Arthrobacter livingstonensis sp. nov. and Arthrobacter cryotolerans sp. nov., salt-tolerant and psychrotolerant species from Antarctic soil.
Two novel cold-tolerant, Gram-stain-positive, motile, facultatively anaerobic bacterial strains, LI2(T) and LI3(T), were isolated from moss-covered soil from Livingston Island, Antarctica, near the Bulgarian station St Kliment Ohridski. A rod-coccus cycle was observed for both strains. 16S rRNA gene sequence analysis revealed an affiliation to the genus Arthrobacter, with the highest similarity to Arthrobacter stackebrandtii and Arthrobacter psychrochitiniphilus for strain LI2(T) (97.8 and 97.7 % similarity to the respective type strains) and to Arthrobacter kerguelensis and Arthrobacter psychrophenolicus for strain LI3(T) (97.4 and 97.3 % similarity to the respective type strains). The growth temperature range was -6 to 28 °C for LI2(T) and -6 to 24 °C for LI3(T), with an optimum at 16 °C for both strains. Growth occurred at 0-10 % (w/v) NaCl, with optimum growth at 0-1 % (w/v) for LI2(T) and 0.5-3 % (w/v) for LI3(T). The pH range for growth was pH 4-9.5 with an optimum of pH 8 for LI2(T) and pH 6.5 for LI3(T). The predominant fatty acids were anteiso-C(15 : 0), C(18 : 0) and anteiso-C(17 : 0) for LI2(T) and anteiso-C(15 : 0) and C(18 : 0) for LI3(T). Physiological and biochemical tests clearly differentiated strain LI2(T) from A. stackebrandtii and A. psychrochitiniphilus and strain LI3(T) from A. kerguelensis and A. psychrophenolicus. Therefore, two novel species within the genus Arthrobacter are proposed: Arthrobacter livingstonensis sp. nov. (type strain LI2(T)  = DSM 22825(T)  = NCCB 100314(T)) and Arthrobacter cryotolerans sp. nov. (type strain LI3(T)  = DSM 22826(T)  = NCCB 100315(T)).
Alfred Wegener Institute for Polar and Marine Research, Research Department Potsdam, Telegrafenberg A45, 14473 Potsdam, Germany.
Lars
L
Ganzert
Alfred Wegener Institute for Polar and Marine Research, Research Department Potsdam, Telegrafenberg A45, 14473 Potsdam, Germany.
Felizitas
F
Bajerski
Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences, Section 4.3, Organic Geochemistry, Telegrafenberg B 423, 14473 Potsdam, Germany.
Kai
K
Mangelsdorf
Rheinische Friedrich-Wilhelms-Universität Bonn, Institute of Nutrition and Food Sciences, Department of Food Microbiology and Hygiene, Meckenheimer Allee 168, 53115 Bonn, Germany.
André
A
Lipski
Alfred Wegener Institute for Polar and Marine Research, Research Department Potsdam, Telegrafenberg A45, 14473 Potsdam, Germany.
Dirk
D
Wagner
D000332:Aerobiosis; D000693:Anaerobiosis; D000864:Antarctic Regions; D001173:Arthrobacter / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification* / Q000502:physiology; D016000:Cluster Analysis; D003080:Cold Temperature; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D005227:Fatty Acids / Q000032:analysis; D006863:Hydrogen-Ion Concentration; D008124:Locomotion; D008969:Molecular Sequence Data; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012965:Sodium Chloride / Q000378:metabolism; D012988:Soil Microbiology
D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D005227:Fatty Acids; D012336:RNA, Ribosomal, 16S; D012965:Sodium Chloride