Project description:The filamentous fungus Aspergillus oryzae is an important microbial cell factory for industrial production of useful enzymes, such as α-amylase. In order to optimize the industrial enzyme production process, there is a need to understand fundamental processes underlying protein production, here under how protein production links to metabolism through global regulatory structures. In this study, two α-amylase-producing strains of A. oryzae, a wild type strain and a transformant strain containing additional copies of the α-amylase gene, were characterized at a systematic level. Based on integrated analysis of ome-data together with genome-scale metabolic network and flux calculation, we identified key genes, key enzymes, key proteins, and key metabolites involved in the processes of protein synthesis and secretion, nucleotide metabolism, and amino acid metabolism that can be the potential targets for improving industrial protein production. Keywords: Two Aspergillus oryzae strains and two different carbon sources
Project description:The filamentous fungus Aspergillus oryzae is an important microbial cell factory for industrial production of useful enzymes, such as α-amylase. In order to optimize the industrial enzyme production process, there is a need to understand fundamental processes underlying protein production, here under how protein production links to metabolism through global regulatory structures. In this study, two α-amylase-producing strains of A. oryzae, a wild type strain and a transformant strain containing additional copies of the α-amylase gene, were characterized at a systematic level. Based on integrated analysis of ome-data together with genome-scale metabolic network and flux calculation, we identified key genes, key enzymes, key proteins, and key metabolites involved in the processes of protein synthesis and secretion, nucleotide metabolism, and amino acid metabolism that can be the potential targets for improving industrial protein production. Keywords: Two Aspergillus oryzae strains and two different carbon sources Two carbon sources (glucose, maltose) with three biological replicates for A. oryzae strain A1560 and strain CF1.1
Project description:Genetic engineering of filamentous fungi has promise for accelerating the transition to a more sustainable food system and enhancing the nutritional value, sensory appeal, and scalability of microbial foods. However, genetic tools and demonstrated use cases for bioengineered food production by edible strains are lacking. Here, we developed a synthetic biology toolkit for Aspergillus oryzae, an edible fungus traditionally used in fermented foods and currently used in protein production and meat alternatives. Our toolkit includes a CRISPR-Cas9 method for genome integration, neutral loci, and new promoters. We use these tools to enhance the elevate levels of the nutraceutical ergothioneine and intracellular heme in the edible biomass. The biomass overproducing heme is red in color and is readily formulated into imitation meat patties with minimal processing. These findings highlight the promise of genetic approaches to enhance fungal meat alternatives and provide useful engineering tools for diverse applications in fungal food production and beyond.
Project description:In this study, we focused on chemically defined inducers or substrates to drive expression of cellulases, hemicellulases and accessory enzymes in the model filamentous fungus Aspergillus oryzae. Cellohexaose (O-CHE), mannohexaose (O-MHE), xylopentaose (O-XPE), arabinoheptaose (O-AHP), 1,3:1,4-β-glucohexaose (O-BGHEXA), 63-α-D-glucosyl-maltotriosyl-maltotriose (O-GMH), 61-α-D-galactosyl-mannotriose (O-GM3), xyloglucan (X3Glc4-borohydride reduced; O-X3G4R), turanose (TYR) and sophorose (SOP) were used to induce the plant polysaccharide degradation machinery of A. oryzae.
Project description:Vongsangnak2008 - Genome-scale metabolic
network of Aspergillus oryzae (iWV1314)
This model is described in the article:
Improved annotation through
genome-scale metabolic modeling of Aspergillus oryzae.
Vongsangnak W, Olsen P, Hansen K,
Krogsgaard S, Nielsen J.
BMC Genomics 2008; 9: 245
Abstract:
BACKGROUND: Since ancient times the filamentous fungus
Aspergillus oryzae has been used in the fermentation industry
for the production of fermented sauces and the production of
industrial enzymes. Recently, the genome sequence of A. oryzae
with 12,074 annotated genes was released but the number of
hypothetical proteins accounted for more than 50% of the
annotated genes. Considering the industrial importance of this
fungus, it is therefore valuable to improve the annotation and
further integrate genomic information with biochemical and
physiological information available for this microorganism and
other related fungi. Here we proposed the gene prediction by
construction of an A. oryzae Expressed Sequence Tag (EST)
library, sequencing and assembly. We enhanced the function
assignment by our developed annotation strategy. The resulting
better annotation was used to reconstruct the metabolic network
leading to a genome scale metabolic model of A. oryzae.
RESULTS: Our assembled EST sequences we identified 1,046 newly
predicted genes in the A. oryzae genome. Furthermore, it was
possible to assign putative protein functions to 398 of the
newly predicted genes. Noteworthy, our annotation strategy
resulted in assignment of new putative functions to 1,469
hypothetical proteins already present in the A. oryzae genome
database. Using the substantially improved annotated genome we
reconstructed the metabolic network of A. oryzae. This network
contains 729 enzymes, 1,314 enzyme-encoding genes, 1,073
metabolites and 1,846 (1,053 unique) biochemical reactions. The
metabolic reactions are compartmentalized into the cytosol, the
mitochondria, the peroxisome and the extracellular space.
Transport steps between the compartments and the extracellular
space represent 281 reactions, of which 161 are unique. The
metabolic model was validated and shown to correctly describe
the phenotypic behavior of A. oryzae grown on different carbon
sources. CONCLUSION: A much enhanced annotation of the A.
oryzae genome was performed and a genome-scale metabolic model
of A. oryzae was reconstructed. The model accurately predicted
the growth and biomass yield on different carbon sources. The
model serves as an important resource for gaining further
insight into our understanding of A. oryzae physiology.
This model is hosted on
BioModels Database
and identified by:
MODEL1507180056.
To cite BioModels Database, please use:
BioModels Database:
An enhanced, curated and annotated resource for published
quantitative kinetic models.
To the extent possible under law, all copyright and related or
neighbouring rights to this encoded model have been dedicated to
the public domain worldwide. Please refer to
CC0
Public Domain Dedication for more information.
Project description:The Aspergillus oryzae, an important filamentous fungus used in food fermentation and enzyme industry, has been revealed to own prominent features in its genomic compositions by genome sequencing and various other tools. However, the functional complexity of the A. oryzae transcriptome has not yet been fully elucidated. Here, we applied direct high-throughput paired-end RNA sequencing (RNA-Seq) to the transcriptome of A. oryzae under four different culture conditions and confirmed most of the annotated genes. Moreover, with high resolution and sensitivity afforded by RNA-Seq, we were able to identify a substantial number of novel transcripts, new exons, untranslated regions, alternative upstream initiation codons (uATGs) and upstream open reading frames (uORFs), which serves a remarkable insight into the A. oryzae transcriptome. We also were able to assess the alternative mRNA isoforms in A. oryzae and found a large number of genes undergoing alternative splicing. Many genes or pathways that might involve in higher levels of protein production in solid-state culture than in liquid culture were identified by comparing gene expression levels between different cultures. Our analysis indicated that the transcriptome of A. oryzae was much more complex than previously anticipated and the results might provide a blueprint for further study of A. oryzae transcriptome.
Project description:The Aspergillus oryzae, an important filamentous fungus used in food fermentation and enzyme industry, has been revealed to own prominent features in its genomic compositions by genome sequencing and various other tools. However, the functional complexity of the A. oryzae transcriptome has not yet been fully elucidated. Here, we applied direct high-throughput paired-end RNA sequencing (RNA-Seq) to the transcriptome of A. oryzae under four different culture conditions and confirmed most of the annotated genes. Moreover, with high resolution and sensitivity afforded by RNA-Seq, we were able to identify a substantial number of novel transcripts, new exons, untranslated regions, alternative upstream initiation codons (uATGs) and upstream open reading frames (uORFs), which serves a remarkable insight into the A. oryzae transcriptome. We also were able to assess the alternative mRNA isoforms in A. oryzae and found a large number of genes undergoing alternative splicing. Many genes or pathways that might involve in higher levels of protein production in solid-state culture than in liquid culture were identified by comparing gene expression levels between different cultures. Our analysis indicated that the transcriptome of A. oryzae was much more complex than previously anticipated and the results might provide a blueprint for further study of A. oryzae transcriptome. mRNA expression of Aspergillus oryzae in 4 different culture conditions was determined by method of RNA-Seq using short reads from high throughput sequencing technology.
Project description:A. niger and A. oryzae are two filamentous fungi widely used in industry to produce various enzymes (e.g. pectinases, amylases) and metabolites (e.g. citric acid). Using proteomics, the co-cultivation of these two fungi in wheat bran showed an equal distribution of the two strains forming mixed colonies with a broad range of carbohydrate active enzymes produced. This stable mixed microbial system seems suitable for subsequent commercial processes such as enzyme production. XlnR knock-out strains for both aspergilli were used to study the influence of plant cell wall degrading enzyme production on the fitness of the mixed culture.
Project description:Hypoxia imposes a challenge upon most of the filamentous fungi that require oxygen for proliferation. Here, we used whole genome DNA microarrays to investigate global transcriptional changes in Aspergillus nidulans gene expression after exposure to hypoxia followed by normoxia. Aeration affected the expression of 2,864 genes (27% of the total number of genes in the fungus), of which 50% were either induced or repressed under hypoxic conditions. Up-regulated genes included those for glycolysis, ethanol production, the tricarboxylic acid (TCA) cycle, and for the γ-aminobutyrate (GABA) shunt that bypasses two steps of the TCA cycle. Ethanol and lactate production under hypoxic conditions indicated that glucose was fermented to these compounds via the glycolytic pathway. Since the GABA shunt bypasses the NADH-generating reaction of the TCA cycle catalyzed by oxoglutarate dehydrogenase, hypoxic A. nidulans cells eliminated excess NADH. Hypoxia down-regulated some genes involved in transcription initiation by RNA polymerase II, and lowered the cellular mRNA content. These functions were resumed by reoxygenation, indicating that A. nidulans controls global transcription to adapt to a hypoxic environment. This study is the first to show that hypoxia elicits systematic transcriptional responses in A. nidulans.