The chito-oligosaccharide-specific lectin from pumpkin (Cucurbita maxima) phloem exudate has been purified to homogeneity by affinity chromatography on chitin. After SDS/PAGE in the presence of 2-mercaptoethanol, the pumpkin phloem lectin yielded a single band corresponding to a molecular mass of 23.7 kDa, whereas ESI-MS (electrospray ionization MS) gave the molecular masses of the subunit as 24645 Da. Analysis of the CD spectrum of the protein indicated that the secondary structure of the lectin consists of 9.7% α-helix, 35.8% β-sheet, 22.5% β-turn and 32.3% unordered structure. Saccharide binding did not significantly affect the secondary and tertiary structures of the protein. The haemagglutinating activity of pumpkin phloem lectin was mostly unaffected in the temperature range 4–70 °C, but a sharp decrease was seen between 75 and 85 °C. Differential scanning calorimetric and CD spectroscopic studies suggest that the lectin undergoes a co-operative thermal unfolding process centred at approx. 81.5 °C, indicating that it is a relatively stable protein.
Skip Nav Destination
Article navigation
Research Article|
April 21 2010
Rapid affinity-purification and physicochemical characterization of pumpkin (Cucurbita maxima) phloem exudate lectin
Akkaladevi Narahari;
Akkaladevi Narahari
1School of Chemistry, University of Hyderabad, Hyderabad 500046, India
Search for other works by this author on:
Musti J. Swamy
Musti J. Swamy
1
1School of Chemistry, University of Hyderabad, Hyderabad 500046, India
1To whom correspondence should be addressed (email mjssc@uohyd.ernet.in).
Search for other works by this author on:
Publisher: Portland Press Ltd
Received:
August 18 2009
Accepted:
September 07 2009
Accepted Manuscript online:
September 07 2009
Online ISSN: 1573-4935
Print ISSN: 0144-8463
© The Authors Journal compilation © 2010 Biochemical Society
2010
Biosci Rep (2010) 30 (5): 341–349.
Article history
Received:
August 18 2009
Accepted:
September 07 2009
Accepted Manuscript online:
September 07 2009
Citation
Akkaladevi Narahari, Musti J. Swamy; Rapid affinity-purification and physicochemical characterization of pumpkin (Cucurbita maxima) phloem exudate lectin. Biosci Rep 1 October 2010; 30 (5): 341–349. doi: https://doi.org/10.1042/BSR20090117
Download citation file:
Sign in
Don't already have an account? Register
Sign in to your personal account
You could not be signed in. Please check your email address / username and password and try again.
Captcha Validation Error. Please try again.