The Holliday junction resolvase RecU is required for chromosome segregation and DNA damage repair in Staphylococcus aureus.
BACKGROUND
The Staphylococcus aureus RecU protein is homologous to a Bacillus subtilis Holliday junction resolvase. Interestingly, RecU is encoded in the same operon as PBP2, a penicillin-binding protein required for cell wall synthesis and essential for the full expression of resistance in Methicillin Resistant S. aureus strains. In this work we have studied the role of RecU in the clinical pathogen S. aureus.


RESULTS
Depletion of RecU in S. aureus results in the appearance of cells with compact nucleoids, septa formed over the DNA and anucleate cells. RecU-depleted cells also show increased septal recruitment of the DNA translocase SpoIIIE, presumably to resolve chromosome segregation defects. Additionally cells are more sensitive to DNA damaging agents such as mitomycin C or UV radiation. Expression of RecU from the ectopic chromosomal spa locus showed that co-expression of RecU and PBP2 was not necessary to ensure correct cell division, a process that requires tight coordination between chromosome segregation and septal cell wall synthesis.


CONCLUSIONS
RecU is required for correct chromosome segregation and DNA damage repair in S. aureus. Co-expression of recU and pbp2 from the same operon is not required for normal cell division.
Laboratory of Bacterial Cell Biology, Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av, da República, Oeiras 2780-157, Portugal.
Ana R
AR
Pereira
Patricia
P
Reed
Helena
H
Veiga
Mariana G
MG
Pinho
D020090:Chromosome Segregation; D004260:DNA Repair; D004269:DNA, Bacterial / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D045565:Holliday Junction Resolvases / Q000378:metabolism*; D006801:Humans; D016685:Mitomycin / Q000378:metabolism; D009153:Mutagens / Q000378:metabolism; D013211:Staphylococcus aureus / Q000201:enzymology* / Q000235:genetics*; D014466:Ultraviolet Rays
D004269:DNA, Bacterial; D009153:Mutagens; D016685:Mitomycin; D045565:Holliday Junction Resolvases