Selected highlights of scientific publications, technology developments and partnerships.

SCIENCE

Impact of the Melle-Boinot process on the enhancement of second-generation ethanol production by Spathaspora passalidarum

AUG-2020 Microbial biodiversity is a source of solutions in biotechnology. The non-conventional yeast Spathaspora passalidarum is a potential platform for industrial applications aiming to produce cellulosic ethanol and biochemicals due to its natural ability to ferment xylose. This study reports for the first time the use of the Melle-Boinot fermentation process using this yeast, achieving high ethanol yields, demonstrating to be a worthy strategy in the production of biofuels.

SCIENCE

A rationally identified marine GH1 Beta-glucosidase has distinguishing functional features for simultaneous saccharification and fermentation

AUG-2020 New solutions to produce biofuels from sugarcane residues can come from unexpected environments, such as the marine. This work demonstrated the potential use of a marine enzyme β-glucosidase (GH1), rationally identified, in the production of cellulosic ethanol with simultaneous saccharification and fermentation. With activity in celo-oligosaccharides and efficiency in milder temperatures, this enzyme can be used in industrial biotechnological processes that involve the deconstruction of lignocellulosic material.

SCIENCE

Novel xylose transporter Cs4130 expands the sugar uptake repertoire in recombinant Saccharomyces cerevisiae strains at high xylose concentrations

AUG-2020 A major challenge on 2G technologies establishment is the inefficient assimilation of the five-carbon sugar xylose by engineered S. cerevisiae strains, increasing fermentation time. This work describes a novel and efficient xylose transporter, improving xylose uptake especially in high concentrations. The work also investigates the dynamic behavior of the transporter, pointing out residues related to xylose translocation.

SCIENCE

Enzymes knuckle down to the job

JUN-2020 Discovery of new enzymes for health, nutrition, biofuels, and other industrial biotechnological applications. Inspired by the molecular biodiversity of microorganisms this work has deepened the knowledge about new enzymatic strategies for the polysaccharides β-1,3-glucans processing, discovering a new mechanism of polysaccharide recognition and new mode of enzymatic action.

TECHNOLOGY

SUCRE Final Report

JUN-2020 Decarbonization of the electricity sector can benefit from straw, an underutilized sugarcane residue. This report provides an integrated and in-depth analysis of straw-based electricity in Brazil, considering technical, economic, environmental, and societal impacts. Corroborating its relevance to other sugarcane producing countries, SUCRE was a highlight in the report “South-South and Triangular Cooperation on the Bioeconomy“ presented at COP-25.

SCIENCE

Technoeconomic and life-cycle analysis of single-step catalytic conversion of wet ethanol into fungible fuel blendstocks

JUN-2020 Sustainable biofuels are important for decarbonization of hard-to-abate sectors such as aviation, shipping and heavy-duty road transportation. The low cost of ethanol and large production capacity make it attractive to be converted into a hydrocarbon fuel, which is typically done in three steps. This work goes further and describes an economic and environmental analysis of a renewable aviation fuel obtained from a single-step catalytic process using ethanol from biomass as raw material, reducing the need for external hydrogen.

SCIENCE

Substrate and Product-Assisted Catalysis: Molecular Aspects behind Structural Switches along Organic Hydroperoxide Resistance Protein Catalytic Cycle

MAY-2020 Quantum and classical simulations of structurally resolved proteins can further the understanding of biocatalysis in biological systems susceptible to damage by oxidants. This work provides insights on the oxidation response of bacteria cells by investigating the role of the active site and the catalytic pathways to decompose oxidants in Ohr proteins. This is relevant to the identification of inhibitors with therapeutic potential.

SCIENCE

Crystal structure of a novel xylose isomerase from Streptomyces sp. F-1 revealed the presence of unique features that differ from conventional classes

MAY-2020 Biofuels from sugarcane residues require yeasts to metabolize pentoses from xylose and to operate at mild conditions. This is a challenge to enzymatic conversion of xylose to xylulose that can be addressed by reversible changes of enzyme configurations. This work reports two new and unique xylose isomerases with amino-acid substitutions in the catalytic interface and preference for isomerization at milder conditions. Molecular understanding of enzymes can contribute to customization of fermentation processes.

TECHNOLOGY

Process simulation of renewable electricity from sugarcane straw: Techno-economic assessment of retrofit scenarios in Brazil

MAY-2020 Brazil can further reduce greenhouse gas emissions by significantly increasing renewable electricity generated from biomass. This is due to environmental legislation that has progressively prohibited burning before sugarcane harvesting and led to high availability of straw. This work integrates both agricultural and industrial models to provide techno-economic assessments that can enable retrofit investments in existing biorefineries. It highlights the strong dependence on electricity prices of straw recovery projects.

SCIENCE

Rational engineering of the Trichoderma reesei RUT-C30 strain into an industrially relevant platform for cellulase production

MAY-2020 Sustainable biofuels are important for decarbonization of light-vehicle road transportation. Synthetic biology was used to develop a microbial platform for cellulase production to reduce the cost of cellulosic ethanol production. This work describes a Brazilian technology validated at industrial operating conditions, which employs rational design of a public domain strain for cellulosic on-site manufacture of enzymes for ethanol production from sugarcane residues.

SCIENCE

Structural insights into β-1,3-glucan cleavage by a glycoside hydrolase family

MAY-2020 Discovery of new enzymes for health, nutrition, biofuels, and other industrial biotechnological applications. Inspired by the molecular biodiversity of microorganisms this work has deepened the knowledge about new enzymatic strategies for the polysaccharides β-1,3-glucans processing, discovering a new mechanism of polysaccharide recognition and new mode of enzymatic action.

TECHNOLOGY

Engineering aspects of hydrothermal pretreatment: From batch to continuous operation, scale-up and pilot reactor under biorefinery concept

MAR-2020 Sustainable biofuels are important for decarbonization of light-vehicle road transportation. Hydrothermal pre-treatment is considered one of the most promising technologies for cellulosic ethanol production. This review provides comprehensive information on hydrothermal pretreatment, including performance at semi-industrial scale (LNBR pilot plant) and discusses integrated process design.

PARTNERSHIP

Spatially remote motifs cooperatively affect substrate preference of a ruminal GH26-type endo-β-1,4-mannanase

MAR-2020 Enzymes can improve digestibility of mannan oligosaccharides present in cattle diets. Thus, cattle rumen contains a microbial community highly adapted to breakdown of lignocellulosic biomass. This work, with a partnering company, indicates a novel, complex and cooperative mechanism between enzyme subsites and ancillary domain to modulate substrate preference. It furthers the molecular understanding of substrate binding and recognition in the GH26 family and exhibits potential industrial use.

TECHNOLOGY

Comparison of Biofuel Life Cycle Analysis Tools

SEP-2019 Life cycle assessment (LCA) is a tool to assess the environmental impacts of a product. LCA model differences challenge credibility of individual evaluations applied to greenhouse gas mitigation targets. This work, in partnership with the International Energy Agency, compares greenhouse gas emissions for cellulosic ethanol production using internationally accepted LCA models from Brazil, Canada, USA and the EU. It provides recommendations to promote transparency and harmonization of LCA models.