Describe The Metabolic Pathway Of L. Lactis

The enzyme lactate dehydrogenase (LDH) catalyzes the last step of anaerobic glycolysis that is important for the normal function of the body. Purification of LDH is essential to understand its structure and function. The purpose of this experiment was to extract and purify LDH enzyme from chicken muscle tissue using a variety of various. Analytical methods such as activity and protein assay were employed to determine the presence and purity of LDH. The cells were initially disrupted and proteins were solubilized. LDH was purified from the ammonium sulfate precipitated protein mixture by affinity chromatography and its activity was studied by

Enzymes are types of proteins that work as a substance to help speed up a chemical reaction (Madar & Windelspecht, 104). There are three factors that help enzyme activity increase in speed. The three factors that speed up the activity of enzymes are concentration, an increase in temperature, and a preferred pH environment. Whether or not the reaction continues to move forward is not up to the enzyme, instead the reaction is dependent on a reaction’s free energy. These enzymatic reactions have reactants referred to as substrates. Enzymes do much more than create substrates; enzymes actually work with the substrate in a reaction (Madar &Windelspecht, 106). For reactions in a cell it is

Yeast is a fungus that can generate glucose into energy without using any oxygen molecules. We tested the fermenting ability of yeast from two different carbon sources: glucose and aspartame. We hypothesized that yeast is unable to use the carbon sources of aspartame. To do this, we decided to use both carbon sources in the same concentration. Each carbon source was mixed with the same amount of yeast solution. The experiment group of 5.5 mM aspartame solution was compared with the control group of 5.5mM glucose solution. We recorded the rate of fermentation for glucose and aspartame in the Vernier Lab Quest. The fermentation rate of aspartame is a negative number, and glucose is a positive number. Our results show that yeast was unable to ferment aspartame as yeast fermented glucose. The results indicate that aspartame has no effect on yeast fermentation rate because yeast do not catabolize aspartame because it does not have the appropriate enzymes to break it down.

Lactic acid fermentation: Plant and fungal cells produce alcohol as a result of fermentation and animal cells produce lactic acid

One of the most significant reactions in Glycolysis is reaction one which involves the phosphorylation of glucose to form glucose-6-phosphate. Through the transfer of the hydrolysis of ATP, this supplies energy for the reaction and makes it essentially irreversible, having a negative free energy change, which allows for a spontaneous reaction in cells. Although the preparatory phase is energy consuming and uses up 2 ATP, the pay off phase synthesizes 4 molecules of ATP, with the transfer of 4e- via 2 hydride ions to 2 molecules of NAD+. Therefore, a net gain of 2 ATP is achieved through the glycolytic pathway alone. Following the glycolytic pathway, due to the absence of oxygen, as oxygen cannot be supplied fast enough to undergo aerobic respiration, the athlete will instead, undergo lactic acid fermentation. Lactic acid fermentation involves pyruvate that is formed from the glycolytic pathway to be reduced to lactate, with the aid of the enzyme, lactate dehydrogenase, while the coenzyme Nicotinamide Adenine Dinucleotide (NADH) is oxidised to NAD+. The product NAD+ then re-enters the glycolytic pathway in order to produce 2 ATP. This process of lactic acid fermentation produces 2 ATP for each cycle, and thus, rapidly supplies the body with a small amount of energy. However, with the buildup of lactic acid in the body, the athlete will eventually encounter the feeling of discomfort as this accumulation of lactate causes the body to

During this experiment, sugar sources were varied and respiration rate evaluated. To begin, a water bath was set at 30 degrees Celsius. This creates an optimum temperature for the enzymes in yeast to breakdown sugar and give off CO₂. Each sugar source, glucose, sucrose, lactose and glycerol were all added to its own unique yeast sample, one at a time. Each sugar source that was added to the yeast solution was immediately incubated for 10 min, then was transferred to a respiration chamber. The CO₂ sensor was put in, recording the CO₂ respiration for 4 min. This process was done for each sugar source. The reparation rate was recorded through Logger Pro. After 4 min passed, the slope was recorded, resulting in respiration rate.

Lactose is a sugar that can be put into smaller molecules, glucose and galactose. Lactose is when you are not able to digest milk and dairy meaning that the enzyme lactase that breaks down lactose is not functioning properly. ONPG was used as a substitute for lactase because even though it is colorless it helps show enzyme activity by turning yellow. This experiment measured the absorbance ONPG when exposed to lactase within an environment of different salinity’s. The enzyme, lactase, was obtained by crushing a lactaid pill and then was added into four cuvettes. ONPG and salt solution of different concentrations were added and their levels of absorption was measured by a spectrophotometer. The results showed that higher salt concentrations have a lower level of absorption. There were 4 cuvettes and within those cuvettes that solutions within them were being tested and the results showed the more salt solution added with the lactase the lower the absorbance. The less salt solution there was a higher rate of absorbance. The data supported the hypothesis that with increasing NaCl concentration there would be a decrease in enzyme activity.

“Enzymes are proteins that have catalytic functions” [1], “that speed up or slow down reactions”[2], “indispensable to maintenance and activity of life”[1]. They are each very specific, and will only work when a particular substrate fits in their active site. An active site is “a region on the surface of an enzyme where the substrate binds, and where the reaction occurs”[2].

12. One mechanism where lactate can be utilized as an energy source is it can be taken in by mitochondria and then be directly oxidized. A second mechanism can be in it being transported in a lactate shuttle towards other cells so it can be oxidized. Finally the third mechanism can be the lactate being transported through the blood towards the liver so it can then be reconverted from lactate to pyruvic

The metabolism of E. coli can occur in the glucose first instead of the lactose. Since, E. coli cannot metabolize lactose at all time since lactose could not always be available in the environment sometimes. Moreover, the production of proteins o costs energy and materials. Glucose is metabolized first compared to some other sugars since it provides a better source of energy than lactose. Not only that glucose is an example monosaccharide while lactose is a example of disaccharide whereas the lactose is not able to be utilized first as the cells is not able to transport and cleaves the disaccharide lactose. In other words, after the metabolism of the glucose would b exhausted then only the lactose utilisation would be synthesized by using enzyme

The metabolic pathway of various clostridia (C. acetobutylicum, C. beijerinckii and C. pasteurianum) is very similar (Zheng et al., 2009). The broadly studied clostridium species (C. acetobutylicum) produces three major classes of end products during fermentation such as (a) solvents (acetone, butanol and ethanol); (b) organic acids (acetic acid, butyric acid and lactic acid); (c) gases (carbon dioxide, and hydrogen). The biosynthesis of acetone, butanol, and ethanol share the same metabolic pathway as that of glucose to acetyl-CoA, but branches into different pathways thereafter (Fig. 5-1http://link.springer.com/article/10.1007/s10295-009-0609-9/fulltext.html - Fig1).

The results of the experiment vary from what is reported by previous studies (Curry, 2013, Enattah et al., 2002, & Tishkoff, 2007). The experiment was conducted on students currently in the Biology 225 course in Schenectady, NY. The class was primarily composed of individuals whom are descendants of Europe. Therefore, an assumption was made that by in large, the percentage of lactase persistent in the class that was expected was going to be near 95% (Curry, 2013). However, such a high percentage was not found. Of the class, only 49.3% of individuals were determined to possess a genotype that results in a phenotype of lactase persistence. Conversely, 40.8% of the class was found to carry the genotype lct/lct which results in the phenotype of lactase non-persistence. Therefore, the results are nearly 50% off from what we expected initially. This could be for numerous reasons, but perhaps the assumption should not have been made. The results fit much better when compared to the world average occurrence of lactase persistence. Curry notes that out of all individuals over the age of 8 years old, only 35% still possess the ability to digest and breakdown the lactose in dairy products (2013). The results do fit closer to the world average, therefore indicating that the assumption may have been wrong, the results of the experiment still do not necessarily indicate whether the total population of students in the Spring 2016 Biology 225 class fits the societal model where there is a

L bulgaricus has shown the ability to cause homofermentation of lactic acid, meaning the lactic acid produced is the on byproduct. In a study conducted by (wheater ,1974) the strains of l bulgaricus grow optimally at temperatures between 45 and 50 degrees Celsius and they do not prefer environments high in salt concentrations

Sugars are vital to all living organisms. The eukaryotic fungi, yeast, have the ability to use some, but not all sugars as a food source by metabolizing sugar in two ways, aerobically, with the aid of oxygen, or anaerobically, without oxygen. The decomposition reaction that takes place when yeast breaks down the hydrocarbon molecules is called cell respiration. As the aerobic respiration breaks down glucose to form viable ATP, oxygen gas is consumed and carbon dioxide is produced. This lab focuses on studying the rate of cellular respiration of saccharomyces cerevisiae, baker’s yeast, in an aerobic environment with glucose, sucrose, lactose, artificial sweetener, and water as a negative control. A CO2

In industrial scale production, microorganism such as bacteria and fungi was fully expressed the lipase. The advantage of using bacteria producing