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Bonita A. Glatz - One of the best experts on this subject based on the ideXlab platform.
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Detection of the bacteriocin propionicin PLG-1 with polyvalent anti-PLG-1 antiserum.
Applied and environmental microbiology, 2001Co-Authors: Jay A. Leversee, Bonita A. GlatzAbstract:Polyclonal antibodies against the bacteriocin propionicin PLG-1 were produced in rabbits at high titer (256,000 to 512,000, as determined by indirect enzyme-linked immunosorbent assay [ELISA]). Anti-PLG-1 antiserum neutralized the antimicrobial activity of PLG-1 preparations in a well diffusion assay. Cross-reacting protein was detected using an indirect ELISA of the culture supernatant from a fed-batch fermentation of the producer strain Propionibacterium thoenii P127 within the first 24 h of incubation, but bacteriocin activity was not detected in the same culture until 217 h of incubation. Culture supernatants from 156 strains of classical dairy propionibacteria were tested by indirect ELISA at 5 and 12 days of incubation for production of cross-reacting protein and by well diffusion assay for bacteriocin activity. Cross-reacting protein was detected in 52 strains: all of the tested strains of P. thoenii, most of the strains of Propionibacterium jensenii, and a minority of the Propionibacterium acidipropionici and Propionibacterium freudenreichii strains. Of these 52 strains, only 4 strains of P. thoenii showed bacteriocin activity in a well diffusion assay. Eight bacteriocin-negative mutants of strain P127 were negative in both ELISA and well diffusion assays. Western blot analysis showed that three protein bands bound anti-PLG-1 antibodies in culture supernatants: a 9.1-kDa band that is assumed to be the PLG-1 monomer and 16.2- and 27.5-kDa bands that may be precursors, multimers, or complexes of PLG-1.
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Response of cultures of Propionibacterium to acid and low pH: tolerance and inhibition.
Journal of food protection, 1998Co-Authors: Jill Louise Rehberger, Bonita A. GlatzAbstract:Seventeen Propionibacterium strains were tested for acid production and final pH achieved on glucose, fructose, or maltose as the primary carbon source. On average, strains of Propionibacterium acidipropionici produced more acid and reached lower final pH values than did strains of the other species. Three strains of P acidipropionici, one Propionibacterium jensenii, and two Propionibacterium thoenii strains were tested further for the ability to survive and/or grow at low pH with lactic, hydrochloric, or propionic acid as acidulant. The organic acids were more inhibitory than hydrochloric acid; propionic acid was most inhibitory. In all cases, the P. jensenii and P. thoenii strains initiated growth and survived at lower pH values than did the P. acidipropionici strains. The ability to produce large amounts of acid or achieve low final pH values did not coincide with the ability to initiate growth or survive in low-pH conditions. Strains could not initiate growth below pH 5.0, but cultures started at neutral pH reached final pH values of less than 4.4. At neutral pH, strains could grow in the presence of increased lactate concentrations (up to 180 mM) or propionate concentrations (150 mM) that were inhibitory at acid pH. Attempts to isolate variants able to initiate growth below pH 5.0 were unsuccessful.
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Enhanced Bacteriocin Production by Propionibacterium thoenii in Fed-Batch Fermentation ‡.
Journal of food protection, 1997Co-Authors: Hyun-dong Paik, Bonita A. GlatzAbstract:Synthesis of the bacteriocin propionicin PLG-1 as well as culture growth and organic acid production by Propionibacterium thaenii P127 were followed in fed-batch fermentations conducted for 504 h in a sodium lactate broth. Average concentrations of viable cells were higher in two small-scale fed-batch fermentations than in batch fermentations: 2.2 × 109 cells per ml versus 3.7 × 108 cells per ml. Propionic acid concentration averaged 35.8 g/liter at the end of fed-batch fementation, and maximum bacteriocin titers were 184 and 146 AU/ml in the two fed-batch fermentations. After reaching the maximum value, bacteriocin activity dropped sharply upon continued incubation. Large quantities of propionicin PLG-I could be obtained in large-scale fed-batch fermentation, but the concentration (100 AU/ml) was lower than in the small-scale fermentations. Fed-batch fermentation shows promise as a method to obtain high concentrations of bacteriocin from the propionibacteria.
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enhanced bacteriocin production by Propionibacterium thoenii in fed batch fermentation
Journal of Food Protection, 1997Co-Authors: Hyun-dong Paik, Bonita A. GlatzAbstract:Synthesis of the bacteriocin propionicin PLG-1 as well as culture growth and organic acid production by Propionibacterium thaenii P127 were followed in fed-batch fermentations conducted for 504 h in a sodium lactate broth. Average concentrations of viable cells were higher in two small-scale fed-batch fermentations than in batch fermentations: 2.2 × 109 cells per ml versus 3.7 × 108 cells per ml. Propionic acid concentration averaged 35.8 g/liter at the end of fed-batch fementation, and maximum bacteriocin titers were 184 and 146 AU/ml in the two fed-batch fermentations. After reaching the maximum value, bacteriocin activity dropped sharply upon continued incubation. Large quantities of propionicin PLG-I could be obtained in large-scale fed-batch fermentation, but the concentration (100 AU/ml) was lower than in the small-scale fermentations. Fed-batch fermentation shows promise as a method to obtain high concentrations of bacteriocin from the propionibacteria.
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Improvement of detection and production of propionicin PLG-1, a bacteriocin produced by Propionibacterium thoenii
Journal of food protection, 1996Co-Authors: Hsing-yi Hsieh, Hyun-dong Paik, Bonita A. GlatzAbstract:Propionibacterium thoenii P127 produces propionicin PLG-1 in liquid culture at relatively low concentrations and slow production rates. The goal of this study was to increase the sensitivity and reproducibility of the standard well-diffusion assay for bacteriocin activity as well as to improve production of propionicin PLG-1 under controlled conditions in a fermenter. Several conditions were varied in the well-diffusion assay. The best results were obtained with 7-mm wells cut into a 5-mm-deep base layer that contained 2.5% agar, 0.85% NaCl and 0.1 % Tween 80. Plates were incubated at room temperature for 24 h or at 37°C for 2 h before adding bacteriocin samples to the wells to aid diffusion. Larger and clearer zones of inhibition were observed when Lactobacillus delbrueckii ATCC 4797 rather than Propionibacterium acidipropionici P5 was used as indicator strain, and results could be read in 12 h. Recovery of bacteriocin from the culture supernatant was improved by adding 0.1% Tween 80 to the buffer used for dialysis and resuspension of precipitated protein. Strain P127 was grown in six different media under controlled conditions in a fermenter: 12.5% beet molasses; 9% corn steep liquor; combinations of beet molasses and corn steep liquor at 1:3, 1:1, and 3:1 (vol:vol) ratios; and the standard growth medium, sodium lactate broth. Maximum production of propionicin PLG-1 was obtained in 3:1 beet molasses:corn steep liquor, and was 5 times greater than in sodium lactate broth.
Helge Holo - One of the best experts on this subject based on the ideXlab platform.
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Ruminal survival of Propionibacterium thoenii T159 in dairy cows at high feed intake
Acta Agriculturae Scandinavica Section A — Animal Science, 2020Co-Authors: Jikun Chen, Helge Holo, Angela Schwarm, Odd Magne HarstadAbstract:Propionibacterium thoenii strain T159 (5 × 1011 CFU) were administered daily in the rumen of four Norwegian Red dairy cows. Total Propionibacterium in the rumen were substantially increased during ...
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Using strains of Propionibacteria to mitigate methane emissions in vitro
Acta Agriculturae Scandinavica Section A - Animal Science, 2012Co-Authors: A. Y. Alazzeh, Helge Holo, Odd Magne Harstad, Halima Sultana, Karen A. Beauchemin, Yanan Wang, Tim A. McallisterAbstract:Abstract Sixteen strains of propionibacteria were inoculated into in vitro ruminal incubations to evaluate their potential to reduce methane (CH4) production from concentrate and forage diets. Propionibacterium freudenreichii T114, Propionibacterium thoenii T159, and Propionibacterium thoenii ATCC 4874 lowered (p < 0.05) CH4 production from both substrates compared to control. Compared to control, Propionibacterium jensenii T1, Propionibacterium freudenreichii T31, and Propionibacterium freudenreichii T54 lowered (p < 0.05) CH4 production only with corn. Propionibacterium propionicus T83 caused higher (p < 0.05) propionate percentage and lower (p < 0.05) acetate:propionate than the control with corn; however, this did not result in a decline in CH4 production. Results demonstrate that some strains of propionibacteria have the potential to lower CH4 production from mixed ruminal cultures and that this reduction is not always associated with an increase in propionate production.
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Heterologous production of antimicrobial peptides in Propionibacterium freudenreichii.
Applied and environmental microbiology, 2005Co-Authors: Dag Anders Brede, Therese Faye, Ingolf F. Nes, Melanie P. Stierli, Gottfried Dasen, Anita Theiler, Leo Meile, Helge HoloAbstract:Heterologous bacteriocin production in Propionibacterium freudenreichii is described. We developed an efficient system for DNA shuttling between Escherichia coli and P. freudenreichii using vector pAMT1. It is based on the P. freudenreichii rolling-circle replicating plasmid pLME108 and carries the cml(A)/cmx(A) chloramphenicol resistance marker. Introduction of the propionicin T1 structural gene (pctA) into pAMT1 under the control of the constitutive promoter (P4) yielded bacteriocin in amounts equal to those of the wild-type producer Propionibacterium thoenii 419. The P. freudenreichii clone showed propionicin T1 activity in coculture, killing 90% of sensitive bacteria within 48 h. The pamA gene from P. thoenii 419 encoding the protease-activated antimicrobial peptide (PAMP) was cloned and expressed in P. freudenreichii, resulting in secretion of the pro-PAMP protein. Like in the wild type, PAMP activation was dependent on externally added protease. Secretion of the antimicrobial peptide was obtained from a clone in which the pamA signal peptide and PAMP were fused in frame. The promoter region of pamA was identified by fusion of putative promoter fragments to the coding sequence of the pctA gene. The P4 and Ppamp promoters directed constitutive gene expression, and activity of both promoters was enhanced by elements upstream of the promoter core region.
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Prevalence of the Genes Encoding Propionicin T1 and Protease-Activated Antimicrobial Peptide and Their Expression in Classical Propionibacteria
Applied and environmental microbiology, 2004Co-Authors: Therese Faye, Thor Langsrud, Ingolf F. Nes, Dag Anders Brede, Helge HoloAbstract:The purpose of this study was to investigate the frequency of production of the bacteriocin propionicin T1 and the protease-activated antimicrobial peptide (PAMP) and their corresponding genes in 64 isolates of classical propionibacteria. This study revealed that these genes are widespread in Propionibacterium jensenii and Propionibacterium thoenii but absent from the remaining species of classical propionibacteria that were studied. The pro-PAMP-encoding gene (pamA) was found in 63% of the P. jensenii strains and 61% of the P. thoenii strains, and all of these strains displayed PAMP activity. The propionicin T1-encoding gene (pctA) was present in 89% of the P. thoenii strains and 54% of the P. jensenii strains. All P. thoenii strains containing the pctA gene exhibited antimicrobial activity corresponding to propionicin T1 activity, whereas only 38% of the pctA-containing P. jensenii strains displayed this activity. Sequencing of the pctA genes revealed the existence of two allelic variants that differed in a single nucleotide in six strains of P. jensenii; in these strains the glycine at position 55 of propionicin T1 was replaced by an aspartate residue (A variant). No strains harboring the A variant showed any antimicrobial activity against propionicin T1-sensitive bacteria. An open reading frame (orf2) located immediately downstream from the pctA gene was absent in three strains containing the G variant of propionicin T1. Two of these strains showed low antimicrobial activity, while the third strain showed no antimicrobial activity at all. The protein encoded by orf2 showed strong homology to ABC transporters, and it has been proposed previously that this protein is involved in the producer immunity against propionicin T1. The limited antimicrobial activity exhibited by the strains lacking orf2 further suggests that this putative ABC transporter plays an important role in propionicin T1 activity.
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Biochemical and genetic characterization of propionicin T1, a new bacteriocin from Propionibacterium thoenii.
Applied and environmental microbiology, 2000Co-Authors: Therese Faye, Thor Langsrud, Ingolf F. Nes, Helge HoloAbstract:A collection of propionibacteria was screened for bacteriocin production. A new bacteriocin named propionicin T1 was isolated from two strains of Propionibacterium thoenii. This bacteriocin shows no sequence similarity to other bacteriocins. Propionicin T1 was active against all strains of Propionibacterium acidipropionici, Propionibacterium thoenii, and Propionibacterium jensenii tested and also against Lactobacillus sake NCDO 2714 but showed no activity against Propionibacterium freudenreichii. The bacteriocin was purified, and the N-terminal part of the peptide was determined with amino acid sequencing. The corresponding gene pctA was sequenced, and this revealed that propionicin T1 is produced as a prebacteriocin of 96 amino acids with a typical sec leader, which is processed to give a mature bacteriocin of 65 amino acids. An open reading frame encoding a protein of 424 amino acids was found 68 nucleotides downstream the stop codon of pctA. The N-terminal part of this putative protein shows strong similarity with the ATP-binding cassette of prokaryotic and eukaryotic ABC transporters, and this protein may be involved in self-protection against propionicin T1. Propionicin T1 is the first bacteriocin from propionibacteria that has been isolated and further characterized at the molecular level.
Yavuz Beyatli - One of the best experts on this subject based on the ideXlab platform.
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acid bile antibiotic resistance and inhibitory properties of propionibacteria isolated from turkish traditional home made cheeses
Anaerobe, 2012Co-Authors: Derya Onal Darilmaz, Yavuz BeyatliAbstract:In this study, a total of 29 Propionibacterium spp. were isolated from traditional home-made Turkish cheese samples. As a result of the identification, isolates were identified as Propionibacterium freudenreichii subsp. freudenreichii (15 strains), Propionibacterium jensenii (12), and Propionibacterium thoenii (2). All isolates and 5 reference strains were examined for their abilities to survive at pH 2.0, 3.0, 4.0, 5.0 and in the presence of 0.06, 0.15 and 0.30% bile salts, their influence on the growth of food-borne and spoilage bacteria, as well as their sensitivity against 11 selected antibiotics. Only seven propionibacteria strains survived in both the acidic and bile salt environments. Propionibacterium spp. strains strongly inhibited growth of the Escherichia coli ATCC 11229 and Shigella sonnei Mu:57 strains (91%). All propionibacteria strains were sensitive to a majority of the antibiotics used in the investigations. Overall, dairy propionibacteria showed high antibacterial activity, resistance to pH 4.0, 5.0, high resistance to bile salts and will provide an alternative source to Lactobacillus and Bifidobacterium as probiotic culture.
Therese Faye - One of the best experts on this subject based on the ideXlab platform.
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Heterologous production of antimicrobial peptides in Propionibacterium freudenreichii.
Applied and environmental microbiology, 2005Co-Authors: Dag Anders Brede, Therese Faye, Ingolf F. Nes, Melanie P. Stierli, Gottfried Dasen, Anita Theiler, Leo Meile, Helge HoloAbstract:Heterologous bacteriocin production in Propionibacterium freudenreichii is described. We developed an efficient system for DNA shuttling between Escherichia coli and P. freudenreichii using vector pAMT1. It is based on the P. freudenreichii rolling-circle replicating plasmid pLME108 and carries the cml(A)/cmx(A) chloramphenicol resistance marker. Introduction of the propionicin T1 structural gene (pctA) into pAMT1 under the control of the constitutive promoter (P4) yielded bacteriocin in amounts equal to those of the wild-type producer Propionibacterium thoenii 419. The P. freudenreichii clone showed propionicin T1 activity in coculture, killing 90% of sensitive bacteria within 48 h. The pamA gene from P. thoenii 419 encoding the protease-activated antimicrobial peptide (PAMP) was cloned and expressed in P. freudenreichii, resulting in secretion of the pro-PAMP protein. Like in the wild type, PAMP activation was dependent on externally added protease. Secretion of the antimicrobial peptide was obtained from a clone in which the pamA signal peptide and PAMP were fused in frame. The promoter region of pamA was identified by fusion of putative promoter fragments to the coding sequence of the pctA gene. The P4 and Ppamp promoters directed constitutive gene expression, and activity of both promoters was enhanced by elements upstream of the promoter core region.
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Prevalence of the Genes Encoding Propionicin T1 and Protease-Activated Antimicrobial Peptide and Their Expression in Classical Propionibacteria
Applied and environmental microbiology, 2004Co-Authors: Therese Faye, Thor Langsrud, Ingolf F. Nes, Dag Anders Brede, Helge HoloAbstract:The purpose of this study was to investigate the frequency of production of the bacteriocin propionicin T1 and the protease-activated antimicrobial peptide (PAMP) and their corresponding genes in 64 isolates of classical propionibacteria. This study revealed that these genes are widespread in Propionibacterium jensenii and Propionibacterium thoenii but absent from the remaining species of classical propionibacteria that were studied. The pro-PAMP-encoding gene (pamA) was found in 63% of the P. jensenii strains and 61% of the P. thoenii strains, and all of these strains displayed PAMP activity. The propionicin T1-encoding gene (pctA) was present in 89% of the P. thoenii strains and 54% of the P. jensenii strains. All P. thoenii strains containing the pctA gene exhibited antimicrobial activity corresponding to propionicin T1 activity, whereas only 38% of the pctA-containing P. jensenii strains displayed this activity. Sequencing of the pctA genes revealed the existence of two allelic variants that differed in a single nucleotide in six strains of P. jensenii; in these strains the glycine at position 55 of propionicin T1 was replaced by an aspartate residue (A variant). No strains harboring the A variant showed any antimicrobial activity against propionicin T1-sensitive bacteria. An open reading frame (orf2) located immediately downstream from the pctA gene was absent in three strains containing the G variant of propionicin T1. Two of these strains showed low antimicrobial activity, while the third strain showed no antimicrobial activity at all. The protein encoded by orf2 showed strong homology to ABC transporters, and it has been proposed previously that this protein is involved in the producer immunity against propionicin T1. The limited antimicrobial activity exhibited by the strains lacking orf2 further suggests that this putative ABC transporter plays an important role in propionicin T1 activity.
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Biochemical and genetic characterization of propionicin T1, a new bacteriocin from Propionibacterium thoenii.
Applied and environmental microbiology, 2000Co-Authors: Therese Faye, Thor Langsrud, Ingolf F. Nes, Helge HoloAbstract:A collection of propionibacteria was screened for bacteriocin production. A new bacteriocin named propionicin T1 was isolated from two strains of Propionibacterium thoenii. This bacteriocin shows no sequence similarity to other bacteriocins. Propionicin T1 was active against all strains of Propionibacterium acidipropionici, Propionibacterium thoenii, and Propionibacterium jensenii tested and also against Lactobacillus sake NCDO 2714 but showed no activity against Propionibacterium freudenreichii. The bacteriocin was purified, and the N-terminal part of the peptide was determined with amino acid sequencing. The corresponding gene pctA was sequenced, and this revealed that propionicin T1 is produced as a prebacteriocin of 96 amino acids with a typical sec leader, which is processed to give a mature bacteriocin of 65 amino acids. An open reading frame encoding a protein of 424 amino acids was found 68 nucleotides downstream the stop codon of pctA. The N-terminal part of this putative protein shows strong similarity with the ATP-binding cassette of prokaryotic and eukaryotic ABC transporters, and this protein may be involved in self-protection against propionicin T1. Propionicin T1 is the first bacteriocin from propionibacteria that has been isolated and further characterized at the molecular level.
Wanda J. Lyon - One of the best experts on this subject based on the ideXlab platform.
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Inhibition of psychrotrophic organisms by propionicin PLG-1, a bacteriocin produced by Propionibacterium thoenii.
Journal of dairy science, 1993Co-Authors: Wanda J. Lyon, Joyce K. Sethi, Bonita A. GlatzAbstract:Propionibacterium thoenii strain P127, which produces the bacteriocin propionicin PLG-1, was grown in a skim milk medium and produced bacteriocin in that medium. No bacteriocin activity was detected in skim milk medium in which strain P127-1, a bacteriocin-negative variant of strain P127, had been grown. Five psychrotrophic spoilage or pathogenic organisms (one strain each of Listeria monocytogenes, Pseudomonas fluorescens, Vibrio parahaemolyticus, Yersinia enterocolitica, and one strain of Corynebacterium sp.) were incubated for 24 h in laboratory medium, nonfermented skim milk, and skim milk that had been fermented by strain P127 or P127-1. Strains were inhibited only in the skim milk fermented by strain P127, as evidenced by loss in numbers of viable cells after 24 h at 10 degrees C and less growth than in other media after 24 h at optimal growth temperatures. Growth of selected strains was delayed or slowed during prolonged incubation (21 d) at 10 degrees C. Propionicin PLG-1 shows promise as a preservative for food products.
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Isolation and purification of propionicin PLG-1, a bacteriocin produced by a strain of Propionibacterium thoenii.
Applied and environmental microbiology, 1993Co-Authors: Wanda J. Lyon, Bonita A. GlatzAbstract:Production of propionicin PLG-1 by Propionibacterium thoenii P127 was pH dependent, with maximal activity detected in supernatants of cultures grown at pH 7.0 Propionicin PLG-1 was purified by ion-exchange chromatography and isoelectric focusing. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of propionicin PLG-1 purified through isoelectric focusing resolved a protein band with a molecular weight of 10,000. Propionicin PLG-1 was bactericidal to sensitive cells, demonstrating single-hit kinetics. The producing strain harbored a single plasmid (pLG1) with an approximate size of 250 kb. Preliminary data indicate that both propionicin PLG-1 and immunity to the bacteriocin are encoded on the chromosome. Exposure of strain P127 to acriflavine or to N-methyl-N9-nitro-N-nitrosoguanidine yielded isolates that no longer produced bacteriocin activity and isolates that were cured of the plasmid. However, loss of bacteriocin production was not correlated with loss of the plasmid. Isolates cured of the plasmid were phenotypically identical to plasmid-bearing cells in fermentation patterns, pigment production, and growth characteristics. Images
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Partial purification and characterization of a bacteriocin produced by Propionibacterium thoenii
Applied and environmental microbiology, 1991Co-Authors: Wanda J. Lyon, Bonita A. GlatzAbstract:A partially purified bacteriocin produced by Propionibacterium thoenii designated propionicin PLG-1 was found to be active against closely related species and exhibited a broad spectrum of activity against other microorganisms. Propionicin PLG-1 was found to be heat labile, sensitive to several proteolytic enzymes, and stable at pH 3 to 9. Propionicin PLG-1 was isolated from solid medium, partially purified by ammonium sulfate precipitation, and purified further by gel filtration. Gel filtration experiments revealed that bacteriocin PLG-1 was present as two different protein aggregates with apparent molecular weights of more than 150,000 and approximately 10,000. Resolution of these protein aggregates by sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed the presence of a protein common to both with an apparent molecular weight of 10,000.
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Characterization and isolation of a bacteriocin produced by a strain of Propionibacterium thoenii
1Co-Authors: Wanda J. LyonAbstract:A partially purified bacteriocin produced by Propionibacterium thoenii designated propionicin PLG-1 was found to be active against closely related species and exhibited a broad spectrum of activity against other microorganisms. Propionicin PLG-1 was found to be heat-labile, sensitive to several proteolytic enzymes, and stable at pH 3-9. Propionicin PLG-1 was isolated from solid medium, partially purified by ammonium sulfate precipitation, and purified further by gel filtration. Gel filtration experiments revealed that the bacteriocin PLG-1 was present as two different protein aggregates with apparent molecular weights greater than 150,000 and approximately 10,000. Resolution of these protein aggregates by sodium dodecyl sulfate -polyacrylamide gel electrophoresis revealed the presence of a protein common to both with apparent molecular weight 10,000.
