Functional and structural dissection of the tape measure protein of lactococcal phage TP901-1.
The tail tape measure protein (TMP) of tailed bacteriophages (also called phages) dictates the tail length and facilitates DNA transit to the cell cytoplasm during infection. Here, a thorough mutational analysis of the TMP from lactococcal phage TP901-1 (TMPTP901-1) was undertaken. We generated 56 mutants aimed at defining TMPTP901-1domains that are essential for tail assembly and successful infection. Through analysis of the derived mutants, we determined that TP901-1 infectivity requires the N-terminal 154 aa residues, the C-terminal 60 residues and the first predicted hydrophobic region of TMPTP901-1as a minimum. Furthermore, the role of TMPTP901-1in tail length determination was visualized by electron microscopic imaging of TMP-deletion mutants. The inverse linear correlation between the extent of TMPTP901-1-encoding gene deletions and tail length of the corresponding virion provides an estimate of TMPTP901-1regions interacting with the connector or involved in initiator complex formation. This study represents the most thorough characterisation of a TMP from a Gram-positive host-infecting phage and provides essential advances to understanding its role in virion assembly, morphology and infection.
School of Microbiology, University College Cork, Cork, Ireland.|APC Microbiome Institute, University College Cork, Cork, Ireland.
Jennifer
J
Mahony
School of Microbiology, University College Cork, Cork, Ireland.
Mona
M
Alqarni
School of Microbiology, University College Cork, Cork, Ireland.|APC Microbiome Institute, University College Cork, Cork, Ireland.
Stephen
S
Stockdale
Architecture et Fonction des Macromolécules Biologiques, Aix-Marseille Université, Campus de Luminy, Marseille, France.|Architecture et Fonction des Macromolécules Biologiques, Centre National de la Recherche Scientifique (CNRS), Campus de Luminy, Marseille, France.
Silvia
S
Spinelli
School of Microbiology, University College Cork, Cork, Ireland.
Marine
M
Feyereisen
Architecture et Fonction des Macromolécules Biologiques, Aix-Marseille Université, Campus de Luminy, Marseille, France.|Architecture et Fonction des Macromolécules Biologiques, Centre National de la Recherche Scientifique (CNRS), Campus de Luminy, Marseille, France.
Christian
C
Cambillau
School of Microbiology, University College Cork, Cork, Ireland.|APC Microbiome Institute, University College Cork, Cork, Ireland.
Douwe van
DV
Sinderen
D017045:Lactococcus / Q000821:virology*; D017906:Siphoviridae / Q000737:chemistry* / Q000378:metabolism; D013329:Structure-Activity Relationship; D014764:Viral Proteins / Q000737:chemistry* / Q000378:metabolism / Q000648:ultrastructure
D014764:Viral Proteins