3-Methylornithine

3-Methylornithine is an amino acid with the formula H₂N(CH₂)₂CH(CH₃)CH(NH₂)CO₂H. This amino acid contains two stereogenic centers, but only one stereoisomer (namely (3R)-3-methyl-D-ornithine) occurs in nature. It is produced from lysine by the action of the enzyme methylornithine synthase. The combination of lysine and 3-methylornithine, also mediated enzymatically, produces pyrrolysine, which, for a few organisms, is a "22nd" genetically coded amino acid.[1][2]

Structure of pyrrolysine, which is biosynthesized from methylornithine and lysine

3-Methylornithine

Names
Other names 5-Aminoisoleucine
Identifiers
CAS Number	1224728-50-0
3D model (JSmol)	Interactive image
ChemSpider	26001508
KEGG	C20277
PubChem CID	87372817
InChI InChI=1S/C6H14N2O2/c1-4(2-3-7)5(8)6(9)10/h4-5H,2-3,7-8H2,1H3,(H,9,10)/t4-,5-/m1/s1 Key: HYUPFEBCCJWDJX-RFZPGFLSSA-N InChI=1/C6H14N2O2/c1-4(2-3-7)5(8)6(9)10/h4-5H,2-3,7-8H2,1H3,(H,9,10)/t4-,5-/m1/s1 Key: HYUPFEBCCJWDJX-RFZPGFLSBQ
SMILES C[C@H](CCN)[C@H](C(=O)O)N
Properties
Chemical formula	C6H14N2O2
Molar mass	146.190 g·mol^−1
Appearance	White solid
Density	1.121 g/cm^3
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

References

1. Gaston, Marsha A.; Jiang, Ruisheng; Krzycki, Joseph A. "Functional Context, Biosynthesis, and Genetic Encoding of Pyrrolysine" Current Opinion in Microbiology 2011, vol. 14, pp. 342-349. doi:10.1016/j.mib.2011.04.001
2. Quitterer, F.; Beck, P.; Bacher, A.; Groll, M., "Structure and Reaction Mechanism of Pyrrolysine Synthase (PylD)", Angew. Chem. Int. Ed. 2013, volume 52, pp. 7033-7037. doi:10.1002/anie.201301164