The 1.6 A crystal structure of the catalytic domain of PlyB, a bacteriophage lysin active against Bacillus anthracis.
Lysins are peptidoglycan hydrolases that are produced by bacteriophage and act to lyse the bacterial host cell wall during progeny phage release. Here, we describe the structure and function of a novel bacteriophage-derived lysin, PlyB, which displays potent lytic activity against the Bacillus anthracis-like strain ATCC 4342. This molecule comprises an N-terminal catalytic domain (PlyB(cat)) and a C-terminal bacterial SH3-like domain, SH3b. It is shown that both domains are required for effective catalytic activity against ATCC 4342. Further, PlyB has specific activity comparable to the phage lysin PlyG, an amidase being developed as a therapeutic against anthrax. In contrast to PlyG, however, the 1.6 A X-ray crystal structure of PlyB(cat) reveals that the catalytic domain adopts the glycosyl hydrolase (GH)-25, rather than phage T7 lysozyme-like fold. PlyB therefore represents a new class of anthrax lysin and a new defensive tool in the armament against anthrax-mediated bioterrorism.
Porter
Corrine J
CJ
Protein Crystallography Unit, Department of Biochemistry and Molecular Biology and The ARC Centre of Excellence for Structural and Functional Microbial Genomics, Monash University, Clayton, Melbourne, VIC 3800, Australia.
Schuch
Raymond
R
Pelzek
Adam J
AJ
Buckle
Ashley M
AM
McGowan
Sheena
S
Wilce
Matthew C J
MC
Rossjohn
Jamie
J
Russell
Ryann
R
Nelson
Daniel
D
Fischetti
Vincent A
VA
Whisstock
James C
JC
D000595:Amino Acid Sequence; D001408:Bacillus anthracis / Q000737:chemistry / Q000821:virology*; D001435:Bacteriophages / Q000737:chemistry*; D001665:Binding Sites; D020134:Catalytic Domain; D018360:Crystallography, X-Ray; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009088:Mucoproteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D009699:N-Glycosyl Hydrolases / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D011485:Protein Binding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D017386:Sequence Homology, Amino Acid; D013329:Structure-Activity Relationship; D013379:Substrate Specificity; D014764:Viral Proteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification
D009088:Mucoproteins; D014764:Viral Proteins; C010393:lysin, gastropoda; D009699:N-Glycosyl Hydrolases; C518365:PlyB bacteriophage lysin