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Monitoring the Reductive and Oxidative Half-Reactions of a Flavin-Dependent Monooxygenase using Stopped-Flow Spectrophotometry
Published on: March 18, 2012
Protection from nitrosative stress: a central role for microbial flavohemoglobin
Michael T Forrester1, Matthew W Foster
1Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA. mtforrester@partners.org
Free Radical Biology & Medicine
|February 21, 2012
Summary
Flavohemoglobin (flavoHb) detoxifies harmful nitric oxide (NO) in microbes and is explored for therapeutic NO depletion in plants and human tumors. This enzyme
Area of Science:
- Microbiology
- Biochemistry
- Molecular Biology
Background:
- Nitric oxide (NO) is a cytotoxic molecule produced during life in oxygen-rich environments.
- NO causes nitrosative stress and inhibits essential heme-containing proteins in aerobic respiration.
- Metabolizing NO is crucial for microbial survival.
Purpose of the Study:
- To review the molecular characteristics of flavohemoglobin (flavoHb).
- To explore NO-sensitive transcriptional machinery for flavoHb induction.
- To discuss flavoHb's role in resisting host defenses and its heterologous applications.
Main Methods:
- Literature review of flavoHb research.
- Analysis of genomic studies on NO protection mechanisms.
- Examination of flavoHb's heterologous applications in eukaryotes.
Main Results:
- FlavoHb converts NO and O(2) to nitrate (NO(3)(-)), protecting microbes from nitrosative stress.
- Transcriptional regulators like NsrR control inducible NO protection.
- FlavoHb has potential for in vivo NO depletion in therapeutic strategies.
Conclusions:
- FlavoHb is a key enzyme in microbial NO detoxification.
- Understanding flavoHb's regulation and function is vital for its therapeutic use.
- Further research is needed to address unresolved questions regarding flavoHb's applications.
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