Marine Drugs

Research

12 pages, 2302 KiB

Open AccessArticle

Three New Isoflavonoid Glycosides from the Mangrove-Derived Actinomycete Micromonospora aurantiaca 110B

by Rui-Jun Wang, Shao-Yong Zhang, Yang-Hui Ye, Zhen Yu, Huan Qi, Hui Zhang, Zheng-Lian Xue, Ji-Dong Wang and Min Wu

Mar. Drugs 2019, 17(5), 294; https://doi.org/10.3390/md17050294 - 17 May 2019

Cited by 20 | Viewed by 3878

Abstract

The mangrove ecosystem is a rich resource for the discovery of actinomycetes with potential applications in pharmaceutical science. Besides the genus Streptomyces, Micromonospora is also a source of new bioactive agents. We screened Micromonospora from the rhizosphere soil of mangrove plants in [...] Read more.

The mangrove ecosystem is a rich resource for the discovery of actinomycetes with potential applications in pharmaceutical science. Besides the genus Streptomyces, Micromonospora is also a source of new bioactive agents. We screened Micromonospora from the rhizosphere soil of mangrove plants in Fujian province, China, and 51 strains were obtained. Among them, the extracts of 12 isolates inhibited the growth of human lung carcinoma A549 cells. Strain 110B exhibited better cytotoxic activity, and its bioactive constituents were investigated. Consequently, three new isoflavonoid glycosides, daidzein-4′-(2-deoxy-α-l-fucopyranoside) (1), daidzein-7-(2-deoxy-α-l-fucopyranoside) (2), and daidzein-4′,7-di-(2-deoxy-α-l-fucopyranoside) (3) were isolated from the fermentation broth of strain 110B. The structures of the new compounds were determined by spectroscopic methods, including 1D and 2D nuclear magnetic resonance (NMR) and high-resolution electrospray ionization mass spectrometry (HR-ESIMS). The result of medium-changing experiments implicated that these new compounds were microbial biotransformation products of strain M. aurantiaca 110B. The three compounds displayed moderate cytotoxic activity to the human lung carcinoma cell line A549, hepatocellular liver carcinoma cell line HepG2, and the human colon tumor cell line HCT116, whereas none of them showed antifungal or antibacterial activities. Full article

(This article belongs to the Special Issue Natural Products from Marine Actinomycetes)

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10 pages, 5780 KiB

Open AccessArticle

Cytotoxic, Anti-Migration, and Anti-Invasion Activities on Breast Cancer Cells of Angucycline Glycosides Isolated from a Marine-Derived Streptomyces sp.

by Xin-Ying Qu, Jin-Wei Ren, Ai-Hong Peng, Shi-Qi Lin, Dan-Dan Lu, Qian-Qian Du, Ling Liu, Xia Li, Er-Wei Li and Wei-Dong Xie

Mar. Drugs 2019, 17(5), 277; https://doi.org/10.3390/md17050277 - 9 May 2019

Cited by 16 | Viewed by 4760

Abstract

Four angucycline glycosides were previously characterized from marine-derived Streptomyces sp. OC1610.4. Further investigation of this strain cultured on different fermentation media from that used previously resulted in the isolation of two new angucycline glycosides, vineomycins E and F (1–2), [...] Read more.

Four angucycline glycosides were previously characterized from marine-derived Streptomyces sp. OC1610.4. Further investigation of this strain cultured on different fermentation media from that used previously resulted in the isolation of two new angucycline glycosides, vineomycins E and F (1–2), and five known homologues, grincamycin L (3), vineomycinone B₂ (4), fridamycin D (5), moromycin B (7), and saquayamycin B₁ (8). Vineomycin F (2) contains an unusual ring-cleavage deoxy sugar. All the angucycline glycosides isolated from Streptomyces sp. OC1610.4 were evaluated for their cytotoxic activity against breast cancer cells MCF-7, MDA-MB-231, and BT-474. Moromycin B (7), saquayamycin B₁ (8), and saquayamycin B (9) displayed potent anti-proliferation against the tested cell lines, with IC₅₀ values ranging from 0.16 to 0.67 μM. Saquayamycin B (9) inhibited the migration and invasion of MDA-MB-231 cells in a dose-dependent manner, as detected by Transwell and wound-healing assays. Full article

(This article belongs to the Special Issue Natural Products from Marine Actinomycetes)

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13 pages, 1300 KiB

Open AccessArticle

Identification of the Actinomycin D Biosynthetic Pathway from Marine-Derived Streptomyces costaricanus SCSIO ZS0073

by Mengchan Liu, Yanxi Jia, Yunchang Xie, Chunyan Zhang, Junying Ma, Changli Sun and Jianhua Ju

Mar. Drugs 2019, 17(4), 240; https://doi.org/10.3390/md17040240 - 23 Apr 2019

Cited by 37 | Viewed by 5937

Abstract

Bioactive secondary metabolites from Streptomycetes are important sources of lead compounds in current drug development. Streptomyces costaricanus SCSIO ZS0073, a mangrove-derived actinomycete, produces actinomycin D, a clinically used therapeutic for Wilm’s tumor of the kidney, trophoblastic tumors and rhabdomyosarcoma. In this work, we [...] Read more.

Bioactive secondary metabolites from Streptomycetes are important sources of lead compounds in current drug development. Streptomyces costaricanus SCSIO ZS0073, a mangrove-derived actinomycete, produces actinomycin D, a clinically used therapeutic for Wilm’s tumor of the kidney, trophoblastic tumors and rhabdomyosarcoma. In this work, we identified the actinomycin biosynthetic gene cluster (BGC) acn by detailed analyses of the S. costaricanus SCSIO ZS0073 genome. This organism produces actinomycin D with a titer of ~69.8 μg mL⁻¹ along with traces of actinomycin X_oβ. The acn cluster localized to a 39.8 kb length region consisting of 25 open reading frames (ORFs), including a set of four genes that drive the construction of the 4-methyl-3-hydroxy-anthranilic acid (4-MHA) precursor and three non-ribosomal peptide synthetases (NRPSs) that generate the 4-MHA pentapeptide semi-lactone, which, upon dimerization, affords final actinomycin D. Furthermore, the acn cluster contains four positive regulatory genes acnWU4RO, which were identified by in vivo gene inactivation studies. Our data provide insights into the genetic characteristics of this new mangrove-derived actinomycin D bioproducer, enabling future metabolic engineering campaigns to improve both titers and the structural diversities possible for actinomycin D and related analogues. Full article

(This article belongs to the Special Issue Natural Products from Marine Actinomycetes)

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13 pages, 2052 KiB

Open AccessArticle

Characterization of Two Toxin-Antitoxin Systems in Deep-Sea Streptomyces sp. SCSIO 02999

by Waner Zhan, Jianyun Yao, Kaihao Tang, Yangmei Li, Yunxue Guo and Xiaoxue Wang

Mar. Drugs 2019, 17(4), 211; https://doi.org/10.3390/md17040211 - 4 Apr 2019

Cited by 3 | Viewed by 3689

Abstract

Toxin-antitoxin (TA) systems are ubiquitous and abundant genetic elements in bacteria and archaea. Most previous TA studies have focused on commensal and pathogenic bacteria, but have rarely focused on marine bacteria, especially those isolated from the deep sea. Here, we identified and characterized [...] Read more.

Toxin-antitoxin (TA) systems are ubiquitous and abundant genetic elements in bacteria and archaea. Most previous TA studies have focused on commensal and pathogenic bacteria, but have rarely focused on marine bacteria, especially those isolated from the deep sea. Here, we identified and characterized three putative TA pairs in the deep-sea-derived Streptomyces sp. strain SCSIO 02999. Our results showed that Orf5461/Orf5462 and Orf2769/Orf2770 are bona fide TA pairs. We provide several lines of evidence to demonstrate that Orf5461 and Orf5462 constitute a type-II TA pair that are homologous to the YoeB/YefM TA pair from Escherichia coli. Although YoeB from SCSIO 02999 was toxic to an E. coli host, the homologous YefM antitoxin from SCSIO 02999 did not neutralize the toxic effect of YoeB from E. coli. For the Orf2769/Orf2770 TA pair, Orf2769 overexpression caused significant cell elongation and could lead to cell death in E. coli, and the neighboring Orf2770 could neutralize the toxic effect of Orf2769. However, no homologous toxin or antitoxin was found for this pair, and no direct interaction was found between Orf2769 and Orf2770. These results suggest that Orf2769 and Orf2770 may constitute a novel TA pair. Thus, deep-sea bacteria harbor typical and novel TA pairs. The biochemical and physiological functions of different TAs in deep-sea bacteria warrant further investigation. Full article

(This article belongs to the Special Issue Natural Products from Marine Actinomycetes)

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7 pages, 608 KiB

Open AccessArticle

Two New Piperazine-Triones from a Marine-Derived Streptomycetes sp. Strain SMS636

by Xiuli Xu, Jiahui Han, Rui Lin, Steven W. Polyak and Fuhang Song

Mar. Drugs 2019, 17(3), 186; https://doi.org/10.3390/md17030186 - 21 Mar 2019

Cited by 12 | Viewed by 3992

Abstract

Two new piperazine-triones lansai E and F (1, 2), together with four known secondary metabolites lansai D (3), 1-N-methyl-(E,Z)-albonoursin (4), imidazo[4,5-e]-1,2,4-triazine (5), and streptonigrin (6) were [...] Read more.

Two new piperazine-triones lansai E and F (1, 2), together with four known secondary metabolites lansai D (3), 1-N-methyl-(E,Z)-albonoursin (4), imidazo[4,5-e]-1,2,4-triazine (5), and streptonigrin (6) were isolated from a deep-sea-derived Streptomycetes sp. strain SMS636. The structures of the isolated compounds were confirmed by comprehensive spectroscopic analysis, including HRESIMS, 1D and 2D NMR. Compound 4 exhibited moderate antibacterial activities against Staphylococcus aureus and methicillin resistant S. aureus (MRSA) with Minimum Inhibitory Concentration (MIC) values of 12.5 and 25 μg/mL, respectively. Compound 6 displayed significant antibacterial activities against S. aureus, MRSA and Bacillus Calmette-Guérin (BCG) with MIC values of 0.78, 0.78 and 1.25 μg/mL, respectively. Full article

(This article belongs to the Special Issue Natural Products from Marine Actinomycetes)

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15 pages, 1961 KiB

Open AccessArticle

Acylated Aminooligosaccharides with Inhibitory Effects against α-Amylase from Streptomyces sp. HO1518

by Hai-Li Liu, Heng-Chao E, Ding-An Xie, Wen-Bo Cheng, Wan-Qi Tao and Yong Wang

Mar. Drugs 2018, 16(11), 403; https://doi.org/10.3390/md16110403 - 23 Oct 2018

Cited by 6 | Viewed by 3379

Abstract

Five new acylated aminooligosaccharides (1–5), together with one known related analogue (6), were isolated from Streptomyces sp. HO1518. Their structure was identified by extensive spectroscopic analysis, including 1D and 2D NMR data and high resolution electrospray ionization [...] Read more.

Five new acylated aminooligosaccharides (1–5), together with one known related analogue (6), were isolated from Streptomyces sp. HO1518. Their structure was identified by extensive spectroscopic analysis, including 1D and 2D NMR data and high resolution electrospray ionization mass spectrometry (HRESIMS), and by comparison with those reported in the literature. All of the new compounds showed more promising porcine pancreatic α-amylase (PPA) inhibitory activities than the clinical drug acarbose, indicating them as potential pharmaceutical drug leads toward type II diabetes. Full article

(This article belongs to the Special Issue Natural Products from Marine Actinomycetes)

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10 pages, 1707 KiB

Open AccessArticle

Seco-Tetracenomycins from the Marine-Derived Actinomycete Saccharothrix sp. 10-10

by Bin Liu, Jiao Li, Minghua Chen, Xiaomeng Hao, Fei Cao, Yi Tan, Yuhui Ping, Yiguang Wang, Chunling Xiao and Maoluo Gan

Mar. Drugs 2018, 16(10), 345; https://doi.org/10.3390/md16100345 - 20 Sep 2018

Cited by 9 | Viewed by 4127

Abstract

Six new tetracenomycin congeners, saccharothrixones E–I (1–5) and 13-de-O-methyltetracenomycin X (6), were isolated from the rare marine-derived actinomycete Saccharothrix sp. 10-10. Their structures were elucidated by spectroscopic analysis and time-dependent density functional theory (TDDFT)-electronic circular [...] Read more.

Six new tetracenomycin congeners, saccharothrixones E–I (1–5) and 13-de-O-methyltetracenomycin X (6), were isolated from the rare marine-derived actinomycete Saccharothrix sp. 10-10. Their structures were elucidated by spectroscopic analysis and time-dependent density functional theory (TDDFT)-electronic circular dichroism (ECD) calculations. Saccharothrixones G (3) and H (4) are the first examples of tetracenomycins featuring a novel ring-A-cleaved chromophore. Saccharothrixone I (5) was determined to be a seco-tetracenomycin derivative with ring-B cleavage. The new structural characteristics, highlighted by different oxidations at C-5 and cleavages in rings A and B, enrich the structural diversity of tetracenomycins and provide evidence for tetracenomycin biosynthesis. Analysis of the structure–activity relationship of these compounds confirmed the importance of the planarity of the naphthacenequinone chromophore and the methylation of the polar carboxy groups for tetracenomycin cytotoxicity. Full article

(This article belongs to the Special Issue Natural Products from Marine Actinomycetes)

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7 pages, 710 KiB

Open AccessCommunication

New Antibacterial Bagremycins F and G from the Marine-Derived Streptomyces sp. ZZ745

by Di Zhang, Chenyan Shu, Xiaoyuan Lian and Zhizhen Zhang

Mar. Drugs 2018, 16(9), 330; https://doi.org/10.3390/md16090330 - 12 Sep 2018

Cited by 23 | Viewed by 4250

Abstract

As part of our research to discover novel bioactive natural products from marine microorganisms, five bagremycin analogues, including the previously unreported bagremycins F (1) and G (2), were isolated from a marine actinomycete Streptomyces sp. ZZ745. The structures of [...] Read more.

As part of our research to discover novel bioactive natural products from marine microorganisms, five bagremycin analogues, including the previously unreported bagremycins F (1) and G (2), were isolated from a marine actinomycete Streptomyces sp. ZZ745. The structures of these compounds were determined by means of NMR spectroscopic analysis, HRESIMS data, and optical rotation. Both bagremycins F (1) and G (2) showed antibacterial activity against Escherichia coli, with MIC values of 41.8 and 61.7 μM, respectively. Full article

(This article belongs to the Special Issue Natural Products from Marine Actinomycetes)

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9 pages, 955 KiB

Open AccessArticle

Albisporachelin, a New Hydroxamate Type Siderophore from the Deep Ocean Sediment-Derived Actinomycete Amycolatopsis albispora WP1^T

by Qihao Wu, Robert W. Deering, Gaiyun Zhang, Bixia Wang, Xin Li, Jiadong Sun, Jianwei Chen, Huawei Zhang, David C. Rowley and Hong Wang

Mar. Drugs 2018, 16(6), 199; https://doi.org/10.3390/md16060199 - 7 Jun 2018

Cited by 15 | Viewed by 6498

Abstract

Marine actinobacteria continue to be a rich source for the discovery of structurally diverse secondary metabolites. Here we present a new hydroxymate siderophore produced by Amycolatopsis albispora, a recently described species of this less explored actinomycete genus. Strain WP1^T was isolated [...] Read more.

Marine actinobacteria continue to be a rich source for the discovery of structurally diverse secondary metabolites. Here we present a new hydroxymate siderophore produced by Amycolatopsis albispora, a recently described species of this less explored actinomycete genus. Strain WP1^T was isolated from sediments collected at −2945 m in the Indian Ocean. The new siderophore, designated albisporachelin, was isolated from iron depleted culture broths and the structure was established by 1D and 2D NMR and MS/MS experiments, and application of a modified Marfey’s method. Albisporachelin is composed of one N-methylated-formylated/hydroxylated l-ornithine (N-Me-fh-l-Orn), one l-serine (l-Ser), one formylated/hydroxylated l-ornithine (fh-l-Orn) and a cyclo-N-methylated-hydroxylated l-ornithine (cyclo-N-Me-h-l-Orn). Full article

(This article belongs to the Special Issue Natural Products from Marine Actinomycetes)

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10 pages, 4264 KiB

Open AccessArticle

Antartin, a Cytotoxic Zizaane-Type Sesquiterpenoid from a Streptomyces sp. Isolated from an Antarctic Marine Sediment

by Dayoung Kim, Eun Ju Lee, Jihye Lee, Alain S. Leutou, Yern-Hyerk Shin, Bomi Choi, Ji Sun Hwang, Dongyup Hahn, Hyukjae Choi, Jungwook Chin, Sung Jin Cho, Yong Deog Hong, Jaeyoung Ko, Chi Nam Seong, Katherine N. Maloney, Dong-Chan Oh, Inho Yang, Hayoung Hwang and Sang-Jip Nam

Mar. Drugs 2018, 16(4), 130; https://doi.org/10.3390/md16040130 - 16 Apr 2018

Cited by 18 | Viewed by 5319

Abstract

Antartin (1), a new zizaane-type sesquiterpene, was isolated from Streptomyces sp. SCO736. The chemical structure of 1 was assigned from the interpretation of 1D and 2D NMR in addition to mass spectrometric data. The relative stereochemistry of 1 was determined by [...] Read more.

Antartin (1), a new zizaane-type sesquiterpene, was isolated from Streptomyces sp. SCO736. The chemical structure of 1 was assigned from the interpretation of 1D and 2D NMR in addition to mass spectrometric data. The relative stereochemistry of 1 was determined by analysis of NOE data, while the absolute stereochemistry was decided based on a comparison of experimental and calculated electronic circular dichroism (ECD) spectra. Antartin (1) showed cytotoxicity against A549, H1299, and U87 cancer cell lines by causing cell cycle arrest at the G1 phase. Full article

(This article belongs to the Special Issue Natural Products from Marine Actinomycetes)

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9 pages, 1112 KiB

Open AccessCommunication

New Naphthoquinone Terpenoids from Marine Actinobacterium, Streptomyces sp. CNQ-509

by Jin-Soo Park and Hak Cheol Kwon

Mar. Drugs 2018, 16(3), 90; https://doi.org/10.3390/md16030090 - 12 Mar 2018

Cited by 19 | Viewed by 5910

Abstract

A member of the marine streptomycete clade MAR4, Streptomyces sp. CNQ-509, has genetic potential for the biosynthesis of hybrid isoprenoids and produces several meroterpenoids such as naphterpin, nitropyrrolin and marinophenazine. Our research on the strain CNQ-509 led to the isolation of two new [...] Read more.

A member of the marine streptomycete clade MAR4, Streptomyces sp. CNQ-509, has genetic potential for the biosynthesis of hybrid isoprenoids and produces several meroterpenoids such as naphterpin, nitropyrrolin and marinophenazine. Our research on the strain CNQ-509 led to the isolation of two new naphterpin derivatives (1 and 2) comprised of naphthoquinone and geranyl moieties along with the known terpenoid, debromomarinone. The two-dimensional structure of these compounds was determined through spectral data analysis using data from NMR, MS and UV spectroscopy. Furthermore, the full structures of 1 and 2 including absolute configurations were unequivocally established by a combination of NMR experiments and chemical modifications. Full article

(This article belongs to the Special Issue Natural Products from Marine Actinomycetes)

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14 pages, 1717 KiB

Open AccessArticle

Fluostatins M–Q Featuring a 6-5-6-6 Ring Skeleton and High Oxidized A-Rings from Marine Streptomyces sp. PKU-MA00045

by Jing Jin, Xiaoyan Yang, Tan Liu, Hua Xiao, Guiyang Wang, Mengjie Zhou, Fawang Liu, Yingtao Zhang, Dong Liu, Minghua Chen, Wei Cheng, Donghui Yang and Ming Ma

Mar. Drugs 2018, 16(3), 87; https://doi.org/10.3390/md16030087 - 9 Mar 2018

Cited by 33 | Viewed by 6801

Abstract

Aromatic polyketides from marine actinomycetes have received increasing attention due to their unusual structures and potent bioactivities. Compared to their terrestrial counterparts, marine aromatic polyketides have been less discovered and their structural and biological diversities are far from being fully investigated. In this [...] Read more.

Aromatic polyketides from marine actinomycetes have received increasing attention due to their unusual structures and potent bioactivities. Compared to their terrestrial counterparts, marine aromatic polyketides have been less discovered and their structural and biological diversities are far from being fully investigated. In this study, we employed a PCR-based genome mining method to discover aromatic polyketides in our marine bacteria collection. Five new atypical angucyclinones, fluostatins M–Q (1–5) featuring a unique 6-5-6-6 ring skeleton, were discovered from one “positive” Streptomyces sp. PKU-MA00045. The structures of fluostatins M–Q (1–5) were elucidated based on comprehensive spectroscopic analyses and the crystallographic structure of fluostatin P (4), which contains the most oxidized A-ring, was solved by X-ray diffraction analysis with Cu Kα radiation. Compared to the published 16 fluostatin analogues, fluostatins M–Q (1–5) contained a different methoxy group attached at C-7 and hydroxy group attached at C-4, enriching the structural diversity of aromatic polyketides from marine actinomycetes. Genome sequencing of Streptomyces sp. PKU-MA00045 revealed the biosynthetic gene cluster of fluostatins M–Q (1–5), which contained different genes and gene organizations compared to known fluostatin gene clusters, facilitating the investigation of the biosynthesis of the unique 6-5-6-6 ring skeleton in all fluostatins. Full article

(This article belongs to the Special Issue Natural Products from Marine Actinomycetes)

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9 pages, 596 KiB

Open AccessArticle

Lactomycins A–C, Dephosphorylated Phoslactomycin Derivatives that Inhibit Cathepsin B, from the Marine-derived Streptomyces sp. ACT232

by Yi Sun, Rogie Royce Carandang, Yuta Harada, Shigeru Okada, Kazutoshi Yoshitake, Shuichi Asakawa, Yuichi Nogi, Shigeki Matsunaga and Kentaro Takada

Mar. Drugs 2018, 16(2), 70; https://doi.org/10.3390/md16020070 - 21 Feb 2018

Cited by 6 | Viewed by 7107

Abstract

Three new polyketides, lactomycins A (1)–C (3), were isolated from the culture broth of a marine-derived Streptomyces sp. ACT232 as cathepsin B inhibitors. Their structures were determined by a combination of NMR and MS data analyses to be the dephosphorylated derivatives of a [...] Read more.

Three new polyketides, lactomycins A (1)–C (3), were isolated from the culture broth of a marine-derived Streptomyces sp. ACT232 as cathepsin B inhibitors. Their structures were determined by a combination of NMR and MS data analyses to be the dephosphorylated derivatives of a phoslactomycin class of metabolites. Lactomycins exhibited cathepsin B inhibitory activity (IC50 0.8 to 4.5 μg/mL). Even though the biosynthetic gene clusters found in the genome of the current strain have high similarity to those of phoslactomycin, neither phoslactomycins nor leustroducsins were detected by LC-MS analyses of the crude extract. Full article

(This article belongs to the Special Issue Natural Products from Marine Actinomycetes)

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939 KiB

Open AccessFeature PaperArticle

Saccharomonopyrones A–C, New α-Pyrones from a Marine Sediment-Derived Bacterium Saccharomonospora sp. CNQ-490

by Chae-Yoon Yim, Tu Cam Le, Tae Gu Lee, Inho Yang, Hansol Choi, Jusung Lee, Kyung-Yun Kang, Jin Sil Lee, Kyung-Min Lim, Sung-Tae Yee, Heonjoong Kang, Sang-Jip Nam and William Fenical

Mar. Drugs 2017, 15(8), 239; https://doi.org/10.3390/md15080239 - 3 Aug 2017

Cited by 23 | Viewed by 5678

Abstract

Intensive study of the organic extract of the marine-derived bacterium Saccharomonospora sp. CNQ-490 has yielded three new α-pyrones, saccharomonopyrones A–C (1–3). The chemical structures of these compounds were assigned from the interpretation of 1D, 2D NMR and mass spectrometry [...] Read more.

Intensive study of the organic extract of the marine-derived bacterium Saccharomonospora sp. CNQ-490 has yielded three new α-pyrones, saccharomonopyrones A–C (1–3). The chemical structures of these compounds were assigned from the interpretation of 1D, 2D NMR and mass spectrometry data. Saccharomonopyrone A (1) is the first α-pyrone microbial natural product bearing the ethyl-butyl ether chain in the molecule, while saccharomonopyrones B and C possess unusual 3-methyl and a 6-alkyl side-chain within a 3,4,5,6-tetrasubstituted α-pyrone moiety. Saccharomonopyrone A exhibited weak antioxidant activity using a cation radical scavenging activity assay with an IC₅₀ value of 140 μM. Full article

(This article belongs to the Special Issue Natural Products from Marine Actinomycetes)

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1773 KiB

Open AccessFeature PaperArticle

Strepchazolins A and B: Two New Alkaloids from a Marine Streptomyces chartreusis NA02069

by Cheng-Long Yang, Yi-Shuang Wang, Cheng-Li Liu, Ying-Jie Zeng, Ping Cheng, Rui-Hua Jiao, Shi-Xiang Bao, Hui-Qin Huang, Ren-Xiang Tan and Hui-Ming Ge

Mar. Drugs 2017, 15(8), 244; https://doi.org/10.3390/md15080244 - 2 Aug 2017

Cited by 33 | Viewed by 6533

Abstract

Two new alkaloids, strepchazolins A (1) and B (2), together with a previously reported compound, streptazolin (3), were isolated from a marine actinomycete, Streptomyces chartreusis NA02069, collected in the Coast of Hainan Island, China. The structures of [...] Read more.

Two new alkaloids, strepchazolins A (1) and B (2), together with a previously reported compound, streptazolin (3), were isolated from a marine actinomycete, Streptomyces chartreusis NA02069, collected in the Coast of Hainan Island, China. The structures of new compounds were determined by extensive NMR, mass spectroscopic and X-ray crystallographic analysis, as well as modified Mosher’s method. Compound 1 showed weak anti-Bacillus subtilis activity with the MIC value of 64.0 μM, and weak inhibitory activity against acetylcholinesterase (AChE) in vitro with IC₅₀ value of 50.6 μM, while its diastereoisomer, Compound 2, is almost inactive. Full article

(This article belongs to the Special Issue Natural Products from Marine Actinomycetes)

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881 KiB

Open AccessCommunication

Microindolinone A, a Novel 4,5,6,7-Tetrahydroindole, from the Deep-Sea-Derived Actinomycete Microbacterium sp. MCCC 1A11207

by Siwen Niu, Ting-Ting Zhou, Chun-Lan Xie, Gai-Yun Zhang and Xian-Wen Yang

Mar. Drugs 2017, 15(7), 230; https://doi.org/10.3390/md15070230 - 19 Jul 2017

Cited by 28 | Viewed by 5499

Abstract

A novel indole, microindolinone A (1), was isolated from a deep-sea-derived actinomycete Microbacterium sp. MCCC 1A11207, together with 18 known compounds (2–19). By detailed analysis of the ¹H, ¹³C, HSQC, COSY, HMBC, high resolution electron [...] Read more.

A novel indole, microindolinone A (1), was isolated from a deep-sea-derived actinomycete Microbacterium sp. MCCC 1A11207, together with 18 known compounds (2–19). By detailed analysis of the ¹H, ¹³C, HSQC, COSY, HMBC, high resolution electron spray ionization mass spectrum (HRESIMS), and circular dichroism (CD) data, the absolute configuration of 1 was elucidated as 5R-hydroxy-4,5,6,7-tetrahydroindole-4-one. It is noteworthy that 1 is the second example of a saturated indole isolated from nature. Full article

(This article belongs to the Special Issue Natural Products from Marine Actinomycetes)

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716 KiB

Open AccessArticle

Lobophorin K, a New Natural Product with Cytotoxic Activity Produced by Streptomyces sp. M-207 Associated with the Deep-Sea Coral Lophelia pertusa

by Alfredo F. Braña, Aida Sarmiento-Vizcaíno, Miguel Osset, Ignacio Pérez-Victoria, Jesús Martín, Nuria De Pedro, Mercedes De la Cruz, Caridad Díaz, Francisca Vicente, Fernando Reyes, Luis A. García and Gloria Blanco

Mar. Drugs 2017, 15(5), 144; https://doi.org/10.3390/md15050144 - 19 May 2017

Cited by 54 | Viewed by 8046

Abstract

The present article describes the isolation of a new natural product of the lobophorin family, designated as lobophorin K (1), from cultures of the marine actinobacteria Streptomyces sp. M-207, previously isolated from the cold-water coral Lophelia pertusa collected at 1800 m [...] Read more.

The present article describes the isolation of a new natural product of the lobophorin family, designated as lobophorin K (1), from cultures of the marine actinobacteria Streptomyces sp. M-207, previously isolated from the cold-water coral Lophelia pertusa collected at 1800 m depth during an expedition to the submarine Avilés Canyon. Its structure was determined using a combination of spectroscopic techniques, mainly ESI-TOF MS and 1D and 2D NMR. This new natural product displayed cytotoxic activity against two human tumor cell lines, such as pancreatic carcinoma (MiaPaca-2) and breast adenocarcinoma (MCF-7). Lobophorin K also displayed moderate and selective antibiotic activity against pathogenic Gram-positive bacteria such as Staphylococcus aureus. Full article

(This article belongs to the Special Issue Natural Products from Marine Actinomycetes)

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