Abstract |
Initiation of Myxococcus xanthus multicellular development requires integration of information concerning the cells' nutrient status and density. A gain-of-function mutation, sasB7, that bypasses both the starvation and high cell density requirements for developmental expression of the 4521 reporter gene, maps to the sasS gene. The wild-type sasS gene was cloned and sequenced. This gene is predicted to encode a sensor histidine protein kinase that appears to be a key element in the transduction of starvation and cell density inputs. The sasS null mutants express 4521 at a basal level, form defective fruiting bodies, and exhibit reduced sporulation efficiencies. These data indicate that the wild-type sasS gene product functions as a positive regulator of 4521 expression and participates in M. xanthus development. The N terminus of SasS is predicted to contain two transmembrane domains that would locate the protein to the cytoplasmic membrane. The sasB7 mutation, an E139K missense mutation, maps to the predicted N-terminal periplasmic region. The C terminus of SasS contains all of the conserved residues typical of the sensor histidine protein kinases. SasS is predicted to be the sensor protein in a two-component system that integrates information required for M. xanthus developmental gene expression.
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Authors | C Yang, H B Kaplan |
Journal | Journal of bacteriology
(J Bacteriol)
Vol. 179
Issue 24
Pg. 7759-67
(Dec 1997)
ISSN: 0021-9193 [Print] United States |
PMID | 9401035
(Publication Type: Journal Article, Research Support, U.S. Gov't, P.H.S.)
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Chemical References |
- Bacterial Proteins
- Protein Kinases
- Histidine Kinase
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Topics |
- Alleles
- Amino Acid Sequence
- Bacterial Proteins
(genetics)
- Base Sequence
- Cloning, Molecular
- Gene Expression Regulation, Bacterial
- Gene Expression Regulation, Developmental
- Histidine Kinase
- Molecular Sequence Data
- Morphogenesis
(genetics)
- Mutation
- Myxococcales
- Myxococcus xanthus
(enzymology, genetics)
- Protein Kinases
(genetics)
- Sequence Homology, Amino Acid
- Signal Transduction
(genetics)
- Spores, Bacterial
- Transcription, Genetic
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