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Makoto Shoda - One of the best experts on this subject based on the ideXlab platform.

  • Solid state fermentation of Lipopeptide Antibiotic iturin A by using a novel solid state fermentation reactor system.
    Journal of environmental sciences (China), 2009
    Co-Authors: Takashi Ano, Guang Yuan Jin, Shinji Mizumoto, Mohammad Shahedur Rahman, Kasumasa Okuno, Makoto Shoda
    Abstract:

    A new solid state fermentation reactor (SSFR) for solid substrate was used for the production of Lipopeptide Antibiotic iturin A using Bacillus subtilis RB14-CS. Solid state fermentation (SSF) is the technique of cultivation of microorganisms on solid and moist substrates in the absence of free water. SSF has shown much promise in the development of several bioprocesses and products because of their several advantages like absence of free water that allows simplified downstream processing and low cost. SSFR allows agitation of the SSF culture with improved temperature control and air supply. Interestingly, when okara, the widely available waste product from the tofu industries, was used as the solid substrate for the SSFR, no iturin A production was observed. However, without agitation, production of iturin A was observed in the SSFR but the production level remained low. The low production of iturin A was found to be due to the heat generation and excess temperature rise inside the reactor system during the fermentation process. Maintaining the temperature within a range of 25-30°C, production of iturin A was significantly improved in the SSFR. This was comparable to the laboratory scale production, and signifies the potential application of the SSFR for SSF.

  • production of Lipopeptide Antibiotic iturin a using soybean curd residue cultivated with bacillus subtilis in solid state fermentation
    Applied Microbiology and Biotechnology, 2006
    Co-Authors: Shinji Mizumoto, M Hirai, Makoto Shoda
    Abstract:

    Bacillus subtilis RB14-CS, which suppresses the growth of various plant pathogens in vitro by producing the Lipopeptide Antibiotic iturin A, was cultured using soybean curd residue, okara, a by-product of tofu manufacture in solid-state fermentation. After 4 days incubation, iturin A production reached 3,300 mg/kg wet solid material (14 g/kg dry solid material), which is approximately tenfold higher than that in submerged fermentation. When the okara product cultured with RB14-CS was introduced into soil infested with Rhizoctonia solani, which is a causal agent of damping-off of tomato, the disease occurrence was significantly suppressed. After 14 days, the number of RB14-CS cells remained in soil at the initial level, whereas almost no iturin A was detected in soil. As the okara cultured with RB14-CS exhibited functions of both plant disease suppression and nutritional effect on tomato seedlings, this product is expected to contribute to the recycling of the soybean curd residue.

  • use of soybean curd residue okara for the solid state substrate in the production of a Lipopeptide Antibiotic iturin a by bacillus subtilis nb22
    Process Biochemistry, 1996
    Co-Authors: Akihiro Ohno, Takashi Ano, Makoto Shoda
    Abstract:

    Abstract The possibility of the utilization of soybean curd residue, okara, for the production of a Lipopeptide Antibiotic, iturin A, in solid state fermentation (SSF) by Bacillus subtilis NB22 was investigated. Okara is a by-product of the tofu manufacturing process, now treated as an industrial waste and disposed of mostly by incineration. Dehydrated okara, with improved transportability and preservability, could be used as effectively as the fresh, intact okara for SSF by B. subtilis NB22 for the production of iturin A.

  • production of a Lipopeptide Antibiotic surfactin by recombinant bacillus subtilis in solid state fermentation
    Biotechnology and Bioengineering, 1995
    Co-Authors: Akihiro Ohno, Makoto Shoda
    Abstract:

    Abstract Production of a Lipopeptide Antibiotic, surfactin, in solid state fermentation (SSF) on soybean curd residue, Okara, as a solid substrate was carried out using Bacillus subtilis MI113 with a recombinant plasmid pC112, which contains lpa-14, a gene related to surfactin production cloned at our laboratory from a wild-type surfactin producer, B. subtilis RB14. The optimal moisture content and temperature for the production of surfactin were 82% and 37 degrees C, respectively. The amount of surfactin produced by MI113 (pC112) was as high as 2.0 g/kg wet weight, which was eight times as high as that of the original B. subtilis RB14 at the optimal temperature for surfactin production, 30 degrees C. Although the stability of the plasmid showed a similar pattern in both SSF and submerged fermentation (SMF), production of surfactin in SSF was 4-5 times more efficient than in SMF. (c) 1995 John Wiley & Sons, Inc.

  • production of a Lipopeptide Antibiotic surfactin with recombinant bacillus subtilis
    Biotechnology Letters, 1992
    Co-Authors: Akihiro Ohno, Takashi Ano, Makoto Shoda
    Abstract:

    Production of a Lipopeptide Antibiotic surfactin was carried out using a recombinantBacillus subtilis. Surfactin yield of the recombinant strain was about one and half times as much as that ofBacillus subtilis RB 14, the strain in which the surfactin gene was originated. This system is especially noteworthy because a recombinant strain surpassed the original strain in the production of a bacterial Antibiotic as a secondary metabolite of the bacterium.

Takashi Ano - One of the best experts on this subject based on the ideXlab platform.

  • Improvement of production of Lipopeptide Antibiotic iturin A using fish protein.
    Journal of environmental sciences (China), 2013
    Co-Authors: Umme Salma Zohora, Mohammad Shahedur Rahman, Abdul Wahab Khan, Masahiro Okanami, Takashi Ano
    Abstract:

    To enhance the production of Lipopeptide Antibiotic iturin A, nutrient contents of the culture mediums were investigated in both submerged and biofilm fermentations. As a carbon source maltose and as nitrogen source, fish protein was used. In submerged fermentation maltose uptake was found lower (12%) compared to biofilm fermentation (15%) that was associated with higher cellular growth in biofilm. However, requirement of nitrogen (fish protein) concentration was found similar in both submerged and biofilm fermentations. Production of iturin A in submerged fermentation with 12% maltose and 5% fish protein was 4450 mg/L, and in biofilm fermentation it was 5050 mg/L when 15% maltose and 5% fish protein was used.

  • Solid state fermentation of Lipopeptide Antibiotic iturin A by using a novel solid state fermentation reactor system.
    Journal of environmental sciences (China), 2009
    Co-Authors: Takashi Ano, Guang Yuan Jin, Shinji Mizumoto, Mohammad Shahedur Rahman, Kasumasa Okuno, Makoto Shoda
    Abstract:

    A new solid state fermentation reactor (SSFR) for solid substrate was used for the production of Lipopeptide Antibiotic iturin A using Bacillus subtilis RB14-CS. Solid state fermentation (SSF) is the technique of cultivation of microorganisms on solid and moist substrates in the absence of free water. SSF has shown much promise in the development of several bioprocesses and products because of their several advantages like absence of free water that allows simplified downstream processing and low cost. SSFR allows agitation of the SSF culture with improved temperature control and air supply. Interestingly, when okara, the widely available waste product from the tofu industries, was used as the solid substrate for the SSFR, no iturin A production was observed. However, without agitation, production of iturin A was observed in the SSFR but the production level remained low. The low production of iturin A was found to be due to the heat generation and excess temperature rise inside the reactor system during the fermentation process. Maintaining the temperature within a range of 25-30°C, production of iturin A was significantly improved in the SSFR. This was comparable to the laboratory scale production, and signifies the potential application of the SSFR for SSF.

  • Biofilm formation and Lipopeptide Antibiotic iturin A production in different peptone media.
    Journal of environmental sciences (China), 2009
    Co-Authors: Umme Salma Zohora, Mohammad Shahedur Rahman, Takashi Ano
    Abstract:

    Biofilm fermentation is a newly developed promising technique in fermentation technology. In this study no.3 and no.3S media have been used for the Lipopeptide Antibiotic iturin A production by Bacillus subtilis RB14. The main component of no.3 and no.3S media is Polypepton and Polypepton S, respectively. B. subtilis RB14 produces thick stable biofilm and high amount of iturin A in no.3S medium. Whereas, impaired biofilm formation and lower iturin A production was observed in no.3 medium. From the analytical information it was observed that the amounts of metal ions, such as K(+), Ca(2+) and Mn(2+), cysteine and cellulose are lower in Polypepton compared to the Polypepton S. To investigate their effect on biofilm formation and iturin A production cysteine, cellulose, K(+), Ca(2+) and Mn(2+) were added respectively into the no.3 medium at similar amount that Polypepton S contains. It was observed that individual addition of K(+), Ca(2+), cysteine and cellulose had no effect on biofilm formation, cellular growth induction or iturin A production. However, when Mn(2+) was supplemented in no.3 medium, biofilm development was restored with an improved production of iturin A. Finally, combined addition of investigated substances into the no.3 medium resulted with highly folded, thick biofilm with high cellular growth and iturin A production compared to the original no.3 medium.

  • use of soybean curd residue okara for the solid state substrate in the production of a Lipopeptide Antibiotic iturin a by bacillus subtilis nb22
    Process Biochemistry, 1996
    Co-Authors: Akihiro Ohno, Takashi Ano, Makoto Shoda
    Abstract:

    Abstract The possibility of the utilization of soybean curd residue, okara, for the production of a Lipopeptide Antibiotic, iturin A, in solid state fermentation (SSF) by Bacillus subtilis NB22 was investigated. Okara is a by-product of the tofu manufacturing process, now treated as an industrial waste and disposed of mostly by incineration. Dehydrated okara, with improved transportability and preservability, could be used as effectively as the fresh, intact okara for SSF by B. subtilis NB22 for the production of iturin A.

  • production of a Lipopeptide Antibiotic surfactin with recombinant bacillus subtilis
    Biotechnology Letters, 1992
    Co-Authors: Akihiro Ohno, Takashi Ano, Makoto Shoda
    Abstract:

    Production of a Lipopeptide Antibiotic surfactin was carried out using a recombinantBacillus subtilis. Surfactin yield of the recombinant strain was about one and half times as much as that ofBacillus subtilis RB 14, the strain in which the surfactin gene was originated. This system is especially noteworthy because a recombinant strain surpassed the original strain in the production of a bacterial Antibiotic as a secondary metabolite of the bacterium.

Ahmed E Yousef - One of the best experts on this subject based on the ideXlab platform.

  • biosynthesis of the new broad spectrum Lipopeptide Antibiotic paenibacterin in paenibacillus thiaminolyticus osy se
    Research in Microbiology, 2014
    Co-Authors: En Huang, Yaoqi Guo, Ahmed E Yousef
    Abstract:

    Paenibacterin is a novel Lipopeptide Antibiotic with potent activity against Gram-negative and Gram-positive human pathogens. The Antibiotic consists of a cyclic 13-residue peptide and an N-terminal C₁₅ fatty acyl chain. To elucidate the biosynthesis of paenibacterin, we determined the whole genome sequence of the producer strain Paenibacillus thiaminolyticus OSY-SE, and the function of the peptide synthetase was confirmed experimentally. The gene cluster of paenibacterin was identified within a 52-kb DNA region, encoding thee non-ribosomal peptide synthetases, PbtA, PbtB and PbtC, and two ABC-transporters, PbtD and PbtE. Both PbtA and PbtB consist of five modules, whereas PbtC comprises three modules. Each of these 13 modules consists of three essential domains (condensation-adenylation-thiolation) and assembles an amino acid into the paenibacterin peptide. Selected adenylation domains in the NRPS were cloned and expressed in Escherichia coli; the substrate specificity of each recombinant A-domain was studied in vitro by protein function analysis. The presence of four epimerization domains in paenibacterin peptide synthetases suggests that Orn₁, Orn₄, Lys₇ and Ser₈ in the paenibacterin molecule have d-configuration; the absolute configuration of two ornithine residues in paenibacterin was confirmed by chiral amino acid analysis using Marfey's reagents. Taken together, the findings enabled us to propose the biosynthetic pathway of paenibacterin.

  • draft genome sequence of paenibacillus sp strain osy se a bacterium producing the novel broad spectrum Lipopeptide Antibiotic paenibacterin
    Journal of Bacteriology, 2012
    Co-Authors: En Huang, Yaoqi Guo, Ahmed E Yousef
    Abstract:

    A strain of Paenibacillus sp., OSY-SE, was isolated from soil and found to produce a novel Lipopeptide Antibiotic. The Antibiotic, paenibacterin, is active against Gram-negative and Gram-positive bacterial pathogens. Paenibacterin is biosynthesized by a nonribosomal peptide synthetase pathway. Here we report the draft genome sequence of Paenibacillus sp. OSY-SE.

  • isolation of a paenibacillus sp strain and structural elucidation of its broad spectrum Lipopeptide Antibiotic
    Applied and Environmental Microbiology, 2012
    Co-Authors: En Huang, Chunhua Yuan, Liwen Zhang, Ahmed E Yousef
    Abstract:

    ABSTRACT This research was initiated to search for novel antimicrobial compounds produced by food or environmental microorganisms. A new bacterial strain, designated OSY-SE, which produces a unique and potent antimicrobial agent was isolated from soil. The isolate was identified as a Paenibacillus sp. through cultural, biochemical, and genetic analyses. An antimicrobial compound was extracted from Paenibacillus OSY-SE with acetonitrile and purified using liquid chromatography. After analyses by mass spectrometry (MS) and nuclear magnetic resonance (NMR), the antimicrobial compound was determined to be a cyclic Lipopeptide consisting of a C 15 fatty acyl (FA) chain and 13 amino acids. The deduced sequence is FA-Orn-Val-Thr-Orn-Ser-Val-Lys-Ser-Ile-Pro-Val-Lys-Ile. The carboxyl-terminal Ile is connected to Thr by ester linkage. The new compound, designated paenibacterin, showed antagonistic activities against most Gram-positive and Gram-negative bacteria tested, including Listeria monocytogenes, methicillin-resistant Staphylococcus aureus, Escherichia coli O157:H7, and Salmonella enterica serovar Typhimurium. Paenibacterin is resistant to trypsin, lipase, α-glucosidase, and lysozyme. Its antimicrobial activity was lost after digestion by pronase and polymyxin acylase. Paenibacterin is readily soluble in water and fairly stable to exposure to heat and a wide range of pH values. The new isolate and its antimicrobial agent are being investigated for usefulness in food and medical applications.

Jared Silverman - One of the best experts on this subject based on the ideXlab platform.

  • mutual inhibition through hybrid oligomer formation of daptomycin and the semisynthetic Lipopeptide Antibiotic cb 182 462
    Biochimica et Biophysica Acta, 2013
    Co-Authors: Tianhua Zhang, Jared Silverman, Jawad Kadhum Muraih, Scott D Taylor, Evan Mintzer, Nasim Tishbi, Celine Desert, Michael Palmer
    Abstract:

    Daptomycin is a clinically important Lipopeptide Antibiotic that kills Gram-positive bacteria through membrane depolarization. Its activity requires calcium and the presence of phosphatidylglycerol in the target membrane. Calcium and phosphatidylglycerol also promote the formation of daptomycin oligomers, which have been assumed but not proven to be required for the bactericidal effect. Daptomycin shares substantial structural similarity with another Lipopeptide Antibiotic, A54145; the two have identical amino acid residues in 5 out of 13 positions and similar ones in 4 more positions. We here examined whether these conserved residues are sufficient for oligomer formation. To this end, we used fluorescence energy transfer and excimer fluorescence to detect hybrid oligomers of daptomycin and CB-182,462, a semisynthetic derivative of A54145. Mixtures of the two compounds indeed produced hybrid oligomers, but at the same time displayed a significantly less than additive antibacterial activity against Bacillus subtilis. The existence of functionally impaired oligomers indicates that oligomer formation is indeed important for antibacterial function. However, it also shows that oligomerization is not sufficient; once formed, the oligomers must take another step in order to acquire antibacterial activity. Thus, the amino acid residues shared between daptomycin and CB-182,462 suffice for formation of the oligomer, but not for its subsequent activation.

  • in vitro and in vivo characterization of cb 183 315 a novel Lipopeptide Antibiotic for treatment of clostridium difficile
    Antimicrobial Agents and Chemotherapy, 2012
    Co-Authors: Carmela Mascio, Lawrence I Mortin, Karen T Howland, Andrew Van Praagh, Shuxin Zhang, Anu Arya, Cun Lan Chuong, Chunfeng Kang, Tongchuan Li, Jared Silverman
    Abstract:

    CB-183,315 is a novel Lipopeptide Antibiotic structurally related to daptomycin currently in phase 3 clinical development for Clostridium difficile-associated diarrhea (CDAD). We report here the in vitro mechanism of action, spontaneous resistance incidence, resistance by serial passage, time-kill kinetics, postAntibiotic effect, and efficacy of CB-183,315 in a hamster model of lethal infection. In vitro data showed that CB-183,315 dissipated the membrane potential of Staphylococcus aureus without inducing changes in membrane permeability to small molecules. The rate of spontaneous resistance to CB-183,315 at 8× the MIC was below the limit of detection in C. difficile. Under selective pressure by serial passage with CB-183,315 against C. difficile, the susceptibility of the bacteria changed no more than 2-fold during 15 days of serial passages. At 16× the MIC, CB-183,315 produced a ≥3-log reduction of C. difficile in the time-kill assay. The postAntibiotic effect of CB-183,315 at 8× the MIC was 0.9 h. At 80× the MIC the postAntibiotic effect was more than 6 h. In the hamster model of CDAD, CB-183,315 and vancomycin both demonstrated potent efficacy in resolving initial disease onset, even at very low doses. After the conclusion of dosing, CB-183,315 and vancomycin showed a similar dose- and time-dependent pattern with respect to rates of CDAD recurrence.

  • genetic changes that correlate with reduced susceptibility to daptomycin in staphylococcus aureus
    Antimicrobial Agents and Chemotherapy, 2006
    Co-Authors: Lisa Friedman, Jeff Alder, Jared Silverman
    Abstract:

    Daptomycin is a Lipopeptide Antibiotic with potent activity against gram-positive bacteria. Complete-genome comparisons of laboratory-derived Staphylococcus aureus with decreased susceptibility to daptomycin and their susceptible parent were used to identify genes that contribute to reduced susceptibility to daptomycin. Selective pressure of growth in sublethal concentrations of daptomycin resulted in the accumulation of mutations over time correlating with incremental decreases in susceptibility. Single point mutations resulting in amino acid substitutions occurred in three distinct proteins: MprF, a lysylphosphatidylglycerol synthetase; YycG, a histidine kinase; and RpoB and RpoC, the β and β′ subunits of RNA polymerase. Sequence analysis of mprF, yycF, yycG, rpoB, and rpoC in clinical isolates that showed treatment-emergent increases in daptomycin MICs revealed point mutations in mprF and a nucleotide insertion in yycG, suggesting a role for these genes in decreased susceptibility to daptomycin in the hospital setting.

  • Correlation of Daptomycin Bactericidal Activity and Membrane Depolarization in Staphylococcus aureus
    Antimicrobial agents and chemotherapy, 2003
    Co-Authors: Jared Silverman, Nancy G Perlmutter, Howard M Shapiro
    Abstract:

    The objective of this study was to further elucidate the role of membrane potential in the mechanism of action of daptomycin, a novel Lipopeptide Antibiotic. Membrane depolarization was measured by both fluorimetric and flow cytometric assays. Adding daptomycin (5 micro g/ml) to Staphylococcus aureus gradually dissipated membrane potential. In both assays, cell viability was reduced by >99% and membrane potential was reduced by >90% within 30 min of adding daptomycin. Cell viability decreased in parallel with changes in membrane potential, demonstrating a temporal correlation between bactericidal activity and membrane depolarization. Decreases in viability and potential also showed a dose-dependent correlation. Depolarization is indicative of ion movement across the cytoplasmic membrane. Fluorescent probes were used to demonstrate Ca(2+)-dependent, daptomycin-triggered potassium release from S. aureus. Potassium release was also correlated with bactericidal activity. This study demonstrates a clear correlation between dissipation of membrane potential and the bactericidal activity of daptomycin. A multistep model for daptomycin's mechanism of action is proposed.

Akihiro Ohno - One of the best experts on this subject based on the ideXlab platform.