Document Detail

The Azospirillum brasilense Che1 chemotaxis pathway controls swimming velocity, which affects transient cell-to-cell clumping.
MedLine Citation:
PMID:  22522896     Owner:  NLM     Status:  MEDLINE    
The Che1 chemotaxis-like pathway of Azospirillum brasilense contributes to chemotaxis and aerotaxis, and it has also been found to contribute to regulating changes in cell surface adhesive properties that affect the propensity of cells to clump and to flocculate. The exact contribution of Che1 to the control of chemotaxis and flocculation in A. brasilense remains poorly understood. Here, we show that Che1 affects reversible cell-to-cell clumping, a cellular behavior in which motile cells transiently interact by adhering to one another at their nonflagellated poles before swimming apart. Clumping precedes and is required for flocculation, and both processes appear to be independently regulated. The phenotypes of a ΔaerC receptor mutant and of mutant strains lacking cheA1, cheY1, cheB1, or cheR1 (alone or in combination) or with che1 deleted show that Che1 directly mediates changes in the flagellar swimming velocity and that this behavior directly modulates the transient nature of clumping. Our results also suggest that an additional receptor(s) and signaling pathway(s) are implicated in mediating other Che1-independent changes in clumping identified in the present study. Transient clumping precedes the transition to stable clump formation, which involves the production of specific extracellular polysaccharides (EPS); however, production of these clumping-specific EPS is not directly controlled by Che1 activity. Che1-dependent clumping may antagonize motility and prevent chemotaxis, thereby maintaining cells in a metabolically favorable niche.
Amber Bible; Matthew H Russell; Gladys Alexandre
Related Documents :
16961276 - Effects of survivin expression suppressed by short hairpin rna on mcf-7 cells.
25407926 - [(18)f]fluoromethylcholine as a chemotherapy response read-out in prostate cancer cells.
18432676 - Calcium phosphate transfection.
11290526 - Activation of class ia pi3k stimulates dna synthesis in human airway smooth muscle cells.
1917936 - Negative regulation of cell proliferation by mevalonate or one of the mevalonate phosph...
19766616 - Armand m. karow, jr.: looking back.
Publication Detail:
Type:  Journal Article; Research Support, U.S. Gov't, Non-P.H.S.     Date:  2012-04-20
Journal Detail:
Title:  Journal of bacteriology     Volume:  194     ISSN:  1098-5530     ISO Abbreviation:  J. Bacteriol.     Publication Date:  2012 Jul 
Date Detail:
Created Date:  2012-06-12     Completed Date:  2012-08-21     Revised Date:  2013-06-26    
Medline Journal Info:
Nlm Unique ID:  2985120R     Medline TA:  J Bacteriol     Country:  United States    
Other Details:
Languages:  eng     Pagination:  3343-55     Citation Subset:  IM    
Department of Biochemistry, Cellular and Molecular Biology, The University of Tennessee, Knoxville, Tennessee, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Azospirillum brasilense / genetics,  metabolism,  physiology*
Bacterial Adhesion / physiology*
Bacterial Proteins / genetics,  metabolism*
Cell Membrane / metabolism
Chemotaxis / physiology*
Gene Expression Regulation, Bacterial*
Signal Transduction
Surface Properties
Reg. No./Substance:
0/Bacterial Proteins

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Effects of the SpoVT regulatory protein on the germination and germination protein levels of spores ...
Next Document:  Complete DNA sequence analysis of enterohemorrhagic Escherichia coli plasmid pO157_2 in ?-glucuronid...