Salicibibacter cibarius sp. nov. and Salicibibacter cibi sp. nov., two novel species of the family Bacillaceae isolated from kimchi

• Published in: The journal of microbiology Vol. 59; no. 5; pp. 460 - 466
• Main Authors: Oh, Young Joon, Kim, Joon Yong, Lim, Seul Ki, Kwon, Min-Sung, Choi, Hak-Jong
• Format: Journal Article
• Language: English
• Published: Seoul The Microbiological Society of Korea 01-05-2021; Springer Nature B.V; 한국미생물학회
• Subjects: Biomedical and Life Sciences; Cardiolipin; Catalase; Fatty acids; Genomes; Genomics; Kimchi; Life Sciences; Lipids; Menaquinones; Microbial Systematics and Evolutionary Microbiology; Microbiology; New species; Phosphatidylglycerol; Phospholipids; Phylogeny; rRNA 16S; Similarity; Sodium chloride; Species; 생물학; kimchi; halophilic bacterium; taxonomy; Salicibibacter cibi; Salicibibacter cibarius
• ISSN: 1225-8873; 1976-3794
• DOI: 10.1007/s12275-021-0513-1

To date, all species in the genus
Salicibibacter
have been isolated in Korean commercial kimchi. We aimed to describe the taxonomic characteristics of two strains, NKC5-3
T
and NKC21-4
T
, isolated from commercial kimchi collected from various regions in the Republic of Korea. Cells of these strains were rod-shaped, Gram-positive, aerobic, oxidase- and catalase-positive, non-motile, halophilic, and alkalitolerant. Both strains, unlike other species of the genus
Salicibibacter
, could not grow without NaCl. Strains NKC5-3
T
and NKC21-4
T
could tolerate up to 25.0% (w/v) NaCl (optimum 10%) and grow at pH 7.0–10.0 (optimum 8.5) and 8.0–9.0 (optimum 8.5), respectively; they showed 97.1% 16S rRNA gene sequence similarity to each other and were most closely related to
S. kimchii
NKC1-1
T
(97.0% and 96.8% similarity, respectively). The genome of strain NKC5-3
T
was nearly 4.6 Mb in size, with 4,456 protein-coding sequences (CDSs), whereas NKC21-4
T
genome was nearly 3.9 Mb in size, with 3,717 CDSs. OrthoANI values between the novel strains and
S. kimchii
NKC1-1
T
were far lower than the species demarcation threshold. NKC5-3
T
and NKC21-4
T
clustered together to form branches that were distinct from the other
Salicibibacter
species. The major fatty acids in these strains were anteiso-C
15:0
and anteiso-C
17:0
, and the predominant menaquinone was menaquinone-7. The polar lipids of NKC5-3
T
included diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), and five unidentified phospholipids (PL), and those of NKC21-4
T
included DPG, PG, seven unidentified PLs, and an unidentified lipid. Both isolates had DPG, which is the first case in the genus
Salicibibacter
. The genomic G + C content of strains NKC5-3
T
and NKC21-4
T
was 44.7 and 44.9 mol%, respectively. Based on phenotypic, genomic, phylogenetic, and chemotaxonomic analyses, strains NKC5-3
T
(= KACC 22040
T
= DSM 111417
T
) and NKC21-4
T
(= KACC 22041
T
= DSM 111418
T
) represent two novel species of the genus
Salicibibacter
, for which the names
Salicibibacter cibarius
sp. nov. and
Salicibibacter cibi
sp. nov. are proposed.