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2004 | 51 | 2 |

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Probing protein structure by limited proteolysis

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EN

Abstrakty

EN
Limited proteolysis experiments can be successfully used to probe conformational features of proteins. In a number of studies it has been demonstrated that the sites of limited proteolysis along the polypeptide chain of a protein are characterized by enhanced backbone flexibility, implying that proteolytic probes can pinpoint the sites of local unfolding in a protein chain. Limited proteolysis was used to analyze the partly folded (molten globule) states of several proteins, such as apomyoglobin, a-lactalbumin, calcium-binding lysozymes, cytochrome c and human growth hor­mone. These proteins were induced to acquire the molten globule state under spe­cific solvent conditions, such as low pH. In general, the protein conformational fea­tures deduced from limited proteolysis experiments nicely correlate with those deriv­ing from other biophysical and spectroscopic techniques. Limited proteolysis is also most useful for isolating protein fragments that can fold autonomously and thus be­have as protein domains. Moreover, the technique can be used to identify and pre­pare protein fragments that are able to associate into a native-like and often func­tional protein complex. Overall, our results underscore the utility of the limited pro- teolysis approach for unravelling molecular features of proteins and appear to prompt its systematic use as a simple first step in the elucidation of structure-dynamics- function relationships of a novel and rare protein, especially if available in minute amounts.

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Rocznik

Tom

51

Numer

2

Opis fizyczny

p.299-321,fig.,ref.

Twórcy

autor
  • University of Padua, Viale G.Colombo 3, 35121 Padua, Italy
autor
autor
autor
autor

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