'Bacillus massiliglaciei', a new bacterial species isolated from Siberian permafrost.

We describe here the main characteristics of a new species isolated from Siberian permafrost dated around 10 million years. This species was named 'Bacillus massiliglaciei' strain Marseille-P2600T (= CSUR P2600 = DSM 102861).

Microorganisms in permafrost have been much studied in recent decades [1], [2] and a large variety of bacteria, archaea, fungi and protozoa [1] were found there by using by culture-dependent and culture-independent methods [1], [3].

In February 2016, using the culturomics approach [4], a new bacterial strain named Marseille-P2600T was cultured from a Siberian permafrost sample dated around 10 million years. Growth of the strain Marseille-P2600T was obtained after 5 days in direct culture on Columbia agar (bioMérieux, Marcy l’Etoile, France) in an aerobic atmosphere at room temperature (19 ± 5°C).

On Columbia agar, these strain colonies appear grey and have a diameter of about 0.5 to 1.5 mm. The Gram staining shows Gram-positive rods. Electron microscopy reveals sticks ranging in length from 2 to 5 μm and 0.5 to 0.6 μm in diameter. Electron microscopy did not allow us to see whether spores formed. The catalase and oxidase tests were, respectively, positive and negative. Growth of the Marseille-P2600T strain occurs in aerobic and anaerobic conditions. Bacterial cells tolerate a pH of 6 to 8.5 and a NaCl concentration between 0 and 100 g/L. The 16S rRNA gene sequencing was done using universal primers FD1 and RP2 (Eurogentec, Angers, France) as previously described [5] and using a 3130-XL sequencer (Applied Biosciences, Saint Aubin, France). Marseille-P2600T showed a 97.54% sequence identity with the type strain Bacillus foraminis strain CV53 (sequence accession no. AJ717382). The phylogenetic tree of strain Marseille-P2600T showing its relationship with the closest other species is provided in Fig. 1.

FIG. 1

Phylogenetic tree showing position of ‘Bacillus massiliglaciei’ strain Marseille-P3600T relative to other phylogenetically close neighbours. Sequences were aligned using CLUSTALW, and phylogenetic inferences were obtained using maximum-likelihood method within MEGA software. Numbers at nodes are percentages of bootstrap values obtained by repeating analysis 500 times to generate majority consensus tree. Only bootstrap scores of at least 90 were retained.

Marseille-P2600T was found in Siberian permafrost and shows a 16S rRNA sequence divergence of >1.3% with its phylogenetically closest validated species [6]. Accordingly, we propose the creation of the new species ‘Bacillus massiliglaciei’ sp. nov strain Marseille-P2600T (mas.si.li′, L. masc. adj. massili, for Massilia, the old Roman name for Marseille, where the strain was isolated, and gla.ci′ei, L. gen. n. glaciei ‘of ice,’ referring to the isolation source of the strain). ‘Bacillus massiliglaciei’ sp. nov strain Marseille-P2600T is the type strain of the new species ‘Bacillus massiliglaciei.’

matrix-assisted desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) spectrum

The MALDI-TOF MS spectrum of ‘Bacillus massiliglaciei’ Marseille-P2600T is available online (http://www.mediterranee-infection.com/article.php?laref=256&titre=urms-database).

Nucleotide sequence accession number

The 16S rRNA gene sequence was deposited in GenBank under accession number LT223699.

Deposit in a culture collection

Strain Marseille-P3600T was deposited in the Collection de Souches de l’Unité des Rickettsies (CSUR, WDCM 875) under number P3600 and in the Deutsche Sammlung von Mikroorganismen und Zellkulturen under number DSM102861.