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The bacterial wilt caused by Ralstonia solanacearum seriously affects crop yield and safety and is difficult to control. Biological activity-guided screening led to the isolation of 11 phenolic compounds including three undescribed compounds (carnemycin H-I and stromemycin B) from the secondary metabolites of a marine-derived Aspergillus ustus . One new compound is an unusual phenolic dimer. Their structures were elucidated by comprehensive spectroscopic data and J -based configurational analysis. The antibacterial activities of the isolated compounds against R. solanacearum were evaluated. Compound 3 exhibited excellent inhibitory activity with an MIC value of 3 μg/mL, which was comparable to that of streptomycin sulfate. Additionally, 3 significantly changed the morphology and inhibited the activity of succinate dehydrogenase (SDH) to interfere with the growth of R. solanacearum . Molecular docking was conducted to clarify the potential mechanisms of compound 3 with SDH. Further in vivo experiments demonstrated that 3 could remarkably inhibit the occurrence of bacterial wilt on tomatoes.

Four new drimane sesquiterpenoids ( 1 - 4 ) and three known ones ( 5 - 7 ) were isolated from the fermentation broth of the mangrove-derived Aspergillus ustus 094102. Compound 5 was further resolved as four purified compounds 5a - 5d . By means of extensive spectroscopic and ECD analysis as well as the chemical transformation, their structures were identified as (2 R ,3 R ,5 S ,9 R ,10 S )-2,3,9,11-tetrahydroxydrim-7-en-6-one (ustusol F, 1 ), (2 R ,3 R ,5 R ,9 S ,10 R )-2,3,11-trihydroxydrim-7-en-6-one (9-deoxyustusol F, 2 ), (3 S ,5 R ,9 R ,10 R )-3,11,12-trihydroxydrim-7-en-6-one (ustusol G, 3 ), (5 S ,6 R ,9 S ,10 S , 11 R ,2' E ,4' E )-(11-dideoxy-11-hydroxystrobilactone A-6-yl)-5-carboxypenta-2,4-dienoate (ustusolate H, 4 ), ((5 S ,6 R ,9 S ,10 S )-strobilactone A-6-yl) (2 E ,4 E )-6,7-dihydroxyocta-2,4-dienoate (ustusolate I, 5 ), (2' E ,4' E ;6',7'- erythro )-ustusolate I ( 5a ) and (2' E ,4' E ; ent -6',7'- erythro )-ustusolate I ( 5b ), (2' E ,4' E ,6' R ,7' R )-ustusolate I ( 5c ) and (2' E ,4' E ,6' S ,7' S )-ustusolate I ( 5d ), (5 S ,6 R ,9 S ,10 S ,2' E ,4' E )-(strobilactone A-6-yl)-5-carboxypenta-2,4-dienoate (ustusolate J, 6 ), and (2 S ,5 S ,9 R ,10 S )-2,9,11-trihydroxydrim-7-en-6-one (ustusol B, 7 ), respectively. Compound 5 showed antiproliferation against the human tumor cells CAL-62 and MG-63 with the IC 50 values of 16.3 and 10.1 µM, respectively.

A new austin-type meroterpene, namely, ustusaustin A ( 1 ), together with seven related known analogues ( 2 - 8 ), were isolated and identified from the culture extract of Aspergillus ustus TK-5, an endophytic fungus obtained from the marine ascidian Pyura momus . The structures of these compounds were established on the basis of detailed interpretation of their NMR and MS data, and the relative and absolute configurations of 1 was confirmed by X-ray crystallographic analysis. Among them, ustusaustin A ( 1 ) represents the first example of 1'-nor-austin analogues with an unique 7-benzoylation. Compounds 1 - 4 , 6 , and 7 exhibited potent neuraminidase inhibitory activity and this is the first report of neuraminidase inhibitory activity for austin-type meroterpenes.

One new dihydrobenzofuran derivative ( 1 ), known depsipeptide emericellamide A ( 2 ), three known drimanes ( 3-5 ) and two artifact drimane derivatives ( 6 , 7 ) were isolated from the marine-derived fungus Aspergillus ustus KMM 4664. Their structures were determined by detailed analysis of spectroscopic data and by comparison with related known compounds. The absolute configuration of 1 was determined by time-dependent density functional theory (TD-DFT) calculations of ECD spectra. Compound 7 showed significant ability of the inhibition of spermatozoa to fertilize egg-cells of the sea urchin Strongylocentrotus intermedius with IC 50 value 21 µM.

Accumulation of two benzoyl esters in Aspergillus ustus after feeding with alcohols was reported 30 years ago. To the best of our knowledge, the biosynthesis for these esters has not been elucidated prior to this study. Here, we demonstrate that these compounds are artifical products of the phenethyl polyketide ustethylin A biosynthestic pathway. In addition, four aditional benzoyl esters with different methylation levels were also isolated and identified as shunt products. Feeding experiments provided evidence that the enzyme-bound polyketide acyl intermediates are hijacked by externally fed MeOH or EtOH, leading to the formation of the benzoyl esters.

Background: Aspergillus spp. of section Usti (A. ustus) represent a rare cause of invasive aspergillosis (IA). This multicenter study describes the epidemiology and outcome of A. ustus infections., Methods: Patients with A. ustus isolated from any clinical specimen were retrospectively identified in 22 hospitals from 8 countries. When available, isolates were sent for species identification (BenA/CaM sequencing) and antifungal susceptibility testing. Additional cases were identified by review of the literature. Cases were classified as proven/probable IA or no infection, according to standard international criteria., Results: Clinical report forms were obtained for 90 patients, of whom 27 had proven/probable IA. An additional 45 cases were identified from literature review for a total of 72 cases of proven/probable IA. Hematopoietic cell and solid-organ transplant recipients accounted for 47% and 33% cases, respectively. Only 8% patients were neutropenic at time of diagnosis. Ongoing antimold prophylaxis was present in 47% of cases. Pulmonary IA represented 67% of cases. Primary or secondary extrapulmonary sites of infection were observed in 46% of cases, with skin being affected in 28% of cases. Multiple antifungal drugs were used (consecutively or in combination) in 67% of cases. The 24-week mortality rate was 58%. A. calidoustus was the most frequent causal agent. Minimal inhibitory concentrations encompassing 90% isolates (MIC90) were 1, 8, >16, and 4 µg/mL for amphotericin B, voriconazole, posaconazole, and isavuconazole, respectively., Conclusions: Aspergillus ustus IA mainly occurred in nonneutropenic transplant patients and was frequently associated with extrapulmonary sites of infection. Mortality rate was high and optimal antifungal therapy remains to be defined., (© The Author(s) 2020. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Aspergillus sections Usti and Cavernicolarum are accommodated in the subgenus Nidulantes . In the present study, a polyphasic approach using morphology and multi-gene phylogeny was applied to investigate the taxonomy of these two sections. Based on the phylogenetic analysis, Aspergillus section Usti includes 25 species, which can be assigned to four series: Calidousti , Deflecti , Monodiorum and Usti. Aspergillus sigarelli is newly described in this section and this species was isolated from a cigarette from PR China and belongs to series Calidousti . It is clearly distinct from other members in this series based on ITS, BenA , CaM and RPB2 sequences. Aspergillus section Usti members like A. calidoustus and A. granulosus are important opportunistic pathogens, it is speculative that more pathogenetic species will be found by using polyphasic taxonomy approaches. Aspergillus section Cavernicolarum includes five species, the growth rates on agar media and size and ornamentation of conidia are important characters for differentiating species in section Cavernicolarum .

The Aspergilli of section Usti (group ustus ) are represented by over 20 species, of which Aspergillus calidoustus is the most relevant human pathogen. Invasive aspergillosis (IA) caused by these fungi is rare but could represent an emerging issue among the expanding population of patients with long-term immunosuppression receiving antifungal prophylaxis. Clinicians should be aware of this unusual type of IA, which often exhibits distinct clinical features, such as an insidious and prolonged course and a high occurrence of extra-pulmonary manifestations, such as skin/soft tissue or brain lesions. Moreover, these Aspergillus spp. pose a therapeutic challenge because of their decreased susceptibility to azole drugs. In this review, we outline the microbiological and clinical characteristics of IA due to Aspergillus spp. of section Usti and discuss the therapeutic options.

Invasive aspergillosis (IA) is the most common invasive fungal infection following a hematopoietic cell transplant, with emerging cryptic species exhibiting resistance to commonly used antifungals such as azoles. These species have been increasingly found after the introduction of anti-mold prophylaxis. We report a case of a 56-year-old female with primary myelofibrosis whose allogeneic hematopoietic cell transplant was complicated by disseminated fungal infection (skin, lung) due to Aspergillus calidoustus, a cryptic specie. Treatment of Aspergillus species remains challenging as these cryptic species are usually resistant to azoles including voriconazole which is the first line of treatment of IA. Infection was successfully treated with surgical excision and combination antifungal therapy based on in vitro susceptibility and synergy testing. Therapy included isavuconazole, a drug that has been shown to be non-inferior to voriconazole in the treatment of invasive mold infections.

Two new austalide meroterpenoids, named austalides V and W (1 and 2), were isolated from the fungus Aspergillus ustus VKM F-4692. Their structures were elucidated by extensive spectroscopic analysis and by comparison with related known compounds. The main structural feature of both compounds is a tetrahydrofuranyl ring (G), a structural fragment, first found in austalides. Austalides V (1) and W (2) were able to inhibit the propagation of prostate and bladder cancer cells; this biologic activity is possibly related to the inhibition of a number of key pathways regulating cell growth and migration., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Invasive fungal infections due to Aspergillus calidoustus with decreased azole susceptibility are emerging in the setting of azole prophylaxis and are associated with poor outcomes. We assessed the in vitro activity of antifungal drugs used alone or in combinations against A. calidoustus and found a synergistic effect between voriconazole and terbinafine at concentrations within the therapeutic range. An invertebrate Galleria mellonella model of A. calidoustus infection tended to support the potential benefit of this combination., (Copyright © 2018 American Society for Microbiology.)

Aspergillus calidoustus, previously classified as Aspergillus ustus, is an emerging pathogen in immunocompromised persons. We describe four recent cases of A. calidoustus and review 37 additional cases of A. calidoustus (n = 8) or A. ustus (n = 29) published through June 2016. Twenty (49%) cases occurred in patients with hematologic malignancy and/or receipt of hematopoietic cell transplantation, and 13 (32%) occurred in solid organ transplant recipients. Antifungal susceptibility was reported in 49% of cases and in 42% treatment failed. Overall mortality was 66% and, where reported, attributable mortality was 30%. A. calidoustus infection is associated with a high mortality rate and frequently displays in vitro antifungal resistance., (© 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Breakthrough invasive mold infections (IMIs) that occur during posaconazole or voriconazole prophylaxis are rare complications for which epidemiological data are lacking. This retrospective analysis comparing 24 microbiologically documented breakthrough with 66 nonbreakthrough IMIs shows a shift towards non-Aspergillus molds with a significantly increased proportion of rare multidrug-resistant molds., (© The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Aspergillus ustus is among the most ubiquitous soil species and has been implicated in human infections. The complete mitochondrial genome of A. ustus has been determined by high-throughput sequencing technology in this work. Our study revealed that the mitochondrial genome of A. ustus is 33,007 bp long, with AT content of 74.84%, which consists of a usual set of mitochondrial proteins and RNA genes, including large and small ribosomal RNAs, 15 proteins and 20 tRNA genes and contains two introns. Notably, it also contains three hypothetical proteins without obvious homology to any known proteins. All structural genes are located on one strand and are apparently transcribed in one direction. The complete mitochondrial genomes of A. ustus would be useful for future investigation of the genetics, evolution and clinical identification of Aspergillus species.