The ability of pathogenic microorganisms to assimilate essential nutrients from their hosts is critical for pathogenesis. Here we report endothelial zinc sequestration by the major human fungal pathogen, Candida albicans. We hypothesised that, analogous siderophore-mediated iron acquisition, C. albicans utilises an extracellular scavenger acquiring this metal. postulated that such a "zincophore" system would consist secreted factor with zinc-binding properties, which can specifically...

Propionate is used to protect bread and animal feed from moulds. The mode of action this short‐chain fatty acid was studied using Aspergillus nidulans as a model organism. filamentous fungus able grow slowly on propionate, which oxidized acetyl‐CoA via propionyl‐CoA, methylcitrate pyruvate. inhibits growth A. glucose but not acetate; the latter shown inhibit propionate oxidation. When grown synthase deletion mutant much more sensitive towards presence in medium compared wild‐type accumulates...

Acryloyl-CoA reductase from Clostridium propionicum catalyses the irreversible NADH-dependent formation of propionyl-CoA acryloyl-CoA. Purification yielded a heterohexadecameric yellow-greenish enzyme complex [(alpha2betagamma)4; molecular mass 600 +/- 50 kDa] composed dehydrogenase (alpha2, 2 x 40 kDa) and an electron-transferring flavoprotein (ETF; beta, 38 kDa; gamma, 29 kDa). A flavin content (90% FAD 10% FMN) 2.4 mol per alpha2betagamma subcomplex (149 was determined. substrate...

The pathway of the oxidation propionate to pyruvate in Escherichia coli involves five enzymes, only two which, methylcitrate synthase and 2‐methylisocitrate lyase, have been thoroughly characterized. Here we report that isomerization (2 S ,3 )‐methylcitrate R )‐2‐methylisocitrate requires a novel enzyme, dehydratase (PrpD), well‐known aconitase (AcnB), tricarboxylic acid cycle. AcnB was purified as 2‐methylaconitate hydratase from E. cells grown on identified by its N‐terminus. enzyme has an...

The fungal pathogens Aspergillus fumigatus and Candida albicans are major health threats for immune-compromised patients. Normally, macrophages neutrophil granulocytes phagocytose inhaled conidia in the two-dimensional (2-D) environment of alveolar lumen or growing tissue microabscesses, which composed a three-dimensional (3-D) extracellular matrix. However, neither cellular dynamics, per-cell efficiency, outcome this interaction, nor environmental impact on process known. Live imaging shows...

ABSTRACT Aspergillus fumigatus is the main cause of invasive aspergillosis in immunocompromised patients, and only a limited number drugs for treatment are available. A screening method new antifungal compounds urgently required, preferably an approach suitable vitro vivo studies. Bioluminescence imaging powerful tool to study temporal spatial resolutions infection effectiveness drugs. Here, we describe construction bioluminescent A. strain by fusing promoter glyceraldehyde-3-phosphate...

Invasive bronchopulmonary aspergillosis (IBPA) is a life-threatening disease in immunocompromised patients. Although Aspergillus terreus frequently found the environment, A. fumigatus by far main cause of IBPA. However, once establishes infection host, as fatal infections. Thus, we hypothesized that initial steps establishment might be fundamentally different between these two species. Since alveolar macrophages represent one first phagocytes facing inhaled conidia, compared interaction and...

Recently, the Aspergillus terreus terrein gene cluster was identified and selected for development of a new heterologous expression system. The encodes specific transcription factor TerR that is indispensable induction. To identify binding sites, different recombinant versions DNA-binding domain were analyzed motif recognition. high affinity consensus TCGGHHWYHCGGH from genes required production site mutations confirmed their essential contribution to in A. terreus. A combination with its...

Abstract Penicillium roqueforti is used worldwide in the production of blue-veined cheese. The blue-green colour derives from pigmented spores formed by fungal growth. Using a combination bioinformatics, targeted gene deletions, and heterologous expression we discovered that pigment formation was due to DHN-melanin biosynthesis pathway. Systematic deletion pathway genes altered arising spore colour, yielding white yellow-green red-pink-brown phenotypes, demonstrating potential generate new...

Invasive aspergillosis is a life-threatening disease mainly caused by the fungus Aspergillus fumigatus. In immunocompromised individuals conidia are not efficiently inactivated, which can end in invasive fungal growth. However, metabolic requirements of hardly known. Earlier investigations revealed an accumulation toxic propionyl-CoA methylcitrate synthase mutant, when grown on propionyl-CoA-generating carbon sources. During growth could derive from proteins, released infected host tissues....

Invasive aspergillosis (IA) is a major cause of infectious morbidity and mortality in immune compromised patients. Studies on the pathogenesis IA have been limited by difficulty to monitor disease progression real-time. For real-time monitoring infection, we recently engineered bioluminescent A. fumigatus strain. In this study, demonstrate that bioluminescence imaging can track at different anatomic locations murine model recapitulates natural route infection. To define temporal functional...

ABSTRACT Infection models are essential tools for studying microbial pathogenesis. Murine considered the “gold standard” in vivo infections caused by Aspergillus species, such as A. fumigatus . Recently developed molecular protocols allow rapid construction of high numbers fungal deletion mutants, and alternative infection based on cell culture or invertebrates widely used screening mutants to reduce number rodents animal experiments. To bridge gap between invertebrate mice, we have an...

ObjectivesCandida albicans is an important fungal pathogen that can cause life-threatening disseminated infections. To determine the efficacy of therapy in murine models, a determination renal burden as cfu commonly used. However, this approach provides only snapshot current situation individual animal and cryptic sites infection may easily be missed. Thus, we aimed to develop real-time non-invasive imaging monitor vivo.

Secondary metabolites have a great potential as pharmaceuticals, but there are only few examples where regulation of gene cluster expression has been correlated with ecological and physiological relevance for the producer. Here, signals, mediators, biological effects terrein production were studied in fungus Aspergillus terreus to elucidate contribution competition. Terrein causes fruit surface lesions inhibits plant seed germination. Additionally, is moderately antifungal reduces ferric...

Nitrogen is one of the key nutrients for microbial growth. During infection, pathogenic fungi like C. albicans need to acquire nitrogen from a broad range different and changing sources inside host. Detecting available adjusting expression genes their uptake degradation therefore crucial survival growth as well establishing an infection. Here, we analyzed transcriptional response starvation feeding with infection-relevant arginine bovine serum albumin (BSA), representing amino acids...

Aspergillus nidulans was used as a model organism to investigate the fungal propionate metabolism and mechanism of growth inhibition by propionate. The fungus is able grow slowly on sole carbon energy source. Propionate oxidized pyruvate via methylcitrate cycle. key enzyme synthase purified corresponding gene mcsA , which contains two introns, cloned, sequenced overexpressed in A. . derived amino acid sequence shows more than 50% identity those most eukaryotic citrate synthases, but only 14%...

Methylcitrate synthase is a key enzyme of the methylcitrate cycle and required for fungal propionate degradation. Propionate not only serves as carbon source, but also acts food preservative (E280-283) possesses negative effect on polyketide synthesis. To investigate metabolism from opportunistic human pathogenic fungus Aspergillus fumigatus, was purified to homogeneity characterized. The displayed both, citrate activity showed similar characteristics corresponding nidulans. coding region A....