Myxospores

Abstract

Myxospores are spores produced by the myxobacteria, a subset of gliding bacteria that aggregate to form multicellular structures that contain the differentiated spores.

Keywords: starvation; cell–cell signalling; spore; differentiation; multicellular development; fruiting body; aggregation

Figure 1.

The life cycle of the myxobacterium, Myxococcus xanthus. If nutrients are available, M. xanthus cells grow vegetatively (left panel). If starved for nutrients, the developmental programme is activated (right panel) and key events, such as rippling and mound formation, follow a temporal programme involving the expression of new genes. If nutrients become available, spores within the fruiting body germinate into rod‐shaped vegetative cells (bottom half of right panel).

Figure 2.

Spore‐filled fruiting bodies on starvation agar. These 1‐week‐old fruiting bodies measure up to 0.7 mm in height and are filled with refractile spores. (a) Myxobacterium isolated from rabbit dung in Moscow, Idaho. (b) Myxococcus xanthus.

Figure 3.

Myxospores harvested from a fruiting body. (a) Refractile, heat‐resistant spores of Myxococcus xanthus. (b) Rod‐shaped cells within the fruiting body that have not formed spores. (c) Nonrefractile, heat‐sensitive spores.

Figure 4.

Transmission electron micrographs of Myxococcus xanthus. (a) Vegetative rod‐shaped cell. (b) A developing spore, 35 hours after starvation. (c) A developing spore, 40 hours after starvation. (d) A mature spore at 4 weeks. (e) A germinating cell, 7 hours after addition of nutrients. Photographs were provided by Dr Martin Dworkin, reprinted from (Voelz and Dworkin, ) with the permission of the American Society for Microbiology.

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References

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How to Cite close
Hartzell, Patricia L, and White, David J(Dec 2001) Myxospores. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1038/npg.els.0000307]