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

Spiroketler, Spiroketler filumunda sınıflandırılan Gram negatif, sarmal bakterilerdir. Spiroketlerdeki endoflagella, tirbuşon benzeri hareket üreterek viskoz malzemeler veya dokular arasında hareket sağlar. Spirochaeta cinsi, tatlı su, tortu ve okyanuslarda serbest yaşayan anaerobik ve fakültatif olarak aerobik spiroketleri içerir. Kayda değer türler arasında sülfidik tatlı su ve deniz ortamlarından Spirochaeta plicatilis bulunur. Cristispira, istiridye, midye ve istiridye gibi birçok çift kabuklu yumuşakçanın kristal tarzında bulunan bir spiroket cinsidir. Treponema cinsi, insan ağız boşluğunda yaygın olan Treponema denticola gibi insan ve hayvanların ortak veya patojenleri olan anaerobik veya mikroaerofilik spiroketleri içerir. Borrelia cinsindeki birçok tür patojeniktir. Örneğin Borrelia burgdorferi, keneler tarafından bulaşan Lyme hastalığına neden olur. Leptospira ve Leptonema cinsleri, oleik asit gibi uzun zincirli yağ asitlerini, büyümelerini desteklemek için konakçılarının dokularından veya çevreden oksitleyen kesinlikle aerobik spiroketlerdir. Leptospira interrogans insanlarda parazittir ve leptospiroza neden olur.

bakteri filumu: spiroketler

Bacterial Phylum Spirochaetes

Spiroketler, Spirochaetes &#351;ubesine ait &#246;zg&#252;n bakterilerdir; Gram-negatif, hareketli, s&#305;k&#305;ca k&#305;vr&#305;lm&#305;&#351;, ince yap&#305;l&#305; ve esnek organizmalard&#305;r. Su alt&#305; tortullar&#305;nda ve hayvanlar&#305;n v&#252;cutlar&#305;nda ya&#351;arlar; baz&#305; t&#252;rleri frengi (sifiliz) gibi hastal&#305;klara neden olur. Spiroketler; ya&#351;ad&#305;klar&#305; ortam, patojenlik d&#252;zeyleri, filogenetik ili&#351;kileri ve morfolojik &#246;zelliklerine g&#246;re sekiz cinse ayr&#305;l&#305;r.
Bu bakterilerin kendine &#246;zg&#252; hareket kabiliyeti, h&#252;crenin periplazmas&#305;nda yer alan endoflagellalara dayan&#305;r. Bu yap&#305;lar h&#252;cre kutuplar&#305;nda ba&#351;lar, h&#252;cre boyunca uzan&#305;r ve esnek bir d&#305;&#351; k&#305;l&#305;fla &#231;evrilidir. Endoflagellalar&#305;n d&#246;nmesi, h&#252;crede burulma olu&#351;turur ve h&#252;creyi tirbu&#351;on benzeri bir hareketle esnek &#351;ekilde ilerletir; bu sayede viskoz maddeler veya dokular i&#231;inde organizman&#305;n hareketi kolayla&#351;&#305;r. Spiroketler, polar flagellaya sahip helikal, &#231;ubuk &#351;ekilli h&#252;creler olan spirillum bakterileri ile kar&#305;&#351;t&#305;r&#305;labilir. Ancak spirillum t&#252;rlerinde d&#305;&#351; k&#305;l&#305;f, endoflagella ve tirbu&#351;on hareketi yoktur. Spirillum&#8217;lar daha rijit ve b&#252;y&#252;kt&#252;r; spiroketler ise yakla&#351;&#305;k 0.5 &#956;m &#231;ap&#305;ndad&#305;r ve olduk&#231;a esnektir.
Spirochaeta cinsi, tatl&#305; sularda, tortularda ve okyanuslarda bulunan serbest ya&#351;ayan, anaerobik ve fak&#252;ltatif aerobik spiroketleri i&#231;erir. Spirochaeta plicatilis, s&#252;lf&#252;r i&#231;eren tatl&#305; su ve deniz habitatlar&#305;nda ya&#351;ar; spiral protoplazmik silindirin &#231;evresinde endoflagella demetleri bulunur. Spirochaeta stenostrepta, H_2S a&#231;&#305;s&#305;ndan zengin &#231;amurda ya&#351;ayan zorunlu anaerobik bir t&#252;rd&#252;r ve &#351;ekerleri fermente ederek etanol, asetat, laktat, CO_2 ve H_2 &#252;retir.
Cristispira cinsi, midye ve istiridye gibi yumu&#351;ak&#231;alar&#305;n kristalin stiline &#246;zg&#252; olarak bulunan, sindirim sistemlerinde besinlerin i&#351;lenmesine yard&#305;mc&#305; olan bir spirokettir. Hem tatl&#305; su hem de deniz yumu&#351;ak&#231;alar&#305;nda bulunur, ancak k&#252;lt&#252;rde yeti&#351;tirilememi&#351;tir ve bu habitatlara &#246;zg&#252; adaptasyonu h&#226;l&#226; tam olarak anla&#351;&#305;lamam&#305;&#351;t&#305;r.
Treponema cinsindeki anaerobik veya mikroaerofilik spiroketler, insanlar ve hayvanlarda kommensal veya patojen olarak bulunur. Treponema pallidum, frengi (sifiliz) hastal&#305;&#287;&#305;n&#305;n etkenidir; al&#305;&#351;&#305;lmad&#305;k &#351;ekilde incedir (0.2 &#956;m) ve d&#252;z, dalgal&#305; bir morfolojiye sahiptir. Frengili lezyonlarda genellikle karanl&#305;k alan mikroskopisi bu bakterinin tespiti i&#231;in kullan&#305;l&#305;r.
Di&#287;er t&#252;rler aras&#305;nda olan; Treponema denticola, insan a&#287;&#305;z bo&#351;lu&#287;unda bulunur ve di&#351; eti hastal&#305;klar&#305;yla ili&#351;kilidir; amino asitleri fermente ederek asetat, CO_2, NH_3 ve H_2S &#252;retir. T. saccharophilum, gevi&#351; getiren hayvanlar&#305;n rumeninde bulunur ve bitkisel polisakkaritleri fermente eder. T. primitia ve T. azotonutricium, termitlerin ba&#287;&#305;rsaklar&#305;nda ya&#351;ar; sel&#252;loz fermantasyonu, asetogenez ve azot fiksasyonu yapar.
Borrelia cinsi, kene yoluyla bula&#351;an Lyme hastal&#305;&#287;&#305; etkeni olan B. burgdorferi gibi patojenleri i&#231;erir. B. burgdorferi, insanlar&#305; ve hayvanlar&#305; enfekte eder ve kendine &#246;zg&#252; olarak lineer kromozoma sahiptir. Di&#287;er Borrelia t&#252;rleri, &#231;iftlik hayvanlar&#305; ve ku&#351;larda hastal&#305;klara yol a&#231;ar ve genellikle kene &#305;s&#305;r&#305;&#287;&#305; ile bula&#351;&#305;r.
Leptospira ve Leptonema cinsleri, b&#252;y&#252;me i&#231;in oleik asit gibi uzun zincirli ya&#287; asitlerini oksitleyen zorunlu aerobik spiroketlerden olu&#351;ur. Leptospira t&#252;rleri ince, s&#305;k&#305; k&#305;vr&#305;ml&#305;, u&#231;lar&#305; genellikle kancaya benzer bi&#231;imde b&#252;k&#252;lm&#252;&#351; bakterilerdir. Bu grup hem serbest ya&#351;ayan (L. biflexa) hem de parazit (L. interrogans) t&#252;rler i&#231;erir.
L. interrogans su&#351;lar&#305;, ba&#351;ta kemirgenler olmak &#252;zere insanlar&#305; ve hayvanlar&#305; enfekte eder; k&#246;pekler ve domuzlar da ta&#351;&#305;y&#305;c&#305; olabilir. &#304;nsanlarda leptospirozis, Leptospira&#8217;n&#305;n neden oldu&#287;u en yayg&#305;n hastal&#305;kt&#305;r; b&#246;brek ve karaci&#287;er hasar&#305;, nefrit, sar&#305;l&#305;k ve ciddi durumlarda b&#246;brek yetmezli&#287;i veya &#246;l&#252;me yol a&#231;abilir. Bakteriler, enfekte hayvanlarla temas s&#305;ras&#305;nda mukoza zarlar&#305; veya ciltteki yar&#305;klardan v&#252;cuda girer. Evcil hayvanlar (&#246;rne&#287;in k&#246;pekler), genellikle karma a&#351;&#305; program&#305; kapsam&#305;nda distemper-leptospira-hepatit a&#351;&#305;s&#305;yla bu hastal&#305;&#287;a kar&#351;&#305; a&#351;&#305;lan&#305;r.

Bakteri filumu: Spiroketler

Spiroketler, Spirochaetes &#351;ubesine ait &#246;zg&#252;n bakterilerdir; Gram-negatif, hareketli, s&#305;k&#305;ca k&#305;vr&#305;lm&#305;&#351;, ince ...

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Microbiology

Mikrobiyoloji

Unit

Birim

Microbial Diversity

Mikrobiyal Çeşitlilik

KEY TERMS AND CONCEPTS

TEMEL TERİMLER VE KAVRAMLAR

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

three-domain system of life

How rRNA Reshaped Life's Domains

Ribosomal RNA, or rRNA, changed how scientists classify life. Sequence analysis showed three major groups of cells: eukaryotes, bacteria, and archaea. In 1978, Carl R. Woese proposed domains as a taxonomic level above kingdoms to separate these groups. Woese also showed that archaea and bacteria are not the same, even though they can look similar. The three domains differ in rRNA, membrane lipid structure, transfer RNA, and sensitivity to antibiotics. These differences helped scientists build...

microbial classification system

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Microbial classification organizes bacteria and archaea into ranked groups based on shared traits and evolutionary relationships. Scientists use phenotypic similarities, which are visible or measurable traits, and genotypic data, which comes from genetic information. The result is a hierarchy that helps place each organism in a clear taxonomic order. The ranking system starts with species and moves upward through genus, family, order, class, and finally domain. A species can include one or...

methods of classification and identification

methods-of-classification-and-identification

Bacterial ID Through Lab Tests

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modern molecular taxonomy

DNA Tools for Identifying Bacteria

DNA-based methods help scientists identify and compare bacteria with much greater precision. As sequencing becomes faster and less expensive, these tools are used in clinical, environmental, and evolutionary studies. They let researchers tell related strains apart and track how microbes spread. One important method is multilocus sequence typing, or MLST. It examines several housekeeping genes, which are essential chromosomal genes that support basic cell functions. About 450-base-pair...

applications of molecular taxonomy

Molecular Taxonomy in Bacterial Research

Molecular taxonomy in bacterial research uses DNA sequencing and DNA fingerprinting to classify bacteria more precisely. These molecular tools help scientists study bacterial diversity, evolutionary relationships, and ecological roles. They have changed how researchers identify and compare bacteria in both health and environmental studies. One major use of molecular taxonomy is resolving taxonomic ambiguities, or unclear classification cases. It can separate closely related bacteria that were...

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Proteobacteria Classes and Their Key Roles

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Planctomycetes Cell Structure and Life Cycle

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bacterial phylum verrucomicrobiota

Verrucomicrobiota Cell Structure and Traits

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bacterial phylum spirochaetes

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...

bacterial phylum cyanobacteria

Cyanobacteria and Oxygenic Photosynthesis

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Actinobacteria: Soil Bacteria and Cheese

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Firmicutes: Bacteria, Fermentation, and Spores

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Gut and Environment Bacteria in Bacteroidota

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Sulfur-Using Bacteria That Harvest Light

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hyperthermophilic bacteria

Heat-Loving Bacteria and Their Enzymes

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bacterial phylum tenericutes

Mycoplasmas and Wall-Less Bacteria

Mycoplasmas are wall-less bacteria in the phylum Tenericutes. This group includes the single class Mollicutes, a name that comes from the Latin mollis, meaning soft. These bacteria are among the smallest known. They are often called mycoplasmas because the genus Mycoplasma includes many well-known human pathogens. Mycoplasmas cannot stain gram-positive because they lack cell walls. Even so, they are related to the Firmicutes. They often live closely with animal or plant hosts. Their small...

other unique bacteria

Magnetotactic and DNA-Resistant Bacteria

Magnetotactic bacteria move using Earth’s magnetic field, and some bacteria are known for extreme DNA repair. These unusual microbes show two very different survival strategies. One uses magnetic particles to guide movement. The other can recover after severe radiation damage. Magnetotaxis is the directed movement seen in magnetic bacteria. It depends on magnetosomes, which are chains of magnetic particles made of magnetite (Fe₃O₄) or greigite (Fe₃S₄). A protein scaffold keeps these particles...

overview of archaea

Archaea Cell Structure and Metabolism

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Archaea Extremes: Euryarchaeota

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diversity of archaea ii

New Archaea Phyla and Their Roles

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diversity of archaea iii

Crenarchaeota in Extreme Hot Springs

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diversity of archaea iv

How Hyperthermophilic Archaea Survive Heat

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overview of fungi

Fungi Structure, Reproduction, and Roles

Fungi are eukaryotes that are more closely related to animals than to other eukaryotes. Their cell walls contain chitin, a polysaccharide that gives strength, and glucans, which add flexibility and support. Some fungi also use mannans and galactosans in place of, or along with, chitin. These features help fungi live in acidic places and survive high osmotic pressure. Fungi can be unicellular, like yeasts, or multicellular. In multicellular fungi, the body forms a mycelium, which is a branching...

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Zygomycota: Spores, Hyphae, and Roles

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fungal phylum microsporidia

Microsporidia Spores and Host Infection

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Ascomycota: Sac Fungi and Their Spore Cycle

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fungal phylum basidiomycota

Basidiomycota: Mushrooms, Spores, and Ecological Roles

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Red Algae Pigments, Shapes, and Uses

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green algae

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other algae

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diversity of protists i

Excavata Protists and Their Adaptations

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diversity of protists ii

Alveolates: Ciliates, Dinoflagellates, Apicomplexans

Alveolates are protists with tiny sacs called alveoli beneath the cell membrane. These sacs may help control water balance by limiting how much water moves in and out of the cell. In dinoflagellates, alveoli may also act like armor plates. The three main alveolate groups are ciliates, dinoflagellates, and apicomplexans. Ciliates move with cilia, which are short hair-like structures that can cover the whole cell or appear in rows or tufts. One well-known ciliate is Paramecium, which uses cilia...

diversity of protists iii

Rhizaria: Pseudopods, Tests, and Skeletons

Rhizaria are unicellular protists with threadlike pseudopodia, which are thin cytoplasmic extensions used for movement and feeding. Their amoeboid shape once caused taxonomic confusion, but molecular phylogenetics has since shown where they fit on the evolutionary tree. This group includes Chlorarachniophyta, Radiolaria, and Foraminifera, and each lineage has adapted to a different ecological niche and metabolic strategy. Chlorarachniophyta are unicellular phototrophic protists found in marine...

diversity of protists iv

Amoebozoa: Movement and Life Cycles

Amoebozoa are a diverse group of terrestrial and aquatic protists. They move and feed with lobe-shaped pseudopodia. This feature sets them apart from Rhizaria, which have threadlike pseudopodia. The group includes gymnamoebas, entamoebas, and the plasmodial and cellular slime molds. Phylogenetic evidence also shows that Amoebozoa split from a lineage that later gave rise to fungi and animals. Gymnamoebas are free-living protists that live in water and soil. They move by amoeboid movement,...

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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