TY - JOUR
T1 - The chemotaxis-like Che1 pathway has an indirect role in adhesive cell properties of Azospirillum brasilense
AU - Siuti, Piro
AU - Green, Calvin
AU - Edwards, Amanda Nicole
AU - Doktycz, Mitchel J.
AU - Alexandre, Gladys
PY - 2011/10
Y1 - 2011/10
N2 - The Azospirillum brasilense chemotaxis-like Che1 signal transduction pathway was recently shown to modulate changes in adhesive cell surface properties that, in turn, affect cell-to-cell aggregation and flocculation behaviors rather than flagellar-mediated chemotaxis. Attachment to surfaces and root colonization may be functions related to flocculation. Here, the conditions under which A. brasilense wild-type Sp7 and che1 mutant strains attach to abiotic and biotic surfaces were examined using in vitro attachment and biofilm assays combined with atomic force microscopy and confocal microscopy. The nitrogen source available for growth is found to be a major modulator of surface attachment by A. brasilense and could be promoted in vitro by lectins, suggesting that it depends on interaction with surface-exposed residues within the extracellular matrix of cells. However, Che1-dependent signaling is shown to contribute indirectly to surface attachment, indicating that distinct mechanisms are likely underlying flocculation and attachment to surfaces in A. brasilense.
AB - The Azospirillum brasilense chemotaxis-like Che1 signal transduction pathway was recently shown to modulate changes in adhesive cell surface properties that, in turn, affect cell-to-cell aggregation and flocculation behaviors rather than flagellar-mediated chemotaxis. Attachment to surfaces and root colonization may be functions related to flocculation. Here, the conditions under which A. brasilense wild-type Sp7 and che1 mutant strains attach to abiotic and biotic surfaces were examined using in vitro attachment and biofilm assays combined with atomic force microscopy and confocal microscopy. The nitrogen source available for growth is found to be a major modulator of surface attachment by A. brasilense and could be promoted in vitro by lectins, suggesting that it depends on interaction with surface-exposed residues within the extracellular matrix of cells. However, Che1-dependent signaling is shown to contribute indirectly to surface attachment, indicating that distinct mechanisms are likely underlying flocculation and attachment to surfaces in A. brasilense.
KW - Aggregation
KW - Azospirillum brasilense
KW - Chemotaxis
KW - Flocculation
UR - http://www.scopus.com/inward/record.url?scp=80052901173&partnerID=8YFLogxK
U2 - 10.1111/j.1574-6968.2011.02366.x
DO - 10.1111/j.1574-6968.2011.02366.x
M3 - Article
C2 - 22092709
AN - SCOPUS:80052901173
SN - 0378-1097
VL - 323
SP - 105
EP - 112
JO - FEMS Microbiology Letters
JF - FEMS Microbiology Letters
IS - 2
ER -