Team:Tec-Monterrey/projectoverview
From 2011.igem.org
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- | <p class="textojustif"> Every year, an average of 5.3 million tons of sugar are produced in Mexico. According the national statistical organizations, there are 12 million of Mexicans that depend economically from the production of sugar. Cane sugar mills are located in 15 states of the 32 Mexican states. The cities with sugar cane industrial activity have their infrastructure, services, culture and education based on | + | <p class="textojustif"> Every year, an average of 5.3 million tons of sugar are produced in Mexico. According to the national statistical organizations, there are 12 million of Mexicans that depend economically from the production of sugar. Cane sugar mills are located in 15 states of the 32 Mexican states. The cities with sugar cane industrial activity have their infrastructure, services, culture and education based on this industry. The sugar industry generates more than 450 thousand jobs and benefits 2.2 millions of people approximately. However, this isector is facing some arising problems: a decrease on the international sugar prices (<a href=" http://www.fao.org/docrep/008/y9492s/y9492s07.htm"> FAO & OECD </a>), and a decrease on internal consumption because of the replacement of sucrose by fructose and artificial sweeteners. After the NAFTA in 2008, high fructose corn syrup has no longer import tariff for its entrance to Mexico and is more industrially viable compared to sucrose. In this context, some opportunities can be detected in this industry: the diversification of the uses of sugar cane products and its sub-products, and the development of new technologies for more sustainability of sugar cane industry. |
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Inverted sugar contains fructose and glucose in equal proportions. This product has a greater demand than pure glucose as a food and drink sweetener due to many useful physical and functional attributes of fructose including sweetness, flavor enhancement, humectancy, color and flavor development, freezing-point depression, and osmotic stability. (Hanover LM & White JS, 1993). The implementation of new technology enable production of inverted sugar from sucrose, and the exploitation of sugarcane bagasse, which consists of 51.8% of cellulose, for the bio-fuel production for the Mexican sugar mills could approach in 3 principal areas: food, energy and environment. | Inverted sugar contains fructose and glucose in equal proportions. This product has a greater demand than pure glucose as a food and drink sweetener due to many useful physical and functional attributes of fructose including sweetness, flavor enhancement, humectancy, color and flavor development, freezing-point depression, and osmotic stability. (Hanover LM & White JS, 1993). The implementation of new technology enable production of inverted sugar from sucrose, and the exploitation of sugarcane bagasse, which consists of 51.8% of cellulose, for the bio-fuel production for the Mexican sugar mills could approach in 3 principal areas: food, energy and environment. | ||
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- | <p class="textojustif"> <i>Clostridium thermocellum</i> endoglucanase CelD is an enzyme that belongs to family E cellulases. Family E includes, beside <i>C.thermocellum</i> CelD, a number of cellulases such as <i>Butyrivibrio fibrisolvens</i> cellodextrinase Cedl, <i>C. thermocellum</i> endoglucanase CelF, <i>Cellulomonas fimi</i> endoglucanase CenB, <i>Clostridium stercorarium</i> Avicelase I, <i>Persea americana</i> endoglucanase, <i>Dictyostelium discoideum</i> endoglucanase, <i>Cellulomonas fimi</i> endoglucanase CenC, and <i>Pseudomonas fluorescens</i> var. cellulosa endoglucanase A. (cita). | + | <p class="textojustif"> For this approach, firstly a cellulase was considered for the new application of sugarcane bagasse. <i>Clostridium thermocellum</i> endoglucanase CelD is an enzyme that belongs to family E cellulases. Family E includes, beside <i>C.thermocellum</i> CelD, a number of cellulases such as <i>Butyrivibrio fibrisolvens</i> cellodextrinase Cedl, <i>C. thermocellum</i> endoglucanase CelF, <i>Cellulomonas fimi</i> endoglucanase CenB, <i>Clostridium stercorarium</i> Avicelase I, <i>Persea americana</i> endoglucanase, <i>Dictyostelium discoideum</i> endoglucanase, <i>Cellulomonas fimi</i> endoglucanase CenC, and <i>Pseudomonas fluorescens</i> var. cellulosa endoglucanase A. (cita). |
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- | <i>Zymomonas mobilis</i> is a gram negative bacterium that produces ethanol from glucose, fructose and sucrose (Swings & DeLey, 1977) at a rate three to four fold, and at a higher final yield compared to the traditionally used yeast strains (Rogers <i>et al</i>., 1982). Almost 60% of the extracellular sucrase activity of <i>Zymomonas mobilis</i> is the result of the activity of the extracellular SacC. Theat particular enzyme has a specific activity to hydrolysis sucrose of ¿? that is a high standard for sucrose. (¿?) It is a monomer in its native state, with a molecular weight of 46 kDa and has already been expressed in <i>E. coli</i>. (Gurunathan S & Gunasekaran P, 2004) | + | <i>The second enzyme was consisted of an invertase. Zymomonas mobilis</i> is a gram negative bacterium that produces ethanol from glucose, fructose and sucrose (Swings & DeLey, 1977) at a rate three to four fold, and at a higher final yield compared to the traditionally used yeast strains (Rogers <i>et al</i>., 1982). Almost 60 % of the extracellular sucrase activity of <i>Zymomonas mobilis</i> is the result of the activity of the extracellular SacC. Theat particular enzyme has a specific activity to hydrolysis sucrose of ¿......? that is a high standard for sucrose. (¿.....?) It is a monomer in its native state, with a molecular weight of 46 kDa and has already been expressed in <i>E. coli</i>. (Gurunathan S & Gunasekaran P, 2004) |
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- | + | Inverted sugar is conventionaly synthetizing by the acid hydrolysis of sucrose. However, such reaction has a low conversion efficiency and high-energy consumption (¿.....?). | |
- | Inverted sugar is conventionaly synthetizing by the acid hydrolysis of sucrose. However, such reaction has a low conversion efficiency and high-energy consumption ( | + | |
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- | + | As an alternative method to the traditional chemical process to produce inverted sugar, cell surface display was suggested. The cell surface display is a technique to display proteins on the surface of bacteria, fungi, or mammalian cells by fusing them to surface anchoring motifs. This technique has a wide range of biotechnological and industrial applications, including development of vaccines, peptide and antibody libraries, bioremediation, whole-cell-biosensors, and whole-cell-biocatalysis. When proteins are expressed in the outer membrane of <i>Escherichia coli</i> the cell envelope acts as their matrix. This display is achievable thanks to several displaying systems as outer membrane porins, lipoproteins, GPI-anchored-proteins, fimbriae, and autotransporters. (Jana S & Deb JK, 2005; Lee SH <i>et al</i>., 2004) Displaying proteins on the cell surface also makes preparing or purifying the protein unnecessary in many instances. Whole cells displaying the molecule of interest can be used in industrial process reactions or analytical assays and then can be simply recovered by centrifugation. (Joachim J & Meyer TF, 2007) | |
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The type V autotransporters are natural transportation system to import/export substrates through the periplasm/membrane. They are composed of an N-terminal sec-dependent signal peptide, a passenger domain, and a translocator domain that is predicted to form a β-barrel. (Rutherford <i>et al</i>., 2006) | The type V autotransporters are natural transportation system to import/export substrates through the periplasm/membrane. They are composed of an N-terminal sec-dependent signal peptide, a passenger domain, and a translocator domain that is predicted to form a β-barrel. (Rutherford <i>et al</i>., 2006) |