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Saito S, Arai MA. Methodology for awakening the potential secondary metabolic capacity in actinomycetes. Beilstein J Org Chem 2024; 20:753-766. [PMID: 38633912 PMCID: PMC11022428 DOI: 10.3762/bjoc.20.69] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Accepted: 03/27/2024] [Indexed: 04/19/2024] Open
Abstract
Secondary metabolites produced by actinomycete strains undoubtedly have great potential for use in applied research areas such as drug discovery. However, it is becoming difficult to obtain novel compounds because of repeated isolation around the world. Therefore, a new strategy for discovering novel secondary metabolites is needed. Many researchers believe that actinomycetes have as yet unanalyzed secondary metabolic activities, and the associated undiscovered secondary metabolite biosynthesis genes are called "silent" genes. This review outlines several approaches to further activate the metabolic potential of actinomycetes.
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Affiliation(s)
- Shun Saito
- Department of Biosciences and Informatics, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan
| | - Midori A Arai
- Department of Biosciences and Informatics, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan
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Liu C, Zhang Z, Fukaya K, Oku N, Harunari E, Urabe D, Igarashi Y. Isolation and structure determination of allopteridic acids A-C and allokutzmicin from an unexplored actinomycete of the genus Allokutzneria. J Antibiot (Tokyo) 2023; 76:305-315. [PMID: 37059821 DOI: 10.1038/s41429-023-00611-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Revised: 03/05/2023] [Accepted: 03/08/2023] [Indexed: 04/16/2023]
Abstract
Two classes of new polyketides, allopteridic acids A-C (1-3) and allokutzmicin (4), were isolated from the culture extract of an actinomycete of the genus Allokutzneria. The structures of 1-4 were elucidated through the interpretation of NMR and MS analytical data. Compounds 1-3 possess the same carbon skeleton with pteridic acids but their monocyclic core structures are distinct from the spiro-bicyclic acetal structures of pteridic acids. Compound 4 is a linear polyketide of an unprecedented class, featured by a guanidino-terminus and an epoxide modification. Compounds 1-3 promoted the root elongation of germinated lettuce seeds by ca. 10-40% at 1~10 μM whereas 4 retarded the seed growth. Compound 4 exhibited weak antimicrobial activity against Candida albicans with MIC 25 μg mL-1.
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Affiliation(s)
- Chang Liu
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama, 939-0398, Japan
| | - Zhiwei Zhang
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama, 939-0398, Japan
| | - Keisuke Fukaya
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama, 939-0398, Japan
| | - Naoya Oku
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama, 939-0398, Japan
| | - Enjuro Harunari
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama, 939-0398, Japan
| | - Daisuke Urabe
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama, 939-0398, Japan
| | - Yasuhiro Igarashi
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama, 939-0398, Japan.
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Species-specific secondary metabolism by actinomycetes of the genus Phytohabitans and discovery of new pyranonaphthoquinones and isatin derivatives. J Antibiot (Tokyo) 2023; 76:249-259. [PMID: 36864231 DOI: 10.1038/s41429-023-00605-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 02/03/2023] [Accepted: 02/13/2023] [Indexed: 03/04/2023]
Abstract
To further exploit secondary metabolic potential of a minor actinomycete genus Phytohabitans within the family Micromonosporaceae, metabolite profiling by HPLC-UV analysis, combined with 16S rDNA sequence-based phylotyping were attempted on seven Phytohabitans strains available at the public culture collection. The strains were grouped into three clades and each exhibited unique and distinct metabolite profiles, which were highly conserved among strains within the same clade. These results were consistent with previous observations on two other actinomycetes genera, reconfirming species-specificity of secondary metabolite production, which were conventionally thought to be strain-specific. A strain RD003215, belonging to the P. suffuscus clade, produced multiple metabolites, some of which were presumed to be naphthoquinones. Liquid fermentation followed by chromatographic separation of the broth extract led to the discovery of three new pyranonaphthoquinones, designated habipyranoquinones A-C (1-3), and one new isatin derivative, (R)-N-methyl-3-hydroxy-5,6-dimethoxyoxindole (4), along with three known synthetic compounds, 6,8-dihydroxydehydro-α-lapachone (5), N-methyl-5,6-dimethoxyisatin (6), and 5,6-dimethoxyisatin (7). Structures of 1-4 were unequivocally elucidated by NMR, MS, and CD spectral analysis, with assistance of density functional theory-based NMR chemical shift prediction and ECD spectral calculation. Compound 2 displayed antibacterial activity against Kocuria rhizophila and Staphylococcus aureus with MIC 50 µg/mL and cytotoxicity against P388 murine leukemia cells with an IC50 value of 34 µM. Compounds 1 and 4 also showed cytotoxicity against P388 cells with IC50 values of 29 and 14 µM, respectively.
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Lu S, Zhou T, Fukaya K, Harunari E, Oku N, Urabe D, Igarashi Y. Krasilnikolides A and B and Detalosylkrasilnikolide A, Cytotoxic 20-Membered Macrolides from the Genus Krasilnikovia: Assignment of Anomeric Configuration by J-Based Configuration Analysis. JOURNAL OF NATURAL PRODUCTS 2022; 85:2796-2803. [PMID: 36482689 DOI: 10.1021/acs.jnatprod.2c00781] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A chemical investigation of strain RD003821, belonging to the underexplored actinomycetes genus Krasilnikovia, led to the discovery of three novel polyketides: two 20-membered glycomacrolides, krasilnikolides A (1) and B (2), and an aglycone of 1, detalosylkrasilnikolide A (3). A major challenge in the structure elucidation of 1 was to determine the anomeric configuration of the α-l-6-deoxytalose (6dTal) unit, which was achieved by J-based configuration analysis (JBCA) that incorporated anomeric carbon- and proton-specific two-bond 13C-1H spin-spin coupling constants as diagnostic parameters. The updated criteria for the conformation/configuration assignment facilitated discrimination of three out of four stereochemical variants at the anomeric and the adjacent C2 positions, which expanded the scope of the JBCA method to determination of the anomeric configuration of aldohexopyranoses. Compounds 1 and 2 are the first macrolides decorated by 6dTal. Compounds 1-3 exhibited cytotoxicity against P388 murine leukemia cells with IC50 values of 14, 8.4, and 3.9 μM, respectively. In addition, 1-3 were antibacterial against the Gram-positive bacterium Kocuria rhizophila with MIC values of 25, 50, and 100 μg/mL. 1 was inhibitory against Staphylococcus aureus with an MIC of 50 μg/mL.
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Affiliation(s)
- Shiyang Lu
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Tao Zhou
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Keisuke Fukaya
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Enjuro Harunari
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Naoya Oku
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Daisuke Urabe
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Yasuhiro Igarashi
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
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Harunari E, Mae S, Fukaya K, Tashiro E, Urabe D, Igarashi Y. Bisprenyl naphthoquinone and chlorinated calcimycin congener bearing thiazole ring from an actinomycete of the genus Phytohabitans. J Antibiot (Tokyo) 2022; 75:542-551. [PMID: 36071213 DOI: 10.1038/s41429-022-00559-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 08/10/2022] [Accepted: 08/16/2022] [Indexed: 11/09/2022]
Abstract
A bisprenyl naphthoquinone, phytohabinone (1), and a calcimycin congener with unusual modifications, phytohabimicin (2), were isolated from the culture extract of Phytohabitans sp. RD003013. The structures of 1 and 2 were determined by NMR and MS analyses, and the absolute configuration of 2 was established by using electronic circular dichroism (ECD) calculation. The prenylation pattern of 1 was unprecedented among the known prenylated naphthoquinones. Compound 2 represents a spiroacetal core of polyketide origin substituted with a thiazole carboxylic acid and a dichrolopyrrole moiety, which is an unprecedented modification pattern in the known calcimycin family natural products. Remarkably, 2 showed moderate antimicrobial activity against a Gram-negative bacterium Ralstonia solanacearum while calcimycin was inactive. Additionally, 2 inhibits the migration of EC17 cancer cells at noncytotoxic concentrations.
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Affiliation(s)
- Enjuro Harunari
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama, 939-0398, Japan
| | - Shunsuke Mae
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama, 939-0398, Japan
| | - Keisuke Fukaya
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama, 939-0398, Japan
| | - Etsu Tashiro
- Showa Pharmaceutical University, 3-3165 Higashi-Tamagawagakuen, Machida, Tokyo, 194-8543, Japan
| | - Daisuke Urabe
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama, 939-0398, Japan
| | - Yasuhiro Igarashi
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama, 939-0398, Japan.
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Liu C, Zhang Z, Fukaya K, Urabe D, Harunari E, Oku N, Igarashi Y. Catellatolactams A-C, Plant Growth-Promoting Ansamacrolactams from a Rare Actinomycete of the Genus Catellatospora. JOURNAL OF NATURAL PRODUCTS 2022; 85:1993-1999. [PMID: 35948055 DOI: 10.1021/acs.jnatprod.2c00331] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Catellatolactams A-C (1-3), three novel ansamacrolactams, were isolated from the culture extract of an underexplored rare actinomycete of the genus Catellatospora. Spectroscopic and spectrometric analyses by NMR and MS elucidated the structure of 1 to be a lactamized pentaketide presumably extended on a 3-amino-5-hydroxybenzoic acid starter unit. Compounds 2 and 3 further received epoxidation and intramolecular cross-linking to incorporate a 2-indolinone unit, with a 3-amino-5-hydroxybenzoic acid pendant on 3. The absolute configurations of 2 and 3 were unequivocally established to both be 2S,6R,7R by comparison of the experimental NMR chemical shifts and ECD spectra with those predicted by DFT-based quantum chemical calculation. While 1-3 showed no appreciable antimicrobial activity or cytotoxicity, root elongation of germinated lettuce seeds was promoted by 2 and 3 at 1-10 μM.
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Affiliation(s)
- Chang Liu
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Zhiwei Zhang
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Keisuke Fukaya
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Daisuke Urabe
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Enjuro Harunari
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Naoya Oku
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Yasuhiro Igarashi
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
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Saito S, Suzuki S, Arai MA. Noaoxazole, a new heat shock metabolite produced by thermotolerant Streptomyces sp. HR41. J Antibiot (Tokyo) 2022; 75:509-513. [PMID: 35918479 DOI: 10.1038/s41429-022-00551-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 07/05/2022] [Accepted: 07/21/2022] [Indexed: 11/09/2022]
Abstract
The thermotolerant strain Streptomyces sp. HR41 was found to produce compound 1 only in a 45 °C culture, and not at the standard temperature. We previously designated this type of compound as a "heat shock metabolite" (HSM). NMR and MS analytical techniques were used to determine that the chemical structure of 1 comprised a methylated-oxazole ring and a linear chain moiety modified with a terminal amide group. Thus, 1 was shown to be a new curromycin analog, which we have designated noaoxazole (1). Compound 1 weakly activated Notch signal reporter activity without exhibiting cytotoxicity against assay cells at the same concentration.
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Affiliation(s)
- Shun Saito
- Department of Biosciences and Informatics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, 223-8522, Japan.
| | - Shiina Suzuki
- Department of Biosciences and Informatics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, 223-8522, Japan
| | - Midori A Arai
- Department of Biosciences and Informatics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, 223-8522, Japan.
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Saito S, Xiaohanyao Y, Zhou T, Nakajima-Shimada J, Tashiro E, Triningsih DW, Harunari E, Oku N, Igarashi Y. Phytohabitols A-C, δ-Lactone-Terminated Polyketides from an Actinomycete of the Genus Phytohabitans. JOURNAL OF NATURAL PRODUCTS 2022; 85:1697-1703. [PMID: 35708315 DOI: 10.1021/acs.jnatprod.2c00137] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Phytohabitols A-C (1-3), new terminally δ-lactonized linear polyketides, were isolated from the culture extract of a rare actinomycete of the genus Phytohabitans. The structures of 1-3, substituted with multiple methyl and hydroxy groups on a conjugated and a skipped diene-containing backbone, were elucidated by NMR and MS spectroscopic analyses. The absolute configuration of 1 was determined by chemical derivatization and chiral anisotropic analysis, coupled with ROESY and J-based configuration analysis. In addition, closely similar 1H and 13C NMR data and optical rotations among 1-3 supported the same stereochemistry of these polyketides. The related streptomycetes metabolites lagunapyrones B, C, and D have α-pyrone rings on the linear part in place of the δ-lactone, but their chirality at the C19-C21 stereocenters were opposite from those described here, posing a question on the previous assignment made solely by comparison of the optical rotations of four possible diastereomers. Compounds 1-3 inhibited migration of cancer cells with IC50 values of 15, 11, and 8.3 μM, respectively, at noncytotoxic concentrations. In addition, 1-3 displayed potent antitrypanosomal activity against Trypanosoma cruzi with IC50 values of 12, 6.4, and 18 μM, comparable to a commonly used therapeutic drug, benznidazole (IC50 16 μM).
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Affiliation(s)
- Shun Saito
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Ye Xiaohanyao
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Tao Zhou
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Junko Nakajima-Shimada
- Gunma University School of Health Sciences, 3-39-22 Showa-machi, Maebashi, Gunma 371-8511, Japan
| | - Etsu Tashiro
- Showa Pharmaceutical University, 3-3165 Higashi-Tamagawagakuen, Machida, Tokyo 194-8543, Japan
| | - Desy Wulan Triningsih
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Enjuro Harunari
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Naoya Oku
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Yasuhiro Igarashi
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
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Trehangelin E, a bisacyl trehalose with plant growth promoting activity from a rare actinomycete Polymorphospora sp. RD064483. J Antibiot (Tokyo) 2022; 75:296-300. [PMID: 35322208 DOI: 10.1038/s41429-022-00519-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 03/03/2022] [Accepted: 03/03/2022] [Indexed: 11/09/2022]
Abstract
Trehangelin E (1), a new bisacyl trehalose, was isolated from the culture extract of an actinomycete Polymorphospora sp. RD064483, along with three known congeners, trehangelins A, B, and D. Compound 1 is a new trehalose derivative acylated with (Z)-2-methyl-2-butenoic acid (angelic acid) at 3- and 6'-positions, as determined by NMR and MS analyses. Compound 1 promoted root elongation of germinated lettuce seeds by 30% at 1 μM and 90% at 10 μM compared to the nontreated seeds. Similar promoting activity of root elongation was also observed with trehangelins A and B at the same level.
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Saito S, Indo K, Oku N, Komaki H, Kawasaki M, Igarashi Y. Unsaturated fatty acids and a prenylated tryptophan derivative from a rare actinomycete of the genus Couchioplanes. Beilstein J Org Chem 2021; 17:2939-2949. [PMID: 34956414 PMCID: PMC8685556 DOI: 10.3762/bjoc.17.203] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Accepted: 12/03/2021] [Indexed: 11/23/2022] Open
Abstract
A genome mining survey combined with metabolome analysis of publicly available strains identified Couchioplanes sp. RD010705, a strain belonging to an underexplored genus of rare actinomycetes, as a producer of new metabolites. HPLC-DAD-guided fractionation of its fermentation extracts resulted in the isolation of five new methyl-branched unsaturated fatty acids, (2E,4E)-2,4-dimethyl-2,4-octadienoic acid (1), (2E,4E)-2,4,7-trimethyl-2,4-octadienoic acid (2), (R)-(-)-phialomustin B (3), (2E,4E)-7-hydroxy-2,4-dimethyl-2,4-octadienoic acid (4), (2E,4E)-7-hydroxy-2,4,7-trimethyl-2,4-octadienoic acid (5), and one prenylated tryptophan derivative, 6-(3,3-dimethylallyl)-N-acetyl-ʟ-tryptophan (6). The enantiomer ratio of 4 was determined to be approximately S/R = 56:44 by a recursive application of Trost's chiral anisotropy analysis and chiral HPLC analysis of its methyl ester. Compounds 1-5 were weakly inhibitory against Kocuria rhizophila at MIC 100 μg/mL and none were cytotoxic against P388 at the same concentration.
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Affiliation(s)
- Shun Saito
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
- Department of Biosciences and Informatics, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan
| | - Kanji Indo
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Naoya Oku
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Hisayuki Komaki
- Biological Resource Center, National Institute of Technology and Evaluation (NBRC), Kisarazu, Chiba 292-0818, Japan
| | - Masashi Kawasaki
- Center for Liberal Arts and Sciences, Faculty of Engineering, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Yasuhiro Igarashi
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
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