Answer:
Since high ethanol is a major stress during ethanol fermentation, ethanol-tolerant yeast strains are highly desirable for ethanol production on an industrial scale. A technology called global transcriptional machinery engineering (gTME), which exploits a mutant SPT15 library that encodes the TATA-binding protein of Saccharomyces cerevisiae (Alper et al., 2006; Science 314: 1565-1568), appears to be a powerful tool. to create ethanol tolerant strains. However, the ability of the strains created to tolerate high ethanol content in rich media remains to be demonstrated. In this study, a similar strategy was used to obtain five strains with higher ethanol tolerance (ETS1-5) of S. cerevisiae. When comparing the global transcriptional profiles of two selected strains ETS2 and ETS3 with that of the control, 42 genes that were commonly regulated with a double change were identified. Of the 34 deletion mutants available in an inactivated gene library, 18 were sensitive to ethanol, suggesting that these genes were closely associated with tolerance to ethanol.
Explanation:
Eight of them were novel and most were functionally unknown. To establish a basis for future industrial applications, the iETS2 and iETS3 strains were created by integrating the SPT15 mutant alleles of ETS2 and ETS3 into the chromosomes, which also exhibited increased tolerance to ethanol and survival after ethanol shock in a rich medium. Fermentation with 20% glucose for 24 h in a bioreactor revealed that iETS2 and iETS3 grew better and produced approximately 25% more ethanol than a control strain. The performance and productivity of ethanol also improved substantially: 0.31 g / g and 2.6 g / L / h, respectively, for the control and 0.39 g / g and 3.2 g / L / h, respectively, for iETS2 and iETS3.
Therefore, our study demonstrates the utility of gTME in generating strains with increased tolerance to ethanol that resulted in increased ethanol production. Strains with increased tolerance to other stresses such as heat, fermentation inhibitors, osmotic pressure, etc., can be further created using gTME.
Answer:
Spinal cord is a colon of nerve tissue that runs from the base of the skull to the center of the back.
Its function is to act as a highway communication between the body and the brain.
Explanation:
<span>True. Pure water is pH 7 (neutral).</span>
The correct answer is - physically dettering herbivory, protection from frost, and minimizing evaporation.
The plants have developed multiple traits that help them in multiple different circumstances, and some of those traits are the thorns and the hairs on their steams and leaves.
The thorns primarily serve for protection of the plant. They are very sharp and give a painful sting (occasionally poisonous one), so they are a physical protection from the herbivores that would try to eat parts of the plants.
The hairs have multiple functions. They are like a coat that helps the plant to not be affected by frost, help to stop the evaporation, and also partially manage to stop most of the insects that feed on plants.