Sample problem: Protein structure • A protein gives two bands of 50 and 80 kD on...
Sample problem: Protein structure • A protein gives two bands of 50 and 80 kD on SDS PAGE. Treatment with 2-mercaptoethanol gives two bands of 50kD and 40kD. Give detailed information about this protein including its molecular weight.
A protein gives two bands of 50 and 80 kD on SDS PAGE. Treatment with 2-mercaptoethanol gives two bands of 50kD and 40kD. Give detailed information about this protein including its molecular weight.
5. A protein has a molecular weight of 200 kD. On treatment with urea, two bands of 100kD and 50kD are obtained in SDS PAGE. After treatment with 2-mercaptoethanol, three bands of 40, 60 kD and 50KD are obtained. What information about the quaternary structure of the protein can be obtained? (5 marks)
Sample problem: Protein structure Determine the subunit composition of a protein from the following information: • Molecular mass by Gel filtration: 200kD • Molecular mass by SDS PAGE: 100kD • Molecular mass by SDS PAGE with 2- mercaptoethanol: 40 kD and 60 kD.
Carl has just finished purifying a protein and analysis by gel filtration indicated that the molecular weight of the native (undenatured) protein was 130,000 dalton. His advisor wanted him to determine whether this protein had quaternary structure using gel electrophoresis. He wants to be able to describe the molecular weight of each of the subunits and the forces involved in linking these subunits together (disulfide linkages and/or electrostatic, hydrogen bonding and hydrophobic interactions). Carl first analyzed his pure protein sample...
SDS Page Gel: The provided standard protein sample for electrophoresis consists of 9 polypeptides with molecular weights ranging from 250 to 15 KDa. Sample 1: Protein A in a sample buffer with B-Mercaptoethanol Sample 2: Protein A in a sample buffer without B-Mercaptoethanol Sample 3: Protein B in a sample buffer with B-Mercaptoethanol Sample 4: Protein C in a sample buffer without B-Mercaptoethanol Use the picture below & the information about the proteins above to answer the following questions. 1a....
A protein sample complex consists of two proteins, a smaller protein, X, and a larger protein, Y. Protein X is composed of two polypeptide chains linked by disulfide bonds. Protein Y is composed of three polypeptide chains linked by disulfide bonds. The complex is analyzed by native PAGE, reducing SDS-PAGE and non-reducing SDS-PAGE. Native PAGE does not include sodium dodecyl sulfate, or SDS. Reducing SDS-PAGE uses both SDS and a reducing agent in the buffer. Non-reducing SDS-PAGE uses SDS, but...
A protein is purified from a bacterium using Size Exclusion Chromatography (SEC), with a molecular weight of 200kD. When this protein is run on SDS-PAGE , a sing band is observed at 100kD. Based on these observations, what can be concluded about the structure of the protein? The protein consist of two 200kD subiunits The protein has a quaternary structure The protein is madeup of two 100 kD subunits Proteins is a tetramer consisting of 200 kD domains. The protein...
Two different experiments were performed to determine the quaternary structure of HCV reverse transcriptase as well as the molecular size of each subunit. In these experiments, HCV reverse transcriptase was mixed with equal masses of two proteins with known molecular weights of 10 KDa and 80 KDa. Both of these proteins consisted of a single polypeptide chain. This mixture was then separated by gel filtration (below) or by SDS-PAGE (below). Gel Filtration Column: The absorption as a function of the...
Data Analysis Problem by Marianna Pap and József Szeberényi to accompany The Cell: A Molecular Approach, Seventh Edition Geoffrey M. Cooper and Robert E. Hausman 2.3 The Effect of a Reducing Agent on Protein Structure Source: Janatova, J. 1986. Detection of disulphide bonds and localization of interchain linkages in the third (C3) and the fourth (C4) components of human complement. Biochem, J. 233: 819-825. Level of difficulty: Medium Corresponding chapter(s) in the textbook: Chapter 2 Review the following terms before...