RT Journal Article SR Electronic(1) A1 Lee, Yunho A1 Jeon, Che OkYR 2018 T1 Methylobacterium frigidaeris sp. nov., isolated from an air conditioning system JF International Journal of Systematic and Evolutionary Microbiology, VO 68 IS 1 SP 299 OP 304 DO https://doi.org/10.1099/ijsem.0.002500 PB Microbiology Society, SN 1466-5034, AB A reddish pink-pigmented, Gram-stain-negative, aerobic and methylotrophic bacterial strain, designated strain IER25-16T, was isolated from a laboratory air conditioning system in the Republic of Korea. Cells were motile rods showing catalase- and oxidase-positive reactions. Strain IER25-16T grew at 10–40 °C (optimum, 30 °C), at pH 4.0–7.0 (optimum, pH 5.0–7.0) and in the presence of 0–1.0 % (w/v) NaCl (optimum, 0 %). The major respiratory quinone was ubiquinone-10 and ubiquinone-9 was also detected as the minor respiratory quinone. Summed feature 8 (comprising C18 : 1 ω7c and/or C18 : 1 ω6c) was detected as the predominant fatty acids. The genomic DNA G+C content of strain IER25-16T was 70.0 mol%. Phylogenetic analysis based on 16S rRNA gene sequence comparison revealed that strain IER25-16T belonged to the genus Methylobacterium of the class Alphaproteobacteria . Strain IER25-16T was most closely related to Methylobacterium platani PMB02T (97.9 %), Methylobacterium aquaticum GR16T (97.9 %) and Methylobacterium tarhaniae N4211T (97.5 %). The average nucleotide identity and in silico DNA–DNA hybridization values between strain IER25-16T and M. platani , M. aquaticum and M. tarhaniae were 88.3, 88.8 and 89.6 % and 36.2, 37.3 and 39.3 %, respectively. The phenotypic and chemotaxonomic features and the phylogenetic inference clearly suggested that strain IER25-16T represents a novel species of the genus Methylobacterium , for which the name Methylobacterium frigidaeris sp. nov. is proposed. The type strain is strain IER25-16T (=KACC 19280T=JCM 32048T)., UL https://www.microbiologyresearch.org/content/journal/ijsem/10.1099/ijsem.0.002500