Two strains, designated 5413J-26T and KIS18-15T, were isolated from the air and forest soil, respectively, in South Korea. Cells of the two strains were Gram-stain-negative, aerobic, polar-flagellated and rod-shaped. According to the phylogenetic tree, strains 5413J-26T and KIS18-15T fell into the cluster of Sphingomonas sensu stricto. Strain 5413J-26T showed the highest sequence similarities with Sphingomonas trueperi LMG 2142T (96.6 %), Sphingomonas molluscorum KMM 3882T (96.5 %), Sphingomonas azotifigens NBRC 15497T (96.3 %) and Sphingomonas pituitosa EDIVT (96.1 %), while strain KIS18-15T had the highest sequence similarity with Sphingomonas soli T5-04T (96.8 %), Sphingomonas pituitosa EDIVT (96.6 %), Sphingomonas leidyi ATCC 15260T (96.6 %), Sphingomonas asaccharolytica NBRC 15499T (96.6 %) and Sphingomonas koreensis JSS26T (96.6 %). The 16S rRNA gene sequence similarity between strains 5413J-26T and KIS18-15T was 95.4 %. Ubiquinone 10 was the predominant respiratory quinone and homospermidine was the major polyamine. The major polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, and several unidentified phospholipids and lipids. The main cellular fatty acids (>10 % of the total fatty acids) of strain 5413J-26T were summed feature 8 (C18 : 1ω6c and/or C18 : 1ω7c), summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH) and C14 : 0 2-OH, and those of strain KIS18-15T were summed feature 8 and C16 : 0. Based on the results of 16S rRNA gene sequence analysis, and physiological and biochemical characterization, two novel species with the suggested names Sphingomonas aerophila sp. nov. (type strain 5413J-26T = KACC 16533T = NBRC 108942T) and Sphingomonas naasensis sp. nov. (type strain KIS18-15T = KACC 16534T = NBRC 108943T) are proposed.

A bacterial strain, ABC02-12 T , was isolated from spent mushroom compost, a waste product of button mushroom cultivation. Cells of the strain were Gram-stain-negative, catalase-and oxidasepositive, non-spore-forming, aerobic flagellated rods. Paenalcaligenes hermetiae KBL009 T . The quinone system was ubiquinone Q-8 with minor amounts of Q-7. The major fatty acids (.5 % of total fatty acids) were C 16 : 0 , C 16 : 1 v6c and/or C 16 : 1 v7c (summed feature 3), C 18 : 1 v7c and/or C 18 : 1 v6c (summed feature 8), C 17 : 0 cyclo, and iso-C 16 : 1 I, C 14 : 0 3-OH and/or an unknown fatty acid (summed feature 2). The polar lipids were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and an unknown aminolipid. Putrescine was the principal polyamine, with small amounts of 2-hydroxyputrescine and cadaverine. On the basis of the evidence presented in this study, strain T is a representative of a novel species within the genus Paenalcaligenes, for which the name Paenalcaligenes suwonensis sp. nov. is proposed. The type strain is ABC02-12 T (5KACC 16537 T 5NBRC 108927 T ).The genus Paenalcaligenes was proposed as a member of the family Alcaligenaceae belonging to the class Betaproteobacteria (Kämpfer et al., 2010). The type species of the genus, Paenalcaligenes hominis, was isolated from human blood. Later, the name Paenalcaligenes hermetiae was proposed for an isolate from the larval gut of Hermetia illucens (Lee et al., 2013). The genus was characterized as comprising Gramstain-negative, motile, short rods. Chemotaxonomically, members of the genus contained ubiquinone-8 as the predominant isoprenoid quinone and C 16 : 0 , C 17 : 0 cyclo, summed feature 2 (iso-C 16 : 1 I and/or C 14 : 0 3-OH) and summed feature 3 (C 16 : 1 v7c and/or iso-C 15 : 0 2-OH) as the major fatty acids. The polar lipids present were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, aminolipid and several polar lipids. Putrescine was the major polyamine; spermidine, spermine and cadaverine were the minor ones, and 2-hydroxyputrescine was present in trace amounts (Kämpfer et al., 2010;Lee et al., 2013).In Korea, button mushrooms (Agaricus bisporus) were cultivated on a medium mainly composed of rice straw amended with animal manure and gypsum. Spent mushroom compost, which was a waste product of button mushroom cultivation, was collected from a mushroom cultivation facility in Suwon, Republic of Korea. In the course of a study on cultivable bacteria from spent mushroom compost, one bacterial strain, designated ABC02-12 T , was isolated using a plating technique on R2A agar (BD) at 28 u C and then subjected to a taxonomic investigation using a polyphasic approach.Gram staining was determined using heat-fixed liquid cultures and the Difco Gram staining kit, according to the manufacturer's instructions. The morphology of cells and Abbreviation: AL, unknown aminolipid.