Autor(es)

Silvello, Maria Augusta de Carvalho ; Teixeira, Gleidson Silva ; Bueno, Danilo ; Goldbeck, Rosana

• Tipo de documento: Artigo Científico
• Fonte: ALGAL RESEARCH-BIOMASS BIOFUELS AND BIOPRODUCTS; v. 90, p. 9-pg., 2025-08-01.

Resumo

The production of third-generation (3G) ethanol from microalgae-derived carbohydrates requires a cost-effective hydrolysis strategy and a robust fermenting microorganism. In this study, the amyA gene encoding alpha-amylase from Aspergillus tubingensis was integrated into the genome of the thermotolerant Saccharomyces cerevisiae JAYET strain using CRISPR/Cas9. JAYET was previously derived from the industrial PE-2 strain and engineered for cellulase production. The CRISPR/Cas9 system enabled efficient genome editing and construction of a synthetic yeast strain, named JAYCA. The performance of the engineered strain was evaluated under different fermentation strategies (SHF, SSF, pSSF), temperatures (30 degrees C and 40 degrees C), and compared with parental strains. JAYCA showed strong growth on starch agar, confirming successful expression of extracellular alpha-amylase. During fermentation of carbohydrate-rich Chlorella vulgaris biomass, JAYCA achieved 92.1 % of the theoretical ethanol yield using Separate Hydrolysis and Fermentation (SHF) at 30 degrees C. The highest ethanol concentration (16.41 g & sdot;L- 1) was obtained under Simultaneous Saccharification and Fermentation (SSF), combining alpha-amylase and amyloglucosidase activity. These results demonstrate that the engineered yeast effectively converted microalgal carbohydrates into ethanol, achieving high 3G ethanol titers through an eco-friendly Consolidated Bioprocessing (CBP) strategy based on enzymatic hydrolysis and renewable biomass. This is the first report of applying the engineered JAYCA strain in a microalgae-based CBP strategy for 3G ethanol production. (AU)

• Processo FAPESP: 15/20630-4 - Desenvolvimento integrado de biorrefinaria e planta de bioetanol de cana-de-açúcar com emissão zero de CO2: rotas para converter recursos renováveis em bioprodutos e bioeletricidade
• Beneficiário: Rubens Maciel Filho
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 18/20787-9 - Estratégias para sacarificação de biomassa microalgal visando a produção de bioetanol 3G
• Beneficiário: Maria Augusta de Carvalho Silvello
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 22/08607-0 - Produção de oligossacarídeos por enzimas de expressão heteróloga: avaliação das propriedades funcionais e análise técnico-econômica
• Beneficiário: Danilo Bueno
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado