🦠microbiology review

Planctomycetes

Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025

Definition

Planctomycetes are a unique phylum of Gram-negative bacteria characterized by their unusual cell biology, including the presence of membrane-bound compartments within their cells. They are found in various aquatic environments and play roles in nitrogen and carbon cycles.

5 Must Know Facts For Your Next Test

  1. Planctomycetes possess intracellular compartmentalization similar to eukaryotic cells, which is rare among prokaryotes.
  2. They participate in the global nitrogen cycle through processes such as anammox (anaerobic ammonium oxidation).
  3. Planctomycetes lack peptidoglycan in their cell walls, which is atypical for bacteria.
  4. Members of this phylum can be found in diverse environments, including freshwater, marine habitats, and soil.
  5. Gemmata obscuriglobus is a well-known species within Planctomycetes and is notable for its complex internal membrane system.

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