Abstract:
:The rpoN gene encoding the transcription factor sigma54 in Myxococcus xanthus has been cloned using a heterologous rpoN probe. The sequence of the cross-hybridizing DNA confirmed the existence of an ORF 1518 bp long that encodes a well conserved member of the sigma54 family of sigma factors. Low- as well as high-stringency hybridizations detected only a single rpoN gene in the M. xanthus chromosome. In other bacteria, sigma54 is an alternative sigma, and null mutants are viable. However, all attempts to construct a strain containing a null mutation in the M. xanthus rpoN have been unsuccessful. Partial diploids of rpoN+/rpoN null are viable. Recombination experiments with such partial diploids showed the impossibility of constructing, either by segregation or by transduction, a viable null haploid under any of a wide range of growth conditions. The product of the rpoN gene, sigma54, therefore appears to be essential for growth in M. xanthus.
journal_name
Proc Natl Acad Sci U S Aauthors
Keseler IM,Kaiser Ddoi
10.1073/pnas.94.5.1979subject
Has Abstractpub_date
1997-03-04 00:00:00pages
1979-84issue
5eissn
0027-8424issn
1091-6490journal_volume
94pub_type
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