Interaction of Sodium Dodecyl Sulfate with Multi-subunit Proteins: A case study with CARMIN
IR@CSIR-CFTRI
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Relation |
http://ir.cftri.com/1618/
JBC-07-93 |
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Title |
Interaction of Sodium Dodecyl Sulfate with Multi-subunit Proteins: A case study with CARMIN
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Creator |
Sudhindra Rao, K.
Prakash, V. |
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Subject |
03 Proteins
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Description |
Sodium dodecyl sulfate (SDS) dissociates the multi- meric protein, carmin, into its monomers (2 S ) at low concentration. Dissociation begins at and above 1.6 mM SDS concentration and reaches 50% at 5 mM SDS concentration. Denaturation occurs above 5 mM SDS concentration. The dissociation step involves binding of 640 f 50 mol of SDS/mol of protein with an associ- ation constant, K, of 6.90 f 0.35 X 10’ M-‘. The inter- action reflects a AG“ = -4.0 f 0.1 kcal mol”. In the denaturation step, the K, has the same value, and the y value is nearly 2-fold higher. Dissociation of carmin thus begins only above a binding of 0.60 g of SDS/g of protein. Analysis of the binding data at 37 “C indicates a maximum of 1030 f 90 mol of SDS bound/mol of protein, which is equivalent to 1.14 f 0.10 g of SDS/g of protein. Upon denaturation, the a-helix content of the protein increases from 4 to 15%. Kinetically, the denaturation process consists of a two-step process (a fast and a slow step). The first order rate constants for these steps are 89.6 2 8.1 and 16.8 f 1.5 min-’, re- spectively, at 6.3 mM SDS concentration. The proc- esses of dissociation and denaturation occur sequen- tially. Dissociation of the protein is reversible, whereas the process of denaturation is only partially reversible as reflected by sedimentation velocity and conforma- tional analysis. These data are taken as a model for general understanding of the dissociation and/or de- naturation processes, which could be either sequential or simultaneous in multimeric proteins. |
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Date |
1993-07
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Type |
Article
PeerReviewed |
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Format |
application/pdf
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Language |
en
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Rights |
—
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Identifier |
http://ir.cftri.com/1618/1/J._Biol._Chem.%2C_Jul_1993_268_14769_-_14775.pdf
Sudhindra Rao, K. and Prakash, V. (1993) Interaction of Sodium Dodecyl Sulfate with Multi-subunit Proteins: A case study with CARMIN. Journal of Biological Chemistry, 268 (20). pp. 14769-14775. |
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