Ajith K. AravindakshanUniversity of Hyderabad Department of Biochemistry School of Life Sciences Hyderabad 500 046 India |
||
| Email: | ajitharavind2008@yahoo.com | |
"Comparative study on structural characterization of Lysosomal enzymes in the invertebrates"
Lysosomes contain more than 50 hydrolytic enzymes that help the cell to digest the macromolecules present inside. Like all other proteins these enzymes are also synthesized with in the rough endoplasmic recticulum and transported into the lysosome. There are special receptors that are required for the transport of lysosomal enzymes from the trance golgi network to the endosomes. The enzymes are tagged with a mannose-6-phosphate residue within the golgi network and this mannose 6-phosphate residues are identified by the receptors inside the cell and are transported them to the endosomes. These receptors are called mannose 6-phosphate receptor proteins or MPR proteins. There are two different MPR proteins reported namely MPR 300 and MPR 46. Our lab has been working with the structural and functional similarities that exist within the MPR proteins of non mammalian vertebrates and invertebrates to the mammalian proteins, so as to confirm the common evolutionary origin of the lysosomal biogenesis. Apart from this, lysosomal enzymes like α- fucosidase has been purified from the starfish and Unio. The lysosomal enzymes which are well characterized within the higher mammals include β-glucuronidase, α- fucosidase, α- galactosidase and cathepsin D.
It is important to understand the properties of these enzymes from invertebrates so as to compare with representative enzymes from the higher mammals. So, my objective is to purify the enzymes mentioned above from the higher invertebrates like star fish, biochemically characterize them and obtain the aminoacid sequence and understand their structural relatedness to the vertebrate enzymes. The aim also includes the isolation of the glycopeptides from the purified enzymes, determination of the glycan sequences of the enzymes and assigning the specific linkage sites of the glycans to the protein sequences to make a comparative study of the structures determined to those known in literature.
