Oxidative Modification of Proteins: An Emerging Mechanism of Cell Signaling

Abstract

There are a wide variety of reactive species which can affect cell function, including reactive oxygen, nitrogen, and lipid species. Some are formed endogenously through enzymatic or non-enzymatic pathways, and others are introduced through diet or environmental exposure. Many of these reactive species can interact with biomolecules and can result in oxidative post-translational modification of proteins. It is well documented that some oxidative modifications cause macromolecular damage and cell death. However, a growing body of evidence suggests that certain classes of reactive species initiate cell signaling by reacting with specific side chains of peptide residues without causing cell death. This process is generally termed “redox signaling,” and its role in physiological and pathological processes is a subject of active investigation. This review will give an overview of oxidative protein modification as a mechanism of redox signaling, including types of reactive species and how they modify proteins, examples of modified proteins, and a discussion about the current concepts in this area.

Diverting Glycolysis to Combat Oxidative Stress

“…Thus, the thiolate anion is sensitized to changes in cellular ROS and ready to respond. In addition, thiols can react with electrophilic species via a Michael addition mechanism to form a covalent adduct potentially triggering the thiol switch [ 9 ].…”

Oxidative Stress: Noxious but Also Vital

“…This last may be oxidized again producing a sulfinic acid (R-SO 2 H). With high levels of stress oxidative, cysteines can further be oxidized to a sulfonic acid (R-SO 3 H) [70,76]. While sulfenic and sulfinic acids can be enzymatically reversible by the glutathione and thioredoxin enzyme systems [77] (Details about antioxidant mechanisms in next section), the sulfonic acid in cysteine residues seems to represent an irreversible protein damage.…”

“…The protein adducts have been observed in several pathologic conditions [67,68], suggesting their deleterious effects. However, whether these endogenous modifications are produced in a controlled manner, they may also control physiological responses [69,70].…”

“…The protein adducts have been observed in several pathologic conditions [67,68], suggesting their deleterious effects. However, whether these endogenous modifications are produced in a controlled manner, they may also control physiological responses [69,70].It is important to stress that the presence of proteins containing nitrotyrosine residues, for example, has been a biomarker of damage by reactive species [67,68]. The tyrosine nitration occurs by addition of NO 2 to the ortho position of the phenolic ring of this amino acid.…”

Оцінка Окисного Стресу І Рівень Молекулярних Ушкоджень При Позалікарняній Пневмонії В Дітей Із Йододефiцитного Регіону

“…Еще одним из маркеров окислительного стресса служат процессы окислительной модификации белков сыворотки крови, что отражено в научной литературе [27]. Анализ спонтанной ОМБ у обследованных детей выявил существенные различия интенсивности окислительного стресса среди пациентов І и ІІ групп (табл.…”