seedstorageprotein.pptx

seed storage proteins and their importance

1. Bhagyashree Shelar MT321 Dr. D.Y. Patil Biotechnology and Bioinformatics Institute , Pune. Seed Storage Protein.

2. What is seed storage protein? Roles - Classification- Summary- Content

3. * The plant seed is not only the organ of propagation and dispersion but also harvested by humans. * The amount of protein present in the seed varies from ~10%(in cereals) to ~40 % (in legumes and oilseeds ) . What is seed storage protein ?????

4. * Are generated mainly during seed production and stored in the seed . * It serves as nitrogen sources for the developing embryo during seed germination.

5. Majority of protein in seed perform either metabolic or structural roles. Storage of Amino acids for use during seed germination and seedling growth. Nutritional value of seed. Plays role in defense mechanisms. Source of Sulphur and Nitrogen. Roles of Seed Storage Protein :

6. Synthesis at high level in specific tissues and at certain stage of development. In mature seed found in discrete deposits called protein bodies.

7. Classified on the basis of solubility by T.B. Osborne:- Soluble in Dilute saline solution......Globulins Soluble in Alcohols............................Prolamins Soluble in Dilute Acids......................Glutelins Soluble in water.................................Albumins Classification of Seed Storage Proteins:

8. Globulin

9. The embryo and outer aleuronic layer of the endosperm contain globulin storage protein. They are present in dicot, monocots(including cereals and palms) and fern spores . They can be divided into two groups based on their sedimentation coefficients : 7S Viclilin-type globulins 11S Legumin-type globulins Globulin :-

10. Both groups show considerable variation in their structures resulting partly from post-translational processing. Globulin are defecient in cyctein and metheonine but 11S globulin are rich in these both amino acids. Cont....

11. The rice protein are no readily soluble in dilute salt solution and hence classically define as glutelins ;but they clearly belong to the 11S to 12S globulin family. Legumin and Viclilin are present in Pisum sativum and that similar protein can be isolated from other leguminous plant like Phaseolus Vulgaris(Flat bean). Cont.......

12. Prolamins

13. Major endosperm storage protein (~50% )of all cereal grains except rice and oats (~5% to 10% ). Prolamins are restricted to the family of grasses. Prolamins usually account for approximately half of the total grain nitrogen. Prolamins are recognized on the basis of their solubility in alcohol and their high levels of glutamine and proline . Prolamins

14. In prolamins, amino acid sequences are present consisting of repeated unit of Metheonine ,Glycine ,Histamine. E.g.: Zein in maize Protect seed against microbial attack. The α- Zeins of Maize account for ~75 to 80% of the total prolamins in maize. They have structures consisting of repeated sequences of unique N- and C-terminal domains Cont.............

15. Glutelins

16. They are generally prolamins like protein in certain grass(monocot) seed. Glutelins are the seed storage protein in mature wheat seeds (closely related species). It is the sticky substance in wheat which allows dough to rise and retain its shape during baking.  Glutelins are the primary energy storage in the endosperm of rice. Glutelins

17. There are typically high-molecular-weight (HMW) and low-molecular-weight (LMW) glutelins in different species. They crosslink with themselves and other proteins during baking via disulfide bonds. Cont..........

18. Albumin

19. Sedimentation coefficient of Albumin is 2S. They are widely distributed in dicot seeds and have been most widely studied in the Brassicaceae, notably oil- seed rape and Arabidopsis. 2S albumins are compact globular proteins with conserved cysteine residues. Albumin

20. 2S albumins can also play a protective role in plants as defensive weapons against fungal attack . The amino acid composition of 2S albumin proteins from many plant species has revealed their high content of sulphur-containing amino acids . Cont.....

21. Seed is the organ of propagation ,protein content of seed is 40%(leguminous and oil seed) to 10%(cereals). Perform metabolic , structural, defensive role. Provide nitrogen , sulphur, carbon to seed. Classified on the basis of solubility into four types albumin, globulin, prolamins, glutelins etc. Globulins present in both dicot ,monocot and fern spores. And of two types 7Sand 11S globulin. Summary

22. Prolamins are major Nitrogen source of seed and present in monocots only . Zein protein maize protects seed from microbial attack Glutelins are globulin (11S to 12S) which are not soluble in dilute saline solution. Present in the monocot seeds. Albumins are important source of sulphur and protects seed form fungal attack. Cont...

23. www.ncib.nlm.nih www.reserchgate.com Jxb.oxfordjournel.in Source:-

24. Thank You!