| 益田 時光（ますだ よしみつ） | データ更新日：2023.11.27 |
助教 ／
農学研究院
生命機能科学部門
食料科学工学講座
| 1. | Phan Nguyen Trang, Tong Thi Anh Ngoc, Yoshimitsu Masuda, Ken-ichi Hohjoh, Takahisa Miyamoto,, Biofilm Formation From Listeria monocytogenes Isolated From Pangasius Fish-processing Plants, Journal of Food Protection, https://doi.org/10.1016/j.jfp.2023.100044, 86, 3, 100044, 100044, 2023.03. |
| 2. | Yuan L, Nakamichi R, Hirata Y, Matsuda A, Shinohara Y, Yamada A, Masuda Y, Honjoh KI, Miyamoto T., Mechanism for inhibition of cytotoxicity of Shiga toxin by luteolin, Toxicol In Vitro, 10.1016/j.tiv.2022.105537, 87, 105537, 105537, 2023.01. |
| 3. | Hoang Minh Duc, Yu Zhang, Hoang Minh Son, Hung-Hsin Huang, Yoshimitsu Masuda, Ken-ichi Honjoh, Takahisa Miyamoto, Genomic characterization and application of a novel bacteriophage STG2 capable of reducing planktonic and biofilm cells of Salmonella, International Journal of Food Microbiology, https://doi.org/10.1016/j.ijfoodmicro.2022.109999, 2023.01. |
| 4. | Trang Nguyen Phan, Anh Ngoc Tong Thi, Yoshimitsu Masuda, Ken-ichi Hohjoh, Takahisa Miyamoto, Slightly acidic hypochlorous water effective against dual-species biofilm of Listeria monocytogenes and Escherichia coli strains isolated from Pangasius fish-processing plants, Food Science and Technology Research, https://doi.org/10.3136/fstr.FSTR-D-22-00074, 28, 6, 521-527, 2022.09, This study illustrates the effectiveness of slightly acidic hypochlorous water (SAHW) in comparison with sodium hypochlorite (NaOCl) in reducing biomass and viable cells in biofilms established by the dual species, Listeria monocytogenes and Escherichia coli, on a microtiter plate and stainless-steel coupon. The SAHW and NaOCl treatments exhibited significant efficacy against biofilms (p |
| 5. | Tahir Noor Mohammadi, Cunkuan Shen, Yuncheng Li, Mahmoud Gamaleldin Zayda, Jun Sato, Yoshimitsu Masuda, Ken-ichi Honjoh, Takahisa Miyamoto, Characterization and optimization of bacteriophage cocktails to control Clostridium perfringens in vitro and in curry roux, International Journal of Food Microbiology, https://doi.org/10.1016/j.ijfoodmicro.2022.109886, 380, 109886, 2022.08, Clostridium perfringens is a major cause of foodborne disease in developed countries. The aim of this study was to isolate and characterize phages specific to C. perfringens to evaluate the most efficient phage cocktail for the biocontrol of C. perfringens, both in vitro and in curry roux. In this study, four phages were isolated from chicken meat and were morphologically and genetically characterized along with two phages previously isolated in our laboratory that display different host lysis spectra. Phage cocktail CP11, consisting of phages CPQ3, 7, 8, and 10, showed the broadest host range. Electron micrograph images suggested that all four phages belong to the Podoviridae family, and none of them carry any antibiotic resistance or toxin genes. Notably, the phages were stable at various pH values and in curry roux. Cocktails consisting of six, five, and four phages at the same concentrations were examined to determine the most effective phage cocktail. Phage cocktail PC11 significantly decreased the viable count of C. perfringens to a value less than the lower detection limit up to 48 h at both 8 and 37 °C in broth and at 24 °C in the curry roux. These results suggest that phage cocktail PC11 is a promising natural biocontrol agent against C. perfringens in vitro and in curry roux.. |
| 6. | Zhang, Y., Huang, H.-H., Ma, L.Z., Masuda, Y., Honjoh, K.-I., Miyamoto, T., Inactivation of mixed Escherichia coli O157:H7 biofilms on lettuce by bacteriophage in combination with slightly acidic hypochlorous water (SAHW) and mild heat treatment, Food Microbiology, https://doi.org/10.1016/j.fm.2022.104010, 104, 104010, 2022.06. |
| 7. | Cunkuan Shen, Yunzhi Lin, Tahir Noor Mohammadi, Yoshimitsu Masuda, Ken-ichi Honjoh, Takahisa Miyamoto, Characterization of novel antimicrobial peptides designed on the basis of amino acid sequence of peptides from egg white hydrolysate, International Journal of Food Microbiology, https://doi.org/10.1016/j.ijfoodmicro.2022.109802, 378, 109802, 2022.06, Salmonella enterica subsp. enterica serotype Typhimurium (S. Typhimurium) is one of the most prevalent foodborne pathogens responsible for food poisoning and is spread through the consumption of contaminated poultry products. In this study, four antimicrobial peptides (AMPs) with varying hydrophobicity and helical structureforming tendencies were designed and synthesized based on the amino acid sequences of peptides from egg white hydrolysate. Two of these AMPs, P1R3 (KSWKKHVVSGFFLR) and P1C (KSWKKHVVSGFFLRLWVHKK), exhibited inhibitory activity against S. Typhimurium and compromised its biofilm-forming ability. Investigation of their modes of action revealed that P1R3 and P1C interact with and permeabilize the cytoplasmic membrane of bacteria, leading to membrane potential dissipation, damage to membrane integrity, and consequent bacterial death. P1R3 also bound to S. Typhimurium DNA, resulting in DNA aggregation or precipitation. Moreover, both peptides showed negligible cytotoxicity to Vero cells, and P1C displayed significant antimicrobial activity in chicken meat. Peptides P1R3 and P1C, therefore, have the potential to be developed as promising food preservatives, especially against pathogenic S. Typhimurium.. |
| 8. | Yu Zhang, Hung-Hsin Huang, Hoang Minh Duc, Yoshimitsu Masuda, Ken-ichi Honjoh, Takahisa Miyamoto, Application of endolysin LysSTG2 as a potential biocontrol agent against planktonic and biofilm cells of Pseudomonas on various food and food contact surfaces, Food Control, https://doi.org/10.1016/j.foodcont.2021.108460, 131, 108460, 2022.01, [URL].  |
| 9. | Tahir Noor Mohammadi, Cunkuan Shen, Yuncheng Li, Mahmoud Gamaleldin Zayda, Jun Sato, Yoshimitsu Masuda, Ken-ichi Honjoh, Takahisa Miyamoto, Characterization of Clostridium perfringens bacteriophages and their application in chicken meat and milk, INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY, 10.1016/j.ijfoodmicro.2021.109446, 361, 2022.01, [URL]. |
| 10. | Trang Nguyen Phan, Takahisa Miyamoto, Yoshimitsu Masuda, Ken-ichi Hohjoh, Anh Ngoc Tong Thi, Occurrence, antimicrobial resistance, and genetic diversity of Listeria monocytogenes at fish-processing plants in Vietnam, Food Science and Technology Research, DOI: 10.3136/fstr.FSTR-D-21-00195, 28, 2, 141-149, 2022.01, In this study, the occurrence, serogroups, virulence genes, antibiotic susceptibility profiles, and diversity were estimated for Listeria monocytogenes isolated from Pangasius fish in two processing facilities in Vietnam. L. monocytogenes was most frequently detected in wash water samples at 20.8 % (15 out of 72), and in Pangasius fish it was 16.6 % (15 out of 90 fish samples). Serotypes 1/2b were dominant, and internalin genes (inlA, inlC, and inlJ) were found in all the L. monocytogenes isolates. Most of the isolates were resistant to cefoxitin, oxacillin, and fosfomycin. Genotyping of L. monocytogenes by random amplified polymorphic DNA analysis revealed three clusters of the isolates specific to the facilities to some extent. This study suggests a high risk of L. monocytogenes contamination from wash water to fish. Hence, maintaining the quality of water and designing sanitation procedures to reduce L. monocytogenes contamination are required to ensure food safety at Pangasius fish processing plants.. |
| 11. | Khin Zar Linn, Munenori Furuta, Motokazu Nakayama, Yoshimitsu Masuda, Ken-ichi Honjoh, Takahisa Miyamoto, Characterization and antimicrobial resistance of Campylobacter jejuni and Campylobacter coli isolated from chicken and pork, International Journal of Food Microbiology, DOI: 10.1016/j.ijfoodmicro.2021.109440, 360, 109440, 2021.10, The prevalence and antimicrobial resistance (AMR) profile were investigated in Campylobacter jejuni and Campylobacter coli in chicken and pork in Fukuoka, Japan in 2019. Their AMR profiles were compared with those of C. jejuni and C. coli strains isolated in 2013. A total of 53 chicken and 14 pork samples were collected from different supermarkets in Fukuoka in 2019. Campylobacter spp. were isolated by conventional method and characterized by PCR and MALDI-TOF MS. Among 53 chicken samples tested in 2019, 24.5% and 5.7% were positive for C. jejuni and C. coli, respectively, and three (21.4%) of 14 pork samples were positive for C. coli, but not C. jejuni. From the positive samples, 13 and six strains of C. jejuni and C. coli were isolated, respectively. Antimicrobial susceptibility test against 12 different antimicrobials were performed on 48 isolates (43 C. jejuni and five C. coli) from chicken in 2013 and 19 isolates (13 C. jejuni from chicken, three C. coli from chicken and three C. coli from pork) in 2019 using the disk diffusion method. All the C. jejuni and C. coli isolated in 2013 and 2019 were highly resistant to cefazolin and sulfamethoxazole/trimethoprim. Among the C. jejuni isolates from chickens, 25.6% of 2013 isolates were resistant to nalidixic acid, ciprofloxacin, and levofloxacin, and 7% to ampicillin and minocycline, while 30.8% of the isolates were resistant to minocycline, 23.1% to nalidixic acid, ciprofloxacin, and levofloxacin, and 15.4% to ampicillin in 2019. Among the C. coli isolates, 80% of isolates from chickens in 2013, and 33.3% from chicken and 100% from pork in 2019 were resistant to nalidixic acid, ciprofloxacin, and levofloxacin. The frequency of multi-drug resistant (MDR) C. jejuni and C. coli strains from chickens in 2019 were 30.8% and 33.3%, respectively, which were lower than those isolated in 2013 (37.2% and 100%, respectively). One C. jejuni and two C. coli isolates from 2013 were resistant to six antibiotics. However, two C. jejuni and one C. coli isolate from chickens in 2019 were resistant to seven and five antibiotics, respectively. All the C. coli isolates from pork in 2019 were resistant to five antibiotics. The high frequency of AMR strains in C. coli isolates from pork suggests that appropriate use of antimicrobials is required in swine husbandry.. |
| 12. | Yu Zhang, Hung-Hsin Huang, Hoang Minh Duc, Yoshimitsu Masuda, Ken-ichi Honjoh, Takahisa Miyamoto, Endolysin LysSTG2: Characterization and application to control Salmonella Typhimurium biofilm alone and in combination with slightly acidic hypochlorous water, Food Microbiology, 10.1016/j.fm.2021.103791, 98, 103791, 2021.09. |
| 13. | Yoshimitsu Masuda, Shun Kawabata, Tatsuya Uedoi, Ken-ichi Honjoh, Takahisa Miyamoto, Construction of Leaderless-Bacteriocin-Producing Bacteriophage Targeting E. coli and Neighboring Gram-Positive Pathogens, Microbiology Spectrum, 10.1128/Spectrum.00141-21, 9, 1, e00141-21, 2021.09, [URL]. |
| 14. | Yu Zhang, Hung-Hsin Huang, Hoang Minh Duc, Yoshimitsu Masuda, Ken-ichi Honjoh, Takahisa Miyamoto, Endolysin LysSTG2: Characterization and application to control Salmonella Typhimurium biofilm alone and in combination with slightly acidic hypochlorous water, Food Microbiology, 10.1016/j.fm.2021.103791, 98, 103791, 2021.09. |
| 15. | Hung-Hsin Huang, Munenori Furuta, Takayuki Nasu, Miku Hirono, Jaroenkolkit Pruet, Hoang Minh Duc, Yu Zhang, Yoshimitsu Masuda, Ken-ichi Honjoh, Takahisa Miyamoto, Inhibition of phage-resistant bacterial pathogen re-growth with the combined use of bacteriophages and EDTA, Food Microbiology, 10.1016/j.fm.2021.103853, 100, 103853, 2021.06, [URL]. |
| 16. | Cunkuan Shen, Chikako Machida, Yoshimitsu Masuda, Ken-ichi Honjoh, Takahisa Miyamoto, Effect of Selected Food Additives on Biofilm Formation by Foodborne Pathogens on Stainless Steel, 九州大学大学院農学研究院紀要, 10.5109/4363550, 66, 1, 45-52, 2021.04. |
| 17. | Yu Zhang, Kumiko Shigemura, Hoang Minh Duc, Cunkuan Shen, Hung-Hsin Huang, Jun Sato, Yoshimitsu Masuda, Ken-ichi Honjoh, Takahisa Miyamoto, Effects of bacteriophage on inhibition and removal of mixed biofilm of enterohemorrhagic Escherichia coli O157:H7 and O91:H-, LWT - Food Science and Technology, 10.1016/j.lwt.2020.109945, 134, 109945, 2020.12. |
| 18. | Apisada Kitichalermkiat, Mao Katsuki, Jun Sato, Takumi Sonoda, Yoshimitsu Masuda, Ken-ichi Honjoh, Takahisa Miyamoto, Effect of epigallocatechin gallate on gene expression of Staphylococcus aureus, Journal of Global Antimicrobial Resistance , 10.1016/j.jgar.2020.06.006, 22, 854-859, 2020.09. |
| 19. | Yoshimitsu Masuda, Erika Sakamoto, Ken-ichi Honjoh, Takahisa Miyamoto, Role of Toxin-Antitoxin-Regulated Persister Population and Indole in Bacterial Heat Tolerance, Applied and Environmental Microbiology, 10.1128/AEM.00935-20, 86, 16, e00935-20, 2020.08. |
| 20. | Hoang Minh Duc, Hoang Minh Son, Hazel Pang Shu Yi, Jun Sato, Pham Hong Ngan, Yoshimitsu Masuda, Ken ichi Honjoh, Takahisa Miyamoto, Isolation, characterization and application of a polyvalent phage capable of controlling Salmonella and Escherichia coli O157:H7 in different food matrices, Food Research International, 10.1016/j.foodres.2020.108977, 131, 2020.05, [URL], Salmonella Enteritidis, Salmonella Typhimurium, and Escherichia coli O157:H7 are the most important foodborne pathogens, causing serious food poisoning outbreaks worldwide. Bacteriophages are increasingly considered as novel antibacterial agents to control foodborne pathogens. In this study, 8 Salmonella phages and 10 E. coli O157:H7 phages were isolated from chicken products. A polyvalent phage PS5 capable of infecting S. Enteritidis, S. Typhimurium, and E. coli O157:H7 was further characterized and its efficacy in reducing these foodborne pathogens was evaluated in in vitro and in foods. Morphology, one-step growth, and stability assay showed that phage PS5 was a myovirus, with relatively short latent periods, large burst sizes, and high stability. Genome sequencing analysis revealed that the genome of PS5 does not contain any genes associated to antibiotic resistance, toxins, lysogeny, and virulence factors. In broth, phage PS5 significantly decreased the viable counts of all the three bacterial hosts by more than 1.3 log CFU/mL compared to controls after 2 h of incubation at 4 °C and 24 °C. In foods, treatment with PS5 also resulted in significant reductions of viable counts of all the three bacterial hosts compared to controls at temperatures tested. This is the first report on single phage capable of simultaneously controlling S. Enteritidis, S. Typhimurium and E. coli O157:H7 in both in vitro and in foods.. |
| 21. | Mahmoud Ge Zayda, Yoshimitsu Masuda, Ahmed M. Hammad, Ken ichi Honjoh, Abdelrahman M. Elbagory, Takahisa Miyamoto, Molecular characterisation of methicillin-resistant (MRSA) and methicillin-susceptible (MSSA) Staphylococcus aureus isolated from bovine subclinical mastitis and Egyptian raw milk cheese, International Dairy Journal, 10.1016/j.idairyj.2020.104646, 104, 2020.05, [URL], We investigated the characteristics of Staphylococcus aureus isolates causing bovine subclinical mastitis (SCM), and their genetic relatedness with the isolates obtained from Egyptian cheese. Twenty-five S. aureus isolates were identified from 150 SCM milk and 75 cheese samples. The antibiogram revealed multidrug-resistant (MDR) isolates. Fifteen isolates were categorised as methicillin-resistant. Antimicrobial resistance and virulence genes were detected. Spa typing and SCCmec classification were performed. More than 50% of isolates were found carrying human-specific virulence determinants, while other isolates characterised were presumed to be of bovine-origin. Spa-types t304, t688, t084 corresponded isolates from SCM milk and cheese samples; the similar genotypes from SCM and cheese displayed divergence in virulence traits. Moreover, our results revealed the novel spa-type t18546. Animals and dairy food could be a reservoir for transformative changes in S. aureus virulence, leading to the emergence of virulent MDR strains that may become potential public-health threats.. |
| 22. | Cunkuan Shen, Md Tariqul Islam, Yoshimitsu Masuda, Ken ichi Honjoh, Takahisa Miyamoto, Transcriptional changes involved in inhibition of biofilm formation by ε-polylysine in Salmonella Typhimurium, Applied Microbiology and Biotechnology, 10.1007/s00253-020-10575-2, 2020.01, [URL], The pathogenicity of Salmonella Typhimurium, a foodborne pathogen, is mainly attributed to its ability to form biofilm on food contact surfaces. ε-polylysine, a polymer of positively charged lysine, is reported to inhibit biofilm formation of both gram-positive and gram-negative bacteria. To elucidate the mechanism underlying ε-polylysine-mediated inhibition of biofilm formation, the transcriptional profiles of ε-polylysine-treated and untreated Salmonella Typhimurium cells were comparatively analysed. The genome-wide DNA microarray analysis was performed using Salmonella Typhimurium incubated with 0.001% ε-polylysine in 0.1% Bacto Soytone at 30 °C for 2 h. The expression levels of genes involved in curli amyloid fibres and cellulose production, quorum sensing, and flagellar motility were downregulated, whereas those of genes associated with colanic acid synthesis were upregulated after treatment with ε-polylysine. The microarray results were validated by quantitative real-time polymerase chain reaction (qRT-PCR). Furthermore, treatment with ε-polylysine decreased the production of colanic acid in Salmonella Typhimurium. The findings of this study improved our understanding of the mechanisms underlying ε-polylysine-mediated biofilm inhibition and may contribute to the development of new disinfectants to control biofilm during food manufacturing and storage.. |
| 23. | Guo Yue, Cui, Xiaowen Ou Liushu, Isowaki Chika, 九大 Masuda Yoshimitsu, 九大 Honjoh Ken-ichi, 九大 Miyamoto Takahisa , Effects of Sucrose on Heat Resistance and Gene Expression in Salmonella Typhimurium, FOOD SCIENCE AND TECHNOLOGY RESEARCH, 10.3136/fstr.25.903, 25, 6, 903-913, 2019.11. |
| 24. | Aye Thida Maung, Tahir Noor Mohammadi, Satoko Nakashima, Pei Liu, Yoshimitsu Masuda, Ken-Ichi Honjoh, Takahisa Miyamoto, Antimicrobial resistance profiles of Listeria monocytogenes isolated from chicken meat in Fukuoka, Japan, International Journal of Food Microbiology, 10.1016/j.ijfoodmicro.2019.05.016, 304, 49-57, 2019.09, [URL], In this study, the antimicrobial resistance profiles of L. monocytogenes isolated from chicken meat in Fukuoka in 2017 were compared with the isolates of 2012. A total of 85 and 50 chicken meat samples, including different body parts, were collected from different supermarkets in Fukuoka in 2012 and 2017, respectively. Detection, isolation, identification, and characterization of L. monocytogenes were performed according to the conventional methods. Forty-five among 85 samples (53%) were positive for L. monocytogenes in 2012, while 12 among 50 samples in 2017 (24%) tested positive. One hundred fifty-three and 29 L. monocytogenes strains were isolated in 2012 and 2017, respectively. The serotypes of isolates in 2012 were 1/2a (21.5%), 1/2b (73.9%), 1/2c (1.5%), and 4b/4e (3.1%). In contrast, the 2017 isolates showed 1/2a (48.3%) and 1/2b (51.7%) serotypes. While all isolates in 2012 were positive for hlyA (listeriolysin O) in the PCR assay with hlyA primer set 7, only 17 hlyA positive isolates were seen in 2017. Moreover, 75 isolates with different ribotypes in 2012 and 29 isolates in 2017, respectively, were tested for antimicrobial susceptibility by broth microdilution for 18 different antimicrobial agents. Most of the 2012 and 2017 isolates displayed antimicrobial susceptibility. However, among the 2012 and 2017 isolates, 98.7% and 100% of the isolates were resistant to cefoxitin, 57.3% and 95.7% to fosfomycin, 72.0% and 82.6% to oxacillin, 8.0% and 17.4% to clindamycin, respectively. In addition, 2.7% of the isolates in 2012 were resistant to flomoxef and 4.3% of the isolates in 2017 to linezolid. Multidrug resistance (MDR) to 3 or more antimicrobials was observed in 35/75 (46.7%) isolates of 2012 and 19/23 (82.6%) in 2017. Detection of antimicrobial resistance (AMR) genes by PCR showed that the resistant isolates of 2012 were positive for mecA (96.3%) and ermC (83.3%), whereas the resistant isolates in 2017 screened positive for mecA (94.7%) and mefA (25.0%). Other cfxA, ermA, ermB, fosA, fosB, and fosC genes were absent in the PCR assay for any of the isolates. This study investigated for the first time the change in the L. monocytogenes contamination of chicken meat and antibiotic resistance of the isolated L. monocytogenes strains in Fukuoka, Japan, in the course of 5 years. Although the contamination rate of L. monocytogenes in 2017 was found to be lower than that in 2012, AMR of the isolates in 2017 was higher.. |
| 25. | Pham Thi Vinh, Yui Shinohara, Akifumi Yamada, Hoang Minh Duc, Motokazu Nakayama, Tadahiro Ozawa, Jun Sato, Yoshimitsu Masuda, Ken Ichi Honjoh, Takahisa Miyamoto, Baicalein inhibits Stx1 and 2 of EHEC Effects of baicalein on the cytotoxicity, production, and secretion of shiga toxins of enterohaemorrhagic escherichia coli, Toxins, 10.3390/toxins11090505, 11, 9, 2019.08, [URL], Shiga toxin-producing enterohaemorrhagic Escherichia coli (EHEC) O157:H7 is an important foodborne pathogen. Baicalein (5,6,7-trihydroxylflavone), a flavone isolated fromthe roots of Scutellaria baicalensis, is considered as a potential antibacterial agent to control foodborne pathogens. Among seven compounds selected by in silico screening of the natural compound database, baicalein inhibited the cytotoxicity of both Shiga toxins 1 and 2 (Stx1 and Stx2) against Vero cells after pretreatment at 0.13 mmol/L. In addition, baicalein reduced the susceptibility of Vero cells to both Stx1 and Stx2. Real-time qPCR showed that baicalein increased transcription of stx1 but not of stx2. However, baicalein had no effects on production or secretion of Stx1 or Stx2. Docking models suggested that baicalein formed a stable structure with StxB pentamer with low intramolecular energy. The results demonstrate that inhibitory activity of baicalein against the cytotoxicity of both Stx1 and Stx2 might be due to of the formation of a binding structure inside the pocket of the Stx1B and Stx2B pentamers.. |
| 26. | Xiaowen Cui, Chuanqi Hu, Liushu Ou, Yumiko Kuramitsu, Yoshimitsu Masuda, Ken-Ichi Honjoh, Takahisa Miyamoto, Transcriptional analysis on heat resistance and recovery from thermal damage in Salmonella under high salt condition, LWT, 10.1016/j.lwt.2019.02.056, 106, 194-200, 2019.06, [URL], Sodium chloride maintains osmotic pressure of living cells including bacteria. Heat treatment is common for decontamination of bacteria in food. In this study, effects of NaCl on heat resistance of Salmonella Typhimurium were investigated. After cultivation in TSB containing 0.5% (TSB), 4% (4SC) and 8% (8SC) NaCl, S. Typhimurium cells were heated at 60 °C for 20 min. Total viable counts including intact cells and injured but recoverable cells determined by the plating method using TSA of S. Typhimurium cultured in 4SC and 8SC were significantly higher than those of the cells cultured in TSB. Meanwhile, changes of gene transcription were analyzed by DNA microarray. Transcription of genes involved in the colanic acid synthesis largely increased after cultivation in 4SC and 8SC. The amount of colanic acid significantly increased in the cells cultured in 4SC compared to that in M9-glucose medium. After recovery culture for 3 h, the genes involved in the phage shock response strongly up-regulated, suggesting contribution of these gene products in recovery of heat injured cells. The outcome of this study contributes to understand the mechanism of cross protection in Salmonella.. |
| 27. | T. Noor Mohammadi, A. T. Maung, J. Sato, T. Sonoda, Yoshimitsu Masuda, Ken-Ichi Honjoh, Takahisa Miyamoto, Mechanism for antibacterial action of epigallocatechin gallate and theaflavin-3,3′-digallate on Clostridium perfringens, Journal of Applied Microbiology, 10.1111/jam.14134, 126, 2, 633-640, 2019.02, [URL], Aim: The purpose of this study was to clarify the mechanism of the antibacterial action of two high potential and natural food additives, epigallocatechin gallate (EGCg) and theaflavin-3,3′-digallate (TF3), on Clostridium perfringens. Methods and Results: Minimal inhibitory concentrations were determined by the serial dilution method. Afterwards, the cells were treated with 250 or 1000 mg l −1 of EGCg and 125 or 500 mg l −1 of TF3 and morphological changes were observed and cell sizes were also measured under fluorescence microscopy. Our results showed that TF3 had a twice stronger antibacterial activity than EGCg against C. perfringens. Phase-contrast and fluorescence microscopy confirmed that the bacterial cells elongated without DNA segregation and septum formation in the presence of 250 mg l −1 EGCg. While in the higher concentration of EGCg and TF3, cell growth was suppressed. Bacterial cells reached to around 12 μm after the 24 h incubation with 250 mg l −1 EGCg, but the cells were shorter than the control at 1000 mg l −1 of EGCg. After washing and incubating the elongated cells in fresh medium, DNA segregated at 2 h of incubation. The average cell length decreased gradually and reached the normal size at 8 h. Conclusion: It seems that EGCg at a low concentration affected the proteins involved in the septum formation, DNA segregation and cell division. Furthermore, the high concentration of EGCg and TF3 seemed to cause stronger cellular damage to C. perfringens. Significance and Impact of the Study: These polyphenols are widely distributed in all higher plants especially in tea plants, and people tend to use natural food additives rather than synthetic ones. EGCg and TF3, as natural food additives, can prevent C. perfringens food poisoning along with other potential health benefits.. |
| 28. | Apisada Kitichalermkiat, Masahiro Kurahachi, Ai Nonaka, Motokazu Nakayama, Kanami Shimatani, Naofumi Shigemune, Takashi Tsugukuni, Jun Hitomi, Jun Sato, Takumi Sonoda, Yoshimitsu Masuda, Ken-Ichi Honjoh, Takahisa Miyamoto, Effects of Epigallocatechin Gallate on Viability and Cellular Proteins of Staphylococcus aureus, Food Science and Technology Research, 10.3136/fstr.25.277, 25, 2, 277-285, 2019.01, [URL], This study investigated the effect of epigallocatechin gallate (EGCg) on Staphylococcus aureus to determine its mechanism of antibacterial action. Adsorption of EGCg on the cell envelope of S. aureus after EGCg treatment was demonstrated using a FITC-labeled antibody specific to EGCg. After EGCg treatment of S. aureus for 4 h, abnormalities in septum formation and cell segregation were observed at concentrations greater than 250 mg/L, and debris presumed to arise from cell destruction or leakage of cytoplasmic materials was observed around the cells at 500 mg/L. Two-dimensional electrophoresis of proteins prepared from EGCg-treated S. aureus cells revealed the presence of 18 protein spots that disappeared or showed markedly decreased intensity compared to those from control cells. These proteins included DnaK, elongation factor G, DNA-directed RNA polymerase, l-lactate dehydrogenase, pyruvate dehydrogenase, and acetate kinase. Furthermore, S. aureus showed decreased glucose uptake after EGCg treatment. These results suggest that EGCg inhibits the functions of cell-envelope proteins, and it causes cellular damage and disruption of the cells in S. aureus.. |
| 29. | Hoang Minh Son, Hoang Minh Duc, Yoshimitsu Masuda, Ken-Ichi Honjoh, Takahisa Miyamoto, Application of bacteriophages in simultaneously controlling Escherichia coli O157:H7 and extended-spectrum beta-lactamase producing Escherichia coli, Applied Microbiology and Biotechnology, 10.1007/s00253-018-9399-1, 102, 23, 10259-10271, 2018.12, [URL], Shiga toxin-producing Escherichia coli (STEC) O157:H7 and extended-spectrum beta-lactamase (ESBL) producing E. coli (ESBLEC) are important bacteria of public health concern and frequently isolated from raw beef products. Bacteriophage-based methods have been increasingly exploited to control bacterial contamination in meats. Here, we describe the isolation, characterization, and application of a lytic phage PE37 for the simultaneous bio-control of STEC O157:H7 and ESBLEC. Phage PE37, isolated from the bovine intestine, was morphologically characterized as a member of the Myoviridae family, with a broad host range and great stability under various stress conditions. Sequencing analysis revealed that the genomic DNA of phage PE37 contains genes that contribute to virion structure, replication, assembly, and host lysis. PE37 significantly reduced the viable counts of STEC O157:H7 by 4.9 and 2.6 log CFU/mL in broth after 6 h of incubation at 25 and 8 °C, respectively. Application of phage PE37 to raw beef artificially contaminated with STEC O157:H7 resulted in significant reductions in the viable counts by 2.3 and 0.9 log CFU/piece after 24 h of storage at 25 and 8 °C, respectively. Treatment of raw beef contaminated with a bacterial cocktail of STEC O157:H7 and ESBLEC with PE37 also significantly decreased the viable counts of the bacterial mixture by 1.4 and 1.0 log CFU/piece after 24 h of incubation at 25 and 8 °C, respectively. These findings suggest that bacteriophage PE37 may be a potential bio-agent for controlling STEC O157:H7 and ESBLEC contamination in raw beef.. |
| 30. | Xiaowen Cui, Hsu Ming Sherman Wen, Yoshimasa Kinoshita, Shota Koishi, Chika Isowaki, Liushu Ou, Yoshimitsu Masuda, Ken-Ichi Honjoh, Takahisa Miyamoto, Role of phage shock protein in recovery of heat-injured salmonella, Biocontrol Science, 10.4265/bio.23.17, 23, 1, 17-25, 2018.01, [URL], Sublethally heat-injured cells of Salmonella in food can recover under favorable conditions, leading to foodborne illness. To elucidate the molecular mechanism of recovery from heat injury, the global changes in gene transcription of Salmonella Typhimurium were investigated in previous study. In this study, the functions of genes involved in phage shock response（viz., phage shock protein（psp）genes）, the transcription levels of which were found in previous study to be increased during recovery from heat injury, were investigated in recovering cells. The increase in pspABCDEFG transcription levels during the recovery process was confirmed by qRT-PCR. To understand the role of psp genes in heat injury recovery, a pspA deletion mutant（ΔpspA）and a pspA-overexpressing strain（S. Typhimurium pBAD30/pspA（+））were constructed. ΔpspA showed slightly lower viable counts and membrane potential than those of the wild-type strain during recovery. On the other hand, there was no significant difference in the viable counts between S. Typhimurium pBAD30/pspA（+）and the control strains S. Typhimurium pBAD30/pspA （-）and S. Typhimurium pBAD30（+）during recovery. It would seem that a lack of PspA protein alone somewhat affects the recovery of S. Typhimurium from heat injury, but overexpression of PspA alone is not sufficient to overcome this effect.. |
| 31. | Yoshimitsu Masuda, R. H. Perez, Takeshi Zendo, Kenji Sonomoto, Nutrition-adaptive control of multiple-bacteriocin production by Weissella hellenica QU 13, Journal of Applied Microbiology, 10.1111/jam.12997, 120, 1, 70-79, 2016.01, [URL], 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.. |
| 32. | Rodney H. Perez, Naoki Ishibashi, Tomoko Inoue, Kohei Himeno, Yoshimitsu Masuda, Narukiko Sawa, Takeshi Zendo, Pongtep Wilaipun, Vichien Leelawatcharamas, Jiro Nakayama, Kenji Sonomoto, Functional analysis of genes involved in the biosynthesis of enterocin NKR-5-3B, a novel circular bacteriocin, Journal of Bacteriology, 10.1128/JB.00692-15, 198, 2, 291-300, 2015.12, [URL], A putative biosynthetic gene cluster of the enterocin NKR-5-3B (Ent53B), a novel circular bacteriocin, was analyzed by sequencing the flanking regions around enkB, the Ent53B structural gene, using a fosmid library. A region approximately 9 kb in length was obtained, and the enkB1, enkB2, enkB3, and enkB4 genes, encoding putative biosynthetic proteins involved in the production, maturation, and secretion of Ent53B, were identified. We also determined the identity of proteins mediating self-immunity against the effects of Ent53B. Heterologous expression systems in various heterologous hosts, such as Enterococcus faecalis and Lactococcus lactis strains, were successfully established. The production and secretion of the mature Ent53B required the cooperative functions of five genes. Ent53B was produced only by those heterologous hosts that expressed protein products of the enkB, enkB1, enkB2, enkB3, and enkB4 genes. Moreover, self-immunity against the antimicrobial action of Ent53B was conferred by at least two independent mechanisms. Heterologous hosts harboring the intact enkB4 gene and/or a combination of intact enkB1 and enkB3 genes were immune to the inhibitory action of Ent53B.. |
| 33. | Naoki Ishibashi, Kohei Himeno, Yoshimitsu Masuda, Rodney Honrada Perez, Shun Iwatani, Takeshi Zendo, Pongtep Wilaipun, Vichien Leelawatcharamas, Jiro Nakayama, Kenji Sonomoto, Gene cluster responsible for secretion of and immunity to multiple bacteriocins, the NKR-5-3 enterocins, Applied and Environmental Microbiology, 10.1128/AEM.02312-14, 80, 21, 6647-6655, 2014.11, [URL], Enterococcus faecium NKR-5-3, isolated from Thai fermented fish, is characterized by the unique ability to produce five bacteriocins, namely, enterocins NKR-5-3A, -B, -C, -D, and -Z (Ent53A, Ent53B, Ent53C, Ent53D, and Ent53Z). Genetic analysis with a genome library revealed that the bacteriocin structural genes (enkA [ent53A], enkC [ent53C], enkD [ent53D], and enkZ [ent53Z]) that encode these peptides (except for Ent53B) are located in close proximity to each other. This NKR-5-3ACDZ (Ent53ACDZ) enterocin gene cluster (approximately 13 kb long) includes certain bacteriocin biosynthetic genes such as an ABC transporter gene (enkT), two immunity genes (enkIaz and enkIc), a response regulator (enkR), and a histidine protein kinase (enkK). Heterologous- expression studies of enkT and ΔenkT mutant strains showed that enkT is responsible for the secretion of Ent53A, Ent53C, Ent53D, and Ent53Z, suggesting that EnkT is a wide-range ABC transporter that contributes to the effective production of these bacteriocins. In addition, EnkIaz and EnkIc were found to confer self-immunity to the respective bacteriocins. Furthermore, bacteriocin induction assays performed with the ΔenkRK mutant strain showed that EnkR and EnkK are regulatory proteins responsible for bacteriocin production and that, together with Ent53D, they constitute a three-component regulatory system. Thus, the Ent53ACDZ gene cluster is essential for the biosynthesis and regulation of NKR-5-3 enterocins, and this is, to our knowledge, the first report that demonstrates the secretion of multiple bacteriocins by an ABC transporter.. |
| 34. | Fuqin Mu, Yoshimitsu Masuda, Takeshi Zendo, Hiroshi Ono, Hiroshi Kitagawa, Haruo Ito, Jiro Nakayama, Kenji Sonomoto, Biological function of a DUF95 superfamily protein involved in the biosynthesis of a circular bacteriocin, leucocyclicin Q, Journal of Bioscience and Bioengineering, 10.1016/j.jbiosc.2013.06.023, 117, 2, 158-164, 2014.02, [URL], Biological functions of a DUF95 superfamily protein in the biosynthesis gene cluster of a novel circular bacteriocin, leucocyclicin Q (LcyQ), were characterized in this paper. Sequence analysis and database search of the regions flanking the LcyQ structural gene lcyQ revealed four open reading frames (lcyR, lcyB, lcyC, and lcyD) related to bacteriocin biosynthesis. LcyD shares some similarity to the DUF95 superfamily proteins, often found in the biosynthetic gene clusters of circular bacteriocins. Mass spectrometry analysis showed accumulation of active mature LcyQ inside lcyD knockout cells. Heterologous expression of lcyD demonstrated that it confers robust immunity against LcyQ. Peptide release/binding assay revealed that the immunity could be attributed to the secretion of LcyQ to the cell exterior. Thus, the DUF95 superfamily protein has a dual function in the biosynthesis of LcyQ, as an immunity-associated transporter and as a secretion-aiding agent. Accumulation of mature LcyQ inside the cell in lcyD knockout strains, further implied that cyclization occurs within the cell. To the best of our knowledge, this is the first report on LcyQ cyclization inside the cell and the dual role of a DUF95 superfamily protein in circular bacteriocin biosynthesis.. |
| 35. | Dongdong Mu, Manuel Montalbán-López, Yoshimitsu Masuda, Oscar P. Kuipers, Zirex A novel zinc-regulated expression system for Lactococcus lactis, Applied and Environmental Microbiology, 10.1128/AEM.00866-13, 79, 14, 4503-4508, 2013.07, [URL], Here, we report a new zinc-inducible expression system for Lactococcus lactis, called Zirex, consisting of the pneumococcal repressor SczA and PczcD. PczcD tightly regulates the expression of green fluorescent protein in L. lactis. We show the applicability of Zirex together with the nisin-controlled expression system, enabling simultaneous but independent regulation of different genes.. |
| 36. | Rodney H. Perez, Kohei Himeno, Naoki Ishibashi, Yoshimitsu Masuda, Takeshi Zendo, Koji Fujita, Pongtep Wilaipun, Vichien Leelawatcharamas, Jiro Nakayama, Kenji Sonomoto, Monitoring of the multiple bacteriocin production by Enterococcus faecium NKR-5-3 through a developed liquid chromatography and mass spectrometry-based quantification system, Journal of Bioscience and Bioengineering, 10.1016/j.jbiosc.2012.06.003, 114, 5, 490-496, 2012.11, [URL], Enterococcus faecium NKR-5-3 produces four antimicrobial peptides referred here as enterocins NKR-5-3A, B, C and D. A two-step electrospray ionization-liquid chromatography and mass spectrometry (ESI-LC/MS)-based quantification system was developed to monitor its multiple bacteriocin production profiles, which is essential in understanding the complex production regulation mechanism of strain NKR-5-3. The developed ESI-LC/MS-based quantification system can easily monitor the multiple bacteriocin production of this strain. Using the developed system, the production of enterocin NKR-5-3B was found to be not as variable as those of the other enterocins in different cultivation media. Production of enterocin NKR-5-3B was also found to have a wider optimum incubation temperature (20-30°C) than enterocins NKR-5-3A, C and D (25°C). Furthermore, at least 2 nM of the bacteriocin-like inducing peptide, enterocin NKR-5-3D, regulated the production of NKR-5-3 enterocins except enterocin NKR-5-3B. These findings taken together suggest that enterocin NKR-5-3B has an independent production regulation mechanism from the other NKR-5-3 enterocins. The developed system could effectively pin-point the production profiles of the multiple bacteriocins of E. faecium NKR-5-3 under different fermentation conditions.. |
| 37. | Kohei Himeno, Koji Fujita, Takeshi Zendo, Pongtep Wilaipun, Naoki Ishibashi, Yoshimitsu Masuda, Fuminori Yoneyama, Vichien Leelawatcharamas, Jiro Nakayama, Kenji Sonomoto, Identification of enterocin NKR-5-3C, a novel class IIa bacteriocin produced by a multiple bacteriocin producer, Enterococcus faecium NKR-5-3, Bioscience, Biotechnology and Biochemistry, 10.1271/bbb.120089, 76, 6, 1245-1247, 2012.06, [URL], The structure of enterocin NKR-5-3C, an antilisterial bacteriocin produced by a multiple bacteriocin producer, Enterococcus faecium NKR-5-3, was determined. Enterocin NKR-5-3C is a novel class IIa bacteriocin that possesses an YGNGL motif sequence and two disulfide bridges in its structure. It is encoded on gene ent53C together with an 18-amino-acid-residue double glycine leader peptide.. |
| 38. | Naoki Ishibashi, Kohei Himeno, Koji Fujita, Yoshimitsu Masuda, Rodney Honrada Perez, Takeshi Zendo, Pongtep Wilaipun, Vichien Leelawatcharamas, Jiro Nakayama, Kenji Sonomoto, Purification and characterization of multiple bacteriocins and an inducing peptide produced by Enterococcus faecium NKR-5-3 from Thai fermented fish, Bioscience, Biotechnology and Biochemistry, 10.1271/bbb.110972, 76, 5, 947-953, 2012.05, [URL], Enterocins NKR-5-3A, B, C, and D were purified from the culture supernatant of Enterococcus faecium NKR-5-3 and characterized. Among the four purified peptides, enterocin NKR-5-3A (5242.3 Da) was identical to brochocin A, produced by Brochothrix campestris ATCC 43754, in mature peptides, and its putative synergistic peptide, enterocin NKR-5-3Z, was found to be encoded in ent53Z downstream of ent53A, encoding enterocin NKR-5-3A. Enterocin NKR-5-3B (6316.4Da) showed a broad antimicrobial spectrum, and enterocin NKR-5-3C (4512.8 Da) showed high activity against Listeria. Enterocin NKR-5-3D (2843.5 Da), showing high homology to an inducing peptide produced by Lactobacillus sakei 5, induced the production of the enterocins. The enterocins showed different antimicrobial spectra and intensities. E. faecium NKR-5-3 concomitantly produced enterocins NKR-5-3A, B, C, and D which probably belong to different classes of bacteriocins. Furthermore, NKR-5-3 production was induced by enterocin NKR-5-3D.. |
| 39. | Yoshimitsu Masuda, Takeshi Zendo, Kenji Sonomoto, New type non-lantibiotic bacteriocins Circular and leaderless bacteriocins, Beneficial microbes, 10.3920/BM2011.0047, 3, 1, 3-12, 2012.03, [URL], Bacteriocins are antimicrobial peptides that are ribosomally synthesised by bacteria. Bacteriocins produced by Gram-positive bacteria, including lactic acid bacteria, are under focus as the next generation of safe natural biopreservatives and as therapeutic alternatives to antibiotics. Recently, two novel types of non-lantibiotic class II bacteriocins have been reported with unique characteristics in their structure and biosynthesis mechanism. One is a circular bacteriocin that contains a head-to-tail structure in the mature form, and the other is a leaderless bacteriocin without an N-terminal extension in the precursor peptide. A circular structure can provide the peptide with remarkable stability against various stresses; indeed, circular bacteriocins are known to possess higher stability than general linear bacteriocins. Leaderless bacteriocins are distinct from general bacteriocins, because they do not contain N-terminal leader sequences, which are responsible for the recognition process during secretion and for inactivation of bacteriocins inside producer cells. Leaderless bacteriocins do not require any post-translational processing for activity. These two novel types of bacteriocins are promising antimicrobial compounds, and their biosynthetic mechanisms are expected to be applied in synthetic biology to design new peptides and for new mass production systems. However, many questions remain about their biosynthesis. In this review, we introduce recent studies on these types of bacteriocins and their potential to open a new world of antimicrobial peptides.. |
| 40. | Yoshimitsu Masuda, Takeshi Zendo, N. Sawa, R. H. Perez, Jiro Nakayama, Kenji Sonomoto, Characterization and identification of weissellicin Y and weissellicin M, novel bacteriocins produced by Weissella hellenica QU 13, Journal of Applied Microbiology, 10.1111/j.1365-2672.2011.05180.x, 112, 1, 99-108, 2012.01, [URL], 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 4968·40Da, 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.. |
| 41. | Yoshimitsu Masuda, Hiroshi Ono, Hiroshi Kitagawa, Haruo Ito, Fuqin Mu, Naruhiko Sawa, Takeshi Zendo, Kenji Sonomoto, Identification and characterization of Leucocyclicin Q, a novel cyclic Bacteriocin produced by Leuconostoc mesenteroides TK41401, Applied and Environmental Microbiology, 10.1128/AEM.06348-11, 77, 22, 8164-8170, 2011.11, [URL], The culture supernatant of Leuconostoc mesenteroides TK41401, isolated from Japanese pickles, possessed antimicrobial activity against broad range of a bacterial genera and particularly strong activity against Bacillus coagulans, the major contaminant of pickles. An antimicrobial peptide was purified in three chromatographic steps, and its molecular mass was determined to be 6,115.59 Da by electrospray ionization time-of-flight mass spectrometry (ESI-TOF MS). The primary structure of this peptide was determined by amino acid and DNA sequencing, and these analyses revealed that it was translated as a 63-residue precursor. This precursor showed high similarity to the precursor of lactocyclicin Q, a cyclic bacteriocin produced by Lactococcus sp. strain QU 12. The molecular weight calculated after cyclization, which was presumed to involve the same process as in lactocyclicin Q (between L3 and W63), agreed with that estimated by ESI-TOF MS. This peptide was proved to be a novel cyclic bacteriocin, and it was termed leucocyclicin Q. The antimicrobial spectrum of this bacteriocin clearly differed from that of lactocyclicin Q, even though their primary structures were quite similar. This is the first report of a cyclic bacteriocin produced by a strain of the genus Leuconostoc.. |
本データベースの内容を無断転載することを禁止します。