Bacillus subtilis strain deficient for the protein-tyrosine kinase PtkA exhibits impaired DNA replication.
Bacillus subtilis has recently come into the focus of research on bacterial protein-tyrosine phosphorylation, with several proteins kinases, phosphatases and their substrates identified in this Gram-positive model organism. B. subtilis protein-tyrosine phosphorylation system PtkA/PtpZ was previously shown to regulate the phosphorylation state of UDP-glucose dehydrogenases and single-stranded DNA-binding proteins. This promiscuity towards substrates is reminiscent of eukaryal kinases and has prompted us to investigate possible physiological effects of ptkA and ptpZ gene inactivations in this study. We were unable to identify any striking phenotypes related to control of UDP-glucose dehydrogenases, natural competence and DNA lesion repair; however, a very strong phenotype of DeltaptkA emerged with respect to DNA replication and cell cycle control, as revealed by flow cytometry and fluorescent microscopy. B. subtilis cells lacking the kinase PtkA accumulated extra chromosome equivalents, exhibited aberrant initiation mass for DNA replication and an unusually long D period.
Petranovic
Dina
D
Center for Microbial Biotechnology, BioCentrum, Technical University of Denmark, DK-2800 Lyngby, Denmark.
Michelsen
Ole
O
Zahradka
Ksenija
K
Silva
Catarina
C
Petranovic
Mirjana
M
Jensen
Peter Ruhdal
PR
Mijakovic
Ivan
I
D001412:Bacillus subtilis / Q000201:enzymology / Q000235:genetics* / Q000648:ultrastructure; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D004261:DNA Replication; D004268:DNA-Binding Proteins / Q000235:genetics; D005434:Flow Cytometry; D015964:Gene Expression Regulation, Bacterial; D011505:Protein-Tyrosine Kinases / Q000172:deficiency* / Q000378:metabolism
D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D011505:Protein-Tyrosine Kinases