Echinocandin B (ECB) is a key precursor of the antifungal drug anidulafungin. It is a secondary metabolite of Aspergillus nidulans, and its titer in fermentation is significantly affected by the ECB synthesis pathway and cell morphology. In this study, the key genes related to the transcription activation, hydroxylation, and cell morphology during ECB biosynthesis were investigated to increase the fermentation titer of ECB and to change the cell morphology of Aspergillus nidulans to reduce the viscosity of the fermentation broth. The results indicated that after overexpression of ecdB and ecdK, the ECB titer increased by 25.8% and 23.7%, respectively, compared with that of the wild-type strain, reaching (2 030.5±99.2) mg/L and (1 996.4±151.4) mg/L. However, the deletion of fksA associated with cell wall synthesis resulted in damage to the cell wall, affecting strain growth and product synthesis. The engineered strain overexpressing ecdB was fermented in a 50-L bioreactor, in which the ECB titer reached 2 234.5 mg/L. The findings laid a research foundation for the subsequent metabolic engineering of this strain.
Fermentation ; Aspergillus nidulans/genetics* ; Echinocandins/genetics* ; Bioreactors/microbiology* ; Fungal Proteins/biosynthesis* ; Metabolic Engineering

Objective: To explore the epidemiological characteristics of sample distribution and antifungal susceptibilities of clinically invasive C. tropicalis isolates from 2017 to 2021 in East China. Methods: Using a retrospective analysis, the East China Invasive Fungal Infection Group (ECIFIG) collected C. tropicalis clinically isolated from 32 hospitals in East China between January 2017 and December 2021. The identification results of the strains were reviewed using mass spectrometry by the central laboratory of the Shanghai East Hospital. The minimum inhibitory concentrations (MICs) of the strains against fluconazole (FLU), voriconazole (VOR), itraconazole (ITR), Posaconazole (POS), isavuconazole (ISA), anidulafungin (ANI), caspofungin (CAS), micafungin (MICA) and 5-fluorocytosine (FCT) were tested by the ThermoFisher CMC1JHY colorimetric microdilution method. The MIC of amphotericin B (AMB) was tested by the broth microdilution method. The MIC results were analyzed based on the clinical breakpoints and epidemiological cutoff values (ECV) published by the Clinical and Laboratory Standards Institute (CLSI) M27 Ed3 and M57 Ed4 documents. Data analysis was conducted using the Kruskal-Wallis test and paired t-test. Results: In total, 305 C. tropicalis isolates were collected. There were 38.0% (116/305) strains isolated from blood, 11.5% (35/305) ascites, 8.9% (27/305) catheter and 8.9% (27/305) drainage fluid. The resistance rate of C. tropicalis to FLU was 32.5%, to VOR was 28.5%, and the cross-resistance rate to FLU and VOR was 28.5%. The wild-type proportions for ITR and POS were 79.3% and 29.2% respectively. There was no significant difference in resistance rates, MIC₅₀, and MIC₉₀ of FLU and VOR, or in the wild-type rates of ITR and POS over five years. More than 95.0% of the isolates were susceptible to echinocandins. However, one strain was identified as being multi-drug resistant. In azole antifungals, voriconazole, itraconazole, posaconazole, and isavuconazole have similar GM MIC values. The GM MIC of fluconazole is significantly higher than that of itraconazole (t=9.95, P<0.05), posaconazole (t=9.99, P<0.05), and voriconazole (t=10.01, P<0.05), Meanwhile, among echinocandins, the GM MIC of ANI was comparable to that of CAS (t=1.17, P>0.05), both of which were significantly higher than MICA (t=11.56, P<0.05; t=4.15, P<0.05). Conclusion: The clinical isolates of C. tropicalis in East China from 2017 to 2021 were relatively susceptible to echinocandins. However, there was consistently high resistance to fluconazole and voriconazole. More intensive efforts should be made on the monitoring of drug resistance in C. tropicalis.
Humans ; Antifungal Agents/pharmacology* ; Fluconazole/pharmacology* ; Candida tropicalis ; Voriconazole/pharmacology* ; Itraconazole/pharmacology* ; Retrospective Studies ; Candida ; China/epidemiology* ; Echinocandins/pharmacology* ; Microbial Sensitivity Tests

Objective: To explore the epidemiological characteristics of sample distribution and antifungal susceptibilities of clinically invasive C. tropicalis isolates from 2017 to 2021 in East China. Methods: Using a retrospective analysis, the East China Invasive Fungal Infection Group (ECIFIG) collected C. tropicalis clinically isolated from 32 hospitals in East China between January 2017 and December 2021. The identification results of the strains were reviewed using mass spectrometry by the central laboratory of the Shanghai East Hospital. The minimum inhibitory concentrations (MICs) of the strains against fluconazole (FLU), voriconazole (VOR), itraconazole (ITR), Posaconazole (POS), isavuconazole (ISA), anidulafungin (ANI), caspofungin (CAS), micafungin (MICA) and 5-fluorocytosine (FCT) were tested by the ThermoFisher CMC1JHY colorimetric microdilution method. The MIC of amphotericin B (AMB) was tested by the broth microdilution method. The MIC results were analyzed based on the clinical breakpoints and epidemiological cutoff values (ECV) published by the Clinical and Laboratory Standards Institute (CLSI) M27 Ed3 and M57 Ed4 documents. Data analysis was conducted using the Kruskal-Wallis test and paired t-test. Results: In total, 305 C. tropicalis isolates were collected. There were 38.0% (116/305) strains isolated from blood, 11.5% (35/305) ascites, 8.9% (27/305) catheter and 8.9% (27/305) drainage fluid. The resistance rate of C. tropicalis to FLU was 32.5%, to VOR was 28.5%, and the cross-resistance rate to FLU and VOR was 28.5%. The wild-type proportions for ITR and POS were 79.3% and 29.2% respectively. There was no significant difference in resistance rates, MIC₅₀, and MIC₉₀ of FLU and VOR, or in the wild-type rates of ITR and POS over five years. More than 95.0% of the isolates were susceptible to echinocandins. However, one strain was identified as being multi-drug resistant. In azole antifungals, voriconazole, itraconazole, posaconazole, and isavuconazole have similar GM MIC values. The GM MIC of fluconazole is significantly higher than that of itraconazole (t=9.95, P<0.05), posaconazole (t=9.99, P<0.05), and voriconazole (t=10.01, P<0.05), Meanwhile, among echinocandins, the GM MIC of ANI was comparable to that of CAS (t=1.17, P>0.05), both of which were significantly higher than MICA (t=11.56, P<0.05; t=4.15, P<0.05). Conclusion: The clinical isolates of C. tropicalis in East China from 2017 to 2021 were relatively susceptible to echinocandins. However, there was consistently high resistance to fluconazole and voriconazole. More intensive efforts should be made on the monitoring of drug resistance in C. tropicalis.
Humans ; Antifungal Agents/pharmacology* ; Fluconazole/pharmacology* ; Candida tropicalis ; Voriconazole/pharmacology* ; Itraconazole/pharmacology* ; Retrospective Studies ; Candida ; China/epidemiology* ; Echinocandins/pharmacology* ; Microbial Sensitivity Tests

BACKGROUND: Candida auris was first isolated from the ears of Japanese and Korean patients. However, the prevalence of yeast isolates from ear cultures and their antifungal susceptibility profiles in these nations remain unclear.METHODS: We assessed yeast isolates recovered from ear cultures from a university hospital in Korea over a 4-year period from January 2014 to December 2017. Species identification was performed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and/or sequence analysis. Antifungal minimal inhibitory concentrations (MICs) were determined using the broth microdilution method of the Clinical and Laboratory Standards Institute.RESULTS: Among 81 non-duplicate isolates from ear cultures, Cadida parapsilosis was the most frequently detected yeast species (34.6%), followed by C. auris (28.4%), Candida metapsilosis (9.9%), Candida orthopsilosis (8.6%), Candida albicans (7.4%), and others (11.1%). The MICs of the isolates were 0.125 to > 64 µg/mL, ≤0.03 to 4 µg/mL, 0.25 to 1 µg/mL, 0.125 to 1 µg/mL, and ≤0.03 to 2 µg/mL for fluconazole, voriconazole, amphotericin B, caspofungin, and micafungin, respectively. Of the 81 isolates, 44.4% (36/81) showed decreased susceptibility to fluconazole (MIC ≥4 µg/mL). Of the 23 C. auris isolates, 19 (82.6%) had a fluconazole MIC of ≥32 µg/mL. None of the isolates showed resistance to amphotericin B or echinocandins. Most of these patients suffered from chronic otitis media (84%).CONCLUSION: Candida parapsilosis complex and C. auris were the yeast species identified most frequently from ear cultures and they exhibited a high rate of fluconazole non-susceptibility, particularly C. auris.
Amphotericin B ; Asian Continental Ancestry Group ; Candida ; Candida albicans ; Ear ; Echinocandins ; Fluconazole ; Humans ; Korea ; Mass Spectrometry ; Methods ; Otitis Media ; Prevalence ; Sequence Analysis ; Voriconazole ; Yeasts

BACKGROUND: Invasive fungal infections (IFIs) are a life-threatening problem in immunocompromised patients. Despite timely diagnosis and appropriate antifungal therapy, clinical outcomes of IFIs remain unsatisfactory, necessitating treatment with a combination of antifungal agents. Therefore, childhood leukemic patients treated with voriconazole plus caspofungin were evaluated for the safety and efficacy of the combination antifungal therapy to treat IFIs. METHODS: In this retrospective study, medical records were retrieved for patients admitted to the Pediatric Department of Yeungnam University Hospital, Daegu, South Korea, between April 2009 and May 2013. Medical records of 22 patients were analyzed. RESULTS: Of the 22 patients studied, nine (41%) had been diagnosed with probable IFI, and 13 (59%) with possible IFI. All patients, except one, were already receiving antifungal monotherapy for the treatment of neutropenic fever. After a diagnosis of IFI was confirmed, antifungal monotherapy was replaced with combination therapy. The study's overall response rate was 90.9%, with complete responses in 86.3% of the patients. Two patients experienced a side effect of a small increase in liver enzyme levels. CONCLUSION: Voriconazole plus caspofungin combination therapy is an effective and safe treatment for serious IFI in pediatric patients with acute leukemia.
Antifungal Agents ; Aspergillosis ; Child* ; Daegu ; Diagnosis ; Echinocandins ; Fever ; Humans ; Immunocompromised Host ; Korea ; Leukemia* ; Liver ; Medical Records ; Retrospective Studies ; Voriconazole*

Anidulafungin is an effective antifungal medicine, which can inhibit activities of candida in vitro and in vivo. Echinocandin B (ECB) is the key precursor of Anidulafungin, thus the price and market prospect of Anidulafungin is directly due to the fermentation titer of ECB. In this study, Aspergillus nidulans was used for ECB fermentation, and the influence of adding microparticles on ECB fermentation was studied, such as talcum powder, Al2O3, and glass beads. The particle size and concentration were the key factors for mycelium morphology and ECB production, and ECB production could reach 1 262.9 mg/L and 1 344.1 mg/L by adding talcum powder of 20 g/L (d50 = 14.2 μm) and 7 glass beads (6 mm), an increase by 33.2% and 41.7%, respectively. The results indicated that the mycelium morphology of filamentous microorganisms and the product yield of fermentation could be improved by adding microparticles remarkably, and it provide an important method for the fermentative optimization of filamentous microorganisms.
Antifungal Agents ; metabolism ; Aspergillus nidulans ; metabolism ; Echinocandins ; biosynthesis ; Fermentation ; Fungal Proteins ; biosynthesis ; Industrial Microbiology ; methods

OBJECTIVETo evaluate antifungal combination strategy in children with hematologic diseases and invasive fungal disease( IFD).

METHODSA retrospective clinical study was performed based on 67 childhood patients with hematologic diseases and IFD who firstly accepted combination antifungal therapy for ≥ 7 days during January 2012 and December 2014. Of them, 11 cases received combination of echinocandin with azole, 10 cases received combination of echinocandin with amphotericin B, and 46 cases received combination of azole with amphotericin B.

RESULTSOverall response rate was 79.1%. Univariate analysis revealed that granulocyte recovery (P=0.031), status of underling disease (P=0.023) and the duration of the therapy (P=0.046) were significantly associated with efficacy. Multivariate analysis showed that the independent prognostic factor was the duration of combination antifungal therapy (OR=0.229, 95% CI 0.061- 0.863, P=0.029). The response rates of echinocandin combined with azole, echinocandin combined with amphotericin B and azole combined with amphotericin B were 81.8%, 60.0% and 82.6%, respectively (P>0.05), and 12-week survival rates were 81.8%, 80.0% and 86.5%, respectively (P>0.05). The drug- related adverse reactions occurred 59 times in 34 patients. BUN increasing, hypokalemia and abnormal liver functions were considered the main side effects.

CONCLUSIONFor IFD in children with hematologic disease, to extend the duration of treatment (≥ 14 days) could significantly improve the curative effect. Combinations of echinocandin with azole, echinocandin with amphotericin B and azole with amphotericin B can be used as a combination treatment options. Combination of Azole with amphotericin B is efficacious, safe and economic treatment option considering efficacy, survival rate, cost and dosage form.

Amphotericin B ; administration & dosage ; therapeutic use ; Antifungal Agents ; administration & dosage ; therapeutic use ; Child ; Drug Therapy, Combination ; Echinocandins ; administration & dosage ; therapeutic use ; Hematologic Diseases ; microbiology ; Humans ; Mycoses ; drug therapy ; Retrospective Studies ; Survival Rate ; Treatment Outcome

With the development of high gravity brewing, yeast cells are exposed to multiple brewing-associated stresses, such as increased osmotic pressure, enhanced alcohol concentration and nutritional imbalance. These will speed up yeast autolysis, which seriously influence beer flavor and quality. To increase yeast anti-autolytic ability, FKS1 overexpression strain was constructed by 18S rDNA. The concentration of β-1,3-glucan of overexpression strain was 62% higher than that of wild type strain. Meantime, FKS1 overexpression strain increased anti-stress ability at 8% ethanol, 0.4 mol/L NaCl and starvation stress. Under simulated autolysis, FKS1 showed good anti-autolytic ability by slower autolysis. These results confirms the potential of FKS1 overexpression to tackle yeast autolysis in high-gravity brewing.
Autolysis ; Beer ; Echinocandins ; genetics ; Glucosyltransferases ; genetics ; Hypergravity ; Membrane Proteins ; genetics ; Saccharomyces cerevisiae ; cytology ; Saccharomyces cerevisiae Proteins ; genetics

Drug Therapy, Combination ; Echinocandins ; administration & dosage ; therapeutic use ; Humans ; Invasive Pulmonary Aspergillosis ; complications ; drug therapy ; Lipopeptides ; Liver Failure ; complications ; drug therapy ; microbiology ; Male ; Middle Aged ; Voriconazole ; administration & dosage ; therapeutic use

BACKGROUNDNowadays, there are published trials in regards to the comparison of caspofungin with liposomal amphotericin B (L-AmB). However, these studies have a modest sample size and convey inconclusive results. The aim of this study was to review the efficacy and safety of caspofungin for the treatment of invasive fungal infections (IFIs), compared with L-AmB.

METHODSElectronic databases (up to July 31, 2013) PubMed and Embase databases, the Cochrane Library, and Google Scholar were searched to identify relevant trials of caspofungin and L-AmB. Analyses of efficacy and adverse outcomes were performed by relative risks (RRs) and 95% confidence intervals (CIs). Heterogeneity was assessed by χ(2)-test and the I(2)-statistic.

RESULTSThree trials were included in this meta-analysis with 1249 modified intention-to-treat (MITT) patients. The results showed that caspofungin produced equal efficacy in favorable overall response (RR = 1.02, 95% CI 0.88-1.18; P = 0.81) and mortality rate (RR = 1.53, 95% CI 0.38-6.27, P = 0.55), safer in clinical adverse events (RR = 0.20, 95% CI 0.08-0.54; P = 0.001), laboratory adverse events (RR = 0.69, 95% CI 0. 57-0.84; P = 0.0002), and discontinuation rate (RR = 0.26, 95% CI 0.08-0.83, P = 0.02), compared with L-AmB in the treatment of patients with IFIs.

CONCLUSIONBased on the results of this meta-analysis, it would appear that caspofungin was measured to have equal efficacy in clinical outcomes and safer in terms of adverse events.

Amphotericin B ; therapeutic use ; Antifungal Agents ; therapeutic use ; Echinocandins ; therapeutic use ; Febrile Neutropenia ; drug therapy ; Humans ; Lipopeptides ; Mycoses ; drug therapy