Mucor thermorhizoides-A New Species from Post-mining Site in Sudety Mountains (Poland).

Mucor representatives are mostly rapidly growing cosmopolitan soil saprotrophs of early diverged Mucoromycotina subphylum. Although this is the most speciose genus within the group, some lineages are still understudied. In this study, new species of Mucor was isolated from the post-mining area in southwestern Poland, where soil chemical composition analysis revealed high concentration of hydrocarbons and heavy metals. Phylogenetic analysis based on multigene phylogeny showed that the new isolate clusters distinctly from other Mucor species as a sister group to Mucor microsporus. New species Mucor thermorhizoides Abramczyk (Mucorales, Mucoromycota) is characterized by the extensive rhizoid production in elevated temperatures and formation of two layers of sporangiophores. It also significantly differs from M. microsporus in the shape of spores and the size of sporangia. M. thermorhizoides was shown to be able to grow in oligotrophic conditions at low temperatures. Together with M. microsporus they represent understudied and highly variable lineage of the Mucor genus.

Successful treatment of mixed pulmonary Aspergillus and Mucor infection using intrabronchial amphotericin B infusion: a case report and literature review.

BACKGROUND: Reports of pulmonary aspergillosis and mucormycosis co-infections are rare; thus, limited guidance is available on early diagnosis and treatment. We present a case of mixed pulmonary Aspergillus and Mucor infection and review the literature regarding this co-infection. The diagnosis and treatment methods are summarized to improve clinicians' understanding of the disease and to facilitate early diagnosis and treatment. CASE PRESENTATION: A 60-year-old male farmer with poorly controlled diabetes mellitus was admitted to hospital with a fever of unknown origin that had been present for 15 days and pulmonary aspergillosis complicated by Mucor spp. INFECTION: Because multiple lobes were involved, the infection worsened despite surgical resection and antifungal therapy. Finally, we treated this patient with a bronchoscopic infusion of amphotericin B. After four courses of bronchoscopic amphotericin B infusion, we observed rapid clinical improvement and subsequent resolution of pulmonary infiltrates. CONCLUSION: Our case highlights the use of bronchoscopy in the successful clinical treatment of invasive fungal diseases of the lung.

Bio-detoxification of Jatropha curcas L. cake by a soil-borne Mucor circinelloides strain using a zebrafish survival model and solid-state fermentation.

AIMS: The aims of the study were to (i) improve the evaluation criteria of detoxifying Jatropha curcas L. cake (JCC), (ii) isolate and characterize a JCC tolerant strain, (iii) explore its JCC detoxifying potential. METHODS AND RESULTS: The zebrafish was employed as a survival model to screen the strains capable of detoxifying JCC. A strain identified as Mucor circinelloides SCYA25, which is highly capable of degrading all toxic components, was isolated from soil. Different solid-state fermentation parameters were optimized by response surface methodology. The optimal values for inoculation amount, moisture content, temperature, and time were found to be 18% (1·8 × 106 spores g-1 cake), 66%, 26, and 36 days, respectively, to achieve maximum detoxification of the JCC (92%). Under optimal fermentation conditions, the protein content of JCC was increased, while the concentrations of ether extract, crude fiber, toxins, and anti-nutritional substances were all degraded considerably (P < 0·05). Scanning electron microscopy and Fourier transform infrared spectrometer analysis revealed that the fermentation process could disrupt the surface structure and improve the ratio of α-helix to ß-folding in the JCC protein, which may improve the digestibility when the detoxified JCC is used as a feedstuff. CONCLUSIONS: Our results indicate that M. circinelloides SCYA25 is able to detoxify JCC and improve its nutritional profile, which is beneficial to the safe utilization of JCC as a protein feedstuff. SIGNIFICANCE AND IMPACT OF THE STUDY: The newly identified M. circinelloides SCYA25 detoxified JCC in a safe manner to provide a potential alternative to soybean meal for the feed industry. These results also provide a new perspective and method for the toxicity evaluation and utilization of JCC and similar toxic agricultural by-products.

Invasive Mucormycosis in Children With Malignancies: Report From the Infection Working Group of the Hellenic Society of Pediatric Hematology-Oncology.

Mucormycosis is an invasive, life-threatening fungal infection that mainly affects immunocompromised hosts. We collected data of pediatric mucormycosis cases from all 7 Greek Hematology-Oncology Departments for the years 2008-2017. Six cases of invasive mucormycosis diagnosed during treatment for malignancies were included in the study. In 4 children (66%) mucormycosis occurred within the first 20 days after diagnosis of the underlying disease. Two cases were classified as proven mucormycosis and 4 as probable. The most frequently recorded species was Rhizopus arrhizus (2 patients), followed by Mucor spp (1), and Lichtheimia spp (1). All patients received liposomal amphotericin B. Combined antifungal treatment was used in 5 cases. Surgical excision was performed in 4 cases (66%). Two patients died at 6 and 12 months after the diagnosis, respectively, 1 (17%) because of mucormycosis. Our data suggest that mucormycosis may occur early after the initiation of intensive chemotherapy in children with malignancies.

Incidence, predisposing conditions and outcomes of cutaneous mucormycosis: A national database study.

BACKGROUND: The body of evidence on cutaneous mucormycosis is largely derived from case reports or single-centre databases. OBJECTIVES: Our study aimed to describe incidence, predisposing factors and inpatient outcomes of cutaneous mucormycosis in the United States. METHODS: We conducted a population-based retrospective study using the National Inpatient Sample 2016-17 data. Fifty-six discharges had a diagnosis of cutaneous mucormycosis on the International Classification of Diseases, tenth revision. Descriptive analysis was performed for the demographics, predisposing factors, length of stay (LOS), cost and inpatient mortality. The NIS represents 20% of all discharges in the United States, which allowed us to estimate the national incidence of cutaneous mucormycosis. RESULTS: An estimated total of 280 admissions occurred between 2016 and 2017, indicating 3.9 cases per million admissions across the United States. The estimated incidence rate was 0.43 cases per million people per year. Median age was 49.5 (19-59) years, 44.6% were female, and 54.9% were Caucasian. We identified haematologic malignancies (48.2%) and solid organ transplantations (10.7%), often accompanied by skin/soft tissue or post-procedural infections, were the most common predisposing conditions. Median LOS was 15 (6-31) days, median total charges were 187,030 (65,962-446,265) USD, and in-hospital mortality rate was 16.1%. CONCLUSIONS: In current clinical practice, physicians may encounter cutaneous mucormycosis most commonly in severely immunocompromised hosts with haematologic malignancies or transplantations, accompanied by skin/soft tissue or post-procedural infections. A high index of suspicion and prompt tissue sampling in at-risk groups is important to improve the outcomes.

Frequency of occurrence, seasonal variation and antifungal susceptibility of opportunistic Mucorales isolated from hospital soils in Iran.

BACKGROUND: Mucorales are opportunistic pathogens that can cause life-threatening diseases predominantly in immunocompromised patients. OBJECTIVES: This study aimed to investigate the frequency, seasonal variation and antifungal susceptibility of pathogenic Mucorales in the soil collected from seven hospitals in Urmia, Iran, between November 2017 and July 2018 in four different seasons. METHODS: Mucorales isolates obtained from soil were characterised based on conventional and molecular assays. In addition, in vitro antifungal susceptibility was performed using the CLSI M38Ed3 procedure. RESULTS: Out of 196 tested soil samples, 80 (40.8%) samples were positive for mucoralean fungi. Rhizopus arrhizus var. arrhizus (n = 47) was the most frequent species followed by Mucor circinelloides (n = 21) and Cunninghamella echinulata (n = 6). A seasonal variation in the frequency of Mucorales in soil was detected with a maximum of culture-positive soil samples detected in wet autumn (43.2%) followed by winter (23.4%), summer (19.7%) and spring (13.6%). In vitro antifungal susceptibility testing for 80 environmental isolates exhibited MIC of ≤2 µg/ml for amphotericin B indicating the smallest range of MIC variation among the tested Mucorales (range: 0.125-2 µg/ml). Among the azoles, posaconazole was the most effective antifungals (GM MIC, 0.724 µg/ml). CONCLUSIONS: We considered associations of species and seasonal frequencies between soil mucoralean fungi and mucormycosis. The effect of opportunistic Mucorales dominating in the soil and prevalent causative agents of mucormycosis in Iran reported in the literatures but more comprehensive studies are needed to confirm this conclusion.

Biodegradation of fluorene by the newly isolated marine-derived fungus, Mucor irregularis strain bpo1 using response surface methodology.

Fluorene, a low molecular weight polycyclic aromatic hydrocarbon (PAH), is of immense environmental interest because of its carcinogenicity, teratogenicity, mutagenicity, toxicity and persistence to microbial degradation. Existentially, there is paucity of information on PAH degradation by fungi isolated from marine environment. Therefore, this study investigated fluorene degradation efficiency of marine derived filamentous fungus, Mucor irregularis strain bpo1 (GenBank Accession Number: MK373020). Response Surface Methodology (RSM) using Box-Behnken Design (BBD) was successfully deployed in the optimization of process parameters (pH-7, temperature-32.5 °C, substrate concentration-100 mg L-1 and dry weight-2 g) resulting in 81.50% fluorene degradation on 5th day. The design and regression model were found to be statistically significant, adequate and appropriate with p < 0.0001, F value= 202.39, and predicted coefficient of determination (R2 =0.9991). Optimization of the vital constituents of the mineral salt medium (MSM) used for the study using RSM-Central Composite Design (CCD) resulted in 79.80% fluorene degradation rate. Enhanced fluorene degradation efficiency (82.50%) was recorded when the optimized process variables were subjected to growth-linked validation experiments. The enzyme activities revealed 87%, 59% and 31% induction of laccase, manganese peroxidase and lignin peroxidase respectively. Four metabolites; 9H-fluoren-9-one, benzene-1,2-dicarboxylic acid, 2-hydroxybenzoic acid and phenol obtained after the experiment were characterized and confirmed with GC-MS analysis. The findings revealed the promising potentials of M. irregularis in PAH degradation and by extension green remediation technology.

Outbreaks of Mucorales and the Species Involved.

The order Mucorales is an ancient group of fungi classified in the subphylum Mucoromycotina. Mucorales are mainly fast-growing saprotrophs that belong to the first colonizers of diverse organic materials and represent a permanent part of the human environment. Several species are able to cause human infections (mucormycoses) predominantly in patients with impaired immune system, diabetes, or deep trauma. In this review, we compiled 32 reports on community- and hospital-acquired outbreaks caused by Mucorales. The most common source of mucoralean outbreaks was contaminated medical devices that are responsible for 40.7% of the outbreaks followed by contaminated air (31.3%), traumatic inoculation of soil or foreign bodies (9.4%), and the contact (6.2%) or the ingestion (6.2%) of contaminated plant material. The most prevalent species were Rhizopus arrhizus and R. microsporus causing 57% of the outbreaks. The genus Rhizomucor was dominating in outbreaks related to contaminated air while outbreaks of Lichtheimia species and Mucor circinelloides were transmitted by direct contact. Outbreaks with the involvement of several species are reported. Subtyping of strains revealed clonality in two outbreaks and no close relation in two other outbreaks. Based on the existing data, outbreaks of Mucorales can be caused by heterogeneous sources consisting of different strains or different species. Person-to-person transmission cannot be excluded because Mucorales can sporulate on wounds. For a better understanding and prevention of outbreaks, we need to increase our knowledge on the physiology, ecology, and population structure of outbreak causing species and more subtyping data.

Mucor chuxiongensis sp. nov., a novel fungal species isolated from rotten wood.

Three strains of a novel mucoralean fungus were isolated from samples of decayed wood, which were collected from three locations near the city of Chuxiong, Yunnan province, China. These isolates were identified as a novel species through comparison of sequences in the ITS sequence, the D1/D2 domains of the LSU rRNA gene, and other taxonomic characteristics. The results demonstrated that these isolates represent a novel mucoralean fungus species belonging to the genus Mucor. The ITS sequence of Mucor chuxiongensissp. nov. differed from its closest relative, Mucor guilliermondii CBS 174.27T, by 13.1 % sequence divergence (39 substitutions and 38 gaps), and the D1/D2 sequences of the novel strains differed by 13 nt substitutions and one gap (1.9 %) from the ex-type strain. On potato dextrose agar, malt extract agar and synthetic mucor agar, the isolates grew slowly below 10 °C, rapidly at 25-30 °C, and could not grow well at 35 °C. The holotype strain of Mucor chuxiongensis sp. nov. is NYNU 174111 (CICC 41666T=CBS 143707T).

Disfiguring Mucor irregularis Infection Cured by Amphotericin B and Itraconazole: A Case Report and Treatment Experience.

We report a case of primary cutaneous mucormycosis caused by Mucor irregularis. A 52-year-old male farmer was presented to our hospital with a history of progressive nodule and plaque with ulceration on the face for two and a half years. Broad, aseptate hyphae were seen in direct KOH examination and biopsy. Fungal culture showed light yellow filamentous colonies. The rRNA sequencing revealed M. irregularis was the responsible fungus. Amphotericin B in gradually increasing dose and itraconazole were administered. When the cumulative dose of amphotericin B was 1500 mg, the skin lesion improved significantly with remaining scars on the face. Then, the patient received sequential oral itraconazole treatment for 8 months. There was no recurrence up to now through follow-ups.

Mucor sp.-An endophyte of Brassicaceae capable of surviving in toxic metal-rich sites.

The aim of this study was to assess the biodiversity of endophytic fungi from Arabidopsis arenosa growing on a post mining waste dump and to evaluate their role in plant adaptation to metal toxicity. Severeal of the fungi were beneficial for the plant. Among them, a fungus belonging to the Mucor genus, was found to interact with a broad range of plants, including Brassicaceae metallophytes. Mucor sp. was shown to be highly tolerant to elevated levels of Zn, Cd, and Pb and to accelerate plant-host growth under either toxic-metal stress or control conditions. When inoculated with Mucor sp., A. arenosa under toxic-metal stress acquired more N and showed significantly down-regulated catalase activity, which suggests suppression of toxic-metal-induced oxidative stress. We used the model plant-A. thaliana to evaluate the dynamics of plant-tissue colonization by the fungus as monitored with qPCR and to analyze the host's transcriptome response during early stages of the interaction. The results revealed the induction of a plant-defense and stress-related response on the 5th day of co-culture, which was in accord with the decrease of fungal abundance in shoots on the 6th day of interaction. Presented results demonstrate the importance of endophytic fungi in plant toxic-metal tolerance.

[The 471st case: duodenal ulcer, mucor infection, and elevated IgG(4)].

Mucor infection is rarely reported in non-immunocompromised population, especially in isolated gastrointestinal tracts. IgG(4)-related diseases (IgG(4)-RD) have been recognized in recent years, but secondary causes of IgG(4) elevation should be differentiated. We reported a young man with duodenal mass and ulcer and high serum IgG(4) level. Histological biopsy of the mass revealed positive mucor mycelium and infiltration of IgG(4) positive plasma cells. Serum IgG(4) decreased to normal range after surgical resection and systemic antifungal treatment. This case suggests that isolated mucor mycosis infection can develop in the digestive tract and mimics as IgG(4)-related disease.

Identification and Isolation of Glucosytransferases (GT) Expressed Fungi Using a Two-Photon Ratiometric Fluorescent Probe Activated by GT.

As is well-known, fungi are an important biocatalysis model of glucosylation and have been widely applied for bioactive compounds glucosylation mediated by the intracellular glucosytransferases (GTs). However, there is no efficient method for the real-time detection of GTs and the rapid isolation of the target fungi strains with the high expression of GTs. In the present work, we first developed a two-photon ratiometric fluorescent probe N-( n-butyl)-4-hydroxy-1,8-naphthalimide (NHN) for detecting the glucosyltransferases activity and intracellular imaging of GTs. Under UV light (365 nm), the transformed product of NHN mediated by intracellular glucosyltransferase displayed blue emission to guide the rapid isolation of fungal strains possessing overexpression of GTs from complex soil samples. Finally, by using the fluorescent probe, two target fungi were isolated and identified to be Rhizopus oryzae and Mucor circinelloides by molecular analysis, and they exhibited a robust capability for regio- and stereospecific O-glycosylation. Our results fully demonstrated that NHN may be a promising tool for guiding real-time GTs activity in fungal strains and even for developing natural fungal strains with GTs overexpression.

Efficacy of Pseudomonas fluorescens for control of Mucor rot of apple during commercial storage and potential modes of action.

The ability of Pseudomonas fluorescens isolates 1-112, 2-28, and 4-6, to control Mucor piriformis (Mucor rot) on Gala, McIntosh, Ambrosia, and Spartan apple cultivars in commercial cold storage and their possible mechanisms of action were investigated. Isolates 1-112 and 2-28 provided significant levels of disease control on McIntosh and Spartan apples, while isolate 4-6 provided control of Mucor rot on Gala and Spartan apples, compared with control fruits after 15 weeks of storage at 0 °C. Mycelial growth of M. piriformis was markedly inhibited by cell-free supernatant and volatile organic compounds produced by P. fluorescens isolates, in vitro. In filter-sterilized apple juice, living cells of all 3 P. fluorescens isolates or their metabolites significantly inhibited spore germination by 99.8% and 61.6%, on average, respectively. Electron microscopy indicated that all 3 isolates of P. fluorescens colonized the hyphae of M. piriformis, but only isolate 1-112 was observed to colonize M. piriformis spores in vitro. In the wounds of apple, all 3 isolates formed a biofilm on the fungal hyphae and on the fruit tissue. Potential mechanisms of antagonism utilized by P. fluorescens against M. piriformis may include competition for nutrients and space, production of inhibitory metabolites and volatiles, and biofilm formation, leading to inhibition of spore germination and mycelial growth.

Biochemical mechanism of phytoremediation process of lead and cadmium pollution with Mucor circinelloides and Trichoderma asperellum.

This study focused on the bioremediation mechanisms of lead (0, 100, 500, 1000 mg kg-1) and cadmium (0,10,50,100 mg kg-1) contaminated soil using two indigenous fungi selected from mine tailings as the phytostimulation of Arabidopsis thaliana. The two fungal strains were characterized as Mucor circinelloides (MC) and Trichoderma asperellum (TA) by internal transcribed spacer sequencing at the genetic levels. Our research revealed that Cadmium was more toxic to plant growth than lead and meanwhile, MC and TA can strengthen A. thaliana tolerance to cadmium and lead with 40.19-117.50% higher root length and 58.31-154.14% shoot fresh weight of plant compared to non-inoculation. In this study, TA exhibited a higher potential to the inactivation of cadmium; however, MC was more effective in lead passivation. There was a direct correlation between the type of fungi, heavy metal content, heavy metal type and oxidative damage in plant. Both lead and cadmium induced oxidative damage as indicated by increased superoxide dismutase and catalase activities, while the antioxidant levels were significantly higher in fungal inoculated plants compared with those non-inoculated. The analysis of soil enzyme activity and taxonomic richness uncovered that the dominant structures of soil microbial community were altered by exogenous microbial agents. MC enhanced higher microbial diversity and soil enzyme activity than TA. The two indigenous fungi lessened several limiting factors with respect to phytoremediation technology, such as soil chemistry, contamination level and transformation, and metal solubility.

Successful Treatment by Surgery of a Primary Cutaneous Mucormycosis Caused by Mucor irregularis.

We report a case of primary cutaneous mucormycosis caused by Mucor irregularis. A 66-year-old man was presented to our hospital with a history of gradually enlarging plaque on the right leg for about a year. The identification of pathogen based on the fungus morphology and DNA sequencing revealed M. irregularis as the responsible fungus for skin lesion. The lesion was removed incidentally by a surgery procedure, and no recrudescence was seen during a follow-up of 24-month observation.

Invasive mould infections in the ICU setting: complexities and solutions.

Infections caused by filamentous fungi represent a major burden in the ICU. Invasive aspergillosis is emerging in non-neutropenic individuals with predisposing conditions, e.g. corticosteroid treatment, chronic obstructive pulmonary disease, liver cirrhosis, solid organ cancer, HIV infection and transplantation. Diagnosis is challenging because the signs and symptoms are non-specific, and initiation of additional diagnostic examinations is often delayed because clinical suspicion is low. Isolation of an Aspergillus species from the respiratory tract in critically ill patients, and tests such as serum galactomannan, bronchoalveolar lavage 1-3-ß-d-glucan and specific PCR should be interpreted with caution. ICU patients should start adequate antifungal therapy upon suspicion of invasive aspergillosis, without awaiting definitive proof. Voriconazole, and now isavuconazole, are the drugs of choice. Mucormycosis is a rare, but increasingly prevalent disease that occurs mainly in patients with uncontrolled diabetes mellitus, immunocompromised individuals or previously healthy patients with open wounds contaminated with Mucorales. A high proportion of cases are diagnosed in the ICU. Rapidly progressing necrotizing lesions in the rhino-sinusal area, the lungs or skin and soft tissues are the characteristic presentation. Confirmation of diagnosis is based on demonstration of tissue invasion by non-septate hyphae, and by new promising molecular techniques. Control of underlying predisposing conditions, rapid surgical resection and administration of liposomal amphotericin B are the main therapeutic actions, but new agents such as isavuconazole are a promising alternative. Patients with mucormycosis receive a substantial part of their care in ICUs and, despite advances in diagnosis and treatment, mortality remains very high.

Generation of lycopene-overproducing strains of the fungus Mucor circinelloides reveals important aspects of lycopene formation and accumulation.

OBJECTIVES: To generate lycopene-overproducing strains of the fungus Mucor circinelloides with interest for industrial production and to gain insight into the catalytic mechanism of lycopene cyclase and regulatory process during lycopene overaccumulation. RESULTS: Three lycopene-overproducing mutants were generated by classic mutagenesis techniques from a ß-carotene-overproducing strain. They carried distinct mutations in the carRP gene encoding lycopene cyclase that produced loss of enzymatic activity to different extents. In one mutant (MU616), the lycopene cyclase was completely destroyed, and a 43.8% (1.1 mg/g dry mass) increase in lycopene production was observed in comparison to that by the previously existing lycopene overproducer. In addition, feedback regulation of the end product was suggested in lycopene-overproducing strains. CONCLUSIONS: A lycopene-overaccumulating strain of the fungus M. circinelloides was generated that could be an alternative for the industrial production of lycopene. Vital catalytic residues for lycopene cyclase activity and the potential mechanism of lycopene formation and accumulation were identified.

Alleviation of heavy metal toxicity and phytostimulation of Brassica campestris L. by endophytic Mucor sp. MHR-7.

Heavy metal (HM) pollution is of great concern in countries like Pakistan where a huge proportion of human population is exposed to it. These toxic metals are making their way from water bodies to soil where it not only interferes with plant growth and development but also initiates serious health issues in human consuming the produce of such soils. Bioremediation is one of the most viable and efficient solution for the problem. Purpose of the current study was to isolate endophytic fungi from plants grown on HM contaminated soil and screen them for their ability to tolerate multiple HM including chromium (Cr6+), manganese (Mn2+), cobalt (Co2+), copper (Cu2+) and zinc (Zn2+). Out of 27 isolated endophytes, only one strain (MHR-7) was selected for multiple heavy metals tolerance. The strain was identified as Mucor sp. by 18S and 28S ribosomal RNA internal transcribed spacer (ITS) 1 and 4 sequence homology. The strain effectively tolerated up to 900µgmL-1 of these heavy metals showing no remarkable effect on its growth. The adverse effect of the heavy metals, measured as reduction of the fungal growth increased with increasing concentration of the metals. The strain was able to remove 60-87% of heavy metals from broth culture when supplied with 300µgmL-1 of these metals. A trend of decline in bioremediation potential of the strain was observed with increasing amount of metals. The strain removed metals by biotransformation and/or accumulation of heavy metal in its hyphae. Application of Mucor sp. MHR-7 locked down HM in tis mycelium thereby making them less available to plant root reducing HM uptake and toxicity in mustard. Besides its bioremediation potential, the strain was also able to produce IAA, ACC deaminase and solubilize phosphate making it excellent phytostimulant fungus. It is concluded that MHR-7 is an excellent candidate for use as biofertilizer in fields affected with heavy metals.