Log in
Chemistry
2
answers
0
watching
121
views
11 Dec 2019

Protein X, a protein of the electron transport chain in the inner mitochondrial membrane, can be removed from cell debris by extraction with salt solution. In contrast, protein Y from the same source can be removed only by extraction into detergent solutions or organic solvents. What kind of membrane proteins are protein X and protein Y? Explain.

Watch
2
answers
0
watching
121
views

For unlimited access to Homework Help, a Homework+ subscription is required.

Unlock all answers

Get 1 free homework help answer.
Already have an account? Log in
Share
Jarrod Robel
Jarrod RobelLv2
13 Dec 2019
Already have an account? Log in
Share
discord banner image
Join us on Discord
Chemistry Study Group
Join now

Related textbook solutions

Basic Chemistry
5 Edition,
Timberlake
ISBN: 9780134138046
Principles of Chemistry Molecular Approach
4th Edition,
Tro
ISBN: 9780134112831
Principles of Chemistry Molecular Approach
3rd Edition, 2014
Tro
ISBN: 9780321971944
Chemistry: Structure and Properties
2nd Edition,
Tro
ISBN: 9780134293936
Chemistry: A Molecular Approach
3rd Edition,
Tro
ISBN: 9780321809247
Chemistry: A Molecular Approach
5th Edition,
Tro
ISBN: 9780134874371
Principles of Chemistry: A Molecular Approach
4th Edition,
Tro
ISBN: 9780134895741
Chemistry: The Central Science
14th Edition, 2017
Brown
ISBN: 9780134414232

Related questions

Please Help

Proteins and electrolytes can be transported into cells in two ways: either through diffusion through the plasma membrane, or facilitated diffusion through a channel. Some proteins or electrolytes can be transported through both mechanisms. We can make a simplified model of this by modeling two membranes in parallel with each other, and assuming 1D diffusion through both. Assume that protein A can be transported through the membrane in either method (i.e., direct diffusion or facilitated diffusion) (NOTE: this picture doesn’t really describe the system well. Imagine the red circles can move through the membrane AND/OR through the channel). Outside of the cell, the concentration of protein A is 100 nM. Inside the cell, the concentration is 10 nM. Assume the thickness of the plasma membrane is 10 nm. The diffusion constant for direct diffusion of Protein A in the membrane is 1x10^-10 cm2 /s, and the diffusion constant for facilitated diffusion is 5x10^-10 cm2 /s. The partition coefficient Φ for Protein A in the plasma membrane is 0.01, and the partition coefficient Φ for Protein A in the channel is 0.05.

A. Assume that initially the channel is closed, so Protein A can only get into the cell via direct diffusion through the membrane. Calculate the steady-state flux of Protein A across the membrane. Assume 1-D diffusion, steady state diffusion, and no convection.

B. Assume that the channel is now open, and acting in parallel to direct diffusion. Assume 1-D diffusion through both the membrane and the channel, assume steady state diffusion, and assume no convection.

C. Determine a general expression for the effective diffusion coefficient through the system in Part B, and show how these two pathways behave like resistors in parallel.

Enzyme X is a highly pigmented protein that imparts thecharacteristic color to certain blue-green algae. It alsofacilitates a reaction necessary to the survival of this species;we can follow the kinetics of this reaction by measuring theconversion of Substance X to Substance Y at various times duringpurification.
1. Given a pure preparation of these algae, and the requiredsupplies and equipment, devise and outline an empirical procedurefor purifying Enzyme X.
2. What is a good indication of purity in yourpreparation?

What I have:

The first step to determining protein identification andpurification is to isolate the protein of interest from thestarting material. This process is initiated by determining theproper assay to be used. An assay is a termed used to describe thetechnique that one uses in protein purification. It describesmethodology, protocol, and detailed technique unique to certainexperiments. In more detail, unique to certain experiments,describes the chemical properties of the desired protein. Theprotein of interest must be removed from the cell. Its associatedenzyme is a useful tool in determining its specific activity. Thisis a quantitative measurement that can assess the progression ofprotein purification. Proteins can be purified based on size,charge, solubility, and even binding affinity.

Given a pure preparation of algae and purifying Enzyme X, I wouldbegin by
extraction of all proteins via salting out technique. Then removethe supernatant and centrifuge, followed by column chromatographyto separate all the proteins based on size, followed by labelingvials according to size. Next, remove a small amount of what is ineach vial and add to it substance X. Because Y is unknown, I dependon the rate of substance X's depletion to detect the presence ofthe enzyme. After recording the change in concentration of X(through fluorescence change) per certain amount of time that isfixed regardless of what protein is being tested, I then identifythe vial that has the mix of proteins that has the most enzyme X,and run SDS-page electrophoresis. This provides an idea about thesize of the different proteins. The difference in their sizes isassessed via the column chromatography. Finally, I run just thatvial through the column and retest with substance X. This indicatespurity in the preparation.

my teachers reponse: what you have submitted is a start howeverthis is general protocol. The purpose of the assignment is tomake sure you the student understands the various proteinpurification techniques discussed in class and in the textbook andwrite a general protocol. The M1 assignment is being returnedto you again to refer back to topic section 1.2 within the classand see what is discussed. It specifically states in the commentary%u201CTo isolate a compound completely, the above methods, and manyothers not described, are usually employed sequentially, and thespecific activity is measured after each step. Only the fractioncontaining the highest specific activity is then passed on to thenext step.%u201D It is telling you the reader that all discussedneed to be done at a minimum to purify a protein and more steps areneeded that would be determined by first doing the%u2018general%u2019 steps as described. Also note that as writtenthe protocol submitted started purificaiton with whole cells - thatis not possible. The protein of interest is inside the cell - thefirst step is to get the protein of interest out of the cell, howis that done?

5. Almost all of the oxygen (O2) one consumes in breathing is converted to: a. acetyl-CoA. b. carbon dioxide (CO2). c. carbon monoxide and then to carbon dioxide. d. none of the above. e. water.

6. A new compound isolated from mitochondria is claimed to represent a previously unrecognized carrier in the electron transfer chain. It is given the name coenzyme Z. Which line of evidence do you feel is the least conclusive in assigning this compound a position in the electron transfer chain? a. Alternate oxidation and reduction of the mitochondrion-bound coenzyme Z can be readily demonstrated. b. Removal of coenzyme Z from the mitochondria results in a decreased rate of oxygen consumption. c. The rate of oxidation and reduction of mitochondrion-bound coenzyme is of the same order of magnitude as the overall rate of electron transfer in mitochondria as measured by oxygen consumption. d. The reduction potential of Z is between that of two compounds known to participate in the electron transport chain e. When added to a mitochondrial suspension, coenzyme Z is taken up very rapidly and specifically by the mitochondria.

7. Which of the following is not true of the citric acid cycle? a. All enzymes of the cycle are located in the cytoplasm, except succinate dehydrogenase, which is bound to the inner mitochondrial membrane. b. In the presence of malonate, one would expect succinate to accumulate. c. Oxaloacetate is used as a substrate but is not consumed in the cycle. d. Succinate dehydrogenase channels electrons directly into the electron transfer chain. e. The condensing enzyme is subject to allosteric regulation by ATP and NADH.

8. Conversion of 1 mol of acetyl-CoA to 2 mol of CO2 and CoA via the citric acid cycle results in the net production of: a. 1 mol of citrate. b. 1 mol of FADH2. c. 1 mol of NADH. d. 1 mol of oxaloacetate. e. 7 mol of ATP.

Weekly leaderboard

Home
Homework Help 3,900,000
Chemistry 830,000
Start filling in the gaps now
Log in