Ecological and molecular-epidemiological studies of Vibrio cholerae related bacteria in Indian Subcontinent

• Project/Area Number: 14406006
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 海外学術
• Research Field: Bacteriology (including Mycology)
• Research Institution: OKAYAMA UNIVERSITY
• Principal Investigator: SHINODA Sumio OKAYAMA UNIVERSITY, Graduate School of Natural Science and Technology, Professor, 大学院・自然科学研究科, 教授 (50029782)
• Co-Investigator(Kenkyū-buntansha): OKAMOTO Keinosuke OKAYAMA UNIVERSITY, Faculty of Pharmaceutical Sciences, Professor, 薬学部, 教授 (70131183) ; TOMOCHIKA Ken-ichi Okayama Gakuin University, Faculty of Human Life, Professor, 人間生活学部, 教授 (00093691) ; MIYOSHI Shin-ichi OKAYAMA UNIVERSITY, Graduate School of Natural Science and Technology, Associate Professor, 大学院・自然科学研究科, 助教授 (60182060)
• Project Period (FY): 2002 – 2004
• Project Status: Completed (Fiscal Year 2004)
• Budget Amount: ¥14,600,000 (Direct Cost: ¥14,600,000); Fiscal Year 2004: ¥3,000,000 (Direct Cost: ¥3,000,000); Fiscal Year 2003: ¥4,700,000 (Direct Cost: ¥4,700,000); Fiscal Year 2002: ¥6,900,000 (Direct Cost: ¥6,900,000)
• Keywords: Cholera / Vibrios / Diarrheal disease / Indian-subcon / Ecology / Molecular epidemiology

Research Abstract

Vibrio cholerae colonizes aquatic environments in Indian-subcontinent, especially in Ganges Basin, and causes cholera epidemics periodically. Of the 206 serovars of V.cholerae, only O1 and 139 cause epidemic cholera, whereas non-O1/non-O139 strains do not, although sporadic diarrheal cases are observed. To clarify epidemic feature of cholera in these area, V.cholerae strains were isolated from from environmental and clinical origins and analysed.
V.cholerae isolates from both origins in the Bengal region were analyzed with particular emphasis on the molecular epidemiological feature. Presence of the virulence genes (ctxA,tcpA and toxR) in the isolates was analyzed by PCR(polymerase chain reaction) method. PFGE (pulsed-field gel electrophoresis) was performed to determine the clonal relationships between clinical and environmental strains. O1 and O139 strains from both clinical and environmental sources were all positive for the three virulence genes while nonO1/non-O139 strains from both sources were all negative for ctxA and tcpA, except a strain, but positive for toxR. PFGE patterns of recent isolates of O1 and O139 were similar in each serovar regardless of origins, although comparison with past isolates showed some differences. An exceptional non-O1/non-O139 strain. was positive for ctxA and tcpA of classical type. These results indicate that there is a clonal relationship between clinical and environmental strains and the aquatic environments serve as reservoirs of toxigenic V.cholerae.

Research Products

• [Journal Article] A variant type of Vibrio cholerae SXT element in a multidrug-resistant strain of Vibrio fluvialis. (2005)
  • Author(s): Ahmed, A.M., Shinoda, S., Shimamoto, T.
  • Journal Title: FEMS Microbiology Letter 242 Pages: 241-247
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] A variant type of Vibrio cholerae SXT element in a mutidrug-resistant str5ain of VIbrio fluvialis. (2005)
  • Author(s): Ahmed, A.M., Shinoda, S., Shimamoto, T.
  • Journal Title: FEMS Microbiol.Lett. 242 Pages: 241-247
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] A variant type of Vibrio cholerae SXT element in a mutidrug-resistant strain of VIbrio fluvialis. (2005)
  • Author(s): Ahmed, A.M., Shinoda, S., Shimamoto, T.
  • Journal Title: FEMS Microbiol.Lett. 242 Pages: 241-247
• [Journal Article] New aminoglycoside acetyltransferase gene, aac(3)-ID, in a class 1 integron from a multiresistant strain of Vibrio fluvialis isolated from an infant aged 6 months (2004)
  • Author(s): Ahmed, A.M., Nakagawa, T., Arakawa, E., Ramamurthy, T., Shinoda, S., Shimamoto, T.
  • Journal Title: Journal of Antimicrobial Chemotherapy 53 Pages: 947-951
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] Distribution of virulence-associated genes in Vibrio mimicus isolates from clinical and environmental origins. (2004)
  • Author(s): Shinoda, S., Nakagawa, T., Shi, L., Bi, K., Kanoh, Y., Tomochika, K., Miyoshi, S., Shimada, T.
  • Journal Title: Microbiology and Immunology 48 Pages: 547-551
  • NAID: 10013297602
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] New aminoglycoside acetyltransferase gene, aac(3)-ID, in a class 1 integron from a multiresistant st5rain of Vibrio fluvialis isolated from an infant aged 6 months. (2004)
  • Author(s): Ahmed, A.M., Nakagawa, T., Arakawa, E., Ramamurthy, T., Shinoda, S., Shimamoto, T.
  • Journal Title: J.Antimicrobial Chemother 53 Pages: 947-951
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] Distribution of virulence-associated genes in Vibrio mimicus isolates from clinical and environmental origins. (2004)
  • Author(s): Shinoda, S., Nakagawa, T., Shi, L., Bi, K., Kanoh, Y., Tomochika, K., Miyoshi, S., Shimada, T.
  • Journal Title: Microbiol.Immunol. 48 Pages: 547-551
  • NAID: 10013297602
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] Distribution of virulence-associated genes in Vibrio mimicus isolates from clinical and environmental origins. (2004)
  • Author(s): Shinoda, S., Nakagawa, T., Shi, L., Bi, K., Kanoh, Y., Tomochika, K., Miyoshi, S., Shimada, T.
  • Journal Title: Microbiol.Immunol 48 Pages: 547-551
  • NAID: 10013297602
• [Journal Article] Studies on pathogenic Vibrio parahaemolyticus during a warm weather season in the Seto-inland sea, Japan. (2003)
  • Author(s): Alam, Md.J., Miyoshi, S., Shinoda, S.
  • Journal Title: Environmental Microbiology 5 Pages: 706-710
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] Studies on pathogenic Vibrio parahaemolyticus during a warm weather season in the Seto-inland sea, Japan. (2003)
  • Author(s): Alam, Md.J., Miyoshi, S., Shinoda, S.
  • Journal Title: Env.Microbiol. 5 Pages: 706-710
  • Description: 「研究成果報告書概要(欧文)」より
• [Publications] Watanabe, H., Miyoshi, S., Kawase, T., Tomochika, K., Shinoda, S.: "High growing ability of Vibrio vulnificus biotype 1 is essential for production of a toxic metalloprotease causing systemic diseases in humans."Microbiol.Pathog.. 36. 117-123 (2004)
• [Publications] Ahmed, A.M., Nakagawa, T., Arakawa, E., Ramamurthy, T., Shinoda, S., Shimamoto, S.: "New Aminoglycoside Acetyltransferase Gene, aac(3)-Id, and aadA7 in Class I Integron from a Multiresistant Strain of Vibrio fluvialis Isolated from a Six-Month Infant with a Cholera-like Diarrhea in India"Journal of Antimicrobial Chemotherapy. (In press). (2004)
• [Publications] Bi, K., Miyoshi, S., Tomochika, K., Shinoda, S.: "Detection of virulence associated genes in clinical strains of Vibrio mimicus"Microbiology and Immunology. 45. 613-616 (2002)