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Biological Chemistry

Beta Glucosidase Activity Assay

I have followed the procedure that you provided to determine the activity of the beta-glucosidase, however, what I am unsure of is how the rate is calculated? In order for me to establish the rate, I followed your instructions however incubated the enzyme/buffer and PNPG solution for different times, ranging from 0-16 minute

Effect on PAGE gel

Describe the effects the following would have on the way you PAGE gel would run: a) Increasing the percent of acrylamide b) Increasing the pH of the Tris-glycine buffer to 9.5 c) Decreasing the voltage at which the gel was run d) Increasing the voltage at which the gel was run by a factor of 3 e) Doubling the sample load vo

Tripalmitoylglycerol Oxidation

Contrary to the legend camels do not store water in their humps, which actually consist of a large fat deposit. How can these fat deposits serve as a source of water? Calculate the amount of water (in liters) that can be produced by the camel from 1 kg (0.45 lb) of fat. Assume for simplicity that the fat consists entirely

Hydrolyzed gelatin use in diet

A weight-reducing diet heavily promoted in the past required the daily intake of "liquid protein" (soup of hydrolyzed gelatin), water and an assortment of vitamins. All other food and drink were to be avoided. People on this diet typically lost 10-14 lb in the first week. (a) Opponents argued that the weight loss was al

Fatty acid biosynthesis

Using your knowledge of fatty acid biosynthesis, provide an explanation for the following experimental observations: (a) The addition of uniformly labeled [14C] acetyl-CoA to a soluble liver fraction yields palmitate uniformly labeled with 14C. (b) However, the addition of a trace of uniformly labeled [14C]acetyl-CoA in th

Oxaloacetate and Oxygene Consumption

Addition of small amounts of oxaloacetate or malate to suspensions of minced pigeon-breast muscle stimulated the oxygen consumption of the preparation. Surprisingly, when the amount of oxygen consumed was measured, it was about 7 times more than the amount necessary to oxidize the added oxaloacetate or malate completely to carbo

Experiment: Measurement And Analysis Of Cellular Respiration

Cellular respiration is a process that occurs in many organisms. The rate of cellular respiration can be measured using several different methods. a) design a specific experiment to measure the rate of cellular respiration in an organism of your choice b) construct a graph to report your results and graph the results th

Absorption Spectra for Fluorescent Proteins

What is the difference between an absorption spectrum, excitation spectrum, and emissions spectrum? I deduce the identity of two fluorescent protein (label FP3 and FP6) based on absorption spectrum. The results of the absorption spectra were plotted in two ways: Y-axis as true absorbance or Y-axis as normalized absorbance

Calcium Signaling in Fertilization

Describe a well-controlled experiment to determine if the rise in internal free calcium observed in the cytoplasm of unfertilized sea urchin eggs in the presence of A23187 is due to in flux of calcium from seawater. Include experimental treatments, controls, and briefly describe experimental methods. Note: As mentioned in th


1. A "constitutive" process is one that is always present or active, whereas an "inducible" process is one that requires some stimulus or event to trigger its activity. In your journal, name and briefly explain two constitutive parts or processes that protect vertebrates from elements of their external environment. 2. Injec

Fluoroacetate and the citric acid cycle

Why does fluoracetate cause citrate to build up in the Citric Acid Cycle? Why do glucose and glycolysis decrease and hexose increases? Why is it fatal? What about fluoroacetyl-SCoA instead in the CAC? Why is it blocking or inhibiting?


Are yeasts better anaerobic or aerobic? Why?

Breakdown of glycogen

What is the difference between glycogen breakdown in liver and in muscle? - Release vs. consumption

Features of Chymotrypsin

How do I sketch the active site, including the catalytic triad? How do these three residue act to allow proteolysis? Can you briefly explain to me the features of the chymotrypsin active site and the mechanism?

Describing pH, pKa and Ionization

I need help with the following correlation: In the simplest terms possible, please. Describe how one would use the concepts of pH and pka to predict the ionization state of any given amino acid or its side chain in a protein.

Universal Priming Sequences

A 2500 base-pair long cDNA of unknown sequence was cloned into the MCS of a plasmid vector that has universal priming sequences adjacent to and on both sides of the MCS. On one side this is called the "forward universal priming sequence" and on the other it is called the "reverse universal priming sequence." Sanger sequencing

Using the data given in table below plot a Lineweaver-Burk plot

A) Using the data given in table below plot a Lineweaver-Burk plot b) Determine the Km and Vmax for the three sets of data c) Which inhibitor would the most effective at high substrate concentrations? d) Explain you choice Table 1 : Kinetics data for an enzyme catalysed reaction with and without the presence of

Maximum Growth Rate

Calculate the maximum growth rate (umax) and the specific growth rate (u) at t=10h dX/dt = unetX, when u is constant lnX-lnX0 = ut Attached is a word doc with the data

Tripeptide Properties

Tripeptide1: Tyr-Lys-Met Tripeptide2: Gly-Pro-Arg Tripeptide3: Asp-Trp-Tyr Tripeptide4: Asp-His-Glu Tripeptide5: Leu-Val-Phe Which one of the above tripeptides: a. is most negatively charged at pH7 b. contains the largest number of nonpolar R groups c. contains sulfur d. will have the greatest light absorbance at 280

Glycolysis Pathway questions

1) Glycerol can enter the glycolysis pathway by being converted to what? 2) How many molecules of ATP are used up in the glycolysis pathway? 3) How many pyruvate molecules are obtained from one molecule of glucose in the glycolysis pathway? 4) How many molecules of ATP are produced in the glycolysis pathway? 5) H

Saturation of Lipids - Bromine

If you add 1 drop of 5% bromine solution in hexane to 1mL each of 5% solution of lard, olive oil, and corn oil dissolved in hexane, what happens to the bromine that causes each mixture to turn colorless? If you continue adding drops of bromine to each, eventually the lipids change color. For our experiment it took 14 for lard

Saponification Water-Based Solutions

1) Since calcium and magnesium salts of fatty acids are insoluble in water, how would you expect this to affect the usefulness of soap in hard water? 2) If you were to make soap (using 4 grams of lard, 2 mL of 7.8 M sodium hydroxide & boiling it) and add it to the following and inverting, what would you expect to see as far

4 Problems

3 . Describe the role of each member of the "triad" in the mechanism of chymostrypsin. 4. Some enzymes show a bell shaped curve for enzyme activity versus pH. What conclusions can you reach about the nature and the function of groups in the enzyme? Name an enzyme which exhibits this characteristic. 7. In 1935, two famous

Biochemical pathway

You are studying a biochemical pathway in the bread mold NEUROSPORA crassa that is involved in the production of the compound C. You know that compounds A,B,D,E,F are required in this pathway, but you do not know the order in which they are synthesized. In order to study this, you isolate five auxotrophic strains that cannot syn

Synthesized triglycerides structural formulas

A normal well fed animal is given an intravenous injection of radioactive acetate labeled with 14C in the methyl group. By use of structural formulas indicate the carbon atoms that will be labeled most heavily in the newly synthesized triglycerides. Briefly justify your result.

NMR Spectrum and 13C Label

I need some help with this challenging question: 13C-NMR spectroscopy was used to detect (13)C-label accumulation in cerebral metabolites following the intravenous infusion of [1,6-(13)C]-glucose (Glc). The (1)H- [(13)C]-NMR method yielded high-quality (1)H-[(13)C]-NMR spectra. As a result, the (13)C labeling of [4-(13)C]-glut

Comparing Rates of CO2 Generation

The relative metabolic activities in an organism of glycolysis + the citric acid cycle vs. the pentose phosphate pathway + gluconeogenesis can be measured by comparing rates of 13CO2 generation upon administration of glucose labeled with 13C at C1 with that of glucose labeled at C6. Explain why this is possible.

Comparing Efficiency of Glucose Oxidation

Compare the relative efficiencies (in ATP's per mole of glucose oxidized) of glucose oxidation via glycolysis + the citric acid cycle vs. glucose oxidation via the pentose phosphate pathway + gluconeogenesis. Assume that NADH and NADPH are each energetically equivalent to three ATP's.