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Kazunobu Matsushita – One of the best experts on this subject based on the ideXlab platform.
Role of a membrane-bound aldehyde dehydrogenase complex AldFGH in acetic acid fermentation with Acetobacter pasteurianus SKU1108.Applied microbiology and biotechnology, 2018Co-Authors: Toshiharu Yakushi, Gunjana Theeragool, Minenosuke Matsutani, Seiya Fukunari, Tomohiro Kodama, Shun Nina, Naoya Kataoka, Kazunobu MatsushitaAbstract:
Acetic acid fermentation is widely considered a consequence of ethanol oxidation by two membrane-bound enzymes—alcohol dehydrogenase and aldehyde dehydrogenase (ALDH)—of acetic acid bacteria. Here, we used a markerless gene disruption method to construct a mutant of the Acetobacter pasteurianus strain SKU1108 with a deletion in the aldH gene, which encodes the large catalytic subunit of a heterotrimeric ALDH complex (AldFGH), to examine the role of AldFGH in acetic acid fermentation. The ΔaldH strain grew less on ethanol-containing medium, i.e., acetic acid fermentation conditions, than the wild-type strain and significantly accumulated acetaldehyde in the culture medium. Unexpectedly, acetaldehyde oxidase activity levels of the intact ΔaldH cells and the ΔaldH cell membranes were similar to those of the wild-type strain, which might be attributed to an additional ALDH isozyme (AldSLC). The apparent KM values of the wild-type and ΔaldH membranes for acetaldehyde were similar to each other, when the cells were cultured in nonfermentation conditions, where ΔaldH cells grow as well as the wild-type cells. However, the membranes of the wild-type cells grown under fermentation conditions showed a 10-fold lower apparent KM value than those of the cells grown under nonfermentation conditions. Under fermentation conditions, transcriptional levels of a gene for AldSLC were 10-fold lower than those under nonfermentation conditions, whereas aldH transcript levels were not dramatically changed under the two conditions. We suggest that A. pasteurianus SKU1108 has two ALDHs, and the AldFGH complex is indispensable for acetic acid fermentation and is the major enzyme under fermentation conditions.
Complete Genome Sequencing and Comparative Genomic Analysis of the Thermotolerant Acetic Acid Bacterium, Acetobacter pasteurianus SKU1108, Provide a New Insight into ThermotoleranceMicrobes and environments, 2016Co-Authors: Minenosuke Matsutani, Gunjana Theeragool, Toshiharu Yakushi, Hideki Hirakawa, Eri Hiraoka, Kazunobu MatsushitaAbstract:
Acetobacter pasteurianus SKU1108 is a typical thermotolerant acetic acid bacterium. In this study, the complete genome sequence of the SKU1108 strain was elucidated, and information on genomic modifications due to the thermal adaptation of SKU1108 was updated. In order to obtain a clearer understanding of the genetic background responsible for thermotolerance, the SKU1108 genome was compared with those of two closely related complete genome strains, thermotolerant A. pasteurianus 386B and mesophilic A. pasteurianus NBRC 3283. All 24 “thermotolerant genes” required for growth at higher temperatures in the thermotolerant Acetobacter tropicalis SKU1100 strain were conserved in all three strains. However, these thermotolerant genes accumulated amino acid mutations. Some biased mutations, particularly those that occurred in xanthine dehydrogenase XdhA, may be related to thermotolerance. By aligning whole genome sequences, we identified ten SKU1108 strain-specific regions, three of which were conserved in the genomes of the two thermotolerant A. pasteurianus strains. One of the regions contained a unique paralog of the thermotolerant gene xdhA, which may also be responsible for conferring thermotolerance. Thus, comparative genomics of complete genome sequences may provide novel insights into the phenotypes of these thermotolerant strains.
Influence of Acetobacter pasteurianus SKU1108 aspS gene expression on Escherichia coli morphologyJournal of microbiology (Seoul Korea), 2013Co-Authors: Kannipa Tasanapak, Kazunobu Matsushita, Uraiwan Masud-tippayasak, Wichien Yongmanitchai, Gunjana TheeragoolAbstract:
The aspS gene encoding Aspartyl-tRNA synthetase (AspRS) from a thermotolerant acetic acid bacterium, Acetobacter pasteurianus SKU1108, has been cloned and characterized. The open reading frame (ORF) of the aspS gene consists of 1,788 bp, encoding 595 amino acid residues. The highly conserved Gly-Val-Asp-Arg ATP binding motif (motif 3) is located at the position 537–540 in the C-terminus. Deletion analysis of the aspS gene upstream region suggested that the promoter is around 173 bp upstream from the ATG initiation codon. Interestingly, transformation with the plasmids pGEM-T138, pUC138, and pCM138 synthesizing 138 amino acid C-terminal fragments of AspRS, that carry the ATP binding domain, caused E. coli cell lengthening at 37 and 42°C. Moreover, E. coli harboring pUC595 (synthesizing all 595 amino acids) and a disordered aspS gene in pGEM-T138 had normal rod shapes. The normal rod shape was observed in E. coli harboring pD539V following site-directed mutagenesis of the ATP binding domain. We propose that over-production of truncated C-terminal peptides of AspRS may cause sequestration of intracellular ATP in E. coli, leaving less ATP for cell division or shaping cell morphology.
Min Wang – One of the best experts on this subject based on the ideXlab platform.
Two-stage oxygen supply strategy based on energy metabolism analysis for improving acetic acid production by Acetobacter pasteurianus.Journal of industrial microbiology & biotechnology, 2018Co-Authors: Yu Zheng, Renkuan Zhang, Yangang Chang, Jia Song, Liu Jing, Min WangAbstract:
Oxygen acts as the electron acceptor to oxidize ethanol by acetic acid bacteria during acetic acid fermentation. In this study, the energy release rate from ethanol and glucose under different aerate rate were compared, and the relationship between energy metabolism and acetic acid fermentation was analyzed. The results imply that proper oxygen supply can maintain the reasonable energy metabolism and cell tolerance to improve the acetic acid fermentation. Further, the transcriptions of genes that involve in the ethanol oxidation, TCA cycle, ATP synthesis and tolerance protein expression were analyzed to outline the effect of oxygen supply on cell metabolism of Acetobacter pasteurianus. Under the direction of energy metabolism framework a rational two-stage oxygen supply strategy was established to release the power consumption and substrates volatilization during acetic acid fermentation. As a result, the acetic acid production rate of 1.86 g/L/h was obtained, which were 20.78% higher than that of 0.1 vvm one-stage aerate rate. And the final acetic acid concentration and the stoichiometric yield were 88.5 g/L and 94.1%, respectively, which were 84.6 g/L and 89.5% for 0.15 vvm one-stage aerate rate.
Improving the acetic acid tolerance and fermentation of Acetobacter pasteurianus by nucleotide excision repair protein UvrAApplied microbiology and biotechnology, 2018Co-Authors: Yu Zheng, Xiaolei Bai, Yangang Chang, Jia Song, Jing Wang, Jun Mou, Min WangAbstract:
Acetic acid bacteria (AAB) are widely used in acetic acid fermentation due to their remarkable ability to oxidize ethanol and high tolerance against acetic acid. In Acetobacter pasteurianus, nucleotide excision repair protein UvrA was up-regulated 2.1 times by acetic acid when compared with that without acetic acid. To study the effects of UvrA on A. pasteurianus acetic acid tolerance, uvrA knockout strain AC2005-ΔuvrA, uvrA overexpression strain AC2005 (pMV24-uvrA), and the control strain AC2005 (pMV24), were constructed. One percent initial acetic acid was almost lethal to AC2005-ΔuvrA. However, the biomass of the UvrA overexpression strain was higher than that of the control under acetic acid concentrations. After 6% acetic acid shock for 20 and 40 min, the survival ratios of AC2005 (pMV24-uvrA) were 2 and 0.12%, respectively; however, they were 1.5 and 0.06% for the control strain AC2005 (pMV24). UvrA overexpression enhanced the acetification rate by 21.7% when compared with the control. The enzymes involved in ethanol oxidation and acetic acid tolerance were up-regulated during acetic acid fermentation due to the overexpression of UvrA. Therefore, in A. pasteurianus, UvrA could be induced by acetic acid and is related with the acetic acid tolerance by protecting the genome against acetic acid to ensure the protein expression and metabolism.
Impacts of bioprocess engineering on product formation by Acetobacter pasteurianusApplied microbiology and biotechnology, 2018Co-Authors: Yu Zheng, Yangang Chang, Sankuan Xie, Jia Song, Min WangAbstract:
Aerobic Acetobacter pasteurianus is one of the most widely used bacterial species for acetic acid and vinegar production. The acetic acid condition is the primary challenge to the industrial application of A. pasteurianus. Thus, numerous endeavors, including strain improvement and process control, have been performed to improve the product formation and acetic acid tolerance of A. pasteurianus. The metabolic features of A. pasteurianus have been gradually elucidated through omic techniques, such as genomics and proteomics. In this mini review, we summarized bioprocess engineering methods that improved product formation of A. pasteurianus by exploiting its metabolic features. Moreover, given that A. pasteurianus is an important functional microorganism in traditional vinegar production, we discuss its metabolism when cocultured with other microorganisms in traditional vinegar production.
Jan Turna – One of the best experts on this subject based on the ideXlab platform.
Transformation of microorganisms with the plasmid vector with the replicon from pAC1 from Acetobacter pasteurianus.Biochemical and biophysical research communications, 1995Co-Authors: Jozef Grones, Jan TurnaAbstract:
A number of gram-negative and gram-positive bacteria species was screened for the expression of the gram-negative plasmid pACK5 and pACT72 with replicon of pAC1 plasmid from Acetobacter pasteurianus. As was described previously, both plasmids were expressed in Escherichia coli, Acetobacter pasteurianus, Acetobacter aceti, Shigella spp. and Citrobacter spp. Expressions of plasmids were successful in twelve species tested, Comamonas terrigena, Salmonella typhimurium, Serratia marcescens, Bacillus cereus, Bacillus megatericum, Bacillus subtilis, Lactobacillus helveticus, Micrococcus luteus, Sarcina lutea, Staphylococcus aureus, Staphylococcus epidermidis, Streptoccocus feacalis, and the stability of plasmid DNA was tested after cultivation in non-selective conditions.
Some properties of restriction endonuclease ApaBI from Acetobacter pasteurianusBiochimica et biophysica acta, 1993Co-Authors: Jozef Grones, Jan TurnaAbstract:
Abstract A new site-specific endonuclease has been isolated from Acetobacter pasteurianus and has been named Apa BI. The enzyme recognizes 35 cleavage sites on bacteriophage lambda DNA, 20 sites on adenovirus-2 DNA and 2 sites on plasmid pBR322. The recognition sequence for this enzyme is 3′-CGT/NNNNNACG-5′ 5′-GCANNNNN/TGC-3′.
Characterization of the Replicon from Plasmid pAC1 from Acetobacter pasteurianusBiochemical and biophysical research communications, 1993Co-Authors: Jozef Grones, A. Kralova, Jan TurnaAbstract:
A panel of recombinant plasmids pACK5 and pACT7 was prepared by introducing kanamycin and tetracycline resistance into the partially split plasmid pAC1 which contained replicon isolated from Acetobacter pasteurianus. The replicon in plasmid pAC1 is compatible with the ColE1 replicon. Compared to pBR322, the plasmid had more than 30 copies per chromosome in Escherichia coli cells. Plasmids were transformed into E. coli DH1, Acetobacter pasteurianus 3614, Acetobacter aceti 3620, Shigella, Citrobacter, and Brevibacterium flavum cells, and the stability of plasmid DNA was tested after cultivation in nonselective conditions.