A mathematical model for distribution of bacterial cells biased by chemotaxis and its validation through comparison with observation

2018 Fiscal Year Final Research Report

• Project/Area Number: 15K05796
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Fluid engineering
• Research Institution: Tottori University
• Principal Investigator: GOTO Tomonobu 鳥取大学, 工学研究科, 教授 (00260654)
• Co-Investigator(Kenkyū-buntansha): 中井 唱 鳥取大学, 工学研究科, 准教授 (80452548)
• Project Period (FY): 2015-04-01 – 2019-03-31
• Keywords: 走化性 / ランダムウォーク / 対流拡散方程式 / 細菌 / 分布

Outline of Final Research Achievements

Microorganisms in nature distribute inhomogeneously. This partially depends on the chemotaxis, in which they sense attractant chemicals and migrate towards the favorite direction. Bacteria, the simplest creature exhibiting the chemotaxis, change their direction randomly. During the motion, a bacterial cell sense attractant chemical concentrations at two spatially different points at two times and judge whether it has approached a favorable environment or not. This process includes data comparison at two times and causes a finite time delay. We have developed a mathematical model for the existence probability of bacterial cells migrating around a chemical attractant. Moreover, we have observed Salmonella cells’ distributions around a tip of a capillary which contains serine. Comparing the calculated and observed results, we have examined the strength of chemotaxis of bacterial cells.

Free Research Field

流体力学

Academic Significance and Societal Importance of the Research Achievements

細菌はぬめりに代表されるバイオフィルムを形成して，湖沼や海，他の生物の生体内における物質循環に寄与している．また，少し大きな微生物の餌として食物連鎖の一部になっている．細菌の分布や集積速度を予測することは，バイオフィルムの成長速度や環境中における物質循環量の予測に繋がるものである．走化性によって集積する細菌の分布や集積速度を細菌単体の単純な運動モデルから求めようとした．