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STEFANIA STEFANELLI, FEDERICA SPONGA, PIETRO FERRARI, CRISTINA SOTTANI ...
1996 Volume 49 Issue 7 Pages
611-616
Published: July 25, 1996
Released on J-STAGE: November 21, 2006
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During the course of a screening program for inhibitors of
myo-inositol monophosphatase we fermented the strain ATCC 20928, a known producer of L-671, 776. We now show that this strain produces a complex of at least three sesquiterpenic compounds, L-671, 776 (termed factor B) and two structurally related substances, termed factors A and C. Both factors A and C, like L-671, 776, exhibited inhibitory activity against
myo-inositol monophosphatase. Six other fungi producing the above mentioned compounds were also isolated and taxonomically characterized.
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I. Taxonomy, Fermentation, Isolation, Physico-chemical Properties and Biological Activities
TATSUO TANIMOTO, KAORI ONODERA, TSUYOSHI HOSOYA, YASUYUKI TAKAMATSU, T ...
1996 Volume 49 Issue 7 Pages
617-623
Published: July 25, 1996
Released on J-STAGE: November 21, 2006
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In the process of screening for squalene synthase inhibitors from microbial fermentation products we have isolated a novel compound, named schizostatin (Fig. 1), from the culture broth of the mushroom,
Schizophyllum commune SANK 17785. Schizostatin inhibited rat liver microsomal squalene synthase dose dependently and the IC
50 value was 0.84μM. The inhibition was competitive with respect to farnesylpyrophosphate with a
Ki value of 0.45 μM.
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II. Structure Elucidation and Total Synthesis
HIROSHI KOGEN, KEIKO TAGO, SATORU KANEKO, KIYOSHI HAMANO, KAORI ONODER ...
1996 Volume 49 Issue 7 Pages
624-630
Published: July 25, 1996
Released on J-STAGE: November 21, 2006
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Schizostatin (
1) has been isolated as a potent and selective inhibitor of squalene synthase. Its structure has been determined using spectroscopic methods: the compound is shown to be a diterpenoid which has a
trans-dicarboxylic acid moiety. Total synthesis of Schizostatin (
1) was achieved by the highly regio- and stereo selective coupling reaction of an allylic bromide with a barium reagent. The Z-isomer
16 was also prepared using the stereo selective syn-addition of an organocopper reagent to acetylenedicarboxylate.
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I. Taxonomy, Fermentation, Isolation and Biological Activities
MASAHIKO HAYASHI, YONG-PIL KIM, SATOSHI TAKAMATSU, SRISOMPORN PREEPRAM ...
1996 Volume 49 Issue 7 Pages
631-634
Published: July 25, 1996
Released on J-STAGE: November 21, 2006
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Selective growth inhibition against IL-6 dependent cells was detected in fermentation extracts of a fungal strain FO-4649 which was characterized as
Sporothrix species. An active metabolite (1) termed chlovalicin was isolated together with ovalicin and two other ovalicin derivatives (compounds 3 and 4). Chlovalicin, a ovalicin derivative with a chlorinated methylene moiety at the C-1 position of the cyclohexane ring, dose-dependently inhibited the growth of IL-6 dependent MH60 cells (IC50, 7.5μM) in the presence of 0.2U/ml IL-6 and, to a lesser extent, the growth of B16 melanoma cells (IC
50, 38μM). Among the other three compounds, only ovalicin showed inhibitory activity (IC
50, 27μM) against MH60 cells. These four compounds did not show any antimicrobial activity at a concentration of 1000 μg/ml.
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II. Physicochemical Properties and Structural Elucidation
SATOSHI TAKAMATSU, YONG-PIL KIM, TAKAMARO KOMIYA, TOSHIAKI SUNAZUKA, M ...
1996 Volume 49 Issue 7 Pages
635-638
Published: July 25, 1996
Released on J-STAGE: November 21, 2006
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A new growth inhibitor of IL-6 responsive MH60 cells, chlovalicin (MW; 332, C
16H
25O
5Cl), was found in cultures of
Sporothrix sp. FO-4649, together with a known sesquiterpene, ovalicin. The structure of chlovalicin was elucidated by spectroscopic methods. Chlovalicin possesses a chlorinated methylene moiety at the C-1 position, and it corresponds to halogenated products derived from the epoxide ring attached to the C-1 position of ovalicin. The absolute configuration of chlovalicin was clarified as IS, 2R, 35, I'S, 2'R by chemical transformation from ovalicin.
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I. Fermentation, Isolation, and Biological Properties
MASASHI UEKI, KEIICHI ABE, MUHAMMAD HANAFI, KOZO SHIBATA, TOSHIO TANAK ...
1996 Volume 49 Issue 7 Pages
639-643
Published: July 25, 1996
Released on J-STAGE: November 21, 2006
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Novel antifungal antibiotics, UK-2A, B and a mixture of C and D, were obtained from the mycehal cake of
Streptomyces sp. 517-02. All of the UK-2 compounds were similar in structure to antimycin A. The antifungal activities of UK-2 compunds were as strong as that of antimycin A. However, the UK-2 compounds demonstrated weak cytotoxicity compared to antimycin A.
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CLAUDIO QUARTA, ANGELO BORGHI, LUIGI FRANCO ZERILLI, MARIA TERESA DE P ...
1996 Volume 49 Issue 7 Pages
644-650
Published: July 25, 1996
Released on J-STAGE: November 21, 2006
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A new teicoplanin-like antibiotic was discovered when using
Actinoplanes teichomyceticus strain 3/W, the fermentation medium containing Alburex, and the fermentation time 275 hours. The new product was separated from teicoplanin complex by polyamide resin chromatography and purified by Amberlite XAD-7 and affinity resin chromatographies. The structure was established on the basis of the physico-chemical characteristics of the complex and of its aglycone. The new structure is that of teicoplanin with a carbonyl group substituting for the CHNH
2 group of amino acid 1.
We hypothesize that the novel complex is a transformation product of teicoplanin due to a simple transamination reaction, as supported by its structure and by the concomitant decrease in teicoplanin concentration during its production.
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II. Structure Determination
NAOTO KAWAMURA, RYUICHI SAWA, YOSHIKAZU TAKAHASHI, KUNIO ISSHIKI, TSUT ...
1996 Volume 49 Issue 7 Pages
651-656
Published: July 25, 1996
Released on J-STAGE: November 21, 2006
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Novel antibiotics, pyralomicins 1a-1d, 2a-2c were isolated from the culture broth of
Microtetraspora spiralis MI178-34F18. The structures of pyralomicins were determined by various NMR spectral analyses including
1H-
15N HMBC and
13C(
1H) NOE difference experiments.
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III. Biosynthesis of Pyralomicin 1a
NAOTO KAWAMURA, RYUICHI SAWA, YOSHIKAZU TAKAHASHI, TSUTOMU SAWA, HIROS ...
1996 Volume 49 Issue 7 Pages
657-660
Published: July 25, 1996
Released on J-STAGE: November 21, 2006
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The biosynthesis of pyralomicin la (1) was studied by feeding of
13C and
15N labeled compounds to the culture of
Microtetraspora spiralis MI178-34F18. The result indicated that the benzopyranopyrrole unit of 1 was derived from two units of acetate, one unit of propionate and one unit of proline, and that the cyclitol unit of 1 was derived from glucose metabolites. And 4'-O-CH
3 was derived from the S-CH
3 group of methionine.
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KLAUS GOEKE, ANNE DREPPER, HERMANN PAPE
1996 Volume 49 Issue 7 Pages
661-663
Published: July 25, 1996
Released on J-STAGE: November 21, 2006
JOURNAL
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The α-glucosidase inhibitor acarbose is modified during incubation with cell-free extract from the producing
Actinoplanes strain. The formation of this product depends on the presence of ATP. Chromatographic and chemical properties of the purified transformation product indicate the presence of a phosphate ester. The structure is deduced by NMR analysis and shown to be acarbose7-phosphate.
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ANNE DREPPER, HERMANN PAPE
1996 Volume 49 Issue 7 Pages
664-668
Published: July 25, 1996
Released on J-STAGE: November 21, 2006
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A phosphotransferase which modifies the α-glucosidase inhibitor acarbose by phosphorylation at its 7-position was isolated from the acarbose producer
Actinoplanes sp. and purified to homogeneity. The sequence of the first 20 amino acids of the enzyme was determined. The enzyme is an ATP-dependent kinase and shows high specificity for acarbose and some related compounds containing the pseudodisaccharide moiety (acarviosin). The product formed by the enzyme, acarbose-7-phosphate, shows a significant lower inhibitory activity towards disaccharidases than acarbose itself. The acarbose producing organism contains a maltase which is inhibited by acarbose, but to a much lesser extent by acarbose-7-phosphate. The possible role of acarbose 7-phosphotransferase as part of a self-defense mechanism against acarbose in the producing organism is discussed.
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OSAMU JOHDO, TAKEO YOSHIOKA, HIROSHI NAGANAWA, TOMIO TAKEUCHI, AKIHIRO ...
1996 Volume 49 Issue 7 Pages
669-675
Published: July 25, 1996
Released on J-STAGE: November 21, 2006
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Microbial conversion of β-rhodomycinone and aklavinone using an aclarubicin-negative
Streptomyces galilaeus mutant afforded new anthracycline antibiotics CG21-C and CG1-C which had a rednosyl-2-deoxyfucosyl-rhodosaminyl trisaccharide residue at C-7 of each added aglycone. They were produced only when a prolonged conversion culture took place. Because the usual conversion products containing a cinerulosyl-2-deoxyfucosyl-rhodosaminyl residue were at first accumulated and then decreased during further cultivation, it was evident that they occurred by the modification of terminal cinerulose. The isolation, purification, and structural determination are described, and cytotoxicity
in vitro against cultured L1210 cells and the formation mechanism are discussed.
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KAZUTOH TAKESAKO, SHIGETOSHI MIZUTANI, HITOSHI SAKAKIBARA, MASAHIRO EN ...
1996 Volume 49 Issue 7 Pages
676-681
Published: July 25, 1996
Released on J-STAGE: November 21, 2006
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The antifungal antibiotic aureobasidin A (AbA) is a cyclic depsipeptide composed of eight amino acids and a hydroxy acid. New Ab analogs were produced by feeding various amino acids to
Aureobasidium pullulans R106 c-712 in a chemically-defined medium containing glucose and ammonium sulfate. The constituent amino acids of AbA at positions 3 (L-phenylalanine), 4 (N-methyl-L-phenylalanine), 5 (L-proline), 6 (L-
allo-isoleucine) and 8 (L-leucine) were replaced by respective analogous amino acids such as ofluoro-L-phenylalanine, 4-hydroxy-L-proline, L-norleucine and L-norvaline, resulting in the production of eight new Ab analogs. This is the first paper to describe amino acid replacements at positions 3, 5 and 8. L-[l-
13C]-Valine exogenously added was incorporated into the three valine-related moieties of AbA at positions 2, 7 (both
N-methyl-L-valine) and 9 (β-hydroxy-N-methyl-L-valine), but these moieties were never replaced by exogenous amino acid analogs. The comparative antifungal activities of AbA and the eight new Ab analogs were determined.
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KUNIMOTO HOTTA, TETSU OGATA, JUN ISHIKAWA, MASANORI OKANISHI, SATOSHI ...
1996 Volume 49 Issue 7 Pages
682-688
Published: July 25, 1996
Released on J-STAGE: November 21, 2006
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The biochemical basis for the multiple resistance to aminoglycoside antibiotics (AGs) of kasugamycin-producing
Streptomyces kasugaensis MB273 was studied. The strain was resistant to a wide range of deoxystreptamine (DOS)-containing AGs as well as astromicin (ASTM) group antibiotics. These AGs strongly inhibited
in vitro polyU-directed polyphenylalanine-synthesis using ribosomes from the strain, while they were acetylated and inactivated by the MB273 cell free extract supplemented with acetyl-CoA. It seemed thus likely that the acetyltransferase activity played a critical role for the multiple AG resistance. The acetylation was selective to AGs with 2'-NH
2, suggesting the involvement of aminoglycoside 2'-
N-acetyltransferase, A AC (2'). Interestingly, the acetylation of istamycin B (ISM-B; an ASTM group AG) resulted in the formation of two different products (1-N-acetyl ISM-B and 2"-N-acetyl ISM-B) at a similar ratio. In this context, an AAC (2') gene cloned as an ISM-B resistance gene from the strain MB273 directed the conversion of ISM-B to only 1-N-acetyl ISM-B. It seemed likely that two types of AACs [AAC(2') and a novel one] were involved in the mechanism of resistance to ASTM group AGs.
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XUE-LONG SUN, HIROAKI TAKAYANAGI, KEIICHI MATSUZAKI, HARUO TANAKA, KIM ...
1996 Volume 49 Issue 7 Pages
689-692
Published: July 25, 1996
Released on J-STAGE: November 21, 2006
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Several isochromophilone analogues were synthesized from sclerotiorin (
1) by Wittig reactions and aldol condensation reaction. The structures of the products were elucidated from MS, elemental analysis,
1H NMR and
13C NMR spectra, and their inhibitory activities against gp!20-CD4 binding were determined.
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JULIE C. LEE, STEPHEN J. COVAL, JON CLARDY
1996 Volume 49 Issue 7 Pages
693-696
Published: July 25, 1996
Released on J-STAGE: November 21, 2006
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KEN-ICHI KIMURA, HIDETOSHI TAKAHASHI, NOBUO MIYATA, MAKOTO YOSHIHAMA, ...
1996 Volume 49 Issue 7 Pages
697-699
Published: July 25, 1996
Released on J-STAGE: November 21, 2006
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ROSARIO CRUZ, M. SELMA ARIAS, M. ENRIQUETA ARIAS, JUAN SOLIVERI
1996 Volume 49 Issue 7 Pages
700-702
Published: July 25, 1996
Released on J-STAGE: November 21, 2006
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NYUNT PHAY, HIROSHI YADA, TAKAKO HIGASHIYAMA, ATSUSHI YOKOTA, AKITAMI ...
1996 Volume 49 Issue 7 Pages
703-705
Published: July 25, 1996
Released on J-STAGE: November 21, 2006
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I. Taxonomy and Production
NAOTO KAWAMURA, NAOKO KINOSHITA, RYUICHI SAWA, YOSHIKAZU TAKAHASHI, TS ...
1996 Volume 49 Issue 7 Pages
706-709
Published: July 25, 1996
Released on J-STAGE: November 21, 2006
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PASCALE VINCENDON, EMILIANA CORTI, AMBROGINA GUINDANI, CRISTINA BRUNAT ...
1996 Volume 49 Issue 7 Pages
710-712
Published: July 25, 1996
Released on J-STAGE: November 21, 2006
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KUNIAKI TATSUTA, SHOHEI YASUDA
1996 Volume 49 Issue 7 Pages
713-715
Published: July 25, 1996
Released on J-STAGE: November 21, 2006
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