2ar3

[[Image:2ar3.gif|left|200px]]<br /><applet load="2ar3" size="350" color="white" frame="true" align="right" spinBox="true"

caption="2ar3, resolution 2.20&Aring;" />

'''E90A mutant structure of PlyL'''<br />

==Overview==

We report a structural and functional analysis of the lambda prophage Ba02 endolysin (PlyL) encoded by the Bacillus anthracis genome. We show that PlyL comprises two autonomously folded domains, an N-terminal catalytic domain and a C-terminal cell wall-binding domain. We determined the crystal structure of the catalytic domain; its three-dimensional fold is related to that of the cell wall amidase, T7 lysozyme, and contains a conserved zinc coordination site and other components of the catalytic machinery. We demonstrate that PlyL is an N-acetylmuramoyl-L-alanine amidase that cleaves the cell wall of several Bacillus species when applied exogenously. We show, unexpectedly, that the catalytic domain of PlyL cleaves more efficiently than the full-length protein, except in the case of Bacillus cereus, and using GFP-tagged cell wall-binding domain, we detected strong binding of the cell wall-binding domain to B. cereus but not to other species tested. We further show that a related endolysin (Ply21) from the B. cereus phage, TP21, shows a similar pattern of behavior. To explain these data, and the species specificity of PlyL, we propose that the C-terminal domain inhibits the activity of the catalytic domain through intramolecular interactions that are relieved upon binding of the C-terminal domain to the cell wall. Furthermore, our data show that (when applied exogenously) targeting of the enzyme to the cell wall is not a prerequisite of its lytic activity, which is inherently high. These results may have broad implications for the design of endolysins as therapeutic agents.

 

==About this Structure==

2AR3 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_anthracis Bacillus anthracis] with <scene name='pdbligand=ZN:'>ZN</scene> and <scene name='pdbligand=PO4:'>PO4</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/N-acetylmuramoyl-L-alanine_amidase N-acetylmuramoyl-L-alanine amidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.5.1.28 3.5.1.28] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2AR3 OCA].

 

==Reference==

Structure and lytic activity of a Bacillus anthracis prophage endolysin., Low LY, Yang C, Perego M, Osterman A, Liddington RC, J Biol Chem. 2005 Oct 21;280(42):35433-9. Epub 2005 Aug 15. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=16103125 16103125]

[[Category: N-acetylmuramoyl-L-alanine amidase]]

[[Category: Single protein]]

[[Category: Liddington, R C.]]

[[Category: Low, L Y.]]

[[Category: Osterman, A.]]

[[Category: Perego, M.]]

[[Category: Yang, C.]]