Homologs of the eukaryotic transcription coactivator PC4, which also functions in DNA repair and oxidative stress, were recently identified in prokaryotes. Crystallographic analysis of BPSL1147, a putative homolog from the pathogen Burkholderia pseudomallei K96243, reveals a highly conserved core structure and suggests a nucleic acid binding mode similar to that of PC4. Knock-out and complementation experiments do not reveal distinguishing phenotypes under normal growth conditions or in the presence of H2O2, arguing against a critical role in repair or the oxidative stress response of Burkholderia. These results may reflect redundancy or point at a bacteriophage origin of Burkholderia PC4 homologs.
Keywords: Bacteriophage; DNA replication, recombination and repair; Oxidative stress; Positive cofactor 4; Transcription.