Dataset Information

Aerobic deconstruction of cellulosic biomass by an insect-associated Streptomyces.

ABSTRACT: Streptomyces are best known for producing antimicrobial secondary metabolites, but they are also recognized for their contributions to biomass utilization. Despite their importance to carbon cycling in terrestrial ecosystems, our understanding of the cellulolytic ability of Streptomyces is currently limited to a few soil-isolates. Here, we demonstrate the biomass-deconstructing capability of Streptomyces sp. SirexAA-E (ActE), an aerobic bacterium associated with the invasive pine-boring woodwasp Sirex noctilio. When grown on plant biomass, ActE secretes a suite of enzymes including endo- and exo-cellulases, CBM33 polysaccharide-monooxygenases, and hemicellulases. Genome-wide transcriptomic and proteomic analyses, and biochemical assays have revealed the key enzymes used to deconstruct crystalline cellulose, other pure polysaccharides, and biomass. The mixture of enzymes obtained from growth on biomass has biomass-degrading activity comparable to a cellulolytic enzyme cocktail from the fungus Trichoderma reesei, and thus provides a compelling example of high cellulolytic capacity in an aerobic bacterium.

SUBMITTER: Takasuka TE

PROVIDER: S-EPMC3538285 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Aerobic deconstruction of cellulosic biomass by an insect-associated Streptomyces.

Takasuka Taichi E TE Book Adam J AJ Lewin Gina R GR Currie Cameron R CR Fox Brian G BG

Scientific reports 20130107

Streptomyces are best known for producing antimicrobial secondary metabolites, but they are also recognized for their contributions to biomass utilization. Despite their importance to carbon cycling in terrestrial ecosystems, our understanding of the cellulolytic ability of Streptomyces is currently limited to a few soil-isolates. Here, we demonstrate the biomass-deconstructing capability of Streptomyces sp. SirexAA-E (ActE), an aerobic bacterium associated with the invasive pine-boring woodwasp ...[more]

PMID: 23301151

Similar Datasets

Project description:Wood-decay fungi contain the cellular mechanisms to decompose such plant cell wall components as cellulose, hemicellulose, and lignin. A multi-omics approach to the comparative analysis of wood-decay fungi gives not only new insights into their strategies for decomposing recalcitrant plant biomass, but also an understanding of how to exploit these mechanisms for biotechnological applications. We have developed an analytical workflow, Applied Biomass Conversion Design for Efficient Fungal Green Technology (ABCDEFGT), to simplify the analysis and interpretation of transcriptomic and secretomic data. ABCDEFGT utilizes self-organizing maps for grouping genes with similar transcription patterns, and an overlay with secreted proteins. The key feature of ABCDEFGT is simple graphic outputs of genome-wide transcriptomic and secretomic topographies, which enables visual inspection without a priori of the omics data and facilitates discoveries of co-regulated genes and proteins. Genome-wide omics landscapes were built with the newly sequenced fungal species Pycnoporus coccineus, Pycnoporus sanguineus, and Pycnoporus cinnabarinus grown on various carbon sources. Integration of the post-genomic data revealed a global overlap, confirming the pertinence of the genome-wide approach. ABCDEFGT was evaluated by comparison with the latest clustering method for ease of output interpretation, and ABCDEFGT gave a better biological representation of fungal behaviors. The genome-wide multi-omics strategy allowed us to determine the potential synergy of particular enzymes decomposing cellulose, hemicellulose, and lignin such as Lytic Polysaccharide Monooxygenases, modular enzymes associated with a cellulose binding module1, and Class II Peroxidase isoforms co-regulated with oxido-reductases. Overall, ABCDEFGT was capable of visualizing genome-wide transcriptional and secretomic profiles for intuitive interpretations and is suitable for exploration of newly-sequenced organisms.

Project description:The cellulolytic insect symbiont bacterium, Streptomyces sp. SirexAA-E (SirexAA-E), is known to secrete a suite of Carbohydrate Active enZymes (CAZymes) for plant cell wall degradation in response to the available carbon sources. In this study, we sought to examine a poorly understood response of this bacterium to mannan, one of the major components of the plant cell wall, particularly in pine trees, the preferred host for SirexAA-E. SirexAA-E grew well on glucose, mannose, carboxymethyl cellulose (CMC), and locust bean gum (LBG) as sole carbon sources in the culture medium. The secreted proteins from each culture supernatant were tested for the polysaccharide-degrading ability, and the composition of secreted CAZymes in each culture supernatant were determined by LC-MS/MS. The results indicated that mannose, LBG, and CMC induced the secretion of mannan and cellulose-degrading enzymes. We found two α-1,2-mannosidases that were secreted during growth on mannose and LBG. By genomic analysis, we found a unique 12 bp palindromic sequence motif (5’-GACAACGTTGTC-3’) at 4 locations in the SirexAA-E genome, two of which were found upstream of genes encoding the above-mentioned α-1,2-mannosidases, along with a newly identified novel mannose and mannobiose responsive transcriptional regulator, SsManR. Furthermore, a transcriptional repressor that we previously showed was responsive to cellobiose, SsCebR, was determined to also use mannobiose as an effector ligand by in vitro binding assays. To test whether mannobiose induces the sets of genes under control of the two regulators, SsManR and SsCebR, SirexAA-E was grown on mannobiose, and the secretome composition was analyzed. As hypothesized, the composition of the mannobiose secretome combined sets of CAZymes found in both LBG and CMC secretomes, and so are likely under the regulation of both SsManR and SsCebR. To summarize, our findings support a transcriptional network that regulates mannose and LBG utilizing genes in SirexAA-E. Overall, this study defines a novel mannose regulatory transcriptional network that enables SirexAA-E to aggressively hydrolyze mannan-containing wood materials.

Dataset Information

Aerobic deconstruction of cellulosic biomass by an insect-associated Streptomyces.

Publications

Aerobic deconstruction of cellulosic biomass by an insect-associated Streptomyces.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets