title: pH-gradient ion-exchange microbial cell chromatography as a simple method for microbial separation.
abstract: Selective separation of specific microbial types from a heterogeneous microbial population, such as an environmental microbial community, is an important process for microbial research and biotechnological industries. In the present study, pH-gradient ion-exchange microbial cell chromatography (PIE-MCC) was developed as a new method for microbial separation. The proposed method enables target microorganisms to be separated from a microbial community based on differences in microbial surface characteristics, because these characteristics, such as the ζ (zeta)-potential, vary among microbial cells. PIE-MCC was conducted by controlling the adhesion and detachment of microbial cells to and from the carrier surface by manipulating the pH of the running buffer. As a proof of concept, microbial cell separation via PIE-MCC was demonstrated using pure-cultured strains, model mixtures of two different pure-cultured strains, and an environmental sample targeting uncultivated microorganisms; i.e., each pure-cultured strain showed unique chromatograms; specific single species were separated from the model mixture; and a specific, uncultivated target was separated from the environmental sample. The ζ-potential of several tested strains suggested that not only electrostatic interactions, but also other factors affected microbial adhesion to the carrier surface. The newly developed method has several potential advantages compared with other techniques, not only in terms of its microbial separation capability, but also in terms of its simplicity and ability to be scaled up. Thus, the method has the potential to be widely used for a variety of purposes in the microbiology and biotechnology fields.
authors.affiliation: Institute for Sustainable Sciences and Developments, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8527, Japan. Electronic address: yoshiteruaoi@hiroshima-u.ac.jp.
authors.forename: Yoshiteru
authors.initials: Y
authors.lastname: Aoi
authors.affiliation: Department of Life Science and Medical Bio-Science, Waseda University, Shinjuku-ku, Tokyo 162-8480, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Kaneko
authors.affiliation: Department of Life Science and Medical Bio-Science, Waseda University, Shinjuku-ku, Tokyo 162-8480, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Tsuneda
mesh_terms: D001419:Bacteria / Q000737:chemistry / Q000302:isolation & purification*; D001422:Bacterial Adhesion; D002021:Buffers; D002852:Chromatography, Ion Exchange / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D055672:Static Electricity
chemical_list: D002021:Buffers
keywords: Bacterial cell chromatography; Enrichment culture; Microbial adhesion; Microbial cell chromatography; Uncultivated microorganisms; ζ-potential