The bacterial diversity associated with eroding sponges belonging to the Cliona viridis species complex is scarcely known. Cliona thomasi described from the West Coast of India is a new introduction to the viridis species complex. In this study, we determined the bacterial diversity associated with C. thomasi using next-generation sequencing. The results revealed the dominance of Proteobacteria followed by Cyanobacteria, Actinobacteria and Firmicutes. Among Proteobacteria, the Alphaproteobacteria were found to be the most dominant class. Furthermore, at the genus level, Rhodothalassium were highly abundant followed by Endozoicomonas in sponge samples. The beta-diversity and species richness measures showed remarkably lower diversity in Cliona thomasi than the ambient environment. The determined lower bacterial diversity in C. thomasi than the environmental samples, thus, categorized it as a low microbial abundance (LMA). Functional annotation of the C. thomasi-associated bacterial community indicates their possible role in photo-autotrophy, aerobic nitrification, coupling of sulphate reduction and sulphide oxidization. The present study unveils the bacterial diversity in bioeroding C. thomasi, which is a crucial step to determine the functions of the sponge holobiont in coral reef ecosystem.
Marine sponges represent a rich source of uncharacterized microbial diversity, and many are host to microorganisms that produce biologically active specialized metabolites. Here, a polyphasic approach was used to characterize two Actinobacteria strains, P01-B04T and P01-F02, that were isolated from the marine sponges Geodia barretti (Bowerbank, 1858) and Antho dichotoma (Esper, 1794), respectively. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strains P01-B04T and P01-F02 are closely related to Streptomyces beijiangensis DSM 41794T, Streptomyces laculatispora NRRL B-24909T, and Streptomyces brevispora NRRL B-24910T. The two strains showed nearly identical 16S rRNA gene sequences (99.93%), and the average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) relatedness values were 99.96% and 99.6%, respectively, suggesting that these strains are affiliated with the same species. Chemotaxonomic and culture characteristics of both strains were also consistent with the genus Streptomyces, while phenotypic properties, genome-based comparisons, and phylogenomic analyses distinguished strains P01-B04T and P01-F02 from their closest phylogenetic relatives. In silico analysis predicted that the 8.9 Mb genome of P01-B04T contains at least 41 biosynthetic gene clusters (BGCs) encoding secondary metabolites, indicating that this strain could express diverse bioactive metabolites; in support of this prediction, this strain expressed antibacterial activity against Gram-positive bacteria including a clinical isolate of methicillin-resistant Staphylococcus aureus (MRSA) EAMC30. Based on these results, the marine sponge-associated isolates represent a novel species of the genus Streptomyces, for which the name Streptomyces poriferorum sp. nov. is proposed, with P01-B04T (=DSM 111306T = CCM 9048T) as the type strain.
- MeSH
- Antibiosis * MeSH
- DNA, Bacterial genetics MeSH
- Phylogeny MeSH
- Nucleic Acid Hybridization MeSH
- Methicillin-Resistant Staphylococcus aureus MeSH
- Multigene Family MeSH
- Porifera * microbiology MeSH
- RNA, Ribosomal, 16S genetics MeSH
- Sequence Analysis, DNA MeSH
- Streptomyces * classification isolation & purification MeSH
- Bacterial Typing Techniques MeSH
- Base Composition MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
Marine sponges, a well-documented prolific source of natural products, harbor highly diverse microbial communities. Their extracts were previously shown to contain quorum sensing (QS) signal molecules of the N-acyl homoserine lactone (AHL) type, known to orchestrate bacterial gene regulation. Some bacteria and eukaryotic organisms are known to produce molecules that can interfere with QS signaling, thus affecting microbial genetic regulation and function. In the present study, we established the production of both QS signal molecules as well as QS inhibitory (QSI) molecules in the sponge species Sarcotragus spinosulus. A total of eighteen saturated acyl chain AHLs were identified along with six unsaturated acyl chain AHLs. Bioassay-guided purification led to the isolation of two brominated metabolites with QSI activity. The structures of these compounds were elucidated by comparative spectral analysis of 1HNMR and HR-MS data and were identified as 3-bromo-4-methoxyphenethylamine (1) and 5,6-dibromo-N,N-dimethyltryptamine (2). The QSI activity of compounds 1 and 2 was evaluated using reporter gene assays for long- and short-chain AHL signals (Escherichia coli pSB1075 and E. coli pSB401, respectively). QSI activity was further confirmed by measuring dose-dependent inhibition of proteolytic activity and pyocyanin production in Pseudomonas aeruginosa PAO1. The obtained results show the coexistence of QS and QSI in S. spinosulus, a complex signal network that may mediate the orchestrated function of the microbiome within the sponge holobiont.
- MeSH
- Escherichia coli drug effects physiology MeSH
- Virulence Factors MeSH
- Phylogeny MeSH
- Luminescent Measurements MeSH
- Porifera genetics metabolism microbiology MeSH
- Peptide Hydrolases chemistry pharmacology MeSH
- Pyocyanine chemistry pharmacology MeSH
- Quorum Sensing drug effects MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
Pregnane X Receptor (PXR) is a ligand-activated transcription factor which binds many structurally different molecules. The receptor is able to regulate the expression of a wide array of genes and is involved in cancer and different key physiological processes such as the metabolism of drugs/xenobiotics and endogenous compounds including lipids and carbohydrates, and inflammation. Algae, sponges, sea squirts, and other marine organisms are some of the species from which structurally new molecules have been isolated that have been subsequently identified in recent decades as ligands for PXR. The therapeutic potential of these natural compounds is promising in different areas and has recently resulted in the registration of trabectedin by the FDA as a novel antineoplastic drug. Apart from being potentially novel drugs, these compounds can also serve as models for the development of new molecules with improved activity. The aim of this review is to succinctly summarize the currently known natural molecules isolated from marine organisms with a proven ability to interact with PXR.
- MeSH
- Biological Products chemistry isolation & purification pharmacology MeSH
- Humans MeSH
- Ligands MeSH
- Molecular Structure MeSH
- Porifera chemistry MeSH
- Pregnane X Receptor metabolism MeSH
- Gene Expression Regulation drug effects MeSH
- Urochordata chemistry MeSH
- Aquatic Organisms chemistry MeSH
- Drug Development * MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Review MeSH
The high demand for new antibacterials fosters the isolation of new biologically active compounds producing actinobacteria. Here, we report the isolation and initial characterization of cultured actinobacteria from dominant benthic organisms' communities of Lake Baikal. Twenty-five distinct strains were obtained from 5 species of Baikal endemic macroinvertebrates of amphipods, freshwater sponges, turbellaria worms, and insects (caddisfly larvae). The 16S ribosomal RNA (rRNA)-based phylogenic analysis of obtained strains showed their affiliation to Streptomyces, Nocardia, Pseudonocardia, Micromonospora, Aeromicrobium, and Agromyces genera, revealing the diversity of actinobacteria associated with the benthic organisms of Lake Baikal. The biological activity assays showed that 24 out of 25 strains are producing compounds active against at least one of the test cultures used, including Gram-negative bacteria and Candida albicans. Complete dereplication of secondary metabolite profiles of two isolated strains led to identification of only few known compounds, while the majority of detected metabolites are not listed in existing antibiotic databases.
- MeSH
- Actinobacteria chemistry classification isolation & purification metabolism MeSH
- Amphipoda microbiology MeSH
- Anti-Infective Agents chemistry metabolism MeSH
- Bacteria drug effects MeSH
- Invertebrates microbiology MeSH
- Phylogeny MeSH
- Insecta microbiology MeSH
- Fungi drug effects MeSH
- Lakes microbiology MeSH
- Porifera microbiology MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
Isolation of unexplored frontier molecules are needed to treat multidrug resistant pathogens especially Methicillin resistant Staphylococcus aureus (MRSA). A marine sponge endosymbiotic Streptomyces albus ICN33 produces an anti-MRSA metabolite is reported. The crude extract exhibited anti-MRSA activity and the active principle was isolated through fermentation and chromatographic techniques. A compound PVI331 with a molecular mass of 506 Da have been determined by high resolution mass spectrometry. LC–MS based dereplication analysis had revealed that the detected compound PVI331 as unknown. The antibacterial assay of the compound PVI331 showed remarkable antagonistic activity against MRSA and Escherichia coli. Minimum inhibitory concentrations were found to be 1 μg/ml against MRSA. Sub-inhibitory concentration of the compound PVI331 reduced the biofilm formation of Staphylococcus aureus ATCC25923 and increased the cell surface hydrophobicity index. Scanning electron microscopic observation of the sub-inhibitory concentration exposure revealed a wrinkled membrane surface and slight cellular damage shows the cell wall distracting property of the compound. Zebrafish embryo based toxicity assays exhibited 48 ± 2 μg/ml of LC50 value and 30 μg/ml of compound as maximal non-lethal concentration which had demonstrated the positive relationship in safety index. This study highlighted the anti-MRSA property of Streptomyces albus ICN33 from a marine sponge.
- MeSH
- Anti-Bacterial Agents isolation & purification therapeutic use MeSH
- Biofilms drug effects MeSH
- Zebrafish MeSH
- Embryo, Nonmammalian drug effects MeSH
- Methicillin-Resistant Staphylococcus aureus * metabolism pathogenicity drug effects MeSH
- Porifera microbiology MeSH
- Streptomyces chemistry isolation & purification metabolism MeSH
- Dose-Response Relationship, Drug MeSH
- Publication type
- Research Support, Non-U.S. Gov't MeSH
Marine sponges are frequently inhabited by a wide range of associated invertebrates, including caridean shrimps. Symbiotic shrimps are often considered to be commensals; however, in most cases, the relationship with sponge hosts remains unclear. Here we demonstrate that sponge-inhabiting shrimps are often parasites adapted to consumption of sponge tissues. First, we provide detailed examination of morphology and stomach contents of Typton carneus (Decapoda: Palaemonidae: Pontoniinae), a West Atlantic tropical shrimp living in fire sponges of the genus Tedania. Remarkable shear-like claws of T. carneus show evidence of intensive shearing, likely the result of crushing siliceous sponge spicules. Examination of stomach contents revealed that the host sponge tissue is a major source of food for T. carneus. A parasitic mode of life is also reflected in adaptations of mouth appendages, in the reproduction strategy, and in apparent sequestration of host pigments by shrimp. Consistent results were obtained also for congeneric species T. distinctus (Western Atlantic) and T. spongicola (Mediterranean). The distribution of shrimps among sponge hosts (mostly solitary individuals or heterosexual pairs) suggests that Typton shrimps actively prevent colonisation of their sponge by additional conspecifics, thus protecting their resource and reducing the damage to the hosts. We also demonstrate feeding on host tissues by sponge-associated shrimps of the genera Onycocaris, Periclimenaeus, and Thaumastocaris (Pontoniinae) and Synalpheus (Alpheidae). The parasitic mode of life appears to be widely distributed among sponge-inhabiting shrimps. However, it is possible that under some circumstances, the shrimps provide a service to the host sponge by preventing a penetration by potentially more damaging associated animals. The overall nature of interspecific shrimp-sponge relationships thus warrants further investigation.
- MeSH
- Biological Evolution MeSH
- Decapoda physiology MeSH
- Phylogeny MeSH
- Adaptation, Physiological MeSH
- Host-Parasite Interactions MeSH
- Porifera parasitology MeSH
- Feeding Behavior MeSH
- Symbiosis MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Keywords
- makrocyklické sperminové alkaloidy, cyclochlorotin, polyricidiny, taxany,
- MeSH
- Amino Acids classification MeSH
- Anti-Infective Agents therapeutic use MeSH
- Anticarcinogenic Agents therapeutic use MeSH
- Edeine pharmacology MeSH
- Molecular Mechanisms of Pharmacological Action MeSH
- Phenylalanine analogs & derivatives pharmacology classification MeSH
- Geodia chemistry MeSH
- Humans MeSH
- Peptides pharmacology MeSH
- Plant Preparations pharmacology MeSH
- Spermine pharmacology MeSH
- Taxoids pharmacology MeSH
- Tyrosine analogs & derivatives pharmacology classification MeSH
- Check Tag
- Humans MeSH
The bengazoles are marine natural products with unique structure, containing two oxazole rings flanking a single carbon. They show very potent antifungal activity. The total syntheses of bengazole C and E are described following a convergent route which involves diastereoselective cycloaddition of an appropriately substituted nitrile oxide with a butane-1,2-diacetal-protected alkenediol as the key step.
- Keywords
- theonellapeptolidy,
- MeSH
- Peptides, Cyclic * chemistry isolation & purification MeSH
- Fertilization drug effects MeSH
- Chemistry, Clinical methods trends MeSH
- Lactones * chemistry isolation & purification MeSH
- Sperm Motility drug effects MeSH
- Antineoplastic Agents MeSH
- Plant Preparations therapeutic use MeSH
- Theonella chemistry MeSH
