Larkinella humicola sp. nov., a gamma radiation-resistant bacterium isolated from soil.

A Gram-negative, short rod-shaped, and pink-pigmented bacterial strain, designated MA1T, was isolated from a soil sample from Gijang-gun, Busan in Republic of Korea. The 16S rRNA gene sequence analysis showed that strain MA1T belonged to the genus Larkinella and was closely related to "Larkinella punicea" (97.5% similarity), Larkinella rosea 15J16-1T3AT (96.5%), and Larkinella knui 15J6-3T6T (96.2%). Polar lipid profile of strain MA1T contained phosphatidylethanolamine, two unidentified aminolipids, and three unidentified lipids. Menaquinone-7 was the only quinone and the main fatty acids were C16:1 ω5c (36.7%), iso-C15:0 (30.0%), iso-C17:0 3-OH (7.7%), and summed feature 3 (C16:1 ω6c and/or C16:1 ω7c and/or iso-C15:0 2-OH) (7.3%). The genomic DNA G + C content was 52.3 mol% based on the whole-genome analysis. Strain MA1T exhibited a relatively low level of ANI and in silico DDH values with "Larkinella punicea" (91.9 and 47.1%, respectively), Larkinella rosea (79.7 and 23.3%), and Larkinella knui (81.9 and 25.7%). Based on its phenotypic properties and phylogenetic distinctiveness, strain MA1T should be classified in the genus Larkinella as a representative of a novel species, for which the name Larkinella humicola sp. nov. is proposed. The type strain is MA1T (= KCTC 72629T = NBRC 114191T).

Larkinella punicea sp. nov., isolated from manganese mine soil.

Strain ZZJ9T is a Gram-stain-negative, rod-shaped, aerobic bacterium isolated from manganese mine soil. Strain ZZJ9T showed the highest 16S rRNA gene sequence similarities with Larkinella rosea 15J16-1T3AT (97.1%), Larkinella terrae 15J8-8T (97.0%), Larkinella knui 15J6-3T6T (96.8%), and Larkinella ripae 15J11-1T (95.3%). The genome size of strain ZZJ9T was 8.01 Mb and the DNA G+C content was 51.8 mol%. ANI values among strain ZZJ9T and Larkinella rosea 52004 T, Larkinella knui KCTC 42998T, and Larkinella terrae 52001T were 80.5%, 82.7%, and 80.5%, respectively. dDDH values among strain ZZJ9T and Larkinella rosea 52004T, Larkinella knui KCTC 42998T, and Larkinella terrae 52001T were 23.5%, 26.0%, and 23.6%, respectively. Furthermore, the genome of strain ZZJ9T contained 6302 predicted protein-coding genes and 3114 (49%) of them had classificatory functions. The major quinone of strain ZZJ9T was menaquinone-7 and the main cellular fatty acids were C16:1ω5c (39.5%), iso-C15:0 (25.6%), and iso-C17:0 3OH (11.5%). The polar lipids of strain ZZJ9T were phosphatidylethanolamine, unidentified lipid, and two unidentified aminolipids. Based on the results of phylogenetic, genome, phenotypic, and chemotaxonomic analytical, strain ZZJ9T represents a novel species of the genus Larkinella, for which the name Larkinella punicea sp. Nov. is proposed. The type strain is ZZJ9T (= KCTC 62876T = CCTCC AB 2018215T).

Larkinella knui sp. nov., isolated from soil.

A Gram-stain-negative, motile by gliding, rod-shaped, aerobic bacterium, designated 15J6-3T6T, was isolated from a soil sample collected from Jeju Island, South Korea, and characterized taxonomically using a polyphasic approach. Comparative 16S rRNA gene sequence analysis showed that strain 15J6-3T6T belongs to the family Cytophagaceae and is related to Larkinella harenae 15J9-9T (93.9 % similarity), Larkinella arboricola Z0532T (93.6 %), Larkinella bovis M2TB15T (93.3 %), and Larkinella insperata LMG 22510T (93.3 %). The DNA G+C content of strain 15J6-3T6T was 50.6 mol%. The detection of phosphatidylethanolamine and an unidentified polar lipid as major polar lipids, menaquinone-7 as the predominant quinone, and C16 : 1ω5c, iso-C15 : 0, and iso-C17 : 0 3-OH as the major fatty acids also supports the affiliation of the isolate to the genus Larkinella. Based on its phenotypic properties and phylogenetic distinctiveness, we propose that strain 15J6-3T6T should be classified in the genus Larkinella as a representative of a novel species, for which the name Larkinella knui sp. nov. is proposed. The type strain is 15J6-3T6T (=KCTC 42998T=JCM 31989T).

Larkinella terrae sp. nov., isolated from soil on Jeju Island, South Korea.

A Gram-stain negative, non-motile, rod-shaped, aerobic bacterium, designated 15J8-8T, was isolated from a soil sample collected on Jeju Island, South Korea, and characterized taxonomically using a polyphasic approach. Comparative 16S rRNA gene sequence analysis showed that strain 15J8-8T belongs to the family Cytophagaceae and is related to Larkinella bovis M2TB15T (95.0%), 'Larkinella harenae' 15J9-9 (94.5%), Larkinella arboricola Z0532T (93.2%), and Larkinella insperata LMG 22510T (93.0%). The DNA G+C content of strain 15J8-8T was 50.5 mol%. The detection of phosphatidylethanolamine and two unidentified polar lipids as major polar lipids; menaquinone-7 as the predominant quinone; and C16:1 ω5c, C16:0 N alcohol, and iso-C15:0 as the major fatty acids also supported the affiliation of the isolate to the genus Larkinella. Based on its phenotypic properties and phylogenetic distinctiveness, strain 15J8-8T should be classified in the genus Larkinella as representative of a novel species, for which the name Larkinella terrae sp. nov. is proposed. The type strain is 15J8-8T (= KCTC 52001T = JCM 31990T).

Larkinella soli sp. nov., isolated from biological soil crusts.

A novel bacterial strain, designated MIMbqt9T, was isolated from biological soil crusts collected in Erdos Plateau in Inner Mongolia. Cells were light pink, rod-shaped, aerobic, Gram-reaction-negative, motile by gliding, oxidase- and catalase-positive. Cell growth could be observed at 5-40 °C (optimum at 30 °C), at pH 4.0-6.0 (optimum at 6.0) and with 1 % (w/v) NaCl. Phylogenetic analysis of 16S rRNA gene sequence showed that strain MIMbqt9T was most closely related to the members of genus Larkinella, including L. bovis M2T2B15T (92.06 %), L. arboricola Z0532T (92.00 %) and L. insperata LMG 22510T (91.94 %). The major cellular fatty acids of strain MIMbqt9T were C16 : 1ω5c, iso-C15 : 0 and iso-C17 : 0 3-OH. Polar lipids of the strain MIMbqt9T were mainly composed of phosphatidylethanolamine (PE), phosphatidylserine (PS), two unidentified aminolipids (AL1 and AL2) and two unidentified phospholipids (PL1 and PL2). Menaquinone 7 (MK-7) was the major respiratory quinone. The G+C content of the chromosomal DNA was 57.63 mol%. On the basis of morphology, physiology, fatty acid composition, phylogeny and 16S rRNA gene sequence analysis, the isolates are assigned to a novel species of the genus Larkinella, for which the name Larkinella soli sp. nov. is proposed. The type strain is MIMbqt9T (=MCCC 1K01309T=KCTC 42800T).

Larkinella ripae sp. nov., isolated from seashore soil.

Strain 15J11-11T was isolated from soil collected at the seashore and was Gram-staining-negative, short-rod-shaped, gliding and pale-pink pigmented. Flexirubin-type pigments were absent. The isolate grew at a temperature range of 15 to 30 °C and a pH range of 7 to 8. Comparative 16S rRNA gene sequence studies showed that strain 15J11-11T belonged to the genus Larkinella within the phylum Bacteroidetes and was most closely related to Larkinella arboricola Z0532T (95.6 %), Larkinella bovis M2TB15T (95.4 %), and Larkinella insperata LMG 22510T (95.2 %). The genomic DNA G+C content of strain 15J11-11T was 53.2 mol%. The strain contained phosphatidylethanolamine, phosphatidylserine, an unidentified aminophospholipid and two unidentified polar lipids as the major polar lipids; menaquinone-7 as the predominant quinone and C16 : 1ω5c, iso-C15 : 0 and iso-C17 : 0 3-OH as the major fatty acids which supported the affiliation of strain 15J11-11T to the genus Larkinella. Based on its phenotypic properties and phylogenetic distinctiveness, strain 15J11-11T represents a novel species of the genus Larkinella, for which the name Larkinella ripae sp. nov. is proposed. The type strain is 15J11-11T (=KCTC 42996T=JCM 31657T).

Larkinella roseus sp. nov., a species of the family Cytophagaceae isolated from beach soil.

The taxonomic position of bacterial strain, designated 15J16-1T3AT, recovered from a soil sample was established using a polyphasic approach. Phylogenic analysis based on the 16S rRNA gene sequence showed that strain 15J16-1T3AT belonged to the family Cytophagaceae, phylum Bacteroidetes, and was most closely related to 'Larkinella harenae' 15J9-9 (95.9% similarity), Larkinella ripae 15J11-11T (95.6%), Larkinella bovis M2TB15T (94.7%), Larkinella arboricola Z0532T (93.9%), and Larkinella insperata LMG 22510T (93.5%). Cells were rod-shaped, Gram-stain-negative, aerobic, and nonmotile. The isolate grew on NA, R2A, TSA, but not on LB agar. The strain was able to grow at temperature range from 10°C to 30°C with an optimum at 25°C and pH 6-8. Menaquinone MK-7 was the predominant respiratory quinone. The major cellular fatty acids comprised C16:1ω5c (48.6%) and C15:0 iso (24.1%). Phosphatidylethanolamine, phosphatidylserine, and an unidentified lipid were the major polar lipids. The G + C content of the genomic DNA was 49.5 mol%. Strain 15J16-1T3AT could be distinguished from its closest phylogenetic neighbors based on its phenotypic, genotypic, and chemotaxonomic features. Therefore, the isolate is considered to represent a novel species in the genus Larkinella, for which the name Larkinella roseus sp. nov. is proposed. The type strain is 15J16-1T3AT (= KCTC 52004T = JCM 31991T).