[Frontiers in Bioscience 7, a9-14, February 1, 2002]

PROTEIN DENITRATION/MODIFICATION BY ESCHERICHIA COLI NITRATE REDUCTASE AND MAMMALIAN CYTOCHROME P-450 REDUCTASE

Wu-Nan Kuo, Joseph M. Kocis and Jenny Webb (Kreahling)

Division of Science and Mathematics, Bethune-Cookman College, Daytona Beach,Florida 32114

TABLE OF CONTENTS

1. Abstract
2. Introduction
3. Materials and Methods
3.1. Materials
3.2. Preparation of peroxynitrite (PN)-treated histone III-S (NH) and subsequent NADPH or GSH-treated NH
(NHNADPH or NHGSH)
3.3. Enzymatic modification of NH, NHNADPH and NHGSH
3.4. Enzymatic denitration of NH, NHNADPH and NHGSH
4. Results and Discussion
5. Acknowledgement
6. References

1. ABSTRACT

The incubation of peroxynitrite (PN)-pretreated histone III-S (NH) with Escherichia coli nitrate reductase (cytochrome, NADPH/GSH-independent) and that of NADPH-treated NH (NHNADPH) with liver cytochrome P-450 reductase (NADPH-dependent) resulted in decreased 3-nitrotyrosine immunoreactivity found in Western blot analysis. Additionally, increased nitrate was noted as an end product of these reactions. These findings imply that varied enzymatic denitration/modification of NO/PN-reacted protein, either with or without a reductant, may be important in regulating related signal transduction cascade(s) and relieving oxidative stress.