Send to

Choose Destination
EMBO J. 1994 May 15;13(10):2472-80.

A mutant cysteinyl-tRNA synthetase affecting timing of chromosomal replication initiation in B. subtilis and conferring resistance to a protein kinase C inhibitor.

Author information

Institut de Génétique et Microbiologie, URA CNRS 1354, Université Paris XI, Orsay, France.


A Bacillus subtilis mutant spnA95 was isolated as resistant at 30 degrees C to the protein kinase C (PKC) inhibitor, sphinganine, and temperature sensitive for growth. As deduced by flow cytometry measurements, the mutant has a 35% reduced initiation mass at permissive temperature, resulting in initiation of DNA replication much earlier in the cell cycle than in the wild type. This modification is accompanied by a change in cell size, as determined by phase-contrast microscopy and flow cytometry. Therefore, this strain displays the characteristics of a novel cell clock mutant. spnA is a newly identified gene in B.subtilis and was shown to encode a cysteinyl-tRNA synthetase. At non-permissive temperature, the mutant was defective in the synthesis of P70, a protein with several characteristics of PKC (a cysteine-rich protein). As one possibility, we propose that the altered timing of replication may be due to the reduced synthesis of specific cysteine-rich proteins normally involved in controlling chromosomal replication initiation in B. subtilis.

[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for PubMed Central Icon for Norwegian BIBSYS system
Loading ...
Support Center