Microchannel-nanopore device for bacterial chemotaxis assays.
Anal Chem
; 82(22): 9357-64, 2010 Nov 15.
Article
em En
| MEDLINE
| ID: mdl-20961116
ABSTRACT
Motile bacteria bias the random walk of their motion in response to chemical gradients by the process termed chemotaxis, which allows cells to accumulate in favorable environments and disperse from less favorable ones. In this work, we describe a simple microchannel-nanopore device that establishes a stable chemical gradient for chemotaxis assays in ≤1 min. Chemoattractant is dispensed by diffusion through 10 nm diameter pores at the intersection of two microchannels. This design requires no external pump and minimizes the effect of transmembrane pressure, resulting in a stable, reproducible gradient. The microfluidic platform facilitates microscopic observation of individual cell trajectories, and chemotaxis is quantified by monitoring changes in cell swimming behavior in the vicinity of the intersection. We validate this system by measuring the chemotactic response of an aquatic bacterium, Caulobacter crescentus, to xylose concentrations from 1.3 µM to 1.3 M. Additionally, we make an unanticipated observation of increased turn frequency in a chemotaxis-impaired mutant which provides new insight into the chemotaxis pathway in C. crescentus.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Quimiotaxia
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Caulobacter crescentus
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Técnicas Analíticas Microfluídicas
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Nanoporos
Idioma:
En
Revista:
Anal Chem
Ano de publicação:
2010
Tipo de documento:
Article
País de afiliação:
Estados Unidos