Sandbox7 Eric Martz
From Proteopedia
Proposed Title: Nitrotyrosine.
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This page is reserved for a collaboration between User:Eric Martz and Hermes J Garbán. |
Nitrotyrosine results from the post-translational modification of the standard amino acid tyrosine. Reactive nitrogen compounds produced in inflammation are typically responsible. Nitrosylation of tyrosine tends to inactivate enzymes. In March, 2011, there are 13 entries in the PDB containing coordinates for 3-nitrotyrosine (meta-nitro-tyrosine), with the [ID] NIY. These include six sequence-distinct proteins, represented by ribonucleotide reductase 2xof and 2xap, laccase 3div, Human Manganese Superoxide Dismutase 2adp, Human Glutathione Reductase 1k4q, and bovine Cu,Zn superoxide dismutase 1sda. Not surprisingly, the NO2 adduct, being very hydrophilic, is often on the surface of the protein.
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One of the more interesting cases may be Human Manganese Superoxide Dismutase, for which structures are available for the wild type 2adq, shown at right (), and the nitrated form, 2adp. In this structure, Mn++ is . The is by four histidine nitrogens, one aspartate oxygen, and one water. Tyrosine 34 is nearby (5.2 Ångstroms), but not near enough to be interacting with the Mn++ or its cage. extends it towards the Mn++. The partially negatively charged oxygens in the NO2 are 3.6-3.8 Å from the electron-hungry Mn++. slightly farther from the Mn++, but causes no other significant conformational changes[1].
See Also
- Nitrotyrosine in Wikipedia.
Notes
- ↑ DeepView was used to align all atoms of the three Mn-coordinating histidines. In the resulting file Image:2adq-2adp-3hisaln.pdb, 2adq is model 1, and 2adp is model 2.
