HOMEWORK 4

The Question:

Find an interesting protein, say, subtilisin, and give a brief description of the structure and function of this protein. And then use Rasmol to show the structural features of this protein. You should put in your homepage your Rasmol scripts as plain text and some of the represenative images generated by the script.

The Answer:

   Something about TNF

    TNF(tumor necrosis factor) is a multiffunction cytokine protein. It mainly secreted by mitogen-active macrophage. TNF can elicated a large number of biological effect including   hemorrhagic necrosis of transplanting tumors, cytotoxicity, antiviral response, growth and differentiation of cells, response of inflammation, regulation of immunse response (It  inclued that cytoxicity toward ceratin cellsand tumors). The structure  of TNF in Protein DataBase is crystal structure of human CD40 ligand. The TNF has 146 residues. The secondary structure of TNF has helix structure and sheet and it is composed of homotrimer.

Please press this, you will see the structure of TNF

The Rasmol script

wireframe off

select all

cartoons

color white

select  helix

cartoons

color yellow

select sheet

cartoons

color purple

rotate x 20 (repeat this order until the structure rotate 180 degree)

zoom 120, 140, 160, 180, 200

rotate x 20 (repeat this order intil the structure rotate 180 degree)