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Updated: Jul 16, 2026
11:28
Analytical Techniques for Assaying Nitric Oxide Bioactivity
Published on: June 18, 2012
Nitric oxide synthases: domain structure and alignment in enzyme function and control
1Department of Medicine, Duke University and VA Medical Center, Durham, NC 27705, USA. dgx@acpub.duke.edu
Frontiers in Bioscience : a Journal and Virtual Library
|November 29, 2002
Summary
Nitric Oxide Synthases (NOS) are crucial enzymes involved in cell signaling and immune defense. This review focuses on their structure, catalysis, and control mechanisms, highlighting domain interactions and isoform specificity.
Area of Science:
- Biochemistry
- Molecular Biology
- Enzymology
Background:
- Nitric Oxide Synthases (NOS) produce nitric oxide (NO) from arginine, oxygen, and NADPH.
- NOS enzymes are critical for cell signaling and immune responses.
- Eukaryotic NOS evolved through gene fusions, developing sophisticated, isoform-specific control mechanisms.
Purpose of the Study:
- To review recent structural information on NOS isoforms.
- To deepen the understanding of NOS structure-function relationships.
- To focus on domain alignment in catalysis and control.
Main Methods:
- Analysis of primary amino acid sequences.
- High-resolution crystallography of NOS isoforms.
- Examination of interdomain interactions and dimerization.
Main Results:
- Structural data reveals insights into cofactor, substrate, and inhibitor binding.
- Understanding of NOS catalysis and control mechanisms is advancing.
- Alignment of molecular surfaces of folded domains is key to enzyme function.
Conclusions:
- Detailed structural information enhances understanding of NOS function.
- Further research is needed to fully elucidate NOS reaction mechanisms and control.
- Domain alignment is central to NOS structure, catalysis, and regulation.
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