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Kenji Sonomoto - One of the best experts on this subject based on the ideXlab platform.

  • Nutrition‐adaptive control of multiple‐bacteriocin production by Weissella hellenica QU 13
    Journal of applied microbiology, 2015
    Co-Authors: Yoshimitsu Masuda, Takeshi Zendo, Rodney Horanda Perez, Kenji Sonomoto
    Abstract:

    Aim To analyse nutrition-adaptive multiple-bacteriocin production by Weissella hellenica QU 13. Methods and Results Weissella hellenica QU 13 produces two leaderless bacteriocins, weissellicins Y and M. Their production was studied in MRS and APT media by quantification analyses with liquid chromatography mass spectrometry (LC/MS), while transcriptional analysis of biosynthetic genes was performed by real-time reverse transcription (RT)-PCR. Weissellicin Y production was higher in MRS culture than in APT culture, while weissellicin M production was higher in APT culture than in MRS culture. APT medium contains a higher amount of thiamine than MRS medium, to enhance the growth of heterofermentative lactic acid bacteria. Therefore, thiamine addition to MRS culture enhanced the growth of W. hellenica QU 13; consequently, weissellicin Y production was decreased, while weissellicin M production was not affected. Furthermore, real-time RT-PCR analyses indicated that the transcriptional trends of their respective structural genes, welY and welM, were different from each other, and that these two genes’ transcriptions responded to nutrition conditions. Conclusion Weissella hellenica QU 13 was demonstrated to control weissellicins Y and M production based on nutrition conditions. In addition, differential expression behaviour of weissellicins Y and M indicates that each of them would have separate roles to adapt to different environmental situations. Significance and Impact of the Study This is the first report that describes nutrition-adaptive multiple-bacteriocin production, in which thiamine inhibits bacteriocin production while it enhances the growth of the producer strain.

  • characterization and identification of weissellicin y and weissellicin m novel bacteriocins produced by Weissella hellenica qu 13
    Journal of Applied Microbiology, 2012
    Co-Authors: Yoshimitsu Masuda, Takeshi Zendo, Naruhiko Sawa, Jiro Nakayama, Rodney Perez, Kenji Sonomoto
    Abstract:

    Aims To identify and characterize novel bacteriocins from Weissella hellenica QU 13. Methods and results Weissella hellenica QU 13, isolated from a barrel used to make Japanese pickles, produced two novel bacteriocins termed weissellicin Y and weissellicin M. The primary structures of weissellicins Y and M were determined, and their molecular masses were determined to be 4925·12 and 4968·40 Da, respectively. Analysis of the DNA sequence encoding the bacteriocins revealed that they were synthesized and secreted without N-terminal extensions such as leader sequences or sec signal peptides. Weissellicin M showed significantly high and characteristic homology with enterocins L50A and L50B, produced by Enterococcus faecium L50, while weissellicin Y showed no homology with any other known bacteriocins. Both bacteriocins showed broad antimicrobial spectra, with especially high antimicrobial activity against species, which contaminate pickles, such as Bacillus coagulans, and weissellicin M showed relatively higher activity than weissellicin Y. Furthermore, the stability of weissellicin M against pH and heat was distinctively higher than that of weissellicin Y. Conclusions Weissella hellenica QU 13 produced two novel leaderless bacteriocins, weissellicin Y and weissellicin M, and weissellicin M exhibited remarkable potency that could be employed by pickle-producing industry. Significance and impact of the study This study is the first report, which represents a complete identification and characterization of novel leaderless bacteriocins from Weissella genus.

  • Characterization and identification of weissellicin Y and weissellicin M, novel bacteriocins produced by Weissella hellenica QU 13
    Journal of applied microbiology, 2011
    Co-Authors: Yoshimitsu Masuda, Takeshi Zendo, Naruhiko Sawa, Rodney Horanda Perez, Jiro Nakayama, Kenji Sonomoto
    Abstract:

    To identify and characterize novel bacteriocins from Weissella hellenica QU 13. Weissella hellenica QU 13, isolated from a barrel used to make Japanese pickles, produced two novel bacteriocins termed weissellicin Y and weissellicin M. The primary structures of weissellicins Y and M were determined, and their molecular masses were determined to be 4925·12 and 4968·40 Da, respectively. Analysis of the DNA sequence encoding the bacteriocins revealed that they were synthesized and secreted without N-terminal extensions such as leader sequences or sec signal peptides. Weissellicin M showed significantly high and characteristic homology with enterocins L50A and L50B, produced by Enterococcus faecium L50, while weissellicin Y showed no homology with any other known bacteriocins. Both bacteriocins showed broad antimicrobial spectra, with especially high antimicrobial activity against species, which contaminate pickles, such as Bacillus coagulans, and weissellicin M showed relatively higher activity than weissellicin Y. Furthermore, the stability of weissellicin M against pH and heat was distinctively higher than that of weissellicin Y. Weissella hellenica QU 13 produced two novel leaderless bacteriocins, weissellicin Y and weissellicin M, and weissellicin M exhibited remarkable potency that could be employed by pickle-producing industry. This study is the first report, which represents a complete identification and characterization of novel leaderless bacteriocins from Weissella genus. © 2011 The Authors. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology.

Fujitoshi Yanagida - One of the best experts on this subject based on the ideXlab platform.

  • Distribution and antimicrobial activity of lactic acid bacteria associated with lychee fruits
    Romanian Biotechnological Letters, 2020
    Co-Authors: Lin-hu Nan, Yi-sheng Chen, Min-chin Liao, Fujitoshi Yanagida
    Abstract:

    Lychee is a popular fruit in China and southeastern Asia. Although it is very popular, the microbiota of lactic acid bacteria (LAB) associated with lychee remains poorly described. Lychee samples from seven different markets located in three cities in Taiwan were collected and a total of 104 LAB were isolated. Through RFLP analyses of 16S rDNA and rpoA genes for grouping and 16S rRNA gene sequencing, these isolates were finally divided into 6 groups (A to F). The most common genera of LAB in lychee samples were Weissella and Leuconostoc. Weissella confusa strain E was found to produce a bacteriocin active against Listeria monocytogenes and some other Gram-positive bacteria. Mass spectrometry analysis revealed the bacteriocin mass to be approximately 3426.77 Da, which is different to other known Weissella bacteriocins. In addition, strain MB7 included in the genus Leuconostoc was identified as potential novel species or subspecies on the basis of phylogenetic analysis of 16S rRNA, rpoA and pheS gene sequences. Thus, this is the first report describing the distribution and varieties of LAB associated with lychee fruits. In addition, one potential novel LAB species or subspecies and one potential novel bacteriocin were also reported in this study.

  • weissellicin l a novel bacteriocin from sian sianzih isolated Weissella hellenica 4 7
    Journal of Applied Microbiology, 2013
    Co-Authors: K H Leong, Yi-sheng Chen, Shwu-fen Pan, Y H Lin, Fujitoshi Yanagida
    Abstract:

    Aim To identify and characterize novel bacteriocins from Weissella hellenica 4-7. Methods and results Weissella hellenica 4-7, isolated from the traditional Taiwanese fermented food sian-sianzih (fermented clams), was previously found to produce a bacteriocin active against Listeria monocytogenes and some other Gram-positive bacteria. Bacteriocin activity decreased slightly after autoclaving (121°C for 15 min), but was inactivated by protease K and trypsin. Mass spectrometry analysis revealed the bacteriocin mass to be approximately 3205·6 Da. N-terminal amino acid sequencing yielded a partial sequence, NH2 -KGFLSWASKATSWLVGP, by Edman degradation. The obtained partial sequence showed high homology with leucocin B-TA33a; however, at least two different residues were observed. No identical peptide or protein was found, and this peptide was therefore considered to be a novel bacteriocin produced by W. hellenica 4-7 and termed weissellicin L. Conclusions The findings obtained in the current study suggest a novel bacteriocin produced by W. hellenica 4-7. Significance and impact of the study Bacteriocins from Weissella remain rare, and this study is the second report of a bacteriocin produced by W. hellenica.

  • Weissellicin L, a novel bacteriocin from sian‐sianzih‐isolated Weissella hellenica 4‐7
    Journal of applied microbiology, 2013
    Co-Authors: K.‐h. Leong, Yi-sheng Chen, Y.‐h. Lin, Shwu-fen Pan, Fujitoshi Yanagida
    Abstract:

    To identify and characterize novel bacteriocins from Weissella hellenica 4-7. Weissella hellenica 4-7, isolated from the traditional Taiwanese fermented food sian-sianzih (fermented clams), was previously found to produce a bacteriocin active against Listeria monocytogenes and some other Gram-positive bacteria. Bacteriocin activity decreased slightly after autoclaving (121°C for 15 min), but was inactivated by protease K and trypsin. Mass spectrometry analysis revealed the bacteriocin mass to be approximately 3205·6 Da. N-terminal amino acid sequencing yielded a partial sequence, NH2 -KGFLSWASKATSWLVGP, by Edman degradation. The obtained partial sequence showed high homology with leucocin B-TA33a; however, at least two different residues were observed. No identical peptide or protein was found, and this peptide was therefore considered to be a novel bacteriocin produced by W. hellenica 4-7 and termed weissellicin L. The findings obtained in the current study suggest a novel bacteriocin produced by W. hellenica 4-7. Bacteriocins from Weissella remain rare, and this study is the second report of a bacteriocin produced by W. hellenica. Journal of Applied Microbiology © 2013 The Society for Applied Microbiology.

  • weissellicin 110 a newly discovered bacteriocin from Weissella cibaria 110 isolated from plaa som a fermented fish product from thailand
    Applied and Environmental Microbiology, 2007
    Co-Authors: Sirinat Srionnual, Fujitoshi Yanagida, Lihsiu Lin, Kuangnan Hsiao, Yi-sheng Chen
    Abstract:

    Weissella cibaria 110, isolated from the Thai fermented fish product plaa-som, was found to produce a bacteriocin active against some gram-positive bacteria. Bacteriocin activity was not eliminated by exposure to high temperatures or catalase but was destroyed by exposure to the proteolytic enzymes proteinase K and trypsin. The bacteriocin from W. cibaria 110 was purified, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that the purified bacteriocin contained one protein band that was approximately 2.5 kDa in size. Mass spectrometry analysis showed the mass of the peptide to be approximately 3,487.8 Da. N-terminal amino acid sequence analysis was performed, and 27 amino acids were identified. Because it has no similarity to other known bacteriocins, this bacteriocin was defined as a new bacteriocin and termed weissellicin 110. Lactic acid bacteria (LAB) have long played important roles in food technology. The LAB include a wide variety of cell types with various physiological and biochemical characteristics. The isolation of LAB from milk products, fermented foods, and plants has frequently been reported. The phylogeny of the bacteria classified currently in the genus Weissella was clarified in 1990 (16), and the taxonomy of Weissella species was further assessed in 1993 (5). Weissella species have been

Yoshimitsu Masuda - One of the best experts on this subject based on the ideXlab platform.

  • Nutrition‐adaptive control of multiple‐bacteriocin production by Weissella hellenica QU 13
    Journal of applied microbiology, 2015
    Co-Authors: Yoshimitsu Masuda, Takeshi Zendo, Rodney Horanda Perez, Kenji Sonomoto
    Abstract:

    Aim To analyse nutrition-adaptive multiple-bacteriocin production by Weissella hellenica QU 13. Methods and Results Weissella hellenica QU 13 produces two leaderless bacteriocins, weissellicins Y and M. Their production was studied in MRS and APT media by quantification analyses with liquid chromatography mass spectrometry (LC/MS), while transcriptional analysis of biosynthetic genes was performed by real-time reverse transcription (RT)-PCR. Weissellicin Y production was higher in MRS culture than in APT culture, while weissellicin M production was higher in APT culture than in MRS culture. APT medium contains a higher amount of thiamine than MRS medium, to enhance the growth of heterofermentative lactic acid bacteria. Therefore, thiamine addition to MRS culture enhanced the growth of W. hellenica QU 13; consequently, weissellicin Y production was decreased, while weissellicin M production was not affected. Furthermore, real-time RT-PCR analyses indicated that the transcriptional trends of their respective structural genes, welY and welM, were different from each other, and that these two genes’ transcriptions responded to nutrition conditions. Conclusion Weissella hellenica QU 13 was demonstrated to control weissellicins Y and M production based on nutrition conditions. In addition, differential expression behaviour of weissellicins Y and M indicates that each of them would have separate roles to adapt to different environmental situations. Significance and Impact of the Study This is the first report that describes nutrition-adaptive multiple-bacteriocin production, in which thiamine inhibits bacteriocin production while it enhances the growth of the producer strain.

  • characterization and identification of weissellicin y and weissellicin m novel bacteriocins produced by Weissella hellenica qu 13
    Journal of Applied Microbiology, 2012
    Co-Authors: Yoshimitsu Masuda, Takeshi Zendo, Naruhiko Sawa, Jiro Nakayama, Rodney Perez, Kenji Sonomoto
    Abstract:

    Aims To identify and characterize novel bacteriocins from Weissella hellenica QU 13. Methods and results Weissella hellenica QU 13, isolated from a barrel used to make Japanese pickles, produced two novel bacteriocins termed weissellicin Y and weissellicin M. The primary structures of weissellicins Y and M were determined, and their molecular masses were determined to be 4925·12 and 4968·40 Da, respectively. Analysis of the DNA sequence encoding the bacteriocins revealed that they were synthesized and secreted without N-terminal extensions such as leader sequences or sec signal peptides. Weissellicin M showed significantly high and characteristic homology with enterocins L50A and L50B, produced by Enterococcus faecium L50, while weissellicin Y showed no homology with any other known bacteriocins. Both bacteriocins showed broad antimicrobial spectra, with especially high antimicrobial activity against species, which contaminate pickles, such as Bacillus coagulans, and weissellicin M showed relatively higher activity than weissellicin Y. Furthermore, the stability of weissellicin M against pH and heat was distinctively higher than that of weissellicin Y. Conclusions Weissella hellenica QU 13 produced two novel leaderless bacteriocins, weissellicin Y and weissellicin M, and weissellicin M exhibited remarkable potency that could be employed by pickle-producing industry. Significance and impact of the study This study is the first report, which represents a complete identification and characterization of novel leaderless bacteriocins from Weissella genus.

  • Characterization and identification of weissellicin Y and weissellicin M, novel bacteriocins produced by Weissella hellenica QU 13
    Journal of applied microbiology, 2011
    Co-Authors: Yoshimitsu Masuda, Takeshi Zendo, Naruhiko Sawa, Rodney Horanda Perez, Jiro Nakayama, Kenji Sonomoto
    Abstract:

    To identify and characterize novel bacteriocins from Weissella hellenica QU 13. Weissella hellenica QU 13, isolated from a barrel used to make Japanese pickles, produced two novel bacteriocins termed weissellicin Y and weissellicin M. The primary structures of weissellicins Y and M were determined, and their molecular masses were determined to be 4925·12 and 4968·40 Da, respectively. Analysis of the DNA sequence encoding the bacteriocins revealed that they were synthesized and secreted without N-terminal extensions such as leader sequences or sec signal peptides. Weissellicin M showed significantly high and characteristic homology with enterocins L50A and L50B, produced by Enterococcus faecium L50, while weissellicin Y showed no homology with any other known bacteriocins. Both bacteriocins showed broad antimicrobial spectra, with especially high antimicrobial activity against species, which contaminate pickles, such as Bacillus coagulans, and weissellicin M showed relatively higher activity than weissellicin Y. Furthermore, the stability of weissellicin M against pH and heat was distinctively higher than that of weissellicin Y. Weissella hellenica QU 13 produced two novel leaderless bacteriocins, weissellicin Y and weissellicin M, and weissellicin M exhibited remarkable potency that could be employed by pickle-producing industry. This study is the first report, which represents a complete identification and characterization of novel leaderless bacteriocins from Weissella genus. © 2011 The Authors. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology.

Takeshi Zendo - One of the best experts on this subject based on the ideXlab platform.

  • Nutrition‐adaptive control of multiple‐bacteriocin production by Weissella hellenica QU 13
    Journal of applied microbiology, 2015
    Co-Authors: Yoshimitsu Masuda, Takeshi Zendo, Rodney Horanda Perez, Kenji Sonomoto
    Abstract:

    Aim To analyse nutrition-adaptive multiple-bacteriocin production by Weissella hellenica QU 13. Methods and Results Weissella hellenica QU 13 produces two leaderless bacteriocins, weissellicins Y and M. Their production was studied in MRS and APT media by quantification analyses with liquid chromatography mass spectrometry (LC/MS), while transcriptional analysis of biosynthetic genes was performed by real-time reverse transcription (RT)-PCR. Weissellicin Y production was higher in MRS culture than in APT culture, while weissellicin M production was higher in APT culture than in MRS culture. APT medium contains a higher amount of thiamine than MRS medium, to enhance the growth of heterofermentative lactic acid bacteria. Therefore, thiamine addition to MRS culture enhanced the growth of W. hellenica QU 13; consequently, weissellicin Y production was decreased, while weissellicin M production was not affected. Furthermore, real-time RT-PCR analyses indicated that the transcriptional trends of their respective structural genes, welY and welM, were different from each other, and that these two genes’ transcriptions responded to nutrition conditions. Conclusion Weissella hellenica QU 13 was demonstrated to control weissellicins Y and M production based on nutrition conditions. In addition, differential expression behaviour of weissellicins Y and M indicates that each of them would have separate roles to adapt to different environmental situations. Significance and Impact of the Study This is the first report that describes nutrition-adaptive multiple-bacteriocin production, in which thiamine inhibits bacteriocin production while it enhances the growth of the producer strain.

  • characterization and identification of weissellicin y and weissellicin m novel bacteriocins produced by Weissella hellenica qu 13
    Journal of Applied Microbiology, 2012
    Co-Authors: Yoshimitsu Masuda, Takeshi Zendo, Naruhiko Sawa, Jiro Nakayama, Rodney Perez, Kenji Sonomoto
    Abstract:

    Aims To identify and characterize novel bacteriocins from Weissella hellenica QU 13. Methods and results Weissella hellenica QU 13, isolated from a barrel used to make Japanese pickles, produced two novel bacteriocins termed weissellicin Y and weissellicin M. The primary structures of weissellicins Y and M were determined, and their molecular masses were determined to be 4925·12 and 4968·40 Da, respectively. Analysis of the DNA sequence encoding the bacteriocins revealed that they were synthesized and secreted without N-terminal extensions such as leader sequences or sec signal peptides. Weissellicin M showed significantly high and characteristic homology with enterocins L50A and L50B, produced by Enterococcus faecium L50, while weissellicin Y showed no homology with any other known bacteriocins. Both bacteriocins showed broad antimicrobial spectra, with especially high antimicrobial activity against species, which contaminate pickles, such as Bacillus coagulans, and weissellicin M showed relatively higher activity than weissellicin Y. Furthermore, the stability of weissellicin M against pH and heat was distinctively higher than that of weissellicin Y. Conclusions Weissella hellenica QU 13 produced two novel leaderless bacteriocins, weissellicin Y and weissellicin M, and weissellicin M exhibited remarkable potency that could be employed by pickle-producing industry. Significance and impact of the study This study is the first report, which represents a complete identification and characterization of novel leaderless bacteriocins from Weissella genus.

  • Characterization and identification of weissellicin Y and weissellicin M, novel bacteriocins produced by Weissella hellenica QU 13
    Journal of applied microbiology, 2011
    Co-Authors: Yoshimitsu Masuda, Takeshi Zendo, Naruhiko Sawa, Rodney Horanda Perez, Jiro Nakayama, Kenji Sonomoto
    Abstract:

    To identify and characterize novel bacteriocins from Weissella hellenica QU 13. Weissella hellenica QU 13, isolated from a barrel used to make Japanese pickles, produced two novel bacteriocins termed weissellicin Y and weissellicin M. The primary structures of weissellicins Y and M were determined, and their molecular masses were determined to be 4925·12 and 4968·40 Da, respectively. Analysis of the DNA sequence encoding the bacteriocins revealed that they were synthesized and secreted without N-terminal extensions such as leader sequences or sec signal peptides. Weissellicin M showed significantly high and characteristic homology with enterocins L50A and L50B, produced by Enterococcus faecium L50, while weissellicin Y showed no homology with any other known bacteriocins. Both bacteriocins showed broad antimicrobial spectra, with especially high antimicrobial activity against species, which contaminate pickles, such as Bacillus coagulans, and weissellicin M showed relatively higher activity than weissellicin Y. Furthermore, the stability of weissellicin M against pH and heat was distinctively higher than that of weissellicin Y. Weissella hellenica QU 13 produced two novel leaderless bacteriocins, weissellicin Y and weissellicin M, and weissellicin M exhibited remarkable potency that could be employed by pickle-producing industry. This study is the first report, which represents a complete identification and characterization of novel leaderless bacteriocins from Weissella genus. © 2011 The Authors. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology.

Wu Ming Yang - One of the best experts on this subject based on the ideXlab platform.

  • first description of a novel Weissella species as an opportunistic pathogen for rainbow trout oncorhynchus mykiss walbaum in china
    Veterinary Microbiology, 2009
    Co-Authors: Jin Yu Liu, Wu Ming Yang
    Abstract:

    Six strains of Gram-positive, catalase-negative, non-motile, irregular short rod-shaped Weissella bacteria, with width and length of 0.5-0.6 and 1.2-2.7 mu m were isolated from diseased rainbow trout Oncorhynchus mykiss (Walbaum) in winter of 2007 at a commercial fishery in Jingmen, Hubei province, China. The diseased rainbow trout exhibited hemorrhage in eyes, anal region, intestine and abdomen wall, petechia of liver, some fish with hydrocele in stomach. Six isolates had identical biochemical reactions, phylogenetic analysis of 16S rDNA sequences, amplified ribosomal DNA restriction analysis (ARDRA), enzymatic profile analysis and antimicrobial susceptibility results, indicating as a single clonal outbreak. But all were different from any other validated twelve Weissella species in the term of physiological and biochemical characters. It is indicated that isolates are phylogenetically closer to Weissella halotolerans, Weissella viridescens and Weissella minor on 16S rDNA phylogenetic analysis result, than to W halotolerans and W viridescens on the result of ARDRA study and enzymatic profile analysis. Antimicrobial susceptibility testing was used to scan effective drugs for the therapy of this disease. Experimental infection assays with one isolate were conducted and pathogenicity (by intraperitoneal injection) was demonstrated in rainbow trout O. mykiss (Walbaum) and crucian carp (Carassius auratus gibelio) fingerlings. Because no Weissella was detected in fish feedstuffs and pond water, the source of this pathogen remains unknown, and Weissella isolates were regarded as an opportunistic pathogen for rainbow trout. This is the first report of Weissella strains which can cause disease of cultured fish in the world. (C) 2009 Elsevier B.V. All rights reserved.

  • First description of a novel Weissella species as an opportunistic pathogen for rainbow trout Oncorhynchus mykiss (Walbaum) in China.
    Veterinary microbiology, 2008
    Co-Authors: Jin Yu Liu, Wu Ming Yang
    Abstract:

    Six strains of Gram-positive, catalase-negative, non-motile, irregular short rod-shaped Weissella bacteria, with width and length of 0.5-0.6 and 1.2-2.7microm were isolated from diseased rainbow trout Oncorhynchus mykiss (Walbaum) in winter of 2007 at a commercial fishery in Jingmen, Hubei province, China. The diseased rainbow trout exhibited hemorrhage in eyes, anal region, intestine and abdomen wall, petechia of liver, some fish with hydrocele in stomach. Six isolates had identical biochemical reactions, phylogenetic analysis of 16S rDNA sequences, amplified ribosomal DNA restriction analysis (ARDRA), enzymatic profile analysis and antimicrobial susceptibility results, indicating as a single clonal outbreak. But all were different from any other validated twelve Weissella species in the term of physiological and biochemical characters. It is indicated that isolates are phylogenetically closer to Weissella halotolerans, Weissella viridescens and Weissella minor on 16S rDNA phylogenetic analysis result, than to W. halotolerans and W. viridescens on the result of ARDRA study and enzymatic profile analysis. Antimicrobial susceptibility testing was used to scan effective drugs for the therapy of this disease. Experimental infection assays with one isolate were conducted and pathogenicity (by intraperitoneal injection) was demonstrated in rainbow trout O. mykiss (Walbaum) and crucian carp (Carassius auratus gibelio) fingerlings. Because no Weissella was detected in fish feedstuffs and pond water, the source of this pathogen remains unknown, and Weissella isolates were regarded as an opportunistic pathogen for rainbow trout. This is the first report of Weissella strains which can cause disease of cultured fish in the world.