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LÁSZLÓ VÉRTESY, HERBERT KOGLER, ASTRID MARKUS, MA ...
2001 Volume 54 Issue 10 Pages
771-782
Published: October 25, 2001
Released on J-STAGE: September 19, 2008
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The terpene peptide memnopeptide A (
1), C
76H
108N
16O
18S, MW 1564, was isolated from a culture of the fungus
Memnoniella echinata FH 2272 on casein peptone. The structure of the novel compound was elucidated with the aid of 2D NMR experiments and from amino acid analysis and mass spectrometric sequencing of the peptide. The compound consists of a known phenylspirodrimane subunit linked to the decapeptide Met-His-Gln-Pro-His-Gln-Pro-Leu-Pro-Pro. This proline-rich peptide is a subsequence of β-casein. From the observed absence in the literature of any other highly significant sequence homologues, memnopeptide A can be assumed to arise from metabolic products of the fungus with direct incorporation of constituents of the nutrient medium. The formation of memnopeptide A suggests this may be a mechanism for storage of amines by the fungus. Memnopeptide A has weak antibacterial activity against Gram-positive bacteria and effects half-maximal activation of sarco(endo)plasmic reticulum Ca
2+ ATPase (SERCA2) at a concentration of 12.5 μm.
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LIN NIE, MASASHI UEKI, HIDEAKI KAKEYA, HIROYUKI OSADA
2001 Volume 54 Issue 10 Pages
783-788
Published: October 25, 2001
Released on J-STAGE: September 19, 2008
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We have developed a novel p21
WAF1 promoter activator screening system based on rapid and facile luciferase activity assay of a model cell system (H1299/tsp53-luc cells), a stable luciferase expression cell line established by transfecting H1299/tsp53 cells with a reporter gene construct pWWP-Luc-BSD. This plasmid was constructed by subcloning the 2.4kb p21
WAF1 promoter and a 2.6kb of luciferase cDNA fragment activated by the p21
WAF1 promoter into a pMAM2-BSD expression vector containing the blasticidin S deaminase gene (BSD). A BSD-resistant clone H1299/tsp53-luc#4, showing the highest response to p53 activation (by temperature shift from 37°C to 32°C) by luciferase production, was used for screening microbial culture broths. Among approximately 1200 screened samples, trichostatin A related compounds and a new compound, lucilactaene, were isolated. This provides an effective and facile screening system for p21
WAF1 promoter activators which should be of considerable value in the rapid identification of new anticancer agents.
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KOHKI ENDO, KEIKO KAMO, KUNIAKI HOSONO, TERUHIKO BEPPU, KENJI UEDA
2001 Volume 54 Issue 10 Pages
789-796
Published: October 25, 2001
Released on J-STAGE: September 19, 2008
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Nitrosoguanidine-induced melanin-negative mutants of
Streptomyces griseus were classified according to their ability to produce streptomycin and A-factor, and to form aerial mycelium. A large proportion of the mutants showed deficiency in either antibiotic production and morphological development or both, suggesting close regulatory correlation between melanogenesis and morphological and physiological differentiation. The tyrosinase-encoding
mel operon of
S. griseus was cloned and examined for its role in melanogenesis of this organism. As in other
Streptomyces homologues, the operon consisted of two open reading frames,
melCl encoding the putative cofactor and
melC2 encoding the tyrosinase. Regardless of the distinct sequence similarity, introduction of the operon on plasmids failed to confer melanin production in the melanin-negative mutants, and the disruption of
melC2 barely affected the melanin productivity, which indicated the presence of another enzyme involved in the melanogenesis in
S. griseus. On the other hand,
mel on a high-copy-number plasmid caused precocious aerial mycelium formation in
Streptomyces lividans TK21 suggesting a stimulatory role of tyrosinase in morphological development.
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MARTIN KRAUSE, ANTJE LINDEMANN, MIRKO GNNSKI, TILL HORNBOGEN, GERHARD ...
2001 Volume 54 Issue 10 Pages
797-804
Published: October 25, 2001
Released on J-STAGE: September 19, 2008
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New cyclohexadepsipeptides of the enniatin type with potential anthelmintic properties were produced by two different strategies: 1.
In vitro synthesis by use of the multienzyme enniatin synthetase, and 2.
in vivo precursor feeding of enniatin producing strains
Fusarium scirpi and
Fusarium sambucinum. The compounds were analyzed by HPLC, various NMR measurements and mass spectrometry. The three
N-methyl L-amino acid positions in the enniatin B molecule could be gradually replaced by other (
N-methyl) L-amino acids,
e.g. alanine, cysteine, threonine and serine. The latter two amino acids yield new enniatins with functional groups in the hydrophobic side chains. Similarly the three D-2-hydroxyisovalerate residues, present in all naturally occuring enniatins, could be substituted by D-2-hydroxybutyric acid and D-lactic acid. Despite its lower yield the
in vitro synthesis has the advantage of a broader variety of products formed.
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KAN FANG, GERHARD SCHLINGMANN, ANNMARIE ENOS, GUY T. CARTER
2001 Volume 54 Issue 10 Pages
805-809
Published: October 25, 2001
Released on J-STAGE: September 19, 2008
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Selected nemadectins (formerly LL-F28249 series
1)) have been fed to a panel of microorganisms with the aim of generating new derivatives. In addition to products resulting from the oxidation of the terminal methyl group (C-29), a unique phosphorylated nemadectin was isolated. The phosphate group was determined to be at C-23 by HMBC between phosphorus and H-23. Milbemycin or nemadectin derivatives with natural substituents involving the 23-hydroxyl group were hitherto unknown.
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TETSUO KISO, YOSHINOSUKE USUKI, XU PING, KEN-ICHI FUJITA, MAKOTO TANIG ...
2001 Volume 54 Issue 10 Pages
810-817
Published: October 25, 2001
Released on J-STAGE: September 19, 2008
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L-2, 5-Dihydrophenylalanine (DHPA), a phenylalanine analogue, induced apoptosis in human promyelocytic leukemia cells (HL-60). This apoptosis was demonstrated by morphological changes of the cells, such as fragmentation of nuclei and chromatin condensation, and by some evidence found in biochemical analysis, such as DNA ladder and activation of caspase 3. The DHPA-induced apoptosis was prevented by a pan-caspase inhibitor, Z-VAD-fmk, and a cysteine protease inhibitor, E-64d, which inhibits calpains and camepsin B and L. A calpain inhibitor, Z-LL-H, did not affect this apoptosis. A cathepsin B specific inhibitor, CA074-Me, prevented only chromatin condensation. However, E-64d and a cathepsin L specific inhibitor, Z-FY(
t-Bu)-dmk, protected the cells from both chromatin condensation and oligonucleosomal DNA fragmentation. As proceeding to the apoptotic process, the activities of both cathepsin B and L increased gradually. These results indicated that DHPA was an inducer of cathepsin-dependent apoptosis in HL-60 cells.
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HARUMI CHIBA, SATOSHI ASANUMA, MEGUMI OKAMOTO, JUNJI INOKOSHI, HARUO T ...
2001 Volume 54 Issue 10 Pages
818-826
Published: October 25, 2001
Released on J-STAGE: September 19, 2008
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The first step in cellular entry of HIV involves binding of the viral envelope glycoprotein complex (gp120/gp41) to specific receptor molecules on the target cells. The cell-cell fusion (syncytium formation) between env expressing cells and CD4+ cells mimics the viral infection of the host cells. To search for anti-HIV substances preventing this process, we constructed the recombinant cell lines, HeLa/CD4/Lac-Z and HeLa/T-env/Tat for T-cell tropic (HIV-1
NL4-3) system, and HOS/CD4/CCR5/Lac-Z and HeLa/M-env/Tat for macrophage tropic (HIV-1
SF162) system. When each pair of cells were co-incubated for 20 hours, the multinuclear giant cells (syncytia) were formed and β-galactosidase was expressed. These systems are less biohazardous because no infectious virus particles are used. Their validity in screening for anti-HIV substances which inhibit syncytium formation was confirmed using various known HIV entry inhibitors.
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II. Chemical Modification and Biological Activity
WON-SUCK SUN, HYO-SUNG LEE, JUNG-MIN PARK, SUNG-HAN KIM, JU-HYUN YU, J ...
2001 Volume 54 Issue 10 Pages
827-830
Published: October 25, 2001
Released on J-STAGE: September 19, 2008
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A series of novel
N-substituted tyramine (2-
p-hydroxyphenylethylamine) derivatives (
1-
11) were synthesized and evaluated for their inhibitory activity against pig kidney aldose reductase (EC 1, 1, 1, 21). Of these compounds,
N-2-
p-hydroxyphenylethyl maleamic acid (
10) exhibits the strongest aldose reductase inhibitory activity, which is 22 times more potent than that of YUA001
1).
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WON-GON KIM, NAN-KYU SONG, ICK-DONG YOO
2001 Volume 54 Issue 10 Pages
831-835
Published: October 25, 2001
Released on J-STAGE: September 19, 2008
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RYUICHIRO NAKAI, SHINGO KAKITA, AKIRA ASAI, SHIGERU CNIBA, SHIRO AKINA ...
2001 Volume 54 Issue 10 Pages
836-839
Published: October 25, 2001
Released on J-STAGE: September 19, 2008
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SANG B. HANR, HO J. LEE, YUNG H. KHO, YOUNG J. JEON, SANG H. LEE, HYUN ...
2001 Volume 54 Issue 10 Pages
840-843
Published: October 25, 2001
Released on J-STAGE: September 19, 2008
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DAVID BARRETT, AKIRA TANAKA, ETSUKO WATABE, KATSUYUKI MAKI, FUMIAKI IK ...
2001 Volume 54 Issue 10 Pages
844-847
Published: October 25, 2001
Released on J-STAGE: September 19, 2008
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K. C. SEKHAR RAO, S. DIVAKAR, N. G. KARANTH, A. P. SATTUR
2001 Volume 54 Issue 10 Pages
848-849
Published: October 25, 2001
Released on J-STAGE: September 19, 2008
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HIDEAKI KAKEYA, SHUN-ICHIRO KAGEYAMA, LIN NIE, RIE ONOSE, GEN OKADA, T ...
2001 Volume 54 Issue 10 Pages
850-854
Published: October 25, 2001
Released on J-STAGE: September 19, 2008
JOURNAL
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