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1.
Conscious Cogn ; 123: 103727, 2024 Jul 06.
Article in English | MEDLINE | ID: mdl-38972289

ABSTRACT

The intentional binding effect refers to the phenomenon where the perceived temporal interval between a voluntary action and its sensory consequence is subjectively compressed. Prior research revealed the importance of tactile feedback from the keyboard on this effect. Here we examined the necessity of such tactile feedback by utilizing a touch-free key-press device without haptic feedback, and explored how initial/outcome sensory modalities (visual/auditory/tactile) and their consistency influence the intentional binding effect. Participants estimated three delay lengths (250, 550, or 850 ms) between the initial and outcome stimuli. Results showed that regardless of the combinations of sensory modalities between the initial and the outcome stimuli (i.e., modal consistency), the intentional binding effect was only observed in the 250 ms delay condition. This findings indicate a stable intentional binding effect both within and across sensory modalities, supporting the existence of a shared mechanism underlying the binding effect in touch-free voluntary actions.

2.
Neuroimage ; 283: 120425, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-37890562

ABSTRACT

We combined multivariate pattern analysis (MVPA) and electroencephalogram (EEG) to investigate the role of edge, color, and other surface information in the neural representation of visual objects. Participants completed a one-back task in which they were presented with color photographs, grayscale images, and line drawings of animals, tools, and fruits. Our results provide the first neural evidence that line drawings elicit similar neural activities as color photographs and grayscale images during the 175-305 ms window after the stimulus onset. Furthermore, we found that other surface information, rather than color information, facilitates decoding accuracy in the early stages of object representations and affects the speed of this. These results provide new insights into the role of edge-based and surface-based information in the dynamic process of neural representations of visual objects.


Subject(s)
Electroencephalography , Visual Perception , Animals , Humans , Pattern Recognition, Visual , Photic Stimulation/methods
3.
Neuroimage ; 283: 120442, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-37926217

ABSTRACT

The ability of humans to discern facial expressions in a timely manner typically relies on distributed face-selective regions for rapid neural computations. To study the time course in regions of interest for this process, we used magnetoencephalography (MEG) to measure neural responses participants viewed facial expressions depicting seven types of emotions (happiness, sadness, anger, disgust, fear, surprise, and neutral). Analysis of the time-resolved decoding of neural responses in face-selective sources within the inferior parietal cortex (IP-faces), lateral occipital cortex (LO-faces), fusiform gyrus (FG-faces), and posterior superior temporal sulcus (pSTS-faces) revealed that facial expressions were successfully classified starting from ∼100 to 150 ms after stimulus onset. Interestingly, the LO-faces and IP-faces showed greater accuracy than FG-faces and pSTS-faces. To examine the nature of the information processed in these face-selective regions, we entered with facial expression stimuli into a convolutional neural network (CNN) to perform similarity analyses against human neural responses. The results showed that neural responses in the LO-faces and IP-faces, starting ∼100 ms after the stimuli, were more strongly correlated with deep representations of emotional categories than with image level information from the input images. Additionally, we observed a relationship between the behavioral performance and the neural responses in the LO-faces and IP-faces, but not in the FG-faces and lpSTS-faces. Together, these results provided a comprehensive picture of the time course and nature of information involved in facial expression discrimination across multiple face-selective regions, which advances our understanding of how the human brain processes facial expressions.


Subject(s)
Brain Mapping , Facial Expression , Humans , Magnetic Resonance Imaging/methods , Brain/physiology , Emotions/physiology
4.
J Org Chem ; 87(17): 11838-11845, 2022 09 02.
Article in English | MEDLINE | ID: mdl-35981349

ABSTRACT

An efficient approach to functionalized (E)-3-cinnamyl-3-methyl-2,3-dihydrobenzofurans and (E)-(3-methyl-2,3-dihydrobenzofuran-3-yl)but-2-enones has been developed through a Pd-catalyzed one-pot cascade process involving two sequential Heck reactions, that is, an intramolecular Heck reaction of olefin-tethered aryl iodides and an intermolecular Heck reaction with substituted styrenes and α,ß-unsaturated ketones. As a result, a series of desired products were obtained in moderate to good yields and with exclusive E-form selectivities.


Subject(s)
Alkenes , Palladium , Catalysis , Iodides , Styrenes
5.
Org Biomol Chem ; 20(25): 5086-5094, 2022 06 29.
Article in English | MEDLINE | ID: mdl-35698865

ABSTRACT

A catalyzed process for the synthesis of the 4,6-substituted 3,4-dihydro-1,3-oxazin-2-one skeleton has been developed through cycloaddition of in situ generated acyliminium intermediates with alkynes. A range of chain N,O-acetals and terminal alkynes were amenable for this mild transformation. As a result, a series of desired cycloaddition products were obtained in moderate to good yields.


Subject(s)
Alkynes , Skeleton , Catalysis , Cycloaddition Reaction , Ions , Molecular Structure
6.
Perception ; 51(1): 37-50, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34904869

ABSTRACT

Face mask is now a common feature in our social environment. Although face covering reduces our ability to recognize other's face identity and facial expressions, little is known about its impact on the formation of first impressions from faces. In two online experiments, we presented unfamiliar faces displaying neutral expressions with and without face masks, and participants rated the perceived approachableness, trustworthiness, attractiveness, and dominance from each face on a 9-point scale. Their anxiety levels were measured by the State-Trait Anxiety Inventory and Social Interaction Anxiety Scale. In comparison with mask-off condition, wearing face masks (mask-on) significantly increased the perceived approachableness and trustworthiness ratings, but showed little impact on increasing attractiveness or decreasing dominance ratings. Furthermore, both trait and state anxiety scores were negatively correlated with approachableness and trustworthiness ratings in both mask-off and mask-on conditions. Social anxiety scores, on the other hand, were negatively correlated with approachableness but not with trustworthiness ratings. It seems that the presence of a face mask can alter our first impressions of strangers. Although the ratings for approachableness, trustworthiness, attractiveness, and dominance were positively correlated, they appeared to be distinct constructs that were differentially influenced by face coverings and participants' anxiety types and levels.


Subject(s)
Facial Expression , Masks , Anxiety , Attitude , Fear , Humans , Trust
7.
Environ Microbiol ; 23(11): 6940-6952, 2021 11.
Article in English | MEDLINE | ID: mdl-34431210

ABSTRACT

Fungi have been reported to be the dominant eukaryotic group in anoxic sub-seafloor sediments, but how fungi subsist in the anoxic sub-marine sedimental environment is rarely understood. Our previous study demonstrated that the fungus, Schizophyllum commune 20R-7-F01 isolated from a ~2 km sediment below the seafloor, can grow and produce primordia in the complete absence of oxygen with enhanced production of branched-chain amino acids (BCAAs), but the primordia cannot be developed into fruit bodies without oxygen. Here, we present the individual and synergistic effects of oxygen and BCAAs on the fruit-body development of this strain. It was found that the fungus required a minimum oxygen concentration of 0.5% pO2 to generate primordia and 1% pO2 to convert primordia into mature fruit body. However, if BCAAs (20 mM) were added to the medium, the primordium could be developed into fruit body at a lower oxygen concentration up to 0.5% pO2 where genes fst4 and c2h2 playing an important role in compensating oxygen deficiency. Moreover, under hypoxic conditions, the fungus showed an increase in mitochondrial number and initiation of auto-phagocytosis. These findings suggest that the fruit-body formation of S. commune may have multiple mechanisms, including energy and amino acid metabolism in response to oxygen concentrations.


Subject(s)
Schizophyllum , Amino Acids, Branched-Chain , Geologic Sediments , Growth and Development , Oxygen/metabolism , Schizophyllum/metabolism
8.
J Integr Neurosci ; 20(3): 635-644, 2021 Sep 30.
Article in English | MEDLINE | ID: mdl-34645096

ABSTRACT

A reduction in sucrose preference is a key characteristic of depressive-like behaviors after spinal cord injury as judged by the sucrose preference test, the hypothalamic-pituitary-adrenal axis and adult hippocampal neurogenesis. Male rats were divided into three groups: control, sham and spinal cord injury groups. The spinal cord injury rats received a severe mid-thoracic contusion. The Basso, Beattie and Bresnahan score was used to assess motor function. The sucrose preference test and forced swim test were used to evaluate depressive-like behaviors. Serum corticosterone levels were examined by enzyme-linked immunosorbent assay and hippocampal glucocorticoid receptor levels were examined by Western blot to evaluate the function of the hypothalamic-pituitary-adrenal axis. Adult hippocampal neurogenesis was assessed by testing hippocampal brain-derived neurotrophic factor and tropomyosin receptor kinase B levels by Western blot and doublecortin levels by immunohistochemistry. Data showed that spinal cord injury impaired motor function. The spinal cord injury rats exhibited decreased sucrose preference on day six, which continued to decrease until day twelve, followed by a plateau phase. Additionally, the immobility time of the spinal cord injury rats was increased on day thirty-four. Moreover, serum corticosterone levels in the spinal cord injury group peaked on day seven, was decreased by day twenty-one and was increased again on day thirty-five. Serum corticosterone levels were significantly negatively correlated with sucrose preference and positively correlated with immobility time. Finally, hippocampal doublecortin levels on days twenty-one and thirty-five were lower in the spinal cord injury group than in the other groups. These results suggest that hyperactivation of the hypothalamic-pituitary-adrenal axis and the inhibition of adult hippocampal neurogenesis may be part of the underlying mechanism responsible for depressive-like behaviors after spinal cord injury.


Subject(s)
Behavior, Animal/physiology , Depression/physiopathology , Hippocampus/physiopathology , Hypothalamo-Hypophyseal System/metabolism , Neurogenesis/physiology , Spinal Cord Injuries/metabolism , Spinal Cord Injuries/physiopathology , Animals , Disease Models, Animal , Male , Rats , Rats, Sprague-Dawley
9.
Aggress Behav ; 47(2): 226-235, 2021 03.
Article in English | MEDLINE | ID: mdl-33244752

ABSTRACT

Research has consistently demonstrated that faces manipulated to appear more masculine are perceived as more dominant. These studies, however, have used forced-choice paradigms, in which a pair of masculinized and feminized faces was presented side by side. These studies are susceptible to demand characteristics, because participants may be able to draw the conclusion that faces which appear more masculine should be rated as more dominant. To prevent this, we tested if dominance could be perceived when masculinized or feminized faces were presented individually for only 100 ms. We predicted higher dominance ratings to masculinized faces and better memory of them in a surprise recognition memory test. In the experiment, 96 men rated the physical dominance of 40 facial photographs (masculinized = 20, feminized = 20), which were randomly drawn from a larger set of faces. This was followed by a surprise recognition memory test. Half of the participants were assigned to a condition in which the contours of the facial photographs were set to an oval to control for sexual dimorphism in face shape. Overall, men assigned higher dominance ratings to masculinized faces, suggesting that they can appraise differences in facial sexual dimorphism following very brief exposure. This effect occurred regardless of whether the outline of the face was set to an oval, suggesting that masculinized internal facial features were sufficient to affect dominance ratings. However, participants' recognition memory did not differ for masculinized and feminized faces, which could be due to a floor effect.


Subject(s)
Face , Masculinity , Humans , Male , Recognition, Psychology , Sex Characteristics
10.
Org Biomol Chem ; 18(36): 7139-7150, 2020 09 23.
Article in English | MEDLINE | ID: mdl-32966517

ABSTRACT

A new approach to access 1-benzylisoindoline and 1-benzyl-tetrahydroisoquinoline has been developed through nucleophilic addition of organozinc reagents to N,O-acetals. A number of substituted organozinc reagents were amenable for this transformation, and the desired products were obtained with excellent yields. Moreover, Sc(OTf)3 proved to be an effective catalyst for the formation of 1-benzylisoindoline and 1-benzyl-tetrahydroisoquinoline using such nucleophilic addition.

11.
Bioorg Med Chem ; 27(3): 502-515, 2019 02 01.
Article in English | MEDLINE | ID: mdl-30606674

ABSTRACT

Tubulin-targeting drugs have increasingly become the focus of anticancer drugs research. Twenty-five novel benzimidazole grafted benzsulfamide-containing pyrazole ring derivatives were synthesized and evaluated for bioactivity as potential tubulin polymerization inhibitors. Among them, compound 30 showed the most excellent inhibition against tubulin assembly (IC50 = 1.52 µM) and in vitro growth inhibitory activity against a panel of four human cancer cell lines (IC50 = 0.15, 0.21, 0.33 and 0.17 µM, respectively for A549, Hela, HepG2 and MCF-7). It could also validly induce A549 cell apoptosis, cause cell cycle arrest in G2/M phase and disrupt the cellular microtubule network. These results, along with molecular docking data, provided an important basis for further optimization of compound 30 as a potential anticancer agent.


Subject(s)
Antineoplastic Agents/pharmacology , Benzimidazoles/pharmacology , Molecular Docking Simulation , Pyrazoles/pharmacology , Sulfonamides/pharmacology , Tubulin Modulators/pharmacology , Tubulin/metabolism , Animals , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Apoptosis/drug effects , Benzimidazoles/chemical synthesis , Benzimidazoles/chemistry , Cell Cycle Checkpoints/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , HEK293 Cells , Hepatocytes/drug effects , Humans , Mice , Molecular Structure , Polymerization/drug effects , Pyrazoles/chemistry , Structure-Activity Relationship , Sulfonamides/chemistry , Tubulin Modulators/chemical synthesis , Tubulin Modulators/chemistry
12.
Mar Drugs ; 18(1)2019 Dec 20.
Article in English | MEDLINE | ID: mdl-31861953

ABSTRACT

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.


Subject(s)
Fungi/chemistry , Seawater/microbiology , Aquatic Organisms , Biological Products/chemistry
13.
J Vis ; 19(11): 2, 2019 09 03.
Article in English | MEDLINE | ID: mdl-31480073

ABSTRACT

Research has shown that participants can extract the average facial expression from a set of faces when these were presented at fixation. In this study, we investigated whether this performance would be modulated by eccentricity given that neural resources are limited outside the foveal region. We also examined whether or not there would be compulsory averaging in the parafovea as has been previously reported for the orientation of Gabor patches by Parkes, Lund, Angelucci, Solomon, and Morgan (2001). Participants were presented with expressive faces (alone or in sets of nine, at fixation or at 3° to the left or right) and were asked to identify the expression of the central target face or to estimate the average expression of the set. Our results revealed that, although participants were able to extract average facial expressions in central and parafoveal conditions, their performance was superior in the parafovea, suggesting facilitated averaging outside the fovea by peripheral mechanisms. Furthermore, regardless of whether the task was to judge the expression of the central target or set average, participants had a tendency to identify central targets' expressions in the fovea but were compelled to average in the parafovea, a finding consistent with compulsory averaging. The data also supported averaging over substitution models of crowding. We conclude that the ability to extract average expressions in sets of faces and identify single targets' facial expressions is influenced by eccentricity.


Subject(s)
Facial Expression , Facial Recognition/physiology , Adult , Analysis of Variance , Emotions/physiology , Female , Fixation, Ocular/physiology , Fovea Centralis/physiology , Humans , Male , Models, Biological , Orientation/physiology , Young Adult
14.
Environ Microbiol ; 19(2): 803-818, 2017 02.
Article in English | MEDLINE | ID: mdl-28028923

ABSTRACT

Although subseafloor sediments are known to harbour a vast number of microbial cells, the distribution, diversity, and origins of fungal populations remain largely unexplored. In this study, we cultivated fungi from 34 of 47 deep coal-associated sediment samples collected at depths ranging from 1289 to 2457 m below the seafloor (mbsf) off the Shimokita Peninsula, Japan (1118 m water depth). We obtained a total of 69 fungal isolates under strict contamination controls, representing 61 Ascomycota (14 genera, 23 species) and 8 Basidiomycota (4 genera, 4 species). Penicillium and Aspergillus relatives were the most dominant genera within the Ascomycetes, followed by the members of genera Cladosporium, Hamigera, Chaetomium, Eutypella, Acremonium, Aureobasidium, Candida, Eurotium, Exophiala, Nigrospora, Bionectria and Pseudocercosporella. Four Basidiomycota species were identified as genera Schizophyllum, Irpex, Bjerkandera and Termitomyces. Among these isolates, Cladosporium sphaerospermum and Aspergillus sydowii relatives were isolated from a thin lignite coal-sandstone formation at 2457 mbsf. Our results indicate that these cultivable fungal populations are indigenous, originating from past terrigenous environments, which have persisted, possibly as spores, through ∼20 million years of depositional history.


Subject(s)
Coal/microbiology , Fungi/isolation & purification , Geologic Sediments/microbiology , Seawater/microbiology , Fungi/classification , Fungi/genetics , Fungi/growth & development , Japan , Oceans and Seas , Phylogeny
15.
Acta Pharmacol Sin ; 38(9): 1297-1304, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28603287

ABSTRACT

Previous studies have shown that the expression of microRNA-4458 (miR-4458) is dysregulated in hepatocellular carcinoma and colon cancer. In this study, we investigated the direct target of miR-4458 and its biological functions in human lung cancer cells. By using the database TargetScan, we identified Lin28B, an oncogene, as a direct target gene of miR-4458. In dual-luciferase reporter assay, we found that miR-4458 mimics dose-dependently inhibited the luciferase activity of the wild-type 3'UTR of Lin28B in human lung cancer A549 and NCI-H1299 cell lines without affecting its mutant forms, whereas anti-miR-4458, an inhibitor of miR-4458, dose-dependently promoted the luciferase activity of the wild-type 3'UTR of Lin28B in A549 and NCI-H1299 cell lines without affecting its mutant forms. Overexpression of miR-4458 significantly decreased the protein levels of Lin28B in the cells, and inhibited the cell growth and colony formation. Conversely, knockdown of miR-4458 with anti-miR-4458 significantly increased the protein levels of Lin28B, and promoted the cell proliferation, which could be reverted by knockdown of Lin28B expression. In addition, we detected the expression of Lin28B using RT-PCR in 40 human lung cancer tissues and matched peritumoral tissues, and found that Lin28B was overexpressed in lung cancer tissues and negatively correlated with miR-4458 expression (r=-0.694, P<0.05). We conclude that miR-4458 is a tumor suppressor, and Lin28B is the direct target of miR-4458. These results suggest the modulation of miR-4458/Lin28B expression offers a potential therapeutic strategy for lung cancer.


Subject(s)
MicroRNAs/metabolism , RNA-Binding Proteins/antagonists & inhibitors , Cell Proliferation/drug effects , Dose-Response Relationship, Drug , Humans , MicroRNAs/antagonists & inhibitors , MicroRNAs/chemistry , RNA-Binding Proteins/genetics , RNA-Binding Proteins/metabolism , Structure-Activity Relationship , Tumor Cells, Cultured
16.
Psychol Res ; 79(6): 1042-53, 2015 Nov.
Article in English | MEDLINE | ID: mdl-25398479

ABSTRACT

Facial expression is a major source of image variation in face images. Linking numerous expressions to the same face can be a huge challenge for face learning and recognition. It remains largely unknown what level of exposure to this image variation is critical for expression-invariant face recognition. We examined this issue in a recognition memory task, where the number of facial expressions of each face being exposed during a training session was manipulated. Faces were either trained with multiple expressions or a single expression, and they were later tested in either the same or different expressions. We found that recognition performance after learning three emotional expressions had no improvement over learning a single emotional expression (Experiments 1 and 2). However, learning three emotional expressions improved recognition compared to learning a single neutral expression (Experiment 3). These findings reveal both the limitation and the benefit of multiple exposures to variations of emotional expression in achieving expression-invariant face recognition. The transfer of expression training to a new type of expression is likely to depend on a relatively extensive level of training and a certain degree of variation across the types of expressions.


Subject(s)
Attention , Discrimination Learning , Emotions , Facial Expression , Pattern Recognition, Visual , Recognition, Psychology , Adolescent , Adult , Face , Female , Humans , Male , Paired-Associate Learning , Practice, Psychological , Retention, Psychology , Transfer, Psychology , Young Adult
17.
Mar Drugs ; 13(8): 4594-616, 2015 Jul 23.
Article in English | MEDLINE | ID: mdl-26213949

ABSTRACT

Deep-sea fungi, the fungi that inhabit the sea and the sediment at depths of over 1000 m below the surface, have become an important source of industrial, agricultural, and nutraceutical compounds based on their diversities in both structure and function. Since the first study of deep-sea fungi in the Atlantic Ocean at a depth of 4450 m was conducted approximately 50 years ago, hundreds of isolates of deep-sea fungi have been reported based on culture-dependent methods. To date more than 180 bioactive secondary metabolites derived from deep-sea fungi have been documented in the literature. These include compounds with anticancer, antimicrobial, antifungal, antiprotozoal, and antiviral activities. In this review, we summarize the structures and bioactivities of these metabolites to provide help for novel drug development.


Subject(s)
Biological Factors/metabolism , Biological Factors/pharmacology , Fungi/metabolism , Geologic Sediments/microbiology , Seawater/microbiology , Anti-Infective Agents/metabolism , Anti-Infective Agents/pharmacology , Antifungal Agents/metabolism , Antifungal Agents/pharmacology , Antiprotozoal Agents/metabolism , Antiprotozoal Agents/pharmacology , Antiviral Agents/metabolism , Antiviral Agents/pharmacology , Humans , Secondary Metabolism/physiology , Structure-Activity Relationship
18.
Z Naturforsch C J Biosci ; 69(1-2): 53-60, 2014.
Article in English | MEDLINE | ID: mdl-24772823

ABSTRACT

Microcystis and Anabaena are the main cyanobacteria that cause cyanobacterial blooms in Taihu Lake, China. The mechanism of population competition between M. aeruginosa and A. flos-aquae was studied by co-cultivation in the laboratory. The growth of M. aeruginosa was inhibited, while the growth of A. flos-aquae was promoted. The degree of inhibition or promotion was related to the ratio of the initial cell densities. Both cell-free filtrates of A. flos-aquae and co-culture inhibited M. aeruginosa growth, while both cell-free filtrates of M. aeruginosa and co-culture promoted A. flos-aquae growth. Analysis of the cell-free filtrate by gas chromatography-mass spectrometry indicated that M. aeruginosa and A. flos-aquae may secrete some extracellular allelochemicals that inhibit (promote) the growth of M. aeruginosa (A. flos-aquae) in co-culture. These compounds included sulfur compounds, naphthalene derivatives, cedrene derivatives, quinones, phenol derivatives, diphenyl derivatives, anthracene derivatives, and phthalate esters. This study can help to understand the characteristics of M. aeruginosa and A. flos-aquae and to provide new concepts for the control of cyanobacterial blooms in Taihu Lake.


Subject(s)
Anabaena/physiology , Microcystis/physiology , Water Microbiology , Anabaena/growth & development , China , Gas Chromatography-Mass Spectrometry , Microcystis/growth & development , Species Specificity
19.
Psych J ; 13(1): 142-144, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37905919

ABSTRACT

This study examined the impact of an attractive voice compared to an unattractive voice in an economic game. Results showed that proposers with an attractive voice were perceived as more reasonable in their monetary allocations and were less likely to receive punishment for unfair allocation.


Subject(s)
Decision Making , Punishment , Humans
20.
Sci Total Environ ; 933: 173057, 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38729372

ABSTRACT

Dimethylsulfoniopropionate (DMSP), a key organic sulfur compound in marine and subseafloor sediments, is degraded by phytoplankton and bacteria, resulting in the release of the climate-active volatile gas dimethylsulfide (DMS). However, it remains unclear if dominant eukaryotic fungi in subseafloor sediments possess specific abilities and metabolic mechanisms for DMSP degradation and DMS formation. Our study provides the first evidence that fungi from coal-bearing sediments ∼2 km below the seafloor, such as Aspergillus spp., Chaetomium globosum, Cladosporium sphaerospermum, and Penicillium funiculosum, can degrade DMSP and produce DMS. In Aspergillus sydowii 29R-4-F02, which exhibited the highest DMSP-dependent DMS production rate (16.95 pmol/µg protein/min), two DMSP lyase genes, dddP and dddW, were identified. Remarkably, the dddW gene, previously observed only in bacteria, was found to be crucial for fungal DMSP cleavage. These findings not only extend the list of fungi capable of degrading DMSP, but also enhance our understanding of DMSP lyase diversity and the role of fungi in DMSP decomposition in subseafloor sedimentary ecosystems.


Subject(s)
Fungi , Sulfonium Compounds , Sulfonium Compounds/metabolism , Fungi/metabolism , Geologic Sediments/microbiology , Sulfides/metabolism , Biodegradation, Environmental , Carbon-Sulfur Lyases/metabolism
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