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Sample records for 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. 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...

  3. 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.

  4. 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

  5. Bacteriocins as potential anticancer agents

    Directory of Open Access Journals (Sweden)

    Sukhraj eKaur

    2015-11-01

    Full Text Available Cancer remains one of the leading causes of deaths worldwide, despite advances in its treatment and detection. The conventional chemotherapeutic agents used for the treatment of cancer have nonspecific toxicity towards normal body cells that cause various side effects. Secondly, cancer cells are known to develop chemotherapy resistance in due course of treatment. Thus, the demand for novel anti-cancer agents is increasing day by day. Some of the experimental studies have reported the therapeutic potential of bacteriocins against various types of cancer cell lines. Bacteriocins are ribosomally-synthesized cationic peptides secreted by almost all groups of bacteria. Some bacteriocins have shown selective cytotoxicity towards cancer cells as compared to normal cells. This makes them promising candidates for further investigation and clinical trials. In this review article, we present the overview of the various cancer cell-specific cytotoxic bacteriocins, their mode of action and efficacies.

  6. LACTOCOCCAL BACTERIOCINS - MODE OF ACTION AND IMMUNITY

    NARCIS (Netherlands)

    VENEMA, K; KOK, J; Venema, Gerhardus

    1995-01-01

    Bacteriocins are antimicrobial peptides produced by bacteria. Some of those synthesized by Lactococcus lactis have been characterized in great detail recently. The lactococcal bacteriocins are hydrophobic cationic peptides, which form pores in the cytoplasmic membrane of sensitive cells.

  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. Cloning of Two Bacteriocin Genes from a Lactococcal Bacteriocin Plasmid

    NARCIS (Netherlands)

    Belkum, Marco J. van; Hayema, Bert Jan; Geis, Arnold; Kok, Jan; Venema, Gerard

    1989-01-01

    Lactococcus lactis subsp. cremoris 9B4 plasmid p9B4-6 (60 kilobases [kb]), which specifies bacteriocin production and immunity, was analyzed with restriction endonucleases, and fragments of this plasmid were cloned into shuttle vectors based on the broad-host-range plasmid pWVO1. Two regions on p9B4

  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. 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...

  11. 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

  12. 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.

  13. 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

  14. 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.

  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. Bacteriocin production by Carnobacterium piscicola LV 61.

    Science.gov (United States)

    Schillinger, U; Stiles, M E; Holzapfel, W H

    1993-11-26

    Carnobacterium piscicola LV 61 produces a bacteriocin designated piscicolin 61, that is heat resistant, active over a wide pH range and inactivated by alpha-chymotrypsin, pepsin, trypsin and papain. It is effective against strains of the genera Carnobacterium, Enterococcus and Listeria. Other lactic acid bacteria tested were less sensitive or resistant to piscicolin. It is produced at temperatures from 1 to 30 degrees C. Maximum bacteriocin activity was detected after the culture had entered the stationary phase of growth and when the culture was grown in a medium with an initial pH between 8.0 and 9.0. The same high amounts of bacteriocin could be obtained in a culture at a constant pH of 6.5. No bacteriocin was produced at pH 5.0. Peptone in the growth medium promotes bacteriocin production, whereas meat and yeast extract did not influence the amounts of bacteriocin produced. Bacteriocin production and immunity are probably encoded by a 22 kb plasmid. PMID:8312140

  17. 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

  18. 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 ...

  19. 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...

  20. 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

  1. 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.

  2. 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

  3. Class IIa Bacteriocins: Diversity and New Developments

    Directory of Open Access Journals (Sweden)

    Yanhua Cui

    2012-12-01

    Full Text Available Class IIa bacteriocins are heat-stable, unmodified peptides with a conserved amino acids sequence YGNGV on their N-terminal domains, and have received much attention due to their generally recognized as safe (GRAS status, their high biological activity, and their excellent heat stability. They are promising and attractive agents that could function as biopreservatives in the food industry. This review summarizes the new developments in the area of class IIa bacteriocins and aims to provide uptodate information that can be used in designing future research.

  4. Bacteriocin-producing Enterococci from Rabbit Meat

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    Szabóová, R.

    2012-01-01

    Full Text Available 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 Enterococcus faecium by PCR method. The isolates have possessed the structural genes for enterocins A, P, B production. The inhibitory substances produced by the isolated enterococci inhibited the growth of 12 indicators. Of 34 isolates, 15 strains have shown the antimicrobial activity against L. monocytogenes CCM 4699, 12 strains against S. aureus 3A3, 10 strains against S. aureus 5A2 as well as Salmonella enterica serovar Enteritidis PT4. Moreover, enterococci have tolerated 5 % bile, low pH; they have produced lactid acid in the amount from 0.740 ± 0.091 to 1.720 ± 0.095 mmol/l. The isolates were mostly sensitive to antibiotics. Conclusion, significance and impact of study: Bacteriocin-producing strain E. faecium M3a has been selected for more detail characterization of its bacteriocin and probiotic properties with the aim for its further application as an additive.

  5. Cloning, Sequencing, and Expression in Escherichia coli of lcnB, a Third Bacteriocin Determinant from the Lactococcal Bacteriocin Plasmid p9B4-6

    NARCIS (Netherlands)

    Belkum, Marco J. van; 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 operon

  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. 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.

  8. 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

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

    Directory of Open Access Journals (Sweden)

    Kevin eEgan

    2016-04-01

    Full Text Available 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

  10. 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

  11. 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.

  12. 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

  13. Nanotechnology: A Valuable Strategy to Improve Bacteriocin Formulations

    Science.gov (United States)

    Fahim, Hazem A.; Khairalla, Ahmed S.; El-Gendy, Ahmed O.

    2016-01-01

    Bacteriocins are proteinaceous antibacterial compounds, produced by diverse bacteria, which have been successfully used as: (i) food biopreservative; (ii) anti-biofilm agents; and (iii) additives or alternatives to the currently existing antibiotics, to minimize the risk of emergence of resistant strains. However, there are several limitations that challenge the use of bacteriocins as biopreservatives/antibacterial agents. One of the most promising avenues to overcome these limitations is the use of nanoformulations. This review highlights the practical difficulties with using bacteriocins to control pathogenic microorganisms, and provides an overview on the role of nanotechnology in improving the antimicrobial activity and the physicochemical properties of these peptides.

  14. Nanotechnology: A Valuable Strategy to Improve Bacteriocin Formulations

    Science.gov (United States)

    Fahim, Hazem A.; Khairalla, Ahmed S.; El-Gendy, Ahmed O.

    2016-01-01

    Bacteriocins are proteinaceous antibacterial compounds, produced by diverse bacteria, which have been successfully used as: (i) food biopreservative; (ii) anti-biofilm agents; and (iii) additives or alternatives to the currently existing antibiotics, to minimize the risk of emergence of resistant strains. However, there are several limitations that challenge the use of bacteriocins as biopreservatives/antibacterial agents. One of the most promising avenues to overcome these limitations is the use of nanoformulations. This review highlights the practical difficulties with using bacteriocins to control pathogenic microorganisms, and provides an overview on the role of nanotechnology in improving the antimicrobial activity and the physicochemical properties of these peptides. PMID:27695440

  15. Bacteriocins of lactic acid bacteria: extending the family.

    Science.gov (United States)

    Alvarez-Sieiro, Patricia; Montalbán-López, Manuel; Mu, Dongdong; Kuipers, Oscar P

    2016-04-01

    Lactic acid bacteria (LAB) constitute a heterogeneous group of microorganisms that produce lactic acid as the major product during the fermentation process. LAB are Gram-positive bacteria with great biotechnological potential in the food industry. They can produce bacteriocins, which are proteinaceous antimicrobial molecules with a diverse genetic origin, posttranslationally modified or not, that can help the producer organism to outcompete other bacterial species. In this review, we focus on the various types of bacteriocins that can be found in LAB and the organization and regulation of the gene clusters responsible for their production and biosynthesis, and consider the food applications of the prototype bacteriocins from LAB. Furthermore, we propose a revised classification of bacteriocins that can accommodate the increasing number of classes reported over the last years.

  16. 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.

  17. 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

  18. MOLECULAR PROFILING AND ANTIMICROBIAL ACTIVITY OF BACTERIOCIN FROM BACILLUS SUBTILIS

    Directory of Open Access Journals (Sweden)

    Berlina Dhas S

    2012-12-01

    Full Text Available Development of multi drug resistant organism has been high due to improper use of antibiotics. That made the necessity to develop new drug molecules. In this study an effort was made to find a new alternative. A wild type microorganism was isolated from soil and was identified as Bacillus and confirmed as Bacillus subtilis species by 16S r RNA sequencing. The strain was identified to have the ability to produce bacteriocin by stab overlay assay. Bacteriocin was produced in nutrient broth and that was extracted by organic solvent extraction using chloroform and further purification was carried out by HPLC and the molecular weight of the bacteriocin was analysed by SDSPAGE. Antimicrobial activity was analysed on four strains Pseudomonas sp, Staphylococcus sp, Klebsiella sp and Proteus sp. and was found to be sensitive towards the analyzed strains.

  19. 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

  20. 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

  1. 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

  2. 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...

  3. Using the overlay assay to qualitatively measure bacterial production of and sensitivity to pneumococcal bacteriocins.

    Science.gov (United States)

    Maricic, Natalie; Dawid, Suzanne

    2014-09-30

    Streptococcus pneumoniae colonizes the highly diverse polymicrobial community of the nasopharynx where it must compete with resident organisms. We have shown that bacterially produced antimicrobial peptides (bacteriocins) dictate the outcome of these competitive interactions. All fully-sequenced pneumococcal strains harbor a bacteriocin-like peptide (blp) locus. The blp locus encodes for a range of diverse bacteriocins and all of the highly conserved components needed for their regulation, processing, and secretion. The diversity of the bacteriocins found in the bacteriocin immunity region (BIR) of the locus is a major contributor of pneumococcal competition. Along with the bacteriocins, immunity genes are found in the BIR and are needed to protect the producer cell from the effects of its own bacteriocin. The overlay assay is a quick method for examining a large number of strains for competitive interactions mediated by bacteriocins. The overlay assay also allows for the characterization of bacteriocin-specific immunity, and detection of secreted quorum sensing peptides. The assay is performed by pre-inoculating an agar plate with a strain to be tested for bacteriocin production followed by application of a soft agar overlay containing a strain to be tested for bacteriocin sensitivity. A zone of clearance surrounding the stab indicates that the overlay strain is sensitive to the bacteriocins produced by the pre-inoculated strain. If no zone of clearance is observed, either the overlay strain is immune to the bacteriocins being produced or the pre-inoculated strain does not produce bacteriocins. To determine if the blp locus is functional in a given strain, the overlay assay can be adapted to evaluate for peptide pheromone secretion by the pre-inoculated strain. In this case, a series of four lacZ-reporter strains with different pheromone specificity are used in the overlay.

  4. 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...

  5. Bacteriocins of lactic acid bacteria : extending the family

    NARCIS (Netherlands)

    Alvarez-Sieiro, Patricia; Montalbán-López, Manuel; Mu, Dongdong; Kuipers, Oscar P

    2016-01-01

    Lactic acid bacteria (LAB) constitute a heterogeneous group of microorganisms that produce lactic acid as the major product during the fermentation process. LAB are Gram-positive bacteria with great biotechnological potential in the food industry. They can produce bacteriocins, which are proteinaceo

  6. Bacteriocins from lactic acid bacteria: production, purification, and food applications.

    Science.gov (United States)

    De Vuyst, Luc; Leroy, Frédéric

    2007-01-01

    In fermented foods, lactic acid bacteria (LAB) display numerous antimicrobial activities. This is mainly due to the production of organic acids, but also of other compounds, such as bacteriocins and antifungal peptides. Several bacteriocins with industrial potential have been purified and characterized. The kinetics of bacteriocin production by LAB in relation to process factors have been studied in detail through mathematical modeling and positive predictive microbiology. Application of bacteriocin-producing starter cultures in sourdough (to increase competitiveness), in fermented sausage (anti-listerial effect), and in cheese (anti-listerial and anti-clostridial effects), have been studied during in vitro laboratory fermentations as well as on pilot-scale level. The highly promising results of these studies underline the important role that functional, bacteriocinogenic LAB strains may play in the food industry as starter cultures, co-cultures, or bioprotective cultures, to improve food quality and safety. In addition, antimicrobial production by probiotic LAB might play a role during in vivo interactions occurring in the human gastrointestinal tract, hence contributing to gut health.

  7. 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...

  8. BAGEL2 : mining for bacteriocins in genomic data

    NARCIS (Netherlands)

    de Jong, Anne; van Heel, Auke J.; Kok, Jan; Kuipers, Oscar P.

    2010-01-01

    Mining bacterial genomes for bacteriocins is a challenging task due to the substantial structure and sequence diversity, and generally small sizes, of these antimicrobial peptides. Major progress in the research of antimicrobial peptides and the ever-increasing quantities of genomic data, varying fr

  9. The Circular Bacteriocins Gassericin A and Circularin A

    NARCIS (Netherlands)

    Kawai, Yasushi; Kemperman, Rober; Kok, Jan; Saito, Tadao

    2004-01-01

    Gassericin A, a bacteriocin produced by Lactobacillus gasseri LA39, shows antibacterial activity against a number of Gram-positive food-borne pathogenic bacteria. Circularin A produced by Clostridium beijerinckii ATCC25752 is active against C. tyrobutyricum, a known cheese-spoilage bacterium. Both b

  10. 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.

  11. BAGEL: a web-based bacteriocin genome mining tool

    NARCIS (Netherlands)

    de Jong, A; van Hijum, S.A F T; Bijlsma, Jetta; Kok, J.; Kuipers, O.P.

    2006-01-01

    A common problem in the annotation of open reading frames (ORFs) is the identification of genes that are functionally similar but have limited or no sequence homology. This is particularly the case for bacteriocins, a very diverse group of antimicrobial peptides produced by bacteria and usually enco

  12. 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...

  13. Organization and Nucleotide Sequences of Two Lactococcal Bacteriocin Operons

    NARCIS (Netherlands)

    Belkum, Marco J. van; Hayema, Bert Jan; Jeeninga, Rienk E.; Kok, Jan; Venema, Gerard

    1991-01-01

    Two distinct regions of the Lactococcus lactis subsp. cremoris 9B4 plasmid p9B4-6, each of which specified bacteriocin production as well as immunity, have been sequenced and analyzed by deletion and frameshift mutation analyses. On a 1.8-kb ScaI-ClaI fragment specifying low antagonistic activity, t

  14. Alternatives to antibiotics: bacteriocins, antimicrobial peptides and bacteriophages.

    Science.gov (United States)

    Joerger, R D

    2003-04-01

    Bacteriocins, antimicrobial peptides, and bacteriophage have attracted attention as potential substitutes for, or as additions to, currently used antimicrobial compounds. This publication will review research on the potential application of these alternative antimicrobial agents to poultry production and processing. Bacteriocins are proteinaceous compounds of bacterial origin that are lethal to bacteria other than the producing strain. It is assumed that some of the bacteria in the intestinal tract produce bacteriocins as a means to achieve a competitive advantage, and bacteriocin-producing bacteria might be a desirable part of competitive exclusion preparations. Purified or partially purified bacteriocins could be used as preservatives or for the reduction or elimination of certain pathogens. Currently only nisin, produced by certain strains of Lactococcus lactis subsp. lactis, has regulatory approval for use in certain foods, and its use for poultry products has been studied extensively. Exploration of the application of antimicrobial peptides from sources other than bacteria to poultry has not yet commenced to a significant extent. Evidence for the ability of chickens to produce such antimicrobial peptides has been provided, and it is likely that these peptides play an important role in the defense against various pathogens. Bacteriophages have received renewed attention as possible agents against infecting bacteria. Evidence from several trials indicates that phage therapy can be effective under certain circumstances. Numerous obstacles for the use of phage as antimicrobials for poultry or poultry products remain. Chiefly among them are the narrow host range of many phages, the issue of phage resistance, and the possibility of phage-mediated transfer of genetic material to bacterial hosts. Regulatory issues and the high cost of producing such alternative antimicrobial agents are also factors that might prevent application of these agents in the near future

  15. 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.

  16. Demonstration of bacteriocin activity in bovine and bison strains of Pasteurella multocida. [UV radiation

    Energy Technology Data Exchange (ETDEWEB)

    Chengappa, M.M.; Carter, G.R.

    1977-08-01

    Of 33 strains of Pasteurella multocida examined, 14 showed bacteriocin activity and 17 were susceptible to bacteriocin. The activity was increased by about twofold if the cultures were induced with ultraviolet radiation; however, no increase in bacteriocin activity was observed if the potential producer strains were induced with mitomycin C. The bacteriocin activity of potential producer strains was increased if CaCl/sub 2/ was incorporated in the medium. The patterns of bacteriocin susceptibility indicate that these substances may ultimately contribute to a typing scheme for the species. An extra-chromosomal genetic element was not detected when a potential producer strain was not detected when a potential producer strain was tested by the dye-buoyant density gradient method. This fact suggests that the genetic material responsible for bacteriocin activity in P multocida is located on the host chromosome proper.

  17. 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.

  18. 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...

  19. 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,...

  20. Native and heterologous production of bacteriocins from gram-positive microorganisms.

    Science.gov (United States)

    Muñoz, Mabel; Jaramillo, Diana; Melendez, Adelina Del Pilar; J Alméciga-Diaz, Carlos; Sánchez, Oscar F

    2011-12-01

    In nature, microorganisms can present several mechanisms for setting intercommunication and defense. One of these mechanisms is related to the production of bacteriocins, which are peptides with antimicrobial activity. Bacteriocins can be found in Gram-positive and Gram-negative bacteria. Nevertheless, bacteriocins produced by Gram-positive bacteria are of particular interest due to the industrial use of several strains that belong to this group, especially lactic acid bacteria (LAB), which have the status of generally recognized as safe (GRAS) microorganisms. In this work, we will review recent tendencies in the field of invention and state of art related to bacteriocin production by Gram-positive microorganism. Hundred-eight patents related to Gram-positive bacteriocin producers have been disclosed since 1965, from which 57% are related bacteriocins derived from Lactococcus, Lactobacillus, Streptococcus, and Pediococcus strains. Surprisingly, patents regarding heterologous bacteriocins production were mainly presented just in the last decade. Although the major application of bacteriocins is concerned to food industry to control spoilage and foodborne bacteria, during the last years bacteriocin applications have been displacing to the diagnosis and treatment of cancer, and plant disease resistance and growth promotion.

  1. 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.

  2. 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.

  3. 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

  4. 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 ...

  5. 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

  6. 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.

  7. Isolation and partial characterization of bacteriocins from Pediococcus species.

    Science.gov (United States)

    Jamuna, M; Jeevaratnam, K

    2004-09-01

    Lactic acid bacteria have received increased attention as a potential food preservative due to their strong antagonistic activity against many food-spoilage and pathogenic organisms. Three Pediococcus species, P. acidilactici NCIM 2292 , P. pentosaceous. NCIM 2296 and P. cervisiae NCIM 2171, were evaluated for bacteriocin production. Inhibitory substance were produced during the late growth phase and maximum production occurred at 37 degrees after 36-48 h of incubation. Bacteriocins partially purified from these species by cold-acetone precipitation at 0 degrees C and cell adsorption desorption techniques have a broad inhibitory spectrum against microorganisms, including gram-negative bacteria such as Escherichia coli and Pseudomonas. Proteolytic enzymes inactivated these peptides, but amylase and lipase did not show any effect. The bacteriocins were stable over a wide pH range (3-8) and apparently most active at pH 4.0-5.0. They were heat-stable (1 h at approximately 80 degrees C and autoclaving) at pH 5.0. No loss in activity was observed when stored under refrigeration (4-8 degrees C). Tris-Tricine SDS-PAGE revealed the molecular masses of these peptides to be between 3.5 and 5.0 kDa.

  8. Improved adsorption-desorption extraction applied to the partial characterization of the antilisterial bacteriocin produced by Carnobacterium maltaromaticum C2

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    F. L Tulini

    2010-06-01

    Full Text Available Bacteriocins are ribosomally produced peptides useful for food biopreservation. An improved adsorption-desorption process is proposed for the partial purification of the bacteriocin produced by the fish isolate Carnobacterium maltaromaticum C2. Analyzis of extract by SDS-PAGE indicated this method may offer an alternative to improve the yield of purification of bacteriocins.

  9. Examination of Lactic Acid Bacteria to Secretion of Bacteriocins

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    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

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

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    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.

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

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    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.

  12. 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

  13. 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...

  14. Characterisation of an antiviral pediocin-like bacteriocin produced by Enterococcus faecium.

    Science.gov (United States)

    Todorov, Svetoslav Dimitrov; Wachsman, Monica; Tomé, Elisabetta; Dousset, Xavier; Destro, Maria Teresa; Dicks, Leon Milner Theodore; Franco, Bernadette Dora Gombossy de Melo; Vaz-Velho, Manuella; Drider, Djamel

    2010-10-01

    The bacteriocin-producing strain Enterococcus faecium ST5Ha was isolated from smoked salmon and identified by biomolecular techniques. Ent. faecium ST5Ha produces a pediocin-like bacteriocin with activity against several lactic acid bacteria, Listeria spp. and some other human and food pathogens, and remarkably against HSV-1 virus. Bacteriocin ST5Ha was produced at high levels in MRS broth at 30 degrees C and 37 degrees C, reaching a maximum production of 1.0 x 10(9) AU/ml, checked against Listeria ivanovii ATCC19119 as target strain and surrogate of pathogenic strain Listeria monocytogenes. The molecular weight of bacteriocin ST5Ha was estimated to be 4.5 kDa according to tricine-SDS-PAGE data. Ent. faecium ST5Ha harbors a 1.044 kb chromosomal DNA fragment fitting in size to that of pediocin PA-1/AcH. In addition, the sequencing of bacteriocin ST5Ha gene indicated 99% of DNA homology to pediocin PA-1/AcH. The combined application of low levels (below MIC) of ciprofloxacin and bacteriocin ST5Ha resulted in a synergetic effect in the inhibition of target strain L. ivanovii ATCC19119. Bacteriocin ST5Ha displayed antiviral activity against HSV-1, an important human pathogen, with a selectivity index of 173. To the best of our knowledge, this is the first report on Ent. faecium as a potential producer of pediocin-like bacteriocin with antiviral activity.

  15. Identification, purification and characterization of laterosporulin, a novel bacteriocin produced by Brevibacillus sp. strain GI-9.

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    Pradip Kumar Singh

    Full Text Available BACKGROUND: Bacteriocins are antimicrobial peptides that are produced by bacteria as a defense mechanism in complex environments. Identification and characterization of novel bacteriocins in novel strains of bacteria is one of the important fields in bacteriology. METHODOLOGY/FINDINGS: The strain GI-9 was identified as Brevibacillus sp. by 16 S rRNA gene sequence analysis. The bacteriocin produced by strain GI-9, namely, laterosporulin was purified from supernatant of the culture grown under optimal conditions using hydrophobic interaction chromatography and reverse-phase HPLC. The bacteriocin was active against a wide range of Gram-positive and Gram-negative bacteria. MALDI-TOF experiments determined the precise molecular mass of the peptide to be of 5.6 kDa and N-terminal sequencing of the thermo-stable peptide revealed low similarity with existing antimicrobial peptides. The putative open reading frame (ORF encoding laterosporulin and its surrounding genomic region was fished out from the draft genome sequence of GI-9. Sequence analysis of the putative bacteriocin gene did not show significant similarity to any reported bacteriocin producing genes in database. CONCLUSIONS: We have identified a bacteriocin producing strain GI-9, belonging to the genus Brevibacillus sp. Biochemical and genomic characterization of laterosporulin suggests it as a novel bacteriocin with broad spectrum antibacterial activity.

  16. Sec-mediated secretion of bacteriocin enterocin P by Lactococcus lactis

    NARCIS (Netherlands)

    Herranz, C; Driessen, AJM

    2005-01-01

    Most lactic acid bacterium bacteriocins utilize specific leader peptides and dedicated machineries for secretion. In contrast, the enterococcal bacteriocin enterocin P (EntP) contains a typical signal peptide that directs its secretion when heterologously expressed in Lactococcus lactis. Signal pept

  17. 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.

  18. Structure of the atypical bacteriocin pectocin M2 implies a novel mechanism of protein uptake.

    Science.gov (United States)

    Grinter, Rhys; Josts, Inokentijs; Zeth, Kornelius; Roszak, Aleksander W; McCaughey, Laura C; Cogdell, Richard J; Milner, Joel J; Kelly, Sharon M; Byron, Olwyn; Walker, Daniel

    2014-07-01

    The colicin-like bacteriocins are potent protein antibiotics that have evolved to efficiently cross the outer membrane of Gram-negative bacteria by parasitizing nutrient uptake systems. We have structurally characterized the colicin M-like bacteriocin, pectocin M2, which is active against strains of Pectobacterium spp. This unusual bacteriocin lacks the intrinsically unstructured translocation domain that usually mediates translocation of these bacteriocins across the outer membrane, containing only a single globular ferredoxin domain connected to its cytotoxic domain by a flexible α-helix, which allows it to adopt two distinct conformations in solution. The ferredoxin domain of pectocin M2 is homologous to plant ferredoxins and allows pectocin M2 to parasitize a system utilized by Pectobacterium to obtain iron during infection of plants. Furthermore, we identify a novel ferredoxin-containing bacteriocin pectocin P, which possesses a cytotoxic domain homologous to lysozyme, illustrating that the ferredoxin domain acts as a generic delivery module for cytotoxic domains in Pectobacterium.

  19. 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

  20. Bacteriocins - exploring alternatives to antibiotics in mastitis treatment.

    Science.gov (United States)

    Pieterse, Reneé; Todorov, Svetoslav D

    2010-07-01

    Mastitis is considered to be the most costly disease affecting the dairy industry. Management strategies involve the extensive use of antibiotics to treat and prevent this disease. Prophylactic dosages of antibiotics used in mastitis control programmes could select for strains with resistance to antibiotics. In addition, a strong drive towards reducing antibiotic residues in animal food products has lead to research in finding alternative antimicrobial agents. In this review we have focus on the pathogenesis of the mastitis in dairy cows, existing antibiotic treatments and possible alternative for application of bacteriocins from lactic acid bacteria in the treatment and prevention of this disease.

  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

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    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. Nisin and class IIa bacteriocin resistance among Listeria and other foodborne pathogens and spoilage bacteria.

    Science.gov (United States)

    Kaur, Gurpreet; Malik, Ravinder Kumar; Mishra, Santosh Kumar; Singh, Tejinder Pal; Bhardwaj, Arun; Singroha, Garima; Vij, Shilpa; Kumar, Naresh

    2011-06-01

    Food safety has been an important issue globally due to increasing foodborne diseases and change in food habits. To inactivate foodborne pathogens, various novel technologies such as biopreservation systems have been studied. Bacteriocins are ribosomally synthesized peptides or proteins with antimicrobial activity produced by different groups of bacteria, but the bacteriocins produced by many lactic acid bacteria offer potential applications in food preservation. The use of bacteriocins in the food industry can help reduce the addition of chemical preservatives as well as the intensity of heat treatments, resulting in foods that are more naturally preserved. However, the development of highly tolerant and/or resistant strains may decrease the efficiency of bacteriocins as biopreservatives. Several mechanisms of bacteriocin resistance development have been proposed among various foodborne pathogens. The acquiring of resistance to bacteriocins can significantly affect physiological activity profile of bacteria, alter cell-envelope lipid composition, and also modify the antibiotic susceptibility/resistance profile of bacteria. This article presents a brief review on the scientific research about the various possible mechanisms involved in the development of resistance to nisin and Class IIa bacteriocins among the foodborne pathogens.

  4. Bacteriocin activity against various pathogens produced by Pediococcus pentosaceus VJ13 isolated from Idly batter.

    Science.gov (United States)

    Vidhyasagar, Venkatasubramanian; Jeevaratnam, Kadirvelu

    2013-11-01

    Bacteriocins, an antimicrobial peptide, is known to have wide spectrum antimicrobial activity against various pathogens. Because they are easily digested in the intestine, they are considered as safe and are widely used as food preservatives. Hence their purification and characterization have attracted considerable attraction, especially for those having activity against human pathogens. In this study, the bacteriocin produced by Pediococcus pentosaceus VJ13 was precipitated with cold acetone and purified by gel permeation chromatography and hydrophobic interaction chromatography. The bacteriocin exhibited antimicrobial activity against various pathogens, like Mycobacterium smegmatis, Klebsiella pneumonia, Clostridium perfringens and Staphylococcus epidermidis. The activity of bacteriocin was lost completely after treatment with protease, which revealed its proteinaceous nature. The bacteriocin was stable up to 100°C and exhibited antilisterial property which is a characteristic feature of class IIa bacteriocins. It was active within the pH range of 2-8 and stable against various chemicals and denaturants. Tricine SDS-PAGE revealed its molecular weight to be 4.0 kDa, where the corresponding activity against Listeria monocytogenes was also noted. Treatment of L. monocytogenes with bacteriocin decreased the viable cell count, and scanning electron microscope analysis revealed membrane pore formation that resulted in the release of intracellular content, suggesting its bactericidal effect.

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

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    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.

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

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    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.

  7. Encapsulation of Lactobacillus plantarum 423 and its Bacteriocin in Nanofibers.

    Science.gov (United States)

    Heunis, T D J; Botes, M; Dicks, L M T

    2010-03-01

    Plantaricin 423, produced by Lactobacillus plantarum 423, was encapsulated in nanofibers that were produced by the electrospinning of 18% (w/v) polyethylene oxide (200 000 Da). The average diameter of the nanofibers was 288 nm. Plantaricin 423 activity decreased from 51 200 AU/ml to 25 600 AU/ml and from 204 800 AU/ml to 51 200 AU/ml after electrospinning, as determined against Lactobacillus sakei DSM 20017 and Enterococcus faecium HKLHS, respectively. Cells of L. plantarum 423 encapsulated in nanofibers decreased from 2.3 × 10(10) cfu/ml before electrospinning to 4.7 × 10(8) cfu/ml thereafter. Cells entrapped in the nanofibers continued to produce plantaricin 423. This is the first report on the encapsulation of a bacteriocin and cells of L. plantarum in nanofibers. The method may be used to design a drug delivery system for bacteriocins and the encapsulation of probiotic lactic acid bacteria. The technology is currently being optimized.

  8. 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

  9. Importance in dairy technology of bacteriocins produced by dairy starter cultures

    Directory of Open Access Journals (Sweden)

    Bedia Şimşek

    2002-03-01

    Full Text Available Bacteriocins produced by Lactic acid bacteria (LAB and propionic acid bacteria (PAB are heterogeneous group of peptide inhibitors which include lantibiotics (class I, e. g. nisin, small heat-stable peptides (class II, e. g. pediocin PA-1 and large heat-labile proteins (class III, e. g. helveticin J. Many bacteriocins belonging to the first two groups can be successfully used to inhibit undesirable microorganisms in foods, but only nisin is produced industrially and is used as a food preservative. LAB and PAB develops easily in milk and milk products. LAB and PAB growth in dairy products can cause microbial interference to spoilage and pathogenic bacteria through several metabolits, specially bacteriocins. The review deals with the description of milk-borne bacteriocins and their application in milk and milk products either to extend the shelf life or to inhibit milk pathogens.

  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.

  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. 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.

  13. 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

    2016-04-13

    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

  14. 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.

  15. 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

  16. 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 ...

  17. Bacteriocin-Producing Lactic Acid Bacteria Isolated from Traditional Fermented Food

    OpenAIRE

    Kormin, Salasiah; Rusul, Gulam; Radu, Son; Ling, Foo Hooi

    2001-01-01

    Lactic Acid Bacteria (LAB) isolated from several traditional fermented foods such as “tempeh”, “tempoyak” and “tapai” were screened for the production of bacteriocin. One strain isolated from “tempeh” gives an inhibitory activity against several LAB. The strain was later identified as Lactobacillus plantarum BS2. Study shows that the inhibitory activity was not caused by hydrogen peroxide, organic acids or bacteriophage. The bacteriocin production was maximum after 10 hours of incubation with...

  18. 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.

  19. 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.

  20. 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.

  1. 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

  2. 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

  3. The study of effect bacteriocin producing Lactoco ccus lactis on Listeria monocytogenes and Bacillus cereus

    Directory of Open Access Journals (Sweden)

    M. Mirhossieni, M.Sc

    2007-01-01

    Full Text Available AbstractBackground and purpose: Dairy products often associated with problems such as short shelf life and poor hygiene control. A novel approach is to utilize bacteriocin or bacteriocin producer strains, to control undesirable micro flora as Listeria monocytogenes and Bacillus cereus in foods. Hence, we studied the effect of nisin like producing Lactococcus lactis against Listeria monocytogenes and Bacillus cereus, in order to compare the isolated strain within different countries.Materials and Methods: In this research we studied the effect of nisin like producing Lactococcus lactis, with producer spot test method. We also used supernatant from 24 h culture of Lactoccus lactis. Moreover, we studied the effect of bacteriocin on Listeria monocytogenes and Bacillus cereus growth curves.Results: The growth of both strains was inhibited by the bacteriocin. Conclusion: According to our results, the bacteriocin could be used in liquid food with bacteriocin added directly or as a starter culture in fermentation. This would inhibit the growth of Listeria monocytogenes; furthermore, Bacillus cereus is used to reduce food poisoning for fermented food products.

  4. 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.

  5. 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.

  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. 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.

  8. 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

  9. 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

  10. 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.

  11. Characterization of a bacteriocin produced by Enterococcus faecalis N1-33 and its application as a food preservative.

    Science.gov (United States)

    Hata, Tomomi; Alemu, Melaku; Kobayashi, Miho; Suzuki, Chise; Nitisinprasert, Sunee; Ohmomo, Sadahiro

    2009-03-01

    A bacteriocin-producing strain, N1-33, isolated from fermented bamboo shoot was identified as Enterococcus faecalis. The pH-adjusted culture supernatant of this strain consisted of several peptides with bacteriocin activity, and the supernatant inhibited the growth of pathogenic bacteria such as Listeria monocytogenes. The major peptide with bacteriocin activity was purified, and the first 39 amino acid residues of the bacteriocin were found to be identical to enterocin MR10A produced by E. faecalis MRR10-3. Addition of the pH-adjusted and concentrated culture supernatant of strain N1-33 caused a marked reduction in the growth of Bacillus cereus in custard cream and L. monocytogenes in pickled cucumber. These results suggest the potential use of the bacteriocin produced by strain N1-33 in food biopreservation.

  12. 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.

  13. 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.

  14. 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.

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

    Science.gov (United States)

    Malheiros, Patrícia S.; Sant’Anna, Voltaire; Todorov, Svetoslav D.; Franco, Bernadette D.G.M.

    2015-01-01

    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 (R 2 = 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. PMID:26413066

  16. 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.

  17. The Potential of Class II Bacteriocins to Modify Gut Microbiota to Improve Host Health

    Science.gov (United States)

    Umu, Özgün C. O.; Bäuerl, Christine; Oostindjer, Marije; Pope, Phillip B.; Hernández, Pablo E.; Pérez-Martínez, Gaspar; Diep, Dzung B.

    2016-01-01

    Production of bacteriocins is a potential probiotic feature of many lactic acid bacteria (LAB) as it can help prevent the growth of pathogens in gut environments. However, knowledge on bacteriocin producers in situ and their function in the gut of healthy animals is still limited. In this study, we investigated five bacteriocin-producing strains of LAB and their isogenic non-producing mutants for probiotic values. The LAB bacteriocins, sakacin A (SakA), pediocin PA-1 (PedPA-1), enterocins P, Q and L50 (enterocins), plantaricins EF and JK (plantaricins) and garvicin ML (GarML), are all class II bacteriocins, but they differ greatly from each other in terms of inhibition spectrum and physicochemical properties. The strains were supplemented to mice through drinking water and changes on the gut microbiota composition were interpreted using 16S rRNA gene analysis. In general, we observed that overall structure of the gut microbiota remained largely unaffected by the treatments. However, at lower taxonomic levels, some transient but advantageous changes were observed. Some potentially problematic bacteria were inhibited (e.g., Staphylococcus by enterocins, Enterococcaceae by GarML, and Clostridium by plantaricins) and the proportion of LAB was increased in the presence of SakA-, plantaricins- and GarML-producing bacteria. Moreover, the treatment with GarML-producing bacteria co-occurred with decreased triglyceride levels in the host mice. Taken together, our results indicate that several of these bacteriocin producers have potential probiotic properties at diverse levels as they promote favorable changes in the host without major disturbance in gut microbiota, which is important for normal gut functioning. PMID:27695121

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

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    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

  19. 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

  20. 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

  1. 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

  2. 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.

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

    Directory of Open Access Journals (Sweden)

    I.I. Arief

    2014-10-01

    Full Text Available One purpose of food preservation is to extend the shelf life of foods. Biological preservations canbe conducted by adding antimicrobial substances, such as bacteriocin produced by lactic acid bacteriaand has been characterized as biopreservatives. The aims of this research were to evaluate antimicrobialactivity of bacteriocin produced by indigenous lactic acid bacteria Lactobacillus plantarum 2C12isolated from local beef and to study the quality of beef meatball with 0.3% bacteriocin asbiopreservative 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 2C12could inhibit pathogenic bacteria such as Escherichia coli, Staphylococcus aureus and SalmonellaTyphimurium. Bacteriocin was effective as well as nitrite as biopreservatives of meatballs by inhibitingthe growth of total microbes and E. coli. The addition of bacteriocin did not lead the physical andnutritional changes in the meatballs. The quality of meatball with bacteriocin treatment conformed withIndonesia National Standard of meatball.

  4. 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.

  5. The partial characterization of the antibacterial peptide bacteriocin G2 produced by the probiotic bacteria Lactobacillus plantarum G2

    Directory of Open Access Journals (Sweden)

    SVETLANA L. ŠEATOVIĆ

    2011-05-01

    Full Text Available The aim of this study was the partial characterization of the antimicrobial peptide bacteriocin G2 produced by probiotic bacteria Lactobacillus plantarum G2, which was isolated from a clinical sample of a healthy person. Antimicrobial substance was secreted in the supernatant of an L. plantarum G2 culture, and showed a diverse spectrum of antimicrobial activity of all the tested strains of the genera Lactobacillus and the pathogenic bacteria Staphylococcus aureus and Salmonella аbony. Isoelectric focusing revealed that bacteriocin G2 is a cationic peptide (pI about 10 with a molecular mass of 2.2 kDa according to tricine–sodium dodecyl sulphate–polyacrylamide gel electrophoresis, SDS-PAGE. The antimicrobial activity of bacteriocin G2 was diminished by the proteolytic action of trypsin and proteinase K. Bacteriocin G2 preserved its biological activity in the temperature range 40–60 °C (15 min, which was lost at 80 °C. Bacteriocin G2 was stable in the pH range 2–9, while treatment with 1 % Tween 80 and 1 % urea resulted in increased antimicrobial activity. The probiotic strain L. plantarum G2 produces the antimicrobial substance proteinaceous in nature with bacteriocin characteristics. Bacteriocin production is one of the key properties of probiotic bacteria with clinical potential as anti-infective agents, which will increase the likelihood of its in vivo efficacy.

  6. Physical chemical and biological characterization of a new bacteriocin produced byBacillus cereusNS02

    Institute of Scientific and Technical Information of China (English)

    Senbagam D; Gurusamy R; Senthilkumar B

    2013-01-01

    Objective:To screen the bacteriocinogenic isolate from buffalo milk and to characterize it on physical, chemical and biological aspects for the application in biopreservation.Methods:Bacillus cereus(B. cereus) was isolated and assessed for its baceteriocinogenic activity. Bacteriocin was produced and purified by ammonium sulphate precipitation, dialysis and gel filtration chromatography.Purified bacteriocin was used to check its antimicrobial activity against food borne bacteria.Effect and stability of bacteriocin was determined with the respect to temperature, pH, enzymes, organic solvents and chemicals.Bacteriocin was also subjected toSDSPAGE analysis to determine its molecular weight.In addition, functional groups exist in the bacteriocin was determined byFTIR analysis.Results:B. cereus was identified by16S rRNA sequence analysis.Bacteriocin showed increased activity against all the bacteria used and its activity unit was found to be51,200AU/mL.It was stable to high temperature(100 ℃) and wide range of pH(3-10), sensitive to proteolytic enzymes and resistant to nonproteolytic enzymes.It was low molecular weight(3.5 -6KDa) protein andFTIR study revealed the presence of amide group andNH stretching.Conclusions:Bacteriocin produced in this study possesses the highest antimicrobial activity against both gram positive and gram negative bacteria thereby it has immense application as biopreservative agent.FTIR proved its peptide nature.

  7. 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

  8. Identification and characterization of two novel clostridial bacteriocins, circularin A and closticin 574

    NARCIS (Netherlands)

    Kemperman, R; Kuipers, A; Karsens, H; Nauta, A; Kuipers, O; Kok, J

    2003-01-01

    Two novel antibacterial peptides of clostridiall species were purified, N-terminally sequenced, and characterized. Moreover, their structural genes were identified. Closticin 574 is an 82-amino-acid bacteriocin produced by Clostridium tyrobutyricum ADRIAT 932. The supernatant of the producing strain

  9. Novel mechanism of bacteriocin secretion and immunity carried out by lactococcal multidrug resistance proteins

    NARCIS (Netherlands)

    Gajic, O; Buist, G; Kojic, M; Topisirovic, L; Kuipers, OP; Kok, J

    2003-01-01

    A natural isolate of Lactococcus lactis was shown to produce two narrow spectrum class II bacteriocins, designated LsbA and LsbB. The cognate genes are located on a 5.6-kb plasmid within a gene cluster specifying LmrB, an ATP-binding cassette-type multidrug resistance transporter protein. LsbA is a

  10. 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...

  11. 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.

  12. Purification and characterisation of acidocin D20079, a bacteriocin produced by Lactobacillus acidophilus DSM 20079.

    Science.gov (United States)

    Deraz, Sahar F; Karlsson, Eva Nordberg; Hedström, Martin; Andersson, Maria M; Mattiasson, Bo

    2005-06-29

    Bacteriocins are natural antimicrobial agents produced by food fermentative bacteria. Lactobacillus acidophilus DSM 20079 produces a small bacteriocin, with a molecular mass of 6.6 kDa, designated acidocin D20079. This antimicrobial peptide was extremely heat-stable (30 min at 121 degrees C) and was active over a wide pH range. It was found to be sensitive to proteolytic enzymes (trypsin, ficin, pepsin, papain, and proteinase K). Acidocin D20079 has a narrow inhibitory spectrum restricted to the genus Lactobacillus which includes L. sakei NCDO 2714, an organism known to cause anaerobic spoilage of vacuum-packaged meat. Maximum production of acidocin D20079 in MRS broth was detected at pH 6.0, and the peptide was purified by ammonium sulphate precipitation followed by sequential cation exchange and hydrophobic interaction chromatography. Purified acidocin D20079 spontaneously formed spherulite crystals during dialysis. As the N-terminus was found to be blocked for sequencing, matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry was used to determine a partial sequence, and the molecular mass of the bacteriocin in the formed crystals (6.6 kDa). Estimates of the molecular weight of the partially purified peptide, using tricine-SDS-PAGE, in which bacteriocin activity was confirmed by overlayer techniques were in accordance with this value. PMID:15925717

  13. Bacteriocins and other bioactive substances of probiotic lactobacilli as biological weapons against Neisseria gonorrhoeae.

    Science.gov (United States)

    Ruíz, Francisco O; Pascual, Liliana; Giordano, Walter; Barberis, Lucila

    2015-04-01

    In the search of new antimicrobial agents against Neisseria gonorrhoeae, the bacteriocins-producing probiotic lactobacilli deserve special attention. The inhibitory effects of biosubstances such as organic acids, hydrogen peroxide and each bacteriocin-like inhibitory substance (BLIS) L23 and L60 on the growth of different gonococcal strains were investigated. Different non-treated and treated cell-free supernatants of two probiotic lactobacilli containing these metabolites were used. The aims of this work were (i) to evaluate the antimicrobial activity of the biosubstances produced by two probiotic lactobacilli, estimating the proportion in which each of them is responsible for the inhibitory effect, (ii) to define their minimum inhibitory concentrations (MICs) and, (iii) to determine the potential interactions between these biosubstances against N. gonorrhoeae. The main antimicrobial metabolites were the BLIS-es L23 and L60 in comparison with other biosubstances. Proportionally, their contributions to the inhibition on the gonococcal growth were 87.28% and 80.66%, respectively. The MIC values of bacteriocins were promising since these substances, when diluted, showed considerable inhibitory activity for all gonococci. In the interaction between bacteriocins, 100% of synergism was found on the gonococcal growth. In summary, this study indicates that both L23 and L60 could potentially serve to design new bioproducts against N. gonorrhoeae.

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

    DEFF Research Database (Denmark)

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

    2012-01-01

    that the 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...

  15. Complementary and Overlapping Selectivity of the Two-Peptide Bacteriocins Plantaricin EF and JK

    NARCIS (Netherlands)

    Moll, Gert N.; Akker, Emile van den; Hauge, Håvard H.; Nissen-Meyer, Jon; Nes, Ingolf F.; Konings, Wil N.; Driessen, Arnold J.M.

    1999-01-01

    Plantaricin EF and JK are both two-peptide bacteriocins produced by Lactobacillus plantarum C11. The mechanism of plantaricin EF and JK action was studied on L. plantarum 965 cells. Both plantaricins form pores in the membranes of target cells and dissipate the transmembrane electrical potential (Δψ

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

    Directory of Open Access Journals (Sweden)

    Baby Joseph

    2013-12-01

    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.

  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. Genome mining demonstrates the widespread occurrence of gene clusters encoding bacteriocins in cyanobacteria.

    Directory of Open Access Journals (Sweden)

    Hao Wang

    Full Text Available Cyanobacteria are a rich source of natural products with interesting biological activities. Many of these are peptides and the end products of a non-ribosomal pathway. However, several cyanobacterial peptide classes were recently shown to be produced through the proteolytic cleavage and post-translational modification of short precursor peptides. A new class of bacteriocins produced through the proteolytic cleavage and heterocyclization of precursor proteins was recently identified from marine cyanobacteria. Here we show the widespread occurrence of bacteriocin gene clusters in cyanobacteria through comparative analysis of 58 cyanobacterial genomes. A total of 145 bacteriocin gene clusters were discovered through genome mining. These clusters encoded 290 putative bacteriocin precursors. They ranged in length from 28 to 164 amino acids with very little sequence conservation of the core peptide. The gene clusters could be classified into seven groups according to their gene organization and domain composition. This classification is supported by phylogenetic analysis, which further indicated independent evolutionary trajectories of gene clusters in different groups. Our data suggests that cyanobacteria are a prolific source of low-molecular weight post-translationally modified peptides.

  20. Strategies for the use of bacteriocins in Gram-negative bacteria: relevance in food microbiology.

    Science.gov (United States)

    Prudêncio, Cláudia Vieira; Dos Santos, Miriam Teresinha; Vanetti, Maria Cristina Dantas

    2015-09-01

    Bacteriocins are ribosomally synthesized peptides that have bacteriostatic or bactericidal effects on other bacteria. The use of bacteriocins has emerged as an important strategy to increase food security and to minimize the incidence of foodborne diseases, due to its minimal impact on the nutritional and sensory properties of food products. Gram-negative bacteria are naturally resistant to the action of bacteriocins produced by Gram-positive bacteria, which are widely explored in foods. However, these microorganisms can be sensitized by mild treatments, such as the use of chelating agents, by treatment with plant essential oils or by physical treatments such as heating, freezing or high pressure processing. This sensitization is important in food microbiology, because most pathogens that cause foodborne diseases are Gram-negative bacteria. However, the effectiveness of these treatments is influenced by several factors, such as pH, temperature, the composition of the food and target microbiota. In this review, we comment on the main methods used for the sensitization of Gram-negative bacteria, especially Salmonella, to improve the action of bacteriocins produced by Gram-positive bacteria.

  1. 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

  2. Partial purification and characterization of bacteriocin produced by Enterococcus faecalis DU10 and its probiotic attributes.

    Science.gov (United States)

    Perumal, Venkatesh; Repally, Ayyanna; Dasari, Ankaiah; Venkatesan, Arul

    2016-10-01

    A novel bacteriocin produced by avian duck isolated lactic acid bacterium Enterococcus faecalis DU10 was isolated. This bacteriocin showed a broad spectrum of antibacterial activity against important food-borne pathogens and was purified by size exclusion chromatography followed by reverse-phase high-performance liquid chromatography in a C-18 column. Tricine-SDS PAGE revealed the presence of a band with an estimated molecular mass of 6.3 kDa. The zymogram clearly linked the antimicrobial activity with this band. This result was further confirmed by mass-assisted laser desorption ionization time-of-flight mass spectrometry, since a sharp peak corresponding to 6.313 kDa was detected and the functional groups were revealed by Fourier transform infrared spectroscopy. Bacteriocin DU10 activity was found sensitive to proteinase-K and pepsin and partially affected by trypsin and α-chymotrypsin. The activity of bacteriocin DU10 was partially resistant to heat treatments ranging from 30 to 90°C for 30 min. It also withstood a treatment at 121°C for 10 min. Cytotoxicity of bacteriocin DU10 by methyl-thiazolyl-diphenyl-tetrazolium bromide assay showed that the viability of HT-29 and HeLa cells decreased 60 ± 0.7% and 43 ± 4.8%, respectively, in the presence of 3,200 AU/mL of bacteriocin. The strain withstood 0.3% w/v of bile oxgall and pH 2 affected the bacterial growth between 2 and 4 hr of incubation. Adhesion properties examined with HT-29 cell line showed 69.85% initial population of strain E. faecalis DU10, which was found to be strongly adhered to this cell line. These results conclude bacteriocin DU10 may be used as a potential biopreservative and E. faecalis DU10 may be used as a potential probiont to control Salmonella infections.

  3. Cloning, purification, and functional characterization of Carocin S2, a ribonuclease bacteriocin produced by Pectobacterium carotovorum

    Directory of Open Access Journals (Sweden)

    Tzeng Kuo-Ching

    2011-05-01

    Full Text Available Abstract Background Most isolates of Pectobacterium carotovorum subsp. carotovorum (Pcc produce bacteriocins. In this study, we have determined that Pcc strain F-rif-18 has a chromosomal gene encoding the low-molecular-weight bacteriocin, Carocin S2, and that this bacteriocin inhibits the growth of a closely related strain. Carocin S2 is inducible by ultraviolet radiation but not by mutagenic agents such as mitomycin C. Results A carocin S2-defective mutant, TF1-2, was obtained by Tn5 insertional mutagenesis using F-rif-18. A 5706-bp DNA fragment was detected by Southern blotting, selected from a genomic DNA library, and cloned to the vector, pMS2KI. Two adjacent complete open reading frames within pMS2KI were sequenced, characterized, and identified as caroS2K and caroS2I, which respectively encode the killing protein and immunity protein. Notably, carocin S2 could be expressed not only in the mutant TF1-2 but also in Escherichia coli DH5α after entry of the plasmid pMS2KI. Furthermore, the C-terminal domain of CaroS2K was homologous to the nuclease domains of colicin D and klebicin D. Moreover, SDS-PAGE analysis showed that the relative mass of CaroS2K was 85 kDa and that of CaroS2I was 10 kDa. Conclusion This study shown that another nuclease type of bacteriocin was found in Pectobacterium carotovorum. This new type of bacteriocin, Carocin S2, has the ribonuclease activity of CaroS2K and the immunity protein activity of CaroS2I.

  4. 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.

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

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    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

  6. 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, ...

  7. 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.

    Science.gov (United States)

    Todorov, Svetoslav D

    2008-01-01

    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.

  8. Characterization of a heat stable anti-listerial bacteriocin produced by vancomycin sensitive Enterococcus faecium isolated from idli batter

    OpenAIRE

    Vijayendra, S.V.N; Rajashree, K.; Halami, Prakash M

    2010-01-01

    Lactic acid bacteria (LAB) are known to produce various types of bacteriocins, ribosomally synthesized polypeptides, which have antibacterial spectrum against many food borne pathogens. Listeria monocytogenes, a pathogenic bacterium, is of particular concern to the food industry because of its ability to grow even at refrigeration temperatures and its tolerance to preservative agents. Some of the bacteriocins of LAB are known to have anti-listerial property. In the present study, the bacterio...

  9. 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)

  10. 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.

  11. Characterization of a heat stable anti-listerial bacteriocin produced by vancomycin sensitive Enterococcus faecium isolated from idli batter.

    Science.gov (United States)

    Vijayendra, S V N; Rajashree, K; Halami, Prakash M

    2010-06-01

    Lactic acid bacteria (LAB) are known to produce various types of bacteriocins, ribosomally synthesized polypeptides, which have antibacterial spectrum against many food borne pathogens. Listeria monocytogenes, a pathogenic bacterium, is of particular concern to the food industry because of its ability to grow even at refrigeration temperatures and its tolerance to preservative agents. Some of the bacteriocins of LAB are known to have anti-listerial property. In the present study, the bacteriocin produced by vancomycin sensitive Enterococcus faecium El and J4 isolated from idli batter samples was characterized. The isolates were found to tolerate high temperatures of 60°C for 15 and 30 min and 70°C for 15 min. The bacteriocin was found to be heat stable and had anti-listerial activity. The bacteriocin did not lost anti-listerial activity when treated at 100°C for 30 min or at 121°C for 15 min. The bacteriocin lost its antimicrobial activity after treating with trypsin, protinase-K, protease and peptidase. PMID:23100837

  12. Characterization of a heat stable anti-listerial bacteriocin produced by vancomycin sensitive Enterococcus faecium isolated from idli batter.

    Science.gov (United States)

    Vijayendra, S V N; Rajashree, K; Halami, Prakash M

    2010-06-01

    Lactic acid bacteria (LAB) are known to produce various types of bacteriocins, ribosomally synthesized polypeptides, which have antibacterial spectrum against many food borne pathogens. Listeria monocytogenes, a pathogenic bacterium, is of particular concern to the food industry because of its ability to grow even at refrigeration temperatures and its tolerance to preservative agents. Some of the bacteriocins of LAB are known to have anti-listerial property. In the present study, the bacteriocin produced by vancomycin sensitive Enterococcus faecium El and J4 isolated from idli batter samples was characterized. The isolates were found to tolerate high temperatures of 60°C for 15 and 30 min and 70°C for 15 min. The bacteriocin was found to be heat stable and had anti-listerial activity. The bacteriocin did not lost anti-listerial activity when treated at 100°C for 30 min or at 121°C for 15 min. The bacteriocin lost its antimicrobial activity after treating with trypsin, protinase-K, protease and peptidase.

  13. 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...

  14. The Crystal Structure of the Lipid II-degrading Bacteriocin Syringacin M Suggests Unexpected Evolutionary Relationships between Colicin M-like Bacteriocins

    Science.gov (United States)

    Grinter, Rhys; Roszak, Aleksander W.; Cogdell, Richard J.; Milner, Joel J.; Walker, Daniel

    2012-01-01

    Colicin-like bacteriocins show potential as next generation antibiotics with clinical and agricultural applications. Key to these potential applications is their high potency and species specificity that enables a single pathogenic species to be targeted with minimal disturbance of the wider microbial community. Here we present the structure and function of the colicin M-like bacteriocin, syringacin M from Pseudomonas syringae pv. tomato DC3000. Syringacin M kills susceptible cells through a highly specific phosphatase activity that targets lipid II, ultimately inhibiting peptidoglycan synthesis. Comparison of the structures of syringacin M and colicin M reveals that, in addition to the expected similarity between the homologous C-terminal catalytic domains, the receptor binding domains of these proteins, which share no discernible sequence homology, share a striking structural similarity. This indicates that the generation of the novel receptor binding and species specificities of these bacteriocins has been driven by diversifying selection rather than diversifying recombination as suggested previously. Additionally, the structure of syringacin M reveals the presence of an active site calcium ion that is coordinated by a conserved aspartic acid side chain and is essential for catalytic activity. We show that mutation of this residue to alanine inactivates syringacin M and that the metal ion is absent from the structure of the mutant protein. Consistent with the presence of Ca2+ in the active site, we show that syringacin M activity is supported by Ca2+, along with Mg2+ and Mn2+, and the protein is catalytically inactive in the absence of these ions. PMID:22995910

  15. 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.

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

    Science.gov (United States)

    Sant'Anna, Voltaire; Quadros, Deoni A F; Motta, Amanda S; Brandelli, Adriano

    2013-12-01

    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 10(2) 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. Antibacterial activity of bacteriocin-like substance P34 on Listeria monocytogenes in chicken sausage

    Science.gov (United States)

    Sant’Anna, Voltaire; Quadros, Deoni A.F.; Motta, Amanda S.; Brandelli, Adriano

    2013-01-01

    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. PMID:24688506

  18. Purification and Characterization of a Novel Cold Shock Protein-Like Bacteriocin Synthesized by Bacillus thuringiensis

    Science.gov (United States)

    Huang, Tianpei; Zhang, Xiaojuan; Pan, Jieru; Su, Xiaoyu; Jin, Xin; Guan, Xiong

    2016-01-01

    Bacillus thuringiensis (Bt), one of the most successful biopesticides, may expand its potential by producing bacteriocins (thuricins). The aim of this study was to investigate the antimicrobial potential of a novel Bt bacteriocin, thuricin BtCspB, produced by Bt BRC-ZYR2. The results showed that this bacteriocin has a high similarity with cold-shock protein B (CspB). BtCspB lost its activity after proteinase K treatment; however it was active at 60 °C for 30 min and was stable in the pH range 5–7. The partial loss of activity after the treatments of lipase II and catalase were likely due to the change in BtCspB structure and the partial degradation of BtCspB, respectively. The loss of activity at high temperatures and the activity variation at different pHs were not due to degradation or large conformational change. BtCspB did not inhibit four probiotics. It was only active against B. cereus strains 0938 and ATCC 10987 with MIC values of 3.125 μg/mL and 0.781 μg/mL, and MBC values of 12.5 μg/mL and 6.25 μg/mL, respectively. Taken together, these results provide new insights into a novel cold shock protein-like bacteriocin, BtCspB, which displayed promise for its use in food preservation and treatment of B. cereus-associated diseases. PMID:27762322

  19. Pediocin SA-1: A selective bacteriocin for controlling Listeria monocytogenes in maize silages.

    Science.gov (United States)

    Amado, Isabel R; Fuciños, Clara; Fajardo, Paula; Pastrana, Lorenzo

    2016-10-01

    In this study, we assessed the potential as silage additive of a bacteriocin produced by Pediococcus acidilactici Northern Regional Research Laboratory (NRRL) B-5627 (pediocin SA-1). Maize was inoculated either with a bacterial starter alone (I) or in combination with the bacteriocin (IP), and untreated silage served as control. We monitored the products of fermentation (ethanol, and lactic and acetic acids), the microbial population, and the presence of the indicator strain Listeria monocytogenes Colección Española de Cultivos Tipo (CECT) 4032 (1×10(5) cfu/g) after 1, 2, 5, 8, 16, and 30d of ensiling. Our results indicated antilisterial activity of the bacteriocin, anticipating the disappearance of L. monocytogenes in IP compared with I and control silages. The PCR-denaturing gradient gel electrophoresis analysis revealed the addition of the bacteriocin did not affect the bacterial communities of the spontaneous fermentation, and the inoculant-containing bacteria (Lactobacillus plantarum, Lactobacillus buchneri, and Enterococcus faecium) were found in addition to the bacterial communities of untreated maize silages in I and IP silages. Both treatments increased the concentration of antimicrobial compounds (acetic acid, ethanol, and 1,2-propanodiol) and led to lower residual sugar contents compared with the control, which would provide enhanced aerobic stability. The fact that the identified species L. plantarum, L. buchneri, and E. faecium produce some of these inhibitory compounds, together with their persistence throughout the 30d of fermentation, suggest these bacteria could actively participate in the ensiling process. According to these results, pediocin SA-1 could be used as an additive to control the presence of L. monocytogenes in maize silages selectively, while improving their fermentative quality and eventually their aerobic stability. PMID:27522409

  20. Active polymers containing Lactobacillus curvatus CRL705 bacteriocins: effectiveness assessment in Wieners.

    Science.gov (United States)

    Blanco Massani, M; Molina, V; Sanchez, M; Renaud, V; Eisenberg, P; Vignolo, G

    2014-05-16

    Bacteriocins from lactic acid bacteria have potential as natural food preservatives. In this study two active (synthetic and gluten) films were obtained by the incorporation of lactocin 705 and lactocin AL705, bacteriocins produced by Lactobacillus curvatus CRL705 with antimicrobial activity against spoilage lactic acid bacteria and Listeria. Antimicrobial film effectiveness was determined in Wieners inoculated with Lactobacillus plantarum CRL691 and Listeria innocua 7 (10(4)CFU/g) stored at 5°C during 45days. Active and control (absence of bacteriocins) packages were prepared and bacterial counts in selective media were carried out. Visual inspection and pH measurement of Wieners were also performed. Typical growth of both inoculated microorganisms was observed in control packages which reached 10(6)-10(7)CFU/g at the end of storage period. In the active packages, L. innocua 7 was effectively inhibited (2.5 log cycles reduction at day 45), while L. plantarum CRL691 was only slightly inhibited (0.5 log cycles) up to the second week of storage, then counts around 10(6)-10(7)CFU/g were reached. Changes in pH values from 6.3 to 5.8 were produced and gas formation was observed in active and control packages. The low inhibitory effectiveness against lactic acid bacteria is in correlation with the low activity observed for lactocin 705 in the presence of fat; Wieners fat content (20-30%) may adversely affect antimicrobial activity. This study supports the feasibility of using polymers activated with L. curvatus CRL705 bacteriocins to control Listeria on the surface of Wieners and highlights the importance of evaluating antimicrobial packaging systems for each particular food application.

  1. 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...

  2. 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...

  3. 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...

  4. 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

  5. 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

  6. Analysis of Lactobacillus Products for Phages and Bacteriocins That Inhibit Vaginal Lactobacilli

    Directory of Open Access Journals (Sweden)

    Lin Tao

    1997-01-01

    Full Text Available Objective: Bacterial vaginosis is associated with an unexplained loss of vaginal lactobacilli. Previously, we have identified certain vaginal lactobacilli-released phages that can inhibit in vitro other vaginal lactobacilli. However, there is no apparent route for phages to be transmitted among women. The purpose of this study was to identify whether certain Lactobacillus products commonly used by women release phages or bacteriocins that can inhibit vaginal lactobacilli.

  7. Isolation and Characterization of a Broad Spectrum Bacteriocin from Bacillus amyloliquefaciens RX7

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    Kong Boon Lim

    2016-01-01

    Full Text Available We isolated a Bacillus strain, RX7, with inhibitory activity against Listeria monocytogenes from soil and identified it as Bacillus amyloliquefaciens based on 16S rRNA gene sequencing. The inhibitory activity was stable over a wide range of pH and was fully retained after 30 min at 80°C, after which it decreased gradually at higher temperatures. The activity was sensitive to the proteolytic action of α-chymotrypsin, proteinase-K, and trypsin, indicating its proteinaceous nature. This bacteriocin was active against a broad spectrum of bacteria and the fungus Candida albicans. Direct detection of antimicrobial activity on a sodium dodecyl sulfate-polyacrylamide gel suggested an apparent molecular mass of approximately 5 kDa. Ammonium sulfate precipitation and anion-exchange and gel permeation chromatography integrated with reverse phase-high-performance liquid chromatography were used for bacteriocin purification. Automated N-terminal Edman degradation of the purified RX7 bacteriocin recognized the first 15 amino acids as NH2-X-Ala-Trp-Tyr-Asp-Ile-Arg-Lys-Leu-Gly-Asn-Lys-Gly-Ala, where the letter X in the sequence indicates an unknown or nonstandard amino acid. Based on BLAST similarity search and multiple alignment analysis, the obtained partial sequence showed high homology with the two-peptide lantibiotic haloduracin (HalA1 from Bacillus halodurans, although at least two amino acids differed between the sequences. A time-kill study demonstrated a bactericidal mode of action of RX7 bacteriocin.

  8. 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...

  9. 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.

  10. 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

  11. 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

  12. 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.

  13. Purification and characterization of Plantaricin ZJ5, a new bacteriocin produced by Lactobacillus plantarum ZJ5.

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    Da-Feng Song

    Full Text Available The aim of this study is to investigate the antimicrobial potential of Lactobacillus plantarum ZJ5, a strain isolated from fermented mustard with a broad range of inhibitory activity against both Gram-positive and Gram-negative bacteria. Here we present the peptide plantaricin ZJ5 (PZJ5, which is an extreme pH and heat-stable. However, it can be digested by pepsin and proteinase K. This peptide has strong activity against Staphylococcus aureus. PZJ5 has been purified using a multi-step process, including ammonium sulfate precipitation, cation-exchange chromatography, hydrophobic interactions and reverse-phase chromatography. The molecular mass of the peptide was found to be 2572.9 Da using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS. The primary structure of this peptide was determined using amino acid sequencing and DNA sequencing, and these analyses revealed that the DNA sequence translated as a 44-residue precursor containing a 22-amino-acid N-terminal extension that was of the double-glycine type. The bacteriocin sequence exhibited no homology with known bacteriocins when compared with those available in the database, indicating that it was a new class IId bacteriocin. PZJ5 from a food-borne strain may be useful as a promising probiotic candidate.

  14. Determination of bacteriocin activity with bioassays carried out on solid and liquid substrates: assessing the factor "indicator microorganism"

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    Ambrosiadis Ioannis

    2006-10-01

    Full Text Available Abstract Background Successful application of growth inhibition techniques for quantitative determination of bacteriocins relies on the sensitivity of the applied indicator microorganism to the bacteriocin to which is exposed. However, information on indicator microorganisms' performance and comparisons in bacteriocin determination with bioassays is almost non-existing in the literature. The aim of the present work was to evaluate the parameter "indicator microorganism" in bioassays carried out on solid -agar diffusion assay- and liquid -turbidometric assay- substrates, applied in the quantification of the most studied bacteriocin nisin. Results The performance of characterized microorganisms of known sources, belonging to the genera of Lactobacillus, Pediococcus, Micrococcus and Leuconostoc, has been assessed in this work in the assays of plate agar diffusion and turbidometry. Dose responses and sensitivities were examined and compared over a range of assay variables in standard bacteriocin solutions, fermentation broth filtrates and processed food samples. Measurements on inhibition zones produced on agar plates were made by means of digital image analysis. The data produced were analyzed statistically using the ANOVA technique and pairwise comparisons tests. Sensitivity limits and linearity of responses to bacteriocin varied significantly among different test-microorganisms in both applied methods, the lower sensitivity limits depending on both the test-microorganism and the applied method. In both methods, however, only two of the nine tested microorganisms (Lactobacillus curvatus ATCC 51436 and Pediococcus acidilactici ATCC 25740 were sensitive to very low concentrations of the bacteriocin and produced a linear-type of response in all kinds of samples used in this work. In all cases, very low bacteriocin concentrations, e.g. 1 IU/ml nisin, were more accurately determined in the turbidometric assay. Conclusion The present work shows that in

  15. Isolation and partial characterization of a bacteriocin produced by Lactobacillus plantarum BM-1 isolated from a traditionally fermented Chinese meat product.

    Science.gov (United States)

    Zhang, Hongxing; Liu, Li; Hao, Yanling; Zhong, Siqiong; Liu, Hui; Han, Tao; Xie, Yuanhong

    2013-11-01

    Lactobacillus plantarum BM-1 isolated from a traditionally fermented Chinese meat product was found to produce a novel bacteriocin that is active against a wide range of gram-positive and gram-negative bacteria. Production of the bacteriocin BM-1 started early in the exponential phase and its maximum activity (5120 AU/mL) was recorded early during the stationary phase (16 hr). Bacteriocin BM-1 is sensitive to proteolytic enzymes but stable in the pH range of 2.0-10.0 and heat-resistant (15 min at 121°C). This bacteriocin was purified through pH-mediated cell adsorption-desorption and cation-exchange chromatography on an SP Sepharose Fast Flow column. The molecular weight of the purified bacteriocin BM-1 was determined to be 4638.142 Da by electrospray ionization Fourier transform mass spectrometry. Furthermore, the N-terminal amino acid sequence was obtained through automated Edman degradation and found to comprise the following 15 amino acid residues: H2 N-Lys-Tyr-Tyr-Gly-Asn-Gly-Val-Tyr-Val-Gly-Lys-His-Ser-Cys-Ser. Comparison of this sequence with that of other bacteriocins revealed that bacteriocin BM-1 contains the consensus YGNGV amino acid motif near the N-terminus. Based on its physicochemical characteristics, molecular weight, and N-terminal amino acid sequence, plantaricin BM-1 is a novel class IIa bacteriocin.

  16. Synthesis of lactococcin 972, a bacteriocin produced by Lactococcus lactis IPLA 972, depends on the expression of a plasmid-encoded bicistronic operon

    NARCIS (Netherlands)

    Martínez, B.; Fernández, M.; Suárez, J.E.; Rodríguez, A.

    1999-01-01

    Synthesis of lactococcin 972 is plasmid-encoded. An operon composed of two genes that encode pre-bacteriocin and a putative immunity protein has been identified. The first gene encodes a 91-residue polypeptide that is exported via a sec-dependent system to give the mature 66-aa bacteriocin. The immu

  17. LIKE IT ACID AND POOR: A STUDY OF ABIOTIC FACTORS INFLUENCING Streptococcus bovis HC5 GROWTH AND BACTERIOCIN PRODUCTION

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    Ana Andréa Teixeira Barbosa

    2015-04-01

    Full Text Available This study aimed to investigate the effect of pH, temperature, growth atmosphere and nutrient availability on bovicin HC5 production by Streptococcus bovis HC5. S. bovis HC5 grew well in complex and basal media under aerobic and anaerobic conditions, but greater bacteriocin yields were recovered from anaerobic cultures. Lactate production and glucose consumption increased if S. bovis HC5 cells were cultivated at pH 7.0 and at 45 ºC, but higher bovicin HC5 activity was recovered from cells grown in acidic conditions and at lower temperatures (39 ºC. Cultures maintained under continuous CO2 flow showed faster growth rates in basal media, but bacteriocin production was always higher if S. bovis was cultivated in anaerobic sealed tubes. These results suggest that acidic pH and anoxic conditions favor bovicin HC5 production by S. bovis HC5. S. bovis HC5 is a unique lactic acid bacterium in its ability to grow and produce high amounts of a potentially useful bacteriocin in simple media. Considering the constrains for bacteriocin production at commercial scale, it appears that bovicin HC5 production could be achieved at lower costs compared to other bacteriocins from lactic acid bacteria.

  18. 细菌素编码基因的定位分析%Primary genetic analysis of the bacteriocin locus

    Institute of Scientific and Technical Information of China (English)

    王辉; 孟祥晨

    2012-01-01

    The genes related to the production of bacteriocins always emerge in clusters: the operon structure is composed of structure genes, self-immunoreaction genes and genes encoding auxiliary protein. The structure genes encoding bacteriocins may be located in the plas-maids or genome DNA, in order to make sure the location of the genes encoding bacteriocins primarily, this paper introduced the methods of locating the genes encoding bacteriocins primarily, which formed the foundation of the further study of bacteriocins.%细菌素生物合成相关的基因经常成簇出现:结构基因、对自身产生免疫的基因及产生辅助蛋白质的基因组成操纵子结构,其中结构基因是细菌素编码基因,它可能在质粒上也可能在染色体上,为了初步定位细菌素编码基因是在质粒上还是染色体上,综述细菌素编码基因的初步定位方法,为深入研究细菌素提供依据.

  19. 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.

  20. Partial Characterization of an Anti-Candida albicans Bacteriocin Produced by a Marine Strain of Bacillus sp., Sh10

    Directory of Open Access Journals (Sweden)

    Fatemeh Shayesteh

    2015-09-01

    Full Text Available The bacteriocin-producing strain Bacillus sp., Sh10, isolated from the marine environment, exhibited a broad spectrum of antimicrobial activity against different food spoilage and human pathogens, with a maximum inhibitory activity against Candida albicans. The inhibitory compound was sensitive to trypsin but resistant to proteinase K, lysozyme, lipase and &alpha-amylase. It was heat-stable and remained its activity after autoclaving. In addition, the antimicrobial substance demonstrated striking stability at low temperatures (4 and -20°C for up to one year and retained its activity in a wide pH range from 2 to 11. It was also stable and active in the presence of different surfactants, solvents and heavy metals. Analysis of the partially purified bacteriocin by SDS-PAGE showed an apparent molecular weight of ~11 KDa. This study reveals a remarkable potential of this bacteriocin to be used as a food preservative.

  1. Bacteriocin as Weapons in the Marine Animal-Associated Bacteria Warfare: Inventory and Potential Applications as an Aquaculture Probiotic

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    Florie Desriac

    2010-04-01

    Full Text Available As the association of marine animals with bacteria has become more commonly recognized, researchers have increasingly questioned whether these animals actually produce many of the bioactive compounds originally isolated from them. Bacteriocins, ribosomally synthesized antibiotic peptides, constitute one of the most potent weapons to fight against pathogen infections. Indeed, bacteriocinogenic bacteria may prevent pathogen dissemination by occupying the same ecological niche. Bacteriocinogenic strains associated with marine animals are a relevant source for isolation of probiotics. This review draws up an inventory of the marine bacteriocinogenic strains isolated from animal-associated microbial communities, known to date. Bacteriocin-like inhibitory substances (BLIS and fully-characterized bacteriocins are described. Finally, their applications as probiotics in aquaculture are discussed.

  2. Large scale preparation and application of bacteriocins%细菌素的制备及其应用

    Institute of Scientific and Technical Information of China (English)

    方佳琪; 别怀周; 陈晓琳; 张明

    2011-01-01

    In recent years, bacteriocins that can inhibit or kill the growth of some bacteria have a wide range of practical application in food preservation, disease treatment and many other related aspects were found, and the preparation methods of bacteriocin were widely reported. This article outlines the preparation methods of bacteriocins and its application in many fields.%近年来,具有抑菌活性的细菌素被发现在食品防腐保鲜、疾病治疗和其他许多相关方面有着广泛的应用价值,各种制备细菌素的方法 也被广泛报道.本文概述了细菌素的制备方法 以及其在诸多领域中的应用.

  3. 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.

  4. 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.

  5. Screening of marine bacteria with bacteriocin-like activities and probiotic potential for ornate spiny lobster (Panulirus ornatus) juveniles.

    Science.gov (United States)

    Nguyen, Van Duy; Pham, Thu Thuy; Nguyen, Thi Hai Thanh; Nguyen, Thi Thanh Xuan; Hoj, Lone

    2014-09-01

    Bacteriocins are ribosomally synthesized antimicrobial peptides, which have been found in diverse bacterial species of terrestrial origins and some from the sea. New bacteriocins with new characteristics, new origins and new applications are likely still awaiting discovery. The present study screened bacteria isolated from marine animals of interest to the aquaculture industry for antimicrobial and bacteriocin-like activities in order to uncover biodiversity of bacteriocin producers, and explore the potential application in aquaculture. In total, 24 of 100 screened isolates showed antimicrobial activities and 7 of these exerted bacteriocin-like activities. Sequencing of 16S rRNA genes identified the isolates as members of the six genera Proteus, Providencia, Klebsiella, Alcaligenes, Bacillus and Enterococcus. In some cases, further analysis of housekeeping genes, rpoB for Proteus and recA for Klebsiella, as well as biochemical tests was necessary for identification to species level, and some of the Proteus isolates may represent novel species. The seven bacteriocinogenic isolates showed a wide antimicrobial spectrum against foodborne and animal pathogens, which opens the way to their potential use as marine drugs and probiotics in food, aquaculture, livestock and clinical settings. As a case study, the protective effect of shortlisted bacteriocinogenic isolates were tested in aquaculture-raised spiny lobster (Panulirus ornatus) juveniles. A single-strain (Bacillus pumilus B3.10.2B) and a three-strain (B. pumilus B3.10.2B, Bacillus cereus D9, Lactobacillus plantarum T13) probiotic preparation were added to the feed of Panulirus ornatus juveniles, which were subsequently challenged with the pathogen Vibrio owensii DY05. Juveniles in the probiotic treatments displayed increased growth and reduced feed conversion rates after 60 days, and increased survival rate after pathogen challenge relative to the control. This study represents the first evidence of bacteriocin

  6. 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...

  7. 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

  8. In Vitro Evaluation of Bacteriocins Activity Against Listeria monocytogenes Biofilm Formation.

    Science.gov (United States)

    Camargo, Anderson Carlos; de Paula, Otávio Almeida Lino; Todorov, Svetoslav Dimitrov; Nero, Luís Augusto

    2016-03-01

    The present study aimed to assess the activity of cell-free supernatant (CFS) containing bacteriocins on the formation and maintenance of biofilms developed by Listeria monocytogenes, and the associated effect of bacteriocins and ethylene-diamine-tetra-acetic acid (EDTA) on the formed biofilm. CFS from 9 lactic acid bacteria (LAB) strains was tested for inhibitory activity against 85 L. monocytogenes isolates and 21 LAB strains. Then, 12 L. monocytogenes strains were selected based on genetic profiles and sensitivity to CFS and were subjected to an in vitro assay to assess biofilm formation in microtiter plates, considering different culture media and incubation conditions. Based on these results, 6 L. monocytogenes strains were subjected to the same in vitro procedure to assess biofilm formation, being co-inoculated with CFS. In addition, these strains were subjected to the same in vitro procedure, modified by adding the CFS after biofilm formation. Relevant decrease in biofilm formation was observed in the first experiment, but CFS added after biofilm formation did not eliminate them. CFS from Lactobacillus curvatus ET31 were selected due to its anti-biofilm activity, being associated to EDTA at different concentrations and tested for biofilm control of three strains of L. monocytogenes, using the same in vitro procedure described previously. Concentrated bacteriocin presented poor performance in eliminating formed biofilms, and EDTA concentration presented no evident interference on biofilm elimination. Twelve selected L. monocytogenes strains were positive for investigated virulence makers and negative for luxS gene, recognized as being involved in biofilm formation. Selected L. monocytogenes strains were able to produce biofilms under different conditions. CFSs have the potential to prevent biofilm formation, but they were not able to destroy already formed biofilms. Nevertheless, low concentrations of CFS combined with EDTA caused a relevant reduction in

  9. Characterization of a bacteriocin produced by Lactobacillus sakei R1333 isolated from smoked salmon.

    Science.gov (United States)

    Todorov, Svetoslav D; Rachman, Cinta; Fourrier, Angélique; Dicks, Leon M T; van Reenen, Carol A; Prévost, Herve; Dousset, Xavier

    2011-02-01

    Strain R1333, isolated from commercially available smoked salmon, was identified as Lactobacillus sakei based on biochemical tests, sugar fermentation reactions (API 50 CHL), PCR with species-specific primers and sequencing of the 16S rRNA gene. Strain R1333 produces a 3811 kDa class IIa bacteriocin, active against Streptococcus caprinus, Streptococcus macedonicus, Streptococcus spp., L. sakei, Lactococcus lactis subsp. lactis, Listeria innocua, Listeria ivanovii subsp. ivanovii and Listeria monocytogenes. The mode of activity against L. innocua 2030C and L. ivanovii subsp. ivanovii ATCC 19119 was bactericidal, resulting in cell lysis and enzyme- and DNA-leakage. The highest level of activity (1600 AU/mL) was recorded when cells were grown at 30°C in MRS broth (initial pH 6.5). Only 800 AU/mL was recorded when strain R1333 was grown in MRS without Tween 80. Lower levels of bacteriocin production were recorded when strain R1333 was grown in MRS at 20°C. Peptide R1333 adsorbs at low levels (200 AU/mL) to producer cells. Purification of bacteriocin R1333 was performed by 60% ammonium sulfate precipitation, followed by separation on a SepPak C(18) column and reverse-phase HPLC on a Nucleosil C(18) column with a linear gradient from 0.1% TFA to 90% acetonitryl. A molecular mass of 3811 kDa was determined by mass spectrometry. Based on mass spectrometry and sequencing of the PCR amplified fragment targeting the sakG gene, L. sakei R1333 is a potential producer of sakacin G. This is the first report of the identification of sakacin G produced by L. sakei isolated from smoked salmon.

  10. 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.

  11. Effects of nitrogen sources on bacteriocin production by Enterococcus faecium A 2000.

    Science.gov (United States)

    Pantev, A; Kabadjova, P; Valcheva, R; Danova, S; Dousset, X; Haertlé, T; Chobert, J M; Ivanova, I

    2002-01-01

    The production of a novel broad-spectrum antimicrobial peptide enterococcin A 2000, active against Gram-positive and Gram-negative microorganisms including Listeria subsp. and Escherichia coli, by Enterococcus faecium strain A 2000 isolated from the surface of traditional Bulgarian yellow cheese "kash-kaval" is considerably influenced by complex nitrogen sources in the production medium. Medium components, especially peptone and yeast extract, and their concentration contributed to the increase in bacteriocin production during the stationary phase (16-46 h) of cultivation even in the absence of one of the components present in the basal cultivation MRS medium.

  12. 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...

  13. 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 ...

  14. The effectiveness of novel bacteriocin derived from Escherichia coli colonized in the fermented pineapple Ananas comosus (L. Merr. against pathogenic bacteria isolated from aquaculture sites

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    S. W. Lee

    2014-11-01

    Full Text Available Aim: The aim was to evaluate antimicrobial property of bacteriocin isolated from Escherichia coli against pathogenic bacteria from aquaculture sites. Materials and Methods: E. coli was isolated from fermented pineapple Ananas comosus using eosin methylene blue agar. The antimicrobial activity of the isolated E. coli was screened using hole-plate diffusion method. The bacterial strain that showed the widest inhibition zone was selected and grown in tryptic soy broth, followed by partial purification of bacteriocin by using ammonium sulphate. Bacteriocin derived from the E. coli was subjected to the antimicrobial test against 55 bacteria strains namely Aeromonas hydrophila (n=10, Citrobacter freundii (n=5, Edwardsiella tarda (n=10, Flavobacterium spp. (n=10, Pseudomonas spp. (n=10, Vibrio parahaemolyticus (n=5 and Vibrio alginolyticus (n=5 by using twofold broth microdilution method to determine minimum inhibitory concentration (MIC values of the bacteriocin against the tested bacteria. Results: The results of the present study showed that the MIC values of the partially purified bacteriocin against present pathogenic bacteria isolates ranged from 7.81 to 31.25 ppm whereas the MIC values of kanamycin (positive control ranged from 15.63 to 125 ppm. Conclusion: The results of the present study showed the bacteriocin derived from E. coli can control all the present bacterial isolates indicating the huge potential of the bacteriocin as a new antimicrobial agent for aquaculture uses.

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

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    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.

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

    Science.gov (United States)

    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 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. PMID:24159285

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

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    Chuong Nguyen

    2016-01-01

    Full Text Available 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.

  18. 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.

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

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    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.

  20. Characterization of Bacteriocin like inhibitory substance produced by a new Strain Brevibacillus borstelensis AG1 Isolated from 'Marcha'

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    Nivedita Sharma

    2014-09-01

    Full Text Available In the present study, a bacterium isolated from Marcha- a herbal cake used as traditional starter culture to ferment local wine in North East India, was evaluated for bacteriocin like inhibitory substance production and was tested against six food borne/spoilage causing pathogens viz. Listeria monocytogenes MTCC 839, Bacillus subtilis MTCC 121, Clostridium perfringens MTCC 450, Staphylococcus aureus, Lactobacillus plantarum and Leuconostoc mesenteroides MTCC 107 by using bit/disc method followed by well diffusion method. The bacterial isolate was identified as Brevibacillus borstelensis on the basis of phenotypic, biochemical and molecular characteristics using 16Sr RNA gene technique. Bacteriocin like inhibitory substance produced by Brevibacillus borstelensis AG1 was purified by gel exclusion chromatography. The molecular mass of the Brevibacillus borstelensis AG1 was found to be 12 kDa. Purified bacteriocin like inhibitory substance of Brevibacillus borstelensis was further characterized by studying the effect of temperature, pH, proteolytic enzyme and stability. Bacteriocin like inhibitory substance was found to be thermostable upto 100 °C, active at neutral pH, sensitive to trypsin, and partially stable till third week of storage thus showing a bright prospective to be used as a potential food biopreservative.

  1. 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

  2. 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.

  3. Purification and characterization of plantaricin 163, a novel bacteriocin produced by Lactobacillus plantarum 163 isolated from traditional Chinese fermented vegetables.

    Science.gov (United States)

    Hu, Meizhong; Zhao, Haizhen; Zhang, Chong; Yu, Jiansheng; Lu, Zhaoxin

    2013-11-27

    Presumptive lactic acid bacteria (LAB) strains isolated from traditional Chinese fermented vegetables were screened for bacteriocin production. A novel bacteriocin-producing strain, Lactobacillus plantarum 163, was identified on the basis of its physiobiochemical characteristics and characterized by 16S rDNA sequencing. The novel bacteriocin, plantaricin 163, produced by Lb. plantarum 163 was purified by salt precipitation, gel filtration, and reverse-phase high-performance liquid chromatography (RP-HPLC). Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) analysis of plantaricin 163 revealed the molecular weight to be 3553.2 Da. The complete amino acid sequence showed VFHAYSARGNYYGNCPANWPSCRNNYKSAGGK, and no similarity to known bacteriocins was found. Plantaricin 163 was highly thermostable (20 min, 121 °C), active in the presence of acidic pH (3-5), sensitive to protease, and exhibited broad-spectrum antimicrobial activity against LAB and other tested Gram-positive and Gram-negative bacteria. The results suggest that plantaricin 163 may be employed as a biopreservative in the food industry.

  4. Outgrowth inhibition of Clostridium beijerinckii spores by a bacteriocin-producing lactic culture in ovine milk cheese.

    Science.gov (United States)

    Garde, Sonia; Avila, Marta; Arias, Ramón; Gaya, Pilar; Nuñez, Manuel

    2011-10-17

    In the manufacture of model cheeses, ovine milk was deliberately contaminated with spores of Clostridium beijerinckii INIA 63, a wild isolate from Manchego cheese with late blowing defect, and inoculated with nisin- and lacticin 481-producing Lactococcus lactis subsp. lactis INIA 415 as starter, to test its potential to prevent the late blowing defect, or with L. lactis subsp. lactis INIA 415-2, a spontaneous mutant not producing bacteriocins. Cheeses made individually with the lactococcal strains, without clostridial spores, served as controls. Cheese made with clostridial spores and L. lactis subsp. lactis INIA 415-2 showed late blowing defect after 120days of ripening. Spoilt cheese also showed lower concentrations of lactic acid, and higher levels of acetic, propionic and butyric acids, and of other volatile compounds such as 2-propanol and 1-butanol, than control cheese. In addition, cheese made with the bacteriocin producer did not show any late blowing symptoms, despite its spore counts similar to those of blown cheese, pointing to outgrowth inhibition of C. beijerinckii spores by bacteriocins. Besides, cheese made with the bacteriocin producer showed similar concentrations of lactic acid and volatile compounds than control cheese. Inclusion of L. lactis subsp. lactis INIA 415 in starter cultures seems a feasible method to prevent late blowing defect in cheese without altering its sensory characteristics. PMID:21849216

  5. Lectin-like bacteriocins from Pseudomonas spp. utilise D-rhamnose containing lipopolysaccharide as a cellular receptor.

    Science.gov (United States)

    McCaughey, Laura C; Grinter, Rhys; Josts, Inokentijs; Roszak, Aleksander W; Waløen, Kai I; Cogdell, Richard J; Milner, Joel; Evans, Tom; Kelly, Sharon; Tucker, Nicholas P; Byron, Olwyn; Smith, Brian; Walker, Daniel

    2014-02-01

    Lectin-like bacteriocins consist of tandem monocot mannose-binding domains and display a genus-specific killing activity. Here we show that pyocin L1, a novel member of this family from Pseudomonas aeruginosa, targets susceptible strains of this species through recognition of the common polysaccharide antigen (CPA) of P. aeruginosa lipopolysaccharide that is predominantly a homopolymer of D-rhamnose. Structural and biophysical analyses show that recognition of CPA occurs through the C-terminal carbohydrate-binding domain of pyocin L1 and that this interaction is a prerequisite for bactericidal activity. Further to this, we show that the previously described lectin-like bacteriocin putidacin L1 shows a similar carbohydrate-binding specificity, indicating that oligosaccharides containing D-rhamnose and not D-mannose, as was previously thought, are the physiologically relevant ligands for this group of bacteriocins. The widespread inclusion of d-rhamnose in the lipopolysaccharide of members of the genus Pseudomonas explains the unusual genus-specific activity of the lectin-like bacteriocins.

  6. Lectin-like bacteriocins from Pseudomonas spp. utilise D-rhamnose containing lipopolysaccharide as a cellular receptor.

    Directory of Open Access Journals (Sweden)

    Laura C McCaughey

    2014-02-01

    Full Text Available Lectin-like bacteriocins consist of tandem monocot mannose-binding domains and display a genus-specific killing activity. Here we show that pyocin L1, a novel member of this family from Pseudomonas aeruginosa, targets susceptible strains of this species through recognition of the common polysaccharide antigen (CPA of P. aeruginosa lipopolysaccharide that is predominantly a homopolymer of D-rhamnose. Structural and biophysical analyses show that recognition of CPA occurs through the C-terminal carbohydrate-binding domain of pyocin L1 and that this interaction is a prerequisite for bactericidal activity. Further to this, we show that the previously described lectin-like bacteriocin putidacin L1 shows a similar carbohydrate-binding specificity, indicating that oligosaccharides containing D-rhamnose and not D-mannose, as was previously thought, are the physiologically relevant ligands for this group of bacteriocins. The widespread inclusion of d-rhamnose in the lipopolysaccharide of members of the genus Pseudomonas explains the unusual genus-specific activity of the lectin-like bacteriocins.

  7. Bacteriocin production and resistance to drugs are advantageous features for Lactobacillus acidophilus La-14, a potential probiotic strain.

    Science.gov (United States)

    Todorov, Svetoslav Dimitrov; Furtado, Danielle Nader; Saad, Susana Marta Isay; Gombossy de Melo Franco, Bernadette Dora

    2011-10-01

    L. acidophilus La-14 produces bacteriocin active against L. monocytogenes ScottA (1600 AU/ml) in MRS broth at 30°C or 37°C. The bacteriocin proved inhibitory to different serological types of Listeria spp. Antimicrobial activity was completely lost after treatment of the cell-free supernatant with proteolytic enzymes. Addition of bacteriocin produced by L. acidophilus La-14 to a 3 h-old culture of L. monocytogenes ScottA repressed cell growth in the following 8h. Treatment of stationary phase cells of L. monocytogenes ScottA (107-108 CFU/ml) by the bacteriocin resulted in growth inhibition. Growth of L. acidophilus La-14 was not inhibited by commercial drugs from different generic groups, including nonsteroidal anti-inflammatory drugs (NSAID) containing diclofenac potassium or ibuprofen arginine. Only one non-antibiotic drug tested, Atlansil (an antiarrhythmic agent), had an inhibitory effect on L. acidophilus La-14 with MIC of 2.5 mg/ml. L. acidophilus La-14 was not affected by drugs containing sodium or potassium diclofenac. L. acidophilus La-14 shows a good resistance to several drugs and may be applied in combination for therapeutic use.

  8. 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

  9. In Vitro Evaluation of Bacteriocin-Like Inhibitory Substances Produced by Lactic Acid Bacteria Isolated During Traditional Sicilian Cheese Making

    Science.gov (United States)

    Macaluso, Giusi; Fiorenza, Gerlando; Gaglio, Raimondo; Mancuso, Isabella

    2016-01-01

    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 (a-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. 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.

  11. Mutational analysis and chemical modification of Cys24 of lactococcin B, a bacteriocin produced by Lactococcus lactis

    NARCIS (Netherlands)

    Venema, K; Dost, MHR; Kok, J; Dost, Michiel H.R.; Venema, Gerhardus

    1996-01-01

    Using site-directed mutagenesis the single cysteine residue at position 24 of lactococcin B was replaced by all other possible amino acids. Most of these mutant molecules retained bacteriocin activity, with the exception of those in which cysteine was replaced by a positively charged amino acid. Thi

  12. Bacteriocin AS-48 binding to model membranes and pore formation as revealed by coarse-grained simulations

    NARCIS (Netherlands)

    Cruz, Victor L.; Ramos, Javier; Martinez-Salazar, Javier; Melo, Manuel N.

    2013-01-01

    Bacteriocin AS-48 is a membrane-interacting peptide that acts as a broad-spectrum antimicrobial against Gram-positive and Gram-negative bacteria. Prior Nuclear Magnetic Resonance experiments and the high resolution crystal structure of AS-48 have suggested a mechanism for the molecular activity of A

  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. 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.

  15. 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.

  16. Antagonistic Potential of Lactobacillus Spp against Enteropathogenic Bacteria; Purification and Characterization of their Bacteriocins

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    Asha

    2012-10-01

    Full Text Available In the present study, Lactobacillus (160 isolates were isolated from curd sample. The isolates were aimed to analyze the antibacterial potential against Escherichia coli, Vibrio cholerae sub sp., ogawa, V. cholerae sub sp., inaba, Klebsiella sp., Proteus sp. and Shigella dysenteriae. All the isolates were inhibiting the tested Enteropathogenic bacteria except S. dysenteriae. Lactobacillus isolates produced highest inhibition zone (30 to 37 mm against V. cholerae sub sp., inaba and Klebsiella sp., of the 160 isolates only ten Lactobacillus isolates (L1- L10 were used for the production of bacteriocins, purified by ammonium sulphate precipitation and ion exchange (DEAE cellulose chromatography. Maximum bacteriocin activity has been observed with Lf3 against V. cholerae ssp Inaba at 30°C, pH 6.0, 1.5 to 2.0% Na Cl/18 h in addition to L8, L9 and L10 (MW 100 to 106 KDa and Lf3 was found to be the most prominent potential isolate.

  17. A peptide factor secreted by Staphylococcus pseudintermedius exhibits properties of both bacteriocins and virulence factors

    Science.gov (United States)

    Wladyka, Benedykt; Piejko, Marcin; Bzowska, Monika; Pieta, Piotr; Krzysik, Monika; Mazurek, Łukasz; Guevara-Lora, Ibeth; Bukowski, Michał; Sabat, Artur J.; Friedrich, Alexander W.; Bonar, Emilia; Międzobrodzki, Jacek; Dubin, Adam; Mak, Paweł

    2015-01-01

    Staphylococcus pseudintermedius is a common commensal bacterium colonizing the skin and mucosal surfaces of household animals. However, it has recently emerged as a dangerous opportunistic pathogen, comparable to S. aureus for humans. The epidemiological situation is further complicated by the increasing number of methicillin-resistant S. pseudintermedius infections and evidence of gene transmission driving antibiotic resistance between staphylococci colonizing human and zoonotic hosts. In the present study, we describe a unique peptide, BacSp222, that possesses features characteristic of both bacteriocins and virulence factors. BacSp222 is secreted in high quantities by S. pseudintermedius strain 222 isolated from dog skin lesions. This linear, fifty-amino-acid highly cationic peptide is plasmid-encoded and does not exhibit significant sequence similarities to any other known peptides or proteins. BacSp222 kills gram-positive bacteria (at doses ranging from 0.1 to several micromol/l) but also demonstrates significant cytotoxic activities towards eukaryotic cells at slightly higher concentrations. Moreover, at nanomolar concentrations, the peptide also possesses modulatory properties, efficiently enhancing interferon gamma-induced nitric oxide release in murine macrophage-like cell lines. BacSp222 appears to be one of the first examples of multifunctional peptides that breaks the convention of splitting bacteriocins and virulence factors into two unrelated groups. PMID:26411997

  18. Development of bioactive food packaging materials using immobilised bacteriocins lacticin 3147 and nisaplin.

    Science.gov (United States)

    Scannell, A G; Hill, C; Ross, R P; Marx, S; Hartmeier, W; Elke; Arendt, K

    2000-09-25

    Immobilisation of the bacteriocins nisin and lacticin 3147 to packaging materials was investigated. Stability of both cellulose-based bioactive inserts and anti-microbial polyethylene/polyamide pouches was examined over time. Anti-microbial activity against the indicator strain Lactococcus lactis subsp. lactis HP, in addition to Listeria innocua DPC 1770 and Staphylococcus aureus MMPR3 was observed for all bacteriocin-adsorbed materials. Activity retention of the inserts showed an initial decrease in the first week of storage but remained stable for the remaining 3 months of the trial. However, adsorption of lacticin 3147 to plastic film was unsuccessful, nisin bound well and the resulting film maintained its activity for 3-month period, both at room temperature and under refrigeration. When applied to food systems, the anti-microbial packaging reduced the population of lactic acid bacteria in sliced cheese and ham stored in modified atmosphere packaging (MAP) at refrigeration temperatures, thus extending the shelf life. Nisin-adsorbed bioactive inserts reduced levels of Listeria innocua by > or = 2 log units in both products, and Staphylococcus aureus by approximately 1.5 log units in cheese, and approximately 2.8 log units in ham. Similar reductions were observed in cheese vacuum-packaged in nisin-adsorbed pouches.

  19. 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

  20. 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

  1. 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.

  2. Behavior of Listeria monocytogenes and Staphylococcus aureus in yogurt fermented with a bacteriocin-producing thermophilic starter.

    Science.gov (United States)

    Benkerroum, Noreddine; Oubel, Hafida; Mimoun, Lamiae Ben

    2002-05-01

    Streptococcus salivarius subsp. thermophilus B producing a bacteriocin active against Listeria monocytogenes ATCC 7644 and Staphylococcus aureus SAD 30 was isolated from bakery yeast. The bacteriocin was partially purified by an adsorption/desorption technique, and its spectrum of action was compared to that of a neutralized cell-free supernatant (CFS). Although the CFS inhibited a number of gram-positive and -negative bacteria of health and spoilage significance, the spectrum of action of the partially purified bacteriocin was limited to gram-positive bacteria. L. monocytogenes was the most sensitive to both preparations. The bacteriocin-producing streptococcal strain was used in combination with a Bac- Lactobacillus delbrueckii subsp. bulgaricus CY strain isolated from commercial yogurt to assess the effectiveness of the resulting thermophilic starter in controlling L. monocytogenes and S. aureus in yogurt during fermentation and storage at refrigeration (ca. 7 degrees C) or abuse (ca. 22 degrees C) temperature. Yogurt samples were contaminated with L. monocytogenes or S. aureus to the approximate levels of 10(3) and 10(6) CFU/ml of milk, respectively. The results showed that in situ bacteriocin production was more active against L. monocytogenes than against S. aureus in vitro and in contaminated samples. While L. monocytogenes leveled off below the detectable limit in a 1-ml sample of yogurt within 24 h of processing, S. aureus survived in Bac+ and Bac- samples during 10 days of storage at room temperature (ca. 22 degrees C). Use of a Bac+ starter resulted in a 5-day extension of the shelf life.

  3. 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.;

    2003-01-01

    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...

  4. 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.

  5. Lyophilized Carnobacterium divergens AS7 bacteriocin preparation improves performance of broiler chickens challenged with Clostridium perfringens

    DEFF Research Database (Denmark)

    Jozefiak, D; Sip, A; Rutkowski, A;

    2012-01-01

    The present study aimed to investigate the effects of Carnobacterium divergens AS7 bacteriocin (divercin AS7) on growth performance, digestibility, fermentation processes, selected microbial populations, and histomorphology in broiler chickens challenged with a mixture of 3 Clostridium perfringen...

  6. 乳酸菌细菌素作用机理的研究%Overview of the Mechanism of Action of Lactis Acid Bacteria Bacteriocins

    Institute of Scientific and Technical Information of China (English)

    李瑞胜; 别怀周; 张明

    2012-01-01

    Lactis acid bacteria bacteriocin acts as a natural food preservative to inhibit or kill the pathogenic bacteria and spoilage microorganism of food. The research about the mechanism of bacteriocin has laid a foundation for ihe application of bacteriocin in food* In this paper, the mechanism of class I and class II bacteriocins were reviewed.%乳酸茵细菌素可抑制或杀死食品中的病原菌和腐败茵,是天然的食品防腐剂对乳酸菌细菌素作用机理的研究可为其在食品工业中的应用奠定基础,就Ⅰ类和Ⅱ类细菌素的作用机理进行了综述.

  7. Bacteriocins from Lactobacillus plantarum - production, genetic organization and mode of action: produção, organização genética e modo de ação.

    Science.gov (United States)

    Todorov, Svetoslav D

    2009-04-01

    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.

  8. Release of Bacteriocins from Nanofibers Prepared with Combinations of Poly(d,l-lactide) (PDLLA) and Poly(Ethylene Oxide) (PEO)

    OpenAIRE

    Leon Dicks; Osama Bshena; Bert Klumperman; Tiaan Heunis

    2011-01-01

    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...

  9. 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

  10. 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.

  11. 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. ...

  12. 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.

  13. 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.

  14. 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...

  15. 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...

  16. Extraction Effect of Different Extractant on Crude Bacteriocin%不同提取剂对粗细菌素提取效果的影响

    Institute of Scientific and Technical Information of China (English)

    许亦峰; 罗晓蕾; 施碧红

    2013-01-01

    The method for extracting the crude bacteriocin was set up through trial and error. Compared the advantages and disadvantages of the acid precipitation and the ammonium sulfate precipitation method for the extracting capacity and the activity remained of crude bacteriocin. Results showed that more bacteriocin was obtained by acid precipitation than by ammonium sulfate precipitation. The crude protein content of the bacteriocin was increased by 28.7% , the specific activity of crude bacteriocin obtained by acid precipitation was increased 55.5% , and the titer of bacteriocin is 2 times of that of by ammonium sulfate precipitation. The precipitations were further extracted by different solvents; as a result, the chloroform shows the best result based on the bacteriocin yield and activity.%摸索并建立了粗提细菌素的方法.从粗提细菌素的能力和活性保留两个方面,比较了酸沉淀法和硫酸铵沉淀法的优劣.结果发现,相对于硫酸铵沉淀法,酸沉淀法能够获得更多的粗细菌素,蛋白总量提高了28.7%.且酸沉淀法得到的粗细菌素的比活性比硫酸铵沉淀法提高了55.5%,单位效价是硫酸铵沉淀法的2倍.比较了不同有机溶剂抽提以上沉淀物,综合考虑细菌素得率及活性,发现三氯甲烷的抽提效果较好.

  17. Characterization of a noncytotoxic bacteriocin from probiotic Lactobacillus plantarum DM5 with potential as a food preservative.

    Science.gov (United States)

    Das, Deeplina; Goyal, Arun

    2014-10-01

    The aim of this work was to purify and characterize the bacteriocin produced by probiotic Lactobacillus plantarum DM5 in order to evaluate its potential as nutraceuticals. Lb. plantarum DM5 exhibited in vitro probiotic properties such as high resistance to gastric juice and bile salt, adherence to human adenocarcinoma (HT-29) cells, bile salt hydrolase and cholesterol assimilation activity. Moreover, Lb. plantarum DM5 showed bacteriocin activity against several major food borne pathogens. Zymogram analysis of purified bacteriocin (plantaricin DM5) showed a molecular size of ∼15.2 kDa. Plantaricin DM5 was sensitive to proteolytic enzymes but stable in the pH range of 2.0-10.0, and it was heat resistant (121 °C for 15 min) and remained active upon treatment with surfactants and detergents. Cytotoxicity analysis of plantaricin DM5 on human embryonic kidney 293 (HEK 293) and human cervical cancer (HeLa) cell lines revealed its nontoxic and biocompatible nature. To the best of our knowledge, this is the first study on the isolated strain expressing probiotic properties and broad antimicrobial activity without any cytotoxic effect on mammalian cells from indigenous fermented beverage Marcha from India, and thus contributes to the food industry as a novel bio-preservant.

  18. Antimicrobial activity and partial characterization of bacteriocin-like inhibitory substances produced by Lactobacillus spp. isolated from artisanal Mexican cheese.

    Science.gov (United States)

    Heredia-Castro, Priscilia Y; Méndez-Romero, José I; Hernández-Mendoza, Adrián; Acedo-Félix, Evelia; González-Córdova, Aarón F; Vallejo-Cordoba, Belinda

    2015-12-01

    Lactobacillus spp. from Mexican Cocido cheese were shown to produce bacteriocin-like substances (BLS) active against Staphylococcus aureus,Listeria innocua,Escherichia coli, andSalmonella typhimurium by using the disk diffusion method. Crude extracts of Lactobacillus fermentum showed strong inhibitory activity against Staph. aureus, L. innocua, E. coli, and Salmonella cholerae. Complete inactivation of antimicrobial activity was observed after treatment of crude extracts with proteinase K, pronase, papain, trypsin, and lysozyme, confirming their proteinaceous nature. However, antimicrobial activity was partly lost for some of the crude extracts when treated with α-amylase, indicating that carbohydrate moieties were involved. The antimicrobial activity of the crude extracts was stable at 65°C for 30min over a wide pH range (2-8), and addition of potassium chloride, sodium citrate, ethanol, and butanol did not affect antibacterial activity. However, antimicrobial activity was lost after heating at 121°C for 15min, addition of methanol or Tween 80. Fourteen out of 18 Lactobacillus spp. showed antimicrobial activity against different test microorganisms, and 12 presented bacteriocin-like substances. Generation time and growth rate parameters indicated that the antimicrobial activity of crude extracts from 3 different strains was effective against the 4 indicator microorganisms. One of the crude extracts showed inhibition not only against gram-positive but also against gram-negative bacteria. Bacteriocin-like substances produced by this specific Lactobacillus strain showed potential for application as a food biopreservative.

  19. 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.

  20. 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.

  1. 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

  2. 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

    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 physiological state of sessile and planktonic L. monocytogenes (strains EGDe and N53-1) during co-culturing with plantaricin-producing L. plantarum (strains BFE 5092 and PCS 20) was investigated using fluorescence ratio imaging microscopy (FRIM). Mono-cultures of L. monocytogenes were used as control...... affected pHi of L. monocytogenes N53-1 with only 20% of the cells being able to maintain pHi in the physiological optimal range with pH > 7 and 52% of the cells with pHi ~ pHex, showing that the cells had no proton gradient towards the environment. The effect on L. monocytogenes EGDe was less pronounced...

  3. 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.

  4. 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

  5. 细菌素的分子生物学研究进展%Development of Biological and Molecular Characterization of Bacteriocins

    Institute of Scientific and Technical Information of China (English)

    崔德凤; 周波; 张永红

    2011-01-01

    Bacteriocins are a heterogeneous group of ribosomally synthesized antibacterial peptides or protein from some bacteria species. They are expected to become alternatives of food additives and antibiotics for their broad-spectrum antimicrobial activity, This paper reviews the bacteriocins molecular structure and function, genotyping, biosynthesis and their gene regulation, mode of antibacterial action and bacteria species of bacteriocin producing.%细菌素作为细菌合成的蛋白质(多肽)类抑菌物质,其广谱的抗菌活性,有望成为食品添加剂以及抗生素的替代品.主要对细菌素的分类及其作用机制、细菌素的生物合成及其调控,以及细菌素产生菌加以阐述.

  6. 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

  7. 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.

  8. Nisin ZP, a Bacteriocin and Food Preservative, Inhibits Head and Neck Cancer Tumorigenesis and Prolongs Survival.

    Science.gov (United States)

    Kamarajan, Pachiyappan; Hayami, Takayuki; Matte, Bibiana; Liu, Yang; Danciu, Theodora; Ramamoorthy, Ayyalusamy; Worden, Francis; Kapila, Sunil; Kapila, Yvonne

    2015-01-01

    The use of small antimicrobial peptides or bacteriocins, like nisin, to treat cancer is a new approach that holds great promise. Nisin exemplifies this new approach because it has been used safely in humans for many years as a food preservative, and recent laboratory studies support its anti-tumor potential in head and neck cancer. Previously, we showed that nisin (2.5%, low content) has antitumor potential in head and neck squamous cell carcinoma (HNSCC) in vitro and in vivo. The current studies explored a naturally occurring variant of nisin (nisin ZP; 95%, high content) for its antitumor effects in vitro and in vivo. Nisin ZP induced the greatest level of apoptosis in HNSCC cells compared to low content nisin. HNSCC cells treated with increasing concentrations of nisin ZP exhibited increasing levels of apoptosis and decreasing levels of cell proliferation, clonogenic capacity, and sphere formation. Nisin ZP induced apoptosis through a calpain-dependent pathway in HNSCC cells but not in human oral keratinocytes. Nisin ZP also induced apoptosis dose-dependently in human umbilical vein endothelial cells (HUVEC) with concomitant decreases in vascular sprout formation in vitro and reduced intratumoral microvessel density in vivo. Nisin ZP reduced tumorigenesis in vivo and long-term treatment with nisin ZP extended survival. In addition, nisin treated mice exhibited normal organ histology with no evidence of inflammation, fibrosis or necrosis. In summary, nisin ZP exhibits greater antitumor effects than low content nisin, and thus has the potential to serve as a novel therapeutic for HNSCC.

  9. 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

  10. 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

  11. 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

  12. TSST-1, enterotoxin and bacteriocin-like substance production by Staphylococcus aureus isolated from foods

    Directory of Open Access Journals (Sweden)

    S.A. Carvalho

    2013-10-01

    Full Text Available The production of Toxic Shock Syndrome Toxin-1 (TSST-1, enterotoxins and bacteriocin-like substances was evaluated in 95 strains of Staphylococcus aureus recovered from raw bovine milk (n=31 and from food samples involved in staphylococcal food poisoning (n=64. Enterotoxigenicity tests with the membrane over agar associated to optimal sensibility plate assays were performed and showed that 96.77% of strains recovered from milk and 95.31% from food samples produced enterotoxins A, B, C, D or TSST-1. Reference strains S. epidermidis, Bacillus cereus, Listeria monocytogenes, Lactobacillus casei, Pseudomonas aeruginosa, S. aureus, Salmonella Typhimurium, Escherichia coli, Enterococcus faecalis and Bacteroides fragilis were used as indicator bacteria in the antagonistic assays, the first five being sensitive to antagonistic substances. Brain heart infusion agar, in pH values ranging from 5.0 to 7.0 in aerobic atmosphere showed to be the optimum condition for antagonistic activity as evaluated with the best producer strains against the most sensitive indicator bacterium, L. monocytogenes. Sensitivity to enzymes confirmed the proteinaceous nature of these substances. Neither bacteriophage activity nor fatty acids were detected and the antagonistic activity was not due to residual chloroform. Results did not establish a positive correlation between the bacteriocinogenic profile and toxigenicity in the tested S. aureus strains.

  13. 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

  14. 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

  15. 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.

  16. 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

  17. 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...

  18. 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;

    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...... 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....

  19. 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)

  20. Nisin ZP, a Bacteriocin and Food Preservative, Inhibits Head and Neck Cancer Tumorigenesis and Prolongs Survival.

    Directory of Open Access Journals (Sweden)

    Pachiyappan Kamarajan

    Full Text Available The use of small antimicrobial peptides or bacteriocins, like nisin, to treat cancer is a new approach that holds great promise. Nisin exemplifies this new approach because it has been used safely in humans for many years as a food preservative, and recent laboratory studies support its anti-tumor potential in head and neck cancer. Previously, we showed that nisin (2.5%, low content has antitumor potential in head and neck squamous cell carcinoma (HNSCC in vitro and in vivo. The current studies explored a naturally occurring variant of nisin (nisin ZP; 95%, high content for its antitumor effects in vitro and in vivo. Nisin ZP induced the greatest level of apoptosis in HNSCC cells compared to low content nisin. HNSCC cells treated with increasing concentrations of nisin ZP exhibited increasing levels of apoptosis and decreasing levels of cell proliferation, clonogenic capacity, and sphere formation. Nisin ZP induced apoptosis through a calpain-dependent pathway in HNSCC cells but not in human oral keratinocytes. Nisin ZP also induced apoptosis dose-dependently in human umbilical vein endothelial cells (HUVEC with concomitant decreases in vascular sprout formation in vitro and reduced intratumoral microvessel density in vivo. Nisin ZP reduced tumorigenesis in vivo and long-term treatment with nisin ZP extended survival. In addition, nisin treated mice exhibited normal organ histology with no evidence of inflammation, fibrosis or necrosis. In summary, nisin ZP exhibits greater antitumor effects than low content nisin, and thus has the potential to serve as a novel therapeutic for HNSCC.

  1. Detection and characterization of a bacteriocin produced by Lactococcus lactis subsp. cremoris R isolated from radish.

    Science.gov (United States)

    Yildirim, Z; Johnson, M G

    1998-04-01

    Bacteria isolated from radish were identified as Lactococcus lactis subsp. cremoris R and their bacteriocin was designated lactococcin R. Lactococcin R was sensitive to some proteolytic enzymes (proteinase-K, pronase-E, proteases, pepsin, alpha-chymotrypsin) but was resistant to trypsin, papain, catalase, lysozyme and lipase, organic solvents, or heating at 90 degrees C for 15, 30 and 60 min, or 121 degrees C for 15 min. Lactococcin R remained active after storage at -20 and -70 degrees C for 3 months and after exposure to a pH of 2-9. The molecular weight of lactococcin R was about 2.5 kDa. Lactococcin R was active against many food-borne pathogenic and food spoilage bacteria such as Clostridium, Staphylococcus, Listeria, Bacillus, Micrococcus, Enterococcus, Lactobacillus, Leuconostoc, Streptococcus and Pediococcus spp., but was not active against any Gram-negative bacteria. Lactococcin R was produced during log phase and reached a maximum activity (1600 AU ml-1) at early stationary phase. The highest lactococcin R production was obtained in MRS broth with 0.5% glucose, at 6.5-7.0 initial pH values, 30 degrees C temperature and 18-24-h incubation times. Lactococcin R adsorbed maximally to its heat-killed producing cells at pH 6-7 (95%). Crude lactococcin R at 1280 AU ml-1 was bactericidal, reducing colony counts of Listeria monocytogenes by 99.98% in 3 h. Lactococcin R should be useful as a biopreservative to prevent growth of food-borne pathogenic and food spoilage bacteria in ready-to-eat, dairy, meat, poultry and other food products. Lactococcin R differs from nisin in having a lower molecular weight, 2.5 kDa vs 3.4 kDa, and in being sensitive to pepsin and alpha-chymotrypsin to which nisin is resistant. PMID:9633097

  2. Screening of bacteriocin producing lactic acid bacteria and the analysis of bacteriocin related genes%产细菌素乳酸菌的筛选及细菌素相关基因的分析

    Institute of Scientific and Technical Information of China (English)

    张旭; 赵斌; 张香美; 李平兰

    2013-01-01

    In order to obtain a bacteriocin producing strain,lactic acid bacteria were separated and screened with dissolve calcium circle and oxford cup double-plate method from premium fermentation meat.Morphological,physiological biochemistry method,16S rDNA and specific gene PCR amplification were used to identify the strain to species,and the bacteriocin related gene was analyzed to determine bacteriocin types.The results showed that,after eliminating organic acid,hydrogen peroxide and other interference factors,L-ZS9 still had antibacterial activity among the 92 strains and its antibacterial substances were sensitive to protease (acid protease,protease K,trypsin,pepsin,neutral protease),while insensitive to alpha amylase.Therefore,L-ZS9 was recognized as bacteriocin producing bacteria and identified as Lactobacillus paraplantarum.Further bacteriocin related gene PCR amplification showed that L-ZS9 contained Ⅱ b plantaricins EF,JK,Ⅱ c plantaricin A and plantaricin N encoding gene.The mature peptide sequences of plnF,plnK were identical with Lactobacillus plantarum C11 (X94434) and only one amino acid mutation occurred in pinE,plnJ mature peptide sequences.Therefore,the Lactobacillus paraplantarum L-ZS9 was a nature multibacteriocinogenic strain.%试验利用溶钙圈法及牛津杯双层平板法,从国内外优良发酵肉品中分离筛选产细菌素的乳酸菌,通过形态学、生理生化学鉴定,16S rDNA及种间特异性基因PCR扩增将菌株鉴定到种,并对其细菌素相关基因进行分析,初步确定细菌素种类.结果表明:在排除有机酸、过氧化氢等干扰因素后,从分离纯化到的92株乳酸菌中筛选到一株对指示菌仍有明显抑制作用的菌株L-ZS9,该菌株所产抑菌物质对蛋白酶(酸性蛋白酶、蛋白酶K、胰蛋白酶、胃蛋白酶和中性蛋白酶)敏感,而α-淀粉酶对其活性基本无影响,因而确定L-ZS9为细菌素产生菌.经鉴定L-ZS9为类植物乳杆菌,进一步对菌株细菌素

  3. 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

  4. 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

  5. The bacteriocins produced by Lactobacillus plantarum%植物乳杆菌细菌素的研究与应用

    Institute of Scientific and Technical Information of China (English)

    陈一然; 张明

    2011-01-01

    Because of the variety of bacteriocins from Lactobacillus plantarum and beneficial effects produced during ferment, it became popular to do research on bacteriocins from L plantarum. In this paper, with the purpose to provide a reference for further studies of bacteriocins from L plantarum, the characteristics were introduced elaborately, including types, molecule structures, inhibition mechanisms and inheritance control. Also, the applications of bacteriocins from L plantarum in food preservatives, medicine industry, and agriculture were simply summed up.%植物乳杆菌细菌素不仅种类多,产生菌在发酵过程中还可产生良好的保健功效,因此成为研究的热点.本文对植物乳杆菌细菌素的种类、分子结构、抑菌机制及遗传控制做了较为详尽的介绍,并简要介绍了植物乳杆菌细菌素在食品、医药、饲料中的应用,为进一步研究植物乳杆菌细菌素提供了参考.

  6. Molecular analysis of the bacteriocin-encoding plasmid pDGL1 from Enterococcus durans and genetic characterization of the durancin locus

    Science.gov (United States)

    Enterococci constitute a significant component of lactic acid bacteria normally present in the intestinal microflora and include strains that produce bacteriocins. The genetic determinants for durancin GL in Enterococcus durans 41D were identified on the 8,347 bp plasmid pDGL1 by plasmid curing exp...

  7. 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

  8. Pediocin PA-1, a Bacteriocin from Pediococcus acidilactici PAC1.0, Forms Hydrophilic Pores in the Cytoplasmic Membrane of Target Cells

    NARCIS (Netherlands)

    Chikindas, Michael L.; García-Garcerá, Maria J.; Driessen, Arnold J.M.; Ledeboer, Aat M.; Nissen-Meyer, Jon; Nes, Ingolf F.; Abee, Tjakko; Konings, Wilhelmus; Venema, Gerhardus

    1993-01-01

    Pediocin PA-1 is a bacteriocin which is produced by Pediococcus acidilactici PAC1.0. We demonstrate that pediocin PA-1 kills sensitive Pediococcus cells and acts on the cytoplasmic membrane. In contrast to its lack of impact on immune cells, pediocin PA-1 dissipates the transmembrane electrical pote

  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

    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...

  10. DNA Sequencing and Homologous Expression of a Small Peptide Conferring Immunity to Gassericin A, a Circular Bacteriocin Produced by Lactobacillus gasseri LA39

    NARCIS (Netherlands)

    Kawai, Yasushi; Kusnadi, Joni; Kemperman, Rober; Kok, Jan; Ito, Yoshiyuki; Endo, Mikiko; Arakawa, Kensuke; Uchida, Hideaki; Nishimura, Junko; Kitazawa, Haruki; Saito, Tadao

    2009-01-01

    Gassericin A, produced by Lactobacillus gasseri LA39, is a hydrophobic circular bacteriocin. The DNA region surrounding the gassericin A structural gene, gaaA, was sequenced, and seven open reading frames (ORFs) of 3.5 kbp (gaaBCADITE) were found with possible functions in gassericin A production, s

  11. 细菌素作为绿色饲料添加剂的潜在性思考%Potential consider of the bacteriocins as green feed additives

    Institute of Scientific and Technical Information of China (English)

    韩冰; 余占桥; 张日俊

    2011-01-01

    细菌素是由细菌的核糖体产生的一类蛋白质或多肽类物质.由于细菌素可以对一些病原菌产生抑菌或杀菌的作用,所以可以考虑将其作为饲料添加剂用于提高动物免疫力,调整动物胃肠道菌群微生态平衡.文中从细菌素药效和毒性等多方面阐述了其作为绿色饲料添加剂的前景,并提出了仍需解决的问题.%Bacteriocins are a kind of peptides or proteins synthetized in the ribosome of the bacteria.Part bacteriocins could inhibit or kill some pathogens, and are considered as feed additive, to improve the immunity of the animals and regulate the microflora of the intestinal tracts. The work mainly focused on the toxicology and pharmacology of bacteriocins to show the good prospect of bacteriocins as green feed additives.

  12. 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

  13. 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.

  14. 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

  15. Lacticin LC14, a new bacteriocin produced by Lactococcus lactis BMG6.14: isolation, purification and partial characterization.

    Science.gov (United States)

    Lasta, Samar; Ouzari, Hadda; Andreotti, Nicolas; Fajloun, Ziad; Mansuelle, Pascal; Boudabous, Abdellatif; Sampieri, Francois; Sabatier, Jean Marc

    2012-08-01

    A new bacteriocin, lacticin LC14, produced by Lactococcus lactis BMG6.14, was isolated and characterized. It was purified to homogeneity from overnight broth culture by ammonium sulfate precipitation, Sep-Pak chromatography, and two steps of reversed-phase HPLC. Lacticin LC14 showed bactericidal-type antimicrobial activity against several lactic acid bacteria and pathogenic strains including Listeria monocytogenes. It was inactivated by proteinase K and pronase E, but was resistant to papain, lysozyme, lipase and catalase. Lacticin LC14 was heat resistant, stable over a wide range of pH (2-10) and after treatment by solvents and detergents. Its N-terminal end was found unreactive towards Edman sequencing. Based on MALDI-TOF mass spectrometry, its molecular mass was 3333.7 Da. LC14 amino acid composition revealed a high proportion of hydrophobic residues, but no modified ones. LC14 may be able to challenge other well known other bacteriocins in probiotic and therapeutic applications.

  16. 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

  17. 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

  18. 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.

  19. 乳酸菌细菌素应用研究进展%Progress of Application Research on Lactic Acid Bacteria Bacteriocin

    Institute of Scientific and Technical Information of China (English)

    徐炳政; 王颖; 梁小月; 张东杰; 张桂芳

    2015-01-01

    The inhibitory metabolites from fermentation process of lactic acid bacteria included organic acid and bacteriocin,and bacteriocins from LAB have been concerned as the biological bacteriostat in recent years. This article briefly expounded the general classifications of bacteriocins from LAB,and focused on summarizing application progress of bacteriocins from LAB in the food industry,biological medicine industry and animal husbandry,and discussed its application safety and the existing problems in the present research. The bacteriocins from LAB as a kind of natural food preservative would be very broadly applied in the future.%乳酸菌发酵过程中的抑菌代谢产物包括有机酸和细菌素,乳酸菌细菌素作为一类生物抑菌剂近年来得到了广泛关注。文章简述了乳酸菌细菌素通用分类方式,着重综述了乳酸菌细菌素在食品工业、生物医药及畜牧养殖领域的应用进展,同时探讨了其应用安全性及目前研究中所存在的问题。相信不久的将来乳酸菌细菌素作为一类理想的天然食品防腐剂,应用前景将十分广阔。

  20. Bacteriocin production by strain Lactobacillus delbrueckii ssp. bulgaricus BB18 during continuous prefermentation of yogurt starter culture and subsequent batch coagulation of milk.

    Science.gov (United States)

    Simova, E D; Beshkova, D M; Angelov, M P; Dimitrov, Zh P

    2008-06-01

    By screening for bacteriocin-producing lactic acid bacteria of 1,428 strains isolated from authentic Bulgarian dairy products, Lb. bulgaricus BB18 strain obtained from kefir grain was selected. Out of 11 yogurt starters containing Lb. bulgaricus BB18 and S. thermophilus strains resistant to bacteriocin secreted by Lb. bulgaricus BB18 a yogurt culture (S. thermophilus 11A+Lb. bulgaricus BB18) with high growth and bacteriocinogenic activity in milk was selected. Continuous (pH-stat 5.7) prefermentation processes were carried out in milk at 37 degrees C in a 2l MBR bioreactor (MBR AG, Zurich, Switzerland) with an IMCS controller for agitation speed, temperature, dissolved oxygen, CO2 and pH. Prefermented milk with pH 5.7 coagulated in a thermostat at 37 degrees C until pH 4.8-4.9. S. thermophilus 11A and Lb. bulgaricus BB18 grew independently in a continuous mode at similar and sufficiently high-dilution rates (D=1.83 h(-1)-S. thermophilus 11A; D=1.80 h(-1)-Lb. bulgaricus BB18). The yogurt cultures developed in a stream at a high-dilution rate (D=2.03-2.28 h(-1)). The progress of both processes (growth and bacteriocin production) depended on the initial ratio between the two microorganisms. The continuous prefermentation process promoted conditions for efficient fermentation and bacteriocinogenesis of the starter culture during the batch process: strong reduction of the times for bacteriocin production and coagulation of milk (to 4.5-5.0 h); high cell productivity (lactobacilli-4x10(12) CFU ml(-1), streptococci-6x10(12) CFU ml(-1)); high productivity of bacteriocins (4,500 BU ml(-1))-1.7 times higher than the bacteriocinogenic activity of the batch starter culture.

  1. Purification of the Bacteriocin Isolated from Lactobacillus acidophilus and Effect of Surfactant on the Antibacterial Activity of Bacteriocin%嗜酸乳杆菌细菌素的分离纯化及表面活性剂对其活性的影响1)

    Institute of Scientific and Technical Information of China (English)

    张帅; 王金凤; 马永强

    2012-01-01

      从本研究室保藏的一株来自于凯菲尔粒的嗜酸乳杆菌培养基质中分离出具有抑菌活性的蛋白组分———细菌素,对该嗜酸乳杆菌所产生的细菌素的分离方法及表面活性剂对其抑菌活性的影响作用进行了研究。结果表明,嗜酸乳杆菌在添加了油酸的 MRS 培养基中培养16h 后达到产细菌素高峰;对细菌素分离纯化研究包括三个步骤:硫酸铵沉淀、离子交换色谱(IEC)和疏水作用色谱(HIC)。不同类型的表面活性剂对细菌素的抑菌活性具有不同的影响。%  Bacteriocin which is a kind of protein with antibacterial activity is produced from L actobacillus acidophilus ,and the strain is isolated from kefir grain preserved in the lab .The separation method about bacteriocin and the influence of the different surfactants on the antibacterial activity of bacteriocin is stud -ied .The results show that L actobacillus acidophilus is cultured in MRS medium addind oleic acid after 16h culture ,a peak of the bacteriocin-producing is reached .And The purification method about bacterio-cin includes three operations ,which separately are ammonium sulfate precipitation ,ion exchange chroma-tography(IEC)and Hydrophobic Interaction Chromatography . The different kinds of surfactants may have the different effects on the antibacterial activity of bacteriocin .

  2. 细菌素及其在动物生产中的应用%Bacteriocins and Their Application in Animal Production

    Institute of Scientific and Technical Information of China (English)

    朱双; 张爱忠; 姜宁; 任文; 蔡鹏; 王法明; 穆洋; 王立学; 张欣鑫

    2014-01-01

    Due to the emergence of antibiotic-resistant pathogens, some infectious diseases are difficult to treat and are getting worse.In recent years, the development of new and effective antibiotics is slow.However, the alternative antibiotics bacteria are concerned in recent years, which have a great potential to inhibit antibiotic-resistant pathogens by bacteriocins.Bacteriocins are small antimicrobial peptides ( AMPS) which are produced by many bacteria, they not only can inhibit effectively pathogen growth, but also can play an important role in health care as probiotics.At the same time, bacteriocins have been commonly used as a preservative in food production.With the focus on health and safety of livestock products as well as popularization and application of probiotics in diet increasing, bacteriocins will be widely used in animal production.This review summarizes the concept, classification, mechanism of bacteriocins, and discusses present research progress about the appli-cation of bacteriocins in animal production.%由于抗生素耐药病原菌的出现,一些传染性疾病已难以治疗并且日益恶化。近年来开发新的和有效的抗生素进展缓慢。然而,可替代抗生素的细菌素近些年来备受关注,其在控制抗生素耐药病原菌上拥有巨大的潜力。细菌素是由许多细菌产生的小抗菌肽( AMPs),不仅可以有效地抑制病原体生长,还可以作为益生菌在医疗中发挥重要作用。同时,细菌素作为防腐剂在食品生产中普遍应用,随着人们对畜产品卫生与安全的关注以及益生菌在饲料中的推广应用,细菌素在动物生产中也有着非常广阔的应用前景。为此,本文旨在在介绍细菌素的概念、分类、作用机制的基础上,进一步介绍细菌素在动物生产上的应用。

  3. The application of bacteriocin in feed%细菌素在饲料中的应用

    Institute of Scientific and Technical Information of China (English)

    饶正华; 李丽蓓; 高生

    2001-01-01

    @@ 细菌素(Bacteriocin)由于其种类多、无毒、大部分基因位于质粒上、分子量小、含修饰氨基酸、结构复杂等特点,被认为是分子遗传、基因工程、蛋白质工程、食品添加剂、化妆品、皮肤保健、抑制病原菌和调节肠道菌群的好材料.随着饲料中益生菌的推广使用和人们对饲料卫生的重视,细菌素在饲料中将会得到广泛的应用.

  4. 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

  5. Gene Design of Bacteriocin E50-52 and Construction of its Pichia pastoris Expression Vector%细菌素Bacteriocin E50-52(H)基因设计及其毕赤酵母表达载体构建

    Institute of Scientific and Technical Information of China (English)

    余占桥; 马青山; 韩冰; 张日俊

    2011-01-01

    设计及合成细菌素Bacteriocin E50-52(H)基因,克隆到组成型分泌表达质粒pGAPZαA中构建重组质粒pGAPZα-Bacteriocin E(H),经PCR、测序验证正确后,电转化整合到毕赤酵母基因组,基因组PCR、测序验证结果表明成功构建了细菌素组成型重组表达载体,为在毕赤酵母中表达奠定了基础.%Bacteriocin E50-52 gene was designed according to its amino acid sequence and cloning site of constitutive secreted plasmid pGAPZαA,then synthesized,inserted into pMD18-T. Recombinant pGAPZα- Bacteriocin E was constructed by ligating the digested target gene and pGAPZαA with Xho Ⅰ and Xba Ⅰ. Recombinant Pichia pastoris was constructed by transforming linearized recombinant plasmid in strain SMD1168. Sequencing result of recombinant vector and genome of Pichia pastoris indicated this expression plasmid was successfully constructed.

  6. 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.

  7. 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...

  8. 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...

  9. Optimization of growth and bacteriocin activity of the food bioprotective Carnobacterium divergens V41 in an animal origin protein free medium

    Directory of Open Access Journals (Sweden)

    Anne BRILLET-VIEL

    2016-08-01

    Full Text Available Optimization of Carnobacterium divergens V41 growth and bacteriocin activity in a culture medium deprived of animal protein, needs for food bioprotection, was performed by using a statistical approach. In a screening experiment, twelve factors (pH, temperature, carbohydrates, NaCl, yeast extract, soy peptone, sodium acetate, ammonium citrate, magnesium sulphate, manganese sulphate, ascorbic acid and thiamine were tested for their influence on the maximal growth and bacteriocin activity using a two-level incomplete factorial design with 192 experiments performed in microtiter plate wells. Based on results, a basic medium was developed and three variables (pH, temperature and carbohydrates concentration were selected for a scale-up study in bioreactor. A 23 complete factorial design was performed, allowing the estimation of linear effects of factors and all the first order interactions. The best conditions for the cell production were obtained with a temperature of 15°C and a carbohydrates concentration of 20 g/l whatever the pH (in the range 6.5-8, and the best conditions for bacteriocin activity were obtained at 15°C and pH 6.5 whatever the carbohydrates concentration (in the range 2-20 g/l. The predicted final count of C. divergens V41 and the bacteriocin activity under the optimized conditions (15°C, pH 6.5, 20 g/l carbohydrates were 2.4 x 1010 CFU/ml and 819200 AU/ml respectively. C. divergens V41 cells cultivated in the optimized conditions were able to grow in cold-smoked salmon and totally inhibited the growth of Listeria monocytogenes (< 50 CFU g-1 during five weeks of vacuum storage at 4° and 8°C.

  10. 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

  11. 乳酸菌细菌素纯化技术的检测及研究进展%Detection technique of bacteriocin from lactic acid bacteria and research advance in separation and purification technology

    Institute of Scientific and Technical Information of China (English)

    刘文丽; 张兰威; John shi; 易华西

    2012-01-01

    细菌素可以抑制大量的食品源腐败菌和致病菌,因此,近年来受到国内外广大学者的关注,其中乳酸菌细菌素因其安全性尤为受到关注。然而要使细菌素更好地应用到生物技术领域,揭示乳酸菌细菌素的生物化学结构和作用位点就显得尤为重要,而这又是建立在乳酸菌细菌素的纯化基础上。文章结合乳酸菌细菌素纯化技术及检测的最新研究进展,讨论乳酸菌细菌素在食品和医疗领域的发展潜力。%Bacteriocins can be against numerous foodborne pathogen and spoilage organisms,hence researchers at home and aboard are interested in bacteriocins,especially,bacteriocin from lactic acid bacteria(LAB) are focused most.However,for bacteriocin could be applied to biotechnological fields better,it is essential to illuminate its biochemical structure and its mode of action,which needs that bacteriocins is purified to homogeneity.The main technologies used for the purification and detection of numerous bacteriocins was described,the exploration of bacteriocins potential in LAB was also discussed.

  12. Current advances and prospects of researches on the bacteriocins produced by Lactobacillus sakei%清酒乳杆菌细菌素研究的现状及展望

    Institute of Scientific and Technical Information of China (English)

    姜洁; 施波; 方佳琪; 陈晓琳; 祁克宗; 张明

    2011-01-01

    In addition to using the strains of Lactobacillus sakei as the starter cultures to develop the flavor and quality of sausage, most of the bacteriocins from L. sakei have strong inhibitory effects on pathogenic Listeria monocytogenes.There are various bacteriocins produced by L. sakei, and these bacteriocins have different properties. In this paper, the types of bacteriocins from L. sakei, the effect of meat products storage conditions ( or meat production condition) on the stability of L. sakei and bacteriocins, as well as application of bacteriocins from L. sakei as the food preservation were reviewed. This review is aimed at providing a reference for discovering new bacteriocins from L. sakei.%清酒乳杆菌不仅可作为发酵香肠的发酵剂赋予香肠良好的风味和品质,而且绝大多数清酒乳杆菌细菌素对食源性致病菌单核增生李斯特菌具有较强的抑制作用.清酒乳杆菌细菌素种类多,性质各异.本文分别从清酒乳杆菌细菌素的种类,肉制品环境对清酒乳杆菌和细菌素稳定性的影响以及清酒乳杆菌细菌素在食品中的应用研究进行了概述,为寻找新的具有良好性能的清酒乳杆菌细菌素提供了参考.

  13. Heterologous expression and purification of plantaricin NC8, a two-peptide bacteriocin against Salmonella spp. from Lactobacillus plantarum ZJ316.

    Science.gov (United States)

    Jiang, Han; Li, Ping; Gu, Qing

    2016-11-01

    Bacteriocin, which is produced by lactic acid bacteria (LAB), has the potential to act as natural preservatives in the food industry. To develop strategies to overproduce such peptides, plantaricin NC8, a class IIb LAB bacteriocin that consists of two peptides, PLNC8α and PLNC8β, was successfully heterologously expressed in Escherichia coli BL21 (DE3). PLNC8α and PLNC8β peptides were expressed as His6-tag fusion proteins and were separated by Ni(2+) chelating affinity chromatography. To get the PLNC8α and PLNC8β peptides without extra amino acids in the N-terminus, the fusion proteins were cleaved by enterokinase and further purified using the Ni-NTA Sefinose™ Resin Kit. The molecular masses of peptides were checked using Tricine-SDS-PAGE and MALDI-TOF-MS. The yield of purified PLNC8α was around 2-2.5 mg/L, and the yield of PLNC8β was around 1.5-2 mg/L. The antimicrobial spectrum of cleaved peptides was detected and the synergistic action of PLNC8α and PLNC8β was preliminarily confirmed. It was found that E. coli was a suitable host for heterologous expression of plantaricin NC8 with a significant yield. Importantly, the bacteriocin appeared to be very active for controlling and inhibiting the food-borne pathogenic Gram-negative bacteria Salmonella spp., and might be useful as a natural preservative candidate. PMID:27373940

  14. 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

  15. 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.

  16. A sequential statistical approach towards an optimized production of a broad spectrum bacteriocin substance from a soil bacterium Bacillus sp. YAS 1 strain.

    Science.gov (United States)

    Embaby, Amira M; Heshmat, Yasmin; Hussein, Ahmed; Marey, Heba S

    2014-01-01

    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.

  17. 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.

  18. 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.

  19. 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

    Science.gov (United States)

    Jiménez, Juan J.; Gútiez, Loreto; Cintas, Luis M.; Herranz, Carmen; Hernández, Pablo E.

    2015-01-01

    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. PMID:25821820

  20. 嗜酸乳杆菌产细菌素的分离纯化研究%SEPARATION AND PURIFICATION OF BACTERIOCINS PRODUCED BY LACTOBACILLUS ACIDOPHILUS

    Institute of Scientific and Technical Information of China (English)

    陈静; 何连芳; 张玉苍

    2011-01-01

    We carried out the separation and purification of bacteriocins produced by Lactobacillus acidophlus and studied the biological characteristics. The results showed that the bacteriocins produced by Lactobacillus acidophlus had thermal stability and better stability in the pH range of 2.0 to 9.0, and still kept the activity after being processed at 120 ℃ for 30 min. The fermented supernant was sensitive to proteases, which showed that the antibacterial substance belonged to proteins; and the fermented supernant had inhibitory effects on Gram-positive bacteria and Gram-negative bacteria. We could prepare the crude bacteriocin extract after ammonium sulfate precipitation and dialysis of the fermented supernant, then purified the crude bacteriocin extract by SephadexG-50 gel chromatography, and determined that the molecular weight of the bacteriocins was about 2 000 by Tricine-SDS-PAGE.%对一株嗜酸乳杆菌所产细菌素进行了分离纯化,并研究了其生物学特性.结果表明,嗜酸乳杆菌产的细菌素具有热稳定性,在120 ℃处理30 min仍保留活性,该细菌素在pH2.0 ~9.0范围内有较好的稳定性.发酵上清液对蛋白酶敏感,表明此抑茼物质为蛋白类物质,对革兰氏阴性菌及革兰氏阳性菌均有抑制作用.发酵上清液经过硫酸铵沉淀、透析后得到细菌素粗提液,然后利用SephadexG-50凝胶层析进行纯化,采用Tricine-SDS-PAGE电泳测其相对分子质量约为2 000.

  1. Use of the Yeast Pichia pastoris as an Expression Host for Secretion of Enterocin L50, a Leaderless Two-Peptide (L50A and L50B) Bacteriocin from Enterococcus faecium L50▿

    Science.gov (United States)

    Basanta, Antonio; Gómez-Sala, Beatriz; Sánchez, Jorge; Diep, Dzung B.; Herranz, Carmen; Hernández, Pablo E.; Cintas, Luis M.

    2010-01-01

    In this work, we report the expression and secretion of the leaderless two-peptide (EntL50A and EntL50B) bacteriocin enterocin L50 from Enterococcus faecium L50 by the methylotrophic yeast Pichia pastoris X-33. The bacteriocin structural genes entL50A and entL50B were fused to the Saccharomyces cerevisiae gene region encoding the mating pheromone α-factor 1 secretion signal (MFα1s) and cloned, separately and together (entL50AB), into the P. pastoris expression and secretion vector pPICZαA, which contains the methanol-inducible alcohol oxidase promoter (PAOX1) to express the fusion genes. After transfer into the yeast, the recombinant plasmids were integrated into the genome, resulting in three bacteriocinogenic yeast strains able to produce and secrete the individual bacteriocin peptides EntL50A and EntL50B separately and together. The secretion was efficiently directed by MFα1s through the Sec system, and the precursor peptides were found to be correctly processed to form mature and active bacteriocin peptides. The present work describes for the first time the heterologous expression and secretion of a two-peptide non-pediocin-like bacteriocin by a yeast. PMID:20348300

  2. 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

  3. Isolation and Taxonomic Identity of Bacteriocin-Producing Lactic Acid Bacteria from Retail Foods and Animal Sources.

    Science.gov (United States)

    Henning, Chris; Vijayakumar, Paul; Adhikari, Raj; Jagannathan, Badrinath; Gautam, Dhiraj; Muriana, Peter M

    2015-03-19

    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.

  4. 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

  5. Potential probiotics from Indian major carp, Cirrhinus mrigala. Characterization, pathogen inhibitory activity, partial characterization of bacteriocin and production of exoenzymes.

    Science.gov (United States)

    Mukherjee, Anjan; Dutta, Dipanjan; Banerjee, Sudeshna; Ringø, Einar; Breines, Eva Marie; Hareide, Ellinor; Chandra, Goutam; Ghosh, Koushik

    2016-10-01

    The study explored antagonistic activity of the cellular components of potential probiotic bacteria from mrigal (Cirrhinus mrigala) against fish pathogens with a basic insight of the chemical nature of the antagonistic compound. Totally 208 autochthonous gut bacteria were isolated, of which 22 strains revealed antagonism towards ≥2 of the six common fish pathogens. Zones of inhibition (halo diameter) were presented as score and the four most promising strains were selected as putative probiotics based on the cumulative score assigned. Further, evaluation of different cellular components exhibited bactericidal activity against the fish pathogens. Verification of other probiotic properties revealed that each of the selected strains produced diverse extra-cellular enzymes. The selected strains grew better in intestinal mucus than skin mucus, were resistant to diluted bile juice (2-20%) and safe for the target fish. The extracellular product used as crude bacteriocin revealed thermostability (up to 90°C) and activity over wide pH range (4-9). Partial loss of activity through treatment with proteinase-K and trypsin indicated proteinaceous nature of the antibacterial compound produced by the probiotic strains. 16S rRNA partial gene sequencing revealed that the four strains CM1FG7, CM1HG5, CM3FG19 and CM3HG10 were similar to Bacillus stratosphericus (KM277362), Bacillus aerophilus (KM277363), Bacillus licheniformis (KM277364) and Solibacillus silvestris (KM277365), respectively. PMID:27663374

  6. Efficacy of organic acids, bacteriocins, and the lactoperoxidase system in inhibiting the growth of Cronobacter spp. in rehydrated infant formula.

    Science.gov (United States)

    Oshima, Satoru; Rea, Mary C; Lothe, Sheba; Morgan, Sheila; Begley, Maire; O'Connor, Paula M; Fitzsimmons, Aidan; Kamikado, Hideaki; Walton, Richard; Ross, R Paul; Hill, Colin

    2012-10-01

    Thirty-three antimicrobial agents, including antimicrobial peptides (nisin, lacticin 3147, isracidin), organic acids, emulsifiers (organic acid esters), glycine, lysozyme, tocopherol, EDTA, milk fat globule membrane, and the lactoperoxidase system (LPOS) were screened for anti-Cronobacter sakazakii activity. The compounds were initially screened individually in parallel in synthetic media. Those showing antimicrobial activity were then tested in reconstituted whole milk and finally in reconstituted powdered infant formula (PIF), using mild temperatures of reconstitution and prolonged storage at room temperature. Propionic acid and monocaprylin (as POEM M-100) in combination showed inhibitory activity at sufficiently low concentrations (0.1 to 0.2%) in milk to be considered as potential antimicrobial additives for the inhibition of C. sakazakii in reconstituted PIF. More interestingly, LPOS, when combined with the broad-spectrum bacteriocins nisin or lacticin 3147, inhibited outgrowth of C. sakazakii at 37°C for 8 h. The combined effects of POEM M-100 and either acetate or propionate and LPOS with lacticin 3147 or nisin were evaluated under the Food and Agriculture Organization of the United Nations-World Health Organization high-risk scenario for PIF, i.e., low temperature of reconstitution and long storage or feeding times at ambient temperature. In the presence of LPOS and lacticin 3147, growth of Cronobacter spp. was inhibited for up to 12 h when the PIF was rehydrated at 40 or 50°C. These results highlight the potential of combinatory approaches to improving the safety of infant milk formula.

  7. Sequence-specific {sup 1}H assignment and secondary structure of the bacteriocin AS-48 cyclic peptide

    Energy Technology Data Exchange (ETDEWEB)

    Langdon, G.M.; Bruix, M. [Instituto de Estructura de la Materia, C.S.I.C. (Spain); Galvez, A.; Valdivia, E.; Maqueda, M. [Universidad de Granada, Departamento de Microbiologia, Facultad de Ciencias (Spain); Rico, M. [Instituto de Estructura de la Materia, C.S.I.C. (Spain)

    1998-07-15

    The bacteriocin AS-48 is a cationic peptide (7149 Da) having a broad antimicrobial spectrum, encoded by the 68 kb conjugative plasmid pMB2 from Enterococcus faecalis S-48. It is a unique peptide since it has a cyclic structure, which is achieved by the formation of a tail-head peptide bond after ribosomal synthesis (Galvez et al., 1989; Martinez-Bueno et al., 1994; Samyn et al., 1994). Preliminary CD and calorimetric studies (data not shown) pointed towards a highly helical and very stable three dimensional structure.All the information gathered until now indicates that the target of AS-48 is the cytoplasmic membrane in which it opens channels or pores, leading to dissipation of the proton motive force and cell death, which in some cases is also followed by bacterial lysis (Galvez et al., 1991). This peptide is a suitable tool for studying protein-membrane interactions, and it also offers promising perspectives for biotechnological applications.Knowledge of the 3D structure of AS-48 is a first step in the conduct of further structure-function studies. Here we report the complete{sup 1} H NMR assignment of its proton resonances together with the resulting secondary structure pattern as prerequisites for the determination of a high-resolution 3D solution structure.

  8. 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

  9. Histopathological studies on the effect of bacteriocin producing Bacillus cereus isolate from ‘wara’ a local soft cheese on the liver, kidney and reproductive organs of Wistar albino rats

    Directory of Open Access Journals (Sweden)

    Anyanwu, C.

    2013-01-01

    Full Text Available Aims: This study was done to generate a baseline data on the effect of Bacillus cereus and its bacteriocin on the liver, kidney and reproductive organs in both sexes at different concentration.Methodology and results: B. cereus and its bacteriocin were injected intramuscularly in male and female Wistar rats at doses equivalent to 102 CFU and 104 CFU dilutions. Body weights were also noted. The liver, kidney and reproductive organs of the animals were examined for histopathological changes. The liver of female rats administered B. cereus at 102 CFU showed portal and cellular infiltration by mononuclear cells, diffuse hydropic degeneration and severe interstitial hemorrhages of the kidney was observed when 104 CFU of B. cereus was given. Male rats administered 102 CFU and 104 CFU of B. cereus showed diffuse hydropic degeneration and portal congestion of the liver while at 104 CFU the kidney showed diffuse, moderate interstitial cellular infiltration. This is more evident in the wistar rats administered with bacilli organism than the groups that received the bacteriocin. The reproductive organs of treated animals showed no pathological lesions. There were no visible tissue pathological changes in the untreated groups. There were no visible tissue pathological changes in the untreated groups.Conclusion, significance and impact study: The absence of observable toxic effects of the bacteriocin of B. cereus on the sex organs, is not sufficient to determine the safety of this bacteriocin since pathological lesions were observed in the liver and kidney. We hereby suggest a further study on characterization and purification of this bacteriocin as a biopreservative in items not meant for human use or consumption.

  10. Regulation of Bacteriocin Synthesis by Quorum Sensing in Lactic Acid Bacteria:A Review%群体感应系统在乳酸菌产细菌素中的作用

    Institute of Scientific and Technical Information of China (English)

    满丽莉; 孟祥晨; 王辉; 赵日红

    2011-01-01

    Several lactic acid bacteria(LAB) produce peptides with antimicrobial activity usually referred to as bacteriocins.Bacteriocins are diverse in terms of structure,mode of action,antimicrobial spectrum,and potency.Both LAB and their bacteriocins are generally regarded as safe.Bacteriocins produced by LABs have demonstrated great potential as natural preservatives Intercellular communication has emerged as the key regulatory mechanism that controls the synthesis of bacteriocins via a regulatory strategy denominated quorum sensing,which allows population-wide synchronised production of antimicrobial peptides as a function of cell density.The intercellular communication phenomenon required for sensing of the cell density is mediated by secreted signaling molecules that accumulate in the environment as the cell density increase and activate signal transduction cascades,resulting in the production of bacteriocins.This review aims at describing the types of signal molecules,signal transduction mechanism and the regulation of quorum sensing in bacteriocins synthesis of LAB and understanding the regulation mechanism of quorum sensing involved in the production of two classes of bacteriocin in LAB.%许多乳酸菌能够产生抗菌活性肽——细菌素,细菌素具有不同的结构、作用方式、抑菌谱和效价,通常认为乳酸菌和其所产的细菌素都是安全的,乳酸菌所产细菌素作为天然食品防腐剂已显示了巨大的潜能。基于群体感应的细胞间交流已成为细菌素合成的关键调控机制,群体感应作为细胞密度函数,可使细菌素产生保持同步性。群体感应需通过信号分子介导感知菌体密度,信号分子随着菌体密度增加而增加,并激活信号转导级联使菌体产生细菌素。本文通过对乳酸菌群体感应信号分子种类、信号转导机制及群体感应系统对两类细菌素合成的调控进行综述,以初步了解群体感

  11. 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

  12. 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

  13. 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...

  14. 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...

  15. 枯草芽孢杆菌3-2产细菌素发酵条件的优化%Optimization of Fermentation Condition in Bacteriocin Produced by Prunella Bacillus 3-2

    Institute of Scientific and Technical Information of China (English)

    杨宇清; 郑一敏; 胡杨; 乐亮; 江娟; 王宁; 林海珠

    2011-01-01

    To obtain optimal fermentation conditions of bacteriocin produced by prunella bacillus 3-2,the medial components and cultural conditions for producing bacteriocin of prunella bacillus 3-2 were optimized by single factor test in shake-flask.Results showed that BPY was suitable for producing bacteriocin.The optimum culture conditions were fermented 24h,at temperature 35℃ with starting pH at 7.0,medium volume 100ml in 500ml flask,inoculum volume 3% and seed aged were 12h.Conclusion is that it improves the bacteriocin production by optimal fermentation conditions.%采用单因素法,通过摇瓶培养,对枯草芽孢杆菌3-2产细菌素的发酵培养基和发酵条件进行优化。结果表明:产细菌素的最佳培养基是BPY培养基,最适合发酵时间为24 h,最适发酵温度为35℃,最适起始pH值为7.0,最适装液量为100 mL/500 mL,最适接种量为3%,最适接种龄为12 h。通过优化发酵条件可提高细菌素的产量。

  16. 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.

  17. 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

  18. 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.

  19. 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.

  20. Study and application of bacteriocin against bacterial resistance%细菌素的抗细菌耐药研究及应用现状

    Institute of Scientific and Technical Information of China (English)

    章昱(综述); 周云芳(审校)

    2015-01-01

    With the advent of antibiotics such as penicillin, the mortality from bacterial infection has been greatly reduced. But decades later, after widespread application of antibiotics, we should deal with the severe situation that the antibiotic re-sistance is becoming increasingly serious, the infections from resistant strains are difficult to control and development of new antibiotics is rather slow.In order to overcome these problems, researchers are exploring new ways besides antibiotics, and pay more attentions to bacteriocins because of their antibacterial activities.But the applications of bacteriocins are also re-stricted by antibacterial spectrum, production and so on, and making a breakthrough becomes a hotspot.This review will focus on the status, application and heterologous expression of bacteriocins.%随着青霉素等抗生素的问世,人类因细菌感染所致疾病的死亡率大为降低;但在抗生素广泛应用至今,我们又面临着细菌耐药日趋严重、耐药菌感染难以控制、新抗生素研发脚步迟滞的严峻局势。如何应对这一全球性的难题,研究者们殚精竭虑,力求在抗生素以外寻求新的突破,有着比抗生素更悠久历史、同样具有抗菌活性的细菌素引起了研究者们的重视。但抗菌谱、产量等问题使细菌素的应用受到了限制,打破瓶颈成了当下研究的热点。本文主要对细菌素的研究现状、应用及异源表达做了相关综述。

  1. 产细菌素乳酸菌的鉴定及其特性研究%Identification of Bacteriocin-Producing Lactobacillus and Study on Its Characteristic

    Institute of Scientific and Technical Information of China (English)

    王小娜; 宋达峰; 顾青

    2011-01-01

    Lactic acid bacteria isolated in the laboratory was identified. After eliminating some interference factors such as the organic acids, hydrogen peioxides and so on, the bacteriocin obtained from culture supernatant still remained active, and significant reduction in antimicrobial activity was observed after treatment with proteinase K and trypsin, confirming its proteinaceous nature. The bacteriocin showed high temperature stability up to 120 ℃ for 30 min with less loss in its activity, and had pH stability in the range of 2~4. The molecular weight of the bacteriocin is approximately 4.0 kDa by tricine-SDS-PAGE assay. And the bacteriocin also evidenced a broad spectrum of antibacterial activity against both Gram-negative and Gram-positive bacteria including Listeria monocytogenes, Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Salmonella enterica, Pseudomonas aeruginosa, Shigella flexneri. Lactobacillus plantarum on the base of physiological and biochemical characteristics and 16S rRNA gene sequences, named as Lactobacillus plantarum ZJ317.%从婴儿粪便中分离获得能够产生抑菌活性物质的乳酸菌,通过排除有机酸、过氧化氢的干扰试验,该菌发酵上清液仍有明显的抑菌活性;通过蛋白酶K和胰蛋白酶试验,证明该菌株产生的抑菌活性物质具有蛋白质性质,是一种细菌素.初步提纯该细菌素,其抑菌活性较适pH范围为2~4,120℃热处理30 min后仍有70%的抑菌活性.经Trcine-SDS-PAGE试验分析该细菌素分子质量为4kDa.抑菌谱测定结果表明,该细菌素不仅对革兰氏阳性菌(单增李斯特氏菌、枯草芽孢杆菌、金黄色葡萄球菌等)有抑制作用,而且还抑制革兰氏阴性菌(大肠杆菌、沙门氏菌、恶臭假单胞菌、福氏志贺氏菌等),具有广谱的抑菌作用.通过菌落形态、生理生化特性试验和16S rRNA基因序列分析,鉴定该乳酸菌为植物乳杆菌,命名为Lactobacillus plantarum ZJ317.

  2. Chemical synthesis and characterization of J46 peptide, an atypical class IIa bacteriocin from Lactococcus lactis subsp. cremoris J46 Strain.

    Science.gov (United States)

    Lasta, Samar; Fajloun, Ziad; Darbon, Hervé; Mansuelle, Pascal; Andreotti, Nicolas; Sabatier, Jean-Marc; Boudabous, Abdellatif; Sampieri, François

    2008-02-01

    Bacteriocin J46 is a 27-residue polypeptide produced by Lactococcus lactis subsp. cremoris J46 in fermented milk. The natural form of J46 (nJ46) exhibits a broad antimicrobial spectrum. Herein, we produced the synthetic form of J46 (sJ46) by solid-phase chemical synthesis. The biochemical and physico-chemical properties of sJ46, as well as its antimicrobial activity, were found to be identical to those of its natural counterpart nJ46. It showed a potent antimicrobial activity against both lactic acid bacteria and other Gram-positive microorganisms. (1)H-NMR conformational analysis of sJ46 indicates that it adopts a flexible random coil structure.

  3. 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。

  4. 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

  5. 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.

  6. Three distinct two-component systems are involved in resistance to the class I bacteriocins, Nukacin ISK-1 and nisin A, in Staphylococcus aureus.

    Directory of Open Access Journals (Sweden)

    Miki Kawada-Matsuo

    Full Text Available Staphylococcus aureus uses two-component systems (TCSs to adapt to stressful environmental conditions. To colonize a host, S. aureus must resist bacteriocins produced by commensal bacteria. In a comprehensive analysis using individual TCS inactivation mutants, the inactivation of two TCSs, graRS and braRS, significantly increased the susceptibility to the class I bacteriocins, nukacin ISK-1 and nisin A, and inactivation of vraSR slightly increased the susceptibility to nukacin ISK-1. In addition, two ABC transporters (BraAB and VraDE regulated by BraRS and one transporter (VraFG regulated by GraRS were associated with resistance to nukacin ISK-1 and nisin A. We investigated the role of these three TCSs of S. aureus in co-culture with S. warneri, which produces nukacin ISK-1, and Lactococcus lactis, which produces nisin A. When co-cultured with S. warneri or L. lactis, the braRS mutant showed a significant decrease in its population compared with the wild-type, whereas the graRS and vraSR mutants showed slight decreases. Expression of vraDE was elevated significantly in S. aureus co-cultured with nisin A/nukacin ISK-1-producing strains. These results suggest that three distinct TCSs are involved in the resistance to nisin A and nukacin ISK-1. Additionally, braRS and its related transporters played a central role in S. aureus survival in co-culture with the strains producing nisin A and nukacin ISK-1.

  7. New Antifungal Bacteriocin-Synthesizing Strains of Lactococcus lactis ssp. lactis as the Perspective Biopreservatives for Protection of Raw Smoked Sausages

    Directory of Open Access Journals (Sweden)

    L. G. Stoyanova

    2010-01-01

    Full Text Available Problem statement: Screening for the effective bacteriocin-synthesizing strains of Lactococcus lactis as the perspective biopreservatives was performed. We used a raw milk and dairy products from different climatic regions as well as from powerful drinks of mixed lactic acid and alcoholic fermentation: kurunga, kumiss and Iranian Dough, that were widely used by local population to prevent diseases. Approach: The special interest was paid to isolates of lactococci with antagonistic activity. According to their morphological, cultural, physiological, biochemical properties and sequence of 16S rRNA gene they were identified as Lactococcus lactis ssp. lactis. Only nine from the selected 94 strains expressed a broad spectrum of activity against Gram-positive and Gramnegative bacteria including pathogens (Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Proteus vulgaris, Salmonella gallinarum, moulds (Aspergillus, Fusarium, Penicillium genera, as well as yeasts (Rhodotorula, Candida. Results: It reveals the unique biological properties for isolated natural strains of Lactococcus lactis species. Most effective new bacteriocin-synthesizing strains 194 and K-205 were isolated from raw cow milk and kurunga from Buryatia. These strains had high antibiotic activity up to 3600 and 2700 IU mL-1 as compared to nisin and up to 2500-1700 IU mL-1 as compared to fungicidal antibiotic nistatin. In our experiments we used raw smoked sausages that were infected with fungi. The identification of this infection showed the presence of Eurotium repens de Bary on the sausages. Treatment of the raw smoked sausages with cultural broth of L.lactis ssp. lactis 194 and K-205 inhibited growth of these microorganisms. After treatment the sausages had longer shelf-life and was in accordance with basal production data (Russian State Standard Specification 16131-86. Conclusion: The results of this study indicated that the treatment with

  8. 植物乳杆菌代谢产细菌素的培养基优化%Culture Medium Optimization of Lactobacillus Plantarum for Bacteriocin Production

    Institute of Scientific and Technical Information of China (English)

    佟世生; 解洛香; 徐乐; 胡涛; 刘萍

    2012-01-01

    In this paper, the culture medium of Lactobacillus plantarum for bacteriocin production was optimized. The results showed that the culture medium had an important effect on germ formation and production of bacteriocin, in which carbon source was significant Overall, 5% molasses, 0.5% yeast extract, 2% tryptone, 0.4% KH2PO4, 0.1% MgSO4-7H2O, 0.5% CaCO3, 0.05% MnSO4 and 0.3% Tween 80 were the optimal combination of culture medium.%本文对植物乳杆菌代谢产细菌素的培养基进行一系列优化.结果显示,不同培养基对菌株生长和细菌素产量有重要的影响,其中以碳源的影响最为显著.综合考虑,5%糖蜜、0.5%酵母膏、2%胰蛋白胨、0.4%KH2PO4、0.1%MgSO4·7H2O、0.5%CaCO3、0.05% MnSO4和0.3%吐温80是植物乳杆菌生长和代谢产细菌素的最优培养基组合.

  9. 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.

  10. 和田地区酸奶中产细菌素乳酸菌的筛选及细菌素特性的研究%Screening of bacteriocin-producing lactic acid bacteria from Hetian yoghourt and characterization of the bacteriocin

    Institute of Scientific and Technical Information of China (English)

    王东梅; 刘飞; 马翠云; 陈红征

    2012-01-01

    从和田地区酸奶中筛选出了乳酸菌A3,其所产抑菌物质在排除过氧化氢和有机酸的干扰及蛋白酶失活实验后,可以初步确定是一种细菌素。该细菌素对热较稳定,在酸性条件下表现出很好的抑菌活性,同时具有广谱的抑菌活性。根据该菌株的形态和生理生化特性,将A3菌株初步鉴定为肠膜明串珠菌(Leuconostoc mesenteroides)。%The lactic acid bacteria A3 was isolated from Hetian yoghourt. The bacteriostasis material was determined as bacteriocin after excluding interference of organic acid, H202 and inactivation of proteinase. The bacteriocin had good heat stability and high antibacterial activity under acid conditions. It also had broad-spectrum effects on bacteriostasis. Through detection of its appearance, physiological and biochemical characteristics, A3 was identified as Leuconostoc mesenteroides.

  11. Bacteriocin Antibacterial Activity Produced by Lactobacillus helveticus Isolated Jianchang Dry-cured Duck%瑞士乳杆菌产生的细菌素的抑菌活性研究

    Institute of Scientific and Technical Information of China (English)

    林巧

    2015-01-01

    The antibacterial activity of this experiment by studying bacteriocins produced by Lactobacillus helveticus was investigated at different temperatures, different pH, different types of enzymes on the antibacterial activity of bacteriocin. Results showed that: proteinase can be a certain extent the antibacterial activity of bacteriocin, trypsin inhibition of the strongest; the antibacterial activity of the bacteriocin on the temperature tolerance and strong, even after treated at 100 ℃ has antibacterial activity, the st rongest antibacterial activity when stored at-20℃;the bacterial factors pH of 1.5 to 4.0 with antibacterial activity and antibacterial activity of the strongest at pH 1.5.%主要通过研究对从建昌板鸭发酵过程中分离瑞士乳杆菌产生细菌素的抑菌活性,考察不同温度,不同pH,不同种类酶作用对细菌素抑菌活性的影响。结果证明:蛋白酶能一定程度抑制细菌素的抑菌活性,且胰蛋白酶的抑制程度最强;该细菌素的抑菌活性对温度的耐受力强,即使在100℃处理后仍具有抑菌活性,在-20℃条件下保存时抑菌活性最强;该细菌素pH在1.5~4.0时具有抑菌活性,在pH为1.5时抑菌活性最强。

  12. Study on Fermentation Condition of Lactobacillus on Producing Bacteriocin and Antibacterial Spectrum of Antibacterial Compounds%乳杆菌产细菌素的发酵条件及其抑菌谱的研究

    Institute of Scientific and Technical Information of China (English)

    陈忠军; 张保军; 于娜

    2013-01-01

    本研究以从内蒙古地区传统谷物发酵食品-酸粥中筛选出的产细菌素的乳杆菌为对象,对其产细菌素的发酵条件进行优化,并确定其抑菌谱。结果表明乳杆菌SZL-1的最佳发酵条件为:接种量7%,培养基起始pH 6.0,发酵时间24h,培养温度37℃。乳杆菌SZL-1产生的细菌素抑菌谱较广,对大多数革兰氏阴性和革兰氏阳性菌都有抑菌作用,但对酵母菌无抑菌作用。%The strains producing bacteriocin was screened from traditional grain fermentation food Acid-Gruel in Inner Mongolia. The fermentation condition of producing bacteriocin and antibacterial spectrum of antibacterial compounds was studied. By single factor experiments and orthogonal experiments , the fermentation condition for SZL-1 on production of bacteriocin was optimized. The result showed that the optimum inoculation quantity is 7%, initial pH was 6.0, culturing at 37℃ for 24 hours. Moreover bacteriocin produced by SZL-1 had obvious inhibit activity on antibacterial upon most of Gram-positive and Gram-negative bacteria , but no action on yeast. And antibacterial spectrum was wide.

  13. Ⅱa类乳酸菌细菌素的异源表达研究进展%Research Advances in Heterologous Expression of Class Ⅱa Bacteriocins from Lactic Acid Bacteria

    Institute of Scientific and Technical Information of China (English)

    刘国荣; 孙勇; 李平兰

    2012-01-01

    Ⅱa类乳酸菌细菌素由于其对单核细胞增生李斯特菌的强烈抑菌活性,已成为天然食品防腐剂研究与开发的热点。但是受生物合成调控系统控制,天然细菌素的产量往往很低而且提取过程较为复杂,很难满足相关研究和实际应用的需求。为此,许多研究者进行过Ⅱa类细菌素的异源表达研究,本文对该类细菌素在大肠杆菌、乳酸菌以及酵母菌中的异源表达研究作较为全面系统的综述,并指出目前存在的主要问题及今后的研究方向。%Class Ⅱ a bacteriocins from lactic acid bacteria, which have a strong antibacterial activity against Listeria monocytogenes, have become a hot topic in the research and development of natural preservatives. However, the bacteriocins are always produced at very low levels under the control of the biosynthesis regulatory system and their extraction is very complex, which makes it very difficult to meet the demands for relevant studies and practical applications. For this reason, the heterog- enous expression of class Ⅱ a bacteriocins has been widely studied in recent years. This paper summarizes a comprehensive systematic review of recent studies on the heterogenous expression of the bacteriocins in E. coli, lactic acid bacteria and yeast and points out the current main problems and future research directions.

  14. Quorum sensing in class Ⅱ bacteriocin-producing lactic acid bacteria and its application - A review%产Ⅱ类细菌素乳酸菌群体感应及其应用

    Institute of Scientific and Technical Information of China (English)

    张香美; 李平兰

    2011-01-01

    群体感应( quorum sensing,QS)是微生物通过感知与细胞密度相关的信号分子的浓度来调控基因表达的一种行为.许多产Ⅱ类细菌素乳酸菌通过自诱导肽介导的QS系统调控其细菌素的合成.本文综述了乳酸菌Ⅱ类细菌素合成的QS调控现象、调控机制、QS系统组分以及QS的应用.产Ⅱ类细菌素乳酸菌QS的研究,必将为揭示发酵调控机理、调控发酵过程提供新的研究平台,为食品级基因表达系统的开发提供新的选择.%Quorum sensing ( QS) refers to the behavior of microorganisms to control gene expression through detection the concentration of certain signal molecules, which is correlated with cell density. In many class II bacteriocin-producing lactic acid bacteria ( LAB ) , bacteriocin production is regulated by peptide pheromones via a QS mechanism. We reviewed, QS regulated class II bacteriocin production in LAB and its regulation mechanism, components of the QS system, as well as the application of QS mechanism. The study of QS mechanism of class II bacteriocin-producing LAB may provide a new platform for revealing the mechanism of fermentation control and regulating fermentation process. It also offers an alternative to the exploitation of food grade gene expression system.

  15. pH对费氏丙酸杆菌细菌素抑菌性的影响%Effect of pH on Antimicrobial Activity of Propionibacterium freudenreichii Bacteriocins

    Institute of Scientific and Technical Information of China (English)

    郑丽雪; 郭晨; 谢建松; 唐亚进; 王立梅; 齐斌

    2016-01-01

    以实验室保存的一株费氏丙酸杆菌CS1420(Propionibacterium freudenreichii CS1420)为试验菌株。首先考察了不同初始pH下对其发酵产细菌素的影响。结果表明:以大肠杆菌ATCC25922为指示菌,当培养基初始pH为6.0时,细菌素抑菌效果最好;以Saccharomyces cerevisiae 2-10515为指示菌,当培养基初始pH为5.5时,细菌素抑菌效果最好。然后用丙酸调节细菌素粗提物的pH进行抑菌试验,结果表明,pH对粗提得到的细菌素抑菌性影响很大,当用丙酸将细菌素溶液的pH调至5.5时,细菌素的抑菌活性有显著提高。%Propionibacterium freudenreichii CS1420 was as experimental strains. Firstly,the effects of different pH on fermentation of Propionibacterium freudenreichii Bacteriocins were investigated. The result showed:the antimicrobial activity were best by using Eoli ATCC25922 as indicator strains when the medium initial pH was 6.0,the antimicrobial activity were best by using Saccharomyces cerevisiae 2-10515 as indicator strains when the medium initial pH was 5.5. Then,bacteriocins crude extract pH were adjusted and then bacteriostatic exper-iments were carried out. The result showed:the effect of pH on crude extract bacteriocins was tremendous. The antimicrobial activity of bacteriocins improved significantly when crude extract bacteriocins solution pH were adjusted 5.5 with propionic acid.

  16. 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

  17. 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.

  18. 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

  19. 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

  20. Isolation of Pediococcus acidilactici Kp10 with ability to secrete bacteriocin-like inhibitory substance from milk products for applications in food industry

    Directory of Open Access Journals (Sweden)

    Abbasiliasi Sahar

    2012-11-01

    Full Text Available Abstract Background Lactic acid bacteria (LAB can be isolated from traditional milk products. LAB that secrete substances that inhibit pathogenic bacteria and are resistant to acid, bile, and pepsin but not vancomycin may have potential in food applications. Results LAB isolated from a range of traditional fermented products were screened for the production of bacteriocin-like inhibitory substances. A total of 222 LAB strains were isolated from fermented milk products in the form of fresh curds, dried curds, and ghara (a traditional flavor enhancer prepared from whey, and fermented cocoa bean. Eleven LAB isolates that produced antimicrobial substances were identified as Lactococcus lactis, Lactobacillus plantarum, and Pediococcus acidilactici strains by biochemical methods and 16S rDNA gene sequencing. Of these, the cell-free supernatant of Kp10 (P. acidilactici most strongly inhibited Listeria monocytogenes. Further analysis identified the antimicrobial substance produced by Kp10 as proteinaceous in nature and active over a wide pH range. Kp10 (P. acidilactici was found to be catalase-negative, able to produce β-galactosidase, resistant to bile salts (0.3% and acidic conditions (pH 3, and susceptible to most antibiotics. Conclusion Traditionally prepared fermented milk products are good sources of LAB with characteristics suitable for industrial applications. The isolate Kp10 (P. acidilactici shows potential for the production of probiotic and functional foods.

  1. Partial Purification and Characterization of the Mode of Action of Enterocin S37: A Bacteriocin Produced by Enterococcus faecalis S37 Isolated from Poultry Feces

    Science.gov (United States)

    Belguesmia, Y.; Choiset, Y.; Prévost, H.; Dalgalarrondo, M.; Chobert, J.-M.; Drider, D.

    2010-01-01

    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, α-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. PMID:20811593

  2. 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.

  3. 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.

  4. Screening of anti-Listeria bacteriocin of lactic acid bacteria and its physicochemical characteristics%乳酸菌中抗李斯特细菌素的筛选及理化性质分析

    Institute of Scientific and Technical Information of China (English)

    张红星; 刘丽; 刘慧; 谢远红; 陈湘宁

    2011-01-01

    Strain Y153,isolated from fish balls,produced antimicrobial substance which was inhibitory to Listeria monocytogenes 54003. Strain Y153 was identified as Streptococcus by using 16S rRNA gene sequence homology analysis. After eliminating the effect of organic acid and hydrogen peroxide,the antimicrobial substance with its proteinaceous nature was confirmed as bacteriocin. Bacteriocin Y153 was heat-stable and remained activity after incubation at a wide pH. It could be degraded by proteases existing in the human body. A preliminary study on the bacteriocin producted by Streptococcus strain Y153 had been made to lay the basis for the development of natural food preservative.%从鱼肉丸中分离筛选到1株具有抑菌活性的乳酸菌菌株Y153,对单核细胞增生李斯特菌ATCC54003的生长具有良好的抑制作用。16SrRNA序列同源性分析鉴定乳酸菌Y153为乳酸链球菌属(Streptococcus)。在排除有机酸、过氧化氢的干扰后,确定该抑菌物质为蛋白类物质,即细菌素,命名为细菌素Y153。理化性质分析表明,细菌素Y153具有较好的热稳定性、酸碱稳定性可被人体内蛋白酶降解的特性。由此对乳酸链球菌所产细菌素Y153有了初步的研究,为开发天然的食品防腐剂奠定理论基础。

  5. Optimization of bacteriocin production by Lactobacillus plantarum 8-6%植物乳杆菌(Lactobacillus plantarum)8-6产细菌素发酵条件的优化

    Institute of Scientific and Technical Information of China (English)

    李亚; 谈重芳; 王雁萍; 李宗伟

    2012-01-01

    Fermentation conditions of bacteriocin produced by Lactobacillus plantamm 8-6 were optimized. Effects of culture time, temperature, inoculum, initial pH value, carbon source and nitrogen on bacteriocin production were studied. The optimum media composition and fermentation conditions were obtained by single-factor and orthogonal experiments as follows: glucose 3%, tryptone 1.5%, peptone 1.5%, yeast extract 1%, magnesium sulfate 0.058%, tween-80 0.2%, culture temperature 30°C, culture time 28h, initial pH value 6.5 and inoculum 2%. Under the above conditions, the production of bacteriocin was 1825.56 IU/ml, which increased by 373.15% compared to that before optimization.%对植物乳杆菌(Lactobacillus plantarum) 8-6产细菌素的发酵条件进行了优化,分别研究了培养时间、温度、接种量、培养基起始pH值、培养基碳源、氮源等因素对细菌素产生的影响,通过单因素水平试验和正交试验,确定产细菌素的最佳培养基组合和最佳发酵条件为葡萄糖3%,胰蛋白胨2%,蛋白胨1%,酵母膏1%,硫酸镁0.058%,吐温-80 0.2%,30℃培养24h,培养基起始pH值为6.5,接种量2%.乳杆菌8-6优化后效价为1825.56IU/mL,比优化前提高了373.15%.

  6. 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.

  7. Research Antifungal Activity on Bacteriocin Produced by Lactic Acid Bacteria from Traditional Sour Cabbage%传统酸菜中具有抗真菌特性乳酸菌素的研究

    Institute of Scientific and Technical Information of China (English)

    李传娟; 双全; 栗永乐; 萨如拉; 桑木信辅; 琢田爱

    2012-01-01

    The antibacterial ability of lactic acid bacteria (LAB), which isolated from the sour cabbage juice prepared by herdsman in the east Inner Mogolia Region, were determined by Plate punch diffusion method, and the extracellulary bacteriocins of one screening strain was partial purified by gel filtration Sephadex G-15, and its biochemical characteristics were assessed in vitro. The results showed that strain S1-4 of LAB, which was screened out from 84 tested strains, had a broad spectrum antibacterial fungi property. Purified extracellulary bacteriocins from strain S1-4 was characterised as a proteinaceous substance. This bacteriocins compound, molecular mass ranged from 6.5 kDa to 8 kDa, has thermal stability and acid tolerance with an optimum antibacterial ability at pH 4.0.%通过平板打孔扩散法测定从内蒙古东部地区传统酸菜汁中分离的乳酸菌(LAB)的抑菌能力,再用葡聚糖凝胶G-15对筛选乳酸菌的胞外细菌素进行分离及特性研究。结果显示,84株供试乳酸菌中筛选出1株具有广谱抗真菌能力的乳酸菌S1-4。该乳酸菌所产生的胞外抑菌素属蛋白类物质,具有热稳定和耐酸特性,在pH4.0时抑菌效果最佳,其分子量约为6.5KDa~8kDa。

  8. 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...

  9. Sil: a Streptococcus iniae bacteriocin with dual role as an antimicrobial and an immunomodulator that inhibits innate immune response and promotes S. iniae infection.

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    Mo-fei Li

    Full Text Available Streptococcus iniae is a Gram-positive bacterium and a severe pathogen to a wide range of economically important fish species. In addition, S. iniae is also a zoonotic pathogen and can cause serious infections in humans. In this study, we identified from a pathogenic S. iniae strain a putative bacteriocin, Sil, and examined its biological activity. Sil is composed of 101 amino acid residues and shares 35.6% overall sequence identity with the lactococcin 972 of Lactococcus lactis. Immunoblot analysis showed that Sil was secreted by S. iniae into the extracellular milieu. Purified recombinant Sil (rSil exhibited a dose-dependent inhibitory effect on the growth of Bacillus subtilis but had no impact on the growths of other 16 Gram-positive bacteria and 10 Gram-negative bacteria representing 23 different bacterial species. Treatment of rSil by heating at 50°C abolished the activity of rSil. rSil bound to the surface of B. subtilis but induced no killing of the target cells. Cellular study revealed that rSil interacted with turbot (Scophthalmus maximus head kidney monocytes and inhibited the innate immune response of the cells, which led to enhanced cellular infection of S. iniae. Antibody blocking of the extracellular Sil produced by S. iniae significantly attenuated the infectivity of S. iniae. Consistent with these in vitro observations, in vivo study showed that administration of turbot with rSil prior to S. iniae infection significantly increased bacterial dissemination and colonization in fish tissues. Taken together, these results indicate that Sil is a novel virulence-associated bacteriostatic and an immunoregulator that promotes S. iniae infection by impairing the immune defense of host fish.

  10. Screening the Best Fermentation Conditions of Bacteriocin Produced by Leuconostoc mesenteroides%肠膜明串珠菌产细菌素最适发酵条件的筛选

    Institute of Scientific and Technical Information of China (English)

    王琳琳; 郑一敏; 杨宇清; 胡杨; 胥秀英; 傅善权

    2011-01-01

    为获得肠膜明串珠茵产细茵素的最佳发酵条件,采用琼脂扩散法测定发酵液对革兰氏阳性细菌、革兰氏阴性细菌的抑菌活性,结果发现:产细茵素的最佳培养基是MRS培养基,最适起始pH值为6.4,最适接种的体积分数和接种种龄分别为3%和24 h,产细菌素最适发酵温度和时间分别为30℃和24 h.通过优化发酵条件提高了细菌素的产量.%Objective: To obtain the optimal fermentation conditions of hacteriocin produced by Leuconostoc mesenteroides strain. Method: The antibacterial activity of the fermentation liquid against Gram-positive bacteria and Gram-negative bacteria was tested by the method of agar diffusion assay. Results: MRS was shown to be more suitable for producing bacteriocin than 108 #. The optimum initial pH, inoculation amount. seed age and fermentation temperature and time were 6. 5, 3%, 24 hours and 30 ℃ and 24 hours, respectively. Conclusion: The optimization of fermentation conditions improved bacteriocin production by L. mesenteroides.

  11. 不同破碎方法提取嗜酸乳杆菌细菌素的研究%Study on bacteriocin extracted by different cell disruption methods

    Institute of Scientific and Technical Information of China (English)

    张帅

    2013-01-01

    Bacteriocin was seperated and got after the cell of Lactobacillus acidophilus was disrupted by the microwave test,bead mill test,ultrasonication,freezing and thawing test,and quartz sand grinding test.The better physical method of the cell disruption was studied by the bacteriostatic activity of bacteriocin.The result showed that the diameter of inhibition zone by ultrasonication was the largest,which was 20.94 mm,so the effect of the cell disruption was best.%采用微波法、珠磨法、超声波法、反复冻融法、石英砂研磨法分别对嗜酸乳杆菌进行细胞破碎分离细菌素,通过研究嗜酸乳杆菌产细菌素抑菌活性来确定最佳细胞破碎物理方法.结果表明,超声波破碎法抑菌圈直径最大,为20.94 mm,细胞破碎效果最好.

  12. Screening of bacteriocin-producing lactic acid bacteria in hogormag from Xinjiang and study on its bacteriostatic activity%新疆酸驼乳中细菌素乳酸菌的筛选及其抑菌性

    Institute of Scientific and Technical Information of China (English)

    武运; 李远; 王冰峰; 张晓燕; 阿伊古扎丽; 巴吐尔

    2011-01-01

    From 23 strains of lactic acid bacteria isolated from Hazakh traditional fermented camel milk, 9 Strains were screened out to exhibit inhibitory activity on S. aureus, B. subtilis and E. coli by doubledeck agar diffusion and punch methods. One strain of MLS5 exhibits the strongest antibacterial activity. The antimicrobial substance produced by MLS5 was initially identified as protein bacteriocin by inhib itive effect of organic acids and hydrogen peroxide exclusion and protease susceptibility test. Temperature and pH tolerance test showed that the bacteriocin still has thermal stability at 121 ℃ for 20 minutes and antibacterial activity at pH 3 ~ 6. Fermentation curve of strain MLS5 showed that the strain was capacity of producing bacteriocin and acid at the temperature of 37 ℃. The bacteriocin was generated from mid-logarithmic growth phase and reached the maximum activity at stationary phase. The inhibitory spectrum results showed that the bacteriocin produced by MLS5 exhibits broad antibacterial spectrum. It can not only inhibit the Gram-positive bacteria, but also inhibit E. coli and Mucor.%通过双层琼脂扩散打孔法,从新疆哈萨克族传统发酵酸驼乳中分离的23株乳酸菌中,筛选出9株对金黄色葡萄球菌、枯草芽孢杆菌和大肠杆菌具有抑菌活性的菌株(其中茵株MLS5抑菌活性最强).通过有机酸、过氧化氢抑茵的排除试验和蛋白酶敏感性试验,初步确定MLS5产生的抑茵物质为蛋白质类细菌素.温度和pH耐受试验表明,该细菌素具有良好的热稳定性(121℃,20 min),pH 3~6具有抑茵活性.菌株MLS5的发酵曲线表明,菌株在37℃培养条件下具有良好的产细菌素和产酸能力,该细茵素在茵体生长对数中期产生,在生长稳定期抑茵活性达到最大.经抑茵谱试验表明,MLS5所产细菌素不仅能抑制革兰氏阳性细茵,而且对大肠杆菌和毛霉菌也有抑制作用,具有较广的抑茵谱.

  13. 变形链球菌ComCDE密度感应参与不同菌种的竞争%Quorum sensing system is involved in bacteriocin production and bacterial competition of Streptococcus mutans

    Institute of Scientific and Technical Information of China (English)

    张恺; 凌均棨; 刘佳; 霍丽珺; 麦俊妮

    2012-01-01

    目的 研究口腔变形链球菌( S.mutans )ComCDE密度感应系统参与血链球菌(S.sanguinis)的相互竞争作用.方法 采用LIVE\\DEAD BacLightTM荧光染色结合激光共聚焦显微镜,观察变形链球菌(简称变链菌)在CSP信号肽诱导下群体细菌自身死亡变化;通过荧光定量反转录聚合酶链反应(RT-PCR)测定细菌素以及细菌素免疫蛋白相关基因表达变化,分析变链菌ComCDE系统参与菌群生存竞争的调控机制.结果 在细菌竞争中,变形链球菌△comC、△comD 、△comE突变株失去不同菌种间的竞争力,无法抑制相邻Ssanguinis的正常生长;只有野生株保持竞争力,抑制相邻S.sanguinis生长,形成缺陷菌环.CSP信号肽诱导下,变链菌群体死菌/活菌率增高58.1%(P<0.05);细菌素及免疫蛋白相关SMU.151、SMU.423、SMU.1913c基因分别升高23.3倍(P=0.00)、15.9倍(P<0.05)、19.3倍(P<0.05).结论 变形链球菌ComCDE密度感应系统调控变链菌的变链素及免疫蛋白产生、参与不同菌种间竞争生存.%Objective To study the role of ComCDE quorum sensing system of Streptococcus mutans (S.mutans) in bacteriocin production and bacterial competition.Methods Growth competition between S.mutans and Streptococcus sanguis (S.sanguis) was analyzed through the bacterial competition assay.Cellular growth and death of S.mutans with and without CSP peptide was monitored by using the laser confocal microscopy and LIVE/DEAD BacLightTM staining.Bacteriocin and bacteriocin immunity protein related gene expression was determined by real-time RT-PCR.Results Competition assay showed that S.mutans △comC,△comD,and △comE mutant lost the ability of competition,and they could not suppress the normal growth of S.sanguinis,while S.mutans UA159 wild type strain inhibited the normal growth of the adjacent S.sanguinis.In the presence of CSP peptide,the ratio of Dead/live cells of S.mutans UA159 was increased 58.1% (P < 0.05),and

  14. 一株从酸菜中分离的产细菌素乳杆菌的鉴定及其所产抑菌物质的研究%Identification and study on bacteriocin-producing Lactobacillus screened from Sauerkraut

    Institute of Scientific and Technical Information of China (English)

    牛爱地; 韩建春

    2009-01-01

    A lactic acid bacteria A_5 strain was isolated from the sauerkraut. The results showed that the supernatant of A_5 strain was sensitive with pepsin and papain, the inhibitory material of A_5 strain was a kind of protein, which could be classed as bacteriocin. The bacteriocin had the strong heat endurance, and it still had the strong bacteriostatic activity at 121 ℃, 20 min. The bacteriocin had the strong bacteriostatic activity in pH 3.0-5.0. The bacteriocin showed inhibition to some gram-positive and gram-negative bacteria. Therefore, it was a kind of bacteriocin with broad-spectrum antimicrobial activity.%从酸菜汁中分离出一株有抑菌活性的菌株,经鉴定为乳杆菌A_5.温度、pH对菌株发酵上清液的影响以及发酵上清液对酶的敏感性的研究表明,发酵上清液中的抑菌物质对胃蛋白酶、木瓜蛋白酶较敏感,说明抑菌物质是一种蛋白质,确定为细菌素.该细菌素具有良好的热稳定性,在121℃20 min的高温条件下,仍具有较强的抑菌活性.菌株所产细菌素在酸性条件下有较强的抑菌活性(pH 3.0~5.0);菌株产生的细菌素可以较好地抑制革兰氏阳性、阴性菌,表明菌株所产细菌素是一类具有广谱抑菌活性的细菌素.

  15. Screen and Preliminary Identification of Lactic acid bacteria to Produce Broad-Spectrum Bacteriocin%产广谱细菌素乳酸菌CW3的筛选和初步鉴定

    Institute of Scientific and Technical Information of China (English)

    吕好新; 王巍东; 谈重芳; 杨飞飞; 焦迎春; 王雁萍; 李宗伟

    2013-01-01

    [Objective] CW3 strain was screened and preliminarily identified.[Method] Oxford cup double plate method was adopted to primarily screen spectrum bacteriocin,then excluding acid and hydrogen peroxide disturbance,the protein property of anti-bacteria material was detected,the strain of rescreening was identified.[Result] The supernatant of CW3 strain can inhibit the growth of indicator strains excluded hydrogen peroxide and organic acid.The inhibitive activity decreased largely after treatment with trpsin and pepsin,which can draw that the anti-microbial substances were bacteriocin.The results of identification of physiology and biochemistry preliminarily identified that CW3 strain was a Lactobacillus plantarum.[Conclusion] CW3 strain was a Lactobacillus plantarum,which can generate spectrum bacteriocin.%[目的]对CW3菌株进行筛选,并且进行初步鉴定.[方法]首先采用牛津杯双层平板法进行产广谱细菌素菌株的初筛,再将初筛得到的菌株进行排除酸和过氧化氢干扰,并检测抑菌物质的蛋白质性质,最终对复筛得到的菌株进行鉴定.[结果]试验得出,排除有机酸、过氧化氢等干扰因素后,发酵液仍有抑菌作用;用胰蛋白酶和胃蛋白酶处理后,发酵液抑菌活性急剧下降,确定产生的抑菌物质具有蛋白质性质,是一类细菌素.经过生理生化试验初步鉴定菌株CW3为植物乳杆菌.[结论]菌株CW3是一种能产广谱细菌素的植物乳杆菌.

  16. Bacteriocin-like activity of oral Fusobacterium nucleatum isolated from human and non-human primates Atividade semelhante a bacteriocina de Fusobacterium nucleatum orais isolados de primatas humanos e não-humanos

    Directory of Open Access Journals (Sweden)

    Elerson Gaetti-Jardim Júnior

    1999-12-01

    Full Text Available Fusobacterium nucleatum is indigenous of the human oral cavity and has been involved in different infectious processes. The production of bacteriocin-like substances may be important in regulation of bacterial microbiota in oral cavity. The ability to produce bacteriocin-like substances by 80 oral F. nucleatum isolates obtained from periodontal patients, healthy individuals and Cebus apella monkeys, was examinated. 17.5% of all tested isolates showed auto-antagonism and 78.8% iso- or hetero-antagonism. No isolate from monkey was capable to produce auto-inhibition. In this study, the antagonistic substances production was variable in all tested isolates. Most of the F. nucleatum showed antagonistic activity against tested reference strains. These data suggest a possible participation of these substances on the oral microbial ecology in humans and animals. However, the role of bacteriocins in regulating dental plaque microbiota in vivo is discussed.Fusobacterium nucleatum é indígena da cavidade oral humana e tem sido envolvido em diferentes processos infecciosos. A produção de substâncias semelhantes a bacteriocinas pode ser importante na regulação da microbiota bacteriana da cavidade oral. A capacidade de produzir substâncias tipo bacteriocina de 80 isolados de F. nucleatum orais, obtidos de pacientes com doença periodontal, indivíduos sadios e macaco Cebus apella, foi avaliada. 17,5% de todos os isolados mostrou auto-antagonismo e 78,8% iso- ou hetero-antagonismo. Nenhum isolado de macaco foi capaz de produzir auto-inibição. Neste estudo, a produção de substâncias antagonístas foi variável em todos os isolados testados. A maioria dos F. nucleatum mostrou atividade antagonísta para as cepas de referência testadas. Esses dados sugerem a possível participação dessas substâncias sobre a ecologia microbiana em humanos e animais. Entretanto, o papel das bacteriocinas na regulação da microbiota da placa dental in vivo

  17. 泡菜中产细菌素乳酸菌的筛选及特性研究%Screening and Characteristics of Bacteriocin-producing Lactic Acid Bacteria in PickIes

    Institute of Scientific and Technical Information of China (English)

    刘阳; 何义国; 赵兴秀; 赵长青; 张静; 邹伟

    2016-01-01

    Four lactic acid bacteria with good antibacterial properties are isolated from pickles by dilution coated plate method for separating,plate streak method for purifying,filtering paper method for preliminary screening,oxford cup method for secondary screening.Neutralization elimination of interference factors such as organic acid and hydrogen peroxide,fermented liquid still has strong bacteriostatic action.After being treated with protease and trypsin,the antibacterial performance of fermented liquid is significantly reduced, thus antibacterial material is determined as a kind of bacteriocin with protein properties.Through the morphology,growth condition and physiological and biochemical identification, preliminarily determine 4 strains of bacteria are all Lactobacillusplantarum.To further study the antibacterial ability of L-33 strain,its bacteriocin pH activity range is 5.0~9.0 and the antibacterial activity is the highest at pH 7.0.It has thermal stability and broad-spectrum bacteriocin inhibitory effect on gram positive bacteria and gram negative bacteria.%以泡菜为原材料,经稀释涂布平板法分离、平板划线法纯化、滤纸片法初筛和牛津杯法复筛得到4株有较好抑菌性能的乳酸菌。中和法排除有机酸及过氧化氢等干扰因素后,发酵液仍有较强的抑菌作用;用蛋白酶和胰蛋白酶处理后,发酵液抑菌性能明显降低,因而确定抑菌物质是一种具备蛋白质性质的细菌素。经形态学、生长条件和生理生化鉴定,初步确定4株菌均为植物乳杆菌。对抑菌能力较强的L-33菌株进一步研究,其产生的细菌素pH 活性范围为5.0~9.0,在pH 7.0时抑菌活性最高,且其具有热稳定性,是一种对革兰氏阳性菌和阴性菌都有抑菌效果的广谱细菌素。

  18. Screening, Identification and Toxicity of a Strain of Wide pH Spectrum Bacteriocin-Producing Lactic Acid Bacteria and Characterization of Bacteriocin Produced by It%产宽谱pH细菌素乳酸菌的筛选鉴定、毒力检测及细菌素特性研究

    Institute of Scientific and Technical Information of China (English)

    周佳; 刘书亮; 胡欣洁; 张元娥

    2012-01-01

    SAU-2,a bacteriocin-producing strain,was screened out of 34 strains isolated from milk residue in West Sichuan plateau.The strain was identified as Enterococcus based on colonial morphology,physiological and biochemical characteristics and 16S rDNA sequence phylogenetic analysis.SAU-2 had no hemolytic activity.All the virulence factors of agg,gelE,cylM,cylB,cylA,esp,efaAfm,cpd,cob,ccf,cyILL,cyILS,fsrB and hyLEfm were negative.These results indicate that SAU-2 is safe.In addition,bacteriocin produced by SAU-2 could tolerate heat treatment at 121 ℃ for 20 min,and exhibited antibacterial activity at pH 2.0-12.0,but was sensitive to trypsin and proteinase K.It showed strong inhibitory effect on relative strains of SAU-2 and Gram-positive bacteria,and could also inhibit one strain of Pseudomonas aeruginosa and one strain of Rhodotorula glutinis,but had no inhibitory effect on other Gram-negative bacteria and fungi.%采用琼脂扩散法从分离自川西高原奶渣的34株疑似乳酸球菌中筛选细菌素产生菌,初筛检测发酵上清液抑菌活性,复筛排除有机酸和H2O2干扰,检测蛋白酶敏感性,测定抑菌物质盐析液和粗提液抑菌活性,确定菌株SAU-2为细菌素产生菌。根据形态、生理生化指标和16S rDNA序列系统发育分析,将其鉴定为Enterococcus。肠球菌SAU-2溶血素表型阴性,agg、gelE、cylM、cylB、cylA、esp、efaAfm、cpd、cob、ccf、cyILL、cyILS、fsrB和hyLEfm等毒力因子基因型阴性,表明肠球菌SAU-2是安全的。所产细菌素可耐受121℃条件20min;在pH2.0~12.0有抑菌活性;对胰蛋白酶和蛋白酶K敏感,对木瓜蛋白酶和胃蛋白酶不敏感;主要对近缘乳酸菌和G+细菌有抑菌活性,除对1株铜绿假单胞菌和1株红酵母有抑菌活性外,对其余G-细菌和真菌无抑制作用。

  19. Cloning, production, and functional expression of the bacteriocin sakacin A (SakA) and two SakA-derived chimeras in lactic acid bacteria (LAB) and the yeasts Pichia pastoris and Kluyveromyces lactis.

    Science.gov (United States)

    Jiménez, Juan J; Borrero, Juan; Diep, Dzung B; Gútiez, Loreto; Nes, Ingolf F; Herranz, Carmen; Cintas, Luis M; Hernández, Pablo E

    2013-09-01

    Mature sakacin A (SakA, encoded by sapA) and its cognate immunity protein (SakI, encoded by sapiA), and two SakA-derived chimeras mimicking the N-terminal end of mature enterocin P (EntP/SakA) and mature enterocin A (EntA/SakA) together with SakI, were fused to different signal peptides (SP) and cloned into the protein expression vectors pNZ8048 and pMG36c for evaluation of their production and functional expression by different lactic acid bacteria. The amount, antimicrobial activity, and specific antimicrobial activity of SakA and its chimeras produced by Lactococcus lactis subsp. cremoris NZ9000 depended on the SP and the expression vector. Only L. lactis NZ9000 (pNUPS), producing EntP/SakA, showed higher bacteriocin production and antimicrobial activity than the natural SakA-producer Lactobacillus sakei Lb706. The lower antimicrobial activity of the SakA-producer L. lactis NZ9000 (pNUS) and that of the EntA/SakA-producer L. lactis NZ9000 (pNUAS) could be ascribed to secretion of truncated bacteriocins. On the other hand, of the Lb. sakei Lb706 cultures transformed with the pMG36c-derived vectors only Lb. sakei Lb706 (pGUS) overproducing SakA showed a higher antimicrobial activity than Lb. sakei Lb706. Finally, cloning of SakA and EntP/SakA into pPICZαA and pKLAC2 permitted the production of SakA and EntP/SakA by recombinant Pichia pastoris X-33 and Kluyveromyces lactis GG799 derivatives although their antimicrobial activity was lower than expected from their production.

  20. 贵州铜仁产广谱抑菌作用细菌素乳酸菌的筛选及鉴定%On the Sift and Identification of the Broad-spectrum Antibacterial Bacteriocin Produced in Tongren, Guizhou

    Institute of Scientific and Technical Information of China (English)

    胡美忠; 张新卓; 刘芸

    2014-01-01

    从贵州铜仁产发酵食品中分离纯化出70余株乳酸菌,采用Agar-spot-test初筛与排除酸、过氧化氢抑制后复筛出一株能产广谱抑菌作用细菌素的乳酸菌(编号G55),经生理生化及16S rDNA鉴定可知G55为植物乳杆菌。抑菌谱实验表明,G55产生的细菌素能抑制革兰阳性菌及革兰阴性菌的生长;蛋白酶实验表明,G55产生的细菌素对胃蛋白酶、蛋白酶K敏感,对胰蛋白酶、α凝乳蛋白酶部分敏感。%More than 70 strains of lactic acid bacteria are separated and purified from the fermented foods made in Tongren, Guizhou. First, they are preliminarily sifted by means of agar-spot-test and then excluded from the inhibition of the acid and hydrogen peroxide. After a second sift, a strain of lactic acid bacteria named G55 which can produce broad-spectrum antibacterial bacteriocin is chosen from them. After the physiobiochemical experiment and the 16SrDNA identification, it is concluded that G55 is an actobacillus plantarum. According to the antibacterial spectrum experiment, it shows that the bacteriocin produced by G55 can inhibit the growth of both gram-positive bacteria and gram-negative bacteria. Meanwhile, the experiment of protease shows that the bacteriorin is sensitive to pepsin and proteinase K and is partially sensitive to trypsin andαcurd protease.

  1. 开菲尔粒中产球菌样细菌素乳酸菌的分离与鉴定%The separation and Identification of lactobacillus to secrete Like-Coccidia bacteriocin in Kefir grains

    Institute of Scientific and Technical Information of China (English)

    王颖; 桑文彦; 姚笛; 高玉荣; 于洋

    2011-01-01

    To screen lactic acid bacteria of bacteriostasis using MRS selection culture medium.The agar diffusion method with Oxford cup methord was adopted,combining physical and chemical resistance of the characteristics identification,antibacterial spectrum determination colony morphology and characteristics,physiological and biochemical experiment,and the berger's manual identification were exercised.The physiological and biochemical reaction was lactic acid.The bacteria colony morphology and characteristics were Coccidia and have inhibition for most of the gram negative bacteria,this strain was lactic acid milk aureus the diacetyl lactic acid subspecies.Identification and separation results was in the bacteriocins coccoid lactic acid bacteria,and the bacteriocin was the like-protein peptide.%利用MRS选择培养基筛选开菲尔粒中具有抑菌作用的乳酸菌。采用牛津杯琼脂扩散法,结合对理化抗性特征的鉴定、抗菌谱测定、菌落形态与特征和生理生化实验鉴定,结合伯杰氏手册对分离到的菌株进行鉴定。生理生化反应为乳酸菌,菌落形态与特征为球菌,对多数的革兰氏阴性菌有抑制作用,该菌株为乳酸乳球菌二乙酰乳酸亚种。鉴定分离为产球菌样细菌素的乳酸菌,产生的是蛋白肽类的细菌素。

  2. 马奶酒中抗单增李斯特氏菌细菌素产生菌的筛选及鉴定%Screening for anti-Listeria bacteriocin-producing lactic acid bacteria from koumiss

    Institute of Scientific and Technical Information of China (English)

    吴敬; 芒来; 贺银凤

    2011-01-01

    144 lactic acid bacteria strains isolated from traditional fermented koumiss were screened for bacteriocin production by double agar diffusion method. After eliminating the effects of organic acid and catalase, the cell free supernatant of one strain named MKB63 showed strong anti-Listeria activity and were identified as Enterococcus faecium by physiological-biochemical characterization. After ammonium sulphate precipitation, dialysis and concentration,the activity was enhanced. But the inhibition activity was lost after treatment of trypsin and proteinase K. The result showed this inhibitory material had the features of protein, and could be classified as bacteriocin.%从内蒙古传统乳制品酸马奶酒中分离出144株乳酸菌,通过双层琼脂平板扩散法筛选出具有明显抑菌作用的菌株.在排除有机酸、H2O2等的干扰后,其中1株乳酸菌的发酵上清液对受试的单核细胞增生李斯特氏菌表现出明显抑制作用;进一步硫酸铵沉淀、透析及浓缩处理后,其抑菌活性显著增强,说明其代谢产物中含有蛋白质类抑菌物质,可能是细菌素.经生理、生化试验和形态学观察,将该菌株鉴定为屎肠球菌(Enterococcus faecium).

  3. 枯草芽孢杆菌MA139类细菌素抑菌活性的研究%Studies on the Antibacterial Activity of Bacteriocin-like Inhibitory Substances (BLIS) Produced from Bacillus subtilis MA139

    Institute of Scientific and Technical Information of China (English)

    胡婷; 陆文清

    2012-01-01

    为测定枯草芽孢杆菌MA139产生的类细菌素的抑菌活性.本试验采用管碟法对枯草芽孢杆菌MA139产生的类细菌素对多株革兰氏阳性菌、革兰氏阴性菌和真菌的抑菌活性进行测定.结果表明:类细菌素不但对芽孢杆菌属的其他菌种有抗菌活性,对病原菌和霉菌也有拮抗作用;不同指示菌对类细菌素的敏感性不一样,其中金黄色葡萄球菌对其最敏感.该类细菌素具有广谱抗菌作用,有作为畜禽饲料添加剂的潜力.%One experiment was conducted to determine the antibacterial activity of bacteriocin -like inhibitory substances (BLIS) produced from Bacillus subtilis MA139. The bacteriocin-like inhibitory substances were screened for antibacterial activity against indicator strains using agar spot assay. The results showed that they had broad spectrum of antagonistic activity against indicator strains, and Staphylococcus aureus showed greatest sensitivity to the BLIS. In conclusion, BOS from Bacillus subtilis MA139 had broad spectrum of antagonistic activity against various species of bacterial and fungal pathogens and could potentially be used as feed additives.

  4. Production of bacteriocin-like inhibitory substances (BLIS by Streptococcus salivarius strains isolated from the tongue and throat of children with and without sore throat Produção de substâncias inibidoras semelhantes à bacteriocina por cepas de Streptococcus salivarius, isoladas da língua e garganta de crianças com e sem dor de garganta

    Directory of Open Access Journals (Sweden)

    Vera Fantinato

    1999-12-01

    Full Text Available Streptococcus salivarius strains, isolated from children with and without sore throat, were tested for bacteriocin production against Streptococcus pyogenes. S. salivarius strains producing bacteriocin-like inhibitory substances (BLIS against S. pyogenes were more frequently found in children without sore throat. These results suggest that these children may be protected against sore throat by the presence of BLIS-positive S. salivarius strains.Cepas de Streptococcus salivarius, isoladas de crianças com e sem dor de garganta, foram testadas quanto à produção de bacteriocina contra Streptococcus pyogenes. Os resultados mostraram que as crianças que não tinham dor de garganta possuiam, na boca, cepas de bactérias produtoras de substâncias inibidoras semelhantes à bacteriocina contra S. pyogenes.

  5. Effect of the fermentation broth of a bacteriocin-producing lactobacillus plantarum YJG on the production performance and egg quality of laying hens%一株产细菌素植物乳酸杆菌YJG发酵液对蛋鸡生产性能以及蛋品质的影响

    Institute of Scientific and Technical Information of China (English)

    韩冰; 邓凯; 张日俊

    2011-01-01

    To study effect of the fermentation broth of a bacteriocin-producing Lactobacillus plantarum YJG on production performance and egg quality of laying hens. Two hundred and twenty five laying hens of 232-day-old were randomly divided into 5 treatment groups with 5 replicates, and the trials period was 34 days. The results showed that treatment with 500 AU/kg bacteriocin could enhance the average weight, and the treatments with bacteriocins could apparently reduce the feed egg ratio(P<0.05), Bacteriocins produced by Lactobacillus plantarum YJG could improve the production performance and egg quality of laying hens and provide new insight into research of feed additives.%研究一株植物乳酸杆菌细菌素对蛋鸡生产性能和蛋品质的影响.选用232日龄产蛋率和体重相近、健康状况良好的海兰灰蛋鸡225只,试验期为34 d.结果表明:日粮中添加500 AU/kg植物乳酸杆菌细菌素对蛋鸡的产蛋率和平均蛋重的提升幅度最大,各细菌素添加组对降低料蛋比均有显著的效果(P<0.05),对平均日采食量、蛋黄色泽、哈氏单位、蛋壳强度和蛋形指数都有不同程度的改善.植物乳酸杆菌细菌素可以明显改善蛋鸡生产性能和蛋品质,可以为饲料添加剂的研发提供新的思路.

  6. Bacteriocins as potential anticancer agents

    OpenAIRE

    Sukhraj eKaur; Sumanpreet eKaur

    2015-01-01

    Cancer remains one of the leading causes of deaths worldwide, despite advances in its treatment and detection. The conventional chemotherapeutic agents used for the treatment of cancer have nonspecific toxicity towards normal body cells that cause various side effects. Secondly, cancer cells are known to develop chemotherapy resistance in due course of treatment. Thus, the demand for novel anti-cancer agents is increasing day by day. Some of the experimental studies have reported the therapeu...

  7. Bacteriocins as Potential Anticancer Agents

    OpenAIRE

    Kaur, Sumanpreet; Kaur, Sukhraj

    2015-01-01

    Cancer remains one of the leading causes of deaths worldwide, despite advances in its treatment and detection. The conventional chemotherapeutic agents used for the treatment of cancer have non-specific toxicity toward normal body cells that cause various side effects. Secondly, cancer cells are known to develop chemotherapy resistance in due course of treatment. Thus, the demand for novel anti-cancer agents is increasing day by day. Some of the experimental studies have reported the therapeu...

  8. 乳酸菌细菌素的纯化及应用的研究进展%Advances in Purification and Application of the Bacteriocin Isolated from Lactic Acid Bacteria

    Institute of Scientific and Technical Information of China (English)

    张建飞

    2012-01-01

    随着人类生活水平和健康水平的提高,绿色食品(肉、蛋、奶)的需求越来越大,消费者更关心食品的安全性.世界各国,尤其是欧洲、日本等发达国家在大力开展研究药物饲料添加剂的代用品.积极鼓励和倡导绿色安全饲料添加剂的研究和推广,微生态制剂受到世人的瞩目.但是,科学家们仍需进一步探讨该类产品的稳定性和连续性与生理、生化、营养各方面的关系.国内外的学者正在致力于细菌素(抗菌肽(antibacterid peptides)或多肽抗生素(peptide antibiotics))的研究.随着国内外研究的进展和深入,人们相继发现这类多肽不但具有抗细菌、抗真菌的作用,还具有抗寄生虫、病毒、癌细胞等功能,在医药学和食品保鲜技术上,成为研究的热点.在食品安全的今天,细菌素作为一种高效安全的饲料添加剂正在成为可能,需要加大力度进行研究和开发,细菌素的基因工程、蛋白质工程及分子筛选法将继续研究和突破,最终真正能够替代抗生素成为人类生产绿色食品.%21st,with the development of human life and the level of health, the demand of green food (meat, eggs, milk) is growing, consumers are more concerned about food safety. Countries in the world, carry out the study of drug substitute for feed additives especially in Europe, Japan and other developed countries. Research and extension of green safe feed additive are encouraged and promoted actively, probiotics attract the world's attention. But scientists still need explore the relationship between stability and continuity of such product and physiological, biochemical, nutritional aspects. Domestic and foreign scholars are working on the study of bacteriocin (antibacterid peptides or peptide antibiotics), with the progress of study and in-depth at home and abroad, people have found that these peptides not only have anti-bacterial, anti-fungal effect, but also have anti-parasite, virus

  9. 响应曲面法优化乳杆菌产细菌素的条件研究%Optimization of the fermentative conditions for bacteriocin production of Lactobacillus plantarum by response surface methodology

    Institute of Scientific and Technical Information of China (English)

    罗海; 唐洁; 汪静心; 曾朝懿

    2012-01-01

    As one strain was isolated from traditional fermented pickle,Lactobacillus plantarum was investigated for its optimal condition of bacteriocin production. The mainly factors included the liquid volume,glucose concentration,and peptone concentration which were screened by Plackett-Burman design. The capability of bacteriocin produced was judged in accordance with size of inhibition zone diameter. With the help of Box- Behnken design,the maximum response value could be identified. The results showed good fitting between the estimated value and the real value through verification,and the model was reliable. The optimization of cultured medium and fermentation conditions of Lactobacillus plantarum was as follows .. peptone 30g/L,glucose 15g/L, diammonium hydrogen citrate 2g/L,K2HPO4 2g/L,NaAc 5g/L,MnSO4 -4H20 0.25g/L,MgSO4.7H20 0.58g/L, tween80 0.1% ,fluid volume 25mL,temperature 30℃ ,the fermentation period 24h,inoculation amount 1% and pH6.0. Under the fermentative conditions,bacteriocin production of Lactobacillus plantarum increased by 30%.%以分离自泡菜可产细菌素的乳杆菌作为实验茵.优化其产细菌素的最佳培养条件,以提高其产细菌素的能力。通过Plackett-Burman实验筛选出对乳杆菌产细菌素有显著影响的3个因素,分别为装液量、葡萄糖质量浓度以及蛋白胨质量浓度。以抑菌圈直径大小作为产细菌素能力大小的判断依据,通过最陡爬坡实验和Box-Behnken实验进一步优化,并对优化的结果进行验证,验证结果表明,预测值和实际值有良好的拟合性,此优化模型可靠。最后确定的乳杆菌产细菌素的优化培养基组成为:蛋白胨30g/L、葡萄糖15g/L、柠檬酸氢二铵2g/L、K2HP042g/L、乙酸钠5g/L、MnSO4·4H200.25g/L、MgS04·7H200.58g/L、吐温800.1%;最佳培养条件为:装液量25mL、温度30℃、培养时间24h、接种量1%、pH6.0。在此优化发酵条件下

  10. 产Ⅱ a类细菌素乳酸菌的筛选及鉴定%Screening and identification of class Ⅱa bacteriocin-producing lactic acid bacteria

    Institute of Scientific and Technical Information of China (English)

    岳喜庆; 闵钟熳; 郭晨; 蔡玮璠

    2011-01-01

    352 lactic acid bacterial strains were isolated from fermented Chinese cabbage juice, cucumber juice,barley juice, corn juice, fresh milk, traditional cheese, and red tea. One strain against Listeria monocytogenes and Escherichia coli was selected by double-agar diffusion method. After eliminating some interference factors, such as the organic acid and hydrogen peroxidex, the supernatant of the strain exhibited inhibitory effect against the indicator strain. However,when treated with trypsin, pepsin and papain, the inhibitory activity lost totally. Therefore, the inhibitory material which has the features of protein, could be considered as bacteriocin. The bacteriocin was independent of heat, and the inhibitory activity of which was kept over 90% after treated at pH 6. 5, 121 ℃ for 15 min. According to the characteristics of bacteria, the bacteriocin was classified into class Ⅱ a. The strain was identified and named Enterococcusfaecium BC-3 on the base of physiological and biochemical tests and 16S rRNA gene sequence homology analysis.%从自制的发酵肉、酸菜汁、黄瓜汁、大麦汁、玉米汁等以及市售鲜奶、传统干酪、红茶中分离出352株乳酸菌,通过琼脂平板扩散法筛选到l株对单核细胞增生李斯特菌和大肠杆菌有明显抑制作用的乳酸菌菌株.排除有机酸、过氧化氢等的干扰后,乳酸菌发酵液离心后的上清液仍有抑菌活性,用胰蛋白酶、胃蛋白酶、木瓜蛋白酶处理后失去抑菌活性,从而确定产生的抑菌物质具有蛋白质性质,是一种细菌素.该细菌素具有热稳定性,在pH6.5,121℃热处理15 min时,抑菌活性仍保持90%以上.经过生理生化试验和16S rRNA基因序列相似性分析,鉴定BC-3菌株为屎肠球菌,命名.Enterococcus.faecium BC-3.其产生的细菌素对单核细胞增生李斯特菌有特异活性,并且具有热稳定性,根据细菌素的分类特征,该细菌素属于Ⅱa类细菌素.

  11. 植物乳杆菌KLDS1.0391在酸奶体系中的细菌素产生特点%The bacteriocin production by Lactobacillus plantarum KLDS1.0391 in yoghurt

    Institute of Scientific and Technical Information of China (English)

    范修海; 苑晓慧; 陈启佳; 满丽莉; 李雪; 牛墨; 孟祥晨

    2013-01-01

    Lactobacillus plantarum KLDS 1.0391 which can produce bacteriocin is probiotic. It can be used as both probiotic and biocontrol strain in food. The aim of this paper was to investigate the bacteriocin production of this strain in yoghourt during fermentation and storage of yoghourt when co-cultured with starter culture. The results showed that inhibition diameter was increased during fermentation. The antimicrobial activity of group added with L. plantarum KLDS1.0391 was significantly higher than that of control group (P <0. 01 ) during the fermentation of 6 h. There was no obvious difference between the sensory characteristics of yoghourt containing L. plantarum KLDS1.0391 and that of the control yoghourt. It was potential to explore the functional yoghourt using L. plantarum KLDS1. 0391.%植物乳杆菌KLDS1.0391能够合成细菌素,也是益生菌,在食品中既可作为益生菌使用,也可作为辅助发酵剂用于生物防控,该研究主要考察了KLDS1.0391菌株在酸奶体系中细菌素的产生特点.研究结果表明,在发酵的6h期间,抑菌活性随发酵时间延长而增强,发酵结束时,添加植物乳杆菌KLDS1.0391酸奶组的抑菌活性显著高于仅使用酸奶发酵剂的对照组(P<0.01).与对照组相比,加入辅助发酵剂的实验组的感官品质未发生明显的变化.植物乳杆菌KLDS1.0391具备开发益生酸奶的潜力.

  12. Isolation and Identification of Bacteriocin-producing Lactic Acid Bacteria from Meat Production%肉制品中产细菌素乳酸菌的分离及鉴定

    Institute of Scientific and Technical Information of China (English)

    刘丽; 郝彦玲; 张红星; 谢英

    2011-01-01

    从北京市售肉制品中分离筛选出1株具有抑菌活性的乳酸茵菌株L5-6,对单核细胞增生李斯特氏菌ATCC54003的生长具有良好的抑制作用.排除有机酸、过氧化氢的干扰后,确定该抑茵物质为蛋白类物质,即细菌素.16S rRNA序列同源性分析鉴定L5-6为戊糖片球菌.对L5-6中编码细菌素的结构基因进行克隆,推断L5-6所产的细茵素是片球菌素.片球菌素应用于肉制品防腐具有潜在的开发价值和广阔的市场前景,课题组对L5-6进行了初步的研究,为开发天然安全的食品保鲜防腐剂奠定基础.%Strain L5-6, isolated from meat production in Beijing, produced antimicrobial substance which was inhibitory to Listeria monocytogenes 54003. After eliminating the effect of organic acid and hydrogen peroxide,the antimicrobial substance with its proteinaceous nature was confirmed as bacteriocin. And also strain L5-6 was identified as Pediococcus pentosaceus by using 16S rRNA gene sequence homology analysis. Pediocin shows potential developing value and broad market prospect, especially in the meat products. The bacteriocin produced by L5-6 was identified as pediocin after cloning its structural gene. In this paper a preliminary study on L5-6 had been made to lay the basis for the development of natural food preservative.

  13. Antibacterial activity of bacteriocin from Lactobacillus plantarum CW5%植物乳杆菌(Lactobacillus plantarum)CW5的筛选及细菌素抑菌活性的研究

    Institute of Scientific and Technical Information of China (English)

    李亚; 谈重芳; 王雁萍; 李宗伟; 金庆生

    2011-01-01

    为了提高抑菌活性,对植物乳杆菌(Lactobacillus plantarum)CW5产细菌素的发酵条件进行了优化,分别研究了培养时间、温度、接种量、培养基起始pH、培养基碳源、氮源等因素对细菌素产生的影响,通过单因素水平实验和正交实验,确定产细菌素的最佳培养基组合和最佳发酵条件为:葡萄糖3%,胰蛋白胨1.5%,蛋白胨1.5%,酵母膏1%,硫酸镁0.058%,吐温800.2%,30℃培养24h,培养基起始pH为6.5,接种量2%。CW5在优化前效价为367.82IU/mL,优化后效价为1619.85IU/mL,提高了340.39%。%In order to improve the antibacterial activity, to optimize bacteriocin production, researching was done on the respect of incubation condition and the media components. The optimum media component was: glucose 3%, tryptone 1.5%, peptone 1.5%, yeast extract 1%, magnesium sulfate 0.058%, tween 80 0.2%. And the optimum temperature was 30 ℃, the optimum incubation time was 28 h, the optimum broth initial pH was 6.5, inoculation amount 2%. Under the above conditions, the production of bacteriocin was increased by 340.39%.

  14. 产细菌素植物乳杆菌纯种半固态发酵对泡菜品质的影响%Effect of Lactobacillus plantarum producing bacteriocine on pickle quality in semi-solid-state fermentation

    Institute of Scientific and Technical Information of China (English)

    韩新锋; 刘书亮; 张艾青; 杜晓华

    2012-01-01

    以产细菌素植物乳杆菌纯种半固态发酵制作什锦泡菜,同时以其纯种液态发酵泡菜和传统自然发酵泡菜为对照,比较三种泡菜在发酵过程和贮藏期间感官、理化指标与微生物菌相变化规律,评价半固态发酵对泡菜品质的影响.结果表明,该菌株纯种发酵制作的泡菜感官品质优于自然发酵泡菜,细菌、酵母菌、霉菌、大肠菌群数量均显著低于自然发酵泡菜;其中,纯种半固态发酵泡菜发酵过程pH值下降最迅速、泡菜中乳酸菌活菌数量高(108cfu/g)、亚硝酸盐含量低且无明显“亚硝峰”出现;说明产细菌素植物乳杆菌纯种半固态发酵制作什锦泡菜品质优于纯种液态发酵和自然发酵泡菜.%Mixed pickles were prepared by Lactobacillus plantarum producing bacteriocine with semi-solid fermentation; meanwhile pickles prepared by pure liquid fermentation and traditional natural fermentation were set as controls. Oranoleptic indicator, physical and chemical indicator, microorganism changes were compared during fermentation and storage to evaluate the effect of semi-solid fermentation. The results showed that the oranoleptic indicator of the pickles with pure semi-solid fermentation was superior to those with natural fermentation; the numbers of total plate counts, yeasts, moulds, coliform group were significantly lower than those of natural fermentation, respectively. The pH value of the pickles prepared by semi-solid fermentation decreased quickly, the numbers of viable lactic acid bacteria in the pickles with semi-solid fermentation were 108cfu/g, and the nitrites contents were low which had no obvious nitrites peak. The results indicated that the mixed pickles prepared by L. plantarum producing bacteriocine with pure semi-solid fermentation had a high quality among three kinds of fermentation.

  15. 植物乳杆菌B28产细菌素的发酵条件研究%Optimization of bacteriocin production by Lactobacillus plantarum B28

    Institute of Scientific and Technical Information of China (English)

    程建军; 李想; 郭明若; 吴琼

    2011-01-01

    Lactobacillus plantarum B28, which is a strain isolated from traditional Bulgarian oat beverage, produces a bacteriocin which is inhibitory to Baeillus cereus.The growth characteristic of Lactobacillus plantarum B28 and the optimal stage of producing bacteriocin were studied.The different cultures and different concentratiom of ammomum sulphate effect on bacteriocm activity was observed.The growth cycle of B28 was studied at 37 ℃ which indicated its stationary phase starting from the 14 th hour to the 16th hour.The bacteriostatic activity of plantaricin,produced by the strain has been improving constantly.It reached the peak value at 24 h.L.Plantarum grew better in media in presence of yeast extract, soybean protein, lactose, D-fructose, sucrose, or D- maltose.D-xylos was not suitalbe for L.Plantarum.There was no coniderable effect when it grew in KH2PO4 and NaH2PO4.The optimized medium was achieved.%从来自保加利亚传统燕麦饮料中分离得到的植物乳杆菌B28出发,以腊样芽胞杆菌Baeillus cereus为指示菌,研究了植物乳杆菌B28生长特性以及产生细菌素的最佳时期;不同氮源、碳源和磷酸盐对细菌素抑菌活性性影响以及不同浓度硫酸铵溶液对细菌素的盐析效果.结果表明,植物乳杆菌B28在37℃条件下培养,14~16 h,生长进入稳定期;产生细菌素最佳发酵时间为24 h;70%的硫酸酸铵是适植物乳杆菌细菌素的盐析质量分数为.与对照培养基对比,植物乳杆菌B28的生长情况是酵母提取物>大豆蛋白>胰蛋白胨、蛋白胨、肉膏;乳糖>D-果糖、蔗糖、D-麦芽糖>D-木糖;磷酸盐对植物乳杆菌B28的生长影响不大.并得到了产生细菌素的最佳培养基配方.

  16. 新疆高寒牧区产细菌素低温乳酸菌的筛选%Screening of bacteriocin-producing low-temperature lactic acid bacteria in high, cold pasture areas in Xinjiang

    Institute of Scientific and Technical Information of China (English)

    王俊钢; 刘成江; 郭安民; 李宇辉; 韩冬印; 李开雄

    2013-01-01

    Forty-five lactic acid bacteria were screened from the samples collected from the high, cold pasture areas in Xinjiang, and three of them with antimicrobial properties were screened out through the test. After exclusion of organic acids and catalase, these three lactic acid bacteria still had a certain bacteriostasis performance. Meanwhile, the antibacterial activity was greatly reduced after treated with trypsin, which indicated that the metabolite was bacte-riocins, the protein with antibacterial property. These three lactic acid bacteria were identified to be: Lactobacillus plantarum, Lactobacillus pentosus and Lactococcus lactis, respectively.%从新疆高寒牧区牧民自制乳制品分离得到45株乳酸菌.采用排除有机酸和过氧化氢中和试验对分离的乳酸菌进行处理,结果表明三株乳酸菌有抑菌特性.用胰蛋白酶对发酵液进行处理后,其抑菌活性大大降低,说明代谢产物是具有蛋白属性的抑菌物质,判断为细菌素.鉴定结果初步认为,这三株乳酸菌分别属于植物乳杆菌、戊糖乳杆菌和乳酸乳球菌.

  17. A rapid and accurate 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide colorimetric assay for quantification of bacteriocins with nisin as an example

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The objective of this study is to propose a more accurate and faster MTT [3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide] colorimetric assay (MCA) for quantitative measurement of polypeptide bacteriocins in solutions with nisin as an example. After an initial incubation of nisin and indicator bacterium Micrococcus luteus NCIB 8166 in tubes, MTT was added for another incubation period. After that, nisin was quantified by estimating the number of viable bacteria based on measuring the amount of purple formazan produced by cleavage of yellow tetrazolium salt MTT. Then MCA was compared to a standard agar diffusion assay (ADA). The results suggested a high correlation coefficient (r2=0.975±0.004) between optical density (OD) and the inhibitory effect of nisin on a bacterial strain Micrococcus luteus NCIB 8166 at a range of 0.125~32 IU/ml.The MCA described in this study was very quick. Quantification of nisin took only 7~8 h and the detection limit was at the level of 0.125 IU/ml when compared to 12 IU/ml and 24~28 h for ADA. The MCA provides an accurate and rapid method for quantification of nisin in solutions and is expected to be used for quantification of other antimicrobial substances.

  18. 产细菌素乳酸菌的选育及其抑菌特性的研究%Screening of bacteriocin-producing lactic acid bacteria and the characteristics of antibacterial compound

    Institute of Scientific and Technical Information of China (English)

    吴荣荣; 张良; 王倩

    2009-01-01

    采用牛津杯琼脂扩散法,从实验室保存的乳酸菌中筛选到具有较高抑菌活性的菌株嗜酸乳杆菌A、戊糖片球菌M和戊糖片球菌T,它们产生的抑菌物质经排除酸、过氧化氢后,仍具有抑菌活性,然而经蛋白酶处理后其抑菌活性明显下降,确定其抑菌物质为细菌素,进一步的抑菌实验表明,3株菌所产细菌素具有较宽的抑菌谱,适宜用作生物型防腐剂.%Three strains, which showed obvious antibacterial activity, were isolated from lactic acid bacteria, including Lactobacillus.Acidophilus (A), Pediococcus pentosaceus(M)and Pediococcus pentosaceus(T)by the agar diffusion cup-plate method.The supernatants after eliminated organic acid and hydrogen peroxide still retained bacteriostatic activity.The effect of inhibition decreased after treatment with protease K, The above results indicated that the antibacterial substance was a kind of protein.The inhibitory spectrum from the above supernatants was broad.The bacteriocin produced by three strains was suitable for the biotype preservatives.

  19. Screening and Identification of Bacteriocin-like Substance Producing Bacillus%一株产细菌素物质芽孢杆菌的筛选和鉴定

    Institute of Scientific and Technical Information of China (English)

    李俊峰; 李红芳; 段孝辉; 宿烽; 田智刚

    2011-01-01

    One Bacillus strain named SLY—3 producing bacteriocin-like substance ( BLS) was screened from the soil polluted by oil. The G +bacteria and molds were effectively inhibited by BLS produced by strain SLY—3. With the analysis of colony morphology, physiological and biochemistry experiments and 16S rDNA gene sequence, the strain SLY—3 was identified as Bacillus subtilis. The BLS secreted by Bacillus subtilis SLY—3 has the highest inhibitory activity when it is cultured for 24 h at initial pH 7.0 and 28 ℃ .%从石油污染的土壤中筛选出一株能产生细菌素类物质的芽孢杆菌,命名为SLY-3.该菌株分泌的活性物质抑菌活性好,对细菌主要是革兰氏阳性菌、霉菌都有抑制作用.从表型、生理生化反应及16S rDNA序列比对方面进行分析,最终确定菌株SLY-3 为枯草芽孢杆菌(Bacillus subtilis).培养基初始pH为7.0,28℃振荡培养24 h后,发酵产物抑菌活性最高.

  20. Study of Morphology Effects of Streptococcus Sanguis Bacteriocin on Candida Albicans and Candida Tropicalis%血链球菌细菌素对白色念珠菌及热带念珠菌菌体形态影响的研究

    Institute of Scientific and Technical Information of China (English)

    马晟利; 李慧; 佟忠山; 赵英男; 夏雪; 董雪

    2013-01-01

    Objective: To study the inhibition and morphological impact of Streptococcus sanguis bacteriocin on Candida albicans(C. a) and Candida tropicalis(C. t). Methods: Streptococcus sanguis bacteriocin was extracted by low-temperature high-speed centrifugation, ultrasonic disruption, and then was respectively applied to separate and mixed cultured C. a and C. t under 37℃ 80rpm oscillating culture. At 12h, we used plate colony counting method to determine the antibacterial activity of Streptococcus sanguis bacteriocin with different concentrations. We measured each group bacterial suspension OD value every 2 hours, drew the growth curve, studied the effect of Streptococcus sanguis bacteriocin on growth curve of C. a and C. t. We observed morphology by optical microscopy and scanning electron microscopy in the process of cultivation. Results: After the inhibition of lg/L Streptococcus sanguis bacteriocin, the number of the colonies of separate and mixed cultured C. a and C. t were less than the control group. The difference was statistically significant. The growth curve of C. a and C. t changed significantly in 6 - 14h, and the logarithmic growth phase was delayed 8 hours. Discoid depression was appeared on surface of spore and hyphae after inhibition. Conclusion: Streptococcus sanguis bacteriocin could significantly inhibit separate and mixed cultured C. a and C. t, delay the logarithmic growth phase and change the morphology of C. a and C. t.%目的:研究血链球菌细菌素对白色念珠菌(C.a)及热带念珠菌(C.t)的抑制作用及形态学影响.方法:通过低温高速离心,超声破碎等方法提取血链素,使血链素分别作用于单独及混合培养的C.a及C.t,于37℃下80r/min振荡培养.培养12h时,以平板菌落计数法测定不同浓度血链素的抑菌活性;每2h测1次各组菌悬液的A值,并绘制生长曲线,观察血链素对C.a及C.t生长曲线的影响.在血链素对C.a及C.t的作用过程中,利用光学显微镜及扫

  1. 1株产细菌素植物乳杆菌的筛选及所产细菌素的理化性质分析%Study on Screening of Lactobacillus Plantarum for Producing Bacteriocin and its Physicochemical Characteristics

    Institute of Scientific and Technical Information of China (English)

    刘丽; 郝彦玲; 张红星; 谢英; 周绪宝

    2011-01-01

    Strain LH-09, isolated from ham products in Zhejiang province, produced antimicrobial substance which was inhibitory to Listeria monocytogenes 54003. Strain LH-09 was identified as Lactobacillus plantarum by using 16S rRNA gene sequence homology analysis. After eliminating the effect of organic acid and hydrogen peroxide, the antimicrobial substance with its proteinaceous nature was confirmed as bacteriocin. Bacteriocin LH-09 was heat-stable and remained activity after incubation at a wide pH. It could be degraded by proteases existing in the human body. Tricine-SDS-PACE showed that its molecular weight was between 2-6 kDa. In this paper a preliminary study on the bacteriocin producted by Lactobacillus plantarum had been made to lay the basis for the development of natural food preservative.%从浙江省生产的一种火腿制品中分离筛选到1株具有抑菌活性的乳酸菌菌株LH-09,对单核细胞增生李斯特菌ATCC54003的生长具有良好的抑制作用.16SrRNA序列同源性分析鉴定乳酸菌LH-09为植物乳杆菌.在排除有机酸、过氧化氢的干扰后,确定该抑菌物质为蛋白类物质,即细菌素.理化性质分析表明细菌素LH-09具有较好的热稳定性、酸碱稳定性,可被人体内蛋白酶降解.N-羟甲基甲基甘氨酸-SDS-PAGE电泳确定细菌素LH-09的分子质量在2~6 kDa之间.

  2. Características da bacteriocina produzida por Lactococcus lactis ssp. hordniae CTC 484 e seu efeito sobre Listeria monocytogenes em carne bovina Characterisation of the bacteriocin produced by Lactococcus lactis ssp. hordniae CTC 484 and the effect of this compound on Listeria monocytogenes in beef

    Directory of Open Access Journals (Sweden)

    Renata Bromberg

    2006-03-01

    Full Text Available O isolamento de linhagens de bactérias lácticas produtoras de bacteriocinas em carnes e seus produtos derivados resultou na detecção de Lactococcus lactis ssp. hordniae CTC 484, proveniente de frango. A bacteriocina inibiu não apenas uma outra bactéria láctica (Lactobacillus helveticus, mas também microorganismos patogênicos (Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, Clostridium perfringens e Enterococcus faecalis. Ela foi inativada por causa de enzimas como: alfa-quimotripsina, tripsina, pronase E, ficina, pepsina, papaína e lipase. Além disso, a bacteriocina mostrou-se termoestável, mesmo a temperaturas de autoclavagem (121°C/10 min e foi produzida em condições de armazenamento sob refrigeração. A bacteriocina mostrou-se ativa dentro de uma ampla faixa de valores de pH (2-10, porém a maior atividade ocorreu em valores menores de pH. A eficiência da linhagem CTC 484, assim como a de sua bacteriocina na redução e inibição do crescimento de Listeria monocytogenes em carne bovina estéril, foram avaliadas. Os resultados indicaram que o tratamento da carne por meio da inoculação desta bactéria contribuiu para o aumento da segurança e extensão da vida útil deste alimento.Screening for the bacteriocin production of strains of lactic acid bacteria from various meat and meat products resulted in the detection of a bacteriocin-producing Lactococcus lactis ssp. hordniae CTC 484, isolated from chicken. The bacteriocin inhibited not only closely related lactic acid bacterium (Lactobacillus helveticus, but also pathogenic microorganisms (Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, Clostridium perfringens, and Enterococcus faecalis. This compound was inactivated by alpha-chymotrypsin, trypsin, pronase E, ficin, pepsin, papain, and also by lipase. It was heat stable even at autoclaving temperature (121°C/10 min and was produced under refrigerated storage. It was also active over a wide

  3. Optimization of Fermentation Conditions for Bacteriocin Production by Lactobacillus acidophilus NX2-6%嗜酸乳杆菌NX2-6产细菌素的发酵条件优化

    Institute of Scientific and Technical Information of China (English)

    乌云达来; 陆兆新; 吕凤霞; 别小妹; 卢亚萍; 孙会刚; 查干其劳

    2012-01-01

    Three culture medium components including glucose,sodium acetate and sodium citrate and fermentation time were identified as key factors that affect bacteriocin production by Lactobacillus acidophilus NX2-6 using a Plackett-Burman design and their optimal levels were investigated using response surface methodology based on a Box-Behnken experimental desiign.The optimal levels of glucose,sodium acetate and sodium citrate concentrations and fermentation time were determined to be 60.0 g/L,8.0 g/L,5.0 g/L and 36 h,respectively based on the established quadratic polynormial regression equation for inhibition zone diameter of fermentaton broth.Under these conditions,the predicted inhibition zone diameter of fermentaton broth was 0.9918.The optimized culture medium resulted in an increase of approximately 80.0% in the antibacterial activity of fermentation broth compared to the basic culture medium.Therefore,response surface methodology can provide an economic,effective and reasonal strategy for the optimization of fermentation conditions for bacteriocin production by Lactobacillus acidophilus NX2-6.%在Plackett-Burman试验结果基础上,采用响应曲面法(Box-Behnken设计)对嗜酸乳杆菌NX2-6发酵产细菌素的关键影响因素,即葡萄糖质量浓度、乙酸钠质量浓度、柠檬酸三钠水合物质量浓度及培养时间的最佳水平范围进行研究和探讨。通过对发酵液抑菌圈直径的二次多项回归方程求解得知,在葡萄糖质量浓度、乙酸钠质量浓度、柠檬酸三钠水合物质量浓度和培养时间分别为60.0、8.0、5.0g/L和36h时,菌株NX2-6的发酵液抑菌圈直径预测值为21.37mm,验证实验抑菌圈直径实测值与预测值的相关系数R2为0.9918。优化后培养基与基础培养基相比,发酵液抗菌活性增加约80.0%,由此可见,利用响应曲面法对嗜酸乳杆菌NX2-6发酵产细菌素条件进行优化是经济有效且科学合理的。

  4. The separation and Identification of lactobacillus of bacillus bacteriocin in cheese%奶酪中产杆菌样细菌素乳酸茵的分离与鉴定

    Institute of Scientific and Technical Information of China (English)

    周瑶; 王颖; 安字; 姚笛; 张红

    2012-01-01

    To screen and identify lactic acid bacteria of cheese using MRS culture medium, the identification of physiological and biochemical characteristics was adopted, combining Oxford cup method, the antibacterial spectrum determination colonial morphology and characteristics were carried on, and the identification of morphology and physiological and biochemical experiment method were exercised in turn. The identification results of the physiological and biochemical reaction was lactic acid. The bacteria colony morphology was Bacilli,which would have been inhibited for most of the gram negative bacteria,this strain was Bulgaria lactobaeillus.Identification and separation results were Lactobacillus bulgaricus, and the bacteriocin was the protein peptide.%通过MRS培养基筛选奶酪中分泌细菌素的乳酸菌,并鉴定菌种。依次研究菌落形态与特征,生理生化特征,结合牛津杯法分析抗菌谱和理化代谢物,通过形态和生理生化实验方法对筛选菌株进行鉴定。生理生化反应为乳酸菌,菌落形态与特征为杆菌,对部分革兰氏阴性菌有抑制作用,为保加利亚乳杆菌。分离菌株为乳酸杆菌,分泌细菌素是蛋白物质。

  5. MRS培养基组分对Lactobacillus J23合成抗菌肽Bac-J23的影响%Effect of MRS medium components on bacteriocin Bac-J23 production from Lactobacillus J23

    Institute of Scientific and Technical Information of China (English)

    易华西; 韩雪; 杜明; 张兰威

    2012-01-01

    The effect of MRS medium ingredient on the bacteriocin Bac-J23 produced by Lactobacillus J23 were studied. The results showed that 5g/L acetic acid sodium, sucrose and Yeast extraction could stimulate the growth of strain Lactobacillus J23 and induce Bac-J23 production. Higher concentration KH2PO4 (15g/L~20g/L) and 0.2g/L MgSO4 were propitious to Bac-J23 production, while MnSO4 and Tween-80 had no influence to the growth of Lactobacillus J23 and the production of Bac-J23.%研究了培养基MRS组分对乳酸菌Lactobacillus J23产生广谱抗菌肽Bac-J23的影响,并对其组成进行了优化.结果表明,当培养基中浓度为5g/L的乙酸钠对Bac-J23的合成具有刺激诱导作用,蔗糖对Bac-J23合成的最有利,酵母提取物对Lactobacillus J23的生长和Bac-J23的合成均具有明显的促进作用,KH2PO4(15g/L~20g/L)有利于Bac-J23的合成,MgSO4 (0.2g/L)对合成Bac-J23最有利,MnSO4和Tween-80对Bac-J23合成及Lactobacillus J23生长均没有明显影响.

  6. Binding sequences for RdgB, a DNA damage-responsive transcriptional activator, and temperature-dependent expression of bacteriocin and pectin lyase genes in Pectobacterium carotovorum subsp. carotovorum.

    Science.gov (United States)

    Yamada, Kazuteru; Kaneko, Jun; Kamio, Yoshiyuki; Itoh, Yoshifumi

    2008-10-01

    Pectobacterium carotovorum subsp. carotovorum strain Er simultaneously produces the phage tail-like bacteriocin carotovoricin (Ctv) and pectin lyase (Pnl) in response to DNA-damaging agents. The regulatory protein RdgB of the Mor/C family of proteins activates transcription of pnl through binding to the promoter. However, the optimal temperature for the synthesis of Ctv (23 degrees C) differs from that for synthesis of Pnl (30 degrees C), raising the question of whether RdgB directly activates ctv transcription. Here we report that RdgB directly regulates Ctv synthesis. Gel mobility shift assays demonstrated RdgB binding to the P(0), P(1), and P(2) promoters of the ctv operons, and DNase I footprinting determined RdgB-binding sequences (RdgB boxes) on these and on the pnl promoters. The RdgB box of the pnl promoter included a perfect 7-bp inverted repeat with high binding affinity to the regulator (K(d) [dissociation constant] = 150 nM). In contrast, RdgB boxes of the ctv promoters contained an imperfect inverted repeat with two or three mismatches that consequently reduced binding affinity (K(d) = 250 to 350 nM). Transcription of the rdgB and ctv genes was about doubled at 23 degrees C compared with that at 30 degrees C. In contrast, the amount of pnl transcription tripled at 30 degrees C. Thus, the inverse synthesis of Ctv and Pnl as a function of temperature is apparently controlled at the transcriptional level, and reduced rdgB expression at 30 degrees C obviously affected transcription from the ctv promoters with low-affinity RdgB boxes. Pathogenicity toward potato tubers was reduced in an rdgB knockout mutant, suggesting that the RdgAB system contributes to the pathogenicity of this bacterium, probably by activating pnl expression.

  7. 产细菌素屎肠球菌E6的特性分析及发酵条件优化%Characteristics and optimization of fermentative condition for bacteriocin producing Enterococcus Faecium E6

    Institute of Scientific and Technical Information of China (English)

    饶瑜; 常伟; 唐洁; 李明元

    2013-01-01

    研究了屎肠球菌E6抑菌活性的生物学特性,并通过响应面法优化其发酵条件.结果表明,屎肠球菌E6产蛋白质类细菌素,能够抑制单增李斯特氏菌、大肠杆菌、金黄色葡萄球菌和枯草芽孢杆菌生长,在pH3.0~7.0条件下有明显抑菌活性,60~121℃热处理20min后仍具有抑菌活性.通过Box-Behnken实验设计优化屎肠球菌E6发酵条件为培养时间36.0h,培养温度31.0℃,培养基pH5.1.在此条件下,发酵上清液抑菌圈直径可达20.17mm,较优化前提高了27.2%.%The characteristics of antimicrobial activity and the fermentative condition of Enterococcus Faecium E6 were discussed.Proteinic bacteriocin produced by E6 showed inhibitory activity against Listeria monocytogenes, Escherichia coli, Staphylococcus aureus and Bacillus subtilis. It showed obviously activity under pH3.0 ~ 7.0 condition.lt was also active when heated at 60~121℃ for 20min. The fermentative condition, optimized by Box-Behnken design,was cultured at pH 5.1,temperature of 31.0℃ for 36.0h.Under this condition,the diameter of inhibition zone reached up to 20.17mm,which increased by 27.2% than optimization before.

  8. 乳酸菌细菌素作为天然生物防腐剂在食品工业中的应用进展%Advances on Application of Bacteriocins Produced by Lactic Acid Bacteria as Natural Bio-preservative in Food Industry

    Institute of Scientific and Technical Information of China (English)

    刘国荣; 李平兰; 王成涛

    2012-01-01

    Bacteriocins were antibacterial activity protein or peptide produced by lactic acid bacteria,and they were identified with great potential as natural food bio-preservative because of their strongly antibacterial activity against food borne pathogens and spoilage organism.In this review,the development of the application of bacteriocin as preservative in food industry was reviewed.The existing problems and future research consideration were pointed out.%乳酸菌细菌素是乳酸菌在代谢过程中合成的天然抑菌多肽或蛋白质,由于其对食品腐败菌和致病菌的强烈抑菌活性,已成为天然食品生物防腐剂研究与开发的热点.对乳酸菌细菌素在食品工业中的应用研究作了全面系统的综述,并指出了目前存在的主要问题和今后的研究方向.

  9. Evaluation of bacteriocin-producing Lactobacillus sakei 1 against Listeria monocytogenes 1/2a growth and haemolytic activity Avaliação de Lactobacillus sakei 1 produtor de bacteriocina frente a Listeria monocytogenes 1/2a e sua atividade hemolítica

    Directory of Open Access Journals (Sweden)

    Rafael C.R. Martinez

    2005-03-01

    Full Text Available Bacteriocin-producing Lactobacillus sakei 1 was cultivated in Brain-Heart Infusion broth (24 h at 25ºC. The culture supernatant was neutralized, filter sterilized and used to test the activity of bacteriocin against Listeria monocytogenes 1/2a, at 8ºC and 15ºC. Non-bacteriocinogenic Lactobacillus sakei ATCC 15521 was used as a negative control. L. monocytogenes 1/2a was inoculated in culture supernatant medium from L. sakei 1 and L. sakei ATCC 15521 and the listerial populations were determined after 0, 5 and 10 days. The bacteriocin production was quantified as arbitrary units per mL (AU/mL using agar antagonism test. Additionally, to investigate if L. monocytogenes virulence pattern could be changed after bactericion exposure, the ability of L. monocytogenes to cause haemolysis in sheep red blood cells was determined, before and after exposure to bacteriocin at 8ºC. In the presence of the antimicrobial peptide, at 8ºC, L. monocytogenes population decreased, but growth of resistant cells was observed. At 15ºC, there was no difference between test and control. Furthermore, the haemolytic activity of L. monocytogenes 1/2a was not altered by exposure to L. sakei 1 bacteriocin, which suggests no change in its virulence pattern.Lactobacillus sakei 1 produtor de bacteriocina foi cultivado em caldo Infusão Cérebro-Coração por 24h a 25ºC. O sobrenadante da cultura foi neutralizado, esterilizado por filtração e usado para testar a atividade da bacteriocina frente a Listeria monocytogenes 1/2a, a 8ºC e 15ºC. Lactobacillus sakei ATCC 15521 não bacteriocinogênico, foi utilizado como controle negativo. L. monocytogenes 1/2a foi inoculada no sobrenadante da cultura de L.sakei 1 e L. sakei ATCC 15521 e as populações listeriais foram determinadas após 0, 5 e 10 dias. A produção de bacteriocina foi quantificada como unidades arbitrárias por mL (UA/mL, utilizando-se o teste de antagonismo em ágar. Adicionalmente, para investigar se o padr

  10. 西藏地区发酵牛乳中产细菌素乳酸菌的筛选及鉴定%Screening and Identification of Bacteriocin-producing Lactic Acid Bacteria from Tibet Fermented Milk Products

    Institute of Scientific and Technical Information of China (English)

    陈芝兰; 田发益; 何建清; 杨爽; 李晓卫; 杨吉霞

    2012-01-01

    从西藏地区藏族传统发酵乳中分离乳酸菌,采用生理生化特性和16S基因序列同源性分析对其进行鉴定,通过双层琼脂平板扩散法筛选具有抑菌活性的菌株。结果表明,共分离37株乳酸菌,其中,乳杆菌属(Lacto-bacillus)35株、明串珠菌属(Leuconostoc)2株;35株乳酸杆菌为Lactobacilluscasei16株、Lactobacillusparacasei7株、Lactobacillusplantarum4株、Lactobacillusfermentum2株、L.delbrueckilsubsp.bulgaricus2株、Lactobacillushelveti—CUS1株、Lactobacillusdiolivorans3株;7株L.casei和L.paracasei的发酵上清液对3株细菌指示菌表现出明显抑制作用,所有菌株对真菌无抑菌活性;在排除有机酸、H2O2等的干扰和经蛋白酶K处理后,初步确定7株乳酸菌发酵上清液中的抑菌物质为细菌素。%Thirty seven lactic acid bacterial strains were isolated from Tibet traditional fermented milk products, and were identified to species level through physiological and biochemical characterization, as well as 16S rRNA se- quence analysis method. The result showed that out of 39 isolates, 37 were assigned to lactobacillus genus, including Lactobacillus casei ( 16 ), Lactobacillus paracasei (7), Lactobacillus plantarum (4), Lactobacillus fermentum (2), L. delbrueckii subsp, bulgaricus (2) , LactobaciUus helveticus ( 1 ) , and Lactobacillus diolivorans (3). Two strains were assigned to Leuconostoc genus. Cell free supernatant of seven L. casei and L. paracasei strains showed significant an- timicrobial activity against 3 indicator pathogenic bacteria. All isolated strains had no antimicrobial activity against fungi. The possibility of organic acid or H2O2 action as antimicrobial components was eliminated by experiments. The antimicrobial components were inferred to be bacteriocin because the antimicrobial activity disappeared after cell free supernatant was treated with Droteinase.

  11. Partial purification and characterization of a novel bacteriocin produced by Lactobacillus pentosus LPEM818%戊糖乳杆菌素pentocin LPEM818的初步纯化及特性研究

    Institute of Scientific and Technical Information of China (English)

    于雷雷; 王超; 施波; 马妙莲; 段慧; 张明

    2013-01-01

    对戊糖乳杆菌(Lactobacillus pentosus)LPEM818所产戊糖乳杆菌素(pentocin) LPEM818进行了初步纯化,并对其生物学特性进行了研究.结果表明,采用80%硫酸铵沉淀和Sephadex G-25凝胶层析分离纯化后,细菌素的纯化倍数为11.09倍,回收率为6.4%;该细菌素在pH 2.0 ~8.0条件下稳定,121℃加热15 min保留84.52%的抑菌活性;对胰蛋白酶和蛋白酶K敏感;该细菌素的作用方式为杀菌;对供试的部分革兰氏阳性菌(G+)和革兰氏阴性菌(G-)具有较强抑制作用,因其抑菌谱较广,对多数致病菌和食品腐败菌有较好抑菌作用,所以具有作为食品生物防腐剂的潜在应用价值.%The partial purification and characterization of pentocin LPEM818 produced by Lactobacillus pentosus LPEM818 were studied.Pentocin LPEM818 was purified by 80 % ammonium sulfate precipitation and Sephadex G-25 column chromatography.The results showed that an 11.09 fold purification and 4.6% yield were obtained.Pentocin LPEM818 exhibited strong heat stability (remained 84.52 % of the antibacterial activity after 15 min at 121 ℃ ) and pH stability (pH 2.0 ~8.0).The activity of pentocin LPEM818 was destroyed after treatment with proteinase K and trypsin.The mode of action of pentocin LPEM818 was bactericidal.Pentocin LPEM818 exhibited inhibitory activity a-gainst part of the Gram-positive bacteria and Gram-negative bacteria.The identified properties of pentocin LPEM818 indicate that it is a novel bacteriocin with potential application as a bio-preservative to improve the safety of food products.

  12. Characteristics and optimization producing conditions of bacteriocin-like from Lactobacillus plantrum%植物乳酸菌类细菌素特性研究及其产生条件的优化

    Institute of Scientific and Technical Information of China (English)

    解俊梅; 文汉

    2011-01-01

    Lactobacillus production of lactic acid bacteria bacteriocin culture conditions was optimized by single factor experiment and orthogonal and its characteristics was analyzed.The results showed that:the best vegetative growth of lactic acid bacteria was a combination of culture conditions at 30℃,initial pH6.0 with inoculum amount of 4%,seed age 12h,anaerobic conditions for 40h.Lactobacillus streptozotocin on Gram-negative bacteria and yeast inhibition optimum culture conditions for the largest combination of the temperature 28℃,initial pH7.0 with inoculum amount of 2%,seed age 10h,anaerobic conditions for 24h.Gram-positive lactic acid bacteria Streptomyces antibacterial effects had the best combination of culture conditions of temperature 28℃,initial pH 6.5 medium,inoculum 1%,seed age 6h,anaerobic conditions for 40h.Without effect of organic acids and hydrogen peroxide,the cell-free liquid culture of Lactobacillus showed high inhibitory activity against gram-positive bacterias,including Bacillus subtilis and Staphyloccocus aureus Rosenbach and gram-negative bacterias,such as Escherichia coli and Salmonella typhimunius,but also inhibited some fungi.Therefore,the inhibitory substance produced by the lactic acid bacteria was assumed bacteriocin-like substance.Lactic acid bacteria showed it was stable to heat,active at low pH,not sensitive to proteinasea and broad antibacterial spectrum.%通过单因素实验和正交实验优化了乳酸菌产乳酸菌素的培养条件并分析了其特性。结果表明:植物性乳酸杆菌生长的最佳培养条件组合是温度30℃,培养基初始pH为6.0,接种量4%,种龄12h,厌氧条件下,培养时间40h;乳酸菌菌素对革兰氏阴性菌和酵母菌的抑菌作用最大的最佳培养条件组合是温度28℃,培养基初始pH为7.0,接种量2%,种龄10h,厌氧条件下,培养时间24h。乳酸菌菌素革兰氏阳性菌的抑菌作用最大的最佳培养条件组合是温度28℃,培养基初始pH为6.5,

  13. 风干肠中戊糖片球菌所产细菌素L5-6的理化特性研究%A Study on Physicochemical Characteristics of Bacteriocin L5-6 Produced by Pediococcus Pentosaceus Isolated from Dried Cured Salami

    Institute of Scientific and Technical Information of China (English)

    张红星; 刘丽; 谢英; 郝彦玲

    2011-01-01

    Objective: In order to develop a kind of safe and effective food bio-preservative, the physicochemical characteristics of bacteriocin L5-6, produced by Pediococcus pentosaceus isolated from dried cured salami, was systematically studied. Methods: Inhibitory activity was analyzed by the well-diffusion method. The molecular weight of the bacteriocin was detected by Tricine-SDS-PAGE. Results: The anti-bacterial substance L5-6, which was found to be sensitive to proteolytic enzymes such as trypsin, proteinase K, and pronase E, was proved to be bacteriocin. Bacteriocin L5-6 had heat stability up to 100 ℃ (30min). Antibacterial activity still remained at pH from 2.0 to 10.0. Its maximum antibacterial activity was 2 560 AU during stationary phase (pH4.20) and the best harvesting time was 18h. Its mode of action was bactericidal with Listeria monocytogenes. Besides, it also exhibited the inhibition against gram-positive bacteria, such as Staphylococcus aureus, Lactobacillus plantarum, Lactobacillus delbrueckii subsp bulgaricus and gram-negative bacteria,such as Escherichia coli, Shigella, Salmonella. Tricine-SDS-PAGE showed that its molecular weight was about 4 kDa.Conclusions: Bacteriocin L5-6 was heat-stable (30 min at 100 ℃) and remained activity after incubation at pH from 2.0 to 10.0. It covered broad antimicrobial spectrum and could be degraded by proteases existing in the human body. Therefore, bacteriocin L5-6 had the potential prospect of application in the field of food preservation.%目的:对从风干肠中筛选的戊糖片球菌所产细茵素L5-6的理化特性进行系统研究,为开发安全高效的食品生物防腐剂奠定理论基础.方法:采用管碟法做抑菌试验,利用N-羟甲基甲基甘氨酸-SDS-PAGE电泳确定细茵素的相对分子质量.结果:抑菌物质L5-6时胰蛋白酶、蛋白酶K、链霉蛋白酶E敏感,证明此押菌物质为细菌素;细菌素L5-6在100℃30 min,pH 2~10的条件下具有极强的抑菌活性;当戊

  14. Isolation and identification of lactic acid bacteria producing anti-Staphylococcus aureus bacteriocin%分泌抗金黄色葡萄球菌细菌素乳酸菌的分离鉴定

    Institute of Scientific and Technical Information of China (English)

    王全溪; 许丽惠; 邓红玉; 吴雪珍; 庄育彬

    2014-01-01

    为分离和筛选产抗金黄色葡萄球菌乳酸菌素的优势乳酸菌,利用乳酸菌分离培养基MRS从收集的各种腌制菜汁中分离培养乳酸菌,通过细菌培养特性、革兰氏染色特点、生理生化特性初步鉴定,同时根据Genbank中乳酸菌的16S rDNA 序列设计特异性引物,采用PCR方法进一步鉴定,并以金黄色葡萄球菌为指示菌对乳酸菌的发酵上清液进行抑菌特性研究。结果表明,从腌渍菜汁中分离获得90株产酸菌,通过形态学、生理生化特性和PCR鉴定,结果73株产酸菌为乳酸杆菌;分泌产物抑菌试验表明,有10株菌具有抑制金黄色葡萄球菌活性,经酸排除和过氧化氢排除试验,仍然有5株乳酸菌的分泌产物具有抑制金黄色葡萄球菌活性。可见,从腌渍菜汁分离到的乳酸菌具有抑制金黄色葡萄球菌活性的特性,主要是通过分泌乳酸菌素来发挥作用。%The study was carried out to separate the lactic acid bacteria which could produce the bacteriocin against S.aureus. In this experiment, the lactic acid bacteria were isolated from the salted and preserved vegetables with the MRS medium. Identification was done by bacterial culture characteristics, Gram stain characteristics, physiological and biochemical characterization, And the bacteria was identified by PCR. The antibacterial properties of lactic acid bacteria fermentation supernatant was studied. The results showed that 73 strains acid-producing bacteria were isolated, and were identified to Lactobacillus by morphological characteristics, biochemi-cal characteristics and PCR. The antibacterial test showed that there were ten strains Lactobacillus which secretory products could in-hibit staphylococcus aureus. Ruled out by acid and hydrogen peroxide exclusion experiments, there were still 5 strains of lactic acid bacteria which secretion can inhibit staphylococcus aureus. Therefore, in this experiment the lactic acid

  15. Paracin 1.7, a bacteriocin produced by Lactobadllus paracasei HD1.7 isolated from Chinese cabbage sauerkraut, a traditional Chinese fermented vegetable food%细菌素Paracin 1.7的纯化与性质

    Institute of Scientific and Technical Information of China (English)

    葛菁萍; 平文祥; 宋刚; 杜春梅; 凌宏志; 孙欣; 高莹

    2009-01-01

    [Objects] To purify and characterize bacteriocin produced by L. paracasei HD1.7. [Methods] Paracin 1.7 was purified by chromatography and its molecular weight was measured by using sodium dodecyl sulfate -polyacrylamide gel electrophoresis (SDS-PAGE). Antibacterial activity was measured by using the agar-well diffusion method. [Results] The bacterial strain for the fermentation was identified as Lactobacillus subsp. paracasei. Paracin 1.7 had the activity of inhibiting the growth of other bacteria. Maximum production of Paracin 1.7 was in the stationary phase. Paracin 1.7 can be well purified with Cation exchange chromatography,Sephedex (G5O,G25,G10) gel chromatography and high performance liquid chromatography (HPLC) on C18 column and its determined molecular weight was about 11 kDa by Tricine-SDS-PAGE. Paracin 1.7 shows a broad spectrum of activities against various strains in the genera of Proteus, Bacillus, Enterobacter, Staphylococcus, Escherichia, Lactobacillus, Microccus , Pseudomonas , Salmonella and Saccharomyces , some of which belong to food borne pathogenic bacteria. Although Paracin 1.7 displayed stability toward heat and acidic pH, it was sensitive to several proteolytic enzymes. The inhibitory activities remain well after stored at 4℃ for 4 months; the inhibitory activity declined only 4.19% . [Conclusion] Paracin 1.7 can be a potential food preservative on the basis of its antibacterial characters.%[目的]分离纯化(Lactobacillus paracasei)HD1.7所产生的细菌素并分析其特性.[方法]细菌素Paracin1.7的纯化采用色谱技术,其分子量检测采用十二烷基磺酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE),利用琼脂扩散法测定细菌素活力.[结果]Paracin 1.7分离于我国传统发酵食品酸菜发酵液中,其产生菌为副干酪乳杆菌.Paracin 1.7可以抑制其它微生物的生长,为细菌素.该菌在稳定期可产生大量Paracin 1.7.经过阳离子交换层析、凝胶过滤层析以及高效液相色

  16. 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

    Directory of Open Access Journals (Sweden)

    Ângela M. Fiorentini

    2001-03-01

    Full Text Available 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 performed on meat cubes after 0, 3, 6, 9, 12 and 15 days. These determinations were also done in cubes dipped in a 6% lactic acid solution (treatment B and distilled water (treatment C. After 3 days, the counts of psychrotrophic microorganisms in cubes submitted to treatment A, B and C increased 0.38, 1.42 and 2.04 log cycles, respectively. The same happened with mesophilic microorganisms (0.31, 0.33 and 1.04 log cycles increases, respectively. On the sixth day, the psychrotrophic population in samples submitted to treatments A and B were 2.07 and 0.64 log cycles, respectively, lower than in the control samples (treatment C. Mesophilic microorganisms in these samples were 1.58 and 1.12 log cycles, respectively, lower than the controls. On the sixth day, only samples submitted to treatment A presented lower counts than those recommended by ICMSF as quality standards for raw meat (Melaço de cana de açúcar é um sub-produto barato da indústria açucareira. Esse produto foi empregado para o crescimento e produção de bacteriocina de Lactobacillus plantarum BN e avaliado quando a sua aplicação potencial no aumento da vida útil de carne crua. Cubos de carne bovina foram imersos por 5 minutos no sobrenadante filtrado e neutralizado dessa cultura (Tratamento A e mantidos a 5ºC. Contagens de microrganismos psicrotróficos e mesófilos, determinação de pH e de acidez total foram realizadas nas amostras após 0, 3, 6, 9, 12 e 15 dias. Essas determinações foram

  17. Inhibition of Listeria monocytogenes growth by using combined bacteriocin-producing strains in raw beef%产抗菌素乳酸菌的组合应用对牛肉中李斯特菌污染的抑制作用研究

    Institute of Scientific and Technical Information of China (English)

    张佩华; 谷贵章; 张进杰; 陈健初

    2011-01-01

    The synergy inhibition of two lactic acid bacteria strains, Lactobacillus curvatus and Pediococcus acidilactici H,on the growth of Listeria monocytogenes in frozen beef was investigated. A Lactobacillus curvatus strain( producing the bacteriocin sakacin P)and a Pediococcus acidilactici H (producing bacteriocin pediocin AcH)were inoculated alone or together in a Listeria-seeded raw pork meat which was stored at 4℃ for 6 weeks.The growth of Listeria monocytogenes was controlled by adding either LAB strain alone,yet the rebound appeared after one-week storage. However,the time of inhibition was prolonged by adding combined these two LAB strains to 6 weeks, after when the Listeria monocytogenes had a rebound with the cfu count lower than 10cfu · g-1.Therefore, using the combined these two LAB strains can effectively delay the rebound of Listeria monocytogenes in the beef.%研究了弯曲乳酸杆菌和乳酸片球菌对低温冷藏牛肉中李斯特菌的混合协同抑制作用.李斯特菌、弯曲乳酸杆菌(产细菌素sakacin P)和乳酸片球菌(产生片球菌素AcH),单独或混合接种于冷鲜牛肉中,4℃下储藏6周.单一接种弯曲乳酸杆菌或乳酸片球菌均能对李斯特菌起到抑制作用,但一周后均出现李斯特菌再次污染现象;然而混合接种弯曲乳酸杆菌和乳酸片球菌能将对李斯特菌的抑制期延长至第六周,之后才出现反弹现象,且李斯特菌数低于10cfu·g-1.因此,应用组合产细菌素菌株能有效延长对李斯特菌的抑制作用.

  18. Isolation of bacteriocin-producing lactic acid bacteria from meat and meat products and its spectrum of inhibitory activity Isolamento de bactérias lácticas produtoras de bacteriocinas a partir de carnes e produtos cárneos e seu espectro de atividade inibitória

    Directory of Open Access Journals (Sweden)

    Renata Bromberg

    2004-06-01

    Full Text Available A total of 285 samples of meat and meat products were evaluated for the presence of bacteriocin-producing lactic acid bacteria by the "sandwich" test. From 174 of these samples, 813 strains of lactic acid bacteria were isolated. They were able to inhibit the growth of Staphylococcus aureus CTC 33 and/or Listeria innocua Lin 11. When evaluated by the well-diffusion assay, 128 of these strains inhibited the growth of the indicator strains. The inhibitory spectra of activity of the isolates were evaluated against a range of Gram-positive and Gram-negative test organisms. S. aureus was the most sensitive indicator tested, whereas Enterococcus faecalis and Lactobacillus plantarum were the most resistant ones. All the compounds produced by the lactic acid bacteria were fully or partially inactivated by some of the proteolytic enzymes, which indicates their proteinaceous nature. The antimicrobial activity of the bacteriocins produced by the lactic acid bacteria isolated in this work could act as a potential barrier to inhibit the growth of spoilage bacteria and foodborne pathogens.Um total de 285 amostras de carnes e produtos cárneos foi avaliado para detecção de culturas produtoras de bacteriocinas pelo método do "sanduíche". A partir de 174 destas amostras, 813 linhagens de bactérias lácticas com atividade inibitória sobre Staphylococcus aureus CTC 033 e/ou Listeria innocua Lin 11 foram isoladas. Quando examinadas pelo método de antagonismo simultâneo em poços, 128 destas linhagens inibiram o crescimento dos microrganismos indicadores. O espectro de atividade das linhagens isoladas foi avaliado com diversos microrganismos Gram-positivos e Gram-negativos. De um modo geral, S. aureus foi o microrganismo indicador mais sensível, enquanto Enterococcus faecalis e Lactobacillus plantarum foram os mais resistentes. Todos os compostos antimicrobianos produzidos pelas bactérias lácticas testadas foram completa ou parcialmente inativados por

  19. Screening of Broad-spectrum Bacteriocin-producing Lactic Acid Bacteria Strain and Characteristics of Antibacterial Compounds%1株产广谱细菌素乳酸菌的筛选及其抑菌物质的特性

    Institute of Scientific and Technical Information of China (English)

    曹珂珂; 王娣; 李妍

    2012-01-01

    By A broad spectrum bacteriocin producing strain was screened by plant punching and its antibacterial characteristics was studied. The results showed that one baeteriocin-producing Lactic acid bacteria strain isolated from plant materials exhibited strong inhibition activity against the E. coil. The supernatant of this strain could still inhibit the growth of indicator strain strongly after eliminating hydrogen peroxide and organic acid. After treatment with pep- sin, the strain' s inhibitory activity decreased sharply, which showed the inhibitory substance possessed the character- istic of protein, and it could be named bacterioein. The strain was identified as Laetobacillus plantarum through detec- tion of its appearance, physiological and biochemical characteristics. The inhibitory activity of strain fermentation su- pernatant was not affected by high temperature, 1% Tween-80, SDS, EDTA and the low pH. However, its inhibitory activity revealed an obvious decrease after treatment with protease K and trypsin than with pepsin. The bacterial inhi- bition spectrum showed that this was a kind of bacteriocin with wide inhibition soectrum.%从植物性材料中筛选到1株对大肠杆菌有明显抑制作用的乳酸菌,在排除有机酸和过氧化氢的干扰后,该菌株的发酵上清液仍有较强的抑菌性;胃蛋白酶处理后,抑菌活性明显降低,说明其抑菌物质为蛋白质类物质,是一种细菌素。通过形态学和生理生化分析,初步鉴定该菌株为植物乳杆菌。生物学特性研究表明,该菌株发酵上清液经高温、吐温-80、SDS、EDTA处理后,仍保持较好的抑菌活性;在酸性条件下稳定;对蛋白酶K和胰蛋白酶较胃蛋白酶敏感。抑菌谱显示,该菌株的发酵上清液具有广谱抑菌性。

  20. Isolation and Identification of a Bacillus Strain with Bacteriostatic Ability and Detection on Its Characters of Producing Bacteriocin%一株抑菌芽胞杆菌的分离鉴定及产细菌素性能检测

    Institute of Scientific and Technical Information of China (English)

    辛国芹; 徐海燕; 武香玉; 汪孟娟; 谢全喜; 谷巍

    2012-01-01

    A strain BX-6 with good bacteriostatic activity was isolated from fresh chicken manure by routine microbiological method. Based on the means of colony morphological characteristics, physiological and biochemical characteristics and 16S rDNA sequence phylogeny analysis, the strain was identified and classified. And the antimicrobial characters of bacteriocin produced by BX-6 was detected by cylinder-plate method. The results showed that strain BX-6 was identified as Bacillus subtilis. Some antibacterial substance of H202 was produced in the fermentation process of BX-6. The bacteriocin had a good thermal stability,pH tolerance and it was sensitive to most proteases. And it had better antibacterial effects on Salmonella pullorum C79-13 ,chicken Escherichia coil O1 and Staphylococcus aureus C56011. So it had the potential to be used as feed additive of livestock and poultry.%采用常规微生物学方法从新鲜鸡粪中分离得到1株抑菌效果较好的菌株BX-6。结合菌落形态特征、生理生化特性及菌株特异性序列分析等手段,确定其分类归属,并采用管碟法对所产细菌素的抑菌特性进行了检测。结果表明,菌株BX-6为枯草芽胞杆菌(Bacillus subtilis)。菌株在发酵过程中产生一定量的H2O2类抑菌物质,其所产细菌素具有较好的热稳定性、pH值耐受性,对大部分蛋白酶敏感,对鸡白痢沙门氏菌C79—13、鸡大肠杆菌01和金黄色葡萄球菌C56011有较好的抑菌效果,具有作为畜禽饲料添加剂的潜力。

  1. Construction of Lactobacillus plantarum ⅡD gene mutant and its sensitive analysis for class Ⅱa bacteriocin%植物乳杆菌ⅡD基因突变株的构建及对Ⅱa类细菌素敏感性分析

    Institute of Scientific and Technical Information of China (English)

    熊尧; 谢英; 张世湘; 张列兵; 罗云波; 郝彦玲

    2013-01-01

    The mannose phosphotransferase system IID mutant of L. plantarum WQ0815 has been constructed by homologous recombination technology, which is sensitive to plantaricin LB-B1. The sensitivity of mutants to plantaricin LB-Bl was determined by the well-diffusion assay, which showed that interruption of IID gene led to resistance of L. plantarum WQ0815 against class Ila bacteriocin. These results showed that the IID component of sensitive strain is direcdy involved in the recognition of the target cell by class Ila plataricin LB-B1.%采用同源重组技术,对Ⅱa类植物乳杆菌素LB-B1敏感的植物乳杆菌WQ0815中甘露糖磷酸转移酶系统(Ell.Man)中的 ⅡD组分进行突变,利用牛津杯法分析了植物乳杆菌WQ0815 ⅡD组分突变前后对植物乳杆菌素LB-B1的敏感性变化.结果表明,突变株对植物乳杆菌素LB-B1产生抗性,说明敏感菌株中Ell.Man的 ⅡD组分是植物乳杆菌素LB-B1发挥抑茵作用时的结合位点.

  2. 苏云金芽胞杆菌BRC-ZYR2一个假定的细菌素基因AOI-3的鉴定及异源表达%Identification and Heterologous Expression of A Putative Bacteriocin Gene AOI-3 from Bacillus thuringiensis BRC-ZYR2

    Institute of Scientific and Technical Information of China (English)

    苏小玉; 林丽鹏; 骆祥银; 李仪莹; 戴瑞卿; 潘洁茹; 黄天培

    2015-01-01

    细菌素(Bacteriocin)是由某些细菌通过核糖体途径产生的一类具有抗菌活性的多肽或蛋白质,因其无致畸变作用,也不易产生耐药性,在食品及卫生安全中备受关注.本研究以经过全基因组测序的苏云金芽胞杆菌(Bacillus thuringiensis,Bt) BRC-ZYR2为出发菌株,预测得到一个假定的细菌素基因AOI-3.PCR扩增获得231 bp目的基因片段,利用无缝克隆技术将目的基因片段连接到pET32a载体,转入大肠杆菌(Escherichia coli)JM 109,筛选克隆子进行酶切以及测序验证.基因序列比对结果显示,该基因与Bt HD-789全基因组中一段未被注释的核酸序列(GenBank登录号:CP003763.1)同源性达99%.氨基酸序列比对结果显示,与一个假定的Bt细菌素(Bt bacteriocin biosynthesis protein)(GenBank登录号:WP 033699510.1)的同源性达100%.此外,该细菌素的保守结构域属于未知功能域家族蛋白(domain of unknown function,DUF)亚族蛋白DUF2762,可能具有类似穿孔毒素Bh1A的作用.氨基酸组成分析表明,该基因序列编码76个氨基酸,分子量为8 813.62 Da,等电点为4.82,无信号肽,含有1个跨膜区,将重组表达载体转入大肠杆菌BL21(DE3),异丙基-β-D-硫代吡喃半乳糖苷(isopropyl-β-D-1-thiogalactopyranoside,IPTG)诱导表达.十二烷基硫酸钠聚丙烯酰胺凝胶电泳(sodium dodecyl sulfate polyacrylamide gel electrophoresis,SDS-PAGE)结果表明,在上清中检测到预期的8.8kD多肽表达.采用His-tag亲和层析技术纯化目的蛋白.本研究通过对假定的细菌素基因AOI-3克隆、表达和获得多肽纯品,为测定其抑菌谱并了解细菌素结构及作用机理奠定了基础.

  3. Comparison of two methods for purification of plantaricin ST31, a bacteriocin produced by Lactobacillus plantarum ST31 Comparação de dois métodos de purificação da plantaricina ST31, a bacteriocina produzida por Lactobacillus plantarum ST31

    Directory of Open Access Journals (Sweden)

    Svetoslav D. Todorov

    2004-06-01

    Full Text Available Two methods of purification of the plantaricin ST31, a bacteriocin produced by Lactobacillus plantarum ST31 are used in this study - the method of ammonium sulfate precipitation, Sep-pack C18 cartridge and reverse-phase HPLC chromatography on C18 Nucleosil column, and the method of direct purification by cation exchange SP Sepharose Fast Flow column Amersham (Pharmacia Biotech. The purity of the products from the two experimental protocols are examined for their molecular weight, aminoacid composition and sequence. Comparison of results show that the plantaricins purified with the two methods are identical. Both methods may be used to purify plantaricin ST31. Comparison of the yield in the purification protocols is 0.8% in the HPLC experimental protocol and 5.9% in the cation-exchange chromatography method.Dois métodos de purificação de plantaricin ST31, uma bacteriocina produzida por Lactobacillus plantarum ST31 foram usados neste estudo - o método de precipitação pelo sulfato de amônia usando cartucho Sep-pack C18 para a filtração e HPLC de fase reversa em coluna de C18 Nucleosil, e o método de purificação direta por troca catiônica SP Sepharose "Fast Flow column Amersham" (Pharmacia Biotech. A pureza dos produtos obtidos pelos dois protocolos foi examinada através da determinação dos pesos moleculares, composição e seqüência dos aminoácidos. A comparação destes resultados revelou que, em termos da pureza dos produtos, não havia diferenças entre os dois métodos de purificação podendo-se, portanto, utilizar qualquer um dos protocolos de purificação testados. No entanto, o rendimento da purificação pelo método da troca catiônica foi de 5.9% enquanto o do método HPLC foi de 0.8%.

  4. A peptide factor secreted by Staphylococcus pseudintermedius exhibits properties of both bacteriocins and virulence factors

    NARCIS (Netherlands)

    Wladyka, Benedykt; Piejko, Marcin; Bzowska, Monika; Pieta, Piotr; Krzysik, Monika; Mazurek, Lukasz; Guevara-Lora, Ibeth; Bukowski, Michal; Sabat, Artur J.; Friedrich, Alexander W.; Bonar, Emilia; Miedzobrodzki, Jacek; Dubin, Adam; Mak, Pawel

    2015-01-01

    Staphylococcus pseudintermedius is a common commensal bacterium colonizing the skin and mucosal surfaces of household animals. However, it has recently emerged as a dangerous opportunistic pathogen, comparable to S. aureus for humans. The epidemiological situation is further complicated by the incre

  5. Bacteriocins of food grade lactic acid bacteria in hurdle technology for milk and dairy

    Science.gov (United States)

    The use of high temperature/short time (HTST) pasteurization has proven effective in eliminating microbial contaminants from raw milk; however some thermoduric bacteria and spore-formers have been reported to survive pasteurization at low numbers. Furthermore, improper pasteurization, post-pasteuri...

  6. Thermophilin 13, a nontypical antilisterial poration complex bacteriocin, that functions without a receptor

    NARCIS (Netherlands)

    Marciset, O.; Jeronimus-Stratingh, C.M; Mollet, B.; Poolman, B.

    1997-01-01

    A novel broad host range antimicrobial substance, Thermophilin 13, has been isolated and purified from the growth medium of Streptococcus thermophilus. Thermophilin 13 is composed of the antibacterial peptide ThmA (M-r of 5776) and the enhancing factor ThmB (M-r of 3910); the latter peptide increase

  7. Functional analysis of circular and linear bacteriocins of Gram-positive bacteria

    NARCIS (Netherlands)

    Kemperman, Robèr Antoine

    2005-01-01

    SUMMARY & GENERAL DISCUSSION Preservation methods such as drying and fermenting to store food products for longer periods of time have been used for centuries. Nowadays, people desire fresh and minimally processed food, to be prepared with minimal cooking. This sets new targets for the food industry

  8. Genome sequence of the lantibiotic bacteriocin producer Streptococcus salivarius strain K12.

    Science.gov (United States)

    Barretto, Caroline; Alvarez-Martin, Pablo; Foata, Francis; Renault, Pierre; Berger, Bernard

    2012-11-01

    Streptococcus salivarius is a prevalent commensal species of the oropharyngeal tract. S. salivarius strain K12 is an isolate from the saliva of a healthy child, used as an oral probiotic. Here, we report its genome sequence, i.e., the full sequence of the 190-kb megaplasmid pSsal-K12 and a high-quality draft 2.2-Gb chromosomal sequence. PMID:23045482

  9. Cloning and optimization of a nisin biosynthesis pathway for bacteriocin harvest.

    Science.gov (United States)

    Kong, Wentao; Lu, Ting

    2014-07-18

    Nisin is an important antimicrobial peptide that has enormous applications in biotechnology. Despite many encouraging efforts, its overproduction has been a long-standing challenge due to the complexity of the underlying pathway and the difficulty in genetic modification of lactic acid bacteria. Here, we cloned an entire nisin biosynthesis pathway from a nisin-producing strain (Lactococcus lactis K29) into a plasmid and transplanted the plasmid into a nisin deficient strain Lactococcus lactis MG1363, resulting in successful heterologous expression of bioactive recombinant nisin. To increase nisin harvest, we also overexpressed nisA, a gene responsible for nisin precursor production, with a set of constitutive promoters. To further optimize nisin yield, we minimized the metabolic cost of the engineered strains by integrating nisA overexpression cassettes and the recombinant pathway into a single circuit. With our rational construction and optimization, our engineered optimized strain is able to produce bioactive nisin with a yield of 1098 IU/mL, which is more than six times higher than that of the original strain.

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

    OpenAIRE

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

    2011-01-01

    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 h...

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

    OpenAIRE

    Deepansh Sharma; Baljeet Singh Saharan

    2014-01-01

    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 wer...

  12. A spatial model of the evolution of quorum sensing regulating bacteriocin production

    NARCIS (Netherlands)

    Czaran, T.L.; Hoekstra, R.F.

    2007-01-01

    Like any form of cooperative behavior, quorum sensing (QS) in bacteria is potentially vulnerable to cheating, the occurrence of individuals that contribute less but still profit from the benefits provided by others. In this paper, we explore the evolutionary stability of QS as a regulatory mechanism

  13. Diffusion of Fluorescently Labeled Bacteriocin from Edible Nanomaterials and Embedded Nano-Bioactive Coatings.

    Science.gov (United States)

    Imran, Muhammad; Revol-Junelles, Anne-Marie; Francius, Grégory; Desobry, Stéphane

    2016-08-24

    Application of nano-biotechnology to improve the controlled release of drugs or functional agents is widely anticipated to transform the biomedical, pharmaceutical, and food safety trends. The purpose of the current study was to assess and compare the release rates of fluorescently labeled antimicrobial peptide nisin (lantibiotic/biopreservative) from liposomal nanocarriers. The elevated temperature, high electrostatic attraction between anionic bilayers and cationic nisin, larger size, and higher encapsulation efficiency resulted in rapid and elevated release through pore formation. However, acidic pH and optimal ethanol concentration in food simulating liquid (FSL) improved the stability and retention capacity of loaded drug. Thus, controlling various factors had provided partition coefficient K values from 0.23 to 8.78 indicating variation in nisin affinity toward encapsulating macromolecule or FSL. Interaction between nisin and nanoscale bilayer systems by atomic force (AFM) and transmission electron microscopy demonstrated membrane activity of nisin from adsorption and aggregation to pore formation. Novel nanoactive films with preloaded nanoliposomes embedded in biodegradable polymer revealed improved morphological, topographic, and roughness parameters studied by confocal microscopy and AFM. Pre-encapsulated nanoactive biopolymer demonstrated excellent retention capacity as drug carriers by decreasing the partition coefficient value from 1.8 to 0.66 (∼30%) due to improved stability of nanoliposomes embedded in biopolymer network. PMID:27468125

  14. 从虎皮鹦鹉粪便中分离产细菌素菌株及其细菌素特性分析%Characteristics of Bacteriocin and Bacteriocin-producing Bacteria Isolated from Melopsittacus undulates' Excrement

    Institute of Scientific and Technical Information of China (English)

    陈新练; 陈仪本

    2010-01-01

    从虎皮鹦鹉(Melopsittacus undulatus)的粪便中分离得到一株产广谱细菌素的菌株,其细菌素产物时革兰氏阳性和阴性细菌均有较强抑制作用.经形态学、生理生化反应和16S rDNA分子方法鉴定,该菌株初步鉴定为干酪乳杆菌.用硫酸铵分级沉淀得到的细菌素粗提物,作温度、pH值、蛋白酶的敏感性测定,结果显示该细菌素经100℃处理10 min抑菌活性不变,当pH4.0时,对大肠杆菌和金黄色葡萄球菌的抑菌率分别达到99.06%和86.14%,并且对多种蛋白酶表现出敏感性.与Nisin标准品的抑菌效价对比,得到粗提物的效价为204.87 IU/mL.

  15. 肉源产广谱细菌素乳酸菌的筛选及其细菌素特性研究%Screening of broadspectrum bacteriocin-producing lactic acid bacteria from meat and characterization of the bacteriocin

    Institute of Scientific and Technical Information of China (English)

    敖灵; 冯敏; 刘书亮; 刘冬香

    2008-01-01

    从四川腊肉、香肠中分离的91株乳酸菌,经过打孔法初筛、牛津杯法复筛(排除酸、过氧化氢干扰以及胰蛋白酶、木瓜蛋白酶处理)得到1株广谱细菌素产生菌C50-6,经鉴定为戊糖乳杆菌(Lactobacillus pentosus).研究了该菌株产细菌素的最适培养条件为:MRS培养基起始pH6.0,30℃静置培养36h;该细菌素具有较好的热稳定性;显示活性pH值范围为2.0~4.5;对胰蛋白酶和木瓜蛋白酶敏感,而对蛋白酶K和胃蛋白酶敏感性差.

  16. 产细菌素乳酸菌的筛选及其纯化和稳定性研究%Screening bacteriocin-producing lactic acid bacteria and purification of bacteriocin and its stability

    Institute of Scientific and Technical Information of China (English)

    陈沛; 王雪青; 阮海华

    2011-01-01

    以大肠杆菌、金黄色葡萄球菌、藤黄微球菌、单增李斯特菌、枯草芽孢杆菌、志贺氏菌、沙门氏菌为指示菌,从30个健康婴儿的粪便中筛选得到1株具有广谱抑菌作用的菌株,经鉴定为乳酸乳球菌(编号F-6-B).该菌株的培养条件为:MRS培养基起始pH 6.0,30℃静置培养48 h.将其发酵液经硫酸铵沉淀,Hitrap SPHP(GE)阳离子交换柱层析后,得到的样品通过Tricine-SDS-PAGE为一条带,相对分子质量为3 300~5 800之间.经不同酸、热处理,该细菌素仍具有较好的抑菌活性,表现出较好的热稳定性和广谱的活性pH值范围,对胰蛋白酶处理敏感性差.

  17. Elongated cells of Listeria monocytogenes in biofilms in the presence of sucrose and bacteriocin-producing Leuconostoc mesenteroides A11

    Directory of Open Access Journals (Sweden)

    Regiane Priscilla Ratti

    2010-12-01

    Full Text Available Listeria monocytogenes is a foodborne pathogen which may survive in biofilms and persist in food processing plants. In this study, the ability of Leuconostoc mesenteroides (bac+ and bac- to inhibit biofilm formation by L. monocytogenes ATCC 19115 was studied with stainless steel coupons immersed in BHI broth and BHI broth plus sucrose in combination with the Lactic Acid Bacteria (LAB. Adhered cells were collected with swabs and enumerated on selective agars (Oxford for listeria and MRS for leuconostoc. Leuconostoc mesenteroides bac+ in co-culture with L. monocytogenes was effective to inhibit biofilm formation by listeria for up to 3 hours of incubation, but at 24 hours, biofilm was present in all conditions tested, as confirmed by observations of stainless steel coupons under Scanning Electron Microscopy (SEM. It was also observed that in the presence of L. mesenteroides bac+ in BHI plus sucrose, a high number of elongated cells of L. monocytogenes was present, which may indicate an adaptation response of the pathogen to stress conditions with important implications for food safety.

  18. 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

  19. The activity and stability of cell associated activity of bovicin HC5, a bacteriocin from Streptococcus bovis HC5

    Science.gov (United States)

    Streptococcus bovis HC5 cultures released a broad spectrum lantibiotic, bovicin HC5, into the cell-fee culture supernatant after they reached stationary phase, but most of the antibacterial activity remained cell-associated. Cell-associated bovicin HC5 was more resistant to degradation by Pronase E ...

  20. Purification and characterization of thermophilin T, a novel bacteriocin produced by Streptococcus thermophilus ACA-DC 0040

    NARCIS (Netherlands)

    Aktypis, A.; Kalantzopoulos, G.; Huis Veld,in't J.H.J.; Brink, B. ten

    1998-01-01

    ACA-DC 0040 produced an antimicrobial agent, which was named thermophilin T, active against several lactic acid bacteria strains of different species and food spoilage bacteria, such as Clostridium sporogenes C22/10 and Cl. tyrobutyricum NCDO-1754. The crude antimicrobial compound is sensitive to pr

  1. Immunity to the Bacteriocin Sublancin 168 Is Determined by the SunI (YolF) Protein of Bacillus subtilis

    NARCIS (Netherlands)

    Dubois, Jean-Yves F.; Kouwen, Thijs R. H. M.; Schurich, Anna K. C.; Reis, Carlos R.; Ensing, Hendrik T.; Trip, Erik N.; Zweers, Jessica C.; van Dijl, Jan Maarten

    2009-01-01

    Bacillus subtilis strain 168 produces the extremely stable lantibiotic sublancin 168, which has a broad spectrum of bactericidal activity. Both sublancin 168 production and producer immunity are determined by the SP beta prophage. While the sunA and sunT genes for sublancin 168 production have been

  2. Functional analysis of the gene cluster involved in production of the bacteriocin circularin A by Clostridium beijerinckii ATCC 25752

    NARCIS (Netherlands)

    Kemperman, R; Jonker, M; Nauta, A; Kuipers, OP; Kok, J

    2003-01-01

    A region of 12 kb flanking the structural gene of the cyclic antibacterial peptide circularin A of Clostridium beijerinckii ATCC 25752 was sequenced, and the putative proteins involved in the production and secretion of circularin A were identified. The genes are tightly organized in overlapping ope

  3. 天然食品防腐剂——细菌素%The Natural Food Preservatives——Bacteriocins

    Institute of Scientific and Technical Information of China (English)

    史沁红; 李青

    2008-01-01

    细菌素是一类安全、高效、无毒的天然食品防腐剂.本文介绍了细菌素的分类,以及细菌素与抗生素的区别,以尼生素,纳他霉素为重点阐述了细菌素的抑菌机理及在肉制品中的应用.

  4. Inactivating Methicillin Resistant Staphylococcus aureus (MRSA) and Other Pathogens by Bacteriocins OR-7 and E 50-52.

    Science.gov (United States)

    Worldwide, reports document the increasing frequency of methicillin resistant Staphylococcus aureus (MRSA) infections. Other human pathogens are recognized as unresponsive to antibiotics of last resort. These previously treatable infections now account for increased numbers of human disease and de...

  5. Les bactériocines des bactéries lactiques : caractéristiques et intérêts pour la bioconservation des produits alimentaires

    OpenAIRE

    Dortu C.; Thonart P.

    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 ...

  6. The characterization and application of bacteriocins from lactic acid bacteria%乳酸菌素的特性及应用

    Institute of Scientific and Technical Information of China (English)

    宁喜斌

    2002-01-01

    @@ 乳酸菌素是从一般认为安全的乳酸菌产生的,这引起了人们极大的兴趣,通过它来控制食品中的某些腐败菌和病原菌.特别是乳酸菌产生的细菌素对单核细胞增生李斯特氏菌(Listeria monocytogenes)具有抑菌特性.乳酸菌素是具有生物活性的蛋白质,它对其它相近种类的细菌具有抑制作用,乳酸菌素一般是带正电荷的小分子蛋白(30~60个氨基酸残基),具有高等电点和亲水特性[1].以前的研究主要集中于纯化,氨基酸顺序测定,遗传因子的描述等.而对它们作用机制所知甚少.根据Nettles和Barefoot的报道乳酸菌素中约三分之二没有深入研究[2].

  7. Antimicrobial activity and the presence of virulence factors and bacteriocin structural genes in Enterococcus faecium CM33 isolated from ewe colostrum

    Directory of Open Access Journals (Sweden)

    YOUSEF eNAMI

    2015-07-01

    Full Text Available AbstractScreening of lactic acid bacteria isolated from ewe colostrum led to the identification and isolation of Enterococcus faecium CM33 with interesting features, such as high-survival rates under acidic or bile salt conditions, high tolerance to the simulated gastrointestinal condition, and high adhesive potential to Caco-2 cells. According to the inhibition of pathogen adhesion test results, this strain could reduce more than 50% adhesion capacity of Escherichia coli, Shigella flexneri, Klebsiella pneumoniae, Listeria monocytogenes, and Staphylococcus aureus to Caco-2 cells. Based on the antibiotic sensitivity test findings, E. faecium CM33 was susceptible to gentamycin, vancomycin, erythromycin, ampicillin, penicillin, tetracycline, and rifampicin, but resistant to chloramphenicol, clindamycin, and kanamycin. Upon the assessment of the virulence determinants for E. faecium CM33, this strain was negative for all tested virulence genes. Furthermore, the genome of this strain was evaluated for the incidence of the known enterocin genes by specific PCR amplification, and the genes encoding enterocins A, 31, X, and Q were discovered. The findings of this study showed that the strain E. faecium CM33 could be considered a valuable nutraceutical, and it can be introduced as a new potential probiotic.

  8. Separation of a Bacteriocin-Producing Lactic Acid Bacteria Strain from Pickles%泡菜中产细菌素的乳酸茵分离研究

    Institute of Scientific and Technical Information of China (English)

    胡杨; 项松涛; 杨宇清; 郑一敏; 王琳琳; 胥秀英; 曾品涛; 李杰

    2012-01-01

    实验从泡菜中分离出一株有抑制革兰氏阳性细菌、革兰氏阴性细菌作用的菌株,经鉴定为乳酸菌中的肠膜明串殊菌,该抗菌物质对蛋白水解酶敏感,耐热并在较宽的pH值范围内保持活性。在排除是有机酸和过氧化氢后,初步认为该菌产生的抗菌物质为抗菌肽,即细菌素。%A lactic acid bacteria strain was isolated from traditional food pickles. It was identified to be Leuconostoc mesenteroides. The strain was found to produce an extracellular antimicrobial substance that was peptide in nature (bacteriocin) and effective against Gram-positive bacteria and Gram-negative bacteri- a. The antimicrobial peptide was assayed as non-organic acid and non-hydrogen peroxide and sensitive to proteolytic enzymes, resistant to heat and active over a wide range of pH.

  9. The effect of ingestion of milk supplemented with salivaricin A-producing Streptococcus salivarius on the bacteriocin-like inhibitory activity of streptococcal populations on the tongue.

    Science.gov (United States)

    Dierksen, Karen P; Moore, Chris J; Inglis, Megan; Wescombe, Philip A; Tagg, John R

    2007-03-01

    The colonization efficacies of salivaricin A (SalA)-producing Streptococcus salivarius strains 20P3 and 5 were compared when given in milk to 219 children, using either 2-day or 9-day dosing regimens. Colonization levels overall were superior for strain 5, and the 9-day dosing schedule resulted in higher levels of both initial colonization and strain persistence. The indigenous streptococcal tongue populations of 20 (10.9%) of the 189 children in the 2-day trial showed markedly increased SalA-like inhibitory activity following use of the S. salivarius-supplemented milk. All 20 of these children were found to have had relatively small (<5% of total S. salivarius) indigenous tongue populations of SalA-producing S. salivarius, and the relative proportions and/or inhibitory activity of these SalA producers on the childrens' tongues increased following ingestion of the S. salivarius-supplemented milk. Because SalA is known to be strongly inhibitory to Streptococcus pyogenes, an important implication of this study is that the consumption of SalA-producing probiotic S. salivarius could potentially help to effect a sustained increase in SalA-mediated protection against S. pyogenes infection. PMID:17069620

  10. Bacteriocins and Its Applications in Food Preservation%细菌素及其在食品安全中的应用

    Institute of Scientific and Technical Information of China (English)

    周志江; 韩烨

    2005-01-01

    细菌素是细菌产生的抗细菌蛋白质,杀死或抑制其他细菌的生长.许多乳酸菌产生多种多样不同的细菌素,有作为天然、安全食品防腐剂的潜力.nisin是目前惟一用作食品防腐剂的细菌素,有50多个国家许可将其作为食品添加剂.近年来,对细菌素的研究有了很大的进展,本文就细菌素的分类、生物合成和作用方式、细菌素与抗生素的区别、安全性及在食品中的应用等方面进行综述.

  11. 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 ...

  12. Identification and Screening of Bacteriocin-producing Tetragenococcus halophilus%产细菌素嗜盐四联球菌的筛选及鉴定

    Institute of Scientific and Technical Information of China (English)

    王琳琳; 邹远军; 项松涛; 张云玲; 郑一敏; 胥秀英

    2013-01-01

    从传统露天酿造工艺的酱油中分离出12株乳球菌,对其进行形态、生理生化特性研究及16S rDNA序列分析,鉴定为嗜盐四联球菌.在排除酸作用后,WZ-3菌株发酵液对革兰氏阳性和革兰氏阴性细菌具有较好的抑菌活性,经胃蛋白酶、胰蛋白酶处理后,发酵液抑菌活性略有下降.因此初步认为该菌株为产细菌素的嗜盐四联球菌.

  13. Optimization of Fermentation Conditions for Bacteriocin Production by Lactobacillus helveticus AJT%瑞士乳杆菌AJT产细菌素的发酵条件优化

    Institute of Scientific and Technical Information of China (English)

    赵娜; 刘鑫; 周利娟; 白晓晔; 王荣平; 乌云达来

    2016-01-01

    瑞士乳杆菌AJT是一株广谱抗菌活性菌株,对革兰氏阳性、革兰氏阴性细菌和真菌均有较好的抑制作用。通过优化试验确定其最优的培养基成分为:乳糖15.0 g/L、酵母浸出粉7.0 g/L、胰蛋白胨6.0 g/L、牛肉浸膏12.0 g/L、乙酸钠7.0g/L、柠檬酸钠7.0 g/L、磷酸氢二钾2.0 g/L、硫酸镁200 mg/L、硫酸锰40 mg/L,吐温-801.0 g/L,起始pH6.5;最佳培养条件:接种量2.0%,37℃培养20 h。与未优化发酵条件相比,粗提取的瑞士乳杆菌AJT细菌素对蜡状芽孢杆菌的抗菌活性提高了53.8%,对黄色镰孢的抗菌活性提高了41.5%,对大肠杆菌的抗菌活性提高了68%。%Lactobacillus helveticus AJT is a broad antibacterial lactobacillus has strong antibacterial activity a-gainst Gram-positive, Gram-negative and fungi strains. Single factor and orthogonal tests were conducted to de termine the media for optimum antibacterial activity culture, and the optimized ingredient was:lactose 15.0 g/L, yeast extract 7.0 g/L, peptone 6.0 g/L, beef extract 12.0 g/L, sodium citrate hydrate 7.0 g/L, sodium acetate 7.0 g/L, K2HPO4 2.0 g/L, MgSO4·7H2O 200 mg/L, MnSO4·5H2O 40 mg/L and tween-80 1.0 g/L, with initial pH at 6.5, the optimum incubation parameters were incubated at 37℃for 20 h with 2%(volume fraction) con-centration. Its antibacterial activity of the extract increased 53.8%, 41.5%and 68%acting on Bacillus cereus , Fusarium culmorum and Escherichia coli respectively compared to the unoptimized fermentation condition.

  14. Draft Genome Sequence of the Bacteriocin-Producing Strain Enterococcus faecium M3K31, Isolated from Griffon Vultures (Gyps fulvus subsp. fulvus).

    Science.gov (United States)

    Arbulu, Sara; Frantzen, Cyril; Lohans, Christopher T; Cintas, Luis M; Herranz, Carmen; Holo, Helge; Diep, Dzung B; Vederas, John C; Hernández, Pablo E

    2016-01-01

    Enterococcus faeciumM3K31 is a bacteriocinogenic lactic acid bacterium (LAB) isolated from griffon vulture (Gyps fulvussubsp.fulvus) feces. The draft genome sequence of this strain provides genetic data that support its biotechnological potential. PMID:27013035

  15. 乳酸菌细菌素的生物合成与应用%Biological synthesis and application of bacteriocins

    Institute of Scientific and Technical Information of China (English)

    徐进; 冉陆; 罗雪云

    2002-01-01

    乳酸菌产生的细菌素是一类具有抑菌活性的多肽或蛋白质物质,大部分细菌素只对近缘关系的细菌有抑制作用,少数细菌素的抑菌谱较广,对多种革兰氏阳性细菌有很强的抑制作用.细菌素可分为热稳定的小分子肽、热敏感的大分子蛋白和羊毛硫抗生素三类.本文综述了细菌素的理化性质,生物合成与应用.

  16. Application of Bacteriocins in Aquaculture%细菌素研究进展及在水产养殖中的应用前景

    Institute of Scientific and Technical Information of China (English)

    张之文; 苏永全; 丁少雄; 王军

    2006-01-01

    细菌素是细菌产生的具有杀菌作用的一类多肽,分为广谱与窄谱.本文论述了细菌素的分类、遗传结构和作用机制,以及在食品工业、饲料和临床治疗中的应用,并阐述了细菌素在水产养殖病害防治中的潜在应用价值.

  17. Purification of Bacteriocin produced byLactobacillus pentosus 31-1%戊糖乳杆菌细菌素31-1的纯化

    Institute of Scientific and Technical Information of China (English)

    吕燕妮; 李平兰; 周伟

    2005-01-01

    为了研究戊糖乳杆菌31-1菌株产生的细菌素的性质,采用SP Sepharose Fast Flow阳离子交换树脂纯化细菌素,结果发现选用含0.1MNaCl的0.02M醋酸盐缓冲液即可洗脱下细菌素峰,比活力达到1259.84(AU/mg),是原发酵液的17倍,并且采用Tricine-SDS-PAGE法估测出细菌素的分子量大小在14.2kDa以下.

  18. Co-production of surfactin and a novel bacteriocin by Bacillus subtilis subsp. subtilis H4 isolated from bikalga, an African alkaline Hibiscus sabdariffa seed fermented condiment

    DEFF Research Database (Denmark)

    Compaore, C. S.; Nielsen, Dennis S.; Ouoba, L. I. I.;

    2013-01-01

    -ethanol resulted in a significant loss, indicative of the presence of disulfide bridges. The antimicrobial activity of H4 was heat resistant and active at pH3-10. PCR detection of yiwB, sboA, spoX, albA and spaS, etnS genes and genes coding for surfactins and plipastatins (fengycins) indicated a potential...

  19. Leucocins 4010 from Leuconostoc carnosum cause a matrix related decrease in intracellular pH of Listeria monocytogenes

    DEFF Research Database (Denmark)

    Fang, Weihuan; Budde, Birgitte Bjørn; Siegumfeldt, Henrik

    2006-01-01

    . monocytogenes was exposed to the bacteriocins leucocins 4010 and nisin either in a liquid filled chamber or on the surface of an agar containing bacteriocins. Both bacteriocins caused dissipation of the pH gradient in L. monocytogenes and the effect was clearly dependent on the matrix, as the decrease in p......Hi occurred much more rapidly in liquid than in agar....

  20. A two-component signal-transduction cascade in Carnobacterium piscicola LV17B : two signaling peptides and one sensor-transmitter

    NARCIS (Netherlands)

    Kleerebezem, M; Kuipers, OP; de Vos, WM; Stiles, ME; Quadri, LEN; Vos, Willem M. de; Stiles, Michael E.; Quadri, Luis E.N.

    2001-01-01

    In the lactic acid bacterium Carnobacterium piscicola LV17B a peptide-pheromone dependent quorum-sensing mode is involved in the regulation of bacteriocin production. Bacteriocin CB2 was identified as an environmental signal that induces bacteriocin production. Here, we demonstrate that a second 24

  1. Les bactériocines des bactéries lactiques : caractéristiques et intérêts pour la bioconservation des produits alimentaires

    Directory of Open Access Journals (Sweden)

    Dortu C.

    2009-01-01

    Full Text Available 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 food products to inhibit pathogenic or food-spoilage bacteria has then been suggested. This review focuses on the classification, structure, function, mode of action, biosynthesis and current food applications of bacteriocins from lactic acid bacteria.

  2. 产细菌素的戊糖片球菌的筛选及其细菌素的理化性质研究%Screening of Bacteriocin-producing Pediococcus pentosaceus Strain and Study on Physicochemical Characteristics of Bacteriocin

    Institute of Scientific and Technical Information of China (English)

    张红星; 刘丽; 谢远红; 熊丽霞; 刘慧

    2011-01-01

    从牛肉丸中分离筛选到1株具有抑菌活性的乳酸菌菌株N463,对单核细胞增生李斯特菌ATCC54003的生长具有良好的抑制作用.16S rDNA序列同源性分析鉴定乳酸菌N463为戊糖片球菌.在排除有机酸、过氧化氢的干扰后,确定该抑菌物质为蛋白类物质,即细菌素,命名为细菌素N463.理化性质研究表明细菌素N463具有较好的热稳定性、酸碱稳定性、可被人体内蛋白酶降解的特性.由此对戊糖片球菌所产细菌素N463有了初步的研究,为开发天然的肉制品防腐剂奠定理论基础.

  3. Assessing the antimicrobial activities of Ocins.

    Science.gov (United States)

    Choyam, Shilja; Lokesh, Dhanashree; Kempaiah, Bettadaiah Bheemakere; Kammara, Rajagopal

    2015-01-01

    The generation of a zone of inhibition on a solid substrate indicates the bioactivity of antimicrobial peptides such as bacteriocin and enterocin. The indicator strain plays a significant role in bacteriocin assays. Other characteristics of bacteriocins, such as their dispersal ability and the different zymogram components, also affect bacteriocin assays. However, universal well diffusion assays for antimicrobials, irrespective of their ability to diffuse (bacteriocin and enterocin), do not exist. The ability of different zymography components to generate non-specific activities have rarely been explored in the literature. The purpose of the present work was to evaluate the impact of major factors (diffusion and rate of diffusion) in a solid substrate bioassay, and to document the adverse effects of sodium dodecyl sulfate in zymograms used to estimate the approximate molecular weight of bacteriocins. PMID:26441952

  4. Assessing the antimicrobial activities of Ocins

    Directory of Open Access Journals (Sweden)

    Shilja eChoyam

    2015-09-01

    Full Text Available The generation of a zone of inhibition on a solid substrate indicates the bioactivity of antimicrobial peptides such as bacteriocin and enterocin. The indicator strain plays a significant role in bacteriocin assays. Other characteristics of bacteriocins, such as their dispersal ability and the different zymogram components, also affect bacteriocin assays. However, universal well diffusion assays for antimicrobials, irrespective of their ability to diffuse (bacteriocin, enterocin, do not exist. The ability of different zymography components to generate non-specific activities have rarely been explored in the literature. The purpose of the present work was to evaluate the impact of two major factors (diffusion and no diffusion in a solid substrate bioassay, and to document the adverse effects of sodium dodecyl sulfate in zymograms used to estimate the approximate molecular weight of bacteriocins.

  5. Lactic acid bacteria and their antimicrobial peptides : Induction,detection,partial characterization, and potential applications

    OpenAIRE

    Abbas Hilmi, Hanan

    2010-01-01

    Bacteriocin-producing lactic acid bacteria and their isolated peptide bacteriocins are of value to control pathogens and spoiling microorganisms in foods and feed. Nisin is the only bacteriocin that is commonly accepted as a food preservative and has a broad spectrum of activity against Gram-positive organisms including spore forming bacteria. In this study nisin induction was studied from two perspectives, induction from inside of the cell and selection of nisin inducible strains with increa...

  6. Common occurrence of antibacterial agents in human intestinal microbiota

    Directory of Open Access Journals (Sweden)

    Fatima eDrissi

    2015-05-01

    Full Text Available Laboratory experiments have revealed many active mechanisms by which bacteria can inhibit the growth of other organisms. Bacteriocins are a diverse group of natural ribosomally-synthesized antimicrobial peptides produced by a wide range of bacteria and which seem to play an important role in mediating competition within bacterial communities. In this study, we have identified and established the structural classification of putative bacteriocins encoded by 317 microbial genomes in the human intestine. On the basis of homologies to available bacteriocin sequences, mainly from lactic acid bacteria, we report the widespread occurrence of bacteriocins across the gut microbiota: 175 bacteriocins were found to be encoded in Firmicutes, 79 in Proteobacteria, 34 in Bacteroidetes and 25 in Actinobacteria. Bacteriocins from gut bacteria displayed wide differences among phyla with regard to class distribution, net positive charge, hydrophobicity and secondary structure, but the α-helix was the most abundant structure. The peptide structures and physiochemical properties of bacteriocins produced by the most abundant bacteria in the gut, the Firmicutes and the Bacteroidetes, seem to ensure low antibiotic activity and participate in permanent intestinal host defence against the proliferation of harmful bacteria. Meanwhile, the potentially harmful bacteria, including the Proteobacteria, displayed highly effective bacteriocins, probably supporting the virulent character of diseases. These findings highlight the eventual role played by bacteriocins in gut microbial competition and their potential place in antibiotic therapy.

  7. Bacteriocins produced by lactic acid bacteria and fermentation and application of nisin in food industry%乳酸菌的细菌素及乳链菌肽在食品工业中的发酵与应用

    Institute of Scientific and Technical Information of China (English)

    袁静; 李元端; 刘变芳; 田晓琴

    2002-01-01

    乳酸菌的细菌素是具有抗菌活性的多肽、蛋白质或蛋白质复合物,其中乳链菌肽是一种广泛应用的高效、无毒的天然食品防腐剂.评述了乳酸菌细菌素的分类剂乳链菌肽在食品工业中的发酵和应用前景.

  8. Classification, biosynthesis and their applications of bacteriocins produced from Lactic Acid Bacteria%乳酸菌细菌素的分类、生物合成及其应用

    Institute of Scientific and Technical Information of China (English)

    丹彤; 张和平

    2013-01-01

    细菌素是细菌在核糖体上合成的具有抗菌活性的多肽.许多乳酸菌都能生产细菌素,这些细菌素在同一生境中能杀灭或抑制引起食品腐败的细菌和病原菌的繁殖,可作为天然的食品防腐剂在食品中应用.综述主要描述了乳酸菌细菌素的分类、生物合成及其应用.

  9. Advances on purification, characterization and application of bacteriocin from lactic acid bacteria%乳酸菌素分离纯化和特性及在食品领域的应用研究进展

    Institute of Scientific and Technical Information of China (English)

    杜静芳; 缪璐欢; 白凤翎; 励建荣

    2016-01-01

    乳酸菌素是由某些乳酸菌核糖体合成的对相同或相近生境微生物具有拮抗作用的一类多肽、蛋白质类次级代谢产物,作为天然生物防腐剂已用于食品防腐保鲜领域.经过硫酸铵沉淀、凝胶层析和高效液相色谱等分离纯化流程获取乳酸菌素,进而对其热稳定性、pH适应性和分子量等进行分析,其中,乳酸菌素纯化技术是限制其研究和应用的技术瓶颈.本文对近几年乳酸菌素分离纯化如硫酸铵沉淀(ASP)、细胞吸附和解吸(ADPC)、甲醇丙酮萃取(MAE)、凝胶过滤层析(GFC)、阳离子交换色谱(CEC)、琼脂糖凝胶电泳(SP-SFF)和反向液相色谱(RP-HPLC)等技术及其综合运用进行比较分析,并对乳酸菌素性质研究和在食品领域的应用进展进行综述,为开发高效乳酸菌生物保护剂提供借鉴与参考.

  10. 细菌素产生菌的筛选及其细菌素的分离纯化%Screening, isolation and purification of the bacteriocin-producing bacteria

    Institute of Scientific and Technical Information of China (English)

    曾志刚; 陈英; 余柏松

    2003-01-01

    从香肠中分离得到一株产细菌素的乳酸片球菌,其发酵液经硫酸铵沉淀,CM-Sephadex C50阳离子交换柱层析后,得到的细菌素样品通过SDS-PAGE证明是一条带,分子量约20.83ku,该细菌素对热及酸碱稳定,易被酶降解而失去活性,对许多革兰氏阳性菌有较强的抑制作用,而对革兰氏阴性菌、酵母和霉没有作用.

  11. Effect on Bacteriocin Nisin to Extend Shelf Life of the Low-temperature of Cooked Meat%细菌素Nisin延长低温熟肉制品货架期的效果

    Institute of Scientific and Technical Information of China (English)

    陈果忠

    2009-01-01

    在低温肉制品加工过程中注入细菌素(Nisin),观察了其感官指标和细菌数的变化.结果表明,细菌素(Nisin)在低温肉制品中使用能有效抑制细菌繁殖速度,从而延长肉制品的货架期,较好地解决低温肉制品货架期短的问题.

  12. Identification of Lactobacillus plantarum ZJQ and characteristics of bacteriocin ZJQ%植物乳杆菌ZJQ的鉴定及其细菌素的生化特性

    Institute of Scientific and Technical Information of China (English)

    鲁渊; 宋达峰; 顾青

    2010-01-01

    从婴儿粪便中分离得到一株能产抑菌物质的乳酸菌菌株.形态学、生理生化和16S rDNA序列分析表明该菌为一株革兰氏阳性植物乳杆菌(Lactobacillus plantarum ZJQ).胰蛋白酶和蛋白酶K等酶学试验分析证明该菌所产抑菌物质为细菌素,初步纯化表明,该细菌素经100℃处理后仍有80%抑菌活性,具有良好的热稳定性;可抑制藤黄微球菌、金黄色葡萄球菌、大肠杆菌、沙门氏菌等,具有较广的抑菌谱.

  13. Screening of Bacteriocin-producing Lactic Acid Bacteria and Its Antibacterial Properties%产细菌素乳酸菌的筛选及其所产细菌素的特性

    Institute of Scientific and Technical Information of China (English)

    周配东; 潘道东; 张玉千; 丁海兵

    2011-01-01

    A lactic acid bacterial strain with broad-spectrum and obvious antibacterial activity,named as LPb1 was selected from soybean cheese by agar diffusion method.Based on 16S rDNA sequence alignment and physiological and biochemical analysis,the isolated strain was identified as Lactobacillus plantarum.The inhibitory activity of strain LPb1 fermentation supernatant was not affected by high temperature,1% TritonX-100,Tween-80,Tween-20,SDS,EDTA,or low pH(pH 〈5).However,its inhibitory activity revealed an obvious decrease after treatment with protease K and trypsin.Moreover,the fermentation supernatant of LPb1 strain could inhibit both some gram-positive bacteria and partial gram-negative bacteria.In contrast,the fermentation supernatant of LPb1 strain did not reveal inhibitory effect against yeast or mould.%利用牛津杯双层平板法从豆腐乳中筛选得到一株广谱的、具有较强抑菌活性的乳酸菌菌株,经生理生化分析及16S rDNA基因序列比对确定该菌株为植物乳杆菌(Lactobacillus plantarum)。该菌株发酵液经高温、聚乙二醇辛基苯基醚(TritonX-100)、吐温-80、吐温-20、十二烷基磺酸钠(SDS)、乙二胺四乙酸(EDTA)、尿素处理以及在低pH值(pH〈5)条件下均能够保持较好的抑菌活性,而其发酵产物的抑菌活性受胰蛋白酶和蛋白酶K的影响。抑菌谱实验表明,该菌株的发酵液对部分革兰氏阳性细菌和阴性细菌都有明显的抑制作用,但对酵母菌和霉菌无抑制作用。

  14. Study on the biological characteristics of bacteriocin produced by Lactobacillus acidophilus WS%嗜酸乳杆菌WS所产细菌素生物学特性的研究

    Institute of Scientific and Technical Information of China (English)

    张大为; 吕嘉枥

    2005-01-01

    Lactobacillus acidophilus WS在MRS培养基中经过37℃培养得到的细菌素经受70℃、121℃处理20min后,活性几乎不变,对以金黄色葡萄球菌为代表的革兰氏阳性菌有明显的抑制作用,而对大肠杆菌为代表的革兰氏阴性菌的抑制作用不明显,说明该细菌素是一种广谱抗菌的细菌素.细菌素对木瓜蛋白酶(papam)、蛋白酶K(proteinase K)以及胰蛋白酶(trypsin)敏感,而对中性蛋白酶(subtilsin)和胃蛋白酶(pepsin)的敏感性差.在一定的范围内,细菌素的抑菌活性和环境的酸度呈正相关.

  15. 鸡肠道中植物乳杆菌JX98所产细菌素的理化特性研究%A Study on Characteristics of Lactobacillus Bacteriocin JX98 from Chicken Cecal

    Institute of Scientific and Technical Information of China (English)

    黄微薇

    2012-01-01

    从鸡肠道内容物中分离筛选出1株产细菌素的菌株,通过生理生化法和16S rRNA测序分析进行鉴定。采用牛津杯法对抗菌肽的抗菌谱进行研究,利用N-羟甲基甲基甘氨酸-SDS-PAGE电泳确定细菌素的相对分子质量。%One bacterial strains were isolated from chicken cecal contents and identified basing on physiological and biochemeical characteristics determination,and 16s rRNA sequencing analysis.Oxford cup test was applied to assay the antimicrobial spectrum.

  16. NCBI nr-aa BLAST: CBRC-OLAT-26-0028 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-OLAT-26-0028 ref|ZP_00946292.1| RTX family calcium-binding cytotoxins and bact...eriocins [Ralstonia solanacearum UW551] gb|EAP71205.1| RTX family calcium-binding cytotoxins and bacteriocins [Ralstonia solanacearum UW551] ZP_00946292.1 2e-28 24% ...

  17. Genetic analysis of a novel plasmid encoded durancin locus in Enterococcus durans 41D

    Science.gov (United States)

    Enterococcus durans is commonly found in the intestinal tract in humans and animals and several strains are known to produce bacteriocins. Durancin GL, a novel bacteriocin of Enterococcus durans 41D with antilisterial activity was isolated from artisanal cheese samples and its genetic determinants ...

  18. Draft Genome Sequence of Probiotic Enterococcus faecium Strain L-3

    OpenAIRE

    Karaseva, Alena; Tsapieva, Anna; Pachebat, Justin; SUVOROV, Alexander

    2016-01-01

    We report here the draft genome sequence of the bacteriocin producer Enterococcus faecium strain L-3, isolated from a probiotic preparation, Laminolact, which is widely used in the Russian Federation. The draft genome sequence is composed of 74 contigs for a total of 2,643,001 bp, with 2,646 coding genes. Five clusters for bacteriocin production were found.

  19. Megaplasmids encode differing combinations of lantibiotics in Streptococcus salivarius.

    Science.gov (United States)

    Wescombe, Philip A; Burton, Jeremy P; Cadieux, Peter A; Klesse, Nikolai A; Hyink, Otto; Heng, Nicholas C K; Chilcott, Chris N; Reid, Gregor; Tagg, John R

    2006-10-01

    Streptococcus salivarius strains commonly produce bacteriocins as putative anti-competitor or signalling molecules. Here we report that bacteriocin production by the oral probiotic strain S. salivarius K12 is encoded by a large (ca. 190 kb) plasmid. Oral cavity transmission of the plasmid from strain K12 to a plasmid-negative variant of this bacterium was demonstrated in two subjects. Tests of additional S. salivarius strains showed large (up to ca. 220 kb) plasmids present in bacteriocin-producing isolates. Various combinations (up to 3 per plasmid) of loci encoding the known streptococcal lantibiotics salivaricin A, salivaricin B, streptin and SA-FF22 were localised to these plasmids. Since all bacteriocin-producing strains of S. salivarius tested to date appear to harbour plasmids, it appears that they may function as mobile repositories for bacteriocin loci, especially those of the lantibiotic class. PMID:16871420

  20. Characterization of lactococci isolated from homemade kefir

    Directory of Open Access Journals (Sweden)

    Kojić M.

    2007-01-01

    Full Text Available Five bacteriocin-producing lactococci isolates from traditionally prepared kefir were determined as Lactococcus lactis subsp. lactis. The analyzed isolates showed different plasmid profiles and no cross inhibition between them was detected. Moreover, natural isolate BGKF26 was resistant to the antimicrobial activity of nisin producing strain NP45. Plasmid curing experiments revealed that the genes encoding bacteriocin and proteinase production are located on separate genetic elements, except in BGKF26. Production of the tested bacteriocins depends on the concentration of casitone or triptone in the medium. Higher concentrations of casitone or triptone induce bacteriocin activity. Our DNA-DNA hybridization analyses suggest that the analyzed antimicrobial compounds probably are lactococcin-like bacteriocins.

  1. Food Applications and Regulation

    Science.gov (United States)

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

    This chapter deals with food applications of bacteriocins. Regulatory issues on the different possibilities for incorporating bacteriocins as bioprotectants are discussed. Specific applications of bacteriocins or bacteriocin-producing strains are described for main food categories, including milk and dairy products, raw meats, ready-to-eat meat and poultry products, fermented meats, fish and fish products or fermented fish. The last section of the chapter deals with applications in foods and beverages derived from plant materials, such as raw vegetable foods, fruits and fruit juices, cooked food products, fermented vegetable foods and ­fermented beverages. Results obtained for application of bacteriocins in combination with other hurdles are also discussed for each specific case, with a special emphasis on novel food packaging and food-processing technologies, such as irradiation, pulsed electric field treatments or high hydrostatic pressure treatment.

  2. Antibacterial Activity of Some Lactic Acid Bacteria Isolated from an Algerian Dairy Product

    Directory of Open Access Journals (Sweden)

    Abdelkader Mezaini

    2009-01-01

    Full Text Available In the present study, the antibacterial effect of 20 lactic acid bacteria isolates from a traditional cheese was investigated. 6 isolates showed antibacterial effect against Gram positive bacteria. Streptococcus thermophilus T2 strain showed the wide inhibitory spectrum against the Gram positive bacteria. Growth and bacteriocin production profiles showed that the maximal bacteriocin production, by S. thermophilus T2 cells, was measured by the end of the late-log phase (90 AU ml−1 with a bacteriocine production rate of 9.3 (AU ml−1 h−1. In addition, our findings showed that the bacteriocin, produced by S. thermophilus T2, was stable over a wide pH range (4–8; this indicates that such bacteriocin may be useful in acidic as well as nonacidic food. This preliminarily work shows the potential application of autochthonous lactic acid bacteria to improve safety of traditional fermented food.

  3. Assessment of the Bacteriocinogenic Potential of Marine Bacteria Reveals Lichenicidin Production by Seaweed-Derived Bacillus spp.

    Directory of Open Access Journals (Sweden)

    Gillian E. Gardiner

    2012-10-01

    Full Text Available The objectives of this study were (1 to assess the bacteriocinogenic potential of bacteria derived mainly from seaweed, but also sand and seawater, (2 to identify at least some of the bacteriocins produced, if any and (3 to determine if they are unique to the marine environment and/or novel. Fifteen Bacillus licheniformis or pumilus isolates with antimicrobial activity against at least one of the indicator bacteria used were recovered. Some, at least, of the antimicrobials produced were bacteriocins, as they were proteinaceous and the producers displayed immunity. Screening with PCR primers for known Bacillus bacteriocins revealed that three seaweed-derived Bacillus licheniformis harbored the bli04127 gene which encodes one of the peptides of the two-peptide lantibiotic lichenicidin. Production of both lichenicidin peptides was then confirmed by mass spectrometry. This is the first definitive proof of bacteriocin production by seaweed-derived bacteria. The authors acknowledge that the bacteriocin produced has previously been discovered and is not unique to the marine environment. However, the other marine isolates likely produce novel bacteriocins, as none harboured genes for known Bacillus bacteriocins.

  4. Qualitative detection of class IIa bacteriocinogenic lactic acid bacteria from traditional Chinese fermented food using a YGNGV-motif-based assay.

    Science.gov (United States)

    Liu, Wenli; Zhang, Lanwei; Yi, Huaxi; Shi, John; Xue, Chaohui; Li, Hongbo; Jiao, Yuehua; Shigwedha, Nditange; Du, Ming; Han, Xue

    2014-05-01

    In the present study, a YGNGV-motif-based assay was developed and applied. Given that there is an increasing demand for natural preservatives, we set out to obtain lactic acid bacteria (LAB) that produce bacteriocins against Gram-positive and Gram-negative bacteria. We here isolated 123 LAB strains from 5 types of traditional Chinese fermented food and screened them for the production of bacteriocins using the agar well diffusion assay (AWDA). Then, to acquire LAB producing class IIa bacteriocins, we used a YGNGV-motif-based assay that was based on 14 degenerate primers matching all class IIa bacteriocin-encoding genes currently deposited in NCBI. Eight of the LAB strains identified by AWDA could inhibit Gram-positive and Gram-negative bacteria; 5 of these were YGNGV-amplicon positive. Among these 5 isolates, amplicons from 2 strains (Y31 and Y33) matched class IIa bacteriocin genes. Strain Y31 demonstrated the highest inhibitory activity and the best match to a class IIa bacteriocin gene in NCBI, and was identified as Enterococcus faecium. The bacteriocin from Enterococcus avium Y33 was 100% identical to enterocin P. Both of these strains produced bacteriocins with strong antimicrobial activity against Listeria monocytogenes, Escherichia coli, and Bacillus subtilis, hence these bacteriocins hold promise as potential bio-preservatives in the food industry. These findings also indicated that the YGNGV-motif-based assay used in this study could identify novel class IIa bacteriocinogenic LAB, rapidly and specifically, saving time and labour by by-passing multiple separation and purification steps.

  5. Antimicrobial Activity Studies of Bactoriocin Produced by Lactobacilli Isolates from Carrot Kanji

    Directory of Open Access Journals (Sweden)

    Harshada M. Sowani

    2012-01-01

    Full Text Available Problem statement: In the present study, Staphylococcus aureus a causative agent of food poisoning is selected as a test organism to study the antimicrobial effect of bacteriocin. S. aureus produces number of exotoxins and enterotoxins which enters the body via contaminated food causing illness. Approach: In this case the use of antibiotics is one of the ways of treatment, but in addition to this if we advise such patients to consume the carrot kanji then it will cause better effect because carrot kanji is the naturally fermented food beverage consisting of microflora mainly the Lactobacilli. Results: The Lactobacilli have ability to produce antimicrobial compounds called bacteriocin. Isolation of bacteriocin was carried out from the naturally fermented carrot kanji. The bacteriocin produced by Lactobacilli was dialysed and used for the further studies. The well diffusion method is used to study the antimicrobial activity, effect of temperature, pH, enzymes on bacteriocin. From the diameter of zone of inhibition the activity of bacteriocin was determined. The sensitivity of bacteriocin at different pH range showed that at neutral pH the diameter of inhibition zone was greater than that at alkaline as well as acidic pH. Upto 100°C the bacteriocin activity was 80% but as temperature range increased upto 121°C it reduced sharply to 28%. Conclusion/Recommendations: In addition to this the effect of alpha amylase, trypsin, catalase enzyme on bacteriocin activity was also studied which shows positive results with alpha amylase, reduced activity with trypsin and catalase remained unaffected.

  6. Streptococcus salivarius mutants defective in mannose phosphotransferase systems show reduced sensitivity to mutacins I-T9 and R-3B.

    Science.gov (United States)

    Nicolas, Guillaume G; Frenette, Michel; Lavoie, Marc C

    2010-08-01

    Twenty-four mutacin-producing Streptococcus mutans strains were screened for their propensity to produce class II one-peptide bacteriocin using a deferred antagonism assay. Streptococcus salivarius and 3 mutants defective in their mannose phosphotransferase systems (mannose-PTS) were used as sensitive strains to identify which mannose-PTS could act as the docking site for class II one-peptide bacteriocin activity. We observed that only 2 strains of S. mutans, T9 and 3B, potentially produce class II one-peptide bacteriocin, namely mutacins I-T9 and R-3B, but with no preference for any mannose-PTS complex as a target. PMID:20725132

  7. PURIFICATION AND CHARACTERIZATION OF NISIN PRODUCED BY LACTOCOCCUS LACTIS ISOLATED FROM INDIAN CURD

    Directory of Open Access Journals (Sweden)

    Saba A. Mahdy

    2015-12-01

    Full Text Available Lactococcus lactis isolated from traditional dairy Indian curd. Strains were preliminarily identified by PCR analysis and partial 16S rRNA confirmed that N5 were 100% identical to Lactococcus. lactis sp. lactis. The results revealed that only the bacteriocin produced from strain N5 was shown as being active against mostly gram positive bacteria The bacteriocin produced purified by precipitation followed by loading with gel chromatography. The partially purified bacteriocin was found to be stable over a wide range of pH, temperature and enzymes. The molecular weight of the peptide was judged to be 3.5 kDa by SDSpolyacrylamide gel electrophoresis.and conform to the result of mass spectrometry by maldi-tof test which calculated the mass of 3354.07 Da for nisin.These results indicate that bacteriocin produced by L. lactis sp. lactis N5 is a nisin.

  8. Screening and development trend of antimicrobial peptides from Lactic acid bacteria%乳酸菌抗菌肽的筛选及发展趋势

    Institute of Scientific and Technical Information of China (English)

    崔艳华; 陈章庭; 张超; 丁忠庆; 王云峰; 张兰威

    2012-01-01

    筛选新型、广谱、天然的抗茵肽,是当前食品安全领域研究的热点问题.建立高效筛选方法,将加速新型抗茵肽的发现和应用.本文就当前乳酸菌抗菌肽筛选方法及发展趋势进行阐述.%At present, screening novel broad-spectrum and native bacteriocins is a focus in field of food safe. Developing rapid and high-throughput approaches for identification of bacteriocins potential will accelerate discovery and applications of novel bacteriocins. The detection and screening strategies of bacteriocins from lactic acid bacteria were reviewed in this paper.

  9. Gclust Server: 167488 [Gclust Server

    Lifescience Database Archive (English)

    Full Text Available 167488 Bsu_BSU37380=albB Cluster Sequences - 53 antilisterial bacteriocin (subtilos...bB Link to cluster sequences Cluster Sequences Link to related sequences - Sequence length 53 Representative annotation antilisteria

  10. Gclust Server: 167491 [Gclust Server

    Lifescience Database Archive (English)

    Full Text Available 167491 Bsu_BSU37410=albE Cluster Sequences - 386 antilisterial bacteriocin (subtilo...lbE Link to cluster sequences Cluster Sequences Link to related sequences - Sequence length 386 Representative annotation antilisteri

  11. Gclust Server: 167302 [Gclust Server

    Lifescience Database Archive (English)

    Full Text Available 167302 Bsu_BSU37430=albG Cluster Sequences - 233 antilisterial bacteriocin (subtilo...lbG Link to cluster sequences Cluster Sequences Link to related sequences - Sequence length 233 Representative annotation antilisteri

  12. Gclust Server: 166708 [Gclust Server

    Lifescience Database Archive (English)

    Full Text Available 166708 Bsu_BSU37400=albD Cluster Sequences - 436 antilisterial bacteriocin (subtilo...lbD Link to cluster sequences Cluster Sequences Link to related sequences - Sequence length 436 Representative annotation antilisteri

  13. Nisin H Is a New Nisin Variant Produced by the Gut-Derived Strain Streptococcus hyointestinalis DPC6484

    OpenAIRE

    O'Connor, Paula M.; O'Shea, Eileen F.; Guinane, Caitriona M.; O'Sullivan, Orla; Cotter, Paul D.; Ross, R. Paul; Hill, Colin

    2015-01-01

    Accumulating evidence suggests that bacteriocin production represents a probiotic trait for intestinal strains to promote dominance, fight infection, and even signal the immune system. In this respect, in a previous study, we isolated from the porcine intestine a strain of Streptococcus hyointestinalis DPC6484 that displays antimicrobial activity against a wide range of Gram-positive bacteria and produces a bacteriocin with a mass of 3,453 Da. Interestingly, the strain was also found to be im...

  14. Antilisterial activity of bacteriocinogenic Pediococcus acidilactici HA6111-2 and Lactobacillus plantarum ESB 202 grown under pH and osmotic stress conditions

    OpenAIRE

    Engelhardt, Tekla; Albano, Helena; Kisk, Gabriella; Acsi-Farkas, Csilla Moh; Teixeira, Paula

    2015-01-01

    Bacteriocin producing lactic acid bacteria (LAB) cultures can be used as biopreservatives in fermented food products; thus the food industry is interested in stable cultures that produce bacteriocins consistently. Inhibtion of Listeria spp. by bacteriocinogenic Pediococcus acidilactici and Lactobacillus plantarum (both isolated from fermented meats) was investigated under conditions of stress induced by low pH and high salt concentrations. Listeria monocytogenes serogroup IIb (fro...

  15. Anti-MRSA Activities of Enterocins DD28 and DD93 and Evidences on Their Role in the Inhibition of Biofilm Formation

    OpenAIRE

    Al Atya, Ahmed K.; Belguesmia, Yanath; Chataigne, Gabrielle; Ravallec, Rozenn; Vachée, Anne; Szunerits, Sabine; Boukherroub, Rabah; Drider, Djamel

    2016-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) has become a worrisome superbug. This work aimed at studying the effects of two class IIb bacteriocins, enterocins DD28 and DD93 as anti-MRSA agents. Thus, these bacteriocins were purified, from the cultures supernatants of Enterococcus faecalis 28 and 93, using a simplified purification procedure consisting in a cation exchange chromatography and a reversed-phase high-performance liquid chromatography. The anti-Staphylococcal activity was sh...

  16. Anti-MRSA activities of Enterocins DD28 and DD93 and evidences on their role in the inhibition of biofilm formation

    OpenAIRE

    Ahmed Khassaf eAL ATYA; Yanath ebelguesmia; Gabrielle eChataigné; Rozenn eRavallec; Anne eVachée; Sabine eSzunerits; Rabah eBoukherroub; Djamel eDrider

    2016-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA), along with other antibiotic resistant bacteria, has become a worrisome superbug worldwide. This work was aimed at studying the efficacies of two class IIb bacteriocins, enterocins DD28 and DD93, against MRSA-S1 grown in planktonic culture and embedded in biofilms. These bacteriocins were purified, from the cultures supernatants of Enterococcus faecalis 28 and 93, using a simplified purification procedure consisting in a cation exchange chrom...

  17. Nisin and its Antimicrobial Effect in Foods

    OpenAIRE

    Hamparsun Hampikyan; Hilal Colak

    2007-01-01

    Nisin is a bacteriocin which is produced by Lactococcus lactis and takes its place in I. class bacteriocins which are known as lantibiotics. Nisin has antimicrobial and bactericidal activity against a broad spectrum of gram positive bacteria and spores of Clostridium spp. and Bacillus spp. According to toxicity studies nisin is considered not toxic to humans. Its first established used was as a preservative in processed cheese products and since than numerous other applications in various foo...

  18. Evaluation of microbial adjuncts and their effect on the ripening of cheddar cheese

    OpenAIRE

    Ristagno, Diletta

    2013-01-01

    A bacteriocin-producing strain of Lactobacillus paracasei DPC 4715 was used as an adjunct culture in Cheddar cheese in order to control the growth of “wild” nonstarter lactic acid bacteria. No suppression of growth of the indicator strain was observed in the experimental cheese. The bacteriocin produced by Lactobacillus paracasei DPC 4715 was sensitive to chymosin and cathepsin D and it may have been cleaved by the rennet used for the cheese manufactured or by indigenous milk proteases. A ser...

  19. Efecto de las condiciones de crecimiento y composición del medio de cultivo sobre la producción de bacteriocina de Enterococcus mundtii Tw56

    Directory of Open Access Journals (Sweden)

    Marisol Vallejo

    2014-12-01

    Full Text Available Enterococcus mundtii Tw56 is a bacteriocin-producing strain that was isolated from intestinal content of silverside (Odontesthes sp.. The aim of the present work was to determine physicochemical factors and culture medium composition for higher yield of viable cells and bacteriocin production. No changes were observed in the antimicrobial production when glucose was replaced by fructose or maltose in the MRS medium formulation. On the other hand, highest bacteriocin activity was obtained when meat extract was used as a sole nitrogen source. While the maximun biomass was achieved at35 ºC, the optimal temperatures for bacteriocin production were observed at 25 and30 ºC. The optimal initial pH for cell growth and bioactivity was 6.5, both parameters dropped when the experience started at pH 6.0 or 5.5. Biomass formation and bacteriocin production decreased in the presence of sodium chloride. The strain started producing the bacteriocin at the late exponential phase. The activity increased as a function of the cell mass and reached the maximun at the end of exponential phase (12 h. A decrease of antimicrobial activity was observed in the stationary phase (16 h, possibly due to degradation by proteolitic enzimes.

  20. Competitive advantage of bacteriocinogenic strains within lactic acid bacteria consortium of raw milk cheese

    Directory of Open Access Journals (Sweden)

    Irena Rogelj

    2011-03-01

    Full Text Available The presence of gene determinants for different bacteriocins has been already demonstrated in traditional Slovenian types of raw milk cheeses ‘Tolminc’ and ‘Kraški’. These genes were present also in the cultivable microbiota. In this research the aim was to establish how the presence of gene determinants for bacteriocins in microbial consortia is reflected in its antimicrobial activity. In addition, one of the goals was to determine whether the strains that carry gene determinants for bacteriocins have any competitive growth advantage in microbial population. Microbial consortium of ‘Tolminc’ cheese was propagated in milk and examined at the end of propagation its antimicrobial activity and the presence of gene determinants for bacteriocins. Comparison of the results obtained before and after propagation leaded to the conclusion that most of the strains possessing gene determinants for bacteriocins were unable to persist during propagation. The strains which did persist during propagation carried gene determinants for enterocins P, L50B and cytolysin. Antimicrobial activity of consortium before and after propagation was not substantially different and cannot be attributed to any of detected bacteriocins.

  1. CHARACTERIZATION OF THE PARTIALLY PURIFIED PLANTARCIN SR18 PRODUCED BY LACTOBACILLUS PLANTARUM SR18

    Directory of Open Access Journals (Sweden)

    Wagih El-Shouny

    2013-04-01

    Full Text Available The bacteriocin bound to the cells and that secreted into the culture filtrate of Lactobacillus plantarum SR18 were precipitated by 75% ammomium sulphate, dialysed and further purified by Gel filtration on Sephadex G-100. Bacteriocins were purified from proteins bound to the cell of L. plantarum SR18 (plantarcin SR18 a and culture filtrate proteins (plantarcin SR18 b, respectively. The SDS-PAGE of partially purified Plantarcin SR18a showed a molecular weight of 3.5 KDa. While, plantarcin SR18 b had a molecular weight of 10.3 KDa. The antibacterial activity of the tested plantarcin SR18 preparations suffered no measurable loss after 45 min at 80ºC. Whereas, At 100ºC, significant decrease in the activity of bacteriocin preparations (60- 80 % took place by the end of 45 min. At pH ranged from 5-8, the activity of the plantarcin SR18 preparations suffered no measurable loss. Dissociating agents significantly affected the bacteriocin activity. Thus, tween 80 and mercaptoethanol increased the activity of bacteriocin preparations to 1.2-1.4 fold. Sodium dodecyl sulphate (SDS increased the activity of the tested bacteriocin preparations by about 20%.The lowest residual activity (60% was recorded after treatment with Triton X100 for 45 min. Protease completely inhibited the activities of all forms of plantarcin SR18 after 45 min at 37ºC.

  2. Control of Listeria monocytogenes in fresh cheese using protective lactic acid bacteria.

    Science.gov (United States)

    Coelho, M C; Silva, C C G; Ribeiro, S C; Dapkevicius, M L N E; Rosa, H J D

    2014-11-17

    In the past years, there has been a particular focus on the application of bacteriocins produced by lactic acid bacteria (LAB) in controlling the growth of pathogenic bacteria in foods. The aim of this study was to select LAB strains with antimicrobial activity, previously isolated from a traditional Azorean artisanal cheese (Pico cheese), in order to identify those with the greatest potential in reducing Listeria monocytogenes in fresh cheese. Eight bacteriocin producer strains identified as Lactococcus lactis (1) and Enterococcus faecalis (7) were tested. In general, the bacteriocin-producing strains presented a moderate growth in fresh cheese at refrigeration temperatures (4 °C), increasing one log count in three days. They exhibited slow acidification capacity, despite the increased production of lactic acid displayed by some strains after 24h. Bacteriocin activity was only detected in the whey of fresh cheese inoculated with two Enterococcus strains, but all cheeses made with bacteriocin-producing strains inhibited L. monocytogenes growth in the agar diffusion bioassay. No significant differences were found in overall sensory evaluation made by a non-trained panel of 50-52 tasters using the isolates as adjunct culture in fresh cheese, with the exception of one Enterococcus strain. To test the effect of in situ bacteriocin production against L. monocytogenes, fresh cheese was made from pasteurized cows' milk inoculated with bacteriocin-producing LAB and artificially contaminated with approximately 10(6) CFU/mL of L. monocytogenes. The numbers of L. monocytogenes were monitored during storage of fresh cheese at refrigeration temperature (4 °C) for up to 15 days. All strains controlled the growth of L. monocytogenes, although some Enterococcus were more effective in reducing the pathogen counts. After 7 days, this reduction was of approximately 4 log units compared to the positive control. In comparison, an increase of 4 log CFU/mL in pathogen numbers was

  3. Effect of a bacteriocin-producing strain of Bifidobacterium L-SN on the postacidification and quality of yohurt%产细菌素双歧杆菌L-SN对酸奶后酸化及品质的影响

    Institute of Scientific and Technical Information of China (English)

    尚楠; 刘丽莎; 任发政; 李平兰

    2013-01-01

    The study was carried out to restrain postacidifacation of set yoghurt using Bifidobacterium L-SN with mixed leaven together for fermentation.By measuring the changes of pH value,titratable acidity,the number of viable cells,water hold capacity,viscosity and sensory evaluation in 20 days under the storage condition of 4 ℃,we find adding LSN can efficiently restrain posfacidification of set yoghurt and improve the quality.The results indicate that the best supplemental level is (2-5) × 106 cfu/mL.In 20 days,the pH value is 4.1-4.2;the titratable acidity is 100-110 °T and the number of viable cells are more than 106 cfu/mL.In addition,it can significantly improve the water holding capacity and viscosity and to give good color,texture and organization state of the set yoghurt.%选择产细菌素双歧杆菌L-SN菌株与保加利亚乳杆菌和嗜热链球菌混合发酵剂配伍共同发酵生产酸奶,通过测定4℃贮藏条件下酸奶的pH、可滴定酸度、活菌数、持水力和黏度等指标的变化探讨产细菌素双歧杆菌对酸奶后酸化效果及品质的影响.结果显示:双歧杆菌L-SN的加入能有效抑制酸奶的后酸化,以添加水平为(2~5)×106 cfu/mL为最佳,可在20 d贮藏期内维持酸度为100~110°T、pH 4.1~4.2、活菌数≥106 cfu/mL,并能显著提高酸奶的持水力和黏度,赋予酸奶良好的色泽、口感和组织状态.

  4. 耐低温肠球菌Enterococcus sp.MB2-1产细菌素的生物学特性%Biological Characterization of Bacteriocin Produced by Cold-Adapted Enterococcus sp.MB2-1

    Institute of Scientific and Technical Information of China (English)

    邓梅; 王俊钢; 高阳; 倪永清

    2013-01-01

    从新疆阿勒泰地区额尔齐斯河流域冷水鱼肠道筛选到一株产细菌素的菌株MB2-1,牛津杯法实验显示该菌株抑制革兰氏阳性菌李斯特氏菌(Listeria monocytogenes)、金黄色葡萄球菌(Staphylococcus aureus)、枯草芽孢杆菌(Bacillus subtilis)以及革兰氏阴性菌大肠杆菌(Escherichia coli)的生长.通过形态学和16S rRNA基因序列同源性分析初步鉴定该菌株隶属于Enterococcus属.菌株Enterococcus sp.MB2-1的最适生长温度在24℃左右,属于耐冷菌.细菌素MB2-1对胃蛋白酶、胰蛋白酶及尿素敏感,过氧化氢酶、Triton X-100、SDS、吐温-80、NaCl和EDTA处理抑菌活性保持稳定,该细菌素具有良好的pH值稳定性(3.0~9.0)和热稳定性(100℃、60min),但在121℃、20min处理后抑菌活性消失.在菌株生长9h后发现抑菌活性,并且在生长稳定期检测到最高抑菌活性.

  5. Daya Antibakteri Filtrat Asam Laktat dan Bakteriosin Lactobacillus bulgaricus KS1 dalam Menghambat Pertumbuhan Klebsiella pneumoniae Strain ATCC 700603, CT1538, dan S941

    Directory of Open Access Journals (Sweden)

    Prima Nanda Fauziah

    2015-03-01

    Full Text Available Lactobacillus bulgaricus produces lactic acid and bacteriocin which have been reported to have various pharmacologic properties, including their role an antibacterial agent. Klebsiella pneumoniae, as an agent of pneumonia, remains a public health problem in tropical countries. This study was aimed to observe the antibacterial activities of lactic acid filtrate and bacteriocins of L. bulgaricus toward againsts K. pneumoniae strains by in vitro experiment. The experiment took place in Microbiology Laboratory, Teaching Hospital, Padjadjaran University, Bandung, August–October 2012. In vitro laboratory analytic study has been conducted on lactic acid filtrate and bacteriocins of L. bulgaricus against the K. pneumoniae strains. The study used agar pour plate and agar disk diffusion method and analyzed by ANAVA followed by Duncan’s multiple range test (DMRT. The 30% lactic acid filtrate and 20% bacteriocins filtrate concentrations of L. bulgaricus showed bactericidal characteristics againts the growth of K. pneumoniae strains. Greater concentration of lactic acid filtrate and bacteriocins of L. bulgaricus led toincreasing effect of growth inhibition zones of K. pneumoniae strains. Statistical analysis of variance (ANOVA showed that the greatest concentration effect of L. bulgaricus filtratefor inhibiting K. pneumoniae strains was achieved in 90% lactic acid filtrate concentration treatment, whereas the greatest inhibition zones for K. pneumoniae ATCC 700603 was obtaubed in 90% bacteriocins filtrate concentration, amounting 16.667 mm. In conclusion, lactic acid filtrate and bacteriocins L. bulgaricus have antibacterial effects on K. pneumoniae. The level of antibacterial effect of L. bulgaricus against the growth of K. pneumoniae strains depends on the type of filtrate, L. bulgaricus filtrate concentration, and K. pneumoniae strain.

  6. Anti-MRSA activities of Enterocins DD28 and DD93 and evidences on their role in the inhibition of biofilm formation

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    Ahmed Khassaf eAL ATYA

    2016-05-01

    Full Text Available Methicillin-resistant Staphylococcus aureus (MRSA, along with other antibiotic resistant bacteria, has become a worrisome superbug worldwide. This work was aimed at studying the efficacies of two class IIb bacteriocins, enterocins DD28 and DD93, against MRSA-S1 grown in planktonic culture and embedded in biofilms. These bacteriocins were purified, from the cultures supernatants of Enterococcus faecalis 28 and 93, using a simplified purification procedure consisting in a cation exchange chromatography and a reversed-phase high-performance liquid chromatography. The anti-Staphylococcal activity of these bacteriocins was shown in-vitro by the assessment of the minimal inhibitory concentration (MIC. Afterwhich, a checkerboard and time-kill kinetics permitted unveiled a synergistic effect of these bacteriocins in combination with erythromycin and kanamycin against the clinical MRSA-S1. These bacteriocins alone or in combination with erythromycin and kanamycin were able to impede the formation of MRSA-S1 biofilms on stainless steel and glace devices as supported by the microbial cell counts, epifluorescence and Scanning Electron Microscope analyses.

  7. Characterization of bacteriocinogenic strains of lactic acid bacteria from traditional Slovenian cheese ‘Tolminc’

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    Aljoša Trmčić

    2010-12-01

    Full Text Available The purpose of this research was to examine traditional Slovenian ‘Tolminc’ cheese for the presence of lactic acid bacteria that produce several bacteriocins. The presence of gene determinants for different bacteriocins in this type of cheese and in the cultivable population of ‘Tolminc’ microbiota, have already been demonstrated, as well as its antimicrobial activity. Due to the difficulties in connecting the presence of gene determinants for bacteriocins with the observed antimicrobial activity it was decided to examine in this study the same features on the level of individual bacteriocinogenic strains. Like in previous results, enterococci and their bacteriocins prevailed in cheese microbial consortia. None of isolated strains inhibited growth of Staphylococcus aureus, while the other indicator strains were inhibited in a strain specific manner. Most of isolated strains carried gene determinants for cytolysin. On the basis of gene determinants for bacteriocins, antimicrobial activity, phenotyping by PhP (PhenePlateTM system and PCR identification, some similarities found were among Enterococcus isolates.

  8. High Frequency and Diversity of Antimicrobial Activities Produced by Nasal Staphylococcus Strains against Bacterial Competitors.

    Science.gov (United States)

    Janek, Daniela; Zipperer, Alexander; Kulik, Andreas; Krismer, Bernhard; Peschel, Andreas

    2016-08-01

    The human nasal microbiota is highly variable and dynamic often enclosing major pathogens such as Staphylococcus aureus. The potential roles of bacteriocins or other mechanisms allowing certain bacterial clones to prevail in this nutrient-poor habitat have hardly been studied. Of 89 nasal Staphylococcus isolates, unexpectedly, the vast majority (84%) was found to produce antimicrobial substances in particular under habitat-specific stress conditions, such as iron limitation or exposure to hydrogen peroxide. Activity spectra were generally narrow but highly variable with activities against certain nasal members of the Actinobacteria, Proteobacteria, Firmicutes, or several groups of bacteria. Staphylococcus species and many other Firmicutes were insusceptible to most of the compounds. A representative bacteriocin was identified as a nukacin-related peptide whose inactivation reduced the capacity of the producer Staphylococcus epidermidis IVK45 to limit growth of other nasal bacteria. Of note, the bacteriocin genes were found on mobile genetic elements exhibiting signs of extensive horizontal gene transfer and rearrangements. Thus, continuously evolving bacteriocins appear to govern bacterial competition in the human nose and specific bacteriocins may become important agents for eradication of notorious opportunistic pathogens from human microbiota.

  9. Co-expression and characterization of enterocin CRL35 and its mutant in Escherichia coli Rosetta

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    Masías Emilse

    2014-01-01

    Full Text Available Even though many sequences and structures of bacteriocins from lactic acid bacteria have been fully characterized so far, little information is currently available about bacteriocins heterologously produced by Escherichia coli. For this purpose, the structural gene of enterocin CRL35, munA, was PCR-amplified using specific primers and cloned downstream of PelB sequence in the pET22b (+ expression vector. E. coli Rosetta (DE3 pLysS was chosen as the host for production and enterocin was purified by an easy two-step protocol. The bacteriocin was correctly expressed with the expected intramolecular disulfide bond. Nevertheless, it was found that a variant of the enterocin, differing by 12 Da from the native polypeptide, was co-expressed by E. coli Rosetta in comparable amount. Indeed, the mutant bacteriocin contained two amino acid substitutions that were characterized by matrix assisted laser desorption ionization-time of flight (MALDI-TOF and HPLCelectrospray (ESI-Q-TOF tandem mass spectrometry (MS/ MS sequencing. This is the first report regarding the production of mutants of pediocin-like bacteriocins in the E. coli expression system.

  10. ANTIMICROBIAL ACTIVITY OF LACTIC ACID BACTERIAL ISOLATES

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    Utkarsha S. Shivsharan

    2013-08-01

    Full Text Available Micro-organisms have tendency to produce antimicrobial substances which show biological activity against other kind of micro-organisms. This phenomenon of bacterial antagonism is observed in lactic acid bacteria with competitive advantages. The lactic acid bacteria are commonly present in many fermented products, fruits and milk products. The variety of antimicrobial substances produced by lactic acid bacteria showing good inhibition capacity include production of lactic acid, acetic acid, hydrogen peroxide, carbon dioxide, diacetyl and bacteriocin. Bacteriocins produced by lactic acid bacteria are the subject of intense research because of their antimicrobial activity against food born bacteria such as Listeria monocytogenes, staphylococcus aureus, Bacillus cereus, Clostridium botulinum and several others .Bacteriocins may be bacteriostatic or bactericidal with narrow or broad range of activity. The main of the study was to study the antimicrobial activity of such lactic acid bacterial isolates.

  11. Characterization of antimicrobial substance from Lactobacillus salivarius KL-D4 and its application as biopreservative for creamy filling.

    Science.gov (United States)

    Therdtatha, Phatthanaphong; Tandumrongpong, Chanabhorn; Pilasombut, Komkhae; Matsusaki, Hiromi; Keawsompong, Suttipun; Nitisinprasert, Sunee

    2016-01-01

    Lactobacillus salivarius KL-D4 isolated from duck intestine produced bacteriocin which was stable at high temperature and a wide pH range of 3-10. Its cell free supernatant at pH 5.5 exhibited wide inhibitory spectrum against both G+ and G- bacteria. The highest bacteriocin production was obtained in MRS broth supplemented with 0.5 % (w/v) CaCO3 at 6 h by gentle shaking. PCR walking using specific primers at the conserved region of class-II bacteriocin resulted in 4 known genes of kld1, kld2, kld3 and kld4 with 100 % similarity to genes encoding for salivaricin α, β, induction peptide and histidine protein kinase of Lb. salivarius GJ-24 which did not previously report for bacteriocin characterization, while showing 94, 93, 59 and 62 % to other salivaricin gene cluster, respectively. The high activities of 25,600 AU/ml indicated a strong induction peptide expressed by kld3 which has low similarity to previous inducer reported. Based on operon analysis, only kld1, kld3 and kld4 could be expressed and subsequently elucidated that only salivaricin α like bacteriocin was produced and secreted out of the cells. Using protein purification, only a single peptide band obtained showed that this strain produced one bacteriocin which could be salivaricin α namely salivaricin KLD showing about 4.3 kDa on SDS-PAGE. Partial purification by 20 % ammonium sulfate precipitation of the product was tested on the artificial contamination of creamy filling by Bacillus cereus, Enterococcus faecalis, Pseudomonas stutzeri, Staphylococcus sp. and Stenotrophomonas sp. resulting the growth inhibitory efficiency of 4.45-66.9, 11.5-100, 100, 0-28.1 and 5-100 % respectively. Therefore, salivaricin KLD can be a tentative biopreservative for food industry in the future. PMID:27462508

  12. In vitro fermentation studies for selection and evaluation of Bacillus strains as starter cultures for the production of okpehe, a traditional African fermented condiment.

    Science.gov (United States)

    Oguntoyinbo, Folarin A; Sanni, Abiodun I; Franz, Charles M A P; Holzapfel, Wilhelm H

    2007-01-25

    Selected Bacillus and Enterococcus strains, isolated from traditional okpehe fermentations, were studied for their suitability as starter cultures in laboratory-scale fermentations of Prosopis africana seeds for the production of okpehe, a traditional fermented vegetable product of Nigeria. The strains were selected on the basis of highest proteolytic activity, as determined with the APIZYM (BioMerieux) test. The choice of starter strains was narrowed to Bacillus subtilis strains BFE 5301 and BFE 5372. These were determined as the best starter combination because of rapid growth, high amylolytic and proteolytic activities, high levels of polyglutamic acid production by strain BFE 5372, as well as bacteriocin production by strain BFE 5301. Other mixed culture fermentations did not yield sensorically acceptable products. Although a monoculture fermentation, using only B. subtilis strain BFE 5372, produced okpehe with very good sensory characteristics, the growth of B. cereus could be detected after 48 h fermentation, indicating that this starter did not sufficiently contribute to product safety. Mixed culture fermentation with the combination of bacteriocin-producing starter B. subtilis BFE 5301 and the non-bacteriocin-producing B. subtilis BFE 5372, produced a product with good sensory characteristics, in which growth of B. cereus was delayed. The bacteriocin produced by B. subtilis strain BFE 5301 was identified as subtilisin, using subtilisin-specific primers and PCR amplification of the subtilisin gene. The bacteriocin was heat-stable at 100 degrees C for 10 min and exhibited highest activity at pH values lower or equal to pH 6.0. The bacteriocin was sensitive to the proteolytic enzymes trypsin and alpha-chymotrypsin at concentrations of 10 mg/ml.

  13. Antimicrobial properties of lactic acid bacteria isolated from uruguayan artisan cheese

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    Martín Fraga Cotelo

    2013-12-01

    Full Text Available Uruguayan artisan cheese is elaborated with raw milk and non-commercial starters. The associated native microbiota may include lactic acid bacteria and also potentially pathogenic bacteria. Lactic acid bacteria were isolated from artisan cheese, raw milk, and non-commercial starter cultures, and their potential bacteriocin production was assessed. A culture collection of 509 isolates was obtained, and five isolates were bacteriocin-producers and were identified as Enterococcus durans,Lactobacillus casei, and Lactococcus lactis. No evidence of potential virulence factors were found in E. durans strains. These are promising results in terms of using these native strains for cheese manufacture and to obtain safe products.

  14. Growth inhibition of Listeria monocytogenes by a nonbacteriocinogenic Carnobacterium piscicola

    DEFF Research Database (Denmark)

    Nilsson, Lilian; Bech Hansen, T.; Garrido, P.;

    2005-01-01

    Aims: This study elucidates the mechanisms by which a nonbacteriocinogenic Carnobacterium piscicola inhibits growth of Listeria monocytogenes. Methods and Results: Listeria monocytogenes was exposed to live cultures of a bacteriocin-negative variant of C. piscicola A9b in co-culture, in a diffusion...

  15. The structure of the lantibiotic lacticin 481 produced by Lactococcus lactis : location of the thioether bridges

    NARCIS (Netherlands)

    Hooven, Henno W. van den; Lagerwerf, Fija M.; Heerma, Wigger; Haverkamp, Johan; Piard, Jean-Christophe; Hilbers, Cornelis W.; Siezen, Roland J.; Kuipers, Oscar P.; Rollema, Harry S.

    1996-01-01

    The lantibiotic lacticin 481 is a bacteriocin produced by Lactococcus lactis ssp. lactis. This polypeptide contains 27 amino acids, including the unusual residues dehydrobutyrine and the thioether-bridging lanthionine and 3-methyllanthionine. Lacticin 481 belongs to a structurally distinct group of

  16. Analysis of the promoters involved in enterocin AS-48 expression

    NARCIS (Netherlands)

    Cebrián, Rubén; Rodríguez-Ruano, Sonia; Martínez-Bueno, Manuel; Valdivia, Eva; Maqueda, Mercedes; Montalbán-López, Manuel

    2014-01-01

    The enterocin AS-48 is the best characterized antibacterial circular protein in prokaryotes. It is a hydrophobic and cationic bacteriocin, which is ribosomally synthesized by enterococcal cells and post-translationally cyclized by a head-to-tail peptide bond. The production of and immunity towards A

  17. Gene expression profiling of a nisin-sensitive Listeria monocytogenes Scott A CtsR deletion mutant

    Science.gov (United States)

    Listeria monocytogenes is a food-borne pathogen of significant threat to public health. Nisin is the only bacteriocin that can be used as a food preservative. Due to its antimicrobial activity, it can be used to control Listeria monocytogenes in food; however, the antimicrobial mechanism of nisin ...

  18. ANÁLISIS ESTRUCTURAL DE FILETES SAJADOS DE HÍBRIDO DE CACHAMA Piaractus braquypomus x Colossoma macropomum UTILIZANDO BACTERIOCINAS PRODUCIDAS POR Lactobacillus plantarum LPBM10 EMPACADO AL VACÍO

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    Héctor Suárez M

    2008-08-01

    Full Text Available Objective. To determine microstructure, texture and sensory changes in cut cachama hybrid fillets. Materials and methods. Hybrid fillets that were vacuum packed for 30 days at 3°C were analyzed after preservative treatments by crude bacteriocins extract, lactic acid, and control by light microscopy. Results. Space among the muscle fibers increased gradually and the architectural arrangement was altered in all treatments throughout the entire storage period. The lowest alteration in connective tissue degradation and lowest increment in spaces between the muscular fibers was observed with the crude bacteriocin extract treatment. The instrumental textural analysis showed no statistical difference in the stability loss of tissues from fillets among treatments. Sensory analysis indicated that the lancing treatment was effective in diminishing the negative effect of intramuscular bones. The best scores were for cutting fillets with the bacteriocin treatment. Conclusions. The meat texture of fillets was affected during the storage period. Lancing is a procedure that enables the use of fillets without encountering the intramuscular bone problem. The use of crude bacteriocins extract prolongs the shelf-life of fillets.

  19. POTENTIAL OF Lactococcus lactis subsp. lactis MTCC 3041 AS A BIOPRESERVATIVE

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    Neha Sharma

    2013-10-01

    Full Text Available Lactic acid bacteria especially in developing countries can be exploited against frequently occurring spoilage organisms of fresh fruits and vegetables in addition to pathogens. Keeping in views this antagonism imparted by bacteria Lactococci, the present study was taken and effectiveness of bacteriocin of Lactococci was also studied in preservatives and enzymes. Lactic acid bacteria Lactococcus lactis subs. Lactis MTCC 3041 was used as bacteriocin producer strain. Isolation of most frequently occurring spoilage organisms from spoiled Mango and Kinnow was done by microbiological procedures and were identified by microscopic studies as Isolate 1 and Isolate 2. It has limited use in processed salted food as no zone of inhibition was observed at and above 5% NaCl (w/v.0.3% (w/v is the minimum concentration of KMS that provides stress to the microorganism for the production of bacteriocin. It is not suitable for food having sodium benzoate as preservative as with increase in concentration growth of Lactococcus lactis decreases. Presence of bacteriocin hinders the growth of the isolate 1 as fresh weight of the mycelium in test sample is 7.09% less than the control. Being non-pathogenic this organism can be safely used against spoilage organisms in addition to food borne pathogens.

  20. ANTILISTERIAL ACTYVITY OF LACTIC ACID BACTERIA ISOLATED FROM GILTHEAD BREAMS AND SEA BASSES FILLETS PACKAGED MAP AGAINST PRIMITIVE STRAINS OF LISTERIA MONOCYTOGENES

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    M. Barile

    2011-04-01

    Full Text Available Listeria monocytogenes is the causative agent of listeriosis typically caused by ready-to-eat processed food that have a refrigerated shelf-life, but lightly preserved fish products also belong to a high-risk category. Aim of the work was to evaluate antimicrobial activity linked bacteriocin-producing of LAB isolated from gilthead breams and sea basses fillets packaged in modified atmospheres. Fifty-five LAB strains were screened against 21 strains of Listeria monocytogenes, 1 Listeria innocua held in the culture collection of Department of Zootechnical Sciences and Food Ispection (SIA and submitted to antagonistic activity using the spot on lawn and the agar well diffusion assay. Lactococcus lactis sub. lactis Sa31 was able to produce bacteriocin in agar and different broth medium. The bacteriocin man31 showed sensitivity to trypsin, pronase E and papain, inactivation at temperatures ≥ 100°C, bactericidal mode of action and antilisterial act, rapidly. The bacteriocin man31 caused a reduction of L. monocytogenes ½ c growth about log10 > 3 UFC/ml, when was applied on indicator strain at 20,480 AU/ml concentration, in vitro.