P2 growth restriction on an rpoC mutant is suppressed by alleles of the Rz1 homolog lysC.
Escherichia coli strain 397c carries a temperature-sensitive mutation, rpoC397, that removes the last 50 amino acids of the RNA polymerase beta' subunit and is nonpermissive for plating of bacteriophage P2. P2 gor mutants productively infect 397c and define a new gene, lysC, encoded by a reading frame that extensively overlaps the P2 lysis accessory gene, lysB. The unusual location of lysC with respect to lysB is reminiscent of the Rz/Rz1 lysis gene pair of phage lambda. Indeed, coexpression of lysB and lysC complemented the growth defect of lambda Rz/Rz1 null mutants, indicating that the LysB/C pair is similar to Rz/Rz1 in both gene arrangement and function. Cells carrying the rpoC397 mutation exhibited an early onset of P2-induced lysis, which was suppressed by the gor mutation in lysC. We propose that changes in host gene expression resulting from the rpoC397 mutation result in changes in the composition of the bacterial cell wall, making the cell more susceptible to P2-mediated lysis and preventing accumulation of progeny phage sufficient for plaque formation.
Markov
Dmitry
D
Waksman Institute and Department of Molecular Biology and Biochemistry, State University of New Jersey, Rutgers, Piscataway 08854, USA.
Christie
Gail E
GE
Sauer
Brian
B
Calendar
Richard
R
Park
Taehyun
T
Young
Ry
R
Severinov
Konstantin
K
D000595:Amino Acid Sequence; D001433:Bacteriolysis / Q000235:genetics / Q000502:physiology; D017901:Bacteriophage P2 / Q000235:genetics / Q000254:growth & development* / Q000502:physiology; D002473:Cell Wall / Q000378:metabolism; D012321:DNA-Directed RNA Polymerases / Q000235:genetics* / Q000502:physiology; D004926:Escherichia coli / Q000235:genetics* / Q000254:growth & development / Q000821:virology*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000502:physiology; D005807:Genes, Overlapping / Q000235:genetics / Q000502:physiology; D016153:Genes, Suppressor / Q000502:physiology*; D005814:Genes, Viral / Q000235:genetics / Q000502:physiology; D005816:Genetic Complementation Test; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics* / Q000502:physiology; D017384:Sequence Deletion / Q000235:genetics / Q000502:physiology; D013489:Suppression, Genetic / Q000235:genetics / Q000502:physiology; D013696:Temperature; D010948:Viral Plaque Assay; D014764:Viral Proteins / Q000235:genetics* / Q000502:physiology
D029968:Escherichia coli Proteins; D014764:Viral Proteins; C082268:Rz protein, bacteriophage lambda; C108570:beta' subunit of RNA polymerase; D012321:DNA-Directed RNA Polymerases