Studies on the mechanisms to expose virulence by a combined effort of capsule-positive and -negative Streptococcus suis

• Project/Area Number: 26660226
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Veterinary medical science
• Research Institution: The University of Tokyo
• Principal Investigator: Sekizaki Tsutomu 東京大学, 農学生命科学研究科, 教授 (70355163)
• Co-Investigator(Renkei-kenkyūsha): OSAKI MAKOTO 国立研究開発法人農業・食品産業技術総合研究機構, 動物衛生研究所, 主任研究員 (80355164) ; TAKAMATSU DAISUKE 国立研究開発法人農業・食品産業技術総合研究機構, 動物衛生研究所, 主任研究員 (60414728) ; OKURA MASATOSHI 国立研究開発法人農業・食品産業技術総合研究機構, 動物衛生研究所, 主任研究員 (60508315)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Project Status: Completed (Fiscal Year 2015)
• Budget Amount: ¥2,470,000 (Direct Cost: ¥1,900,000、Indirect Cost: ¥570,000); Fiscal Year 2015: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000); Fiscal Year 2014: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
• Keywords: 豚レンサ球菌 / 莢膜 / 心内膜炎 / 病原因子 / 遺伝子変異 / レンサ球菌

Outline of Final Research Achievements

Streptococcus suis was solely isolated from 59 out of 70 porcine endocarditis samples. Both of encapsulated and unencapsulated S. suis were found in the 26 samples, indicating coexistence of two phenotypes. Pairs of an encapsulated and an unencapsulated isolates were selected from each sample. The isolates in the same pair belonged to the same sequence type by MLST analysis. Whole genome sequencing showed that all the unencapsulated isolates had nonsynonymous mutations in the capsule polysaccharide synthesis (cps) genes. Genome-wide comparison of the isolates showed that the isolates in the same pair were the most closely resembled, and those originated from the same farm were more similar than those from different farms. In a few pairs, encapsulated isolates from the same farm were more similar than those of unencapsulated. These results suggest that the mutation in the cps genes occurred independently in different farms and some pairs occasionally persist to occur the next infection.

Research Products

• [Journal Article] Development of loop-mediated isothermal amplification to detect Streptococcus suis and its application to retail pork meat in Japan. (2015)
  • Author(s): Arai S, Tohya M, Yamada R, Osawa R, Nomoto R, Kawamura Y, Sekizaki T.
  • Journal Title: Int J Food Microbiol. Volume: 208 Pages: 35-42
  • DOI: 10.1016/j.ijfoodmicro.2015.05.008
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Estimating the burden of foodborne diseases in Japan. (2015)
  • Author(s): Kumagai, Y., Gilmour S., Ota, E., Momose, Y., Onishi, T., Bilano, V., Kasuga, F., Sekizaki, T., and Shibuya, K.
  • Journal Title: Bull. WHO. Volume: 93 Issue: 8 Pages: 540-549C
  • DOI: 10.2471/blt.14.148056
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] 豚に潜む危険な病原体と農場におけるリスク管理 (2015)
  • Author(s): 関崎 勉
  • Journal Title: 月刊PIG JOURNAL Volume: 18 Pages: 16-18
• [Journal Article] Reappraisal of the taxonomy of Streptococcus suis serotypes 20, 22 and 26: Streptococcus parasuis sp. nov. (2015)
  • Author(s): Nomoto R, Maruyama F, Ishida S, Tohya M, Sekizaki T, Osawa R.
  • Journal Title: Int J Syst Evol Microbiol. Volume: 65 Issue: Pt_2 Pages: 438-443
  • DOI: 10.1099/ijs.0.067116-0
  • Peer Reviewed
• [Journal Article] Development of a two-step multiplex PCR assay for typing of capsular polysaccharide synthesis gene clusters of Streptococcus suis (2014)
  • Author(s): Okura M, Lachance C, Osaki M, Sekizaki T, Maruyama F, Nozawa T, Nakagawa I, Hamada S, Rossignol C, Gottschalk M, Takamatsu D
  • Journal Title: J Clin Microbiol Volume: 52 Issue: 5 Pages: 1714-1719
  • DOI: 10.1128/jcm.03411-13
  • Peer Reviewed / Open Access
• [Journal Article] Capsule loss or death: The position of mutations among capsule genes sways the destiny of Streptococcus suis. (2014)
  • Author(s): Lakkitjaroen, N., Takamatsu, D., Okura, M., Sato, M., Osaki, M., and Sekizaki, T.
  • Journal Title: FEMS Microbiol. Lett. Volume: 353 Issue: 1 Pages: 46-54
  • DOI: 10.1111/1574-6968.12428
  • Peer Reviewed
• [Journal Article] Streptococcus suis Serotyping by a New Multiplex PCR. (2014)
  • Author(s): Kerdsin A, Akeda Y, Hatrongjit R, Detchawna U, Sekizaki T, Hamada S, Gottschalk M, Oishi K.
  • Journal Title: J Med Microbiol. Volume: 63 Issue: 6 Pages: 824-830
  • DOI: 10.1099/jmm.0.069757-0
  • Peer Reviewed
• [Journal Article] Latest developments on Streptococcus suis: an emerging zoonotic pathogen: part 1. (2014)
  • Author(s): Segura M, Zheng H, de Greeff A, Gao GF, Grenier D, Jiang Y, Lu C, Maskell D, Oishi K, Okura M, Osawa R, Schultsz C, Schwerk C, Sekizaki T, Smith H, Srimanote P, Takamatsu D, Tang J, Tenenbaum T, Tharavichitkul P, Hoa NT, Valentin-Weigand P, Wells JM, Wertheim H, Zhu B, Gottschalk M, Xu J.
  • Journal Title: Future Microbiol. Volume: 9 Issue: 4 Pages: 441-444
  • DOI: 10.2217/fmb.14.14
  • Peer Reviewed / Open Access
• [Journal Article] Latest developments on Streptococcus suis: an emerging zoonotic pathogen: part 2. (2014)
  • Author(s): Segura M, Zheng H, de Greeff A, Gao GF, Grenier D, Jiang Y, Lu C, Maskell D, Oishi K, Okura M, Osawa R, Schultsz C, Schwerk C, Sekizaki T, Smith H, Srimanote P, Takamatsu D, Tang J, Tenenbaum T, Tharavichitkul P, Hoa NT, Valentin-Weigand P, Wells JM, Wertheim H, Zhu B, Xu J, Gottschalk M.
  • Journal Title: Future Microbiol. Volume: 9 Issue: 5 Pages: 587-591
  • DOI: 10.2217/fmb.14.15
  • Peer Reviewed / Open Access
• [Journal Article] Development of an appropriate PCR system for the reclassification of Streptococcus suis. (2014)
  • Author(s): Ishida S, Tien LHT, Osawa R, Tohya M, Nomoto R, Kawamura Y, Takahashi T, Kikuchi N, Kikuchi K, Sekizaki T.
  • Journal Title: J Microbiol Meth Volume: 107 Pages: 66-70
  • DOI: 10.1016/j.mimet.2014.09.003
  • Peer Reviewed
• [Presentation] 豚レンサ球菌の特定集団で見られた莢膜欠失による自然形質転換能の上昇 (2016)
  • Author(s): 大倉 正稔，大崎 慎人，関崎 勉，高松 大輔
  • Organizer: 第89回日本細菌学会総会
  • Place of Presentation: 大阪国際交流センター
  • Year and Date: 2016-03-23
• [Presentation] Recovery of Streptococcus suis serotype 2 capsule and its virulence in vivo. (2016)
  • Author(s): 高松 大輔，大倉 正稔，大崎 慎人，関崎 勉
  • Organizer: 第89回日本細菌学会総会
  • Place of Presentation: 大阪国際交流センター
  • Year and Date: 2016-03-23
• [Presentation] CRISPR を保有するバクテリオファージの系統学的普遍性 (2016)
  • Author(s): 渡辺 孝康，野澤 孝志，丸山 史人，中川 一路，関崎 勉
  • Organizer: 第89回日本細菌学会総会
  • Place of Presentation: 大阪国際交流センター
  • Year and Date: 2016-03-23
• [Presentation] Streptococcus suis の無莢膜化機序の比較ゲノム解析 (2016)
  • Author(s): 遠矢 真理，渡辺 孝康，丸山 史人，新井 沙倉，大田 篤，中川一路，関崎 勉
  • Organizer: 第89回日本細菌学会総会
  • Place of Presentation: 大阪国際交流センター
  • Year and Date: 2016-03-23
• [Presentation] Streptococcus suis特異的real-time PCR法の開発と豚個体・飼料環境への応用 (2016)
  • Author(s): 新井 沙倉，Hyujung Kim, 遠矢 真理，渡辺 孝康，鈴木詠律子，山田良子, 堂崎真一, 関崎 勉
  • Organizer: 第89回日本細菌学会総会
  • Place of Presentation: 大阪国際交流センター
  • Year and Date: 2016-03-23
• [Presentation] 莢膜欠失によって獲得する異なる病原性：Streptococcus suis の場合 (2016)
  • Author(s): 関崎 勉，Nattakan Meekhanon，遠矢 真理，新井 沙倉，高松大輔，大倉 正稔，大崎 慎人，渡辺 孝康，丸山 史人，中川 一路
  • Organizer: 第89回日本細菌学会総会
  • Place of Presentation: 大阪国際交流センター
  • Year and Date: 2016-03-23
• [Presentation] 豚心内膜炎病変部に共存したStreptococcus suis無莢膜株および有莢膜株の遺伝的近縁性とゲノム変異についての解析 (2015)
  • Author(s): 遠矢真理、新井沙倉、丸山史人、渡辺孝康、大田 篤、大倉正稔、高松大輔、大崎慎人、中川一路、関崎 勉
  • Organizer: 第158回日本獣医学会学術集会
  • Place of Presentation: 北里大学獣医学部
  • Year and Date: 2015-09-07
• [Presentation] 豚心内膜炎病変部に共存したStreptococcus suis無莢膜株および有莢膜株の起源の同一性について (2015)
  • Author(s): 遠矢真理、新井沙倉、丸山史人、大田篤、大倉正稔、高松大輔、中川一路、関崎 勉
  • Organizer: 第47回レンサ球菌研究会
  • Place of Presentation: 宮崎市ひまわり荘
  • Year and Date: 2015-07-03
• [Presentation] 市販豚肉・内臓肉からのStreptococcus suis分離と豚肉汚染ルートの推定 (2015)
  • Author(s): 新井沙倉、遠矢真理、山田良子、野本竜平、大澤 朗、関崎 勉
  • Organizer: 第47回レンサ球菌研究会
  • Place of Presentation: 宮崎市ひまわり荘
  • Year and Date: 2015-07-03
• [Presentation] ゲノム解析から明らかとなったStreptococcus suisにおける曖昧な種の境界及び進化の鍵となるスポット (2015)
  • Author(s): 大倉正稔、野澤孝志、渡辺孝康、中川一路、高松大輔、大﨑慎人、関崎 勉、浜田茂幸、丸山史人
  • Organizer: 第88回日本細菌学会総会
  • Place of Presentation: 長良川国際会議場、岐阜県
  • Year and Date: 2015-03-26 – 2015-03-28
• [Presentation] 豚心内膜炎病変部に共存するStreptococcus suis無莢膜株および有莢膜株の遺伝学的性状 (2015)
  • Author(s): 遠矢真理、新井沙倉、大倉正稔、高松大輔、大﨑慎人、関崎 勉
  • Organizer: 第88回日本細菌学会総会
  • Place of Presentation: 長良川国際会議場、岐阜県
  • Year and Date: 2015-03-26 – 2015-03-28
• [Presentation] 日本の市販豚肉・内臓肉からのStreptococcus suisの検出と分離 (2015)
  • Author(s): 新井沙倉、遠矢真理、野本竜平、大澤 朗、関崎 勉
  • Organizer: 第88回日本細菌学会総会
  • Place of Presentation: 長良川国際会議場、岐阜県
  • Year and Date: 2015-03-26 – 2015-03-28
• [Presentation] 豚レンサ球菌の分類再検討とそれに対応した検出法の開発と応用 (2015)
  • Author(s): 関崎 勉
  • Organizer: 平成26年度日本獣医師会年次大会
  • Place of Presentation: 岡山コンベンションセンター、岡山県
  • Year and Date: 2015-02-13 – 2015-02-15
  • Invited
• [Presentation] Coexistence of encapsulated and unencapsulated Streptococcus suis cells in a single clinical specimen of porcine endocarditis. (2014)
  • Author(s): Tohya M, Ishida S, Okura M, Takamatsu D, Osaki M, Sekizaki T.
  • Organizer: XIX Lancefield International Symposium on Streptococci and Streptococcal Diseases.
  • Place of Presentation: Buenos Aires, Argentina
  • Year and Date: 2014-11-09 – 2014-11-12
• [Presentation] Detection and isolation of Streptococcus suis from retail pork meat and organs in Japan with Loop-mediated isothermal amplification. (2014)
  • Author(s): Ishida S, Tohya M, Nomoto R, Osawa R, Sekizaki T.
  • Organizer: XIX Lancefield International Symposium on Streptococci and Streptococcal Diseases.
  • Place of Presentation: Buenos Aires, Argentina
  • Year and Date: 2014-11-09 – 2014-11-12
• [Presentation] Genome sequencing of miscellaneous strains revealed the distinctive genes of the species “Streptococcus suis” and potentially hazardous populations for human. (2014)
  • Author(s): Okura M, Nozawa T, Watanabe T, Nakagawa I, Takamatsu D, Osaki M, Sekizaki T, Kumagai M, Gottschalk M, Hamada S, Maruyama F.
  • Organizer: XIX Lancefield International Symposium on Streptococci and Streptococcal Diseases.
  • Place of Presentation: Buenos Aires, Argentina
  • Year and Date: 2014-11-09 – 2014-11-12
• [Presentation] 豚心内膜炎病変部での有莢膜および無莢膜Streptococcus suisの共存 (2014)
  • Author(s): 遠矢真理、石田沙倉、大倉正稔、高松大輔、大﨑慎人、関崎 勉
  • Organizer: 第157回日本獣医学会学術集会
  • Place of Presentation: 北海道大学、札幌、北海道
  • Year and Date: 2014-09-09 – 2014-09-12
• [Presentation] Streptococcus suis検出のための信頼できるPCR法の開発 (2014)
  • Author(s): 石田沙倉、Le Hong Thuy Tien、大澤 朗、遠矢真理、野本竜平、河村好章、高橋樹史、菊池直哉、菊池 賢、関崎 勉
  • Organizer: 第157回日本獣医学会学術集会
  • Place of Presentation: 北海道大学、札幌、北海道
  • Year and Date: 2014-09-09 – 2014-09-12
• [Presentation] ゲノム比較により明らかになったStreptococcus suisに特徴的な遺伝子 (2014)
  • Author(s): 大倉正稔、高松大輔、野澤孝志、渡辺孝康、中川一路、大崎慎人、関崎 勉、浜田茂幸、丸山史人
  • Organizer: 第46回レンサ球菌研究会
  • Place of Presentation: 東京大学、東京
  • Year and Date: 2014-06-27 – 2014-06-28
• [Presentation] Streptococcus suis血清型20, 22, 及び26のゲノム配列に基づく分類学的再検討 (2014)
  • Author(s): 野本竜平、石田沙倉、遠矢真理、関崎 勉、丸山史人、大澤 朗
  • Organizer: 第46回レンサ球菌研究会
  • Place of Presentation: 東京大学、東京
  • Year and Date: 2014-06-27 – 2014-06-28
• [Presentation] Streptococcus suisの再分類に対応するLAMP法の開発と豚肉検査への応用 (2014)
  • Author(s): 石田沙倉、遠矢真理、野本竜平、大澤 朗、関崎 勉
  • Organizer: 第46回レンサ球菌研究会
  • Place of Presentation: 東京大学、東京
  • Year and Date: 2014-06-27 – 2014-06-28
• [Presentation] 同一個体の豚心内膜炎由来Streptococcus suisの莢膜産生性の解析 (2014)
  • Author(s): 遠矢真理、石田沙倉、大倉正稔、高松大輔、大崎慎人、新井紘胤、関崎 勉
  • Organizer: 第46回レンサ球菌研究会
  • Place of Presentation: 東京大学、東京
  • Year and Date: 2014-06-27 – 2014-06-28