Identification and characterization of a fungal cutinase-like enzyme CpCut1 from Cladosporium sp. P7 for polyurethane degradation.

Plastic degradation by biological systems emerges as a prospective avenue for addressing the pressing global concern of plastic waste accumulation. The intricate chemical compositions and diverse structural facets inherent to polyurethanes (PU) substantially increase the complexity associated with PU waste management. Despite the extensive research endeavors spanning over decades, most known enzymes exhibit a propensity for hydrolyzing waterborne PU dispersion (i.e., the commercial Impranil DLN-SD), with only a limited capacity for the degradation of bulky PU materials. Here, we report a novel cutinase (CpCut1) derived from Cladosporium sp. P7, which demonstrates remarkable efficiency in the degrading of various polyester-PU materials. After 12-h incubation at 55°C, CpCut1 was capable of degrading 40.5% and 20.6% of thermoplastic PU film and post-consumer foam, respectively, while achieving complete depolymerization of Impranil DLN-SD. Further analysis of the degradation intermediates suggested that the activity of CpCut1 primarily targeted the ester bonds within the PU soft segments. The versatile performance of CpCut1 against a spectrum of polyester-PU materials positions it as a promising candidate for the bio-recycling of waste plastics.IMPORTANCEPolyurethane (PU) has a complex chemical composition that frequently incorporates a variety of additives, which poses significant obstacles to biodegradability and recyclability. Recent advances have unveiled microbial degradation and enzymatic depolymerization as promising waste PU disposal strategies. In this study, we identified a gene encoding a cutinase from the PU-degrading fungus Cladosporium sp. P7, which allowed the expression, purification, and characterization of the recombinant enzyme CpCut1. Furthermore, this study identified the products derived from the CpCut1 catalyzed PU degradation and proposed its underlying mechanism. These findings highlight the potential of this newly discovered fungal cutinase as a remarkably efficient tool in the degradation of PU materials.

The Genus Cladosporium: A Prospective Producer of Natural Products.

Cladosporium, a genus of ascomycete fungi in the Dematiaceae family, is primarily recognized as a widespread environmental saprotrophic fungus or plant endophyte. Further research has shown that the genus is distributed in various environments, particularly in marine ecosystems, such as coral reefs, mangroves and the polar region. Cladosporium, especially the marine-derived Cladosporium, is a highly resourceful group of fungi whose natural products have garnered attention due to their diverse chemical structures and biological activities, as well as their potential as sources of novel leads to compounds for drug production. This review covers the sources, distribution, bioactivities, biosynthesis and structural characteristics of compounds isolated from Cladosporium in the period between January 2000 and December 2022, and conducts a comparative analysis of the Cladosporium isolated compounds derived from marine and terrestrial sources. Our results reveal that 34% of Cladosporium-derived natural products are reported for the first time. And 71.79% of the first reported compounds were isolated from marine-derived Cladosporium. Cladosporium-derived compounds exhibit diverse skeletal chemical structures, concentrating in the categories of polyketides (48.47%), alkaloids (19.21%), steroids and terpenoids (17.03%). Over half of the natural products isolated from Cladosporium have been found to have various biological activities, including cytotoxic, antibacterial, antiviral, antifungal and enzyme-inhibitory activities. These findings testify to the tremendous potential of Cladosporium, especially the marine-derived Cladosporium, to yield novel bioactive natural products, providing a structural foundation for the development of new drugs.

A new indole alkaloid from Cladosporium sp. SCSIO41205.

A new indole compound, N-hydroxy-N-(2-(1-hydroxy-2-methoxy-1H-indol-3-yl)ethyl acetamide (1), together with four known compounds, N-(2-(1H-indol-3-yl)ethylacetamide (2), N-acetylamicoumacin C (3), N-(2-phenylethyl)acetamide (4), and (2 R,3S)-1-(4-hydroxyphenyl)butane-2,3-diol (5) were isolated from Cladosporium sp. SCSIO41205. Their structures were established by detailed analysis of the NMR and HR-ESI-MS data.

Biodegradation of Low Density Polyethylene by the Fungus Cladosporium sp. Recovered from a Landfill Site.

Low density polyethylene (LDPE) has been widely used commercially for decades; however, as a non-degradable material, its continuous accumulation has contributed to serious environmental issues. A fungal strain, Cladosporium sp. CPEF-6 exhibiting a significant growth advantage on MSM-LDPE (minimal salt medium), was isolated and selected for biodegradation analysis. LDPE biodegradation was analyzed by weight loss percent, change in pH during fungal growth, environmental scanning electron microscopy (ESEM), and Fourier transformed infrared spectroscopy (FTIR). Inoculation with the strain Cladosporium sp. CPEF-6 resulted in a 0.30 ± 0.06% decrease in the weight of untreated LDPE (U-LDPE). After heat treatment (T-LDPE), the weight loss of LDPE increased significantly and reached 0.43 ± 0.01% after 30 days of culture. The pH of the medium was measured during LDPE degradation to assess the environmental changes caused by enzymes and organic acids secreted by the fungus. The fungal degradation of LDPE sheets was characterized by ESEM analysis of topographical alterations, such as cracks, pits, voids, and roughness. FTIR analysis of U-LDPE and T-LDPE revealed the appearance of novel functional groups associated with hydrocarbon biodegradation as well as changes in the polymer carbon chain, confirming the depolymerization of LDPE. This is the first report demonstrating the capacity of Cladosporium sp. to degrade LDPE, with the expectation that this finding can be used to ameliorate the negative impact of plastics on the environment.

Current Status and Future Prospects of Cladosporium sp., a Biocontrol Agent for Sustainable Plant Protection.

The fungal biocontrol agents, Cladosporium sp. have great economic importance on account of their beneficial effects on the integrated pest management (IPM) program. The different species of this genus can control different arthropod pests like sweetpotato whitefly, sugarcane woolly aphid, two-spotted mite, cotton aphid, cotton leaf worm, red spider mite, armyworm; and different plant diseases like- rice blast, wheat stripe rust, chrysanthemum white rust, etc. Chemical pesticides are a common practice by the user to protect their crops from these pests. But the intensive use of chemical pesticides has harmful impacts on human health and ecosystem functioning, and they also reduce plant protection sustainability. Sustainable plant protection could be achieved through the reduction of chemical pesticides, resulting in minimal impact on the environment without compromising crop yields. This review was written based on biocontrol methods using Cladosporium sp. which is an alternative option for pest management. Continued research concerning the commercialization of these biocontrol agents as biopesticides may contribute to sustainable plant protection.

Plant Growth Promotion by Two Volatile Organic Compounds Emitted From the Fungus Cladosporium halotolerans NGPF1.

Microbial volatiles have beneficial roles in the agricultural ecological system, enhancing plant growth and inducing systemic resistance against plant pathogens without being hazardous to the environment. The interactions of plant and fungal volatiles have been extensively studied, but there is limited research specifically elucidating the effects of distinct volatile organic compounds (VOCs) on plant growth promotion. The current study was conducted to investigate the impact of VOCs from Cladosporium halotolerans NGPF1 on plant growth, and to elucidate the mechanisms for the plant growth-promoting (PGP) activity of these VOCs. The VOCs from C. halotolerans NGPF1 significantly promoted plant growth compared with the control, and this PGP activity of the VOCs was culture medium-dependent. Headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS) identified two VOC structures with profiles that differed depending on the culture medium. The two compounds that were only produced in potato dextrose (PD) medium were identified as 2-methyl-butanal and 3-methyl-butanal, and both modulated plant growth promotion and root system development. The PGP effects of the identified synthetic compounds were analyzed individually and in blends using N. benthamiana plants. A blend of the two VOCs enhanced growth promotion and root system development compared with the individual compounds. Furthermore, real-time PCR revealed markedly increased expression of genes involved in auxin, expansin, and gibberellin biosynthesis and metabolism in plant leaves exposed to the two volatile blends, while cytokinin and ethylene expression levels were decreased or similar in comparison with the control. These findings demonstrate that naturally occurring fungal VOCs can induce plant growth promotion and provide new insights into the mechanism of PGP activity. The application of stimulatory volatiles for growth enhancement could be used in the agricultural industry to increase crop yield.

Bioactive cyclohexene derivatives from a mangrove-derived fungus Cladosporium sp. JJM22.

Four new cyclohexene derivatives cladoscyclitols A-D (1-4) and one new ribofuranose phenol derivative 4-O-α-D-ribofuranose-2-pentyl-3-phemethylol (5) were obtained from the EtOAC extract of the mangrove-derived endophytic fungus Cladosporium sp. JJM22. The structures were elucidated by extensive NMR and MS analysis, while the absolute configurations of the stereogenic carbons were established based on quantum-chemical electronic circular dichroism calculations or comparison of the optical rotations with those of related compounds. Compounds 2 and 5 displayed potent inhibitory activity against α-glucosidase with the IC50 values of 2.95 and 2.05 µM, respectively.

Cladosporine A, a new indole diterpenoid alkaloid with antimicrobial activities from Cladosporium sp.

Cladosporine A (1), a new indole diterpenoid alkaloid, was isolated from the extract of a fungal strain Cladosporium sp. JNU17DTH12-9-01. Its structure was elucidated by extensive spectroscopic analysis, and the absolute configurations were determined by electronic circular dichroism (ECD) experiments. This is the first report of the presence of indole diterpenoid alkaloid in the genus Cladosporium. The antimicrobial activities against Staphylococcus aureus 209P, Escherichia coli ATCC0111, Aspergillus niger R330, and Candida albicans FIM709 were evaluated. Compound 1 showed MICs of 4 µg/mL and 16 µg/mL against S. aureus 209P and C. albicans FIM709, respectively.

Metabolites From the Mangrove-Derived Fungus Cladosporium sp. HNWSW-1.

Two new benzoic acids, cladoslide A (1) and cladoslide B (2); one new ß-carboline derivative, cladospomine (3); and one new pyridin-2(1H)-one, cladoslide C (4), were isolated from the fermentation cultures of the mangrove-derived fungus Cladosporium sp. HNWSW-1, along with the previously reported N-acetyl-ß-oxotryptamine (5), (4S,5S,11R)-iso-cladospolide B (6), (4S,5S,11S)-iso-cladospolide B (7), and (4R,5S,11R)-iso-cladospolide B (8). Their structures were elucidated by spectroscopic analysis, Rh2(OCOCF3)4-induced ECD experiments, and Marfey's method. Compound 1 showed cytotoxicity against the K562 cell line with IC50 values of 13.10 ± 0.08 µM. Moreover, compounds 1 and 5 exhibited inhibitory activity against α-glycosidase with IC50 values of 0.32 ± 0.01 mM and 0.17 ± 0.01 mM, respectively.

Cladodionen Is a Potential Quorum Sensing Inhibitor Against Pseudomonas aeruginosa.

Pseudomonas aeruginosa is an opportunistic pathogen using virulence factors and biofilm regulated by quorum sensing (QS) systems to infect patients and protect itself from environmental stress and antibiotics. Interfering with QS systems is a novel approach to combat P. aeruginosa infections without killing the bacteria, meaning that it is much harder for bacteria to develop drug resistance. A marine fungus Cladosporium sp. Z148 with anti-QS activity was obtained from Jiaozhou Bay, China. Cladodionen, a novel QS inhibitor, was isolated from the extracts of this fungus. Cladodionen had a better inhibitory effect than pyocyanin on the production of elastase and rhamnolipid. It also inhibited biofilm formation and motilities. The mRNA expressions of QS-related genes, including receptor proteins (lasR, rhlR and pqsR), autoinducer synthases (lasI, rhlI and pqsA) and virulence factors (lasB and rhlA) were down-regulated by cladodionen. Molecular docking analysis showed that cladodionen had better binding affinity to LasR and PqsR than natural ligands. Moreover, the binding affinity of cladodionen to LasR was higher than to PqsR. Cladodionen exhibits potential as a QS inhibitor against P. aeruginosa, and its structure-activity relationships should be further studied to illustrate the mode of action, optimize its structure and improve anti-QS activity.

Altertoxins with Quorum Sensing Inhibitory Activities from The Marine-Derived Fungus Cladosporium sp. KFD33.

Five new perylenequinone derivatives, altertoxins VIII-XII (1-5), as well as one known compound cladosporol I (6), were isolated from the fermentation broth of the marine-derived fungus Cladosporium sp. KFD33 from a blood cockle from Haikou Bay, China. Their structures were determined based on spectroscopic methods and ECD spectra analysis along with quantum ECD calculations. Compounds 1-6 exhibited quorum sensing inhibitory activities against Chromobacterium violaceum CV026 with MIC values of 30, 30, 20, 30, 20 and 30 µg/well, respectively.

New citrinin derivatives from the deep-sea-derived fungus Cladosporium sp. SCSIO z015.

During the course of our search for novel bioactive compounds from marine fungi, four new citrinin derivatives, cladosporins A-D (1-4) were isolated from a culture broth of the deep-sea-derived fungus Cladosporium sp. SCSIO z015. Their complete structural assignments were elucidated by the extensive spectroscopic investigation. The absolute configurations of 1-3 were established by quantum chemical calculations of the electronic circular dichroism (ECD) spectra. Compounds 1-4 showed weak toxicity towards brine shrine naupalii with LC50 values of 72.0, 81.7, 49.9 and 81.4 µM, respectively. And 4 also showed significant antioxidant activity against ɑ,α-diphenyl-picrylhydrazyl (DPPH) radicals with an IC50 value of 16.4 µM.

Two New Succinimide Derivatives Cladosporitins A and B from the Mangrove-derived Fungus Cladosporium sp. HNWSW-1.

Two new succinimide-containing derivatives, cladosporitins A (1) and B (2), were isolated from the fermentation cultures of the mangrove-derived fungus Cladosporium sp. HNWSW-1, along with a new pyrone, clapone (3), as well as the previously reported talaroconvolutin A (4) and anthraquinone (5). The structures of the isolated compounds were elucidated by 1D, 2D NMR, and HRMS spectral analysis. Compound 2 showed cytotoxicity against BEL-7042, K562 and SGC-7901 cell lines with IC50 values of 29.4 ± 0.35 µM, 25.6 ± 0.47 µM, and 41.7 ± 0.71 µM, respectively, whereas compound 4 exhibited cytotoxicity against Hela and BEL-7042 cell lines with IC50 values of 14.9 ± 0.21 µM and 26.7 ± 1.1 µM, respectively. In addition, compounds 4 and 5 displayed inhibitory activity against α-glycosidase, with IC50 values of 78.2 ± 2.1 µM and 49.3 ± 10.6 µM, respectively.

Polyketides From the Endophytic Fungus Cladosporium sp. Isolated From the Mangrove Plant Excoecaria agallocha.

Five new polyketides (2-6) and ten known compounds (1 and 7-15) were obtained from the fermentation products of the endophytic fungus Cladosporium sp. OUCMDZ-302 with the mangrove plant, Excoecaria agallocha (Euphorbiaceae). The new structures of 2-6 were established on the basis of ECD, specific rotation and spectroscopic data as well as the chemical calculation. Compound 7 showed cytotoxicity against H1975 cell line with an IC50 value of 10.0 µM. Compounds 4 and 8-10 showed radical scavenging activity against DPPH with the IC50 values of 2.65, 0.24, 5.66, and 6.67 µM, respectively. In addition, the absolute configuration of compound 1 was solidly determined by X-ray and sugar analysis of the acidic hydrolysates for the first time as well as those of compounds 8-10 in this paper.

Optical Sensing for Evaluating the Severity of Disease Caused by Cladosporium sp. in Barley under Warmer Conditions.

Crop yield is critically related to the physiological responses and disease resistance of the crop, which could be strongly affected by high temperature conditions. We observed the changes in the growth of barley under higher than ambient air-temperature conditions using a temperature gradient field chamber (TGFC) during winter and spring. Before the stem extension stage of barley growth, Cladosporium sp. spontaneously appeared in the TGFC. The severity of disease became serious under warmer temperature conditions. Further, the stomata closed as the severity of the disease increased; however, stomatal conductance at the initial stage of disease was higher than that of the normal leaves. This was likely due to the Iwanov effect, which explains that stressed plants rapidly and transiently open their stomata before longer-term closure. In this study, we tested three optical methods: soil-plant analysis development (SPAD) chlorophyll index, photochemical reflectance index (PRI), and maximum quantum yield (Fv/Fm). These rapid evaluation methods have not been used in studies focusing on disease stress, although some studies have used these methods to monitor other stresses. These three indicative parameters revealed that diseased barley exhibited lower values of these parameters than normal, and with the increase in disease severity, these values declined further. Our results will be useful in efficient monitoring and evaluation of crop diseases under future warming conditions.

Cladosporamide A, a new protein tyrosine phosphatase 1B inhibitor, produced by an Indonesian marine sponge-derived Cladosporium sp.

Cladosporamide A (1), a new protein tyrosine phosphatase (PTP) 1B inhibitor, was isolated together with a known prenylated flavanone derivative (2) from the culture broth of an Indonesian marine sponge-derived Cladosporium sp. TPU1507 by solvent extraction, ODS column chromatography, and preparative HPLC (ODS). The structure of 1 was elucidated based on 1D and 2D NMR data. Compound 1 modestly inhibited PTP1B and T-cell PTP (TCPTP) activities with IC50 values of 48 and 54 µM, respectively. The inhibitory activity of 2 against PTP1B (IC50 = 11 µM) was approximately 2-fold stronger than that against TCPTP (IC50 = 27 µM).

Cladodionen, a Cytotoxic Hybrid Polyketide from the Marine-Derived Cladosporium sp. OUCMDZ-1635.

A new hybrid polyketide, cladodionen (1), together with a new abscisic acid analogue, cladosacid (2), were isolated from the marine-derived fungus, Cladosporium sp. OUCMDZ-1635. Their structures, including the absolute configurations, were fully elucidated on the basis of spectroscopic analysis, ECD spectra, quantum chemical calculations, and chemical methods. Cladodionen (1) showed cytotoxic activities against MCF-7, HeLa, HCT-116, and HL-60 human cancer cell lines with IC50 values of 18.7, 19.1, 17.9, and 9.1 µM.

Three new highly oxygenated sterols and one new dihydroisocoumarin from the marine sponge-derived fungus Cladosporium sp. SCSIO41007.

Three new highly oxygenated sterols (1-3) and a new dihydroisocoumarin (7) together with six known compounds were isolated from the extracts of the culture of a sponge-derived fungus Cladosporium sp. SCSIO41007. The structures of all new compounds (1-3, 7) were determined by the extensive spectroscopic analysis including NMR, MS, IR, and UV. Their absolute configurations were determined by X-ray single-crystal and CD data analysis. Compound 2 exhibited weak inhibitory activity against H3N2 with the IC50 value of 16.2 µM.

Mycotic pseudoaneurysm of a pulmonary artery branch caused by Cladosporium.

We report the case of a 53-year-old male with a history of acute myelogenous leukemia, who suffered the rupturing of a right-sided pulmonary artery pseudoaneurysm combined with pneumonia. He underwent a right-sided lower lobectomy. The resected lung tissue demonstrated a mycotic pseudoaneurysm of a pulmonary artery branch together with a filamentous fungal infection. Pseudoaneurysms are caused by the breaching of all layers of a blood vessel wall. The extravasated blood is trapped by the surrounding extravascular tissue or clots. Cladosporium was detected during a polymerase chain reaction-based analysis followed by DNA sequencing of formalin-fixed paraffin-embedded lung tissue samples. Although previous cases of pulmonary artery pseudoaneurysms caused by fungal infections, e.g., Candida or Aspergillus sp., have been reported, to the best of our knowledge this is the first case to involve cladosporiosis.

A new antiviral pregnane from a gorgonian-derived Cladosporium sp. fungus.

A new pregnane, 3α-hydroxy-7-ene-6,20-dione (1), and five known steroids (2-6), along with one known steroidal glycoside (7) were obtained from the fungus Cladosporium sp. WZ-2008-0042 cultured from a gorgonian Dichotella gemmacea collected from the South China Sea. The structure and absolute configuration of the new compound (1) were elucidated by comprehensive spectroscopic data and X-ray diffraction data. The compound has a rare configuration of 3α-OH that is different from most of pregnanes. All of the isolated compounds were evaluated for their antiviral activities against respiratory syncytial virus (RSV). Among them, 1 exhibited potential antiviral activity with the IC50 value of 0.12 mM.