Oxidation of cysteine to cystine in Proinsulin

Stable Identifier
R-HSA-264997
Type
Reaction [transition]
Species
Homo sapiens
Compartment
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Cystine bonds are formed in Proinsulin-1 between cysteine residues 31 and 96, cysteine residues 43 and 109, and cysteine residues 95 and 100. Ero1-like alpha does not directly catalyze the oxidation of cysteines to cystine. Instead it maintains a suitably oxidizing environment for the reactions to occur . Though Ero1-like alpha can act via specific isomerases such as P4HB/PDI, there is currently no evidence that formation of cystine bonds in insulin requires a specific isomerase. Interestingly, even in beta cells of wild type animals, trace amounts of incorrectly bonded proinsulin can be detected. Thus, the formation of correct cystine bonds may involve a period of bond shuffling.

Literature References
PubMed ID Title Journal Year
9631292 The role of assembly in insulin's biosynthesis

Dodson, G, Steiner, D

Curr Opin Struct Biol 1998
12624089 In vitro refolding of human proinsulin. Kinetic intermediates, putative disulfide-forming pathway folding initiation site, and potential role of C-peptide in folding process

Qiao, ZS, Min, CY, Hua, QX, Weiss, MA, Feng, YM

J Biol Chem 2003
15096212 Unfolding of human proinsulin. Intermediates and possible role of its C-peptide in folding/unfolding

Min, CY, Qiao, ZS, Feng, YM

Eur J Biochem 2004
12590147 Role of the connecting peptide in insulin biosynthesis

Liu, M, Ramos-CastaƱeda, J, Arvan, P

J Biol Chem 2003
15705595 Proinsulin disulfide maturation and misfolding in the endoplasmic reticulum

Liu, M, Li, Y, Cavener, D, Arvan, P

J Biol Chem 2005
14744022 Role of disulfide bonds in the structure and activity of human insulin

Chang, SG, Choi, KD, Jang, SH, Shin, HC

Mol Cells 2003
Participants
Participant Of
Catalyst Activity
Catalyst Activity
Title
disulfide oxidoreductase activity of EROIL-like Proteins [endoplasmic reticulum lumen]
Physical Entity
Activity
Orthologous Events
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Reviewed
Created