What are the types of actinomycetes? What are the characteristics of actinomycetes?

Intrabasal hyphae, aerial hyphae, and spore filaments.

According to the different sites, morphology and functions of the hyphae, actinomycete hyphae can be divided into three types: intrabasal hyphae, aerial hyphae and spore filament, among which only the typical actinomycetes (such as Streptomyces) have aerial hyphae, and the original actinomycetes do not. Unlike molds, there are no erect hyphae (actinomycetes cannot be counted as bacteria to be precise, because the morphological differences are too great, and molds can be said to have no exact characteristics).

1. The spores of Streptomyces intrabasal mycelium fall on the surface of the suitable solid matrix, absorb water under suitable conditions, the spores swell, germinate, and further extend to the surrounding surface and interior of the substrate to form intrabasal mycelium, also known as primary mycelium or vegetative hyphae, with a diameter between microns and light color, and its main function is to absorb nutrients and excrete metabolites.

2. Aerial mycelium is the hyphae that grow out of the medium and extend into the space, also known as secondary mycelium. When observed under the microscope, the general aerial hyphae are darker in color, thicker than the hyphae in the base, the diameter is microns, the length is very different, the shape is straight or curved, and pigments can be produced, mostly fat-soluble pigments.

3. Spore hypha is a spore hyphae that can form spores when the aerial hyphae develop to a certain extent, and their tips are differentiated, called spore hyphae, also known as reproductive hyphae. When the spores mature, they can escape from the spore filaments and scatter.

Actinomycete species: aerial hyphae, spore filament, Streptomyces intrabasal.

1. Aerial mycelium.

Aerial hyphae (secondary hyphae) are actinomycete hyphae that extend into space outside the medium from the endobasal vegetative hyphae. Aerial hyphae are straight or branched filamentous, thicker and darker than the basal hyphae.

2. Spore filaments.

The branches of spore filaments are divided into opposite, alternate, clumped, and whorl. There are three types of patterns: straight, wavy, and spiral. Spirals are loose, tight, large and small. Most left-handed, few right-handed. The morphology and growth mode of spore filaments can be used as an important basis for the identification of strains.

3. Streptomyces intrabasal.

The spores of Streptomyces intrabasal hyphae fall on the surface of a suitable solid substrate, absorb water under suitable conditions, the spores swell, germinate, and further extend to the surrounding surface and interior of the substrate to form intrabasal hyphae, also known as primary mycelium (primary mycelium) or vegetative hyphae, with a diameter between microns and a light color.

Actinomycetes are filamentous, branched-growing prokaryotic cell-type microorganisms. There are 31 species, which normally inhabit the oral cavity, upper respiratory tract, gastrointestinal tract and genitourinary tract of humans and animals. The common ones are Actinomyces chlamidioi, Actinomyces bovis, Actinomyces endomycto, Actinomyces mucous mucoides and Actinomyces caries, among which Actinomyces weiyi, which is more pathogenic to humans.

Actinomycetes are the main producers of antibiotics, and many important antibiotics such as aminoglycosides, anthracyclines, and macrolides are produced by actinomycetes.

This is what we say about actinomycetes in our microbiology book.

Actinomycetes are very closely related to humans, people go to the hospital to see a doctor, and doctors often prescribe some antibiotic drugs such as streptomycin, oxytetracycline, tetracycline, chloramphenicol, erythromycin, gentamicin and so on. These antibiotic drugs are made for us by actinomycetes. So far, thousands of antibiotics have been found from microorganisms, of which 2 3 are produced by actinomycetes, some of which are also used in the production of vitamins and enzymes, the treatment of sewage, etc.

Therefore, although there are several actinomycetes that cause diseases in humans, animals and plants, such as human diseases and lung diseases, most actinomycetes have made great achievements in the prevention and control of diseases in humans, animals and plants.

Actinomycetes are actually a member of the bacterial family, a class of gram-positive bacteria with filamentous branched cells, named for their radial shape, actinomycetes prefer to live in slightly alkaline soils rich in organic matter, which are unique to soil"Muddy smell"It is produced by actinomycetes.

Selective isolation methods such as drying, heating, and pharmaceutical treatment allow us to sort out the beneficial actinomycete species we need from the soil.

Actinomycetes are morphologically more complex than bacteria, but they are still unicellular. Under the microscope, actinomycetes are branched filaments, and we call these filament-like structures hyphae, and the hyphae are similar in diameter to bacteria, less than 1 micron. The structure of hyphal cells is basically the same as that of bacteria.

According to the different morphology and function of the hyphae, actinomycete hyphae can be divided into three types: intrabasal hyphae, aerial hyphae and spore filament. Streptomyces is the most diverse, widely distributed and typical morphological group of actinomycetes.

The common ones are Actinomyces chlamydi, Actinomyces bovis, Actinomyces nepheri, Actinomyces mucous and Actinomyces caries and so on.

One of the most prominent properties of actinomycetes is that they can produce a large number and variety of antibiotics

1. Actinomycete is a class of terrestrial prokaryotes that mainly grow in hyphae and reproduce with spores. It gets its name because it grows radially on a solid medium.

2. Most of them have well-developed branched hyphae. The hyphae are slender, nearly as wide as rod-shaped bacteria, about microns. It can be divided into:

Vegetative hyphae, also known as matrix hyphae, have the main function of absorbing nutrients, and some can produce different pigments, which is an important basis for the identification of strains; Aerial hyphae, superimposed on vegetative hyphae, are also known as secondary hyphae.

3. Actinomycetes are widely distributed in nature, mainly in the form of spores or hyphae in soil, air and water, especially in the soil with low water content, rich organic matter, neutral or slightly alkaline soil. Actinomycetes are only a morphological classification and belong to the phylum Actinomycetes in the bacterial kingdom. The earthy smell peculiar to the soil is mainly caused by the metabolites of actinomycetes.

4. Actinomycetes are gram-positive bacteria, the nucleus is not coated with nuclear membrane, and the content of cell DNA is high (>50%), and most bacteria grow slowly, producing vegetative hyphae that can penetrate deep into the medium and aerial hyphae growing on the surface, and form asexual spores. Due to the different colors of spores, aerial bacteria and vegetative hyphae, the front and back of the colony often show different colors.

5. Most actinomycetes are easy to raise, and only some species are trace amounts of aerobic bacteria and anaerobic bacteria.

The hyphae of actinomycetes are divided into: aerial hyphae, vegetative hyphae, and spore hyphae. Actinomycetes are a group of terrestrial prokaryotes that mainly grow in hyphae and reproduce with spores.

It gets its name because it grows radially on a solid medium. Most have well-developed branched hyphae.

Hypha, a single tubular filament, is the structural unit of most fungi. It is germinated by spores into germination tubes, and then continuously grows into filamentous or tubular cells by bud tubes, which can be continuously extended and branched, with or without septum. The hyphae with a diaphragm are called septal hyphae, and the hyphae without a diaphragm are called eubalistic hyphae.

Some prokaryotes also have hyphae like actinomycetes.

Streptomyces.

Nocardia.

Actinomyces. Monospora parvis spp.

Streptocystis spp.

Streptocystis spp.

Touring actinomycetes.

The microbial bacterium Nocardia spp

Morphology: Vegetative hyphae are well developed, with a transverse septum and broken into bacilli or cocci. Aerial hyphae are present or absent. (Most of them are airless).

Main features: small colonies, cells are acid-fast or partially acid-fast.

Streptomyces

Morphology: The basal filaments are well developed, multi-branched, the aerial hyphae are branched, the aerial hyphae have long spore filaments, the spore filaments are straight, wavy or spiral-shaped, the spores are round, oval or rod-shaped, the surface is smooth or there are nodules, spikes, hairs or scales.

Key features: Many Streptomyces produce antibiotics, such as streptomycin is produced by Streptomyces gray. (

Frankia spp

Morphology: The basal hyphae are branched, and the microbial bacteria generally have no aerial mycelium, and the top or middle of the hyphae form sporangia, and the sporangia differentiate to produce sporangia spores, which are flagellar and non-motile.

Main features: Slightly good aerobacteria, symbiotic with non-leguminous plants to form root nodules fixed N2.

Actinoplanes

Morphology: The mycelium is branched, most of which are not angry filaments, forming sporangia on the basal mycelium, which are round, oval, irregularly shaped, and vary in size. The sporangia are spherical, oval, and rarely rod-shaped, and move in peripherygal or terminal flagella.

Main features: The sporangia produced have flagella that can swim.

Thermomonospora

Morphology: The basal filaments and air filaments are well developed, and the spores are single at the tip of the short spore peduncle or the end of the spore filament fork, and the basal filaments are all spores.

The main characteristics of microorganisms: facultative thermophilia, growth temperature 30-55, suitable temperature of 50.