Myxococcus xanthus sasS encodes a sensor histidine kinase required for early developmental gene expression.

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.

• 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.)

Chemical References

• Bacterial Proteins
• Protein Kinases
• Histidine Kinase

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