Balsamin, a novel ribosome-inactivating protein from the seeds of Balsam apple Momordica balsamina

作者：Kaur Inderdeep; Yadav Santosh K; Hariprasad Gururao; Gupta R C; Srinivasan Alagiri; Batra Janendra K; Puri Munish^*

来源：Amino Acids, 2012, 43(2): 973-981.

DOI：10.1007/s00726-011-1162-1

• Ribosome inactivating protein (RIP)
• Momordica balsamina
• RNA N-glycosidase
• Balsamin
• Cucurbitaceae

Plant seeds, a rich source of proteins, are considered important for their application as functional ingredients in a food system. A novel ribosome-inactivating protein (RIP), balsamin was purified from the seeds of Balsam apple, Momordica balsamina. Balsamin was purified by ion exchange chromatography on CM Sepharose and gel filtration on superdex-75. It has a molecular weight of 28 kDa as shown by SDS-PAGE analysis. Balsamin inhibits protein synthesis in a rabbit reticulocyte lysate-based cell free translation assay with an IC50 of 90.6 ng ml(-1). It has RNA N-glycosidase activity and releases a 400-base long fragment termed the Endo fragment from 28S rRNA in the same manner as does saporin-6 from Saponaria officinalis. The N-terminal sequence analysis of the first 12 amino acids of balsamin revealed that it shares 83% similarity with type I RIP alpha-MMC from Momordica charantia and 50% similarity with beta-MMC (from Momordica charantia), bryodin I (from Bryonia dioica) and luffin a (from Luffa cylindrica). Balsamin was further characterized by mass spectrometry. CD spectroscopic studies indicate that secondary structure of balsamin contains helix (23.5%), beta-strand (24.6%), turn (20%) and random coil (31.9%). Thus RIPs activity expressed in vegetables like Momordica sp. advocates its usage in diet.

• 出版日期2012-8
• 单位迪肯大学; 河北医科大学