P15 and P3, the Tail Completion Proteins of Bacteriophage T4, Both Form Hexameric Rings
AUTOR(ES)
Zhao, Li
FONTE
American Society for Microbiology
RESUMO
Two proteins, gp15 and gp3 (gp for gene product), are required to complete the assembly of the T4 tail. gp15 forms the connector which enables the tail to bind to the head, whereas gp3 is involved in terminating the elongation of the tail tube. In this work, genes 15 and 3 were cloned and overexpressed, and the purified gene products were studied by analytical ultracentrifugation, electron microscopy, and circular dichroism. Determination of oligomerization state by sedimentation equilibrium revealed that both gp15 and gp3 are hexamers of the respective polypeptide chains. Electron microscopy of the negatively stained P15 and P3 (P denotes the oligomeric state of the gene product) revealed that both proteins form hexameric rings, the diameter of which is close to that of the tail tube. The differential roles between gp15 and gp3 upon completion of the tail are discussed.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=148078Documentos Relacionados
- Bacteriophage T7 helicase/primase proteins form rings around single-stranded DNA that suggest a general structure for hexameric helicases.
- Suppressors of mutations in the bacteriophage T4 gene coding for both RNA ligase and tail fiber attachment activities.
- Purification and characterization of the SegA protein of bacteriophage T4, an endonuclease related to proteins encoded by group I introns.
- Isolation and characterization of the bacteriophage T4 tail-associated lysozyme.
- Transfection of Escherichia coli Spheroplasts II. Relative Infectivity of Native, Denatured, and Renatured Lambda, T7, T5, T4, and P22 Bacteriophage DNAs