HOMEWORK#4
Molecular viewer
- due on 4/22
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.
- Function: sublitisin is an extracellular alkaline serine protease. It does not resemble chymotrypsin except in the possession of a ser-his-asp catalytic triad. It catalyzes the hydrolysis of protein and peptide amides.
- Catalytic activity:Hydrolysis of proteins with broad specificty for peptide bonds, and a preference for a large uncharged residue in p1 .Hydrolyses peptide amides.The catalytic triad, however, is absolutely conserved. Ser221, His64 and Asp32 The same residues from chymotrypsin (Ser195, His57, Asp102)Unspecific serine endopeptidase used for the total hydrolysis of proteins and peptides at alkaline pH. Subtilisin cleaves ester and amide bond. It has been successfully used in the racemic resolution of amino acids, amines, carboxylic acids and alcohols. It shows activity in aqueous and organic solvents and it is well suited for peptide synthesis.
- Structure: Subtilisin is structurally quite different from chymotrypsin. It contains much more alpha-helical structure.Superposition of subtilisin and chymotrypsin shows their overall structures have little in common.
Scrip:
select helix
color blue
ribbons
select sheet
color red
strands
select turn
color yellow
ribbons
select 221
color cyan
Labels
sticks
select his64
color green
Labels
sticks
select asp32
color orange
sticks