InterPro domain: IPR036312

This entry represents a superfamily of structural domains consisting of 4-helices with a folded leaf topology, and forming a right-handed superhelix. This domain occurs in several proteins, including:

• Plant lipid-transfer proteins, such as the non-specific lipid-transfer proteins ns-LTP1 and ns-LTP2 [ 1 , 2 ].
• Proteinase/alpha-amylase inhibitors, such as trypsin/alpha-amylase inhibitor RBI from Eleusine coracana (Indian finger millet) [ 3 ] and Hageman factor/amylase inhibitor from Zea mays (Maize) [ 4 ].
• Seed storage proteins, such as napin from Brassica napus (Rape) [ 5 ] and 2S albumin from Ricinus communis (Castor bean) [ 6 ].

1. The crystal structure of a wheat nonspecific lipid transfer protein (ns-LTP1) complexed with two molecules of phospholipid at 2.1 A resolution. Eur. J. Biochem. 264, 562-8
2. Solution structure of plant nonspecific lipid transfer protein-2 from rice (Oryza sativa). J. Biol. Chem. 277, 35267-73
3. A novel strategy for inhibition of alpha-amylases: yellow meal worm alpha-amylase in complex with the Ragi bifunctional inhibitor at 2.5 A resolution. Structure 6, 911-21
4. Structural determinants of the bifunctional corn Hageman factor inhibitor: x-ray crystal structure at 1.95 A resolution. Biochemistry 37, 15277-88
5. 1H NMR assignment and global fold of napin BnIb, a representative 2S albumin seed protein. Biochemistry 35, 15672-82
6. Solution structure of RicC3, a 2S albumin storage protein from Ricinus communis. Biochemistry 42, 13839-47