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Bacteria produce a single endospore internally. The spore is sometimes surrounded by a thin covering known as the exosporium, which overlies the spore coat. The spore coat, which acts like a sieve that excludes large toxic molecules like lysozyme, is resistant to many toxic molecules and may also contain enzymes that are involved in germination.
Spores form part of the life cycles of many plants, algae, fungi and protozoa. [2] They were thought to have appeared as early as the mid-late Ordovician period as an adaptation of early land plants. [3] Bacterial spores are not part of a sexual cycle, but are resistant structures used for survival under unfavourable conditions. [4]
The wrong decision can be catastrophic: a vegetative cell will die if the conditions are too harsh, while bacteria forming spores in an environment which is conducive to vegetative growth will be out competed. [3] In short, initiation of sporulation is a very tightly regulated network with numerous checkpoints for efficient control. [citation ...
Bacillus subtilis spores can survive the extreme heat generated during cooking. Some B. subtilis strains are responsible for causing ropiness or rope spoilage – a sticky, stringy consistency caused by bacterial production of long-chain polysaccharides – in spoiled bread dough and baked goods. [74]
This technique resulted in major advances in genetic transformation of C. perfringens, due to the bacteria often displaying itself as a vegetative cell or as dormant spores in food. [23] The electric pulse creates pores in the bacterial cell membrane and allows the passive influx of DNA molecules. [24]
Endospore stain on Bacillus subtilis.The spore is stained green and the vegetative cell is stained a pinkish red color. Endospore staining is a technique used in bacteriology to identify the presence of endospores in a bacterial sample. [1]
Resident spores in the soil are swallowed by grubs during their normal pattern of feeding on roots. This ingestion of the spore by the host activates reproduction of the bacteria inside the grub. Within 7–21 days the grub will eventually die and as the grub decomposes, billions of new spores are released into the soil.
Some bacteria also produce endospores with an exosporium, of which the most commonly studied are Bacillus species, particularly Bacillus cereus and the anthrax-causing bacterium Bacillus anthracis. The exosporium is the portion of the spore that interacts with the environment or host organism, and may contain spore antigens. [1]