Name: spirochete shape, motion, and disease
Uploaded: 2025-06-12T09:21:19.000Z
Duration: 1 min 30 s
Channel: JoVE

Spirochäten sind gramnegative, gewundene Bakterien, die in den Stamm der Spirochäten eingeordnet werden. Endoflagellen in Spirochäten erzeugen korkenzieherartige Bewegungen, die Bewegungen durch viskose Materialien oder Gewebe ermöglichen. Die Gattung Spirochaeta umfasst anaerobe und fakultativ aerobe Spirochäten, die in Süßwasser, Sedimenten und Ozeanen freileben. Zu den bemerkenswerten Arten gehören Spirochaeta plicatilis aus sulfidischen Süßwasser- und Meeresumgebungen. Cristispira ist eine Gattung von Spirochäten, die im kristallinen Stil vieler Muscheln wie Muscheln, Muscheln und Austern vorkommt. Die Gattung Treponema umfasst anaerobe oder mikroaerophile Spirochäten, die kommensale oder Krankheitserreger von Mensch und Tier sind, wie z. B. Treponema denticola, die in der menschlichen Mundhöhle häufig vorkommen. Viele Arten der Gattung Borrelien sind pathogen. Borrelia burgdorferi zum Beispiel verursacht die Lyme-Borreliose, die durch Zecken übertragen wird. Die Gattungen Leptospira und Leptonema sind streng aerobe Spirochäten, die langkettige Fettsäuren wie Ölsäure aus dem Gewebe ihres Wirts oder der Umwelt oxidieren, um ihr Wachstum zu unterstützen. Leptospira interrogans ist beim Menschen parasitär und verursacht Leptospirose.

bakterien phylum spirochäten

Bacterial Phylum Spirochaetes

Spiroch&#228;ten, einzigartige Bakterien des Stammes Spirochaetes, sind gramnegativ, beweglich, eng gewunden, schlank und flexibel. Sie kommen in aquatischen Sedimenten und bei Tieren vor, wobei einige Krankheiten wie Syphilis verursachen. Spiroch&#228;ten werden basierend auf Lebensraum, Pathogenit&#228;t, Phylogenie und andere Eigenschaften in acht Gattungen eingeteilt.
Ihre charakteristische Beweglichkeit entsteht durch Endoflagellen, die sich im Periplasma der Zelle befinden. Diese Endoflagellen sind an den Zellpolen verankert und verlaufen entlang der Zelll&#228;nge, umh&#252;llt von einer flexiblen &#228;u&#223;eren H&#252;lle. Wenn sich die Endoflagellen drehen, erzeugen sie eine Torsion, wodurch sich die Zelle biegt und sich schraubenartig bewegt &#8211; eine Bewegung, die das Eindringen in viskoses Material oder Gewebe erleichtert. Spiroch&#228;ten werden oft mit Spirillen verwechselt &#8211; helikale, st&#228;bchenf&#246;rmige Zellen mit polaren Flagellen. Im Gegensatz zu Spiroch&#228;ten besitzen Spirillen keine &#228;u&#223;ere H&#252;lle, keine Endoflagellen und zeigen keine Schraubenbewegung. Spirillen sind steifer und gr&#246;&#223;er, w&#228;hrend Spiroch&#228;ten d&#252;nn (etwa 0,5 &#956;m) und hochflexibel sind.
Die Gattung Spirochaeta umfasst freilebende, anaerobe und fakultativ aerobe Spiroch&#228;ten, die in S&#252;&#223;wasser, Sedimenten und Ozeanen vorkommen. Spirochaeta plicatilis bewohnt sulfidhaltige S&#252;&#223;wasser- und Meeresumgebungen und besitzt B&#252;ndel von Endoflagellen um ihren gewundenen protoplasmatischen Zylinder. Spirochaeta stenostrepta, ein obligat anaerobes Bakterium in H_2S -reichen Schl&#228;mmen, fermentiert Zucker zu Ethanol, Acetat, Laktat, CO_2 und H_2.
Die Gattung Cristispira, die nur im kristallinen Stiel, einem Teil des Verdauungstrakts von Weichtieren wie Muscheln und Austern, vorkommt, unterst&#252;tzt die Nahrungsverarbeitung im Verdauungstrakt dieser Tiere. Cristispira wurde sowohl in S&#252;&#223;wasser- als auch in Meeresweichtieren nachgewiesen, konnte jedoch bislang nicht kultiviert werden; die spezifische Anpassung an diesen Lebensraum ist weiterhin unklar.
Anaerobe oder mikroaerophile Spiroch&#228;ten der Gattung Treponema sind Kommensalen oder Pathogene des Menschen und von Tieren. Treponema pallidum, der Erreger der Syphilis, ist ungew&#246;hnlich d&#252;nn (0,2 &#956;m) und weist eine flache, wellenartige Morphologie auf. Zur Diagnostik des Erregers in Syphilis-L&#228;sionen wird h&#228;ufig die Dunkelfeldmikroskopie eingesetzt.
Weitere Arten sind T. denticola, das sich in der menschlichen Mundh&#246;hle befindet und mit Zahnfleischerkrankungen assoziiert ist. Es fermentiert Aminos&#228;uren zu Acetat, CO_2, NH_3 und H_2S. T. saccharophilum lebt im Pansen von Wiederk&#228;uern und fermentiert pflanzliche Polysaccharide, w&#228;hrend T. primitia und T. azotonutricium im Darm von Termiten vorkommen und zur Cellulosefermentation, Acetogenese und Stickstofffixierung beitragen.
Die Gattung Borrelia umfasst Pathogene wie B. burgdorferi, den Erreger der Lyme-Borreliose, der durch Zecken &#252;bertragen wird. B. burgdorferi ist durch sein lineares Chromosom einzigartig und infiziert sowohl Menschen als auch Tiere. Andere Borrelia-Arten verursachen Krankheiten bei Nutztieren und V&#246;geln, typischerweise ebenfalls durch Zeckenbisse &#252;bertragen.
Die Gattungen Leptospira und Leptonema bestehen aus strikt aeroben Spiroch&#228;ten, die langkettige Fetts&#228;uren wie Oleins&#228;ure zur Energiegewinnung oxidieren. Leptospira-Arten sind d&#252;nn, fein gewunden und typischerweise an beiden Enden zu einem Haken gebogen. Die Gruppe umfasst freilebende (L. biflexa) und parasitische (L. interrogans) Arten.
St&#228;mme von L. interrogans infizieren Menschen und Tiere, wobei Nagetiere die Hauptwirte sind, obwohl auch Hunde und Schweine Tr&#228;ger sein k&#246;nnen. Beim Menschen verursacht Leptospira am h&#228;ufigsten Leptospirose, die zu Nieren- und Lebersch&#228;den, Nephritis, Gelbsucht bis hin zu Nierenversagen oder Tod f&#252;hren kann. Die Bakterien dringen durch Schleimh&#228;ute oder Hautverletzungen beim Kontakt mit infizierten Tieren ein. Haustiere wie Hunde werden routinem&#228;&#223;ig gegen Leptospirose geimpft, meist im Rahmen einer kombinierten Staupe&#8211;Leptospira-Hepatitis-Impfung.

Bakterien Phylum Spirochäten

Spiroch&#228;ten, einzigartige Bakterien des Stammes Spirochaetes, sind gramnegativ, beweglich, eng gewunden, schlank und flexibel. Sie kommen in ...

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spirochete shape, motion, and disease

Spirochetes are a group of gram-negative bacteria with a thin, flexible, tightly coiled shape. They live in aquatic sediments and in animals. Some species are harmless, while others cause diseases such as syphilis and Lyme disease.

A key feature of spirochetes is their movement. They use endoflagella, which are flagella located inside the periplasm, the space under the outer layer of the cell. These endoflagella attach at the cell poles and run along the length of the bacterium inside a flexible outer sheath. When they rotate, they twist the cell into a corkscrew-like motion that helps it move through thick liquids and tissues.

Spirochetes are often confused with spirilla. Spirilla are helical or rod-shaped cells with polar flagella, but they lack an outer sheath and endoflagella. They are also more rigid and larger. Spirochetes are much thinner, about 0.5 micrometers wide, and they bend easily.

Scientists divide spirochetes into eight genera based on habitat, pathogenicity, phylogeny, and other traits. The genus Spirochaeta includes free-living species that can live without oxygen or with little oxygen. These bacteria are found in freshwater, sediments, and oceans. Spirochaeta plicatilis lives in sulfidic freshwater and marine habitats, and its endoflagella form bundles around the coiled cell. Spirochaeta stenostrepta is an obligate anaerobe in H2S-rich muds. It ferments sugars and produces ethanol, acetate, lactate, CO2, and H2.

Cristispira is another genus. It lives in the crystalline style of mollusks such as clams and oysters and helps with food processing in their digestive tracts. It is found in both freshwater and marine mollusks, but it has not been cultured, so its special adaptation to this habitat is still unclear.

Treponema species are anaerobic or microaerophilic spirochetes that live as commensals or pathogens in humans and animals. Treponema pallidum causes syphilis and is extremely thin, about 0.2 micrometers wide, with a flat, wavy shape. Dark-field microscopy is often used to detect it in syphilitic lesions. Other species include T. denticola in the human mouth, where it is linked to gum disease, T. saccharophilum in the rumen of ruminants, and T. primitia and T. azotonutricium in termite guts, where they help with cellulose fermentation, acetogenesis, and nitrogen fixation.

The genus Borrelia includes important pathogens such as B. burgdorferi, which causes Lyme disease and spreads through tick bites. This species is unusual because it has a linear chromosome. Other Borrelia species cause disease in livestock and birds and are also transmitted by ticks.

Leptospira and Leptonema are strictly aerobic spirochetes that grow by oxidizing long-chain fatty acids such as oleic acid. Leptospira species are thin, finely coiled, and often hooked at both ends. The group includes free-living L. biflexa and parasitic L. interrogans. Rodents are the main hosts for L. interrogans, although dogs and pigs can also carry it. In humans, leptospirosis can damage the kidneys and liver and may cause nephritis, jaundice, renal failure, or death. The bacteria enter through mucous membranes or skin breaks after contact with infected animals. Dogs are vaccinated against leptospirosis with a combined distemper–leptospira–hepatitis vaccine.

Spirochete Shape, Motion, and Disease

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key terms and concepts

Explore spirochete structure, corkscrew motility, and major genera like Treponema, Borrelia, and Leptospira, plus diseases such as syphilis and Lyme disease.

Spirochete Shape, Motion, and Disease | JoVE K12

JoVE Core Microbiology provides an engaging introduction to the microbial world and its influence on health, industry, and the environment. This comprehensive collection covers key concepts such as microbial structure, metabolism, genetics, and ecology. It introduces essential laboratory techniques and microscopy methods through visually engaging animations. Corresponding scientist-in-action videos bridge classroom concepts with real-world research and applications.

microbiology

Spirochete Shape, Motion, and Disease

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