The typical samples on day 0 and day 18 were chosen and were studied by GC-MS. After that, the volatile compounds were identified by comparing the retention times and mass spectra of the sample with those found in the mass spectrometer database NIST or in literature. Journal overview. Special Issues. Academic Editor: Xiuxiu Sun. Received 26 Feb Revised 22 Apr Accepted 04 May Published 25 May Materials and Methods 2.
Different superscript letters in the row indicate that the differences are significant LSD test,. Trace indicates that the concentration of the compound is below the detectable level. Table 1. Although there is some divergence of the three curves at longer times, the sucrose curve is always as high as or higher than the glucose and fructose curves.
The observation that the total amount of CO 2 released at the end is not the same for the three sugars may be due to the purity of the fructose and glucose samples not being as high as that of the sucrose. Next, we decided to investigate how the rate of fermentation depends on the concentration of the sugar. It can be seen that the initial rate of CO 2 mass loss is the same for the Of course the total amount of CO 2 given off by the Later, we repeated this experiment using sucrose in place of glucose and obtained the same result.
Comparison of the mass of CO 2 released vs time for the fermentation of Each sugar sample was dissolved in mL of water and then 7. After seeing that the rate of yeast fermentation does not depend on the concentration of sugar under the conditions of our experiments, we decided to see if it depends on the concentration of the yeast.
We took two The results are shown in Fig. It can clearly be seen that the rate of CO 2 release does depend on the concentration of the yeast. The slope of the sample with 7. We repeated the experiment with sucrose and fructose in place of glucose and obtained similar results. Comparison of the mass of CO 2 released vs time for the fermentation of two One had 7. In hindsight, the observation that the rate of fermentation is dependent on the concentration of yeast but independent of the concentration of sugar is not surprising.
Enzyme saturation can be explained to students in very simple terms. A molecule such as glucose is rather small compared to a typical enzyme. The large molecular ratio of sugar to enzyme clearly means that every enzyme site is occupied by a sugar molecule. Thus, doubling or halving the sugar concentration cannot make a significant difference in the initial rate of the reaction. On the other hand, doubling the concentration of the enzyme should double the rate of reaction since you are doubling the number of enzyme sites.
The experiments described here are easy to perform and require only a balance good to 0. The results of these experiments can be discussed at various levels of sophistication and are consistent with enzyme kinetics as described by the Michaelis-Menten model.
For enzyme reactions such as this, the reaction does not take place if the temperature is too high because the enzymes get denatured. The effect of pH and salt concentration can also be investigated. Skip to main Skip to footer. April Introduction Enzyme catalysis 1 is an important topic which is often neglected in introductory chemistry courses.
Fermentation rate of sucrose, lactose alone, and lactose with lactase Fig. Coevolution trumps pleiotropy: carbon assimilation traits are independent of metabolic network structure in budding yeast PLoS One 8 e Physiological studies in aerobic batch cultivations of Saccharomyces cerevisiae strains harboring the MEL1 gene Biotechnol Bioeng 68 9.
Two glucose transporters in Saccharomyces cerevisiae are glucose sensors that generate a signal for induction of gene expression P Natl Acad Sci USA 93 Expression of the SUC2 gene of Saccharomyces cerevisiae is induced by low levels of glucose Yeast 13 Top Curr Chem Vol.
How did Saccharomyces evolve to become a good brewer? Trends Genet 22 6. Co-consumption of sugars or ethanol and glucose in a Saccharomyces cerevisiae strain deleted in the HXK2 gene Yeast 18 Characterization of the glycosylation sites in yeast external invertase J Biol Chem Production of the antimalarial drug precursor artemisinic acid in engineered yeast Nature 3.
Crystallization and preliminary X-ray diffraction analysis of the invertase from Saccharomyces cerevisiae Acta Crystallogr F 68 Three-dimensional structure of Saccharomyces invertase: role of a non-catalytic domain in oligomerization and substrate specificity J Biol Chem Trends Plant Sci 8 63 9.
Salerno GL Measurement of enzymes related to sucrose metabolism in permeabilized Chlorella vulgaris cells Physiol Plant a 64 Salerno GL Occurrence of sucrose and sucrose metabolizing enzymes in a chlorophyllous algae Plant Sci b 42 5 8.
Temperature adaptation markedly determines evolution within the genus Saccharomyces Appl Environ Microb 77 Metabolic variation in natural populations of wild yeast Ecol Evol 5 Uptake of sucrose by Saccharomyces cerevisiae Arch Biochem Biophys Proline accumulation in baker's yeast enhances high-sucrose stress tolerance and fermentation ability in sweet dough Int J Food Microbiol 40 3.
Schneiter R What are yeasts? Smirnoff N The carbohydrates of bryophytes in relation to desiccation tolerance J Bryol 17 Industrial fuel ethanol yeasts contain adaptive copy number changes in genes involved in vitamin B1 and B6 biosynthesis Genome Res 19 8. Effect of glycosylation on yeast invertase oligomer stability J Biol Chem Pyrosequencing reveals regional differences in fruit-associated fungal communities Environ Microbiol 16 Darling Biomedical Library.
Two structural hardware frames with associated physiological software packages in dicotyledons? J Exp Bot 50 An interlaboratory comparison of physiological and genetic properties of four Saccharomyces cerevisiae strains Enzyme Microb Technol 26 Spatial population expansion promotes the evolution of cooperation in an experimental prisoner's dilemma Curr Biol 23 Microbial export of lactic and 3-hydroxypropanoic acid: implications for industrial fermentation processes Metab Eng 6 KGaA 81 Energetics of Saccharomyces cerevisiae in anaerobic glucose-limited chemostat cultures J Gen Microbiol Effect of benzoic acid on metabolic fluxes in yeasts—a continuous-culture study on the regulation of respiration and alcoholic fermentation Yeast 8 Glucose and sucrose: hazardous fast-food for industrial yeast?
Trends Biotechnol 22 7. Reconstruction of ancestral metabolic enzymes reveals molecular mechanisms underlying evolutionary innovation through gene duplication PLoS Biol 10 e Surprisingly diverged populations of Saccharomyces cerevisiae in natural environments remote from human activity Mol Ecol 21 Carbon source dependent promoters in yeasts Microb Cell Fact 13 1 Energetics and kinetics of maltose transport in Saccharomyces cerevisiae : a continuous culture study Appl Environ Microb 59 9.
Fuel ethanol after 25 years Trends Biotechnol 17 7. Dynamic regulation of gene expression using sucrose responsive promoters and RNA interference in Saccharomyces cerevisiae Microb Cell Fact 14 InvertaseSuc2-mediatedinulincatabolism is regulated at the transcript level in Saccharomyces cerevisiae Microb Cell Fact 14 Oxford University Press is a department of the University of Oxford. It furthers the University's objective of excellence in research, scholarship, and education by publishing worldwide.
Sign In or Create an Account. Sign In. Advanced Search. Search Menu. Article Navigation. Close mobile search navigation Article Navigation. Volume Sucrose and Saccharomyces cerevisiae : a relationship most sweet. Oxford Academic. Vijayendran Raghavendran.
Boris Ugarte Stambuk. Andreas Karoly Gombert. Revision received:. Select Format Select format. Permissions Icon Permissions. Open in new tab Download slide. Table 1. Saccharomyces cerevisiae enzymes that hydrolyse sucrose. Reference and assay conditions. Open in new tab.
Table 2. Oxygen availability. Anaerobiosis a. Anaerobiosis b. Aerobiosis c. Aerobiosis d. Table 3. Parental strain relevant genotype. Selected achievement. Physiological and transcriptional responses to high concentrations of lactic acid in anaerobic chemostat cultures of Saccharomyces cerevisiae.
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Anomalies in the growth kinetics of Saccharomyces cerevisiae strains in aerobic chemostat cultures. De Kok. Increasing free-energy ATP conservation in maltose-grown Saccharomyces cerevisiae by expression of a heterologous maltose phosphorylase. Similarities and differences in the biochemical and enzymological properties of the four isomaltases from Saccharomyces cerevisiae. Characteristics of extracellular invertase of Saccharomyces cerevisiae in heterologous expression of the suc2 gene in Solanum tuberosum plants.
Glucose uptake kinetics and transcription of HXT genes in chemostat cultures of Saccharomyces cerevisiae. Microarray karyotyping of maltose fermenting Saccharomyces yeasts with differing maltotriose utilization profiles reveals copy number variation in genes involved in maltose and maltotriose utilization.
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Comparative molecular genetic analysis of the beta-fructosidases in yeast Saccharomyces. Sucrose utilization in budding yeast as a model for the origin of undifferentiated multicellularity. Improved use of a public good selects for the evolution of undifferentiated multicellularity.
The interaction of Saccharomyces paradoxus with its natural competitors on oak bark. Fructo-oligosaccharide synthesis by mutant versions of Saccharomyces cerevisiae invertase. Advances in Experimental Medicine and Biology. Glucose and sucrose act as agonist and mannose as antagonist ligands of the G protein-coupled receptor Gpr1 in the yeast Saccharomyces cerevisiae.
Microbe domestication and the identification of the wild genetic stock of lager-brewing yeast. Recurrent selection for sucrose content has altered growth and sugar accumulation in sugarcane.
Glucose repression in Saccharomyces cerevisiae is related to the glucose concentration rather than the glucose flux. Comparative genetics of yeast Saccharomyces cerevisiae. Chromosomal translocations carrying the SUC2 marker. Genetic variation of the repeated MAL loci in natural populations of Saccharomyces cerevisiae and Saccharomyces paradoxus. Polymeric SUC genes in natural populations of Saccharomyces cerevisiae. Genes affecting the regulation of SUC2 gene expression by glucose repression in Saccharomyces cerevisiae.
Progress in metabolic engineering of the yeast Saccharomyces cerevisiae. Production of biopharmaceutical proteins by yeast. Advances through metabolic engineering. Bloomberg Sustainability. Discrimination of Saccharomyces cerevisiae and Saccharomyces paradoxus strains by the SUC2 gene sequences. Discrimination of SUC gene from MAL -constitutive gene by the fermentability of fructooligosaccharide in the yeast Saccharomyces cerevisiae. Construction of a sucrose-fermenting baker's yeast incapable of hydrolysing fructooligosaccharides.
Scale up of fuel ethanol production from sugar beet juice using loofa sponge immobilized bioreactor. Coevolution trumps pleiotropy: carbon assimilation traits are independent of metabolic network structure in budding yeast. Physiological studies in aerobic batch cultivations of Saccharomyces cerevisiae strains harboring the MEL1 gene. Two glucose transporters in Saccharomyces cerevisiae are glucose sensors that generate a signal for induction of gene expression. Expression of the SUC2 gene of Saccharomyces cerevisiae is induced by low levels of glucose.
Presecretory and cytoplasmic invertase polypeptides encoded by distinct mRNAs derived from the same structural gene differ by a signal sequence. Heterosis is prevalent among domesticated but not wild strains of Saccharomyces cerevisiae. Sucrose biosynthesis in a prokaryotic organism: presence of two sucrose-phosphate synthases in Anabaena with remarkable differences compared with the plant enzymes.
Co-consumption of sugars or ethanol and glucose in a Saccharomyces cerevisiae strain deleted in the HXK2 gene. Genetic and phenotypic characteristics of baker's yeast: relevance to baking. Studies on identifying the catalytic role of Glu in the active site of yeast invertase.
Osmotic adjustment and organic solute accumulation in unicellular cyanobacteria from freshwater and marine habitats. Production of the antimalarial drug precursor artemisinic acid in engineered yeast. Crystallization and preliminary X-ray diffraction analysis of the invertase from Saccharomyces cerevisiae.
Three-dimensional structure of Saccharomyces invertase: role of a non-catalytic domain in oligomerization and substrate specificity. Measurement of enzymes related to sucrose metabolism in permeabilized Chlorella vulgaris cells. Occurrence of sucrose and sucrose metabolizing enzymes in a chlorophyllous algae. Temperature adaptation markedly determines evolution within the genus Saccharomyces. Natural populations of Saccharomyces kudriavzevii in Portugal are associated with oak bark and are sympatric with S.
Feedback between population and evolutionary dynamics determines the fate of social microbial populations. Enhanced pH and thermal stabilities of invertase immobilized on montmorillonite K Proline accumulation in baker's yeast enhances high-sucrose stress tolerance and fermentation ability in sweet dough.
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