Naoyuki Fukuchi

Structure of phytotoxin syringomycin produced by a sugar cane isolate of Pseudomonas syringae pv. syringae

Abstract The structure of the phytotoxin syringomycin produced by a sugar cane isolate of Pseudomonas syringae pv. syringae was determined as 1 with NMR and mass spectrometry.

Mikimopine, an opine in hairy roots of tobacco induced byAgrobacterium rhizogenes

Abstract A novel opine, mikimopine, was isolated from hairy roots of tobacco induced by Agrobacterium rhizogenes NIAES1724, and its structure determined as (4 R ,7 S )-4-(2-car☐ylethyl)-4,5,6,7-tetrahydroimidazo[4,5,- c ]pyridine-4,6-dicar☐ylic acid.

Structures of syringostatins A and B, novel phytotoxins produced by pseudomonas syringae pv. syringae isolated from lilac blights

Abstract The structures of syringostatins A and B produced by Pseudomonas syringae pv. syringae SY12 were determined as 1 and 2 , respectively, from NMR and Mass spectrometry.

Isolation and structural elucidation of syringostatins, phytotoxins produced by Pseudomonas syringae pv. syringae lilac isolate

A bacterial strain of Pseudomonas syringae pv. syringae isolated from lilac was found to produce a homologous mixture of phytotoxins different from syringomycin and syringotoxin. The toxins were termed Syringostatins and the structures of the main components, Syringostatins A and B, were determined by 2D-NMR spectroscopy and mass spectrometry. Minor component structures were elucidated from mass/mass spectra.

Macrophage Inhibition of Lymphocyte and Tumor Cell Growth Is Mediated by 25–Hydroxycholesterol in the Cell Membrane

We have previously reported that a lipid molecule in the membrane fraction of cloned macrophage hybridomas inhibited the growth of lymphocytes and several tumor cell lines. In this study, the inhibitory lipid molecule in the membrane fraction of macrophages was analyzed by thin–layer chromatography and identified as 25–hydroxycholesterol, a family of oxysterols. This conclusion was confirmed by analysis using gas chromatography–mass spectrometry. In addition, both 25–hydroxycholesterol and the lipid molecule recovered from macrophage cell membrane induced apoptosis of the murine T cell lymphoma, BW–5147. These results suggest that an oxysterol expressed in the macrophage cell membrane may participate in the regulation of cell growth through cell contact.

A new nucleoside derivative, AJP117510, as an inhibitor of integrin α2β1-collagen binding

A new nucleoside derivative, AJP117510 (1) was isolated from unidentified fungus AJ117510. The structure of 1 was elucidated by spectroscopic analyses. Nucleoside 1 inhibited the binding of integrin α2β1 to collagen in a dose dependent manner with an IC50 value of 5.9 µM.

Structural Elucidation of Rotihibin B by Tandem Mass Spectrometry

Structural Elucidation of Rotihibin B by Tandem Mass Spectrometry Naoyuki Fukuchi, Jiro Nakayama, Seiji Takayama, Akira Isogai & Akinori Suzuki To cite this article: Naoyuki Fukuchi, Jiro Nakayama, Seiji Takayama, Akira Isogai & Akinori Suzuki (1992) Structural Elucidation of Rotihibin B by Tandem Mass Spectrometry, Bioscience, Biotechnology, and Biochemistry, 56:7, 1152-1153, DOI: 10.1271/bbb.56.1152 To link to this article: http://dx.doi.org/10.1271/bbb.56.1152

CONFORMATIONAL ANALYSIS OF MIKIMOPINE

Molecular dynamics calculations were applied to the natural product mikimopine and its lactam. The method described here was found to be efficient for generation and search of low energy conformers. The results obtained are in good agreement with NMR data.