Six New Antimicrobial Metabolites from the Deep-Sea Sediment-Derived Fungus Aspergillus fumigatus SD-406

Six new metabolites, including a pair of inseparable mixtures of secofumitremorgins A (1a) and B (1b), which differed in the configuration of the nitrogen atom, 29-hydroxyfumiquinazoline C (6), 10R-15-methylpseurotin A (7), 1,4,23-trihydroxy-hopane-22,30-diol (10), and sphingofungin I (11), together with six known compounds (2–5 and 8–9), were isolated and identified from the deep-sea sediment-derived fungus Aspergillus fumigatus SD-406. Their structures were determined by detailed spectroscopic analysis of NMR and MS data, chiral HPLC analysis of the acidic hydrolysate, X-ray crystallographic analysis, J-based configuration analysis, and quantum chemical calculations of ECD, OR, and NMR (with DP4+ probability analysis). Among the compounds, 1a/1b represent a pair of novel scaffolds derived from indole diketopiperazine by cleavage of the amide bond following aromatization to give a pyridine ring. Compounds 1, 4, 6, 7, 10 and 11 showed inhibitory activities against pathogenic bacteria and plant pathogenic fungus, with MIC values ranging from 4 to 64 μg/mL.

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Antimicrobial Sesquiterpenoid Derivatives and Monoterpenoids from the Deep-Sea Sediment-Derived Fungus Aspergillus versicolor SD-330

Marine Drugs ◽

10.3390/md17100563 ◽

2019 ◽

Vol 17 (10) ◽

pp. 563 ◽

Cited By ~ 6

Author(s):

Xiao-Dong Li ◽

Xiao-Ming Li ◽

Xiu-Li Yin ◽

Xin Li ◽

Bin-Gui Wang

Keyword(s):

Deep Sea ◽

Pathogenic Bacteria ◽

Vibrio Anguillarum ◽

Antimicrobial Activities ◽

Crystallographic Analysis ◽

Edwardsiella Tarda ◽

Aspergillus Versicolor ◽

Deep Sea Sediment ◽

X Ray ◽

The Absolute

Two new antimicrobial bisabolane-type sesquiterpenoid derivatives, ent-aspergoterpenin C (compound 1) and 7-O-methylhydroxysydonic acid (2), and two new butyrolactone-type monoterpenoids, pestalotiolactones C (3) and D (4), along with a known monoterpenoid pestalotiolactone A (5) and four known bisabolane sesquiterpenoids (6−9), were isolated and identified from the deep-sea sediment-derived fungus Aspergillus versicolor SD-330. The structures of these compounds were elucidated on the basis of spectroscopic analysis, and the absolute configurations of the new compounds 1−4 were determined by the combination of NOESY and TDDFT-ECD calculations and X-ray crystallographic analysis. Additionally, we first determined and reported the absolute configuration of the known monoterpenoid pestalotiolactone A (5) through the X-ray crystallographic experiment. All of these isolated compounds were evaluated for antimicrobial activities against human and aquatic pathogenic bacteria. Compounds 1, 2, 6 and 9 exhibited selective inhibitory activities against zoonotic pathogenic bacteria such as Escherichia coli, Edwardsiella tarda, Vibrio anguillarum and V. harveyi, with MIC values ranging from 1.0 to 8.0 μg/mL.

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20-Nor-Isopimarane Epimers Produced by Aspergillus wentii SD-310, a Fungal Strain Obtained from Deep Sea Sediment

Marine Drugs ◽

10.3390/md16110440 ◽

2018 ◽

Vol 16 (11) ◽

pp. 440 ◽

Cited By ~ 7

Author(s):

Xiao-Dong Li ◽

Xin Li ◽

Xiao-Ming Li ◽

Gang-Ming Xu ◽

Yang Liu ◽

...

Keyword(s):

Deep Sea ◽

Density Functional ◽

Pathogenic Bacteria ◽

Pathogenic Fungi ◽

Antimicrobial Activities ◽

Crystallographic Analysis ◽

Edwardsiella Tarda ◽

Separation And Purification ◽

Deep Sea Sediment ◽

Aspergillus Wentii

Four new uncommon 20-nor-isopimarane diterpenoid epimers, aspewentins I−L (1–4), together with a new methylated derivative of 3, aspewentin M (5), were isolated from the deep sea sediment-derived fungus Aspergillus wentii SD-310. The very similar structures of these epimers made the separation and purification procedures difficult. The structures of compounds 1–5 were illustrated based on spectroscopic analysis, and the absolute configurations of compounds 1–5 were unambiguously determined by the combination of NOESY, time-dependent density functional (TDDFT)-ECD calculations, and X-ray crystallographic analysis. These metabolites represented the rare examples of 20-nor-isopimarane analogues possessing a cyclohexa-2,5-dien-1-one moiety. These compounds were tested for antimicrobial activities against human and aquatic pathogenic bacteria, as well as plant-pathogenic fungi. While compounds 1 and 2 exhibited inhibitory activities against zoonotic pathogenic bacteria such as Escherichia coli, Edwardsiella tarda, Vibrio harveyi, and V. parahaemolyticus, compound 5 showed potent activity against the plant pathogen Fusarium graminearum.

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The novel metallo-β-lactamase PNGM-1 from a deep-sea sediment metagenome: crystallization and X-ray crystallographic analysis

Acta Crystallographica Section F Structural Biology Communications ◽

10.1107/s2053230x18012268 ◽

2018 ◽

Vol 74 (10) ◽

pp. 644-649 ◽

Cited By ~ 3

Author(s):

Kwang Seung Park ◽

Myoung-Ki Hong ◽

Jin Wan Jeon ◽

Ji Hwan Kim ◽

Jeong Ho Jeon ◽

...

Keyword(s):

Deep Sea ◽

Metagenomic Library ◽

Crystallographic Analysis ◽

Monoclinic Space Group ◽

The Novel ◽

Unit Cell Parameters ◽

Deep Sea Sediment ◽

X Ray ◽

Cell Parameters ◽

Great Health

Metallo-β-lactamases (MBLs) are present in major Gram-negative pathogens and environmental species, and pose great health risks because of their ability to hydrolyze the β-lactam rings of antibiotics such as carbapenems. PNGM-1 was the first reported case of a subclass B3 MBL protein that was identified from a metagenomic library from deep-sea sediments that predate the antibiotic era. In this study, PNGM-1 was overexpressed, purified and crystallized. Crystals of native and selenomethionine-substituted PNGM-1 diffracted to 2.10 and 2.30 Å resolution, respectively. Both the native and the selenomethionine-labelled PNGM-1 crystals belonged to the monoclinic space group P21, with unit-cell parameters a = 122, b = 83, c = 163 Å, β = 110°. Matthews coefficient (V M) calculations suggested the presence of 6–10 molecules in the asymmetric unit, corresponding to a solvent content of ∼31–58%. Structure determination is currently in progress.

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Novel Harziane Diterpenes from Deep-Sea Sediment Fungus Trichoderma sp. SCSIOW21 and Their Potential Anti-Inflammatory Effects

Marine Drugs ◽

10.3390/md19120689 ◽

2021 ◽

Vol 19 (12) ◽

pp. 689

Author(s):

Hongxu Li ◽

Xinyi Liu ◽

Xiaofan Li ◽

Zhangli Hu ◽

Liyan Wang

Keyword(s):

Deep Sea ◽

2D Nmr ◽

Crystallographic Analysis ◽

Spectroscopic Methods ◽

2D Nmr Spectroscopy ◽

Deep Sea Sediment ◽

X Ray ◽

Trichoderma Sp ◽

Anti Inflammatory ◽

Inflammatory Effect

Five undescribed harziane-type diterpene derivatives, namely harzianol K (1), harzianol L (4), harzianol M (5), harzianol N (6), harzianol O (7), along with two known compounds, hazianol J (2) and harzianol A (3) were isolated from the deep-sea sediment-derived fungus Trichoderma sp. SCSIOW21. The relative configurations were determined by meticulous spectroscopic methods including 1D, 2D NMR spectroscopy, and HR-ESI-MS. The absolute configurations were established by the ECD curve calculations and the X-ray crystallographic analysis. These compounds (1, and 4–7) contributed to increasing the diversity of the caged harziane type diterpenes with highly congested skeleton characteristics. Harzianol J (2) exhibited a weak anti-inflammatory effect with 81.8% NO inhibition at 100 µM.

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Alcanivorax profundimaris sp. nov., a Novel Marine Hydrocarbonoclastic Bacterium Isolated from Seawater and Deep-Sea Sediment

Current Microbiology ◽

10.1007/s00284-020-02322-7 ◽

2021 ◽

Vol 78 (3) ◽

pp. 1053-1060

Author(s):

Chunming Dong ◽

Qiliang Lai ◽

Xiupian Liu ◽

Li Gu ◽

Yu Zhang ◽

...

Keyword(s):

Deep Sea ◽

Deep Sea Sediment

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Characterization of the mbsA Gene Encoding a Putative APSES Transcription Factor in Aspergillus fumigatus

International Journal of Molecular Sciences ◽

10.3390/ijms22073777 ◽

2021 ◽

Vol 22 (7) ◽

pp. 3777

Author(s):

Yong-Ho Choi ◽

Sang-Cheol Jun ◽

Min-Woo Lee ◽

Jae-Hyuk Yu ◽

Kwang-Soo Shin

Keyword(s):

Aspergillus Fumigatus ◽

Pathogenic Fungus ◽

Hyphal Growth ◽

Spore Wall ◽

Mrna Levels ◽

Chitin Synthesis ◽

Helix Loop Helix ◽

Growth Development ◽

Opportunistic Pathogenic

The APSES family proteins are transcription factors (TFs) with a basic helix-loop-helix domain, known to regulate growth, development, secondary metabolism, and other biological processes in Aspergillus species. In the genome of the human opportunistic pathogenic fungus Aspergillus fumigatus, five genes predicted to encode APSES TFs are present. Here, we report the characterization of one of these genes, called mbsA (Afu7g05620). The deletion (Δ) of mbsA resulted in significantly decreased hyphal growth and asexual sporulation (conidiation), and lowered mRNA levels of the key conidiation genes abaA, brlA, and wetA. Moreover, ΔmbsA resulted in reduced spore germination rates, elevated sensitivity toward Nikkomycin Z, and significantly lowered transcripts levels of genes associated with chitin synthesis. The mbsA deletion also resulted in significantly reduced levels of proteins and transcripts of genes associated with the SakA MAP kinase pathway. Importantly, the cell wall hydrophobicity and architecture of the ΔmbsA asexual spores (conidia) were altered, notably lacking the rodlet layer on the surface of the ΔmbsA conidium. Comparative transcriptomic analyses revealed that the ΔmbsA mutant showed higher mRNA levels of gliotoxin (GT) biosynthetic genes, which was corroborated by elevated levels of GT production in the mutant. While the ΔmbsA mutant produced higher amount of GT, ΔmbsA strains showed reduced virulence in the murine model, likely due to the defective spore integrity. In summary, the putative APSES TF MbsA plays a multiple role in governing growth, development, spore wall architecture, GT production, and virulence, which may be associated with the attenuated SakA signaling pathway.

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