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

Las espiroquetas son bacterias gramnegativas, enrolladas, clasificadas en el filo Spirochaetes.Los endoflagelos en las espiroquetas producen un movimiento similar al de un sacacorchos, lo que permite el movimiento a través de materiales o tejidos viscosos.El género Spirochaeta incluye espiroquetas anaeróbicas y facultativamente aeróbicas que viven libremente en agua dulce, sedimentos y océanos.Las especies notables incluyen Spirochaeta plicatilis de ambientes marinos y de agua dulce sulfídicos.Cristispira es un género de espiroquetas que se encuentran en el estilo cristalino de muchos moluscos bivalvos como almejas, mejillones y ostras.El género Treponema incluye espiroquetas anaeróbicas o microaerofílicas que son comensales o patógenos de humanos y animales, como Treponema denticola, común en la cavidad oral humana.Muchas especies del género Borrelia son patógenas. La Borrelia burgdorferi, por ejemplo, causa la enfermedad de Lyme, que es transmitida por garrapatas.Los géneros Leptospira y Leptonema son espiroquetas estrictamente aeróbicas que oxidan los ácidos grasos de cadena larga, como el ácido oleico, de los tejidos de su huésped o del medio ambiente para apoyar su crecimiento. Leptospira interrogans es un parásito en los seres humanos y causa leptospirosis.

filo bacteriano: spirochaetes

Bacterial Phylum Spirochaetes

Las espiroquetas, bacterias &#250;nicas del filo Spirochaetes, son Gram negativas, m&#243;viles, fuertemente enrolladas, delgadas y flexibles. Habitan sedimentos acu&#225;ticos y animales, y algunas causan enfermedades como la s&#237;filis. Las espiroquetas se clasifican en ocho g&#233;neros seg&#250;n su h&#225;bitat, patogenicidad, filogenia y caracter&#237;sticas morfol&#243;gicas.
Su motilidad distintiva se debe a la presencia de endoflagelos localizados en el periplasma celular. Estos endoflagelos se anclan en los polos celulares y se extienden a lo largo de la c&#233;lula, recubiertos por una vaina externa flexible. Al rotar, los endoflagelos generan una torsi&#243;n que provoca el movimiento en forma de sacacorchos, facilitando su desplazamiento a trav&#233;s de medios viscosos o tejidos. Frecuentemente se confunden con espirilos, c&#233;lulas helicoidales y en forma de bast&#243;n con flagelos polares. A diferencia de las espiroquetas, los espirilos no poseen vaina externa ni endoflagelos, y carecen de motilidad en sacacorchos. Los espirilos son m&#225;s r&#237;gidos y grandes, mientras que las espiroquetas son m&#225;s delgadas (aproximadamente 0,5 &#956;m) y altamente flexibles.
El g&#233;nero Spirochaeta incluye espiroquetas de vida libre, anaerobias y aerobias facultativas, presentes en agua dulce, sedimentos y oc&#233;anos. Spirochaeta plicatilis habita ambientes sulfh&#237;dricos dulciacu&#237;colas y marinos, con haces de endoflagelos alrededor de su cilindro protoplasm&#225;tico. Spirochaeta stenostrepta, anaerobia estricta de lodos ricos en H_2S, fermenta az&#250;cares produciendo etanol, acetato, lactato, CO_2 y H_2.
El g&#233;nero Cristispira es exclusivo del estilo cristalino de moluscos como almejas y ostras, donde contribuye al procesamiento de alimentos en su tracto digestivo. Presente en moluscos de agua dulce y marinos, Cristispira no ha sido cultivada, y su adaptaci&#243;n espec&#237;fica a dicho h&#225;bitat permanece sin esclarecer.
Espiroquetas anaerobias o microaerof&#237;licas del g&#233;nero Treponema son comensales o pat&#243;genos de humanos y animales. Treponema pallidum, agente causal de la s&#237;filis, es extremadamente delgada (0,2 &#956;m) y presenta una morfolog&#237;a ondulada y plana. La microscop&#237;a de campo oscuro se emplea com&#250;nmente para detectarla en lesiones sifil&#237;ticas.
Otras especies incluyen T. denticola, hallada en la cavidad oral humana y asociada con enfermedades periodontales. Fermenta amino&#225;cidos generando acetato, CO_2, NH_3 y H_2S. T. saccharophilum reside en el rumen de rumiantes, fermentando polisac&#225;ridos vegetales, mientras que T. primitia y T. azotonutricium habitan en intestinos de termitas, participando en la fermentaci&#243;n de celulosa, acetog&#233;nesis y fijaci&#243;n de nitr&#243;geno.
El g&#233;nero Borrelia incluye pat&#243;genos como B. burgdorferi, causante de la enfermedad de Lyme, transmitida por garrapatas. B. burgdorferi es singular por su cromosoma lineal y puede infectar tanto a humanos como a animales. Otras especies de Borrelia causan enfermedades en ganado y aves, tambi&#233;n transmitidas por garrapatas.
Los g&#233;neros Leptospira y Leptonema comprenden espiroquetas estrictamente aerobias que oxidan &#225;cidos grasos de cadena larga, como el &#225;cido oleico, para crecer. Las especies de Leptospira son delgadas, finamente enrolladas y con extremos generalmente curvados en forma de gancho. El grupo incluye especies de vida libre (L. biflexa) y par&#225;sitas (L. interrogans).
Las cepas de L. interrogans infectan tanto a humanos como a animales, siendo los roedores sus principales hu&#233;spedes, aunque tambi&#233;n los perros y cerdos pueden ser portadores. En humanos, la leptospirosis es la afecci&#243;n m&#225;s com&#250;n causada por Leptospira, provocando da&#241;o hep&#225;tico y renal, nefritis, ictericia y, potencialmente, insuficiencia renal o muerte. Las bacterias ingresan a trav&#233;s de mucosas o heridas en la piel al entrar en contacto con animales infectados. En animales dom&#233;sticos, como los perros, se administra una vacuna combinada contra moquillo, leptospira y hepatitis.

Filo bacteriano: Spirochaetes

Las espiroquetas, bacterias &#250;nicas del filo Spirochaetes, son Gram negativas, m&#243;viles, fuertemente enrolladas, delgadas y flexibles. Habitan ...

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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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