• Microbiology and Biotechnology Letters
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• v.23 no.2
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• pp.123-130
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• 1995

DNA topoisomerase I have been shown to be important therapeutic target in cancer chemotherapy. Chemotaxonomy and numerical identification were carried out for an isolate strain No.7489 producing an antibiotic that inhibits DNA topoisomerase I activity. The genus of strain No.7489 was determined as Streptomyces sp. from culture, morphological and chemotaxonomic data. Thirty-nine taxonomic unit characters were tested and the data were analyzed numerically using the TAXON program. The isolate was best matched to Streptomyces melanosporofaciens in the major cluster 32 of Streptomyces. Therefore, it was concluded that the isolate was identified to be a member of Streptomyces melanosporofaciens.

• Journal of Integrative Natural Science
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• v.1 no.1
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• pp.47-53
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• 2008

In a previous study, we showed that Cecropin A (1-8)-Magainin 2 (1-12) hybrid peptide (CA-MA)'s analogue, Anal P5, exhibit broad-spectrum antimicrobial activity. Anal P5, designed by flexible region (positions 9, 10)-substitution, Lys- (positions 4, 8, 14, 15) and Leu- (positions 5, 6, 12, 13, 16, 17, 20) substitutions, showed an enhanced antimicrobial and antitumor activity without hemolysis. The primary objective of the present study was to gain insight into the relevant mechanisms of antimicrobial activities of Anal P5 by using flow cytometric analysis. Anal P5 exhibits strong antifungal activity in a salt concentration independent manner. In addition, Anal P5 causes significant morphological alterations of the bacterial surfaces as shown by scanning electron microscopy, supporting its antibacterial activity. Its potent antibiotic activity suggests that Anal P5 is an excellent candidate as a lead compound for the development of novel antibiotic agents.

• Archives of Pharmacal Research
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• v.26 no.6
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• pp.446-448
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• 2003

Cystocin belongs to the class of nucleoside antibiotics from Streptomyces sp. GCA0001. Cystocin showed good activity against Gram-positive bacteria, but showed less activity against the Gram-negative bacteria. Cystocin exhibited about two to four folds higher activity than puromycin. Especially, cystocin shows relatively strong activity against Streptococcus strains. Cystocin shows quite potent antitumor activity against all of the cells tested showing $IC_{50}$ values of 0.10 to 0.14 $\mu$ g/mL. This in vitro result indicates that the cytotoxocity of cystocin is two ten folds more active than puromycin s.

• Korean Journal of Pharmacognosy
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• v.19 no.3
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• pp.153-169
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• 1988

The combined use of the J-modulated selective INEPT and CSCM 1DNMR techniques is described for the structure elucidation of several new classes of compound including prionitin, the loureirins and larreantin, and for the regiosubstitution of the furanonaphthoquinones. Spectroscopic studies on the conformation of the cytotoxic agent savinin are also described, together with the NMR assignments and preliminary biosynthetic experiments on the antitumor antibiotic staurosporine.

• Microbiology and Biotechnology Letters
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• v.27 no.6
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• pp.440-445
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• 1999

In order to investigate structure-antibiotic activity relationships of brevinin-1 and thanatin containing Rana box composed of basic loop formed by disulfide bridge in their arboxy terminus, thanatin, brevinin 1 and their analogues (T-B1, T-B2 and B-T) in which their Rana box sequence exchanged was designed and synthesized by the solid phase method using Fmoc-chemistry. The basic sequence of Rana box of thanatin had more significant effect on both antibacterial and antifungal activity than that of brevinin 1. The tail sequence (QRM) of thanatin was found to be important in its antibacterial and antifungal activity. Rana box sequence of brevinin-1 did not have a significant effect on its antitumor and phospholipid vesicle-aggregating activities. Brevinin-1 showed stronger $\alpha$-helical structure in the membrane-mimicking environment such as SDS micelle than thanatin. A remarkable increase in a-helicity of bervinin-1 plays more important role in antibiotic activity than that of thanatin. Furthermore, antibacterial activity of thanatin against E. coli resulted from the disruptive effect against the outer cell membrane of E. coli.

• Environmental Mutagens and Carcinogens
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• v.18 no.2
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• pp.98-103
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• 1998

Epigallocatechin gallate (EGCG) was reported to exert weak cytotoxicity against normal healthy cells such as C3H10T1/2 cells, but profound inhibitory effects on the initiation or promotion stage of chemical carcinogenesis in mammary gland, blood and mouse skin. This study was carried out to develop antitumor agents with weak side effects and strong antitumor activity. Human skin melanoma cells (HBT 69) and human oral epitheloid carcinoma cells (OCL 17) were cultured in RPMI-1640 media containing 10% fetal bovine serum, antibiotic, and fungizone. After incubation for 24 hrs, the cells were treated with various amounts of (EGCG) for 48 hrs. The growth inhibitory effects of EGCG in human oral epitheloid carcinoma cells were evaluated by the 3- (4,5-djmethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT), neutral red (NR), and sulforhodamine B protein (SRB) assays of colorimetric methods. The light microscopic study was also carried out to observe morphological changes of the treated cells. These results obtained were as follows; 1. Significantly inhibitory effects of EGCG against cultured human oral epithelioid carcinoma cells. 2. Significantly inhibitory effects against cultured human skin melanoma cells treated with 50 $\mu$M EGCG, but decreased inhibitory effects in 100 $\mu$M EGCG. 3. Degenerative changes against cultured human oral epitheloid carcinoma cells. 4. Degenerative changes against human skin melanoma cells treated with 50 UM EGCG, but recovered degenerative changes in 100 $\mu$M EGCG.

• Biomolecules & Therapeutics
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• v.5 no.2
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• pp.215-221
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• 1997

In an effort to screen new selective antitumor agents from the broth of soil microorganism, cytotoxicity oriented screening was performed against tumor cells and 3 compounds (Compound 1, 2 and 3) were isolated from Sreptomyces parvullus ISP 5048 and their chemical structures were determined. Among these compounds, Compound 2 showed the highest cytotoxicity against P388Dl and L1210. While the $IC_{50}$/ values of compound 2 against P388Dl and L1210 were 0.073$\mu$g/ml and 0.07$\mu$g/ml, respectively, and the $IC_{50}$/ value of Compound 3 was 0.17$\mu$g/ml against human lung cancer cells, A549, the cytotoxicity of Compound 2 and 3 against normal cell line, Vero E6 cell was about 4- and 8-fold lower than that of adriamycin. Based on the chemical analysis data, Compound 3 was octacosamicine A, a known antibiotic, which was reported by Dobasih et al. (1988). Taken together the results demonstrated that Compound 2 and Compound 3 has the possibility to be developed as antitumor agent because of its potent cytotoxicity as well as high selectivity against various cancer cell lines.

• Archives of Pharmacal Research
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• v.21 no.4
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• pp.385-390
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• 1998

Adozelesin and carzelesin are synthetic analogues of the extremely potent antitumor antibiotic CC-1065, which alkylates N3 of adenine in a consensus sequence $5^1$-(A/T)(A/T)$A^*$ ($A^*$ is the site of alkylation). We have investigated the DNA sequence selectivity of adozelesin and carzelesin by thermally ind ced DNA strand cleavage assay using radiolabeled restriction DNA fragments. An analysis of alkylation patterns shows that the consensus sequences for carzelesin and adozelesin have been found to be $5^1$-(A/T)(A/T)$A^*$ and $5^1$-(A/F)(G/C)(A/T)$A^*$. A new consensus sequence, $5^1$-(A/T)(A/T)$CA^*$, has been observed to display an additional alkylation site for adozelesin but not for carzelesin. These results indicate that the pattern of sequence selectivity induced by carzelesin is similar but not identical to those induced by adozelosin.

• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.3
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• pp.263-269
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• 1990

Aqueous solution pigment produced by Steptomyces californicus KS-89 showed a vivid bluish purple pigment and purified by silica gel column chromatography. The pigment indicated a deep purple color zone by the C. I. E chromatic diagram and showed UV absorption maxima at 575nm. The color intensity in aqueous solution was fairly stable in the ranges of pH5-8 and was not affected by UV light however sometimes it had faded slightly by the heat. It was possible to prevent significantly by the addition of metal salt. Especially this pigment has no mutagenicity and antitumor activity and it appears to be devoid of antibiotic activity.

• Korean Journal of Veterinary Research
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• v.34 no.1
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• pp.165-172
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• 1994

DA-125 is a new anthracycline antitumor antibiotic, which is derived from adriamycin. The potential of DA-125 to induce embryotoxicity was evaluated in the Sprague-Dawley rats. One hundred twenty naturally mated SD rats(sperm in vaginal lavage=day 0) were distributed among three treated groups and a control group. DA-125 was administered intravenously at dose levels of 0. 0.1, 0.3 and 1.0mg/ kg/day. Dams were treated from day 7 to 17 of gestation and were subjected to the caesarean section on day 20. At 1 mg/kg, reduced food intake, reduced body weight and decreased weight of spleen were observed in dams. An increase in the resorption rate and a reduction in the fetal weight were also found. In addition, various types of external, visceral and skeletal malformations occurred at an incidence of 11.9, 41.8 and 14.5%, respectively. Characteristic malformations include exencephalia, gastroschisis, cleft lip, dilatation of lateral and 3rd ventricle, fused ribs, among others. There were no signs of maternal toxicity or embryotoxicity at 0.1 and 0.3mg/kg. The results show that the test agent DA-125 is embryotoxic at maternally subtoxic dose in rats.