The Experts below are selected from a list of 321 Experts worldwide ranked by ideXlab platform

Hiroshi Habe - One of the best experts on this subject based on the ideXlab platform.

Benjamin Philmus - One of the best experts on this subject based on the ideXlab platform.

  • jizanpeptins cyanobacterial protease inhibitors from a symploca sp cyanobacterium collected in the red sea
    Journal of Natural Products, 2018
    Co-Authors: David Anthony Gallegos, Ryan D Cohen, Alec O Vallotaeastman, Josep Sauri, Thomas R Williamson, Diaa T A Youssef, Lamiaa A Shaala, Patrick Videau, Gary E Martin, Benjamin Philmus
    Abstract:

    Jizanpeptins A–E (1–5) are micropeptin depsipeptides isolated from a Red Sea specimen of a Symploca sp. cyanobacterium. The planar structures of the jizanpeptins were established using NMR spectroscopy and mass spectrometry and contain 3-amino-6-hydroxy-2-piperidone (Ahp) as one of eight residues in a typical micropeptin motif, as well as a side chain terminal Glyceric Acid sulfate moiety. The absolute configurations of the jizanpeptins were assigned using a combination of Marfey’s methodology and chiral-phase HPLC analysis of hydrolysis products compared to commercial and synthesized standards. Jizanpeptins A–E showed specific inhibition of the serine protease trypsin (IC50 = 72 nM to 1 μM) compared to chymotrypsin (IC50 = 1.4 to >10 μM) in vitro and were not overtly cytotoxic to HeLa cervical or NCI-H460 lung cancer cell lines at micromolar concentrations.

  • homotyrosine containing cyanopeptolins 880 and 960 and anabaenopeptins 908 and 915 from planktothrix agardhii cya 126 8
    Journal of Natural Products, 2009
    Co-Authors: Hilary S Okumura, Cyril Portmann, Benjamin Philmus, Thomas Hemscheidt
    Abstract:

    Two homotyrosine-bearing cyanopeptolins are described from Planktothrix agardhii CYA 126/8. The compounds feature a common homotyrosine-containing cyclohexadepsipeptide and differ by sulfation of an exocyclically located 2-O-methyl-d-Glyceric Acid residue. In addition we describe two anabaenopeptins, which contain two homotyrosine residues, one of which is N-methylated. The anabaenopeptins have a common cyclopentapeptide portion and differ in the amino Acid linked to it via an ureido bond, arginine and tyrosine, respectively.

Keiji Sakaki - One of the best experts on this subject based on the ideXlab platform.

  • effect of membrane bound aldehyde dehydrogenase encoding gene disruption on Glyceric Acid production in gluconobacter oxydans
    Journal of Oleo Science, 2014
    Co-Authors: Hiroshi Habe, Tokuma Fukuoka, Dai Kitamoto, Shun Sato, Keiji Sakaki
    Abstract:

    Gluconobacter oxydans IFO12528 is able to produce Glyceric Acid (GA) from glycerol through the action of a membrane-bound alcohol dehydrogenase (mADH), which is required for GA production. To determine whether membrane-bound aldehyde dehydrogenase (mALDH) also plays a role in GA production in G. oxydans, we constructed an aldH-disrupted mutant of G. oxydans (ΔaldH). ΔaldH was unable to produce acetic Acid from ethanol, but was able to produce GA at a level approximately half that of the wildtype strain, suggesting the involvement of another ALDH in GA production. We also investigated the enantiomeric composition of GA produced by the IFO12528 and ΔaldH strains. No difference in GA composition was evident in the ΔaldH mutant, with ~73% D-GA enantiomeric excess observed in both strains.

  • stepwise synthesis of 2 3 o dipalmitoyl d Glyceric Acid and an in vitro evaluation of its cytotoxicity
    Journal of Oleo Science, 2012
    Co-Authors: Shun Sato, Tokuma Fukuoka, Dai Kitamoto, Hiroshi Habe, Keiji Sakaki
    Abstract:

    2,3-O-Dipalmitoyl-D-Glyceric Acid (PA2-DGA) was synthesized from D-Glyceric Acid calcium salt and palmitoyl chloride with improved yield. Direct condensation between the D-Glyceric Acid calcium salt and palmitoyl chloride produced PA2-DGA with a yield of <10%, whereas stepwise synthesis yielded this compound at up to 24% of overall yield. PA2-DGA was then subjected to a cytotoxic test using normal human dermal fibroblasts and primary normal human dermal microvascular endothelial cells. This compound had no toxic effects on human cells in vitro at concentrations up to 34 µM.

  • synthesis of dilinoleoyl d Glyceric Acid and evaluation of its cytotoxicity to human dermal fibroblast and endothelial cells
    Journal of Oleo Science, 2011
    Co-Authors: Shun Sato, Tokuma Fukuoka, Dai Kitamoto, Hiroshi Habe, Keiji Sakaki
    Abstract:

    A novel derivative of Glyceric Acid (GA), dilinoleoyl-D-Glyceric Acid (LA2-DGA), was synthesized from D-GA calcium salt and linoleoyl chloride and evaluated for cytotoxicity. The D-GA calcium salt was first reacted with 4-methoxybezylchloride, and the resulting compound was esterified with linoleoyl chloride. This reaction was followed by hydrolysis of the 4-methoxybenzyl moiety, yielding LA2-DGA. LA2-DGA was then subjected to cytotoxicity testing using normal human dermal fibroblasts and primary normal human dermal microvascular endothelial cells. LA2-DGA showed no significant toxic effects in either type of cell.

  • membrane bound alcohol dehydrogenase is essential for Glyceric Acid production in acetobacter tropicalis
    Journal of Oleo Science, 2011
    Co-Authors: Hiroshi Habe, Tokuma Fukuoka, Dai Kitamoto, Shun Sato, Toshiharu Yakushi, Kazunobu Matsushita, Keiji Sakaki
    Abstract:

    Acetobacter tropicalis NBRC16470 can produce highly enantiomerically pure D-Glyceric Acid (D-GA; >99 % enantiomeric excess) from glycerol. To investigate whether membrane-bound alcohol dehydrogenase (mADH) is involved in GA production in A. tropicalis, we amplified part of the gene encoding mADH subunit I (adhA) using polymerase chain reaction and constructed an adhA-disrupted mutant of A. tropicalis (ΔadhA). Because ΔadhA did not produce GA, we confirmed that mADH is essential for the conversion of glycerol to GA. We also cloned and sequenced the entire region corresponding to adhA and adhB, which encodes mADH subunit II. The sequences showed high identities (84-86 %) with the equivalent mADH subunits from other Acetobacter spp.

  • effect of Glyceric Acid calcium salt on the viability of ethanol dosed gastric cells
    Journal of Oleo Science, 2011
    Co-Authors: Hiroshi Habe, Tokuma Fukuoka, Dai Kitamoto, Shun Sato, Keiji Sakaki
    Abstract:

    D-Glyceric Acid (D-GA) calcium has been reported to accelerate ethanol oxidation in vivo in rats (Eriksson et al., Metabolism, 56, 895-898 (2007)). However, no other reports have shown that D-GA can reduce the harmful effects of ethanol. In this study, the effects of D-, L-, and DL-GA calcium on ethanol-dosed gastric cell viability were investigated using human gastric carcinoma cells (Kato III) and normal rat gastric mucosa cells (RGM1). Addition of 2% and 3 % ethanol to Kato III and RGM1 cells, respectively, decreased their cell viability by approximately 20-50 % after 24 or 72 h of cultivation. In 2 % ethanol-dosed Kato III cells cultivated for 24 h, addition of 0.002-20 µg/mL D- and L-GA calcium did not affect cell viability. Similarly, addition of less than 20 µg/mL DL-GA calcium did not affect cell viability. However, when 20 µg/mL DL-GA calcium was added, cell viability increased by 35.7 % after 72 h of incubation, compared to the viability of control cells without ethanol or GA. Addition of 20 µg/mL DL-GA calcium to 3 % ethanol-dosed RGM1 cells cultivated for 24 or 72 h also increased cell viability up to those observed in control cells. These results suggest that a racemic mixture of GA may have the strongest effect on enhancing the viability of ethanol-exposed cells.

Dai Kitamoto - One of the best experts on this subject based on the ideXlab platform.

Tokuma Fukuoka - One of the best experts on this subject based on the ideXlab platform.

  • microbial resolution of dl Glyceric Acid for l Glyceric Acid production with newly isolated bacterial strains
    Journal of Bioscience and Bioengineering, 2015
    Co-Authors: Shun Sato, Tokuma Fukuoka, Dai Kitamoto, Tomotake Morita, Hiroshi Habe
    Abstract:

    To produce L-Glyceric Acid (L-GA) from DL-GA, microbial resolution was investigated using newly isolated bacterial strains capable of enantiospecific degradation of D-GA. Strains GA3R and GA72P, identified as Serratia and Pseudomonas species, respectively, exhausted D-GA within 72 h, resulting in production of L-GA with enantiomeric purity ≥89%.

  • draft genome sequence of acetobacter tropicalis type strain nbrc16470 a producer of optically pure d Glyceric Acid
    Genome Announcements, 2014
    Co-Authors: Hideaki Koike, Tokuma Fukuoka, Shun Sato, Tomotake Morita, Hiroshi Habe
    Abstract:

    ABSTRACT Here we report the 3.7-Mb draft genome sequence of Acetobacter tropicalis NBRC16470T, which can produce optically pure d-Glyceric Acid (d-GA; 99% enantiomeric excess) from raw glycerol feedstock derived from biodiesel fuel production processes.

  • effect of membrane bound aldehyde dehydrogenase encoding gene disruption on Glyceric Acid production in gluconobacter oxydans
    Journal of Oleo Science, 2014
    Co-Authors: Hiroshi Habe, Tokuma Fukuoka, Dai Kitamoto, Shun Sato, Keiji Sakaki
    Abstract:

    Gluconobacter oxydans IFO12528 is able to produce Glyceric Acid (GA) from glycerol through the action of a membrane-bound alcohol dehydrogenase (mADH), which is required for GA production. To determine whether membrane-bound aldehyde dehydrogenase (mALDH) also plays a role in GA production in G. oxydans, we constructed an aldH-disrupted mutant of G. oxydans (ΔaldH). ΔaldH was unable to produce acetic Acid from ethanol, but was able to produce GA at a level approximately half that of the wildtype strain, suggesting the involvement of another ALDH in GA production. We also investigated the enantiomeric composition of GA produced by the IFO12528 and ΔaldH strains. No difference in GA composition was evident in the ΔaldH mutant, with ~73% D-GA enantiomeric excess observed in both strains.

  • stepwise synthesis of 2 3 o dipalmitoyl d Glyceric Acid and an in vitro evaluation of its cytotoxicity
    Journal of Oleo Science, 2012
    Co-Authors: Shun Sato, Tokuma Fukuoka, Dai Kitamoto, Hiroshi Habe, Keiji Sakaki
    Abstract:

    2,3-O-Dipalmitoyl-D-Glyceric Acid (PA2-DGA) was synthesized from D-Glyceric Acid calcium salt and palmitoyl chloride with improved yield. Direct condensation between the D-Glyceric Acid calcium salt and palmitoyl chloride produced PA2-DGA with a yield of <10%, whereas stepwise synthesis yielded this compound at up to 24% of overall yield. PA2-DGA was then subjected to a cytotoxic test using normal human dermal fibroblasts and primary normal human dermal microvascular endothelial cells. This compound had no toxic effects on human cells in vitro at concentrations up to 34 µM.

  • Bioprocessing of Glycerol into Glyceric Acid for Use in Bioplastic Monomer
    Journal of Oleo Science, 2011
    Co-Authors: Tokuma Fukuoka, Dai Kitamoto, Hiroshi Habe, Kazuhiko Sakaki
    Abstract:

    Utilization of excess glycerol supplies derived from the burgeoning biodiesel industry has recently become very important. Glyceric Acid (GA) is one of the most promising glycerol derivatives, and it is abundantly obtained from glycerol by a bioprocess using acetic Acid bacteria. In this study, a novel branched-type poly(lactic Acid) (PLA) was synthesized by polycondensation of lactide in the presence of GA. The resulting branched PLA had lower crystallinity and glass transition temperatures than the conventional linear PLA, and the peak associated with the melting point of the branched PLA disappeared. Moreover, in a blend of the branched polymer, the crystallization of the linear PLA occurred at a lower temperature. Thus, the branched PLA containing GA synthesized in this study could potentially be used as a novel bio-based modifier for PLA.