Nucleotide sequence of the DNA packaging and capsid synthesis geges of bacteriophage P2

Abstract

Overlapping DMA fragments containing the DNA packaging and capsid synthesis gene region ofbacterlophage P2 were cloned and sequenced. In this report we present the complete nucleotide sequence of this 6550 bp region. Each of six open reading frames found in the Interval was assigned to one of the essential genes (Q, P, O, N, M and L) by correlating genetic, physical and mutational data with DNA and protein sequence Information. Polypeptides predicted were: a capsid completion protein, gpL; the major capsid precursor, gpN; the presumed capsid scaffolding protein, gpO; the ATPase and proposed endonuclease subunits of termlnase, gpP and gpftfl, respectively; and a candidate for the portal protein, gpQ. These gene and protein sequences exhibited no homology to analogous genes or proteins of other bacteriophages. Expression of gene Q in E. coll from a plasmld caused production of a Rflr 39,000 Da protein that restored Qam34 growth. This sequence analysis found only genes previously known from analysis of conditional-lethal mutations. No new capsid genes were found. © 1991 Oxford University Press.