Spectrometric Characterization of Clinical and Environmental Isolates of Aspergillus Series Versicolores.

Aspergillus series Versicolores are molds distributed among 17 species, commonly found in our environment, and responsible for infections. Since 2022, a new taxonomy has grouped them into 4 major lineages: A. versicolor, A. subversicolor, A. sydowii, and A. creber. Matrix-Assisted Laser Desorption/Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF MS) could be a faster and more cost-effective alternative to molecular techniques for identifying them by developing a local database. To evaluate this technique, 30 isolates from Aspergillus series Versicolores were used. A total of 59 main spectra profiles (MSPs) were created in the local database. This protocol enabled accurate identification of 100% of the extracted isolates, of which 97% (29/30) were correctly identified with a log score ≥ 2.00. Some MSPs recorded as Aspergillus versicolor in the supplier's database could lead to false identifications as they did not match with the correct lineages. Although the local database is still limited in the number and diversity of species of Aspergillus series Versicolores, it is sufficiently effective for correct lineage identification according to the latest taxonomic revision, and better than the MALDI-TOF MS supplier's database. This technology could improve the speed and accuracy of routine fungal identification for these species.

6-Polyaminosteroid Squalamine Analogues Display Antibacterial Activity against Resistant Pathogens.

A series of 6-polyaminosteroid analogues of squalamine were synthesized with moderate to good yields and evaluated for their in vitro antimicrobial properties against both susceptible and resistant Gram-positive (vancomycin-resistant Enterococcus faecium and methicillin-resistant Staphylococcus aureus) and Gram-negative (carbapenem-resistant Acinetobacter baumannii and Pseudomonas aeruginosa) bacterial strains. Minimum inhibitory concentrations against Gram-positive bacteria ranged from 4 to 16 µg/mL for the most effective compounds, 4k and 4n, and showed an additive or synergistic effect with vancomycin or oxacillin. On the other hand, the derivative 4f, which carries a spermine moiety like that of the natural trodusquemine molecule, was found to be the most active derivative against all the resistant Gram-negative bacteria tested, with an MIC value of 16 µg/mL. Our results suggest that 6-polyaminosteroid analogues of squalamine are interesting candidates for Gram-positive bacterial infection treatments, as well as potent adjuvants to fight Gram-negative bacterial resistance.

Aspergilli series Versicolores: importance of species identification in the clinical setting.

The moulds of the genus Aspergillus section Nidulantes series Versicolores are ubiquitous and particularly recurrent in indoor air. They are considered present in 70% of the bioaerosols to which we are exposed most of our time spent indoors. With the taxonomic revision proposed in 2012 and the discovery of four new species, the series Versicolores currently includes 18 species. These moulds, although considered as cryptic (except Aspergillus sydowii), are opportunistic pathogens that can exhibit increased minimal inhibitory concentrations to conventional antifungal agents. In this review, we discuss the ecology and clinical implications of each species belonging to the series Versicolores. This survey also highlights the lack of consideration for taxonomic revisions in clinical practice and in scientific studies which greatly limits the acquisition of specific knowledge on species belonging to the series Versicolores.

Draft Genome Sequences of Three Airborne Aspergilli Series Versicolores.

The Aspergilli of the section Nidulantes series Versicolores are among the most recurrent molds in indoor environments. These species cause damage to the quality of air. Indeed, they are responsible for allergies, aggravation of asthma and can even cause infections in immunocompromised patients. Molds belonging to the Versicolores series also produce sterigmatocystin, a mycotoxin classified as potential human carcinogen by the International Agency for Research on Cancer (group 2B). Here, we provide for the first time the genome of three species of the series Versicolores: Aspergillus creber, Aspergillus jensenii and Aspergillus protuberus which are the most abundant species of this series in bioaerosols. The genomes of these three species could be assembled with a percentage of completeness of 97.02%, 96.21% and 95.35% for Aspergillus creber, A. jensenii and A. protuberus respectively. These data will allow to study the genes and gene clusters responsible for the expression of virulence factors, the biosynthesis of mycotoxins and the proliferation of these ubiquitous and recurrent molds.

Cellular Cytotoxicity and Oxidative Potential of Recurrent Molds of the Genus Aspergillus Series Versicolores.

Molds are ubiquitous biological pollutants in bioaerosols. Among these molds, the genus Aspergillus is found in the majority of indoor air samples, and includes several species with pathogenic and toxigenic properties. Aspergillus species in the series Versicolores remain little known despite recurrence in bioaerosols. In order to investigate their toxicity, we studied 22 isolates of clinical and environmental origin, corresponding to seven different species of the series Versicolores. Spore suspensions and ethyl acetate extracts prepared from fungal isolates were subjected to oxidative potential measurement using the dithiothreitol (DTT) test and cell survival measurement. The DTT tests showed that all species of the series Versicolores had an oxidative potential, either by their spores (especially for Aspergillus jensenii) or by the extracts (especially from Aspergillus amoenus). Measurements of cell survival of A549 and HaCaT cell lines showed that only the spore suspension containing 105 spores/mL of Aspergillus jensenii caused a significant decrease in survival after 72 h of exposure. The same tests performed with mixtures of 105 spores/mL showed a potentiation of the cytotoxic effect, with a significant decrease in cell survival for mixtures containing spores of two species (on A549 cells, p = 0.05 and HaCaT cells, p = 0.001) or three different species (on HaCaT cells, p = 0.05). Cell survival assays after 72 h of exposure to the fungal extracts showed that Aspergillus puulaauensis extract was the most cytotoxic (IC50 < 25 µg/mL), while Aspergillus fructus caused no significant decrease in cell survival.

First Characterization and Description of Aspergillus Series Versicolores in French Bioaerosols.

Air quality can be altered by fungal contaminants suspended in the air, forming bioaerosols. Aspergilli section Nidulantes series Versicolores are recurrent in bioaerosols and are mainly responsible for allergies and asthma aggravation. Phylogenetic studies recently identified 12 new species within this series. This study is the first to identify species of Aspergillus series Versicolores in French bioaerosols and to characterize them macroscopically, microscopically and molecularly. Bioaerosols were collected in a cancer treatment center, in contaminated homes and in agricultural environments. A total of 93 isolates were cultured on selective media, observed by optical microscopy and identified by benA amplification before sequencing. The field data (temperature and relative humidity) were statistically tested to explore the ecology of these species. Eight species were identified from bioaerosols: Aspergillus creber and A. jensenii, which represent more than 80% of the isolates, and A. protuberus, A. puulaauensis, A. sydowii, A. tabacinus, A. amoenus and A. fructus. Aspergilli series Versicolores are distributed differently depending on the sampling site and climatic determinants. Aspergillus protuberus was found in bioaerosols collected under significantly lower relative humidity (p = 3.899 × 10-4). Characterization and repartition of these isolates belonging to the Versicolores series constitute an important step to better assess exposure to fungal bioaerosols.

Long-Term In vitro Cultivation of Plasmodium falciparum in a Novel Cell Culture Device.

The standard in vitro cultivation procedure for Plasmodium falciparum requires gas exchange and a microaerophilic atmosphere. A novel system using a commercially available cell culture device (Petaka G3™; Celartia Ltd., Powell, OH) was assessed for long-term cultivation of a P. falciparum reference laboratory clone in normal air. Parasite growth during 30 days was similar, or better, in Petaka G3 than that in the standard cultivation method with gas exchange in a CO2 incubator. The successful cultivation of P. falciparum in the Petaka G3 device suggests that low O2 content available in hemoglobin and dissolved gas in the blood is sufficient for long-term cultivation. This finding may open the way to novel methods to cultivate and adapt P. falciparum field isolates to in vitro conditions with more ease.

Chaga ( Inonotus obliquus), a Future Potential Medicinal Fungus in Oncology? A Chemical Study and a Comparison of the Cytotoxicity Against Human Lung Adenocarcinoma Cells (A549) and Human Bronchial Epithelial Cells (BEAS-2B).

BACKGROUND: Inonotus obliquus, also known as Chaga, is a parasitic fungus growing on birches and used in traditional medicine (especially by Khanty people) to treat various health problems. In this study, we aimed to quantify the 3 metabolites frequently cited in literature, that is, betulin, betulinic acid, and inotodiol in the Chaga recently discovered in forests located in Normandy (France), and to compare their concentrations with Ukrainian and Canadian Chaga. This study also explores the cytotoxicity of the French Chaga against cancer-derived cells and transformed cells. METHODS: A quantification method by HPLC-MS-MS (high-performance liquid chromatography-tandem mass spectrometry) of betulin, betulinic acid, and inotodiol was developed to study the French Chaga and compare the concentration of these metabolites with extracts provided from Chaga growing in Canada and Ukraine. This method was also used to identify and quantify those 3 compounds in other traditional preparations of Chaga (aqueous extract, infusion, and decoction). Among these preparations, the aqueous extract that contains betulin, betulinic acid, and inotodiol was chosen to evaluate and compare its cytotoxic activity toward human lung adenocarcinoma cells (A549 line) and human bronchial epithelial cells (BEAS-2B line). RESULTS: French Chaga contains betulin and betulinic acid at higher levels than in other Chaga, whereas the concentration of inotodiol is greater in the Canadian Chaga. Moreover, the results highlighted a cytotoxic activity of the Chaga's aqueous extract after 48 and 72 hours of exposure with a higher effect on cancer-derived cells A549 than on normal transformed cells BEAS-2B ( P = 0.025 after 48 hours of exposure and P = 0.004 after 72 hours of exposure).