In vitro assembly of the T=13 procapsid of bacteriophage T5 with its scaffolding domain.

ABSTRACT: The Siphoviridae coliphage T5 differs from other members of this family by the size of its genome (121 kbp) and by its large icosahedral capsid (90 nm), which is organized with T=13 geometry. T5 does not encode a separate scaffolding protein, but its head protein, pb8, contains a 159-residue aminoterminal scaffolding domain (Delta domain) that is the mature capsid. We have deciphered the early events of T5 shell assembly starting from purified pb8 with its Delta domain (pb8p). The self assembly of pb8p is regulated by salt conditions and leads to structures with distinct morphologies. Expanded tubes are formed in the presence of NaCl, whereas Ca(2+) promotes the association of pb8p into contracted tubes and procapsids. Procapsids display an angular organization and 20-nm-long internal radi

SUBMITTER: Huet A 

PROVIDER: S-EPMC2937613 | biostudies-literature | 2010 Sep

REPOSITORIES: biostudies-literature