Validation of Mesorhizobium maamorense sp. nov., a novel rhizobial species isolated from Ononis repens.
Submitted by alami, soufiane
Abstract
Mesorhizobium maamorense sp. nov. is a novel rhizobial species isolated from Ononis repens nodules in Morocco. The type strain, ORM16ᵀ (= DSM 116631ᵀ = CCMM B1359ᵀ), is phylogenetically related to M. opportunistum but clearly distinct based on MLSA and whole-genome analysis (ANI 87.63%, dDDH 31.2%). This Gram-negative, aerobic rod-shaped bacterium possesses canonical nod genes and shows moderate stress tolerance. The species name refers to the Maâmora forest, its site of origin.
Species Mesorhizobium maamorense
- Etymology
- [ma.a.mo.ren'se] N.L. neut. adj. maamorense, pertaining to the Maamora forest, the region of isolation
- Nomenclatural type
- NCBI Assembly: GCA_044998965.1 Ts
- Reference Strain
- Strain sc|0040742: ORM16 = DSM 120599 = CCMM B1359 (Cat. )
- Description
-
The species is an aerobic, non-spore-forming, Gram-negative rhizobium that appears as an elongated rod, approximately 1 µm wide and 2.5 µm long. On YEM medium, it grows relatively quickly, with a population doubling time of 5 to 6 hours, forming 1 mm colonies within five days. Ideal growth conditions are a temperature of 28°C and a neutral pH of 7, though it remains viable at temperatures as high as 37°C. The bacteria is also resilient to environmental challenges, tolerating saline stress equivalent to 515 mM NaCl and osmotic stress from up to 20% PEG.
- Classification
- Bacteria » Pseudomonadota » Alphaproteobacteria » Hyphomicrobiales » Phyllobacteriaceae » Mesorhizobium » Mesorhizobium maamorense
- References
-
Effective publication:
Alami et al., 2026 [1]
Assigned taxonomically: Laadraoui et al., 2023 [2] - Registry URL
- https://seqco.de/i:51228
References
- Alami et al. (2026). Mesorhizobium maamorense sp. nov., a novel symbiotic nitrogen-fixing bacterium isolated from nodules of Ononis repens in the Moroccan Maâmora forest. Antonie van Leeuwenhoek. DOI:10.1007/s10482-026-02251-8
- Laadraoui et al. (2023). Identification of the symbiovar maamori in Mesorhizobium isolated from nodules of Ononis repens in the Maamora forest (Morocco). Symbiosis. DOI:10.1007/s13199-022-00890-9
Register List Certificate of Validation
On behalf of the Committee on the Systematics of Prokaryotes Described from Sequence Data (SeqCode Committee), we hereby certify that the Register List seqco.de/r:-bmttyad submitted by alami, soufiane and including 1 new name has been successfully validated.
Date of Priority:
2026-01-15 07:09 UTC
DOI: 10.57973/seqcode.r:-bmttyad