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Mass spectrometry of oxidized peptides from peroxisomal malate synthase and catalase
Author(s) -
Anand Pria,
Donaldson Robert P,
Simha Rahul
Publication year - 2008
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.22.1_supplement.623.1
Subject(s) - peroxisome , malate synthase , chemistry , catalase , biochemistry , mass spectrometry , peroxisomal targeting signal , glyoxylate cycle , enzyme , chromatography , isocitrate lyase , gene
Oxidative damage is irreparable and marks proteins for degradation. If oxidized proteins are not degraded, they can form aggregates linked to age‐related disorders. In peroxisomes such damage is likely due to the generation of reactive oxygen species. Our purpose was to observe the effects of oxidation on peroxisomal proteins. Peroxisomal proteins were subjected to H 2 O 2 in vivo, then analyzed for oxidation using Western blotting with a biotin/avidin detection system. Mass spectrometry was used along with a novel JAVA program to identify oxidized peptides within catalase (CAT) and malate synthase (MS). H 2 O 2 exposure was found to increase the activity of CAT, and to increase the number of oxidized peptides found in both CAT and MS. When an oxidized protein was tagged with biotin hydrazide, several peptides were observed less frequently in the mass spectra than in the non‐oxidized sample. Biotin tagged peptides shift to different masses. CAT had 13 peptides that were affected by oxidation and MS had 10. These peptides have definable locations within the proteins. This type of analysis could lead to an understanding of how sites of oxidation relate to functional alterations, degradation or aggregation. NSF REU #0649165