PDBsum entry 3csr

Hydrolase

PDB id: 3csr

Contents

Protein chain

159 a.a. *

Waters ×105

* Residue conservation analysis

PDB id:

3csr

Name:

Hydrolase

Title:

Crystal and cryoem structural studies of a cell wall degrading enzyme in the bacteriophage phi29 tail

Structure:

Morphogenesis protein 1. Chain: a. Synonym: late protein gp13. Engineered: yes

Source:

Bacteriophage phi-29. Gene: 13. Expressed in: escherichia coli.

Resolution:

1.80Å R-factor: 0.195 R-free: 0.237

Authors:

Y.Xiang,M.G.Rossmann

Key ref:

Y.Xiang et al. (2008). Crystal and cryoEM structural studies of a cell wall degrading enzyme in the bacteriophage phi29 tail. Proc Natl Acad Sci U S A, 105, 9552-9557. PubMed id: 18606992

Date:

10-Apr-08 Release date: 01-Jul-08

Protein chain

P15132  (GP13_BPPH2) -  Morphogenesis protein 1 from Bacillus phage phi29

Seq: 365 a.a.

Struc: 159 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

Enzyme reactions

• Enzyme class 1: E.C.3.2.1.- - ?????
• Enzyme class 2: E.C.3.4.-.-

Note, where more than one E.C. class is given (as above), each may correspond to a different protein domain or, in the case of polyprotein precursors, to a different mature protein.

Proc Natl Acad Sci U S A 105:9552-9557 (2008)

PubMed id: 18606992

Crystal and cryoEM structural studies of a cell wall degrading enzyme in the bacteriophage phi29 tail.

Y.Xiang, M.C.Morais, D.N.Cohen, V.D.Bowman, D.L.Anderson, M.G.Rossmann.

ABSTRACT

The small bacteriophage phi29 must penetrate the approximately 250-A thick external peptidoglycan cell wall and cell membrane of the Gram-positive Bacillus subtilis, before ejecting its dsDNA genome through its tail into the bacterial cytoplasm. The tail of bacteriophage phi29 is noncontractile and approximately 380 A long. A 1.8-A resolution crystal structure of gene product 13 (gp13) shows that this tail protein has spatially well separated N- and C-terminal domains, whose structures resemble lysozyme-like enzymes and metallo-endopeptidases, respectively. CryoEM reconstructions of the WT bacteriophage and mutant bacteriophages missing some or most of gp13 shows that this enzyme is located at the distal end of the phi29 tail knob. This finding suggests that gp13 functions as a tail-associated, peptidoglycan-degrading enzyme able to cleave both the polysaccharide backbone and peptide cross-links of the peptidoglycan cell wall. Comparisons of the gp13(-) mutants with the phi29 mature and emptied phage structures suggest the sequence of events that occur during the penetration of the tail through the peptidoglycan layer.