Marine Drugs

Research

9 pages, 423 KiB

Open AccessArticle

Bioactive Isopimarane Diterpenes from the Fungus, Epicoccum sp. HS-1, Associated with Apostichopus japonicus

by Xuekui Xia, Jun Qi, Yayue Liu, Airong Jia, Yonggang Zhang, Changheng Liu, Cuiling Gao and Zhigang She

Mar. Drugs 2015, 13(3), 1124-1132; https://doi.org/10.3390/md13031124 - 2 Mar 2015

Cited by 24 | Viewed by 7037

Abstract

One new isopimarane diterpene (1), together with two known compounds, 11-deoxydiaporthein A (2) and iso-pimara-8(14),15-diene (3) were isolated from the culture of Epicoccum sp., which was associated with Apostichopus japonicus. Their structures were determined by the analysis [...] Read more.

One new isopimarane diterpene (1), together with two known compounds, 11-deoxydiaporthein A (2) and iso-pimara-8(14),15-diene (3) were isolated from the culture of Epicoccum sp., which was associated with Apostichopus japonicus. Their structures were determined by the analysis of 1D and 2D NMR, as well as mass spectroscopic data. The absolute configuration of Compound 1 was deduced by a single-crystal X-ray diffraction experiment using CuKα radiation. In the bioactivity assay, both Compounds 1 and 2 exhibited α-glucosidase inhibitory activity with IC₅₀ values of 4.6 ± 0.1 and 11.9 ± 0.4 μM, respectively. This was the first report on isopimarane diterpenes with α-glucosidase inhibitory activity. Full article

(This article belongs to the Special Issue Bioactive Compounds from Marine Microbes)

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16 pages, 968 KiB

Open AccessArticle

Biosynthesis of Akaeolide and Lorneic Acids and Annotation of Type I Polyketide Synthase Gene Clusters in the Genome of Streptomyces sp. NPS554

by Tao Zhou, Hisayuki Komaki, Natsuko Ichikawa, Akira Hosoyama, Seizo Sato and Yasuhiro Igarashi

Mar. Drugs 2015, 13(1), 581-596; https://doi.org/10.3390/md13010581 - 16 Jan 2015

Cited by 21 | Viewed by 9003

Abstract

The incorporation pattern of biosynthetic precursors into two structurally unique polyketides, akaeolide and lorneic acid A, was elucidated by feeding experiments with ¹³C-labeled precursors. In addition, the draft genome sequence of the producer, Streptomyces sp. NPS554, was performed and the biosynthetic gene [...] Read more.

The incorporation pattern of biosynthetic precursors into two structurally unique polyketides, akaeolide and lorneic acid A, was elucidated by feeding experiments with ¹³C-labeled precursors. In addition, the draft genome sequence of the producer, Streptomyces sp. NPS554, was performed and the biosynthetic gene clusters for these polyketides were identified. The putative gene clusters contain all the polyketide synthase (PKS) domains necessary for assembly of the carbon skeletons. Combined with the ¹³C-labeling results, gene function prediction enabled us to propose biosynthetic pathways involving unusual carbon-carbon bond formation reactions. Genome analysis also indicated the presence of at least ten orphan type I PKS gene clusters that might be responsible for the production of new polyketides. Full article

(This article belongs to the Special Issue Bioactive Compounds from Marine Microbes)

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13 pages, 710 KiB

Open AccessArticle

Asperlones A and B, Dinaphthalenone Derivatives from a Mangrove Endophytic Fungus Aspergillus sp. 16-5C

by Ze'en Xiao, Shao'e Lin, Chunbing Tan, Yongjun Lu, Lei He, Xishan Huang and Zhigang She

Mar. Drugs 2015, 13(1), 366-378; https://doi.org/10.3390/md13010366 - 13 Jan 2015

Cited by 33 | Viewed by 8401

Abstract

Racemic dinaphthalenone derivatives, (±)-asperlone A (1) and (±)-asperlone B (2), and two new azaphilones, 6′-hydroxy-(R)-mitorubrinic acid (3) and purpurquinone D (4), along with four known compounds, (−)-mitorubrinic acid (5), (−)-mitorubrin ( [...] Read more.

Racemic dinaphthalenone derivatives, (±)-asperlone A (1) and (±)-asperlone B (2), and two new azaphilones, 6′-hydroxy-(R)-mitorubrinic acid (3) and purpurquinone D (4), along with four known compounds, (−)-mitorubrinic acid (5), (−)-mitorubrin (6), purpurquinone A (7) and orsellinic acid (8), were isolated from the cultures of Aspergillus sp. 16-5C. The structures were elucidated using comprehensive spectroscopic methods, including 1D and 2D NMR spectra and the structures of 1 further confirmed by single-crystal X-ray diffraction analysis, while the absolute configuration of 3 and 4 were determined by comparing their optical rotation and CD with those of the literature, respectively. Compounds 1, 2 and 6 exhibited potent inhibitory effects against Mycobacterium tuberculosis protein tyrosine phosphatase B (MptpB) with IC₅₀ values of 4.24 ± 0.41, 4.32 ± 0.60 and 3.99 ± 0.34 μM, respectively. Full article

(This article belongs to the Special Issue Bioactive Compounds from Marine Microbes)

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13 pages, 619 KiB

Open AccessArticle

New Ikarugamycin Derivatives with Antifungal and Antibacterial Properties from Streptomyces zhaozhouensis

by Rodney Lacret, Daniel Oves-Costales, Cristina Gómez, Caridad Díaz, Mercedes De la Cruz, Ignacio Pérez-Victoria, Francisca Vicente, Olga Genilloud and Fernando Reyes

Mar. Drugs 2015, 13(1), 128-140; https://doi.org/10.3390/md13010128 - 29 Dec 2014

Cited by 85 | Viewed by 11180

Abstract

A bioassay guided fractionation of the ethyl acetate extract from culture broths of the strain Streptomyces zhaozhouensis CA-185989 led to the isolation of three new polycyclic tetramic acid macrolactams (1–3) and four known compounds. All the new compounds were [...] Read more.

A bioassay guided fractionation of the ethyl acetate extract from culture broths of the strain Streptomyces zhaozhouensis CA-185989 led to the isolation of three new polycyclic tetramic acid macrolactams (1–3) and four known compounds. All the new compounds were structurally related to the known Streptomyces metabolite ikarugamycin (4). Their structural elucidation was accomplished using a combination of electrospray-time of flight mass spectrometry (ESI-TOF MS) and 1D and 2D NMR analyses. Compounds 1–3 showed antifungal activity against Aspergillus fumigatus, Candida albicans and antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA). Full article

(This article belongs to the Special Issue Bioactive Compounds from Marine Microbes)

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17 pages, 1041 KiB

Open AccessArticle

Chromomycin A2 Induces Autophagy in Melanoma Cells

by Larissa Alves Guimarães, Paula Christine Jimenez, Thiciana Da Silva Sousa, Hozana Patrícia S. Freitas, Danilo Damasceno Rocha, Diego Veras Wilke, Jesús Martín, Fernando Reyes, Otília Deusdênia Loiola Pessoa and Letícia Veras Costa-Lotufo

Mar. Drugs 2014, 12(12), 5839-5855; https://doi.org/10.3390/md12125839 - 4 Dec 2014

Cited by 23 | Viewed by 7548

Abstract

The present study highlights the biological effects of chromomycin A2 toward metastatic melanoma cells in culture. Besides chromomycin A2, chromomycin A3 and demethylchromomycin A2 were also identified from the extract derived from Streptomyces sp., recovered from Paracuru Beach, located in the northeast region [...] Read more.

The present study highlights the biological effects of chromomycin A2 toward metastatic melanoma cells in culture. Besides chromomycin A2, chromomycin A3 and demethylchromomycin A2 were also identified from the extract derived from Streptomyces sp., recovered from Paracuru Beach, located in the northeast region of Brazil. The cytotoxic activity of chromomycin A2 was evaluated across a panel of human tumor cell lines, which found IC₅₀ values in the nM-range for exposures of 48 and 72 h. MALME-3M, a metastatic melanoma cell line, showed the highest sensitivity to chromomycin A2 after 48h incubation, and was chosen as a model to investigate this potent cytotoxic effect. Treatment with chromomycin A2 at 30 nM reduced cell proliferation, but had no significant effect upon cell viability. Additionally, chromomycin A2 induced accumulation of cells in G₀/G₁ phase of the cell cycle, with consequent reduction of S and G₂/M and unbalanced expression of cyclins. Chromomycin A2 treated cells depicted several cellular fragments resembling autophagosomes and increased expression of proteins LC3-A and LC3-B. Moreover, exposure to chromomycin A2 also induced the appearance of acidic vacuolar organelles in treated cells. These features combined are suggestive of the induction of autophagy promoted by chromomycin A2, a feature not previously described for chromomycins. Full article

(This article belongs to the Special Issue Bioactive Compounds from Marine Microbes)

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20 pages, 1039 KiB

Open AccessArticle

Global and Phylogenetic Distribution of Quorum Sensing Signals, Acyl Homoserine Lactones, in the Family of Vibrionaceae

by Bastian Barker Rasmussen, Kristian Fog Nielsen, Henrique Machado, Jette Melchiorsen, Lone Gram and Eva C. Sonnenschein

Mar. Drugs 2014, 12(11), 5527-5546; https://doi.org/10.3390/md12115527 - 20 Nov 2014

Cited by 29 | Viewed by 8331 | Correction

Abstract

Bacterial quorum sensing (QS) and the corresponding signals, acyl homoserine lactones (AHLs), were first described for a luminescent Vibrio species. Since then, detailed knowledge has been gained on the functional level of QS; however, the abundance of AHLs in the family of Vibrionaceae [...] Read more.

Bacterial quorum sensing (QS) and the corresponding signals, acyl homoserine lactones (AHLs), were first described for a luminescent Vibrio species. Since then, detailed knowledge has been gained on the functional level of QS; however, the abundance of AHLs in the family of Vibrionaceae in the environment has remained unclear. Three hundred and one Vibrionaceae strains were collected on a global research cruise and the prevalence and profile of AHL signals in this global collection were determined. AHLs were detected in 32 of the 301 strains using Agrobacterium tumefaciens and Chromobacterium violaceum reporter strains. Ethyl acetate extracts of the cultures were analysed by ultra-high performance liquid chromatography-high resolution mass spectrometry (MS) with automated tandem MS confirmation for AHLs. N-(3-hydroxy-hexanoyl) (OH-C6) and N-(3-hydroxy-decanoyl) (OH-C10) homoserine lactones were the most common AHLs found in 17 and 12 strains, respectively. Several strains produced a diversity of different AHLs, including N-heptanoyl (C7) HL. AHL-producing Vibrionaceae were found in polar, temperate and tropical waters. The AHL profiles correlated with strain phylogeny based on gene sequence homology, however not with geographical location. In conclusion, a wide range of AHL signals are produced by a number of clades in the Vibrionaceae family and these results will allow future investigations of inter- and intra-species interactions within this cosmopolitan family of marine bacteria. Full article

(This article belongs to the Special Issue Bioactive Compounds from Marine Microbes)

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19 pages, 2350 KiB

Open AccessArticle

Sensitivity of Neurospora crassa to a Marine-Derived Aspergillus tubingensis Anhydride Exhibiting Antifungal Activity That Is Mediated by the MAS1 Protein

by Liat Koch, Anat Lodin, Inbal Herold, Micha Ilan, Shmuel Carmeli and Oded Yarden

Mar. Drugs 2014, 12(9), 4713-4731; https://doi.org/10.3390/md12094713 - 1 Sep 2014

Cited by 30 | Viewed by 9918

Abstract

The fungus Aspergillus tubingensis (strain OY907) was isolated from the Mediterranean marine sponge Ircinia variabilis. Extracellular extracts produced by this strain were found to inhibit the growth of several fungi. Among the secreted extract components, a novel anhydride metabolite, tubingenoic anhydride A [...] Read more.

The fungus Aspergillus tubingensis (strain OY907) was isolated from the Mediterranean marine sponge Ircinia variabilis. Extracellular extracts produced by this strain were found to inhibit the growth of several fungi. Among the secreted extract components, a novel anhydride metabolite, tubingenoic anhydride A (1) as well as the known 2-carboxymethyl-3-hexylmaleic acid anhydride, asperic acid, and campyrone A and C were purified and their structure elucidated. Compound 1 and 2-carboxymethyl-3-hexylmaleic acid anhydride inhibited Neurospora crassa growth (MIC = 330 and 207 μM, respectively) and affected hyphal morphology. We produced a N. crassa mutant exhibiting tolerance to 1 and found that a yet-uncharacterized gene, designated mas-1, whose product is a cytosolic protein, confers sensitivity to this compound. The ∆mas-1 strain showed increased tolerance to sublethal concentrations of the chitin synthase inhibitor polyoxin D, when compared to the wild type. In addition, the expression of chitin synthase genes was highly elevated in the ∆mas-1 strain, suggesting the gene product is involved in cell wall biosynthesis and the novel anhydride interferes with its function. Full article

(This article belongs to the Special Issue Bioactive Compounds from Marine Microbes)

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12 pages, 864 KiB

Open AccessArticle

Eurothiocin A and B, Sulfur-Containing Benzofurans from a Soft Coral-Derived Fungus Eurotium rubrum SH-823

by Zhaoming Liu, Guoping Xia, Senhua Chen, Yayue Liu, Hanxiang Li and Zhigang She

Mar. Drugs 2014, 12(6), 3669-3680; https://doi.org/10.3390/md12063669 - 20 Jun 2014

Cited by 52 | Viewed by 8880

Abstract

Two new sulfur-containing benzofuran derivatives, eurothiocin A and B (1 and 2), along with five known compounds, zinniol (3), butyrolactone I (4), aspernolide D (5), vermistatin (6), and methoxyvermistatin (7), were [...] Read more.

Two new sulfur-containing benzofuran derivatives, eurothiocin A and B (1 and 2), along with five known compounds, zinniol (3), butyrolactone I (4), aspernolide D (5), vermistatin (6), and methoxyvermistatin (7), were isolated from the cultures of Eurotium rubrum SH-823, a fungus obtained from a Sarcophyton sp. soft coral collected from the South China Sea. The new compounds (1 and 2) share a methyl thiolester moiety, which is quite rare among natural secondary metabolites. The structures of these metabolites were assigned on the basis of detailed spectroscopic analysis. The absolute configurations of 1 and 2 were determined by comparison of the experimental and calculated electronic circular dichroism (ECD) data. Compounds 1 and 2 exhibited more potent inhibitory effects against α-glucosidase activity than the clinical α-glucosidase inhibitor acarbose. Further mechanistic analysis showed that both of them exhibited competitive inhibition characteristics. Full article

(This article belongs to the Special Issue Bioactive Compounds from Marine Microbes)

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9 pages, 614 KiB

Open AccessArticle

Violapyrones H and I, New Cytotoxic Compounds Isolated from Streptomyces sp. Associated with the Marine Starfish Acanthaster planci

by Hee Jae Shin, Hwa-Sun Lee, Jong Seok Lee, Junho Shin, Min Ah Lee, Hyi-Seung Lee, Yeon-Ju Lee, Jieun Yun and Jong Soon Kang

Mar. Drugs 2014, 12(6), 3283-3291; https://doi.org/10.3390/md12063283 - 30 May 2014

Cited by 34 | Viewed by 8059

Abstract

Two new α-pyrone derivatives, violapyrones H (1) and I (2), along with known violapyrones B (3) and C (4) were isolated from the fermentation broth of a marine actinomycete Streptomyces sp. The strain was derived [...] Read more.

Two new α-pyrone derivatives, violapyrones H (1) and I (2), along with known violapyrones B (3) and C (4) were isolated from the fermentation broth of a marine actinomycete Streptomyces sp. The strain was derived from a crown-of-thorns starfish, Acanthaster planci, collected from Chuuk, Federated States of Micronesia. The structures of violapyrones were elucidated by the analysis of 1D and 2D NMR and HR-ESIMS data. Violapyrones (1–4) exhibited cytotoxicity against 10 human cancer cell lines with GI₅₀ values of 1.10–26.12 μg/mL when tested using sulforhodamine B (SRB) assay. This is the first report on the cytotoxicity of violapyrones against cancer cell lines and the absolute configuration of violapyrone C. Full article

(This article belongs to the Special Issue Bioactive Compounds from Marine Microbes)

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17 pages, 769 KiB

Open AccessArticle

Alterporriol-Type Dimers from the Mangrove Endophytic Fungus, Alternaria sp. (SK11), and Their MptpB Inhibitions

by Guoping Xia, Jia Li, Hanxiang Li, Yuhua Long, Shao'e Lin, Yongjun Lu, Lei He, Yongcheng Lin, Lan Liu and Zhigang She

Mar. Drugs 2014, 12(5), 2953-2969; https://doi.org/10.3390/md12052953 - 16 May 2014

Cited by 32 | Viewed by 9042

Abstract

A new alterporriol-type anthranoid dimer, alterporriol S (1), along with seven known anthraquinone derivatives, (+)-aS-alterporriol C (2), hydroxybostrycin (3), halorosellinia A (4), tetrahydrobostrycin (5), 9α-hydroxydihydrodesoxybostrycin (6), austrocortinin (7 [...] Read more.

A new alterporriol-type anthranoid dimer, alterporriol S (1), along with seven known anthraquinone derivatives, (+)-aS-alterporriol C (2), hydroxybostrycin (3), halorosellinia A (4), tetrahydrobostrycin (5), 9α-hydroxydihydrodesoxybostrycin (6), austrocortinin (7) and 6-methylquinizarin (8), were isolated from the culture broth of the mangrove fungus, Alternaria sp. (SK11), from the South China Sea. Their structures and the relative configurations were elucidated using comprehensive spectroscopic methods, including 1D and 2D NMR spectra. The absolute configurations of 1 and the axial configuration of 2 were defined by experimental and theoretical ECD spectroscopy. 1 was identified as the first member of alterporriols consisting of a unique C-10−C-2′ linkage. Atropisomer 2 exhibited strong inhibitory activity against Mycobacterium tuberculosis protein tyrosine phosphatase B (MptpB) with an IC₅₀ value 8.70 μM. Full article

(This article belongs to the Special Issue Bioactive Compounds from Marine Microbes)

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9 pages, 230 KiB

Open AccessCommunication

Oleic Acid Produced by a Marine Vibrio spp. Acts as an Anti-Vibrio parahaemolyticus Agent

by Yanett Leyton, Jorge Borquez, José Darias, Mercedes Cueto, Ana R. Díaz-Marrero and Carlos Riquelme

Mar. Drugs 2011, 9(10), 2155-2163; https://doi.org/10.3390/md9102155 - 24 Oct 2011

Cited by 17 | Viewed by 7936

Abstract

It is known that some strains of Vibrio parahaemolyticus are responsible for gastroenteric diseases caused by the ingestion of marine organisms contaminated with these bacterial strains. Organic products that show inhibitory activity on the growth of the pathogenic V. parahaemolyticus were extracted from [...] Read more.

It is known that some strains of Vibrio parahaemolyticus are responsible for gastroenteric diseases caused by the ingestion of marine organisms contaminated with these bacterial strains. Organic products that show inhibitory activity on the growth of the pathogenic V. parahaemolyticus were extracted from a Vibrio native in the north of Chile. The inhibitory organic products were isolated by reverse phase chromatography and permeation by Sephadex LH20, and were characterized by spectroscopic and spectrometric techniques. The results showed that the prevailing active product is oleic acid, which was compared with standards by gas chromatography and high-performance liquid chromatography (HPLC). These active products might be useful for controlling the proliferation of pathogenic clones of V. parahaemolyticus. Full article

(This article belongs to the Special Issue Bioactive Compounds from Marine Microbes)

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12 pages, 1758 KiB

Open AccessArticle

Identification of the Antibacterial Compound Produced by the Marine Epiphytic Bacterium Pseudovibrio sp. D323 and Related Sponge-Associated Bacteria

by Anahit Penesyan, Jan Tebben, Matthew Lee, Torsten Thomas, Staffan Kjelleberg, Tilmann Harder and Suhelen Egan

Mar. Drugs 2011, 9(8), 1391-1402; https://doi.org/10.3390/md9081391 - 12 Aug 2011

Cited by 69 | Viewed by 12391

Abstract

Surface-associated marine bacteria often produce secondary metabolites with antagonistic activities. In this study, tropodithietic acid (TDA) was identified to be responsible for the antibacterial activity of the marine epiphytic bacterium Pseudovibrio sp. D323 and related strains. Phenol was also produced by these bacteria [...] Read more.

Surface-associated marine bacteria often produce secondary metabolites with antagonistic activities. In this study, tropodithietic acid (TDA) was identified to be responsible for the antibacterial activity of the marine epiphytic bacterium Pseudovibrio sp. D323 and related strains. Phenol was also produced by these bacteria but was not directly related to the antibacterial activity. TDA was shown to effectively inhibit a range of marine bacteria from various phylogenetic groups. However TDA-producers themselves were resistant and are likely to possess resistance mechanism preventing autoinhibition. We propose that TDA in isolate D323 and related eukaryote-associated bacteria plays a role in defending the host organism against unwanted microbial colonisation and, possibly, bacterial pathogens. Full article

(This article belongs to the Special Issue Bioactive Compounds from Marine Microbes)

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13 pages, 138 KiB

Open AccessArticle

Evaluation of Marine Brown Algae and Sponges from Brazil as Anticoagulant and Antiplatelet Products

by Laura de Andrade Moura, Fredy Ortiz-Ramirez, Diana Negrao Cavalcanti, Suzi Meneses Ribeiro, Guilherme Muricy, Valeria Laneuville Teixeira and Andre Lopes Fuly

Mar. Drugs 2011, 9(8), 1346-1358; https://doi.org/10.3390/md9081346 - 10 Aug 2011

Cited by 17 | Viewed by 9218

Abstract

The ischemic disorders, in which platelet aggregation and blood coagulation are involved, represent a major cause of disability and death worldwide. The antithrombotic therapy has unsatisfactory performance and may produce side effects. So, there is a need to seek molecules with antithrombotic properties. [...] Read more.

The ischemic disorders, in which platelet aggregation and blood coagulation are involved, represent a major cause of disability and death worldwide. The antithrombotic therapy has unsatisfactory performance and may produce side effects. So, there is a need to seek molecules with antithrombotic properties. Marine organisms produce substances with different well defined ecological functions. Moreover, some of these molecules also exhibit pharmacological properties such as antiviral, anticancer, antiophidic and anticoagulant properties. The aim of this study was to evaluate, through in vitro tests, the effect of two extracts of brown algae and ten marine sponges from Brazil on platelet aggregation and blood coagulation. Our results revealed that most of the extracts were capable of inhibiting platelet aggregation and clotting measured by plasma recalcification tests, prothrombin time, activated partial thromboplastin time, and fibrinogenolytic activity. On the other hand, five of ten species of sponges induced platelet aggregation. Thus, the marine organisms studied here may have molecules with antithrombotic properties, presenting biotechnological potential to antithrombotic therapy. Further chemical investigation should be conducted on the active species to discover useful molecules for the development of new drugs to treat clotting disorders. Full article

(This article belongs to the Special Issue Bioactive Compounds from Marine Microbes)

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12 pages, 332 KiB

Open AccessArticle

Three Bianthraquinone Derivatives from the Mangrove Endophytic Fungus Alternaria sp. ZJ9-6B from the South China Sea

by Cai-Huan Huang, Jia-Hui Pan, Bin Chen, Miao Yu, Hong-Bo Huang, Xun Zhu, Yong-Jun Lu, Zhi-Gang She and Yong-Cheng Lin

Mar. Drugs 2011, 9(5), 832-843; https://doi.org/10.3390/md9050832 - 12 May 2011

Cited by 101 | Viewed by 11855

Abstract

Three new bianthraquinone derivatives, alterporriol K (1), L (2) and M (3), along with six known compounds were obtained from extracts of the endophytic fungus Alternaria sp. ZJ9-6B, isolated from the mangrove Aegiceras corniculatum collected in the [...] Read more.

Three new bianthraquinone derivatives, alterporriol K (1), L (2) and M (3), along with six known compounds were obtained from extracts of the endophytic fungus Alternaria sp. ZJ9-6B, isolated from the mangrove Aegiceras corniculatum collected in the South China Sea. Their structures were elucidated by one- and two-dimensional NMR spectroscopy, MS data analysis and circular dichroism measurements. Compounds 1, 2 and 3 were first isolated alterporriols with a C-2–C-2′ linkage. The crystallographic data of tetrahydroaltersolanol B (7) was reported for the first time. In the primary bioassays, alterporriol K and L exhibited moderate cytotoxic activity towards MDA-MB-435 and MCF-7 cells with IC₅₀ values ranging from 13.1 to 29.1 µM. Full article

(This article belongs to the Special Issue Bioactive Compounds from Marine Microbes)

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16 pages, 279 KiB

Open AccessArticle

3-O-Methylfunicone, a Selective Inhibitor of Mammalian Y-Family DNA Polymerases from an Australian Sea Salt Fungal Strain

by Yoshiyuki Mizushina, Hirohisa Motoshima, Yasuhiro Yamaguchi, Toshifumi Takeuchi, Ken Hirano, Fumio Sugawara and Hiromi Yoshida

Mar. Drugs 2009, 7(4), 624-639; https://doi.org/10.3390/md7040624 - 23 Nov 2009

Cited by 41 | Viewed by 14230

Abstract

We isolated a pol inhibitor from the cultured mycelia extract of a fungal strain isolated from natural salt from a sea salt pan in Australia, which was identified as 3-O-methylfunicone by spectroscopic analyses. This compound selectively inhibited the activities of mammalian Y-family DNA [...] Read more.

We isolated a pol inhibitor from the cultured mycelia extract of a fungal strain isolated from natural salt from a sea salt pan in Australia, which was identified as 3-O-methylfunicone by spectroscopic analyses. This compound selectively inhibited the activities of mammalian Y-family DNA polymerases (pols) (i.e., pols η, ι and κ). Among these pols, human pol κ activity was most strongly inhibited, with an IC₅₀ value of 12.5 μM. On the other hand, the compound barely influenced the activities of the other families of mammalian pols, such as A-family (i.e., pol γ), B-family (i.e., pols α, δ and ε) or X-family (i.e., pols β, λ and terminal deoxynucleotidyl transferase), and showed no effect on the activities of fish pol δ, plant pols, prokaryotic pols and other DNA metabolic enzymes, such as calf primase of pol α, human immunodeficiency virus type-1 (HIV-1) reverse transcriptase, human telomerase, T7 RNA polymerase, mouse IMP dehydrogenase (type II), human topoisomerases I and II, T4 polynucleotide kinase or bovine deoxyribonuclease I. This compound also suppressed the growth of two cultured human cancer cell lines, HCT116 (colon carcinoma cells) and HeLa (cervix carcinoma cells), and UV-treated HeLa cells exhibited lower clonogenic survival in the presence of inhibitor. Full article

(This article belongs to the Special Issue Bioactive Compounds from Marine Microbes)

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26 pages, 249 KiB

Open AccessArticle

Preliminary Characterization of Extracellular Allelochemicals of the Toxic Marine Dinoflagellate Alexandrium tamarense Using a Rhodomonas salina Bioassay

by Haiyan Ma, Bernd Krock, Urban Tillmann and Allan Cembella

Mar. Drugs 2009, 7(4), 497-522; https://doi.org/10.3390/md7040497 - 2 Nov 2009

Cited by 78 | Viewed by 14271

Abstract

Members of the marine dinoflagellate genus Alexandrium are known to exude allelochemicals, unrelated to well-known neurotoxins (PSP-toxins, spirolides), with negative effects on other phytoplankton and marine grazers. Physico/chemical characterization of extracellular lytic compounds of A. tamarense, quantified by Rhodomonas salina bioassay, showed [...] Read more.

Members of the marine dinoflagellate genus Alexandrium are known to exude allelochemicals, unrelated to well-known neurotoxins (PSP-toxins, spirolides), with negative effects on other phytoplankton and marine grazers. Physico/chemical characterization of extracellular lytic compounds of A. tamarense, quantified by Rhodomonas salina bioassay, showed that the lytic activity, and hence presumably the compounds were stable over wide ranges of temperatures and pH and were refractory to bacterial degradation. Two distinct lytic fractions were collected by reversed-phase solid-phase extraction. The more hydrophilic fraction accounted for about 2% of the whole lytic activity of the A. tamarense culture supernatant, while the less hydrophilic one accounted for about 98% of activity. Although temporal stability of the compounds is high, substantial losses were evident during purification. Lytic activity was best removed from aqueous phase with chloroform-methanol (3:1). A “pseudo-loss” of lytic activity in undisturbed and low-concentrated samples and high activity of an emulsion between aqueous and n-hexane phase after liquid-liquid partition are strong evidence for the presence of amphipathic compounds. Lytic activity in the early fraction of gel permeation chromatography and lack of activity after 5 kD ultrafiltration indicate that the lytic agents form large aggregates or macromolecular complexes. Full article

(This article belongs to the Special Issue Bioactive Compounds from Marine Microbes)

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Review

Jump to: Research, Other

41 pages, 1197 KiB

Open AccessReview

Marine Extremophiles: A Source of Hydrolases for Biotechnological Applications

by Gabriel Zamith Leal Dalmaso, Davis Ferreira and Alane Beatriz Vermelho

Mar. Drugs 2015, 13(4), 1925-1965; https://doi.org/10.3390/md13041925 - 3 Apr 2015

Cited by 215 | Viewed by 21749

Abstract

The marine environment covers almost three quarters of the planet and is where evolution took its first steps. Extremophile microorganisms are found in several extreme marine environments, such as hydrothermal vents, hot springs, salty lakes and deep-sea floors. The ability of these microorganisms [...] Read more.

The marine environment covers almost three quarters of the planet and is where evolution took its first steps. Extremophile microorganisms are found in several extreme marine environments, such as hydrothermal vents, hot springs, salty lakes and deep-sea floors. The ability of these microorganisms to support extremes of temperature, salinity and pressure demonstrates their great potential for biotechnological processes. Hydrolases including amylases, cellulases, peptidases and lipases from hyperthermophiles, psychrophiles, halophiles and piezophiles have been investigated for these reasons. Extremozymes are adapted to work in harsh physical-chemical conditions and their use in various industrial applications such as the biofuel, pharmaceutical, fine chemicals and food industries has increased. The understanding of the specific factors that confer the ability to withstand extreme habitats on such enzymes has become a priority for their biotechnological use. The most studied marine extremophiles are prokaryotes and in this review, we present the most studied archaea and bacteria extremophiles and their hydrolases, and discuss their use for industrial applications. Full article

(This article belongs to the Special Issue Bioactive Compounds from Marine Microbes)

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14 pages, 565 KiB

Open AccessReview

Marine Pseudovibrio sp. as a Novel Source of Antimicrobials

by Susan P. Crowley, Fergal O'Gara, Orla O'Sullivan, Paul D. Cotter and Alan D. W. Dobson

Mar. Drugs 2014, 12(12), 5916-5929; https://doi.org/10.3390/md12125916 - 9 Dec 2014

Cited by 23 | Viewed by 8203

Abstract

Antibiotic resistance among pathogenic microorganisms is becoming ever more common. Unfortunately, the development of new antibiotics which may combat resistance has decreased. Recently, however the oceans and the marine animals that reside there have received increased attention as a potential source for natural [...] Read more.

Antibiotic resistance among pathogenic microorganisms is becoming ever more common. Unfortunately, the development of new antibiotics which may combat resistance has decreased. Recently, however the oceans and the marine animals that reside there have received increased attention as a potential source for natural product discovery. Many marine eukaryotes interact and form close associations with microorganisms that inhabit their surfaces, many of which can inhibit the attachment, growth or survival of competitor species. It is the bioactive compounds responsible for the inhibition that is of interest to researchers on the hunt for novel bioactives. The genus Pseudovibrio has been repeatedly identified from the bacterial communities isolated from marine surfaces. In addition, antimicrobial activity assays have demonstrated significant antimicrobial producing capabilities throughout the genus. This review will describe the potency, spectrum and possible novelty of the compounds produced by these bacteria, while highlighting the capacity for this genus to produce natural antimicrobial compounds which could be employed to control undesirable bacteria in the healthcare and food production sectors. Full article

(This article belongs to the Special Issue Bioactive Compounds from Marine Microbes)

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34 pages, 685 KiB

Open AccessReview

Microbial Communities and Bioactive Compounds in Marine Sponges of the Family Irciniidae—A Review

by Cristiane C. P. Hardoim and Rodrigo Costa

Mar. Drugs 2014, 12(10), 5089-5122; https://doi.org/10.3390/md12105089 - 30 Sep 2014

Cited by 39 | Viewed by 13981

Abstract

Marine sponges harbour complex microbial communities of ecological and biotechnological importance. Here, we propose the application of the widespread sponge family Irciniidae as an appropriate model in microbiology and biochemistry research. Half a gram of one Irciniidae specimen hosts hundreds of bacterial species—the [...] Read more.

Marine sponges harbour complex microbial communities of ecological and biotechnological importance. Here, we propose the application of the widespread sponge family Irciniidae as an appropriate model in microbiology and biochemistry research. Half a gram of one Irciniidae specimen hosts hundreds of bacterial species—the vast majority of which are difficult to cultivate—and dozens of fungal and archaeal species. The structure of these symbiont assemblages is shaped by the sponge host and is highly stable over space and time. Two types of quorum-sensing molecules have been detected in these animals, hinting at microbe-microbe and host-microbe signalling being important processes governing the dynamics of the Irciniidae holobiont. Irciniids are vulnerable to disease outbreaks, and concerns have emerged about their conservation in a changing climate. They are nevertheless amenable to mariculture and laboratory maintenance, being attractive targets for metabolite harvesting and experimental biology endeavours. Several bioactive terpenoids and polyketides have been retrieved from Irciniidae sponges, but the actual producer (host or symbiont) of these compounds has rarely been clarified. To tackle this, and further pertinent questions concerning the functioning, resilience and physiology of these organisms, truly multi-layered approaches integrating cutting-edge microbiology, biochemistry, genetics and zoology research are needed. Full article

(This article belongs to the Special Issue Bioactive Compounds from Marine Microbes)

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29 pages, 1137 KiB

Open AccessReview

Production of Bioactive Secondary Metabolites by Marine Vibrionaceae

by Maria Mansson, Lone Gram and Thomas O. Larsen

Mar. Drugs 2011, 9(9), 1440-1468; https://doi.org/10.3390/md9091440 - 25 Aug 2011

Cited by 116 | Viewed by 16891

Abstract

Bacteria belonging to the Vibrionaceae family are widespread in the marine environment. Today, 128 species of vibrios are known. Several of them are infamous for their pathogenicity or symbiotic relationships. Despite their ability to interact with eukaryotes, the vibrios are greatly underexplored for [...] Read more.

Bacteria belonging to the Vibrionaceae family are widespread in the marine environment. Today, 128 species of vibrios are known. Several of them are infamous for their pathogenicity or symbiotic relationships. Despite their ability to interact with eukaryotes, the vibrios are greatly underexplored for their ability to produce bioactive secondary metabolites and studies have been limited to only a few species. Most of the compounds isolated from vibrios so far are non-ribosomal peptides or hybrids thereof, with examples of N-containing compounds produced independent of nonribosomal peptide synthetases (NRPS). Though covering a limited chemical space, vibrios produce compounds with attractive biological activities, including antibacterial, anticancer, and antivirulence activities. This review highlights some of the most interesting structures from this group of bacteria. Many compounds found in vibrios have also been isolated from other distantly related bacteria. This cosmopolitan occurrence of metabolites indicates a high incidence of horizontal gene transfer, which raises interesting questions concerning the ecological function of some of these molecules. This account underlines the pending potential for exploring new bacterial sources of bioactive compounds and the challenges related to their investigation. Full article

(This article belongs to the Special Issue Bioactive Compounds from Marine Microbes)

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25 pages, 954 KiB

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Bacteriocin as Weapons in the Marine Animal-Associated Bacteria Warfare: Inventory and Potential Applications as an Aquaculture Probiotic

by Florie Desriac, Diane Defer, Nathalie Bourgougnon, Benjamin Brillet, Patrick Le Chevalier and Yannick Fleury

Mar. Drugs 2010, 8(4), 1153-1177; https://doi.org/10.3390/md8041153 - 4 Apr 2010

Cited by 141 | Viewed by 19756

Abstract

As the association of marine animals with bacteria has become more commonly recognized, researchers have increasingly questioned whether these animals actually produce many of the bioactive compounds originally isolated from them. Bacteriocins, ribosomally synthesized antibiotic peptides, constitute one of the most potent weapons [...] Read more.

As the association of marine animals with bacteria has become more commonly recognized, researchers have increasingly questioned whether these animals actually produce many of the bioactive compounds originally isolated from them. Bacteriocins, ribosomally synthesized antibiotic peptides, constitute one of the most potent weapons to fight against pathogen infections. Indeed, bacteriocinogenic bacteria may prevent pathogen dissemination by occupying the same ecological niche. Bacteriocinogenic strains associated with marine animals are a relevant source for isolation of probiotics. This review draws up an inventory of the marine bacteriocinogenic strains isolated from animal-associated microbial communities, known to date. Bacteriocin-like inhibitory substances (BLIS) and fully-characterized bacteriocins are described. Finally, their applications as probiotics in aquaculture are discussed. Full article

(This article belongs to the Special Issue Bioactive Compounds from Marine Microbes)

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23 pages, 196 KiB

Open AccessReview

Production of Metabolites as Bacterial Responses to the Marine Environment

by Carla C. C. R. De Carvalho and Pedro Fernandes

Mar. Drugs 2010, 8(3), 705-727; https://doi.org/10.3390/md8030705 - 17 Mar 2010

Cited by 161 | Viewed by 21224

Abstract

Bacteria in marine environments are often under extreme conditions of e.g., pressure, temperature, salinity, and depletion of micronutrients, with survival and proliferation often depending on the ability to produce biologically active compounds. Some marine bacteria produce biosurfactants, which help to transport hydrophobic low [...] Read more.

Bacteria in marine environments are often under extreme conditions of e.g., pressure, temperature, salinity, and depletion of micronutrients, with survival and proliferation often depending on the ability to produce biologically active compounds. Some marine bacteria produce biosurfactants, which help to transport hydrophobic low water soluble substrates by increasing their bioavailability. However, other functions related to heavy metal binding, quorum sensing and biofilm formation have been described. In the case of metal ions, bacteria developed a strategy involving the release of binding agents to increase their bioavailability. In the particular case of the Fe³⁺ ion, which is almost insoluble in water, bacteria secrete siderophores that form soluble complexes with the ion, allowing the cells to uptake the iron required for cell functioning. Adaptive changes in the lipid composition of marine bacteria have been observed in response to environmental variations in pressure, temperature and salinity. Some fatty acids, including docosahexaenoic and eicosapentaenoic acids, have only been reported in prokaryotes in deep-sea bacteria. Cell membrane permeability can also be adapted to extreme environmental conditions by the production of hopanoids, which are pentacyclic triterpenoids that have a function similar to cholesterol in eukaryotes. Bacteria can also produce molecules that prevent the attachment, growth and/or survival of challenging organisms in competitive environments. The production of these compounds is particularly important in surface attached strains and in those in biofilms. The wide array of compounds produced by marine bacteria as an adaptive response to demanding conditions makes them suitable candidates for screening of compounds with commercially interesting biological functions. Biosurfactants produced by marine bacteria may be helpful to increase mass transfer in different industrial processes and in the bioremediation of hydrocarbon-contaminated sites. Siderophores are necessary e.g., in the treatment of diseases with metal ion imbalance, while antifouling compounds could be used to treat man-made surfaces that are used in marine environments. New classes of antibiotics could efficiently combat bacteria resistant to the existing antibiotics. The present work aims to provide a comprehensive review of the metabolites produced by marine bacteria in order to cope with intrusive environments, and to illustrate how such metabolites can be advantageously used in several relevant areas, from bioremediation to health and pharmaceutical sectors. Full article

(This article belongs to the Special Issue Bioactive Compounds from Marine Microbes)

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22 pages, 172 KiB

Open AccessReview

Development of Novel Drugs from Marine Surface Associated Microorganisms

by Anahit Penesyan, Staffan Kjelleberg and Suhelen Egan

Mar. Drugs 2010, 8(3), 438-459; https://doi.org/10.3390/md8030438 - 1 Mar 2010

Cited by 213 | Viewed by 28560

Abstract

While the oceans cover more than 70% of the Earth’s surface, marine derived microbial natural products have been largely unexplored. The marine environment is a habitat for many unique microorganisms, which produce biologically active compounds (“bioactives”) to adapt to particular environmental conditions. For [...] Read more.

While the oceans cover more than 70% of the Earth’s surface, marine derived microbial natural products have been largely unexplored. The marine environment is a habitat for many unique microorganisms, which produce biologically active compounds (“bioactives”) to adapt to particular environmental conditions. For example, marine surface associated microorganisms have proven to be a rich source for novel bioactives because of the necessity to evolve allelochemicals capable of protecting the producer from the fierce competition that exists between microorganisms on the surfaces of marine eukaryotes. Chemically driven interactions are also important for the establishment of cross-relationships between microbes and their eukaryotic hosts, in which organisms producing antimicrobial compounds (“antimicrobials”), may protect the host surface against over colonisation in return for a nutrient rich environment. As is the case for bioactive discovery in general, progress in the detection and characterization of marine microbial bioactives has been limited by a number of obstacles, such as unsuitable culture conditions, laborious purification processes, and a lack of de-replication. However many of these limitations are now being overcome due to improved microbial cultivation techniques, microbial (meta-) genomic analysis and novel sensitive analytical tools for structural elucidation. Here we discuss how these technical advances, together with a better understanding of microbial and chemical ecology, will inevitably translate into an increase in the discovery and development of novel drugs from marine microbial sources in the future. Full article

(This article belongs to the Special Issue Bioactive Compounds from Marine Microbes)

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4 pages, 353 KiB

Open AccessCorrection

Correction: Rasmussen, B.B., et al. Global and Phylogenetic Distribution of Quorum Sensing Signals, Acyl Homoserine Lactones, in the Family of Vibrionaceae. Mar. Drugs 2014, 12, 5527–5546

by Bastian Barker Rasmussen, Kristian Fog Nielsen, Henrique Machado, Jette Melchiorsen, Lone Gram and Eva C. Sonnenschein

Mar. Drugs 2015, 13(3), 1548-1551; https://doi.org/10.3390/md13031548 - 20 Mar 2015

Viewed by 4879

Abstract

The authors wish to make the following corrections to this paper [1]: Due to duplicated and missing data in Table 3, Page 5533, replace: [...] Full article

(This article belongs to the Special Issue Bioactive Compounds from Marine Microbes)

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