Biochemical characterization and molecular modification of a zearalenone hydrolyzing enzyme Zhd11D from Phialophora attinorum.

ZEN lactone hydrolase (ZHD) can hydrolyze zearalenone (ZEN) to less or non-toxic product, providing an environment-friendly way for food or feeds-containing ZENs detoxification. Here, a newly identified ZHD from Phialophora attinorum, annotated as Zhd11D, was characterized to exhibit highest activity against ZEN at pH 8.0 and 35 â„ƒ with a specific activity of 304.7 U/mg, which was far higher than most of the reported ZHDs. A nonspecific protein engineering method was introduced through fusing a segment of amphiphilic short peptide S1 at the N-terminus of Zhd11D, resulting in both improved activity (1.5-fold) and thermostability (2-fold at 40 â„ƒ). Biochemical analysis demonstrated that self-aggregation caused by intermolecular interactions between S1 contributed to the improvement of the enzymatic properties of Zhd11D. Additionally, S1-Zhd11D showed a higher hydrolysis rate of ZEN than Zhd11D in peanut oil.

Post-translational changes in Phialophora verrucosa via lysine lactylation during prolonged presence in a patient with a CARD9-related immune disorder.

CARD9-related inherited immune disorders are a major risk factor for chronic disseminated fungal infection. In addition to pathogens of Candida and dermatophytes, the environmental opportunists of the black yeast-like fungi are relatively frequent in this patient cohort. Particularly the genus Phialophora is overrepresented. We investigated two isolates of a strain of P. verrucosa residing in a CARD9 patient, sampled with a period of ten years apart. Genomes, melanization and antifungal susceptibility of progenitor and derived strains were compared, and potential adaptation to the host habitat was investigated with proteomic techniques using post-translational modification as a proxy. Global lactylation analysis was performed using high accuracy nano-LC-MS/MS in combination with enrichment of lactylated peptides from digested cell lysates, and subsequent peptide identification. The genome of the derived isolate had accumulated 6945 SNPs, of which 31 were detected in CDS. A large number of identified proteins were significantly enriched, e.g. in melanin biosynthesis. A total of 636 lactylation sites on 420 lactylated proteins were identified, which contained in 26 types of modification motifs. Lysine lactylation (Kla) was found in 23 constituent proteins of the ribosome, indicating an impact of Kla in protein synthesis. Twelve lactylated proteins participated in pathogenicity. A protein-protein interaction (PPI) network analysis suggested that protein lactylations are widely distributed influencing various biological processes. Our findings reveal widespread roles for lysine lactylation in regulating metabolism and melanin biosynthesis in black fungi. Several large rearrangements and inversions were observed in the genome, but genomic changes could not be linked to adaptation or to known clinically relevant properties of progenitor to derived isolate; in vitro antifungal susceptibility had largely remained unaltered.

Phaeohyphomycosis caused by Phialophora americana in a dog.

Phaeohyphomycosis was diagnosed in a 6-year-old, male castrated Dachshund on immunosuppressive treatment. The fungus was identified by culture and PCR as Phialophora americana. This is the first reported case of infection with this pathogen in a dog. The infection was successfully managed medically, without surgical intervention.

Une phaéohyphomycose a été diagnostiquée chez un teckel mâle castré de 6 ans sous traitement immunosuppresseur. Le champignon a été identifié par culture et PCR comme Phialophora americana. Il s'agit du premier cas rapporté d'infection par cet agent pathogène chez un chien. L'infection a été prise en charge médicalement avec succès, sans intervention chirurgicale.

Se diagnosticó feohifomicosis en un macho de Teckel castrado de 6 años en tratamiento inmunosupresor. El hongo fue identificado por cultivo y PCR como Phialophora americana. Este es el primer caso reportado de infección por este patógeno en un perro. La infección se manejó con éxito médicamente, sin intervención quirúrgica.

Feohifomicose foi diagnosticada em um cão da raça Dachshund, macho castrado, de seis anos de idade, em tratamento imunossupressivo. O fungo identificado por cultura e PCR foi Phialophora americana. Este é o primeiro relato de caso de infecção por este patógeno em um cão. A infecção foi bem conduzida com tratamento medicamentoso, sem intervenção cirúrgica.

The global burden of chromoblastomycosis.

BACKGROUND: Chromoblastomycosis (CBM), represents one of the primary implantation mycoses caused by melanized fungi widely found in nature. It is characterized as a Neglected Tropical Disease (NTD) and mainly affects populations living in poverty with significant morbidity, including stigma and discrimination. METHODS AND FINDINGS: In order to estimate the global burden of CBM, we retrospectively reviewed the published literature from 1914 to 2020. Over the 106-year period, a total of 7,740 patients with CBM were identified on all continents except Antarctica. Most of the cases were reported from South America (2,619 cases), followed by Africa (1,875 cases), Central America and Mexico (1,628 cases), Asia (1,390 cases), Oceania (168 cases), Europe (35 cases), and USA and Canada (25 cases). We described 4,022 (81.7%) male and 896 (18.3%) female patients, with the median age of 52.5 years. The average time between the onset of the first lesion and CBM diagnosis was 9.2 years (range between 1 month to 50 years). The main sites involved were the lower limbs (56.7%), followed by the upper limbs (19.9%), head and neck (2.9%), and trunk (2.4%). Itching and pain were reported by 21.5% and 11%, respectively. Malignant transformation was described in 22 cases. A total of 3,817 fungal isolates were cultured, being 3,089 (80.9%) Fonsecaea spp., 552 (14.5%) Cladophialophora spp., and 56 Phialophora spp. (1.5%). CONCLUSIONS AND SIGNIFICANCE: This review represents our current knowledge on the burden of CBM world-wide. The global incidence remains unclear and local epidemiological studies are required to improve these data, especially in Africa, Asia, and Latin America. The recognition of CBM as NTD emphasizes the need for public health efforts to promote support for all local governments interested in developing specific policies and actions for preventing, diagnosing and assisting patients.

Neutrophil Extracellular Traps Serve as Key Effector Molecules in the Protection Against Phialophora verrucosa.

Phialophora verrucosa (P. verrucosa) is a pathogen that can cause chromoblastomycosis and phaeohyphomycosis. Recent evidence suggests that neutrophils can produce neutrophil extracellular traps (NETs) that can protect against invasive pathogens. As such, we herein explored the in vitro functional importance of P. verrucosa-induced NET formation. By assessing the co-localization of neutrophil elastase and DNA, we were able to confirm the formation of classical NETs entrapping P. verrucosa specimens. Sytox Green was then used to stain these NETs following neutrophil infection with P. verrucosa in order to quantify the formation of these extracellular structures. NET formation was induced upon neutrophil exposure to both live, UV-inactivated, and dead P. verrucosa fungi. The ability of these NETs to kill fungal hyphae and conidia was demonstrated through MTT and pouring plate assays, respectively. Overall, our results confirmed that P. verrucosa was able to trigger the production of NETs, suggesting that these extracellular structures may represent an important innate immune effector mechanism controlling physiological responses to P. verrucosa infection, thereby aiding in pathogen control during the acute phases of infection.

Comparative genomics of opportunistic Phialophora species involved in divergent disease types.

BACKGROUND: Black opportunists Phialophora verrucosa complex species can cause different disease types in competent and in immunocompromised individuals, but are remarkably overrepresented in CARD9-related infections. OBJECTIVES: To better understand the ecology and potential pathogenicity of opportunistic Phialophora species and reveal eventual genetic parameters associated with the behaviour in vivo and genetic profiles in patients with CARD9 immunodeficiency. METHODS: Genomes of 26 strains belonging to six species of the Phialophora verrucosa complex were sequenced. Using multilocus analysis, all environmental and clinical strains were identified correctly. We compared the genomes of agents from different disease types among each other including CARD9 immunodeficiency. RESULTS: We obtained genome sizes of the 26 Phialophora strains ranged between 32 and 37 MB. Some species showed considerable intraspecific genomic variation. P americana showed the highest degree of variability. P verrucosa was variable in CAZy enzymes, whereas P americana varied in PKS-related genes. Phialophora species, particularly P verrucosa, are relatively frequent in patients with CARD9-related immunodeficiency. Different mutations in the CARD9 gene seem to increase susceptibility for infection by different groups of species, that is either Candida, dermatophytes or black fungi. A number of patients with chromoblastomycosis revealed an as yet unknown CARD9 mutation. TNFα impairment was prevalent in patients with CARD9 infections, while CBM patients were invariably IFNγ. CONCLUSIONS: From genomic investigations, the known virulence factors between clinical and environmental strains did not reveal any significant difference. Phialophora complex has an equal chance to cause infection in humans, either healthy or CARD9-impaired.

Dark septate endophytes isolated from non-hyperaccumulator plants can increase phytoextraction of Cd and Zn by the hyperaccumulator Noccaea caerulescens.

Dark septate endophytes (DSEs) can improve plant stress tolerance by promoting growth and affecting element accumulation. Due to its ability to accumulate high Cd, Zn, and Ni concentrations in its shoots, Noccaea caerulescens is considered a promising candidate for phytoextraction in the field. However, the ability of DSEs to improve trace element (TE) phytoextraction with N. caerulescens has not yet been studied. The aim of this study was therefore to determine the ability of five DSE strains, previously isolated from poplar roots collected at different TE-contaminated sites, to improve plant development, mineral nutrient status, and metal accumulation by N. caerulescens during a pot experiment using two soils differing in their level of TE contamination. Microscopic observations revealed that the tested DSE strains effectively colonised the roots of N. caerulescens. In the highly contaminated (HC) soil, a threefold increase in root biomass was found in plants inoculated with the Leptodontidium sp. Pr30 strain compared to that in the non-inoculated condition; however, the plant nutrient status was not affected. In contrast, the two strains Phialophora mustea Pr27 and Leptodontidium sp. Me07 had positive effects on the mineral nutrient status of plants without significantly modifying their biomass. Compared to non-inoculated plants cultivated on HC soil, Pr27- and Pr30-inoculated plants extracted more Zn (+ 30%) and Cd (+ 90%), respectively. In conclusion, we demonstrated that the responses of N. caerulescens to DSE inoculation ranged from neutral to beneficial and we identified two strains (i.e. Leptodontidium sp. (Pr30) and Phialophora mustea (Pr27)) isolated from poplar that appeared promising as they increased the amounts of Zn and Cd extracted by improving plant growth and/or TE accumulation by N. caerulescens. These results generate interest in further characterising the DSEs that naturally colonise N. caerulescens and testing their ability to improve phytoextraction.

Phaeohyphomycosis: Cytomorphologic Evaluation in Eleven Cases.

OBJECTIVE: Phaeohyphomycosis caused by phaeoid fungi is a type of mycosis emerging worldwide which causes a wide variety of clinical manifestations. STUDY DESIGN: A retrospective analysis of 11 cases diagnosed with fungal inflammation on cytology over a period of 6 years (2013-2018) was done along with culture/histopathologic confirmation. RESULTS: Of the total of 11 cases, 9 cases presented with subcutaneous swellings and 1 case each with brain and lung lesions. The age range was 30-83 years (mean: 53.6); 8 patients were male and 3 were female. Cytologic smears showed fungal profiles with septate tortuous hyphae, as well as swollen and narrow, yeast-like swellings with an irregular breadth of the hyphae in all cases. The fungal profiles were visualized on a Masson-Fontana stain. The background showed inflammatory cells, giant cells, and necrosis in variable proportions. Five cases were diagnosed as phaeohyphomycosis on cytology, whereas 3 cases were misdiagnosed as aspergillus and 2 as candida. In 1 case, typing of the fungus was not done. Histopathology was available in 5 cases, and in all these a diagnosis of phaeohyphomycosis was reached. Ten of the 11 cases had confirmation on fungal culture. CONCLUSIONS: Phaeoid fungi are rarely seen in routine cytologic practice. Careful evaluation of cytologic smears and an awareness of the characteristic morphologic features of phaeohyphomycosis are helpful in arriving at a correct diagnosis. Fine needle aspiration cytology provides a rapid diagnosis, enabling prompt therapy.

Aspartic peptidase of Phialophora verrucosa as target of HIV peptidase inhibitors: blockage of its enzymatic activity and interference with fungal growth and macrophage interaction.

Phialophora verrucosa causes several fungal human diseases, mainly chromoblastomycosis, which is extremely difficult to treat. Several studies have shown that human immunodeficiency virus peptidase inhibitors (HIV-PIs) are attractive candidates for antifungal therapies. This work focused on studying the action of HIV-PIs on peptidase activity secreted by P. verrucosa and their effects on fungal proliferation and macrophage interaction. We detected a peptidase activity from P. verrucosa able to cleave albumin, sensitive to pepstatin A and HIV-PIs, especially lopinavir, ritonavir and amprenavir, showing for the first time that this fungus secretes aspartic-type peptidase. Furthermore, lopinavir, ritonavir and nelfinavir reduced the fungal growth, causing remarkable ultrastructural alterations. Lopinavir and ritonavir also affected the conidia-macrophage adhesion and macrophage killing. Interestingly, P. verrucosa had its growth inhibited by ritonavir combined with either itraconazole or ketoconazole. Collectively, our results support the antifungal action of HIV-PIs and their relevance as a possible alternative therapy for fungal infections.

Biochemical Characterization and Mutational Analysis of a Lactone Hydrolase from Phialophora americana.

The mycotoxin zearalenone (ZEN) is a secondary metabolite produced mainly by Fusarium species. ZEN poses health hazards both for humans and animals, as a major contaminant in the food and feed industries. Currently, there is no effective technique for degrading ZEN during industrial processes. In this study, we isolated and biochemically characterized a novel lactone hydrolase, ZHD607, isolated from Phialophora americana, cloned, and exogenously expressed in Pichia pastoris. ZHD607 was characterized as a mesophilic lactone hydrolase having a neutral pH and showing optimal activity at 35 °C and pH 8.0. Two mutants, ZHDM1 and I160Y, generated from ZHD607 based on structure and sequence alignment analyses, exhibited 2.9- and 3.4-fold higher activity towards ZEN than did ZHD607. Molecular dynamics simulation revealed diverse mechanisms driving this improved catalytic activity. These findings enrich our knowledge about ZHD enzyme family and represent an important step toward industrialization of ZEN-detoxifying lactone hydrolases.

Phialophora section Catenulatae disassembled: New genera, species, and combinations and a new family encompassing taxa with cleistothecial ascomata and phialidic asexual states.

The Pleuroascaceae (Leotiomycetes) is introduced for Phialophora hyalina (section Catenulatae) and its closest relatives based on analyses of DNA sequences of five gene regions and the comparison of cultural and micromorphological characters. The family is resolved as a strongly supported clade that encompasses Pleuroascus and the new anamorph genera Entimomentora and Venustampulla. The latter includes V. parva, a species placed formerly in Scopulariopsis, and V. echinocandica, which is established for the echinocandin-producing isolate BP-5553. Entimomentora includes E. hyalina, a species based on the ex-type strain of Ph. hyalina. Additional isolates identified as Ph. hyalina are distantly related to the Pleuroacaceae and include Psychrophila antarctica (Arachnopezizaceae) and Cryonesomyces dreyfussii, the sole member of the new genus Cryonesomyces (incertae sedis). Isolates identified or deposited as Ph. alba are also not closely related; they include a species for which we propose the name Neobulgaria koningiana (Gelatinodiscaceae) and a second psychrophilic species that we describe as Psychrophila lagodekhiensis. Of the 13 isolates assessed for in vitro antifungal activity, only V. echinocandica inhibited the growth of Candida albicans.

Phaeohyphomycosis caused by Phialophora americana with CARD9 mutation and 20-year literature review in China.

BACKGROUND: Phaeohyphomycosis is a chronic cutaneous, subcutaneous or systemic mycotic infection caused by various dematiaceous fungi. The diverse clinical manifestations and poor prognosis of phaeohyphomycosis necessitate studies on it to better recognise the disease and improve its management. OBJECTIVES: To investigate the epidemiology, aetiology, diagnosis, treatment and prognosis of phaeohyphomycosis in China over the past 20 years, and to study the first case of phaeohyphomycosis caused by Phialophora americana and the genetic and immunological mechanisms. PATIENTS/METHODS: Clinical and laboratory findings of the case were studied, and the patient's DNA was sequenced for CARD9, followed by immunological studies using patient's PBMCs. Cases of phaeohyphomycosis in China from 1998 to 2018 in both the Chinese and English literature were collected and analysed, including 45 articles and 46 patients. RESULTS: We confirmed the patient holding a homozygous frameshift mutation of CARD9, which led to impairment of pro-inflammatory cytokine production, and lower Th17- and Th22-associated responses upon fungus-specific stimulation. From the literature review, we revealed that the clinical presentations of phaeohyphomycosis were diverse. Diagnoses were established mainly on the basis of histopathology and fungal culture. Oral itraconazole, voriconazole, and posaconazole are the first choices for treatment, and a combination with surgical excision is also recommended. CONCLUSIONS: Our study establishes that obtaining detailed histories is vital for understanding the immune state and that patients with recurrent or chronic phaeohyphomycosis in the absence of known immunodeficiencies should be tested for CARD9 mutations. We hope our findings will aid clinicians in the diagnoses and treatment of such infections.

Case report: Fever- pneumonia- lymphadenectasis- osteolytic- subcutaneous nodule: Disseminated chromoblastomycosis caused by phialophora.

Chromoblastomycosis (CBM) is a chronic cutaneous and subcutaneous fungal infection caused by certain dematiaceous fungi (usually Fonsecaea, Phialophora, or Cladophialophora). Histologically, CBM is characterized by the presence of medlar bodies. However, the diagnosis is difficult because of the rarity of these pathognomonic presentations and the wide variety of presentations. Treatment of these infections is challenging as it lacks standardization. Herein, we report a case of chromoblastomycosis caused by Phialophora, in a 42-year-old immunocompetent male agriculturist from the humid and subtropical region of southern China. He had a 3-month history of pneumonia with intermittent fever, coughing, and expectoration. The infection subsequently spread to the bone and lymph nodes forming deep lesions and eventually resulting in osteolysis and lymphadenectasis. These subcutaneous nodules were observed after 9 months. Antifungal treatment was administered for 20 months leading to clinical improvement before the patient was lost to follow-up. This case is unique because such deep lesions are rare in immunocompetent individuals and because the initial onset was associated with pneumonia.

Melanin: Quantification and protection against oxidative stress in chromoblastomycosis agents.

Chromoblastomycosis (CBM) is a chronic cutaneous and subcutaneous infection caused by melanized fungal species. We quantified the extractable melanin of 77 strains of CBM agents distributed within five genera. Moreover, resistance to oxidative stress was evaluated in strains exposed or not to the melanin inhibitor tricyclazole. The median percentage of melanin mass extracted from dry fungal mass varied from 0.69 (Rhinocladiella similis) to 3.81 (Phialophora americana). Inhibition of melanin synthesis decreased survival rates to hydrogen peroxide. Together, these data highlight the importance of melanin in CBM agents.

Visceral Mycoses in Autopsied Cases in Japan from 1989 to 2013.

BACKGROUND AND METHODS: Our group has continuously studied the epidemiology of visceral mycoses (VM) among autopsy cases in Japan from 1989 to 2013. RESULTS: First, from a total of 11,149 autopsied cases, 571 (5.1%) cases of VM were observed in 2013. It was significantly higher than those of 2005 (p < 0.05) and earlier. Notably, incidence of cases with mucormycetes (Muc) in 2013 was higher than that of 1997 and earlier (p < 0.001), especially in leukemia cases. Muc cases also showed higher rate of "severe infection" compared with other cases (p < .0001). Emerging diseases were also observed. Severe fever with thrombocytopenia syndrome cases showed high incidence of VM as a complication. In addition, we observed cases with the rare mycoses caused by Phialopohra verrucosa and Rhodotorula spp. in our analysis. Moreover, the predominant fungal agent of central nervous system infections changed from Cryptococcus spp. to Aspergillus spp. in 2013. This may be considered a breakthrough infection. CONCLUSION: The prevalence of VM in 2013 became higher than those of 2005 (p < 0.05) and earlier, with a notable increase of incidence in cases with Muc. The occurrence of breakthrough VM and emerging mycoses deserve attention.

Effectiveness of voriconazole and corneal cross-linking on Phialophora verrucosa keratitis: a case report.

BACKGROUND: We report a rare case of Phialophora verrucosa fungal keratitis, which required various types of treatment according to the intractable natural history of the disease. CASE PRESENTATION: A 51-year-old Thai man with poorly controlled diabetes received a bamboo branch injury and developed a perforated corneal lesion on his left eye. A pathological study from therapeutic penetrating keratoplasty showed fungal hyphae. This was later identified as Phialophora verrucosa by polymerase chain reaction. This organism was aggressive and recalcitrant because it relapsed with two corneal grafts and was resistant to amphotericin B, natamycin, and itraconazole. However, we found that the efficacy of voriconazole was promising for treating Phialophora verrucosa. We also used corneal cross-linking to establish corneal integrity after the infection was under control. CONCLUSIONS: Because of the chronic nature of Phialophora verrucosa, a patient's first visit may occur many years after trauma, and sometimes clinical presentation might not appear to indicate fungal infection. Therefore, a high index of suspicion is needed in this situation. Voriconazole showed good results in our case. Instead of using a more invasive keratoplasty, we used corneal cross-linking to strengthen the corneal biomechanics. To the best of our knowledge, this is the first case showing the benefit of corneal cross-linking to improve corneal biomechanics in resolved Phialophora verrucosa keratitis.

Leveraging RNA-Seq to Characterize Resistance to Brown Stem Rot and the Rbs3 Locus in Soybean.

Brown stem rot, caused by the fungus Phialophora gregata, reduces soybean yield by up to 38%. Although three dominant resistance loci have been identified (Rbs1 to Rbs3), the gene networks responsible for pathogen recognition and defense remain unknown. Further, identification and characterization of resistant and susceptible germplasm remains difficult. We conducted RNA-Seq of infected and mock-infected leaf, stem, and root tissues of a resistant (PI 437970, Rbs3) and susceptible (Corsoy 79) genotype. Combining historical mapping data with genotype expression differences allowed us to identify a cluster of receptor-like proteins that are candidates for the Rbs3 resistance gene. Reads mapping to the Rbs3 locus were used to identify potential novel single-nucleotide polymorphisms within candidate genes that could improve phenotyping and breeding efficiency. Comparing responses to infection revealed little overlap in differential gene expression between genotypes or tissues. Gene networks associated with defense, DNA replication, and iron homeostasis are hallmarks of resistance to P. gregata. This novel research demonstrates the utility of combining contrasting genotypes, gene expression, and classical genetic studies to characterize complex disease resistance loci.

Cryo-EM structures of fungal and metazoan mitochondrial calcium uniporters.

The mitochondrial calcium uniporter (MCU) is a highly selective calcium channel and a major route of calcium entry into mitochondria. How the channel catalyses ion permeation and achieves ion selectivity are not well understood, partly because MCU is thought to have a distinct architecture in comparison to other cellular channels. Here we report cryo-electron microscopy reconstructions of MCU channels from zebrafish and Cyphellophora europaea at 8.5 Å and 3.2 Å resolutions, respectively. In contrast to a previous report of pentameric stoichiometry for MCU, both channels are tetramers. The atomic model of C. europaea MCU shows that a conserved WDXXEP signature sequence forms the selectivity filter, in which calcium ions are arranged in single file. Coiled-coil legs connect the pore to N-terminal domains in the mitochondrial matrix. In C. europaea MCU, the N-terminal domains assemble as a dimer of dimers; in zebrafish MCU, they form an asymmetric crescent. The structures define principles that underlie ion permeation and calcium selectivity in this unusual channel.

Monitoring the Chemical Profile in Agarwood Formation within One Year and Speculating on the Biosynthesis of 2-(2-Phenylethyl)Chromones.

Agarwood is highly valued for its uses as incense, perfume, and medicine. However, systematic analyses of dynamic changes of secondary metabolites during the process of agarwood formation have not yet been reported. In this study, agarwood was produced by transfusing the agarwood inducer into the trunk of Aquilaria sinensis, and changing patterns of chemical constituents, especially 2-(2-phenylethyl)chromones (PECs), in wood samples collected from the 1st to 12th month, were analyzed by GC-EI-MS and UPLC-ESI-MS/MS methods. Aromatic compounds, steroids, fatty acids/esters, sesquiterpenoids, and PECs were detected by GC-MS, in which PECs were the major constituents. Following this, UPLC-MS was used for further comprehensive analysis of PECs, from which we found that 2-(2-phenylethyl)chromones of flindersia type (FTPECs) were the most abundant, while PECs with epoxidated chromone moiety were detected with limited numbers and relatively low content. Speculation on the formation of major FTPECs was fully elucidated in our context. The key step of FTPECs biosynthesis is possibly catalyzed by type III polyketide synthases (PKSs) which condensate dihydro-cinnamoyl-CoA analogues and malonyl-CoA with 2-hydroxy-benzoyl-CoA to produce 2-(2-phenyethyl)chromone scaffold, or with 2,5-dihydroxybenzoyl-CoA to form FTPECS with 6-hydroxy group, which may serve as precursors for further reactions catalyzed by hydroxylase or O-methyltransferase (OMT) to produce FTPECs with diverse substitution patterns. It is the first report that systematically analyzed dynamic changes of secondary metabolites during the process of agarwood formation and fully discussed the biosynthetic pathway of PECs.