title: Factors affecting daughter cells' arrangement during the early bacterial divisions.
abstract: On agar plates, daughter cells of Escherichia coli mutually slide and align side-by-side in parallel during the first round of binary fission. This phenomenon has been previously attributed to an elastic material that restricts apparently separated bacteria from being in string. We hypothesize that the interaction between bacteria and the underneath substratum may affect the arrangement of the daughter bacteria. To test this hypothesis, bacterial division on hyaluronic acid (HA) gel, as an alternative substratum, was examined. Consistent with our proposition, the HA gel differs from agar by suppressing the typical side-by-side alignments to a rare population. Examination of bacterial surface molecules that may contribute to the daughter cells' arrangement yielded an observation that, with disrupted lpp, the E. coli daughter cells increasingly formed non-typical patterns, i.e. neither sliding side-by-side in parallel nor forming elongated strings. Therefore, our results suggest strongly that the early cell patterning is affected by multiple interaction factors. With oscillatory optical tweezers, we further demonstrated that the interaction force decreased in bacteria without Lpp, a result substantiating our notion that the side-by-side sliding phenomenon directly reflects the strength of in-situ interaction between bacteria and substratum.
authors.affiliation: Institute of Microbiology and Immunology, National Yang-Ming University, Taipei, Taiwan, Republic of China.
authors.forename: Pin-Tzu
authors.initials: PT
authors.lastname: Su
authors.forename: Pei-Wen
authors.initials: PW
authors.lastname: Yen
authors.forename: Shao-Hung
authors.initials: SH
authors.lastname: Wang
authors.forename: Chi-Hung
authors.initials: CH
authors.lastname: Lin
authors.forename: Arthur
authors.initials: A
authors.lastname: Chiou
authors.forename: Wan-Jr
authors.initials: WJ
authors.lastname: Syu
mesh_terms: D000362:Agar / Q000378:metabolism; D001422:Bacterial Adhesion / Q000235:genetics / Q000502:physiology*; D002455:Cell Division / Q000235:genetics / Q000502:physiology; D004926:Escherichia coli / Q000235:genetics / Q000502:physiology*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000502:physiology*; D005407:Flagella / Q000235:genetics / Q000502:physiology*; D005782:Gels / Q000378:metabolism; D006820:Hyaluronic Acid / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000502:physiology; D008954:Models, Biological; D009154:Mutation
chemical_list: D029968:Escherichia coli Proteins; D005782:Gels; D008565:Membrane Proteins; D000362:Agar; D006820:Hyaluronic Acid