scholarly journals Deep-Sea Fungi Could Be the New Arsenal for Bioactive Molecules

Marine Drugs ◽  
2019 ◽  
Vol 18 (1) ◽  
pp. 9 ◽  
Author(s):  
Muhammad Zain ul Arifeen ◽  
Yu-Nan Ma ◽  
Ya-Rong Xue ◽  
Chang-Hong Liu

Growing microbial resistance to existing drugs and the search for new natural products of pharmaceutical importance have forced researchers to investigate unexplored environments, such as extreme ecosystems. The deep-sea (>1000 m below water surface) has a variety of extreme environments, such as deep-sea sediments, hydrothermal vents, and deep-sea cold region, which are considered to be new arsenals of natural products. Organisms living in the extreme environments of the deep-sea encounter harsh conditions, such as high salinity, extreme pH, absence of sun light, low temperature and oxygen, high hydrostatic pressure, and low availability of growth nutrients. The production of secondary metabolites is one of the strategies these organisms use to survive in such harsh conditions. Fungi growing in such extreme environments produce unique secondary metabolites for defense and communication, some of which also have clinical significance. Despite being the producer of many important bioactive molecules, deep-sea fungi have not been explored thoroughly. Here, we made a brief review of the structure, biological activity, and distribution of secondary metabolites produced by deep-sea fungi in the last five years.

Marine Drugs ◽  
2020 ◽  
Vol 18 (12) ◽  
pp. 640
Author(s):  
Daniela Giordano

Marine organisms inhabiting extreme habitats are a promising reservoir of bioactive compounds for drug discovery. Extreme environments, i.e., polar and hot regions, deep sea, hydrothermal vents, marine areas of high pressure or high salinity, experience conditions close to the limit of life. In these marine ecosystems, “hot spots” of biodiversity, organisms have adopted a huge variety of strategies to cope with such harsh conditions, such as the production of bioactive molecules potentially valuable for biotechnological applications and for pharmaceutical, nutraceutical and cosmeceutical sectors. Many enzymes isolated from extreme environments may be of great interest in the detergent, textile, paper and food industries. Marine natural products produced by organisms evolved under hostile conditions exhibit a wide structural diversity and biological activities. In fact, they exert antimicrobial, anticancer, antioxidant and anti-inflammatory activities. The aim of this Special Issue “Bioactive Molecules from Extreme Environments” was to provide the most recent findings on bioactive molecules as well as enzymes isolated from extreme environments, to be used in biotechnological discovery pipelines and pharmaceutical applications, in an effort to encourage further research in these extreme habitats.


Metabolites ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 107
Author(s):  
Rafael de Felício ◽  
Patricia Ballone ◽  
Cristina Freitas Bazzano ◽  
Luiz F. G. Alves ◽  
Renata Sigrist ◽  
...  

Bacterial genome sequencing has revealed a vast number of novel biosynthetic gene clusters (BGC) with potential to produce bioactive natural products. However, the biosynthesis of secondary metabolites by bacteria is often silenced under laboratory conditions, limiting the controlled expression of natural products. Here we describe an integrated methodology for the construction and screening of an elicited and pre-fractionated library of marine bacteria. In this pilot study, chemical elicitors were evaluated to mimic the natural environment and to induce the expression of cryptic BGCs in deep-sea bacteria. By integrating high-resolution untargeted metabolomics with cheminformatics analyses, it was possible to visualize, mine, identify and map the chemical and biological space of the elicited bacterial metabolites. The results show that elicited bacterial metabolites correspond to ~45% of the compounds produced under laboratory conditions. In addition, the elicited chemical space is novel (~70% of the elicited compounds) or concentrated in the chemical space of drugs. Fractionation of the crude extracts further evidenced minor compounds (~90% of the collection) and the detection of biological activity. This pilot work pinpoints strategies for constructing and evaluating chemically diverse bacterial natural product libraries towards the identification of novel bacterial metabolites in natural product-based drug discovery pipelines.


Author(s):  
Yafei Chang ◽  
Qilian Fan ◽  
Jialin Hou ◽  
Yu Zhang ◽  
Jing Li

Abstract Microorganisms in deep-sea hydrothermal vents provide valuable insights into life under extreme conditions. Mass spectrometry-based proteomics has been widely used to identify protein expression and function. However, the metaproteomic studies in deep-sea microbiota have been constrained largely by the low identification rates of protein or peptide. To improve the efficiency of metaproteomics for hydrothermal vent microbiota, we firstly constructed a microbial gene database (HVentDB) based on 117 public metagenomic samples from hydrothermal vents and proposed a metaproteomic analysis strategy, which takes the advantages of not only the sample-matched metagenome, but also the metagenomic information released publicly in the community of hydrothermal vents. A two-stage false discovery rate method was followed up to control the risk of false positive. By applying our community-supported strategy to a hydrothermal vent sediment sample, about twice as many peptides were identified when compared with the ways against the sample-matched metagenome or the public reference database. In addition, more enriched and explainable taxonomic and functional profiles were detected by the HVentDB-based approach exclusively, as well as many important proteins involved in methane, amino acid, sugar, glycan metabolism and DNA repair, etc. The new metaproteomic analysis strategy will enhance our understanding of microbiota, including their lifestyles and metabolic capabilities in extreme environments. The database HVentDB is freely accessible from http://lilab.life.sjtu.edu.cn:8080/HventDB/main.html.


Life ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 292
Author(s):  
Lluvia Vargas-Gastélum ◽  
Meritxell Riquelme

The deep sea (>1000 m below sea level) represents one of the most extreme environments of the ocean. Despite exhibiting harsh abiotic conditions such as low temperatures, high hydrostatic pressure, high salinity concentrations, a low input of organic matter, and absence of light, the deep sea encompasses a great fungal diversity. For decades, most knowledge on the fungal diversity of the deep sea was obtained through culture-dependent techniques. More recently, with the latest advances of high-throughput next generation sequencing platforms, there has been a rapid increment in the number of studies using culture-independent techniques. This review brings into the spotlight the progress of the techniques used to assess the diversity and ecological role of the deep-sea mycobiota and provides an overview on how the omics technologies have contributed to gaining knowledge about fungi and their activity in poorly explored marine environments. Finally, current challenges and suggested coordinated efforts to overcome them are discussed.


2010 ◽  
Vol 73 (3) ◽  
pp. 489-499 ◽  
Author(s):  
Christopher C. Thornburg ◽  
T. Mark Zabriskie ◽  
Kerry L. McPhail

2021 ◽  
Vol 12 ◽  
Author(s):  
Yue Zhang ◽  
Ning Huang ◽  
Minxiao Wang ◽  
Hongbin Liu ◽  
Hongmei Jing

Microbial eukaryotes are key components of the marine food web, but their distribution in deep-sea chemosynthetic ecosystems has not been well studied. Here, high-throughput sequencing of the 18S rRNA gene and network analysis were applied to investigate the diversity, distribution and potential relationships between microbial eukaryotes in samples collected from two cold seeps and one trough in the northern South China Sea. SAR (i.e., Stramenopiles, Alveolata, and Rhizaria) was the predominant group in all the samples, and it was highly affiliated to genotypes with potential symbiotic and parasitic strategies identified from other deep-sea extreme environments (e.g., oxygen deficient zones, bathypelagic waters, and hydrothermal vents). Our findings indicated that specialized lineages of deep-sea microbial eukaryotes exist in chemosynthetic cold seeps, where microbial eukaryotes affiliated with parasitic/symbiotic taxa were prevalent in the community. The biogeographic pattern of the total community was best represented by the intermediate operational taxonomic unit (OTU) category, whose relative abundance ranged 0.01–1% within a sample, and the communities of the two cold seeps were distinct from the trough, which suggests that geographical proximity has no critical impact on the distribution of deep-sea microbial eukaryotes. Overall, this study has laid the foundations for future investigations regarding the ecological function and in situ trophic relationships of microbial eukaryotes in deep-sea ecosystems.


Molecules ◽  
2019 ◽  
Vol 24 (19) ◽  
pp. 3441
Author(s):  
Akoumany ◽  
Zykwinska ◽  
Sinquin ◽  
Marchand ◽  
Fanuel ◽  
...  

Bacteria from deep-sea hydrothermal vents constitute an attractive source of bioactive molecules. In particular, exopolysaccharides (EPS) produced by these bacteria become a renewable source of both biocompatible and biodegradable molecules. The low molecular weight (LMW) derivatives of the GY785 EPS produced by the deep-sea hydrothermal vent strain Alteromonas infernus have previously displayed some biological properties, similar to those of glycosaminoglycans (GAG), explored in cancer and tissue engineering. These GAG-mimetic derivatives are obtained through a free radical depolymerization process, which could, however, affect their structural integrity. In a previous study, we have shown that A. infernus produces depolymerizing enzymes active on its own EPS. In the present study, an enzymatic reaction was optimized to generate LMW derivatives of the GY785 EPS, which could advantageously replace the present bioactive derivatives obtained by a chemical process. Analysis by mass spectrometry of the oligosaccharide fractions released after enzymatic treatment revealed that mainly a lyase activity was responsible for the polysaccharide depolymerization. The repeating unit of the GY785 EPS produced by enzyme cleavage was then fully characterized.


2019 ◽  
Vol 85 (22) ◽  
Author(s):  
Kun Zhou ◽  
Rui Zhang ◽  
Jin Sun ◽  
Weipeng Zhang ◽  
Ren-Mao Tian ◽  
...  

ABSTRACT In deep-sea hydrothermal vent environments, sulfur-oxidizing bacteria belonging to the clade SUP05 are crucial symbionts of invertebrate animals. Marine viruses, as the most abundant biological entities in the ocean, play essential roles in regulating the sulfur metabolism of the SUP05 bacteria. To date, vent sponge-associated SUP05 and their phages have not been well documented. The current study analyzed microbiomes of Haplosclerida sponges from hydrothermal vents in the Okinawa Trough and recovered the dominant SUP05 genome, designated VS-SUP05. Phylogenetic analysis showed that VS-SUP05 was closely related to endosymbiotic SUP05 strains from mussels living in deep-sea hydrothermal vent fields. Homology and metabolic pathway comparisons against free-living and symbiotic SUP05 strains revealed that the VS-SUP05 genome shared many features with the deep-sea mussel symbionts. Supporting a potentially symbiotic lifestyle, the VS-SUP05 genome contained genes involved in the synthesis of essential amino acids and cofactors that are desired by the host. Analysis of sponge-associated viral sequences revealed putative VS-SUP05 phages, all of which were double-stranded viruses belonging to the families Myoviridae, Siphoviridae, Podoviridae, and Microviridae. Among the phage sequences, one contig contained metabolic genes (iscR, iscS, and iscU) involved in iron-sulfur cluster formation. Interestingly, genome sequence comparison revealed horizontal transfer of the iscS gene among phages, VS-SUP05, and other symbiotic SUP05 strains, indicating an interaction between marine phages and SUP05 symbionts. Overall, our findings confirm the presence of SUP05 bacteria and their phages in sponges from deep-sea vents and imply a beneficial interaction that allows adaptation of the host sponge to the hydrothermal vent environment. IMPORTANCE Chemosynthetic SUP05 bacteria dominate the microbial communities of deep-sea hydrothermal vents around the world, SUP05 bacteria utilize reduced chemical compounds in vent fluids and commonly form symbioses with invertebrate organisms. This symbiotic relationship could be key to adapting to such unique and extreme environments. Viruses are the most abundant biological entities on the planet and have been identified in hydrothermal vent environments. However, their interactions with the symbiotic microbes of the SUP05 clade, along with their role in the symbiotic system, remain unclear. Here, using metagenomic sequence-based analyses, we determined that bacteriophages may support metabolism in SUP05 bacteria and play a role in the sponge-associated symbiosis system in hydrothermal vent environments.


2018 ◽  
Vol 25 (2) ◽  
pp. 186-207 ◽  
Author(s):  
Georgios Daletos ◽  
Weaam Ebrahim ◽  
Elena Ancheeva ◽  
Mona El-Neketi ◽  
Weiguo Song ◽  
...  

Background: Over the last two decades, deep-sea-derived fungi are considered to be a new source of pharmacologically active secondary metabolites for drug discovery mainly based on the underlying assumption that the uniqueness of the deep sea will give rise to equally unprecedented natural products. Indeed, up to now over 200 new metabolites have been identified from deep-sea fungi, which is in support of the statement made above. Results: This review summarizes the new and/or bioactive compounds reported from deepsea- derived fungi in the last six years (2010 – October 2016) and critically evaluates whether the data published so far really support the notion that these fungi are a promising source of new bioactive chemical entities.


Marine Drugs ◽  
2021 ◽  
Vol 19 (11) ◽  
pp. 642
Author(s):  
Daniela Giordano

Marine organisms are known to produce a wide variety of natural products that are unique in terms of diversity, structural, and functional properties [...]


Sign in / Sign up

Export Citation Format

Share Document