imino bond and behave as terdentate. The copper(II) complexes form square planar derivatives with one molecule of terdentate ligand and chloride ion. A further non-coordinated chloride ion compensates the overall charge. Nickel(II) ions form instead octahedral complexes with two ligands for each metal ion, independently from the stoichiometric metal:ligand ratio used in the synthesis. Ligands and complexes were tested for their antiproliferative properties on histiocytic lymphoma cell line U937. Copper(II) derivatives are systematically more active than the ligands and the nickel complexes. All copper derivatives result in inhibiting topoisomerase IIa in vitro. Computational methods were used to propose a model to explain the different extent of inhibition presented by these compounds. The positive charge of the dissociated form of the copper complexes may play a key role in their action. PMID:26335598

  12. Characterization of the charge-carrier transport properties of IIa-Tech SC diamond for radiation detection applications

    International Nuclear Information System (INIS)

    Single crystal (SC) diamond has since years demonstrated its interest for the fabrication of radiation detectors, especially where the material properties are providing superior interests with respect to the detection application. Among the industrial suppliers able to provide on a commercial basis high-grade single crystal diamond, IIa-Tech has recently appeared in the market as a new player. The aim of this paper is to assess the quality of one SC sample when characterized under α-particles for the measurement of its carrier transport properties. We observed that full charge collection could be observed at biases as low as 0.11 V/μm with no space charge build-up (conventionally typical bias values used are closer to 1 V/μm). Velocity reached values of 38 μm/ns and 53 μm/ns for electrons and holes, respectively (values probed at 0.33 V/μm). Similarly, the α detection spectrum displays a sharp line demonstrating the good uniformity of the material over its surface. By combining the measurements with more conventional optical observations such as birefringence and cathodoluminescence spectroscopy, it comes that the material demonstrates its ability to be used as a detector, with properties that can compare with the highest grade materials today available on the market. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  13. Dlc1 interaction with non-muscle myosin heavy chain II-A (Myh9) and Rac1 activation.

    Science.gov (United States)

    Sabbir, Mohammad G; Dillon, Rachelle; Mowat, Michael R A

    2016-01-01

    The Deleted in liver cancer 1 (Dlc1) gene codes for a Rho GTPase-activating protein that also acts as a tumour suppressor gene. Several studies have consistently found that overexpression leads to excessive cell elongation, cytoskeleton changes and subsequent cell death. However, none of these studies have been able to satisfactorily explain the Dlc1-induced cell morphological phenotypes and the function of the different Dlc1 isoforms. Therefore, we have studied the interacting proteins associated with the three major Dlc1 transcriptional isoforms using a mass spectrometric approach in Dlc1 overexpressing cells. We have found and validated novel interacting partners in constitutive Dlc1-expressing cells. Our study has shown that Dlc1 interacts with non-muscle myosin heavy chain II-A (Myh9), plectin and spectrin proteins in different multiprotein complexes. Overexpression of Dlc1 led to increased phosphorylation of Myh9 protein and activation of Rac1 GTPase. These data support a role for Dlc1 in induced cell elongation morphology and provide some molecular targets for further analysis of this phenotype. PMID:26977077

  14. Dlc1 interaction with non-muscle myosin heavy chain II-A (Myh9 and Rac1 activation

    Directory of Open Access Journals (Sweden)

    Mohammad G. Sabbir

    2016-04-01

    Full Text Available The Deleted in liver cancer 1 (Dlc1 gene codes for a Rho GTPase-activating protein that also acts as a tumour suppressor gene. Several studies have consistently found that overexpression leads to excessive cell elongation, cytoskeleton changes and subsequent cell death. However, none of these studies have been able to satisfactorily explain the Dlc1-induced cell morphological phenotypes and the function of the different Dlc1 isoforms. Therefore, we have studied the interacting proteins associated with the three major Dlc1 transcriptional isoforms using a mass spectrometric approach in Dlc1 overexpressing cells. We have found and validated novel interacting partners in constitutive Dlc1-expressing cells. Our study has shown that Dlc1 interacts with non-muscle myosin heavy chain II-A (Myh9, plectin and spectrin proteins in different multiprotein complexes. Overexpression of Dlc1 led to increased phosphorylation of Myh9 protein and activation of Rac1 GTPase. These data support a role for Dlc1 in induced cell elongation morphology and provide some molecular targets for further analysis of this phenotype.

  15. Correlation of dysfunction of nonmuscle myosin IIA with increased induction of Cyp1a1 in Hepa-1 cells.

    Science.gov (United States)

    Ebina, Masayuki; Shibazaki, Masahiko; Kudo, Kyoko; Kasai, Shuya; Kikuchi, Hideaki

    2011-03-01

    The aryl hydrocarbon receptor (AhR) is one of the best known ligand-activated transcription factors and it induces Cyp1a1 transcription by binding with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Recent focus has been on the relationship of AhR with signaling pathways that modulate cell shape and migration. In nonmuscle cells, nonmuscle myosin II is one of the key determinants of cell morphology, but it has not been investigated whether its function is related to Cyp1a1 induction. In this study, we observed that (-)-blebbistatin, which is a specific inhibitor of nonmuscle myosin II, increased the level of CYP1A1-mRNA in Hepa-1 cells. Comparison of (-)-blebbistatin with (+)-blebbistatin, which is an inactive enantiomer, indicated that the increase of CYP1A1-mRNA was due to nonmuscle myosin II inhibition. Subsequent knockdown experiments observed that reduction of nonmuscle myosin IIA, which is only an isoform of nonmuscle myosin II expressed in Hepa-1 cells, was related to the enhancement of TCDD-dependent Cyp1a1 induction. Moreover, chromatin immunoprecipitation assay indicated that the increase of Cyp1a1 induction was the result of transcriptional activation due to increased binding of AhR and RNA polymerase II to the enhancer and proximal promoter regions of Cyp1a1, respectively. These findings provide a new insight into the correlation between the function of nonmuscle myosin II and gene induction. PMID:21216307

  16. Design of group IIA secreted/synovial phospholipase A(2 inhibitors: an oxadiazolone derivative suppresses chondrocyte prostaglandin E(2 secretion.

    Directory of Open Access Journals (Sweden)

    Jean-Edouard Ombetta

    Full Text Available Group IIA secreted/synovial phospholipase A(2 (GIIAPLA(2 is an enzyme involved in the synthesis of eicosanoids such as prostaglandin E(2 (PGE(2, the main eicosanoid contributing to pain and inflammation in rheumatic diseases. We designed, by molecular modeling, 7 novel analogs of 3-{4-[5(indol-1-ylpentoxy]benzyl}-4H-1,2,4-oxadiazol-5-one, denoted C1, an inhibitor of the GIIAPLA(2 enzyme. We report the results of molecular dynamics studies of the complexes between these derivatives and GIIAPLA(2, along with their chemical synthesis and results from PLA(2 inhibition tests. Modeling predicted some derivatives to display greater GIIAPLA(2 affinities than did C1, and such predictions were confirmed by in vitro PLA(2 enzymatic tests. Compound C8, endowed with the most favorable energy balance, was shown experimentally to be the strongest GIIAPLA(2 inhibitor. Moreover, it displayed an anti-inflammatory activity on rabbit articular chondrocytes, as shown by its capacity to inhibit IL-1beta-stimulated PGE(2 secretion in these cells. Interestingly, it did not modify the COX-1 to COX-2 ratio. C8 is therefore a potential candidate for anti-inflammatory therapy in joints.

  17. In situ production of pediocin PA-1 like bacteriocin by different genera of lactic acid bacteria in soymilk fermentation and evaluation of sensory properties of the fermented soy curd.

    Science.gov (United States)

    Devi, Sundru Manjulata; Ramaswamy, Asha Mysore; Halami, Prakash M

    2014-11-01

    The lactic acid bacteria (LAB) are found to produce bacteriocins with enhanced nutritive properties in the fermented foods. In the present study, the ability of LAB cultures (Pediococcus acidilactici NCIM 5424, Enterococcus faecium NCIM 5423 and Lactobacillus plantarum Acr2) to produce pediocin PA-1 like bacteriocin was evaluated during soymilk fermentation. The isolates E. faecium NCIM 5423 and Lb. plantarum Acr2 were able to produce bacteriocin as well as ferment soymilk within 6 h of incubation. Upon plating the cultures E. faecium NCIM 5423 and Lb. plantarum Acr2 in soymilk were found to be viable even after 15 days of storage at 4 °C. No significant variation was observed in the viable counts of E. faecium NCIM 5423 and Lb. plantarum Acr2 (P>0.05). The effect of crude bacteriocin on Listeria cells was evidenced through scanning electron microscope (SEM) photographs wherein cell membrane damage was observed. On co-cultivation of E. faecium NCIM 5423 and Lb. plantarum Acr2 individually with Listeria monocytogenes ScottA a decrease in the Listeria count was observed within 24 h of incubation. However, during co-cultivation of ScottA with P. acidilactici NCIM 5424, no significant difference was observed in the viable counts (P>0.05). The pH, titratable acidity, pediocin activity, anti-oxidant property and sensory attributes for E. faecium NCIM 5423 were studied. It was observed that E. faecium NCIM 5423 fermented soymilk had an acceptable sensory score during storage period. Hence, such culture can be an ideal starter for development of functional foods with longer shelf life. PMID:26396327

  18. Co-Circulation of Canine Coronavirus I and IIa/b with High Prevalence and Genetic Diversity in Heilongjiang Province, Northeast China.

    Directory of Open Access Journals (Sweden)

    Xinyu Wang

    Full Text Available To trace the evolution of canine coronavirus (CCoV, 201 stool samples from diarrheic dogs in northeast China were subjected to reverse transcription-polymerase chain reactions (RT-PCRs targeting the partial M and S genes of CCoV, followed by an epidemiological analysis. M gene RT-PCRs showed that 28.36% (57/201 of the samples were positive for CCoV; of the 57 positive samples, CCoV-I and CCoV-II accounted for 15.79% (9/57 and 84.21% (48/57, respectively. A sequence comparison of the partial M gene revealed nucleotide homologies of 88.4%-100% among the 57 CCoV strains, and 88.7%-96.2% identity between the 57 CCoV strains and the Chinese reference strain HF3. The CCoV-I and CCoV-II strains exhibited genetic diversity when compared with reference strains from China and other countries. The 57 CCoV strains exhibited high co-infection rates with canine kobuvirus (CaKV (33.33% and canine parvovirus-2 (CPV-2 (31.58%. The CCoV prevalence in diarrheic dogs differed significantly with immunization status, regions, seasons, and ages. Moreover, 28 S genes were amplified from the 57 CCoV-positive samples, including 26 CCoV-IIa strains, one CCoV-IIb strain, and one CCoV-I strain. A sequence comparison of the partial S gene revealed 86.3%-100% nucleotide identity among the 26 CCoV-IIa strains, and 89.6%-92.2% identity between the 26 CCoV-IIa strains and the Chinese reference strain V1. The 26 CCoV-IIa strains showed genetic diversity when compared with reference strains from China and other countries. Our data provide evidence that CCoV-I, CCoV-IIa, and CCoV-IIb strains co-circulate in the diarrhoetic dogs in northeast China, high co-infection rates with CaKV and CPV-2 were observed, and the CCoV-II strains exhibited high prevalence and genetic diversity.

  19. Co-Circulation of Canine Coronavirus I and IIa/b with High Prevalence and Genetic Diversity in Heilongjiang Province, Northeast China

    Science.gov (United States)

    Wang, Xinyu; Li, Chunqiu; Guo, Donghua; Wang, Xinyu; Wei, Shan; Geng, Yufei; Wang, Enyu; Wang, Zhihui; Zhao, Xiwen; Su, Mingjun; Liu, Qiujin; Zhang, Siyao; Feng, Li; Sun, Dongbo

    2016-01-01

    To trace the evolution of canine coronavirus (CCoV), 201 stool samples from diarrheic dogs in northeast China were subjected to reverse transcription-polymerase chain reactions (RT-PCRs) targeting the partial M and S genes of CCoV, followed by an epidemiological analysis. M gene RT-PCRs showed that 28.36% (57/201) of the samples were positive for CCoV; of the 57 positive samples, CCoV-I and CCoV-II accounted for 15.79% (9/57) and 84.21% (48/57), respectively. A sequence comparison of the partial M gene revealed nucleotide homologies of 88.4%–100% among the 57 CCoV strains, and 88.7%–96.2% identity between the 57 CCoV strains and the Chinese reference strain HF3. The CCoV-I and CCoV-II strains exhibited genetic diversity when compared with reference strains from China and other countries. The 57 CCoV strains exhibited high co-infection rates with canine kobuvirus (CaKV) (33.33%) and canine parvovirus-2 (CPV-2) (31.58%). The CCoV prevalence in diarrheic dogs differed significantly with immunization status, regions, seasons, and ages. Moreover, 28 S genes were amplified from the 57 CCoV-positive samples, including 26 CCoV-IIa strains, one CCoV-IIb strain, and one CCoV-I strain. A sequence comparison of the partial S gene revealed 86.3%–100% nucleotide identity among the 26 CCoV-IIa strains, and 89.6%–92.2% identity between the 26 CCoV-IIa strains and the Chinese reference strain V1. The 26 CCoV-IIa strains showed genetic diversity when compared with reference strains from China and other countries. Our data provide evidence that CCoV-I, CCoV-IIa, and CCoV-IIb strains co-circulate in the diarrhoetic dogs in northeast China, high co-infection rates with CaKV and CPV-2 were observed, and the CCoV-II strains exhibited high prevalence and genetic diversity. PMID:26771312

  20. Co-Circulation of Canine Coronavirus I and IIa/b with High Prevalence and Genetic Diversity in Heilongjiang Province, Northeast China.

    Science.gov (United States)

    Wang, Xinyu; Li, Chunqiu; Guo, Donghua; Wang, Xinyu; Wei, Shan; Geng, Yufei; Wang, Enyu; Wang, Zhihui; Zhao, Xiwen; Su, Mingjun; Liu, Qiujin; Zhang, Siyao; Feng, Li; Sun, Dongbo

    2016-01-01

    To trace the evolution of canine coronavirus (CCoV), 201 stool samples from diarrheic dogs in northeast China were subjected to reverse transcription-polymerase chain reactions (RT-PCRs) targeting the partial M and S genes of CCoV, followed by an epidemiological analysis. M gene RT-PCRs showed that 28.36% (57/201) of the samples were positive for CCoV; of the 57 positive samples, CCoV-I and CCoV-II accounted for 15.79% (9/57) and 84.21% (48/57), respectively. A sequence comparison of the partial M gene revealed nucleotide homologies of 88.4%-100% among the 57 CCoV strains, and 88.7%-96.2% identity between the 57 CCoV strains and the Chinese reference strain HF3. The CCoV-I and CCoV-II strains exhibited genetic diversity when compared with reference strains from China and other countries. The 57 CCoV strains exhibited high co-infection rates with canine kobuvirus (CaKV) (33.33%) and canine parvovirus-2 (CPV-2) (31.58%). The CCoV prevalence in diarrheic dogs differed significantly with immunization status, regions, seasons, and ages. Moreover, 28 S genes were amplified from the 57 CCoV-positive samples, including 26 CCoV-IIa strains, one CCoV-IIb strain, and one CCoV-I strain. A sequence comparison of the partial S gene revealed 86.3%-100% nucleotide identity among the 26 CCoV-IIa strains, and 89.6%-92.2% identity between the 26 CCoV-IIa strains and the Chinese reference strain V1. The 26 CCoV-IIa strains showed genetic diversity when compared with reference strains from China and other countries. Our data provide evidence that CCoV-I, CCoV-IIa, and CCoV-IIb strains co-circulate in the diarrhoetic dogs in northeast China, high co-infection rates with CaKV and CPV-2 were observed, and the CCoV-II strains exhibited high prevalence and genetic diversity. PMID:26771312

  1. Effects of salvianolic acid B and tanshinone IIA on the pharmacokinetics of losartan in rats by regulating the activities and expression of CYP3A4 and CYP2C9.

    Science.gov (United States)

    Wang, Rong; Zhang, Hai; Wang, Yujie; Yu, Xiaoyan; Yuan, Yongfang

    2016-03-01

    Losartan (LST) is a common chemical drug used to treat high blood pressure and reduce the risk of stroke in certain people with heart disease. Danshen, prepared from the dried root and rhizome of Salvia miltiorrhiza Bunge, has been widely used for prevention and treatment of various cardiovascular and cerebrovascular diseases. There are more than 35 formulations containing Danshen indexed in the 2010 Chinese Pharmacopoeia, which are often combined with LST to treat cardiovascular and cerebrovascular diseases in the clinic. The effects of the two major components of Danshen, salvianolic acid B (SA-B) and tanshinone IIA (Tan IIA), on the pharmacokinetics of losartan and its metabolite, EXP3174, in rats were investigated by liquid chromatography coupled with mass spectrometry (LC-MS). Male Sprague-Dawley rats were randomly assigned to 3 groups: LST, LST+SA-B and LST+Tan IIA, and the main pharmacokinetic parameters were estimated after oral administration of LST, LST+SA-B and LST+Tan IIA. It was found that there are significant differences in the pharmacokinetic parameters among the three groups: Cmax, t1/2, AUC, AUMC in the LST+SA-B group was smaller than those in group LST, while larger in group LST+Tan IIA. Further, the effects of SA-B and Tan IIA on the metabolism of losartan was also investigated using rat liver microsomes in vitro. The results indicated that SA-B can induce the metabolism of LST, while Tan IIA can inhibit the metabolism of LST in rat liver microsomes in vitro by regulating activities of CYP450 enzymes. In addition, the effect of SA-B and Tan IIA on CYP3A4 and CYP2C9 expression was studied in Chang liver cells by western-blotting and Real-time PCR. It was concluded that the two components of Danshen, SA-B and Tan IIA have different influences on the metabolism of LST: SA-B can obviously speed up the metabolism of LST by inducing CYP3A4/CYP2C9 activities and expression, however, Tan IIA can slow down the metabolism of LST by inhibiting CYP3A4/CYP2C

  2. Semantic Analysis of Virtual Classes and Nested Classes

    DEFF Research Database (Denmark)

    Madsen, Ole Lehrmann

    1999-01-01

    Virtual classes and nested classes are distinguishing features of BETA. Nested classes originated from Simula, but until recently they have not been part of main stream object- oriented languages. C++ has a restricted form of nested classes and they were included in Java 1.1. Virtual classes is the...... classes and parameterized classes have been made. Although virtual classes and nested classes have been used in BETA for more than a decade, their implementation has not been published. The purpose of this paper is to contribute to the understanding of virtual classes and nested classes by presenting the...

  3. Class network routing

    Science.gov (United States)

    Bhanot, Gyan; Blumrich, Matthias A.; Chen, Dong; Coteus, Paul W.; Gara, Alan G.; Giampapa, Mark E.; Heidelberger, Philip; Steinmacher-Burow, Burkhard D.; Takken, Todd E.; Vranas, Pavlos M.

    2009-09-08

    Class network routing is implemented in a network such as a computer network comprising a plurality of parallel compute processors at nodes thereof. Class network routing allows a compute processor to broadcast a message to a range (one or more) of other compute processors in the computer network, such as processors in a column or a row. Normally this type of operation requires a separate message to be sent to each processor. With class network routing pursuant to the invention, a single message is sufficient, which generally reduces the total number of messages in the network as well as the latency to do a broadcast. Class network routing is also applied to dense matrix inversion algorithms on distributed memory parallel supercomputers with hardware class function (multicast) capability. This is achieved by exploiting the fact that the communication patterns of dense matrix inversion can be served by hardware class functions, which results in faster execution times.

  4. Fostering a Middle Class

    Institute of Scientific and Technical Information of China (English)

    YAO BIN

    2011-01-01

    Though there is no official definition of "middle class" in China,the tag has become one few Chinese people believe they deserve anyway.In early August,the Chinese Academy of Social Sciences released a report on China's urban development,saying China had a middle-class population of 230 million in 2009,or 37 percent of its urban residents.It also forecast half of city dwellers in China would be part of the middle class by 2023.

  5. Tanshinone IIA Pretreatment Renders Free Flaps against Hypoxic Injury through Activating Wnt Signaling and Upregulating Stem Cell-Related Biomarkers

    Directory of Open Access Journals (Sweden)

    Zihan Xu

    2014-10-01

    Full Text Available Partial or total flap necrosis after flap transplantation is sometimes clinically encountered in reconstructive surgery, often as a result of a period of hypoxia that exceeds the tolerance of the flap tissue. In this study, we determine whether tanshinone IIA (TSA pretreatment can protect flap tissue against hypoxic injury and improve its viability. Primary epithelial cells isolated from the dorsal skin of mice were pretreated with TSA for two weeks. Cell counting kit-8 and Trypan Blue assays were carried out to examine the proliferation of TSA-pretreated cells after exposure to cobalt chloride. Then, Polymerase chain reaction and Western blot analysis were used to determine the expression of β-catenin, GSK-3β, SOX2, and OCT4 in TSA-treated cells. In vivo, after mice were pretreated with TSA for two weeks, a reproducible ischemic flap model was implemented, and the area of surviving tissue in the transplanted flaps was measured. Immunohistochemistry was also conducted to examine the related biomarkers mentioned above. Results show that epidermal cells, pretreated with TSA, showed enhanced resistance to hypoxia. Activation of the Wnt signaling pathway in TSA-pretreated cells was characterized by the upregulation of β-catenin and the downregulation of GSK-3β. The expression of SOX2 and OCT4 controlled by Wnt signaling were also found higher in TSA pretreated epithelial cells. In the reproducible ischaemic flap model, pretreatment with TSA enhanced resistance to hypoxia and increased the area of surviving tissue in transplanted flaps. The expression of Wnt signaling pathway components, stem-cell related biomarkers, and CD34, which are involved in the regeneration of blood vessels, was also upregulated in TSA-pretreated flap tissue. The results show that TSA pretreatment protects free flaps against hypoxic injury and increases the area of surviving tissue by activating Wnt signaling and upregulating stem cell-related biomarkers.

  6. TanshinoneIIA and cryptotanshinone protect against hypoxia-induced mitochondrial apoptosis in H9c2 cells.

    Directory of Open Access Journals (Sweden)

    Hyou-Ju Jin

    Full Text Available Mitochondrial apoptosis pathway is an important target of cardioprotective signalling. Tanshinones, a group of major bioactive compounds isolated from Salvia miltiorrhiza, have been reported with actions against inflammation, oxidative stress, and myocardial ischemia reperfusion injury. However, the actions of these compounds on the chronic hypoxia-related mitochondrial apoptosis pathway have not been investigated. In this study, we examined the effects and molecular mechanisms of two major tanshonones, tanshinone IIA (TIIA and cryptotanshinone (CT on hypoxia induced apoptosis in H9c2 cells. Cultured H9c2 cells were treated with TIIA and CT (0.3 and 3 μΜ 2 hr before and during an 8 hr hypoxic period. Chronic hypoxia caused a significant increase in hypoxia inducible factor 1α expression and the cell late apoptosis rate, which was accompanied with an increase in caspase 3 activity, cytochrome c release, mitochondria membrane potential and expression of pro-apoptosis proteins (Bax and Bak. TIIA and CT (0.3 and 3 μΜ, in concentrations without affecting the cell viability, significantly inhibited the late apoptosis and the changes of caspase 3 activity, cytochrome c release, and mitochondria membrane potential induced by chronic hypoxia. These compounds also suppressed the overexpression of Bax and reduced the ratio of Bax/Bcl-2. The results indicate that TIIA and CT protect against chronic hypoxia induced cell apoptosis by regulating the mitochondrial apoptosis signaling pathway, involving inhibitions of mitochondria hyperpolarization, cytochrome c release and caspase 3 activity, and balancing anti- and pro-apoptotic proteins in Bcl-2 family proteins.

  7. New laser classes

    International Nuclear Information System (INIS)

    By an up-dated international standard (IEC 60825-1 + Amendment 2) on laser safety some new laser classes are introduced. The new set of laser classes consists of 1, 1M, 2, 2M, 3R, 3B, and 4. This is a result of intense discussions in the committee and was laid down in 2000, slightly adjusted 2001. The previous classes 1, 2, 3A, 3B, and 4, established since more than 25 years, are partly abandoned. This paper compares the new classes to the old ones. (orig.)

  8. Class, Culture and Politics

    DEFF Research Database (Denmark)

    Harrits, Gitte Sommer

    2013-01-01

    , discussions within political sociology have not yet utilized the merits of a multidimensional conception of class. In light of this, the article suggests a comprehensive Bourdieusian framework for class analysis, integrating culture as both a structural phenomenon co-constitutive of class and as symbolic...... practice. Further, the article explores this theoretical framework in a multiple correspondence analysis of a Danish survey, demonstrating how class and political practices are indeed homologous. However, the analysis also points at several elements of field autonomy, and the concluding discussion...

  9. Comparative evaluation of microleakage in class II cavities restored with Ceram X and Filtek P-90: An in vitro study

    Directory of Open Access Journals (Sweden)

    Poonam Bogra

    2012-01-01

    Full Text Available Context: Polymerization shrinkage in composite resins is responsible for microleakage. Methacrylate-based composite resins have linear reactive groups resulting in high polymerization shrinkage. A recently introduced composite resin Filtek P90 is based on siloxanes and oxiranes which polymerize by cationic "ring opening" polymerization resulting in reduced polymerization shrinkage. Objectives: Aim of this study was to compare microleakage in class II cavities restored with a nanoceramic restorative (Ceram X and a silorane composite (Filtek P90. Materials and Methods: Standardized class II box type cavities were prepared on mesial (Groups Ia and IIa and distal (Groups Ib and IIb surfaces of twenty extracted permanent molar teeth with gingival floor ending 1 mm coronal and apical to the cementoenamel junction, respectively. The teeth in Group Ia and Ib were restored with Ceram X and Group IIa and IIb with Filtek P90. The specimens were thermocycled and microleakage evaluated. Statistical Analysis Used: The data were statistically analyzed using Wilcoxon Signed-Rank test at the 0.05 level of significance. Results: Mean microleakage score of group la and lb was 1 ± 2.260 and 2.8 ± 1.229, respectively. And that of group Ila and llb was 0.2 ± .869 and 0.3 ± .588, respectively. When groups I and II were compared, results were statistically significant (P<0.05. Conclusion: It was concluded that silorane-based composite may be a better substitute for methacrylate-based composites.

  10. Cell-free supernatants obtained from fermentation of cheese whey hydrolyzates and phenylpyruvic acid by Lactobacillus plantarum as a source of antimicrobial compounds, bacteriocins, and natural aromas.

    Science.gov (United States)

    Rodríguez-Pazo, Noelia; Vázquez-Araújo, Laura; Pérez-Rodríguez, Noelia; Cortés-Diéguez, Sandra; Domínguez, José Manuel

    2013-10-01

    Cheese whey hydrolyzates supplemented with phenylpyruvic acid (PPA) and commercial nutrients can be efficiently metabolized by Lactobacillus plantarum CECT-221 to biosynthesize some compounds with attractive applications in the food market. The main metabolites of cell-free extracts were antimicrobial compounds such as phenyllactic acid (PLA) and lactic acid (LA). The production of PLA by L. plantarum CECT-221 was evaluated in the Man-Rogosa-Sharpe broth supplemented with two biosynthetic precursors: phenylalanine or PPA. Using 30.5 mM PPA, the microorganism increased sevenfold the concentration of PLA producing 16.4 mM PLA in 46 h. A concentration of 40 mM PPA was a threshold to avoid substrate inhibition. The biosynthesis of whey hydrolyzates as a carbon source was enhanced by fed-batch fermentation of PPA; the average productivity of PLA increased up to 45.4 ± 3.02 mM after 120 h with a product yield of 0.244 mM mM(-1); meanwhile, LA reached 26.1 ± 1.3 g L(-1) with a product yield of 0.72 g g(-1). Cell-free fed-batch extracts charged in wells showed bacteriocin activity with halos of 7.49 ± 1.44 mm in plates inoculated with Carnobacterium piscicola and antimicrobial activity against Staphylococcus aureus (11.54 ± 1.14 mm), Pseudomonas aeruginosa (10.17 ± 2.46 mm), Listeria monocytogenes (7.75 ± 1.31 mm), and Salmonella enterica (3.60 ± 1.52 mm). Additionally, the analysis of the volatile composition of the headspace of this cell-free extract revealed that L. plantarum is a potential producer for natural aromas, such as acetophenone, with high price in the market. This is the first report of PLA production from cheese whey and PPA. The extracts showed bacteriocin activity and potential to be applied as an antimicrobial in the elaboration of safer foods. PMID:23934083

  11. Teaching Large Evening Classes

    Science.gov (United States)

    Wambuguh, Oscar

    2008-01-01

    High enrollments, conflicting student work schedules, and the sheer convenience of once-a-week classes are pushing many colleges to schedule evening courses. Held from 6 to 9 pm or 7 to 10 pm, these classes are typically packed, sometimes with more than 150 students in a large lecture theater. How can faculty effectively teach, control, or even…

  12. Class in disguise

    DEFF Research Database (Denmark)

    Faber, Stine Thidemann; Prieur, Annick

    This paper asks how class can have importance in one of the worlds’ most equal societies: Denmark. The answer is that class here appears in disguised forms. The field under study is a city, Aalborg, in the midst of transition from a stronghold of industrialism to a post industrial economy...

  13. Teaching Social Class

    Science.gov (United States)

    Tablante, Courtney B.; Fiske, Susan T.

    2015-01-01

    Discussing socioeconomic status in college classes can be challenging. Both teachers and students feel uncomfortable, yet social class matters more than ever. This is especially true, given increased income inequality in the United States and indications that higher education does not reduce this inequality as much as many people hope. Resources…

  14. DEFINING THE MIDDLE CLASS

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Classifying the middle class remains controversial despite its alleged growth China’s cities housed more than 230 million middle-class residents in 2009 or 37 percent of the urban population,according to the 2011 Blue Book of Cities in China released on August 3.

  15. Activin receptor IIA ligand trap in chronic kidney disease: 1 drug to prevent 2 complications-or even more?

    Science.gov (United States)

    Massy, Ziad A; Drueke, Tilman B

    2016-06-01

    Vascular calcification and kidney fibrosis are 2 important features of chronic kidney disease. Bone morphogenetic proteins/growth differentiation factors and their receptors are implicated in the pathogenesis of both processes. Modulation of the bone morphogenetic protein/growth differentiation factor pathways by a soluble chimeric protein that contains the activin receptor IIA (ActRIIA) domain and acts as an ActRIIA ligand trap for activin and other ligands could become a new therapeutic strategy for vascular calcification and kidney fibrosis in chronic kidney disease. PMID:27181771

  16. Genetic variation in Fcγ receptor IIa and risk of coronary heart disease: negative results from two large independent populations

    OpenAIRE

    Khuseyinova Natalie; Winkelmann Bernhard; Meisinger Christa; Rothenbacher Dietrich; Vollmert Caren; Hoffmann Michael M; Karakas Mahir; Böhm Bernhard O; Illig Thomas; März Winfried; Koenig Wolfgang

    2009-01-01

    Abstract Background The role of the Fcγ receptor IIa (FcγRIIa), a receptor for C-reactive protein (CRP), the classical acute phase protein, in atherosclerosis is not yet clear. We sought to investigate the association of FcγRIIa genotype with risk of coronary heart disease (CHD) in two large population-based samples. Methods FcγRIIa-R/H131 polymorphisms were determined in a population of 527 patients with a history of myocardial infarction and 527 age and gender matched controls drawn from a ...

  17. The combined Mössbauer and XRF Spectrometer MIMOS IIA for In-Situ Geochemical and Mineralogical Analysis of Planetary Surfaces.

    Science.gov (United States)

    Klingelhoefer, Goestar; Morris, Richard; Blumers, Mathias; Girones-Lopez, Jordi; Bernhardt, Bodo; Henkel, Hartmut; D'Uston, Claude; Brueckner, Johannes; Rodionov, Daniel; Strueder, Lothar

    The Miniaturised Mössbauer Spectrometers MIMOS II on board the two NASA Mars Exploration Rovers (MER) have now collected valuable scientific data for more than ten years [1-4]. This mission has demonstrated that Mössbauer spectroscopy is extremely valuable for the in situ exploration of extraterrestrial bodies and the study of Fe-bearing samples. A MIMOS instrument was also on the scientific payload of the Russian mission Phobos Grunt [5]. The instrument MIMOS IIA originally developed for the ESA ExoMars mission (now 2018) will use newly de-signed Si-Drift detectors with circular geometry (SDD) [6,7] allowing high resolution X-ray fluorescence spectroscopy simultaneously to Mössbauer measurements. The new design of the improved MIMOS II instrument is reduced in total mass (less than 400 g). The sensorhead of MIMOS IIA will be equipped with a ring of Silicon Drift Detectors (SDD) optimized for the backscatter geometry of the miniaturized Mössbauer spectrometer. The main goal of the new detector system design was to combine high energy resolution at high counting rates and large detector area while making maximum use of the area close to the collimator of the 57Co Mössbauer source. The active area per SDD segment is 2x45 mm2. The energy resolution at 5.9 keV is elemental composition [7]. Preliminary studies at room temperature and normal pressure show detection of X-rays down to ~1 keV. A new control- and readout electronics for MIMOS IIA allows spectra acquisition at highest possible countrates available at about 360 mm2 total detector area. A prototype of MIMOS IIA has been tested successfully during a field test at Mauna Kea, Hawaii, as part of the international NASA JSC lead In-Situ Resource Utilization field tests 2010 and 2012. Acknowledgment: Funded by german space agency DLR under contract 50 QX 0603 and 50QX0802. References: [1] Klingelhöfer et al., J. Geophys. Res. 108(E12) (2003) [2] Klingelhöfer et al., Science 306 (2004) 1740-1745. [3] Morris et

  18. Radioactive waste disposal implications of extending Part IIA of the Environmental Protection Act to cover radioactively contaminated land.

    Science.gov (United States)

    Nancarrow, D J; White, M M

    2004-03-01

    A short study has been carried out of the potential radioactive waste disposal issues associated with the proposed extension of Part IIA of the Environmental Protection Act 1990 to include radioactively contaminated land, where there is no other suitable existing legislation. It was found that there is likely to be an availability problem with respect to disposal at landfills of the radioactive wastes arising from remediation. This is expected to be principally wastes of high volume and low activity (categorised as low level waste (LLW) and very low level waste (VLLW)). The availability problem results from a lack of applications by landfill operators for authorisation to accept LLW wastes for disposal. This is apparently due to perceived adverse publicity associated with the consultation process for authorisation coupled with uncertainty over future liabilities. Disposal of waste as VLLW is limited both by questions over volumes that may be acceptable and, more fundamentally, by the likely alpha activity of wastes (originating from radium and thorium operations). Authorised on-site disposal has had little attention in policy and guidance in recent years, but may have a part to play, especially if considered commercially attractive. Disposal at BNFL's near surface disposal facility for LLW at Drigg is limited to wastes for which there are no practical alternative disposal options (and preference has been given to operational type wastes). Therefore, wastes from the radioactively contaminated land (RCL) regime are not obviously attractive for disposal to Drigg. Illustrative calculations have been performed based on possible volumes and activities of RCL arisings (and assuming Drigg's future volumetric disposal capacity is 950,000 m3). These suggest that wastes arising from implementing the RCL regime, if all disposed to Drigg, would not represent a significant fraction of the volumetric capacity of Drigg, but could have a significant impact on the radiological

  19. Radioactive waste disposal implications of extending Part IIA of the Environmental Protection Act to cover radioactively contaminated land

    International Nuclear Information System (INIS)

    A short study has been carried out of the potential radioactive waste disposal issues associated with the proposed extension of Part IIA of the Environmental Protection Act 1990 to include radioactively contaminated land, where there is no other suitable existing legislation. It was found that there is likely to be an availability problem with respect to disposal at landfills of the radioactive wastes arising from remediation. This is expected to be principally wastes of high volume and low activity (categorised as low level waste (LLW) and very low level waste (VLLW)). The availability problem results from a lack of applications by landfill operators for authorisation to accept LLW wastes for disposal. This is apparently due to perceived adverse publicity associated with the consultation process for authorisation coupled with uncertainty over future liabilities. Disposal of waste as VLLW is limited both by questions over volumes that may be acceptable and, more fundamentally, by the likely alpha activity of wastes (originating from radium and thorium operations). Authorised on-site disposal has had little attention in policy and guidance in recent years, but may have a part to play, especially if considered commercially attractive. Disposal at BNFL's near surface disposal facility for LLW at Drigg is limited to wastes for which there are no practical alternative disposal options (and preference has been given to operational type wastes). Therefore, wastes from the radioactively contaminated land (RCL) regime are not obviously attractive for disposal to Drigg. Illustrative calculations have been performed based on possible volumes and activities of RCL arisings (and assuming Drigg's future volumetric disposal capacity is 950 000 m3). These suggest that wastes arising from implementing the RCL regime, if all disposed to Drigg, would not represent a significant fraction of the volumetric capacity of Drigg, but could have a significant impact on the radiological

  20. Radioactive waste disposal implications of extending Part IIA of the Environmental Protection Act to cover radioactively contaminated land

    Energy Technology Data Exchange (ETDEWEB)

    Nancarrow, D J; White, M M [Atkins Environment, Woodcote Grove, Ashley Road, Epsom KT18 5BW (United Kingdom)

    2004-03-01

    A short study has been carried out of the potential radioactive waste disposal issues associated with the proposed extension of Part IIA of the Environmental Protection Act 1990 to include radioactively contaminated land, where there is no other suitable existing legislation. It was found that there is likely to be an availability problem with respect to disposal at landfills of the radioactive wastes arising from remediation. This is expected to be principally wastes of high volume and low activity (categorised as low level waste (LLW) and very low level waste (VLLW)). The availability problem results from a lack of applications by landfill operators for authorisation to accept LLW wastes for disposal. This is apparently due to perceived adverse publicity associated with the consultation process for authorisation coupled with uncertainty over future liabilities. Disposal of waste as VLLW is limited both by questions over volumes that may be acceptable and, more fundamentally, by the likely alpha activity of wastes (originating from radium and thorium operations). Authorised on-site disposal has had little attention in policy and guidance in recent years, but may have a part to play, especially if considered commercially attractive. Disposal at BNFL's near surface disposal facility for LLW at Drigg is limited to wastes for which there are no practical alternative disposal options (and preference has been given to operational type wastes). Therefore, wastes from the radioactively contaminated land (RCL) regime are not obviously attractive for disposal to Drigg. Illustrative calculations have been performed based on possible volumes and activities of RCL arisings (and assuming Drigg's future volumetric disposal capacity is 950 000 m{sup 3}). These suggest that wastes arising from implementing the RCL regime, if all disposed to Drigg, would not represent a significant fraction of the volumetric capacity of Drigg, but could have a significant impact on the

  1. Partial Purification and Characterization of the Mode of Action of Enterocin S37: A Bacteriocin Produced by Enterococcus faecalis S37 Isolated from Poultry Feces

    Directory of Open Access Journals (Sweden)

    Y. Belguesmia

    2010-01-01

    Full Text Available The aim of this research was to purify and characterize the mode of action of enterocin S37, a bacteriocin produced by Enterococcus faecalis S37, a strain recently isolated from the chicken feces. Enterocin S37 has a molecular weight comprised between 4 and 5 kDa. It remained active after 1 h at 80oC and at pH values ranging from 4.0 to 9.0. Furthermore, cell-free supernatant of Enterococcus faecalis S37 and purified enterocin S37 were active against Gram-positive bacteria including Listeria monocytogenes EGDe, L. innocua F, Enterococcus faecalis JH2-2, and Lactobacillus brevis F145. The purification of enterocin S37 was performed by ammonium sulfate precipitation followed up by hydrophobic-interaction chromatography procedures. Treatment of enterocin S37 with proteinase K, -chymotrypsin, and papain confirmed its proteinaceous nature, while its treatment with lysozyme and lipase resulted in no alteration of activity. Enterocin S37 is hydrophobic, anti-Listeria and likely acting by depletion of intracellular K+ ions upon action on KATP channels. This study contributed to gain more insights into the mode of action of enterocins.

  2. Isolation and Identification of Lactobacilli From Cheese, Yoghurt and Silage by 16S rDNA Gene and Study of Bacteriocin and Biosurfactant Production

    Directory of Open Access Journals (Sweden)

    Sharareh Peymanfar

    2012-09-01

    Full Text Available Background: Background: The Lactobacilli belong to lactic acid bacteria, whose primary fermentation end product from sugars is lactic acid and that is why foods are conserved. Lactic acid bacteria have been used for millennia in the production of silage. Therefore, they are an indispensable part of intestinal microflora in human and animals. .Objectives: This research meant to isolate lactic acid bacteria with significant effects from different environments. .Materials and Methods: In this study, heterofermentative LAB were isolated from cheese, yoghurt and corn silage in Broujerd ,Iran. The standard biochemical methods were applied. Acid tolerance was studied by exposure to acidic PBS and growth in bile salt was measured by the spectrophotometric method. The isolated bacteria were studied for antagonistic effects on environment isolated E.coli, bacteriocin and biosurfactant production. Bacterial DNA was extracted, and amplified by PCR method. .Results: The 3 isolates from cheese, yoghurt and silage were effective against isolated E.coli and could produce biosurfactants. Phylogenic relationships of the 3 potential candidates were determined comparing the 16Sr DNA gene sequences, they were found to be as 3 isolates of Lactobacillus buchneri, L.brevis and L.kefiri that were effective on the isolated E.coli from environment. .Conclusions: It was found that the isolated bacteria produced biosurfactants that had a great potential for different industries.

  3. Genomic and Proteomic Characterization of Bacteriocin-Producing Leuconostoc mesenteroides Strains Isolated from Raw Camel Milk in Two Southwest Algerian Arid Zones

    Science.gov (United States)

    Benmechernene, Zineb; Fernández-No, Inmaculada; Quintela-Baluja, Marcos; Kihal, Mebrouk; Calo-Mata, Pilar; Barros-Velázquez, Jorge

    2014-01-01

    Information on the microbiology of camel milk is very limited. In this work, the genetic characterization and proteomic identification of 13 putative producing bacteriocin Leuconostoc strains exhibiting antilisterial activity and isolated from camel milk were performed. DNA sequencing of the 13 selected strains revealed high homology among the 16S rRNA genes for all strains. In addition, 99% homology with Leuconostoc mesenteroides was observed when these sequences were analysed by the BLAST tool against other sequences from reference strains deposited in the Genbank. Furthermore, the isolates were characterized by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDITOF MS) which allowed for the identification of 2 mass peaks 6242 m/z and 5118 m/z that resulted to be specific to the species L. mesenteroides. Remarkably, the phyloproteomic tree provided more intraspecific information of L. mesenteroides than phylogenetic analysis. Accordingly, phyloproteomic analysis grouped L. mesenteroides strains into different subbranches, while all L. mesenteroides isolates were grouped in the same branch according to phylogenetic analysis. This study represents, to our knowledge, the first report on the use of MALDI-TOF MS on the identification of LAB isolated from camel milk. PMID:24809059

  4. Genomic and Proteomic Characterization of Bacteriocin-Producing Leuconostoc mesenteroides Strains Isolated from Raw Camel Milk in Two Southwest Algerian Arid Zones

    Directory of Open Access Journals (Sweden)

    Zineb Benmechernene

    2014-01-01

    Full Text Available Information on the microbiology of camel milk is very limited. In this work, the genetic characterization and proteomic identification of 13 putative producing bacteriocin Leuconostoc strains exhibiting antilisterial activity and isolated from camel milk were performed. DNA sequencing of the 13 selected strains revealed high homology among the 16S rRNA genes for all strains. In addition, 99% homology with Leuconostoc mesenteroides was observed when these sequences were analysed by the BLAST tool against other sequences from reference strains deposited in the Genbank. Furthermore, the isolates were characterized by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDITOF MS which allowed for the identification of 2 mass peaks 6242 m/z and 5118 m/z that resulted to be specific to the species L. mesenteroides. Remarkably, the phyloproteomic tree provided more intraspecific information of L. mesenteroides than phylogenetic analysis. Accordingly, phyloproteomic analysis grouped L. mesenteroides strains into different subbranches, while all L. mesenteroides isolates were grouped in the same branch according to phylogenetic analysis. This study represents, to our knowledge, the first report on the use of MALDI-TOF MS on the identification of LAB isolated from camel milk.

  5. Genomic and proteomic characterization of bacteriocin-producing Leuconostoc mesenteroides strains isolated from raw camel milk in two southwest Algerian arid zones.

    Science.gov (United States)

    Benmechernene, Zineb; Fernández-No, Inmaculada; Quintela-Baluja, Marcos; Böhme, Karola; Kihal, Mebrouk; Calo-Mata, Pilar; Barros-Velázquez, Jorge

    2014-01-01

    Information on the microbiology of camel milk is very limited. In this work, the genetic characterization and proteomic identification of 13 putative producing bacteriocin Leuconostoc strains exhibiting antilisterial activity and isolated from camel milk were performed. DNA sequencing of the 13 selected strains revealed high homology among the 16S rRNA genes for all strains. In addition, 99% homology with Leuconostoc mesenteroides was observed when these sequences were analysed by the BLAST tool against other sequences from reference strains deposited in the Genbank. Furthermore, the isolates were characterized by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDITOF MS) which allowed for the identification of 2 mass peaks 6242 m/z and 5118 m/z that resulted to be specific to the species L. mesenteroides. Remarkably, the phyloproteomic tree provided more intraspecific information of L. mesenteroides than phylogenetic analysis. Accordingly, phyloproteomic analysis grouped L. mesenteroides strains into different subbranches, while all L. mesenteroides isolates were grouped in the same branch according to phylogenetic analysis. This study represents, to our knowledge, the first report on the use of MALDI-TOF MS on the identification of LAB isolated from camel milk. PMID:24809059

  6. Carbon dioxide stimulates the production of amylovorin L by Lactobacillus amylovorus DCE 471, while enhanced aeration causes biphasic kinetics of growth and bacteriocin production.

    Science.gov (United States)

    Neysens, Patricia; De Vuyst, Luc

    2005-11-25

    The effects of both oxygen and carbon dioxide on growth of and product formation by Lactobacillus amylovorus DCE 471, a promising new sourdough starter culture, were assessed through controlled, in vitro fermentation experiments, using a temperature of 37 degrees C and a constant pH of 5.4. It was seen that aeration affected both cell growth and amylovorin L production. At aeration rates of 1 l min(-1) and more, the bacterial population was subjected to oxidative stress as reflected by biphasic growth patterns. During the first growth phase, the maximum specific growth rate increased with increasing aeration rates stabilizing at the highest oxygen concentrations. The maximum obtainable cell yields decreased. During the second growth phase, the amylovorin L production was stimulated at the highest aeration. However, amylovorin titers were never higher in the presence of oxygen compared with the anaerobic fermentations. Carbon dioxide did not influence cell growth of L. amylovorus DCE 471. The maximum specific growth rate and the biomass concentrations were merely affected. On the other hand, the maximum soluble bacteriocin titers coincided with the highest carbon dioxide flow rates. These results indicate that mild aeration of type II sourdoughs might enhance both cell yield and amylovorin L production by L. amylovorus DCE 471, thereby contributing to the competitiveness of the strain. Growth in an ecosystem together with yeasts producing carbon dioxide might exert a positive effect on the production of amylovorin L as well. PMID:16087265

  7. Social Class Dialogues and the Fostering of Class Consciousness

    Science.gov (United States)

    Madden, Meredith

    2015-01-01

    How do critical pedagogies promote undergraduate students' awareness of social class, social class identity, and social class inequalities in education? How do undergraduate students experience class consciousness-raising in the intergroup dialogue classroom? This qualitative study explores undergraduate students' class consciousness-raising in an…

  8. Teaching Heterogeneous Classes.

    Science.gov (United States)

    Millrood, Radislav

    2002-01-01

    Discusses an approach to teaching heterogeneous English-as-a-Second/Foreign-Language classes. Draws on classroom research data to describe the features of a success-building lesson context. (Author/VWL)

  9. IELP Class Observation

    Institute of Scientific and Technical Information of China (English)

    陈了了

    2010-01-01

    @@ As an exchange student majoring in English, I am curious about how English is taught to international students here in America. Therefore, I observed an IELP (Intensive English Learning Program) class in Central Connecticut State University where I study.

  10. PSYCH 515 Complete Class

    OpenAIRE

    admin

    2015-01-01

      PSYCH 515 Advanced Abnormal Psychology To purchase this material click on below link http://www.assignmentcloud.com/PSYCH-515/PSYCH-515-Complete-Class-Guide For more details www.assignmentcloud.com

  11. Raradox of class description

    Institute of Scientific and Technical Information of China (English)

    吕光

    2004-01-01

    We have a more active class atmophere, but more passive self-study situations. We are too talktive when we should bury ourselves in books, but too less efficient when we spend too much time. We complain teachers

  12. Nordic Walking Classes

    CERN Multimedia

    Fitness Club

    2015-01-01

    Four classes of one hour each are held on Tuesdays. RDV barracks parking at Entrance A, 10 minutes before class time. Spring Course 2015: 05.05/12.05/19.05/26.05 Prices 40 CHF per session + 10 CHF club membership 5 CHF/hour pole rental Check out our schedule and enroll at: https://espace.cern.ch/club-fitness/Lists/Nordic%20Walking/NewForm.aspx? Hope to see you among us! fitness.club@cern.ch

  13. Embodying class and gender

    OpenAIRE

    Geers, Alexie

    2015-01-01

    In March 1937, when the first issue of Marie-Claire was published, the images of the female body it presented to its female readers from working-class backgrounds contrasted sharply with those featured in previous magazines. The female bodies are dressed and groomed to seduce and replace the hieratic bodies that presented fashions synonymous with membership in the upper classes. The present essay examines this shift and shows that the visual repertoire employed is borrowed from that of the fe...

  14. Generalized Fourier transforms classes

    DEFF Research Database (Denmark)

    Berntsen, Svend; Møller, Steen

    2002-01-01

    The Fourier class of integral transforms with kernels $B(\\omega r)$ has by definition inverse transforms with kernel $B(-\\omega r)$. The space of such transforms is explicitly constructed. A slightly more general class of generalized Fourier transforms are introduced. From the general theory foll...... follows that integral transform with kernels which are products of a Bessel and a Hankel function or which is of a certain general hypergeometric type have inverse transforms of the same structure....

  15. Detection of HTLV-IIa in blood donors in an urban area of the Amazon Region of Brazil (Belém, PA

    Directory of Open Access Journals (Sweden)

    Ishak R.

    1998-01-01

    Full Text Available The human lymphotropic viruses type I (HTLV-I and type II (HTLV-II are members of a group of mammalian retroviruses with similar biological properties, and blood transfusion is an important route of transmission. HTLV-I is endemic in a number of different geographical areas and is associated with several clinical disorders. HTLV-II is endemic in several Indian groups of the Americas and intravenous drug abusers in North and South America, Europe and Southeast Asia. During the year of 1995, all blood donors tested positive to HTLV-I/II in the State Blood Bank (HEMOPA, were directed to a physician and to the Virus Laboratory at the Universidade Federal do Pará for counselling and laboratory diagnosis confirmation. Thirty-five sera were tested by an enzyme immune assay, and a Western blot that discriminates HTLV-I and HTLV-II infection. Two HTLV-II positive samples were submitted to PCR analysis of pX and env genomic region, and confirmed to be of subtype IIa. This is the first detection in Belém of the presence of HTLV-IIa infection among blood donors. This result emphasizes that HTLV-II is also present in urban areas of the Amazon region of Brazil and highlights the need to include screening tests that are capable to detect antibodies for both types of HTLV.

  16. Single Photon Emission Computed Tomography (SPECT) Experience with (S)-5-[123I]iodo-3-(2-azetidinylmethoxy)pyridine (5-[123I]IA) in the Living Human Brain of Smokers and Nonsmokers

    OpenAIRE

    BRAŠIĆ, JAMES ROBERT; Zhou, Yun; MUSACHIO, JOHN L.; Hilton, John; Fan, Hong; CRABB, ANDREW; Endres, Christopher J.; REINHARDT, MELVIN J.; DOGAN, AHMET S.; Alexander, Mohab; Rousset, Olivier; MARIS, MARIKA A.; GALECKI, JEFFREY; Nandi, Ayon; Wong, Dean F.

    2009-01-01

    (S)-5-[123I]iodo-3-(2-azetidinylmethoxy)pyridine (5-[123I]IA), a novel potent radioligand for high-affinity α4β2* neuronal nicotinic acetylcholine receptors (nAChRs), provides a means to evaluate the density and the distribution of nAChRs in the living human brain. We sought in healthy adult smokers and nonsmokers to (1) evaluate the safety, tolerability, and efficacy of 5-[123I]IA in an open nonblind trial and (2) to estimate the density and distribution of α4β2* nAChRs in the brain. Single ...

  17. Study on Biofilm Inhibit Mechanism of Streptococcus Sanguis Bacteriocin on Candida Albicans.%血链球菌细菌素对白色念珠菌生物膜抑制作用的研究

    Institute of Scientific and Technical Information of China (English)

    马晟利; 王琪波; 李旭明

    2011-01-01

    Objective: To extract bacteriocin effective antimicrobial substances the standard strains of Streptococcus sanguis ATCC10556 and to study the action mechanism of Streptococcus sanguis bacteriocin on Candida albicans biofilms. Methods.. By ultrasonic, salt precipitation and sephadex G-25 column desalting through dialysis, sanguicin of the streptococcus bacteria isolated elements, the Candida albicans biofilms. After 2h, 6h, 12h, 24h, 48h, 72h,changes observed in BF. Results: After 24h, Candida albicans biofilms changed significantly, then was 12h. Conclusion: Streptococcus sanguis bacteriocin biofilms of Candida albicans strains were significantly inhibited.%目的:提取血链球菌标准株ATCC10556的有效抗菌物质细菌素,进一步研究血链球菌细菌素对白色念珠菌生物膜的作用机理.方法:通过超声破碎、盐析、sephadex G-25过柱脱盐、透析、浓缩的方法分离血链球菌细菌素,使之作用于白色念珠菌生物膜,并在2 h、6 h、12 h、24 h、48 h、72 h观察白色念珠菌生物膜厚度的变化.结果:24 h内白色念珠菌生物膜厚度有明显改变,12 h效果最为显著.结论:血链球菌细菌素对白色念株菌生物膜具有显著的抑制作用.

  18. theories of class

    Science.gov (United States)

    Gaiotto, Davide; Razamat, Shlomo S.

    2015-07-01

    We construct classes of superconformal theories elements of which are labeled by punctured Riemann surfaces. Degenerations of the surfaces correspond, in some cases, to weak coupling limits. Different classes are labeled by two integers ( N, k). The k = 1 case coincides with A N - 1 theories of class and simple examples of theories with k > 1 are orbifolds of some of the A N - 1 class theories. For the space of theories to be complete in an appropriate sense we find it necessary to conjecture existence of new strongly coupled SCFTs. These SCFTs when coupled to additional matter can be related by dualities to gauge theories. We discuss in detail the A 1 case with k = 2 using the supersymmetric index as our analysis tool. The index of theories in classes with k > 1 can be constructed using eigenfunctions of elliptic quantum mechanical models generalizing the Ruijsenaars-Schneider integrable model. When the elliptic curve of the model degenerates these eigenfunctions become polynomials with coefficients being algebraic expressions in fugacities, generalizing the Macdonald polynomials with rational coefficients appearing when k = 1.

  19. Influence of bacteriocins produced by Lactobacillus plantarum BN in the shelf-life of refrigerated bovine meat Influência de bacteriocinas produzidas por Lactobacillus plantarum BN na vida útil de carne bovina refrigerada

    OpenAIRE

    Ângela M. Fiorentini; Ernani S. Sant'Anna; Anna C.S. Porto; Jaciara Z. Mazo; Franco, Bernadette D.G.M.

    2001-01-01

    Sugar cane molasses is a cheap by-product of the sugar cane industry. This product was used for growth and production of bacteriocins by Lactobacillus plantarum BN and evaluated for its potential application in the extension of the shelf-life of raw meat. Bovine meat cubes were dipped in the filtered and neutralized supernatant of the fermented broth (Treatment A) and stored at 5ºC. Counts of psychrotrophic and mesophilic aerobic microorganisms, pH determination and total acidity were perform...

  20. Does class attendance still matter?

    OpenAIRE

    Abel Nyamapfene

    2010-01-01

    This paper presents a study on the impact of class attendance on academic performance in a second year Electronics Engineering course module with online notes and no mandatory class attendance policy. The study shows that class attendance is highly correlated to academic performance, despite the availability of online class notes. In addition, there is significant correlation between class attendance and non-class contact with the lecturer and between student performance in the first year of ...