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Guadalajara, Mexico

Ramirez-Cordova J.,Medical and Pharmaceutical Biotechnology Unit | Drnevich J.,Urbana University | Madrigal-Pulido J.A.,Medical and Pharmaceutical Biotechnology Unit | Arrizon J.,Industrial Biotechnology Unit | And 3 more authors.
Antonie van Leeuwenhoek, International Journal of General and Molecular Microbiology | Year: 2012

During ethanol fermentation, yeast cells are exposed to stress due to the accumulation of ethanol, cell growth is altered and the output of the target product is reduced. For Agave beverages, like tequila, no reports have been published on the global gene expression under ethanol stress. In this work, we used microarray analysis to identify Saccharomyces cerevisiae genes involved in the ethanol response. Gene expression of a tequila yeast strain of S. cerevisiae (AR5) was explored by comparing global gene expression with that of laboratory strain S288C, both after ethanol exposure. Additionally, we used two different culture conditions, cells grown in Agave tequilana juice as a natural fermentation media or grown in yeast-extract peptone dextrose as artificial media. Of the 6368 S. cerevisiae genes in the microarray, 657 genes were identified that had different expression responses to ethanol stress due to strain and/or media. A cluster of 28 genes was found overexpressed specifically in the AR5 tequila strain that could be involved in the adaptation to tequila yeast fermentation, 14 of which are unknown such as yor343 c, ylr162 w, ygr182 c, ymr265 c, yer053 c-A or ydr415c. These could be the most suitable genes for transforming tequila yeast to increase ethanol tolerance in the tequila fermentation process. Other genes involved in response to stress (RFC4, TSA1, MLH1, PAU3, RAD53) or transport (CYB2, TIP20, QCR9) were expressed in the same cluster. Unknown genes could be good candidates for the development of recombinant yeasts with ethanol tolerance for use in industrial tequila fermentation. © Springer Science+Business Media B.V. 2012.

Herrera-Lopez E.J.,Industrial Biotechnology Unit
Methods in Molecular Biology | Year: 2012

Recent advances in the field of biology, electronics, and nanotechnology have improved the development of biosensors. A biosensor is a device composed of a biological recognition element and a sensor element. Biosensor applications are becoming increasingly important in areas such as biotechnology, pharmaceutics, food, and environment. Lipases and phospholipases are enzymes which have been used widely in food industry, oleochemical industry, biodegradable polymers, detergents, and other applications. In the medical industry, lipases and phospholipases are used as diagnostic tools to detect triglycerides, cholesterol, and phospholipids levels in blood samples. Therefore, the development of lipase and phospholipase biosensors is of paramount importance in the clinical area. This chapter introduces the reader into the preliminaries of biosensor and reviews recent developments of lipase and phospholipase biosensors. © 2012 Springer Science+Business Media New York.

Casas-Godoy L.,National Polytechnic Institute of Toulouse | Casas-Godoy L.,French National Center for Scientific Research | Casas-Godoy L.,French National Institute for Agricultural Research | Duquesne S.,National Polytechnic Institute of Toulouse | And 7 more authors.
Methods in Molecular Biology | Year: 2012

Lipases are ubiquitous enzymes, widespread in nature. They were first isolated from bacteria in the early nineteenth century and the associated research continuously increased due to the particular characteristics of these enzymes. This chapter reviews the main sources, structural properties, and industrial applications of these highly studied enzymes. © 2012 Springer Science+Business Media New York.

Sanchez-Gonzalez M.,Autonomous University of Nuevo Leon | Blanco-Gamez A.,Autonomous University of Nuevo Leon | Parra-Saldivar R.,Monterrey Institute of Technology | Mateos-Diaz J.C.,Industrial Biotechnology Unit | Estrada-Alvarado M.I.,Sonora Institute of Technology
Methods in Molecular Biology | Year: 2012

Recently, the crystal structure of the feruloyl esterase A from Aspergillus niger (AnFaeA) was elucidated. This enzyme displays an α/β hydrolase fold and a catalytic triad similar to that found in fungal lipases (30-37% identity). Surprisingly, AnFaeA showed an overall fold similarity with the Rhizomucor miehei and other related fungal lipases. All these data strongly suggest that the ancestral function (lipase) had shifted, with molecular adaptation leading to a novel enzyme (type-A feruloyl esterase). The discovery of new feruloyl esterases could lead to get insight into the evolutionary pathways of these enzymes and into new possibilities of directed evolution of lipases. In this chapter, the production of Bacillus flexus NJY2 feruloyl esterases is described. Unlike the previously described feruloyl esterases, which mostly belong to eukaryotes (mainly fungus), this unique feruloyl esterases from a prokaryotic alkaliphile microorganism could be the starting point for new discoveries on lipase and feruloyl esterase evolutionary relationships. © 2012 Springer Science+Business Media New York.

Castillo E.,National Autonomous University of Mexico | Torres-Gavilan A.,National Autonomous University of Mexico | Sandoval G.,Industrial Biotechnology Unit | Marty A.,National Polytechnic Institute of Toulouse | And 2 more authors.
Methods in Molecular Biology | Year: 2012

A basic insight on different thermodynamical strategies reported for the optimization of lipase-catalyzed reactions is presented. The significance of selecting the appropriate reaction media in order to enhance selectivity and operational stability of enzymes is discussed. From this analysis, the importance of developing thermodynamic strategies for controlling both the reaction kinetics and equilibrium is emphasized. A theoretical model (Conductor-like Screening Model for Realistic Solvation) for calculating thermodynamic properties in fluid phases is proposed as a powerful tool for predicting equilibrium and kinetic behavior in biocatalytic processes. © 2012 Springer Science+Business Media New York.

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