運動超分子マシナリーが織りなす調和と多様性

真核生物
レカネ

種名:Lecane sp.
下水道局　東京都

長さ150～160μmくらい。被甲は、背部腹部ともに扁平で、卵形または卵円形でしっぽは2本ある。頭被甲内に引き込むことができる。しっぽを動かしながらフロックの周囲を移動する。食物源は主に分散状の細菌類や原生動物だが、フロック固着性の細菌も捕食する。

微生物図鑑

真核生物
しなやかに粒子間をすりぬけて

種名:Loxodes or Remanella
AL-Museum　AL-Museum

細長く先端だけが少し曲がったこの大きな繊毛虫は、横から見るとリボンのように平たい身体の向きを上手に変え、粒子の間をすり抜けて泳ぎます。

AL-Museum

真核生物
リトノツス

種名:Litonotus sp.
東京都　下水道局

大きさは70～170 μm。500μmくらいの種類もいる。全体に短い繊毛がある。口の周りにはやや長い繊毛が密集してる。前後に滑るように移動する。移動時にも形はあまり変わらない。

微生物図鑑

真核生物
リトノータス？

種名:Litonotus
AL-Museum　AL-Museum

体は細長く、口先がやや曲がって細く伸びた繊毛虫。粒子の間を、柔らかく身をくねらせ、その口を忙しくあちこちに突っ込んでは餌をあさる。方向転換する際はリボンのようで、体が扁平なことが分かる。狭い粒子の隙間には他にも様々な生き物が溢れている。

AL-Museum

原核生物
Part 1: Bacterial pathogenesis: the Listeria paradigm

種名:Listeria
Pasteur Institute　Pascale Cossart

Cossart begins her talk with an overview of microbiology and then focuses on the bacterium Listeria monocytogenes, a food-borne, intracellular pathogen. Cossart explains how Listeria enter epithelial cells, move around inside cells, and spread between cells. She describes how her lab identifed Listeria virulence genes by comparing the sequence of a non-pathogenic species of Listeria with the sequence of L. monocytogenes. They found that Listeria uses a wide variety of strategies to infect and proliferate within its host.

原核生物
Part 2: Exploring "New Microbiology" with Listeria monocytogenes

種名:Listeria
Pasteur Institute　Pascale Cossart

In Part 2, Cossart describes how modern molecular and cell biology techniques have yielded new concepts in microbiology. For example, small non-coding RNAs that are differentially expressed and necessary for virulence have been identified. Short and long antisense RNAs with multiple regulatory functions also have been found. It seems likely that these, and other newly identified mechanisms of bacterial regulation, may prove common to different bacterial species.

原核生物
Part 3: Cell biology and infection: lessons from Listeria

種名:Listeria
Pasteur Institute　Pascale Cossart

In her final talk, Cossart reviews the many cellular processes impacted during infection with Listeria. She successively discusses activation of clathrin-mediated endocytosis during bacterial entry, nucleation of actin comet-tails by bacterial ActA, post-translational modifications during infection (in particular deSUMOylation), mitochondrial targeting, and finally chromatin remodeling and epigenetic regulation during infection. Listeria is a true cell biologist, manipulating all aspects of cell function.

真核生物
イタチムシの一種

種名:Lepidodermella sp.
学習院大学　柏崎　隼

腹毛動物に属するイタチムシは、腹側に生えた繊毛の運動により固形物表面を滑走する。 学習院大学にある「血洗いの池」より採集。 微分干渉顕微鏡、ビデオ録画。再生はリアルタイム。

原核生物
Actin Filament Interacting with Listeria monocytogenes

種名:Listeria monocytogenes
Center for Cell Dynamics, University of Washington, Friday Harbor, Washington, United States of America　Professor Jonathan B. Alberts

Listeria monocytogenes moves by actin-based motility. A close-up look at the interaction of a single polymerizing filament with the bacterium based on in silico reconstitution. This filament has an artificially durable link with an ActA protein on the bacterium's surface; these links are typically very transient. The tip-clearance (drawn with a cyan line), the polymerization probability, the capping probability, and the Arp2/3 binding probability are reported at each simulation time-step

Plos Biology

分子・タンパク質
Motion initiation and persistence of actin-based motility

種名:Listeria monocytogenes
Center for Cell Dynamics, University of Washington, Friday Harbor, Washington, United States of America　Professor Jonathan B. Alberts

An animation rendered from the output of one simulation of Listeria monocytogenes motility. Microscale hops, as opposed to the nanoscale steps we investigate are apparent at this scale view. The bacterium induces an actin tail of variable density and demonstrates persistent motion.

Plos Biology