For a protein containing no -sheet secondary structure the CD spectrum gives[0] 222 = -29,750 deg.cm ?.decimole 1. Given from reference spectra that 100% helix has a[e] 222 = -36,000 deg.cm ?.decimole and 100% coil has a [0] 222 = +3,000 deg.cm 2.decimole 1a). What is the percentage alpha helical content of the protein? Show your working.b.) The protein and a short duplex oligonucleotide are added at equimolar concentration in abuffer containing 100 mM NaCl and then in a buffer containing 1 M NACI, the two samplesare analysed by CD. The spectra in the 250 to 280 nm region differs considerably betweenthe samples but the spectrums in the 200 – 230 nm range are similar. What hypothesis canyou form concerning the protein?

Circular dichroism is a spectroscopic technique to find out the secondary structure, folding and…

Answered: a). What is the percentage alpha…

Biochemistry

9th Edition

ISBN:9781319114671

Author:Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.

Publisher:Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.

Chapter1: Biochemistry: An Evolving Science

Section: Chapter Questions

Problem 1P

See similar textbooks

Similar questions

A sample mixture consists of three proteins with the following properties: Protein A MW (kDa) 200 Amino acid composition 40% nonpolar, 60% polar B 45 20% nonpolar, 80% polar C 98 85% nonpolar, 15% polar IpH 9 3 5 1. If the mixture is subjected to ammonium sulfate precipitation, which protein will precipitate out first? [Select] 2. If the mixture is subjected to isoelectric focusing, which protein will stop moving nearest to the positive electrode? [Select] 3. If the mixture is subjected to cation-exchange chromatography using a buffer at pH 7, which protein will bind to the resin? [Select] 4. If the mixture is subjected to SDS-PAGE, which protein will be at the bottommost portion of the gel? [Select] * Previous Nex
You have purified Protein 'X' and you want to know its concentration. As we learned, you can calculate concentrations by simply measuring UV280 absorbance of protein solutions. Using a UV spectrophotometer, you measured an absorbance of 0.6. Given that Protein X has an absorptivity (or extinction coefficient) of 0.2 mL•mg-cm at 280 nm, what is the concentration of purified protein solution (assume the light path is 1 cm)? -1 O A. 3 g/mL B. 3 mg/mL OC.0.2mg/mL OD.0.2 g/mL OE. 0.6 g/mL
On an SDS-gel, If the distance traveled by the bromophenol blue dye is 7 cm, and the distance traveled by the protein band is 2.8 cm, the mobility of the protein is 40 4 40% 0.4
1. Calculate the molecular weight of protein in sample A. Given the protein migration distance is 26 mm and the migration distance of the dye front (gel length) is 6.5 cm.
Protein A is made up of a single polypeptide chain; The molecular mass of A is 20,000 Da; the A molecule has 2 tryptophan residues, 5 tyrosine residues, and no disulfide bonds. Calculate what absorbance (at 280 nm) a solution of protein A will have at a concentration of 1.0 mg / mL, in a 1 cm cell. Write the calculations you have done.
2
You analyze a protein of 100 kDa using SDS-PAGE in the absence and presence of �-mercaptoethanol (BME) and observe the following band pattern in the gels: Which of the following statements about the protein is correct? (the image is attached) a. The protein consists of three polypeptide chains, two of which are connected via S-S bridges. b. The protein consists of two different polypeptide chains connected via S-S bridges. c. The protein has two different folding conformations. d. The protein consists of two different polypeptide chains linked to each other via non-covalent interactions.
Uracil and Adenine are two nitrogen bases constitutive of RNA. Both compounds show maximum absorption spectra at 260 nm. A 20 µmol.L-¹ uracil solution gives an absorbance value of 0.24 at 260 nm (in a 1 cm-optical path length cuvette). 1- Calculate the molar extinction coefficient of uracil at 260 nm. 2- A solution containing a mixture of unknown concentrations of adenine and uracil shows an absorbance value at 260 nm of 0.4 (1 cm-optical path length cuvette). Considering that the molar concentration of uracil is twice the one of adenine, and that the molar extinction coefficient of adenine at 260 nm is 16000 mol¹.L.cm-¹, calculate the molar concentrations of adenine and uracil in the mixture. -1
You have a soluble protein that is highly flexible and is only 23 kDa in size. What is the most suitable technique (X-ray crystallography, NMR, cryo-EM) for structure determination of this protein? Explain your reasoning.
Green fluorescent protein comprises a beta barrel with an alpha helix in the middle of the barrel. - How many strands make up the beta barrel? - Would you classify the beta sheet in this structure as parallel, antiparallel or mixed? Can you please explain why?
Some characteristics of three proteins are listed in the table below: Protein Molecular Weight (Da) Isoelectric point (pI) Does the Protein Contain a heme moiety? 1 25,000 4.5 Yes 2 77,500 10.8 No 3 75,000 4.9 No a) Could gel filtration chromatography be used to separate a mixture containing Protein 1 and 2? Clearly explain why or why not. If it can be used, which protein would elute last (clearly explain why)? After collecting the fractions from the column, the absorbance of each fraction will be measured using a spectrophotometer. Can both proteins 1 and 2 be monitored at 280nm and 400nm (clearly explain)? b) Which 2 proteins listed in the table above could be separated by ion exchange chromatography but NOT by gel filtration? Why? c) Which 2 proteins listed in the table above could be separated by gel filtration chromatography but NOT by ion exchange chromatography? Why?
A protein has an asp glu/arg lys ratio of 3. Explain how would the overall charge on this molecule likely be at pH 7 be negative?

SEE MORE QUESTIONS

Recommended textbooks for you

Biochemistry

ISBN:

9781319114671

Author:

Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.

Publisher:

W. H. Freeman

Lehninger Principles of Biochemistry

Biochemistry

ISBN:

9781464126116

Author:

David L. Nelson, Michael M. Cox

Publisher:

W. H. Freeman

Fundamentals of Biochemistry: Life at the Molecul…

Biochemistry

ISBN:

9781118918401

Author:

Donald Voet, Judith G. Voet, Charlotte W. Pratt

Publisher:

WILEY

Biochemistry

ISBN:

9781319114671

Author:

Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.

Publisher:

W. H. Freeman

Lehninger Principles of Biochemistry

Biochemistry

ISBN:

9781464126116

Author:

David L. Nelson, Michael M. Cox

Publisher:

W. H. Freeman

Fundamentals of Biochemistry: Life at the Molecul…

Biochemistry

ISBN:

9781118918401

Author:

Donald Voet, Judith G. Voet, Charlotte W. Pratt

Publisher:

WILEY

Biochemistry

ISBN:

9781305961135

Author:

Mary K. Campbell, Shawn O. Farrell, Owen M. McDougal

Publisher:

Cengage Learning

Biochemistry

ISBN:

9781305577206

Author:

Reginald H. Garrett, Charles M. Grisham

Publisher:

Cengage Learning

Fundamentals of General, Organic, and Biological …

Biochemistry

ISBN:

9780134015187

Author:

John E. McMurry, David S. Ballantine, Carl A. Hoeger, Virginia E. Peterson

Publisher:

PEARSON

SEE MORE TEXTBOOKS