Bacterial realm—Phytophalum Leptophyllum
<h1 class="pgc-h-arrow-right" data-track="3" >1</h1>
Mollicutes
Acholeplasmatales
Acholeplasmataceae
Acholeplasma
Phytoplasma*
Anaeroplasmatales
Anaeroplasmataceae
Anaeroplasma
Sterol-free protosite (Asteroleplasma)
Order Protomoplasmatales (Entomoplasmatales)
Zooplasma (Entomoplasmataceae)
Genus Zetoplasma (Entomoplasma)
Mesoplasma
Spiroplasmataceae (Spiroplasmataceae)
Spiroplasma
Mycoplasmatales
Mycoplasmataceae (Mycoplasmataceae)
(Allobaculum)
(Eperythrozoon)
(Haemobartonella)
Mycoplasma (Mycoplasma)
Ureaplasma (Ureaplasma)
The purpose is undecided
Erysipelothrichaceae
(Bulleidia)
Erysipelothrix
(Holdemania)
(Solobacterium)
<h1 class="pgc-h-arrow-right" data-track="32" >2</h1>
Spiroplasma is a family/genus of the order Protoplasma in the order Mollicutes. Spironoides have no cell wall, and like other microorganisms under the soft membrane bacterium, the metabolic process is simple, parasitic life, the colony form is "omelette" shape, the genome is small, but its form is different from the typical soft membrane bacterium microbial Mycoplasma, which is spiral-shaped, and it also takes a spiral-shaped route when moving. Most of Spirosomycetes is found in the intestines of insects, hemolymm, or in the phloem of plants. Culturing Spiroplasma in vitro requires the use of a special enrichment medium with a typical incubation temperature of 30 degrees instead of 37 degrees. However, some species in the genus Spiroplasma mirum, which can cause cataracts and neurological damage in lactating mice, are best suited to grow at 37 degrees. The most well-studied spiroplasmas are Spiroplasma citri, which induces Citrus stubborn disease, and Spiroplasma kunkelii, corn stunt Disease.
<h1 class="pgc-h-arrow-right" data-track="34" >(1) pathogenicity to humans</h1>
Some views are currently that spiroplasma may cause contagious spongiform encephalopathy, but this view is controversial. This view was proposed by Dr. Bastian, but other researchers have not been able to repeat his work. The currently widely accepted view is that contagious spongiform encephalopathy is caused by prions. A 2006 study using hamsters as animal models showed that spiroplasma did not cause infectious spongiform encephalopathy, while Bastian et al., who espoused spiroplasma causing infectious spongiform encephalopathy, designed another study to refute it: First, they isolated a spironas from tissue infected with infectious spongiform encephalopathy. They then cultured the spironoids on cell-free medium and injected them into ruminants, who were found to have infectious spongiform encephalopathy.
<h1 class="pgc-h-arrow-right" data-track="36" >(2) relationship with insects</h1>
Many of the spiroplasma are endophytic symbiotic bacteria in Drosophila, and their mechanisms of influencing the host are similar to Wolbachia. The current study has found that a snail protoplasma in a fruit fly can prevent a nematode from parasitizing in fruit flies, providing a good research model for evolution in symbiosis. In addition, Spiroplasma can restore the fertility of female Fruit flies infected with nematodes. The researchers speculate that this spiroplasma can kill pathogens in Fruit flies. In addition to fruit flies, snails have also been found in arthropods such as butterflies. The snail protoplasm in danaus chrysippus kills male offspring, eventually resulting in the butterfly having far more females than males, producing a series of interesting population genetics phenomena.
<h1 class="pgc-h-arrow-right" data-track="38" > mycoplasma</h1>
Mycoplasma is a class of minimal prokaryotes without a cell wall structure, between independent and intracellular parasitic life. Many species can cause disease to humans and animals, and some saprophytes live in soil, sewage and compost. It is a pseudophylla that can form very small colonies on the medium. Because they do not have cell walls, many common antibiotics, such as penicillin or beta-lactam antibiotics, are ineffective against Mycoplasma. Many species of Mycoplasma can cause disease, such as Mycoplasma pneumoniae, which is the causative agent of certain atypical pneumonia and other respiratory diseases. Mycoplasma genitalium causes inflammation of the pelvic cavity.
A few mycoplasmas can live freely in still water, but most are found in the digestive, respiratory, and genitourinary tracts of humans and animals, which can cause disease. Some mycoplasmas can cause plant diseases.
< h1 class="pgc-h-arrow-right" data-track="41" >(1) feature</h1>
At present, more than 100 kinds of Mycoplasma have been discovered, belonging to the family of soft membrane bacteria. Clostridium parasitizes humans and other plants and animals (including insects), but can also form a partial symbiosis. Cholesterol is necessary for the survival of Mycoplasma and other species of Flex. The ideal survival temperature for Mycoplasma is the body temperature of the host, or the temperature of the external environment when the host loses the function of regulating the temperature of the body. Analysis of RNA sequences and genes from 16S ribosomes indicates that Clostridium beijerinckii is very close to Lactobacillus and Clostridium beijerinckii.
<h1 class="pgc-h-arrow-right" data-track="43" >(1) cell structure</h1>
Mycoplasma and its similar species lack cell walls, but the body retains a certain shape. The specific shape of the cells may enable Mycoplasma to reproduce on its own in different environments.
For example, Mycoplasma pneumoniae extends from its own granuloid cells to a "tip structure" that attaches to host cells, helps glide on solid surfaces, and plays an important role in cell division. Mycoplasma pneumoniae is very tiny and has a variety of shapes, but is roughly like a longitudinally cut round-bottom flask.
Mycoplasma is unique among all bacteria and requires sterols to maintain the stability of cell membranes. The sterols required for Mycoplasma come from the external environment and are usually the animal host. Mycoplasma's genome is generally only 0.58-1.38 million bases, making its biosynthetic capacity weak and it must rely on the host for synthesis. In addition, the codon UGA in the mycoplasma genetic code can be compiled into tryptophan, rather than the general milky white termination code.
< h1 class="pgc-h-arrow-right" data-track="47" >(2) staining characteristics</h1>
Because it has no cell wall, it is gram-negative, and its morphology is easy to change, it is sensitive to osmotic pressure, and it is not sensitive to antibiotics that inhibit cell wall synthesis.
< h1 class="pgc-h-arrow-right" data-track="49" >(3) colony characteristics</h1>
Colonies are small (0.1 to 1.0 mm in diameter) and have a characteristic "omelet" shape on the surface of the solid medium.
<h1 class="pgc-h-arrow-right" data-track="51" >(4) breeding method</h1>
Propagation is carried out in a common way such as bisection or budding.
<h1 class="pgc-h-arrow-right" data-track="53" >(5) Drug tolerance</h1>
Because there is no cell wall, it is suitable for beta lactam (ex. penicillin etc.) It is not sensitive to drugs that destroy cell walls such as glycopeptides, but is very sensitive to antibiotics that inhibit protein biosynthesis, such as erythromycin, tetracycline, etc., and antibiotics that destroy the structure of cell membranes containing steroidal structures (such as amphotericin, nystatin, etc.). But in this class, mycoplasma hominis (Mycoplasma hominis) for macrocycline (ex. erythromycin etc.) Naturally resistant.
<h1 class="pgc-h-arrow-right" data-track="55" >(6) has a smaller genome</h1>
The genetic genome of Mycoplasma is very small, only about 0.6 to 1.1 Mb, about 1/4 to 1/5 of E. coli. The genome of Mycoplasma pneumoniae is only 0.81Mb. The genome of Mycoplasma genitalium is smaller, with only 0.58Mb and 470 genes.
<h1 class="pgc-h-arrow-right" data-track="57" >(2) colony culture</h1>
In 1898, Nocard and Roux cultivated the bacteria that caused Contagious bovine pleuropneumonia (CBPP), which at the time caused severe mass infections in cattle. Infectious pleural pneumonia is caused by filamentous biotype colonies (SC) in Mycoplasma mycoides, and Nocard and Rux were the first people in history to cultivate Mycoplasma. However, due to the complex growth conditions of Mycoplasma, the cultivation of bacteria is still difficult.
< h1 class="pgc-h-arrow-right" data-track="59" > (3) tiny genomes</h1>
Thanks to recent advances in molecular biology and genomics, mycoplasma with simple genetic structures, especially Mycoplasma pneumoniae and its close relative Mycoplasma genitalium, have attracted considerable attention. The scientists published the complete genome sequence of Mycoplasma genitalis, stating that the strain is one of the organisms with the smallest genome and is able to exist independently. Later, the genome sequence of Mycoplasma pneumoniae was also published. Mycoplasma pneumoniae is the first time in the history of gene sequencing that a database of plascoplasm is sequenced by primer walking, rather than the traditional shotgun sequencing method. Scientists continue to study mycoplasma in genomics and proteomics, trying to understand the so-called Cynthia artificial life, catalog the structure of cellular proteins, and continue to use the advantages of the tiny genomes of these organisms to conduct vast biological research.
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