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Clinical Microbiology: Open Access | ISSN: 2327-5073 | Volume: 7
Microbiology: Education, R&D and Market
7
th
Annual Summit on
September 28-29, 2018 | San Antonio, USA
Comparative metabolomics and proteomics between
Saccharomyces cerevisiae
hybrids after adaptive
evolution in the lignocellulosic substrate for bioethanol production
Thalita Peixoto Basso
University of Sao Paulo, Brazil
I
n the search for alternative sources to fossil fuels, biofuels, such as bioethanol, are shown highly efficient. However, due to
ethical issues regarding the use of foods such as sugar and corn in ethanol production, research has been carried out in search
of by-products, such as lignocellulosic residues, which can be used in the production of bioethanol. Sugarcane bagasse is a
promising by-product that can be used for this purpose, to be available in the plant, does not require transportation expenses,
relatively be abundant and cheap. Nevertheless, lignocellulosic hydrolyzate from bagasse is constituted of non-naturally
metabolizable sugars by
Saccharomyces cerevisiae
(employed microorganism for ethanol production), and the presence of
inhibitors against microorganisms responsible for fermentation, as hydroxymethylfurfural, furfural and acetic acid formed
during acid pretreatment of bagasse. The challenge of this work was to circumvent these difficulties through the use of
S.
cerevisiae
hybrids tolerant to inhibitors found in the substrate for second-generation ethanol (2GE) production in Brazil. Such
hybrids had been obtained in previous work by massal and direct crossings of mutagenized
S. cerevisiae
followed by adaptive
evolution. These hybrids were genetically engineered with the cassette X123 containing the three genes responsible for xylose
metabolism (xylose reductase, xylitol dehydrogenase, and xylulokinase), and then were followed by adaptive evolution (in YPX
and hydrolysate media) in search of an optimal strain for pentose and hexose simultaneous fermentation. Therefore, the objective
was to obtain strains with the potential of industrial use in the production of 2GE from sugarcane bagasse. The evolved strain
was compared with the original by evaluating their physiological and technological traits. The proteomic and metabolomic
analysis was performed in order to better understand the metabolic basis of any improvement observed.
tpbasso@usp.brClin Microbiol 2018, Volume: 7
DOI: 10.4172/2327-5073-C3-040