What color does Bacillus stain?

What color does Bacillus stain?

The acid-fast bacilli will stain bright red, and the background will stain blue. Reagents used in the procedure include Ziehl–Neelsen carbol-fuchsin solution, 1% acid alcohol, and methylene blue solution [15].

How do you stain Bacillus spores?


  1. Prepare a smear of Bacillus subtilis using a darkly colored colony grown on nutrient sporulation media (NSM).
  2. Air dry the smear and heat fix it.
  3. Cover the smear with the primary stain malachite green.
  4. After the slide is cool, rinse both the top and the bottom well with water.

What stain can be used to demonstrate spores of Bacillus species?

– Endospore Stain
Welcome to Microbugz – Endospore Stain. The endospore stain is a differential stain used to visualize bacterial endospores. Endospores are formed by a few genera of bacteria, such as Bacillus . By forming spores, bacteria can survive in hostile conditions.

What color is a positive spore stain?

At the end of the staining process, vegetative cells will be pink, and endospores will be dark green.

Do all Bacillus form spores?

In all Bacillus species studied, the process of spore formation is similar, and can be divided into seven defined stages (0-VI). The vegetative cell (a) begins spore development when the DNA coils along the central axis of the cell as an “axial filament” (b).

What is Spore staining?

Abstract. Endospores staining is the type of staining to recognize the presence spore in bacterial vegetative cells. The bacterial endospores need a staining which can penetrate wall thickness of spore bacteria. A method of endospores staining is Schaeffer Fulton method that used Malachite Green.

What is the purpose of steam in Endospore staining?

The presence of endospores in a bacterial culture can be detected by staining with malachite green. Because the endospore coat is so tough, steam is used to enable dye penetration. After washing, only the endospores will retain the primary stain Malachite green.

What are the materials needed for spore staining?


  • Reagents: Malachite green, safrinin, acid alcohol.
  • stain rack.
  • hot plate.
  • paper towel (cut the size of the slide)
  • Bacillus culture on an slant or plate agar (an old culture to enhance sporulation)

What does Bacillus subtilis need to grow?

B. subtilis growth best at 37 °C and has a doubling time of 30 min. Always use flasks that comprise at least 5x times the volume of media used, and always use lids that are able to allow air passage.

What are Bacillus spores?

Members of the species Bacillus are rod shaped, and most species are nonmotile with the exception of B. Bacillus species produce endospores that have the ability to resist heat, radiation, and chemical treatments. The external layer of the spores produced by Bacillus species, such as B. megaterium, B.

How do you find the location of spores in a smear?

The position of the spores can be seen in the smear by using endospore staining method. Endospores may be located in the middle of the bacterium ( central ), at the end of the bacterium ( terminal ), near the end of the bacteria (subterminal ), and maybe spherical or elliptical.

Why are Bacillus spores so difficult to eliminate?

Because the spores of many Bacillus species are resistant to heat, radiation, disinfectants, and desiccation, they are difficult to eliminate from medical and pharmaceutical materials and are a frequent cause of contamination. Not only they are they resistant to heat, radiation, etc., but they are also resistant to chemicals such as antibiotics.

What are the characteristics of endospores used to identify bacteria?

The size, shape, and location of endospores are particularly useful for identifying Clostridium, Bacillus, and related species. Spore formation (sporulation) occurs when nutrients, such as sources of carbon and nitrogen are depleted. Bacterial spores are highly resistant to

What is the shape and size of the spores?

Shape of the spores varies with the species and maybe oval, ellipsoidal, cylindrical or spherical. The location maybe terminal, sub-terminal or central. The spores formed are quite heat resistant and retain viability even at temperatures as high as 100°C for one minute.

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