I currently taking Bioprecess Engineering class. Our term project is to understa

Question

I currently taking Bioprecess Engineering class.

Our term project is to understand metabolic behavior under various environmental conditions (e.g., different carbon sources), and/or suggest metabolic engineering targets for strain improvement in terms of better cell growth or overproduction of products by using any available FBA tools (e.g., OptFlux) and relevant simulations.

And our target mircrobes is Mus Musculus (House Mouse).

Do you have any suggestion on what condition will the mus musculus grow better. And also how to increase urea prodcution of the microbes? Thank You

Explanation / Answer

Ans:- The  African lungfish Protopterus dolloi possesses carbamoyl phosphate III (CPS III) in the liver and not carbamoyl phosphate I (CPS I) also in the mouse Mus musculus. Hepatic arginase of P. dolloi is present mainly in the cytosol. Glutamine synthetase activity is present in both the mitochondrial and cytosolic fractions of the liver of P. dolloi. Therefore, we conclude that P. dolloi is a more primitive extant lungfish, which is intermediate between aquatic fish and terrestrial tetrapods, and represents a link in the fish-tetrapod continuum. During 6 days of aerial exposure, the ammonia excretion rate in P. dolloi decreased significantly to 8-16% of the submerged control. However, there were no significant increases in ammonia contents in the muscle, liver or plasma of specimens exposed to air for 6 days. These results suggest that

(1). endogenous ammonia production was drastically reduced and

(2). endogenous ammonia was detoxified effectively into urea. Indeed, there were significant decreases in glutamate, glutamine and lysine levels in the livers of fish exposed to air, which led to a decrease in the total free amino acid content. This indirectly confirms that the specimen had reduced its rates of proteolysis and/or amino acid catabolism to suppress endogenous ammonia production. Simultaneously, there were significant increases in urea levels in the muscle (8-fold), liver (10.5-fold) and plasma (12.6-fold) of specimens exposed to air for 6 days. Furthermore, there was an increase in the hepatic ornithine-urea cycle (OUC) capacity, with significant increases in the activities of CPS III (3.8-fold), argininosuccinate synthetase + lyase (1.8-fold) and, more importantly, glutamine synthetase (2.2-fold). This is the first report on the upregulation of OUC capacity and urea synthesis rate in an African lungfish exposed to air. Upon re-immersion, the urea excretion rate increased 22-fold compared with that of the control specimen, which is the greatest increase among fish during emersion-immersion transitions and suggests that P. dolloi possesses transporters that facilitate the excretion of urea in water.

Related Questions

Navigate

• Browse (All)
• Browse I
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.