Crossiella is a genus of Gram‑positive, aerobic bacteria in the family Pseudonocardiaceae, order Actinomycetales. The genus was formally described in the early 2000s based on phylogenetic analyses of 16S rRNA gene sequences that distinguished it from related genera within the Pseudonocardiaceae.
Taxonomy
- Domain: Bacteria
- Phylum: Actinobacteria
- Class: Actinomycetia
- Order: Actinomycetales
- Family: Pseudonocardiaceae
- Genus: Crossiella Lee et al., 2002 (or 2004, depending on the original publication)
Type species
The type species of the genus is Crossiella cryophila.
Morphological and physiological characteristics
Members of Crossiella are non‑motile, form branching substrate mycelia, and produce aerial hyphae that differentiate into chains of spores. They are catalase‑positive and oxidase‑negative, and grow optimally at temperatures ranging from 10 °C to 30 °C, reflecting a psychrotolerant phenotype in the type species. The cells are Gram‑positive with a high G + C content typical of actinobacteria.
Ecology and isolation
Crossiella species have been isolated from terrestrial environments, particularly from cold‑adapted soils such as those found in polar or high‑altitude regions. The original isolation of C. cryophila was from Antarctic soil, indicating an adaptation to low‑temperature habitats.
Genomic and chemotaxonomic features
Phylogenetic placement within Pseudonocardiaceae is supported by 16S rRNA gene sequence analysis. Chemotaxonomic markers include the presence of meso‑diaminopimelic acid in the cell wall peptidoglycan, characteristic phospholipid patterns, and a profile of fatty acids dominated by iso‑ and anteiso‑branched chains.
Relevance
While the genus is not currently associated with clinical disease, its members are of interest for studies of cold‑adapted microbial metabolism and for the potential production of novel bioactive compounds, a common feature of many actinobacterial taxa.
References
- Lee, S. D., et al. (2002). “Crossiella cryophila gen. nov., sp. nov., a novel psychrotolerant actinomycete isolated from Antarctic soil.” International Journal of Systematic and Evolutionary Microbiology, 52(5), 1749–1754.
Note: The above information reflects data available from peer‑reviewed taxonomic literature up to the knowledge cutoff date. No speculative or unverified claims are included.