Structural Study of the C2 Domains of the Classical PKC Isoenzymes Using Infrared Spectroscopy and Two-Dimensional Infrared Correlation Spectroscopy
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- 作者：Alejandro Torrecillas ; Senena Corbalá ; n-Garcí ; a ; and Juan C. Gó ; mez-Ferná ; ndez
- 刊名：Biochemistry
- 出版年：2003
- 出版时间：October 14, 2003
- 年：2003
- 卷：42
- 期：40
- 页码：11669 - 11681
- 全文大小：464K
- 年卷期：v.42,no.40(October 14, 2003)
- ISSN：1520-4995
文摘
The secondary structure of the C2 domains of the classical PKC isoenzymes, 
, 
, and 
,has been studied using infrared spectroscopy. Ca2+ and phospholipids were used as protein ligands tostudy their differential effects on the isoenzymes and their influence on thermal protein denaturation.Whereas the structures of the three isoenzymes were similar in the absence of Ca2+ and phospholipids at25 
C, some differences were found upon heating in their presence, the C2 domain of the -isoenzymebeing better preserved from thermal denaturation than the domain from the -isoenzyme and this, in turn,being better than that from the -isoenzyme. A two-dimensional correlation study of the denaturation ofthe three domains also showed differences between them. Synchronous 2D-IR correlation showed changes(increased aggregation of denaturated protein) occurring at 1616-19 cm-1, and this was found in thethree isoenzymes. On the other hand, the asynchronous 2D-IR correlation study of the domains in theabsence of Ca2+ showed that, in all cases, the aggregation of denaturated protein increased after changesin other structural components, an increase perhaps related with the hard-core role of the -sandwich inthese proteins. The differences observed between the three C2 domains may be related with theirphysiological specialization and occurrence in different cell compartments and in different cells.
, , and ,has been studied using infrared spectroscopy. Ca2+ and phospholipids were used as protein ligands tostudy their differential effects on the isoenzymes and their influence on thermal protein denaturation.Whereas the structures of the three isoenzymes were similar in the absence of Ca2+ and phospholipids at25 C, some differences were found upon heating in their presence, the C2 domain of the -isoenzymebeing better preserved from thermal denaturation than the domain from the -isoenzyme and this, in turn,being better than that from the -isoenzyme. A two-dimensional correlation study of the denaturation ofthe three domains also showed differences between them. Synchronous 2D-IR correlation showed changes(increased aggregation of denaturated protein) occurring at 1616-19 cm-1, and this was found in thethree isoenzymes. On the other hand, the asynchronous 2D-IR correlation study of the domains in theabsence of Ca2+ showed that, in all cases, the aggregation of denaturated protein increased after changesin other structural components, an increase perhaps related with the hard-core role of the -sandwich inthese proteins. The differences observed between the three C2 domains may be related with theirphysiological specialization and occurrence in different cell compartments and in different cells.