Characterization ofVibrio choleraeaerotaxis

Abstract

The ability to move toward favorable environmental conditions, called chemotaxis, is common among motile bacteria. In particular, aerotaxis has been extensively studied in Escherichia coli and was shown to be dependent on the aer and tsr genes. Three putative aer gene homologs were identified in the Vibrio cholerae genome, designated aer-1 (VC0512), aer-2 (VCA0658), and aer-3 (VCA0988). Deletion analyses indicated that only one of them, aer-2, actively mediates an aerotaxis response, as assayed in succinate soft agar plates as well as a capillary assay. Complementation studies confirmed that Aer-2 is involved in aerotaxis in V. cholerae. In addition, overexpression of aer-2 resulted in a marked increase of the aerotactic response in soft agar plates. No observable phenotypes in V. cholerae mutants deleted in the aer-1 or aer-3 genes were detected under standard aerotaxis testing conditions. Furthermore, the V. cholerae aer-1 and aer-3 genes, even when expressed from a strong independent promoter, did not produce any observable phenotypes. As found in other bacterial species, the results presented in this study indicate the presence of a secondary aerotaxis transducer in V. cholerae.

Unique core genomes of the bacterial family vibrionaceae: insights into niche adaptation and speciation

“…These proteins sense one or several biochemical stimuli and enable motile bacteria to rapidly change their tactic behavior to either move towards the stimulus or away from it [29,30]. Aer2 was recently reported to cause aerotaxic behavior in V. cholerae [31]. Aerotaxis, or energy taxis, is the movement of bacteria towards or away from oxygen, a crucial electron acceptor in the energy metabolism of many organisms.…”

Microbial Surface Colonization and Biofilm Development in Marine Environments

“…Results to date show that chemotaxis can be important (399)(400)(401)(402)(403)(404)(405), advantageous (406), or dispensable (407) for initial surface colonization, indicating possible species-or strain-specific differences in the role of chemotaxis in microbial surface interactions or surface-or environment-specific differences in microbial chemotactic responses. Energy taxis can also be important to surface colonization by certain bacteria (408)(409)(410)(411). The microenvironment near a submerged surface is highly heterogeneous in that multiple gradients exist, including gradients of oxygen, pH, osmolarity, electron donors, electron acceptors, metabolizable substrates, redox potential, and chemical cues, including chemotactic attractants or repellents (34).…”

Bacterial energy taxis: a global strategy?

“…Escherichia coli (Taylor 2007; Greer-Phillips et al 2003; Edwards et al 2006), Bacillus subtilis (Hou et al 2000), Helicobacter pylori (Croxen et al 2006; Schweinitzer et al 2008), Pseudomonas aeruginosa (Hong et al 2004b) Vibrio cholera (Boin and Hase 2007), Rhodobacter sphaeroides (Gauden and Armitage 1995), Desulfovibrio vulgaris (Fu et al 1994), Shewanella oneidensis (Baraquet et al 2009), environmental perchlorate-reducing bacteria (Sun et al 2009) and Halobacterium salinarium (Zhang et al 1996; Hou et al 2000)). Corresponding to that large variety of bacteria, their habitats and their different metabolic requirements, diverse mechanisms of energy taxis have evolved.…”