Faculty Profiles - SHIBAYAMA Keigo

Papers - SHIBAYAMA Keigo

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Emergence of fosfomycin-resistant isolates of Shiga-like toxin-producing Escherichia coli O26 Reviewed Open Access

Horii T., Kimura T., Sato K., Shibayama K., Ohta M.

Antimicrobial Agents and Chemotherapy Vol. 43 ( 4 ) page： 789 - 793 1999.4

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Antimicrobial Agents and Chemotherapy

We evaluated the susceptibilities of 129 Shiga-like toxin-producing Escherichia coli (STEC) isolates to various antibiotics. The numbers of isolates for which MICs were high (≥128 μg/ml) were as follows: 5 for fosfomycin, 14 for ampicillin, 1 for cefaclor, 6 for kanamycin, 22 for tetracycline, and 2 for doxycycline. For two isolates of STEC O26 MICs of fosfomycin were high (1,024 and 512 μg/ml, respectively). Conjugation experiments and glutathione S-transferase assays suggested that the fosfomycin resistance in these isolates was determined not by a plasmid but chromosomally. The amount of active intracellular fosfomycin in these STEC isolates was 100- to 200-fold less than that in E. coli C600 harboring pREFTT47B408 in the presence of either L-α-glycerophosphate or glucose-6- phosphate. Cloning, sequencing, and Northern blot analysis demonstrated that the transcriptional level of the murA gene encoding UDP-N-acetylglucosamine enolpyruvoyl transferase in these isolates was greater than that in E. coli C600. Our results suggest that the fosfomycin resistance in these STEC isolates is due to concurrent effects of alteration of the glpT and/or uhp transport systems and of the enhanced transcription of the murA gene.

DOI： 10.1128/aac.43.4.789

Scopus

Growth Conditions of and Emetic Toxin Production by Bacillus cereus in a Defined Medium with Amino Acids Reviewed

AGATA Norio, OHTA Michio, MORI Masashi, SHIBAYAMA Keigo

MICROBIOLOGY and IMMUNOLOGY Vol. 43 ( 1 ) page： 15 - 18 1999.1

Language：English Publishing type：Research paper (scientific journal) Publisher：Center For Academic Publications Japan

The growth and emetic toxin (cereulide) production of Bacillus cereus strains in defined culture media were studied. We found that a fully synthetic medium (CADM) allowed the production of emetic toxin and the addition of glucose enhanced it. By subtracting each amino acid from CADM, we found that only three amino acids, valine, leucine and threonine, were essential for growth and toxin production by B. cereus. The addition of high levels (50mM) of leucine, isoleucine and glutamlc acid decreased the toxin production. Other amino acids had no effect at this concentration.

CiNii Research

Antibacterial Activities of New Synthetic Divalent Cation Chelators Reviewed Open Access

Ashoori Mandana, Ohta Michio, Ohsuka Shinji, Shibayama Keigo, Horii Toshinobu, Ueda Minoru, Kurosaki Hiromasa

Japanese Journal of Microbiology Vol. 43 ( 4 ) page： 311 - 316 1999

Language：English Publishing type：Research paper (scientific journal) Publisher：Center For Academic Publications Japan

A series of new synthetic ligand compounds which chelate divalent cations was examined for the antibacterial activities of the compounds. Only 2 of 14 synthetic chelators, 9-trans-anthryl-1, 4, 8, 11-tetraazatetradecane (No. 6) and bis(2-pyridyl)methylamine (No. 13) showed antibacterial activities, whereas none of the diamines, hydrophilic triamines nor tetramines showed antibacterial activities. Chelators No. 6 and No. 13 inhibited the growth of both Gram-negative and -positive bacteria at doses of 25-200μg/ml, comparable to those of common antibiotics such as polymixin B, fosfomycin and macrolides. Ethylenediaminetetraacetate (EDTA) potentiated these antibacterial activities, whereas an inhibitory effect of Mg2+ on the MICs of these chelators was observed. Moreover, these chelators enhanced the leakage of periplasmic β-lactamase. It is therefore suggested that chelators No. 6 and No. 13 disrupt both the membranes and cytoplasmic functions of bacteria, resulting in cell death.

DOI： 10.1111/j.1348-0421.1999.tb02410.x

CiNii Research

Are Autoantibodies against Lewis Antigens Involved in the Pathogenesis of Helicobacter pylori-Induced Peptic Ulcers? Reviewed Open Access

Kamiya Kenji, Arisawa Tomiyasu, Goto Hidemi, Shibayama Keigo, Horii Toshinobu, Hayakawa Tetsuo, Ohta Michio

Japanese Journal of Microbiology Vol. 43 ( 5 ) page： 403 - 408 1999

Language：English Publishing type：Research paper (scientific journal) Publisher：Center For Academic Publications Japan

We examined whether anti-Lewis x (Lex) and y (Ley) autoantibodies affect the pathogenesis of Helicobacter pylori-induced peptic ulcers. Of 11 patients with peptic ulcers, 10 patients had both anti-Lex and -Ley immunoglobulin G (IgG) antibodies, and 1 patient had only anti-Lex antibody. After successful eradication, we measured the serum titer of anti-Lex and -Ley antibodies. Six patients had a reduction of the titers of anti-Lex and/or -Ley antibodies, whereas no notable changes were detected in 5 patients in the follow-up. This result suggests that anti-Lex and -Ley autoantibodies had no critical role in the development of H. pylori-induced peptic ulcer.

Open Access

CiNii Research

Antibacterial activities of new synthetic divalent cation chelators Reviewed Open Access

Ashoori M., Ohta M., Ohsuka S., Shibayama K., Horii T., Ueda M., Kurosaki H.

Microbiology and Immunology Vol. 43 ( 4 ) page： 311 - 316 1999

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Microbiology and Immunology

A series of new synthetic ligand compounds which chelate divalent cations was examined for the antibacterial activities of the compounds. Only 2 of 14 synthetic chelators, 9-trans-anthryl-1, 4, 8, 11-tetraazatetradecane (No. 6) and bis(2-pyridyl)methylamine (No. 13) showed antibacterial activities, whereas none of the diamines, hydrophilic triamines nor tetramines showed antibacterial activities. Chelators No. 6 and No. 13 inhibited the growth of both Gram-negative and -positive bacteria at doses of 25-200 μg/ml, comparable to those of common antibiotics such as polymixin B, fosfomycin and macrolides. Ethylenediaminetetraacetate (EDTA) potentiated these antibacterial activities, whereas an inhibitory effect of Mg2+ on the MICs of these chelators was observed. Moreover, these chelators enhanced the leakage of periplasmic β-lactamase. It is therefore suggested that chelators No. 6 and No. 13 disrupt both the membranes and cytoplasmic functions of bacteria, resulting in cell death.

DOI： 10.1111/j.1348-0421.1999.tb02410.x

Scopus

Are autoantibodies against Lewis antigens involved in the pathogenesis of Helicobacter pylori-induced peptic ulcers? Reviewed Open Access

Kamiya K., Arisawa T., Goto H., Shibayama K., Horii T., Hayakawa T., Ohta M.

Microbiology and Immunology Vol. 43 ( 5 ) page： 403 - 408 1999

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Microbiology and Immunology

We examined whether anti-Lewis x (Le(x)) and y (Le(y)) autoantibodies affect the pathogenesis of Helicobacter pylori-induced peptic ulcers. Of 11 patients with peptic ulcers, 10 patients had both anti-Le(x) and -Le(y) immunoglobulin G (IgG) antibodies, and 1 patient had only anti-Le(x) antibody. After successful eradication, we measured the serum titer of anti- Le(x) and -Le(y) antibodies. Six patients had a reduction of the titers of anti-Le(x) and/or -Le(y) antibodies, whereas no notable changes were detected in 5 patients in the follow-up. This result suggests that anti-Le(x) and - Le(y) autoantibodies had no critical role in the development of H. pylori- induced peptic ulcer.

DOI： 10.1111/j.1348-0421.1999.tb02423.x

Scopus

Growth Conditions of and Emetic Toxin Production by Bacillus cereus in a Defined Medium with Amino Acids Reviewed Open Access

Agata Norio, Ohta Michio, Mori Masashi, Shibayama Keigo

Japanese Journal of Microbiology Vol. 43 ( 1 ) page： 15 - 18 1999

Language：English Publishing type：Research paper (scientific journal) Publisher：Center For Academic Publications Japan

Open Access

CiNii Research

Growth conditions of and emetic toxin production by Bacillus cereus in a defined medium with amino acids Reviewed

Agata N., Ohta M., Mori M., Shibayama K.

Microbiology and Immunology Vol. 43 ( 1 ) page： 15 - 18 1999

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Microbiology and Immunology

The growth and emetic toxin (cereulide) production of Bacillus cereus strains in defined culture media were studied. We found that a fully synthetic medium (CADM) allowed the production of emetic toxin and the addition of glucose enhanced it. By subtracting each amino acid from CADM, we found that only three amino acids, valine, leucine and threonine, were essential for growth and toxin production by B. cereus. The addition of high levels (50 mM) of leucine, isoleucine and glutamic acid decreased the toxin production. Other amino acids had no effect at this concentration.

DOI： 10.1111/j.1348-0421.1999.tb02367.x

Scopus

Streptococcal pyrogenic exotoxin F (SpeF) causes permeabilization of lung blood vessels Reviewed Open Access

Matsumoto M., Ishikawa N., Saito M., Shibayama K., Horii T., Sato K., Ohta M.

Infection and Immunity Vol. 67 ( 9 ) page： 4307 - 4311 1999

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Infection and Immunity

Acute respiration distress syndrome (ARDS) is a typical complication in toxic shock-like syndrome (TSLS) caused by Streptococcus pyogenes. An isolated perfused rat lung model was used to identify the causative agent of ARDS in TSLS in this study. Some crude preparations separated from the culture supernatants of S. pyogenes isolates caused rapid increases in the weight of perfused lungs, indicating vascular permeabilization. Six samples from M type 1 and 3 isolates from TSLS and pharyngitis patients showed strong permeabilization activity, whereas preparations from isolates of other M types (although the number of isolates examined was limited) were negative. The active substance was purified to a single band by sodium dodecyl sulfate- polyacrylamide gel electrophoresis using various columns, and the N-terminal amino acid sequence was determined. The resultant sequence of eight amino acids was identical to SpeF (mitogenic factor). Moreover, the vascular permeabilization activity of the purified band was abolished with anti-SpeF antiserum prepared by immunizing with the purified SpeF. This activity was also neutralized by the antiserum prepared by immunizing with a synthetic peptide derived from the published SpeF sequence. These results suggested that streptococcal SpeF is a major cause of permeabilization of lung blood vessels and sufficient for the pathogenesis of ARDS under the conditions of TSLS caused by S. pyogenes.

DOI： 10.1128/iai.67.9.4307-4311.1999

Scopus

Heterogeneity of Phenotypic and Genotypic Traits Including Organic-Acid Resistance in Escherichia coli O157 Isolates Reviewed Open Access

HORII Toshinobu, BARUA Soumitra, KIMURA Taku, KASUGAI Shin, SATO Kumiko, SHIBAYAMA Keigo, ICHIYAMA Satoshi, OHTA Michio

MICROBIOLOGY and IMMUNOLOGY Vol. 42 ( 12 ) page： 871 - 874 1998.12

Language：English Publishing type：Research paper (scientific journal) Publisher：Center For Academic Publications Japan

We undertook an epidemiologic study for the sensitivity of both Shiga-like toxin (Slt)-producing Escherichia coli (STEC) O157 and non-STEC O157 strains isolated from different patients with diarrhea to hydrochloric acid (HCl) and organic acids such as acetate, propionate, butyrate and lactate, and other pathogenic factors. The E. coli O157 isolates examined showed a wide variety of organic-acid susceptibility patterns. E. coli O157 isolates resistant to HCl or acetate were found more frequently than those resistant to other organic acids. These isolates also showed diverse pathogenicity patterns for the presence of the virulence genes, antibiotic susceptibility and plasmid profile.

DOI： 10.1111/j.1348-0421.1998.tb02363.x

CiNii Research

Conserved structural regions involved in the catalytic mechanism of Escherichia coli K-12 WaaO (RfaI) Reviewed Open Access

Shibayama K., Ohsuka S., Tanaka T., Arakawa Y., Ohta M.

Journal of Bacteriology Vol. 180 ( 20 ) page： 5313 - 5318 1998.10

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Journal of Bacteriology

Escherichia coli K-12 WaaO (formerly known as RfaI) is a nonprocessive α-1,3 glucosyltransferase, involved in the synthesis of the R core of lipopolysaccharide. By comparing the amino acid sequence of WaaO with those of 11 homologous α-glycosyltransferases, four strictly conserved regions, I, II, III, and IV, were identified. Since functionally related transferases are predicted to have a similar architecture in the catalytic sites, it is assumed that these four regions are directly involved in the formation of α- glycosidic linkage from α-linked nucleotide diphospho-sugar donor. Hydrophobic cluster analysis revealed a conserved domain at the N termini of these α-glycosyltransferases. This domain was similar to that previously reported for β-glycosyltransferases. Thus, this domain is likely to be involved in the formation of β-glycosidic linkage between the donor sugar and the enzyme at the first step of the reaction. Site-directed mutagenesis analysis of E. coli K-12 WaaO revealed four critical amino acid residues.

DOI： 10.1128/jb.180.20.5313-5318.1998

Scopus

Heterogeneity of Phenotypic and Genotypic Traits Including Organic-Acid Resistance in Escherichia coli O157 Isolates Reviewed Open Access

Horii Toshinobu, Barua Soumitra, Kimura Taku, Kasugai Shin, Sato Kumiko, Shibayama Keigo, Ichiyama Satoshi, Ohta Michio

Japanese Journal of Microbiology Vol. 42 ( 12 ) page： 871 - 874 1998

Language：English Publishing type：Research paper (scientific journal) Publisher：Center For Academic Publications Japan

Open Access

CiNii Research

Nosocomial spread of cephem-resistant Escherichia coli strains carrying multiple Toho-1-like β-lactamase genes Reviewed Open Access

Yagi T., Kurokawa H., Senda K., Ichiyama S., Ito H., Ohsuka S., Shibayama K., Shimokata K., Kato N., Ohta M., Arakawa Y.

Antimicrobial Agents and Chemotherapy Vol. 41 ( 12 ) page： 2606 - 2611 1997.12

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Antimicrobial Agents and Chemotherapy

Escherichia coli HKY56, which demonstrated resistance to various β- lactams except carbapenems, was isolated from the throat swab of an inpatient in 1994. Conjugal transfer of cephem resistance from HKY56 to E. coli CSH2 was not successful. Three cefotaxime-resistant E. coli clones harboring plasmid pMRE001, pMRE002, or pMRE003, each of which carried a 3.4-, 5.8-, or 6.2-kb EcoRI fragment insert, respectively, were obtained from HKY56. Although restriction analysis suggested their different origins, these clones showed similar profiles of resistance to various β-lactams. The sequence of 10 amino acid residues at the N terminus of β-lactamase purified from E. coli HB101(pMRE001) was identical to that of Toho-1. This Toho-1-like β- lactamase-1 (TLB-1) was able to hydrolyze cefoperazone and cefotaxime efficiently, but it failed to hydrolyze cephamycins. A Toho-1-specific DNA probe was hybridized with three distinct EcoRI fragments derived from the chromosomal DNA of strain HKY56, and these fragments corresponded to DNA inserts carried by pMRE001, pMRE002, and pMRE003, respectively. PCR and Southern hybridization analysis suggested that all six cephem-resistant E. coli strains, strains HKY273, HKY285, HKY288, HKY305, HKY316, and HKY335, which were isolated in 1996 at the same hospital where strain HKY56 had been isolated, also possessed multiple Toho-1-like β-lactamase (TLB) genes, and the hybridization patterns obtained with the Toho-1-specific probe were quite similar among these six isolates. The DNA fingerprinting patterns observed by pulsed-field gel electrophoresis revealed that among the E. coli isolates tested, all isolates except HKY56 possessed a similar genetic background. These findings suggested that E. coli strains that carry chromosomally multiplied TLB genes may have been proliferating and transmitted among patients in the same hospital.

DOI： 10.1128/aac.41.12.2606

Scopus

RobA-Induced Multiple Antibiotic Resistance Largely Depends on the Activation of the AcrAB Efflux Reviewed Open Access

TANAKA Toshihiko, HORII Toshinobu, SHIBAYAMA Keigo, SATO Kumiko, OHSUKA Shinji, ARAKAWA Yoshichika, YAMAKI Ken-ichi, TAKAGI Kenzo, OHTA Michio

MICROBIOLOGY and IMMUNOLOGY Vol. 41 ( 9 ) page： 697 - 702 1997.9

Language：English Publishing type：Research paper (scientific journal) Publisher：Center For Academic Publications Japan

RobA is a member of the XylS/AraC subfamily of DNA binding proteins, and when overexpressed, it induces multiple antibiotic resistance in Escherichia coli. In this study, we introduced a multicopy robA plasmid (pMEP1) and its derivative into OmpF mutants and an AcrAB-deficient mutant. We found that a decrease in susceptibility to multiple antibiotics in these OmpF mutants when pMEP1 was introduced did not depend on OmpF porin expression. Interestingly, a ΔompF mutant (TK007) became more sensitive when pMEP1 was introduced. Moreover, no effect of RobA on the induction of multiple antibiotic resistance in an acrA1- mutant was observed. Therefore, we conclude that the multiple antibiotic resistance induced by the overexpression of RobA largely depends on the activation of the AcrAB efflux, as well as the activation of micF.

DOI： 10.1111/j.1348-0421.1997.tb01913.x

CiNii Research

RobA-induced multiple antibiotic resistance largely depends on the activation of the AcrAB efflux Reviewed Open Access

Tanaka T., Horii T., Shibayama K., Sato K., Ohsuka S., Arakawa Y., Yamaki K.I., Takagi K., Ohta M.

Microbiology and Immunology Vol. 41 ( 9 ) page： 697 - 702 1997

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Microbiology and Immunology

RobA is a member of the XyIS/AraC subfamily of DNA binding proteins, and when overexpressed, it induces multiple antibiotic resistance in Escherichia coli. In this study, we introduced a multicopy robA plasmid (pMEP1) and its derivative into OmpF mutants and an AcrAB-deficient mutant. We found that a decrease in susceptibility to multiple antibiotics in these OmpF mutants when pMEP1 was introduced did not depend on OmpF porin expression. Interestingly, a ΔompF mutant (TK007) became more sensitive when pMEP1 was introduced. Moreover, no effect of RobA on the induction of multiple antibiotic resistance in an acrA1- mutant was observed. Therefore, we conclude that the multiple antibiotic resistance induced by the overexpression of RobA largely depends on the activation of the AcrAB efflux, as well as the activation of micF.

DOI： 10.1111/j.1348-0421.1997.tb01913.x

Scopus

Effects of coronavirus disease 2019 on the spread of respiratory-transmitted human-to-human bacteria Reviewed Open Access

Kajihara T, Yahara K, Kamigaki T, Hirabayashi A, Hosaka Y, Kitamura N, Shimbashi R, Suzuki M, Sugai M, Shibayama K

Journal of Infection Vol. 89 ( 2 ) 2024.8

ect Hirabayashi A, Yahara K, Oka K, Kajihara T, Ohkura T, Hosaka Y, Shibayama K, Sugai M, Yagi T. Comparison of disease and economic burden between MRSA infection and MRSA colonization in a university hospital: a retrospective data integration study. Reviewed Open Access

Hirabayashi A, Yahara K, Oka K, Kajihara T, Ohkura T, Hosaka Y, Shibayama K, Sugai M, Yagi T.

Antimicrob Resist Infect Control Vol. 13 ( 1 ) 2024.2

Protocol for detecting Helicobacter suis infection in gastric biopsies and serum by PCR and ELISA International journal Open Access

Hidenori Matsui, Masato Suzuki, Sae Aoki, Keigo Shibayama, Kengo Tokunaga, Hidekazu Suzuki, Katsuhiro Mabe, Tsuyoshi Kenri, Emiko Rimbara

STAR Protocols Vol. 4 ( 4 ) page： 102556 - 102556 2023.12

Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier BV

Infection with Helicobacter suis, which causes many cases of gastric disease, is not reliably diagnosed. Here, we present a protocol for detecting H. suis infection. We describe steps for collecting gastric biopsies and sera from patients, preparing DNA for PCR, and targeting the H. suis-specific gene. We then define procedures for inoculating biopsies onto primary agar plates and transferring colonies to secondary agar plates. Finally, we detail whole-genome sequencing of bacteria and assess H. suis infection in sera with ELISA. For complete details on the use and execution of these protocols, please refer to Matsui et al.1.

DOI： 10.1016/j.xpro.2023.102556

【上部消化管疾患の残された課題】NHPHによる胃疾患の疫学と病態

徳永健吾, 井田陽介, 三好佐和子, 大野亜希子, 久松理一, 林原絵美子, 松井英則, 鈴木仁人, 柴山恵吾, 大崎敬子

Progress in Medicine Vol. 43 ( 9 ) page： 813 - 815 2023.9

Temporal shifts in the predominant carbapenemase gene types among carbapenemase-producing Klebsiella pneumoniae isolated in Bangkok, Thailand, during 2013–2016 International journal

Noriko Sakamoto, Warawut Laolerd, Yukihiro Akeda, Yo Sugawara, Daisuke Motooka, Norihisa Yamamoto, Dan Takeuchi, Rathina Kumar Shanmugakani, Isao Nishi, Masato Suzuki, Keigo Shibayama, Tetsuya Iida, Pitak Santanirand, Kazunori Tomono, Shigeyuki Hamada

Journal of Medical Microbiology Vol. 72 ( 6 ) 2023.6

Language：English Publishing type：Research paper (scientific journal) Publisher：Microbiology Society

Introduction. Carbapenemase-producing Enterobacteriaceae (CPE) have emerged as a global threat to public health and clinical practice.

Hypothesis/Gap Statement. In Thailand, reports describing CPEs carrying blaNDM and blaOXA-48-like genes have been increasing recently; however, data on detailed plasmid analysis and temporal shift of sequence type and carbapenemase type are limited.

Aim. In this study, we analysed whole-genome sequencing (WGS) data of clinically isolated carbapenemase-producing Klebsiella pneumoniae (CPKP) to reveal the molecular epidemiology of CPKP in a tertiary-care hospital in Bangkok, Thailand.

Methodology. Seventy-seven non-duplicated CPKP isolates collected during 2013–2016 were examined for their drug-resistance genes, sequence types and phylogenetic relationships.

Results. All the tested isolates possessed carbapenemase gene(s), and the major type of carbapenemase gene in 2014–2015 was blaNDM-1, whereas isolates in 2016 harboured more blaOXA-232 than blaNDM-1. Other carbapenemase gene variants, such as blaNDM-4, blaNDM-5, blaOXA-48, blaOXA-181 and blaIMP-14 were detected in some CPKP isolates. Furthermore, this study revealed that CPKP co-harbouring two genes, blaNDM-1 and blaOXA-232 or blaOXA-181, emerged during this period. Notably, such isolates co-carrying the two carbapenemase genes emerged in three different sequence types, even in a single hospital, and then spread clonally. The WGS of CPKP revealed a temporal shift of the predominant carbapenemase genes from blaNDM-1 to blaOXA-232 along with a variation in other carbapenemase gene types within a span of 4 years.

Conclusion. Our findings suggest that a substantial change in CPE types occurred in Thailand and potentially in Southeast Asian countries.

DOI： 10.1099/jmm.0.001711

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Papers - SHIBAYAMA Keigo