Actomyosin modulation by peroxynitrite
In the present work we address the oxidative modifications accounting for the structural and functional impairment of the actomyosin complex under the oxidative stress mediated by peroxynitrite (ONOO-). Experiments on purified myosin and actin have shown that submicromolar ONOO- concentrations produ...
| Main Author: | |
|---|---|
| Other Authors: | , , , |
| Format: | conferenceObject |
| Language: | eng |
| Published: |
2012
|
| Subjects: | |
| Online Access: | http://hdl.handle.net/10400.1/1310 |
| Country: | Portugal |
| Oai: | oai:sapientia.ualg.pt:10400.1/1310 |
| Summary: | In the present work we address the oxidative modifications accounting for the structural and functional impairment of the actomyosin complex under the oxidative stress mediated by peroxynitrite (ONOO-). Experiments on purified myosin and actin have shown that submicromolar ONOO- concentrations produce strong inhibition of the F-actin stimulated myosin ATPase activity. The peroxynitrite-induced actomyosin impairment correlated with structural modifications that decrease the thermal stability of both actin and myosin leading to partially unfolded states. The results suggest a major role for the highly reactive cysteines on actin and on myosin and also for some critical methionines on G-actin. 3-nitrotyrosine does not contribute significantly to the observed functional alterations. |
|---|