Title
Isolation and initial structural characterization of a 27 kDa protein from Zingiber officinale
Author
Saima Rasheed, Shoaib Ahmad Malik, Sven Falke, Ali Arslan, Ramin Fazel, Hartmut Schlüter, Christian Betzel, M. Iqbal Choudhary
Year
2018
Journal
Journal of Molecular Structure
Abstract
Zingiber officinale Roscoe (Ginger) is a widely used traditional medicinal plant (for different ailments such as arthritis, constipation, and hypertension). This article describes the isolation and characterization of a so far unknown protein from ginger rhizomes applying ion exchange, affinity, size-exclusion chromatography, small angle X-ray scattering (SAXS), and mass spectrometry techniques. One-dimensional Coomassie-stained SDS-PAGE was performed under non-reducing conditions, showing one band corresponding to approx. 27 kDa. Dynamic light scattering (DLS) analysis of the protein solution revealed monodispersity and a monomeric state of the purified protein. Circular dichroism (CD) spectroscopy strongly indicated a β-sheet-rich protein, and disordered regions. MALDI-TOF-MS, and LC-MS/MS analysis resulted in the identification of 27.29 kDa protein, having 32.13% and 25.34% sequence coverage with Zingipain-1 and 2, respectively. The monomeric state and molecular weight were verified by small angle X-ray scattering (SAXS) studies. An elongated ab-initio model was calculated based on the scattering intensity distribution.
Instrument
J-815
Keywords
Circular dichroism, Secondary structure, Natural products, Biochemistry