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SACHIKO TAKAISHI, NAOKO TUCHIYA, AIYA SATO, TERUAKI NEGISHI, YASUYUKI ...
1998 Volume 51 Issue 9 Pages
805-815
Published: September 25, 1998
Released on J-STAGE: January 27, 2009
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A novel endothelin-converting enzyme (ECE) inhibitor, B-90063, was isolated from the culture supernatant of the newly discovered marine bacterium
Blastobacter sp. SANK 71894. Based on spectral analyses and chemical reactions, the structure of B-90063 was determined to be bis[6-formyl-4-hydroxy-2-(2′-
n-pentyloxazol-4′-yl)-4-pyridon-3-yl]-disulfide (
1a). Human and rat ECEs were inhibited more potently by B-90063, with respective IC
50 values of 1.0 and 3.2 μM, than were other neutral endopeptidases such as NEP and type-I and -IV collagenases. B-90063 also inhibited the binding of ET-1 to rat ET
A and bovine ET
B receptors, though its antagonistic activities were weak. B-90063, thus, may abolish the physiological actions of endothelins through the ECE inhibitory and receptor antagonistic mechanisms.
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New Antibiotics from a Mycena Species
MICHAEL DAFERNER, TIMM ANKE, VERONIKA HELLWIG, WOLFGANG STEGLICH, OLOV ...
1998 Volume 51 Issue 9 Pages
816-822
Published: September 25, 1998
Released on J-STAGE: January 27, 2009
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The antifungal and cytostatic compound strobilurin M (
1) is a new variant of the strobilurins produced by
Mycena sp. 96097, a tropical basidiomycete. The same fungus was found to produce tetrachloropyrocatechol (
3a) and tetrachloropyrocatechol methyl ether (
3b), new natural products, which exhibit antifungal, antibacterial and cytotoxic activities.
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I. Taxonomy, Fermentation, Isolation, Physico-chemical Properties and Structure Elucidation
MASARU UYEDA, KAZUMI YOKOMIZO, YOSHIAKI MIYAMOTO, EL-SAYED E. HABIB
1998 Volume 51 Issue 9 Pages
823-828
Published: September 25, 1998
Released on J-STAGE: January 27, 2009
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A novel antiherpetic agent, fattiviracin A1, was isolated from the culture broth of strain No. 2445 identified as
Streptomyces microflavus. It was purified through 1-butanol extraction, column chromatographies on Diaion HP-10 and silica gel and HPLC using a reverse phase column. The structure of fattiviracin A1 was determined by several spectroscopic experiments and chemical degradations. It is a new macrocyclic diester consisting of four D-glucose units and two (C
24 and C
33) hydroxy fatty acids. It is closely related to cycloviracins B
1 and B
2, but differs from these known compounds in both the length of its side chain and the sugar moiety.
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J. M. SIGMUND, C. F. HIRSCH
1998 Volume 51 Issue 9 Pages
829-836
Published: September 25, 1998
Released on J-STAGE: January 27, 2009
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The antifungal antibiotic rustmicin was detected in the fermentation broth of the actinomycete MA 7094 as a specific inhibitor of sphingolipid biosynthesis in
Candida albicans and as a potent fungicidal agent against
Cryptococcus neoformans. Taxonomic characterization by both classical means and PCR fingerprinting supported the assignment of the producing culture to the genus
Micromonospora. Fermentation medium optimization studies showed that the concentration of tomato paste in the medium was critical to increased production of rustmicin by MA 7094. The stimulatory effect of tomato paste in the medium on rustmicin production appeared to be related to the maintenance of pH at or below a value of 6.0. Addition of the antifoam agent P-2000 to the fermentation was found to dramatically reduce the rustmicin titer, while substitution of another antifoam agent, UCON-LB625, resulted in a 100% increase in the amount of rustmicin detected. After fermentation optimization studies and the generation of a non-sporulating mutant of MA 7094, the rustmicin titer was increased from an initial titer of 10 mg/liter to 145 mg/liter.
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GUY H. HARRIS, ALI SHAFIEE, M. ANGELES CABELLO, JAMES E. CUROTTO, OLGA ...
1998 Volume 51 Issue 9 Pages
837-844
Published: September 25, 1998
Released on J-STAGE: January 27, 2009
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The mode of action of the known antifungal macrolides rustmicin (
1) and galbonolide B (
2) has been determined to be the inhibition of sphingolipid biosynthesis. A large scale fermentation and isolation process was developed for production of large quantities of rustmicin. New 21-hydroxy derivatives of both compounds were isolated from pilot scale fermentations and were also produced by biotransformation of rustmicin and galbonolide B.
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Biological Origins and Semisynthesis of Thionaphthomycins, and the Structures of Naphthomycins I and J
ANTONY M. HOOPER, RODNEY W. RICKARDS
1998 Volume 51 Issue 9 Pages
845-851
Published: September 25, 1998
Released on J-STAGE: January 27, 2009
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Fermentations of
Streptomyces sp. E/784 produce low levels of the novel C-30 alkylthio-substituted ansamycin antibiotics naphthomycins J (
9) and I (
10), in addition to the more abundant C-30 hydroxylated analogues actamycin (
1) and naphthomycin D (
2) and C-30 chlorinated analogues naphthomycins H (
3) and A (
4). The addition of
N-acetyl-L-cysteine to the fermentation medium substantially increases the production of the thionaphthomycins J and I at the expense of their chloro analogues H and A. Other thiols and thiol progenitors are similarly utilised, including
N-acetyl-L-cysteine methyl ester which affords the known naphthomycin F (
8) and its novel 2-demethyl homologue (
7). The formation of thioansamycins from chloroansamycins and thiols
in vivo is probably non-enzymic since similar conversions can be effected
in vitro.
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XU PING, YUKIHIRO AKEDA, KEN-ICHI FUJITA, TOSHIO TANAKA, MAKOTO TANIGU ...
1998 Volume 51 Issue 9 Pages
852-856
Published: September 25, 1998
Released on J-STAGE: January 27, 2009
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The mechanism of the antifungal action of AKD-2C was studied by using
Torulaspora delbrueckii IFO 1621 as a model. AKD-2C slightly inhibited the incorporation of radioactive precursors into protein, RNA and lipid, but not into DNA. On the other hand, AKD-2C greatly enhanced the leakage of K
+ ions from treated cells and showed a potent effect on liposomal glucose leakage. Using electron microscopic studies, though drastic morphological changes were not observed, an increase in cell membrane irregularities and swelling of the mitochondria caused by AKD-2C were demonstrated. These results suggest that the antifungal action of AKD-2C is due to effects on the yeast cell membrane.
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PAUL M. HERSHBERGER, A. GREG SWITZER, KENNETH E. YELM, MILT C. COLEMAN ...
1998 Volume 51 Issue 9 Pages
857-871
Published: September 25, 1998
Released on J-STAGE: January 27, 2009
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This reports the synthesis and
in vitro antimicrobial properties of a series of 2-thioether-linked quinolonyl-carbapenems. Although the title compounds exhibited broad spectrum activity, the MICs were generally higher than those observed for selected benchmark carbapenems, quinolonyl-penems, and quinolones. Enzyme assays suggested that the title compounds are potent inhibitors of penicillin binding proteins and inefficient inhibitors of bacterial DNA-gyrase. Uptake studies indicated that the new compounds are not substrates for the
norA encoded quinolone efflux pump.
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GIANBATTISTA PANZONE, PIETRO FERRARI, MICHAEL KURZ, ALDO TRANI
1998 Volume 51 Issue 9 Pages
872-879
Published: September 25, 1998
Released on J-STAGE: January 27, 2009
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The structure of a product, isolated during the synthesis of the semisynthetic glycopeptide MDL 63, 246, was elucidated on the basis of spectroscopic methods and proved to be a novel glycopeptide containing a 3-oxazolin-5-one ring between positions 36 and 38. Subjected to acid hydrolysis this compound gave the corresponding pseudo aglycone and aglycone derivatives which maintained the original oxazolinone structure. Tested for antibacterial activity, these compounds showed a moderate activity against Gram-positive and inactive against Gram-negative bacteria.
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TOSHIHIRO KUNIGAMI, KAZUO SHIN-YA, KAZUO FURIHATA, KEIKO FURIHATA, YOI ...
1998 Volume 51 Issue 9 Pages
880-882
Published: September 25, 1998
Released on J-STAGE: January 27, 2009
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IV. Antifungal Action of Methyl UK-1
MASASHI UEKI, KOZO SHIBATA, MAKOTO TANIGUCHI
1998 Volume 51 Issue 9 Pages
883-885
Published: September 25, 1998
Released on J-STAGE: January 27, 2009
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Application of the Yeast Two-hybrid System
KATSUHIDE IGARASHI, KEIKO SHIGETA, SHINKICHI KOHNO, TOSHIO ISOHARA, TO ...
1998 Volume 51 Issue 9 Pages
886-888
Published: September 25, 1998
Released on J-STAGE: January 27, 2009
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MASAKI SHIMIZU, TOMOKO NONOMIYA, FRITZ SHIGENOBU, KOJI O'HARA, TETSUO ...
1998 Volume 51 Issue 9 Pages
889-892
Published: September 25, 1998
Released on J-STAGE: January 27, 2009
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GORJANA LAZAREVSKI, GABRIJELA KOBREHEL, AMALIJA NARANDA, ZRINKA BANIC- ...
1998 Volume 51 Issue 9 Pages
893-896
Published: September 25, 1998
Released on J-STAGE: January 27, 2009
JOURNAL
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