In the year 2002, Bifidobacterium longum, Bifidobacterium infantis and Bifidobacterium suis were unified into a single species, Bifidobacterium longum, preserving the former species names through the creation of the three biotypes ‘longum’, ‘infantis’ and ‘suis’. Consequently, the use of the species names B. infantis and B. suis was to be discontinued. The above taxonomic rearrangement of B. longum was based on DNA–DNA hybridizations and 16S rRNA and HSP60 gene sequence analysis. However, a variety of other genotypic techniques including ribotyping, amplified rDNA restriction analysis (ARDRA), randomly amplified polymorphic DNA (RAPD)-PCR, BOX-PCR, PCR-denaturing gradient gel electrophoresis (DGGE), comparison of the recA, tuf and ldh gene sequences, plasmid profiling and considerable variation in carbohydrate fermentation patterns as well as results of starch and PAGE electrophoresis experiments clearly discriminate former B. longum, B. infantis and B. suis strains. In the present paper we compile this published information and propose the description of Bifidobacterium longum subsp. longum subsp. nov., Bifidobacterium longum subsp. infantis comb. nov. and Bifidobacterium longum subsp. suis comb. nov. The International Committee on Systematics of Prokaryotes Subcommittee on the taxonomy of Bifidobacterium, Lactobacillus and related organisms is in favour of this proposal. The type strains of Bifidobacterium longum subsp. longum subsp. nov., subsp. infantis comb. nov. and subsp. suis comb. nov. are E194b (variant a)T (ATCC 15707T=DSM 20219T), S12T (=ATCC 15697T=DSM 20088T) and Su859T (ATCC 27533T=DSM 20211T), respectively.
A novel actinobacterium, designated strain SST-39T, was isolated from a marine sediment sample collected in Jeju, Republic of Korea. Cells were facultatively anaerobic, Gram-positive, non-endospore-forming, non-motile rods. Colonies were circular, slightly convex, opaque and brilliant yellow. The cell-wall peptidoglycan of the organism contained ll-diaminopimelic acid as the diagnostic diamino acid. Polar lipids included phosphatidylglycerol and diphosphatidylglycerol. The predominant menaquinone was MK-9(H4). The major cellular fatty acids were anteiso-C15 : 0, C18 : 0 and C16 : 0. The DNA G+C content was 68.4 mol%. A phylogenetic tree based on 16S rRNA gene sequences indicated that the isolate belonged to the family Propionibacteriaceae and formed a unique cluster with the type strain of Tessaracoccus bendigoensis (97.0 % sequence similarity). Other phylogenetic neighbours were the type strains of Luteococcus peritonei (95.1 % 16S rRNA gene sequence similarity) and Propionibacterium propionicum (95.1 %). On the basis of its phenotypic and phylogenetic distinctiveness, strain SST-39T is considered to represent a novel species of the genus Tessaracoccus, for which the name Tessaracoccus flavescens sp. nov. is proposed. The type strain is SST-39T (=DSM 18582T =KCTC 19196T).
A Gram-positive, cream-coloured, non-motile, rod-shaped actinomycete, designated DLS-10T, was isolated from a rock collected on the peak of Darangshi Oreum (a small mountain 300 m above sea level) in Jeju, Republic of Korea. The temperature and pH ranges for growth were 4–37 °C and pH 5.1–9.1. The organism grew at NaCl concentrations up to 3 % and had the following chemotaxonomic characteristics: meso-diaminopimelic acid was the diagnostic diamino acid in the cell-wall peptidoglycan, the polar lipids included diphosphatidylglycerol, phosphatidylmethylethanolamine and two unknown phospholipids, the major menaquinone was MK-8(H4) and the major fatty acids were anteiso-C15 : 0, C16 : 0, iso-C16 : 0 and anteiso-C17 : 0. The DNA G+C content was 74.3 mol%. Phylogenetic analyses based on 16S rRNA gene sequences revealed that the organism was related to members of the family Nakamurellaceae in the suborder Frankineae. The most closely related described organisms were the type strains of Humicoccus flavidus (97.1 % sequence similarity) and Nakamurella multipartita (95.2 %). On the basis of the morphological, cultural, physiological, chemotaxonomic and phylogenetic evidence presented here, the organism represents a novel genus and species of the family Nakamurellaceae, for which the name Saxeibacter lacteus gen. nov., sp. nov. is proposed. The type strain of Saxeibacter lacteus is DLS-10T (=KCTC 19285T =DSM 19367T).
Three actinomycete strains, MC5-1T, MC7-1 and R1-1, were isolated from soil samples collected in Thailand. Their taxonomic positions were determined using a polyphasic approach. The chemotaxonomic characteristics of these strains coincided with those of the genus Micromonospora, i.e. meso-diaminopimelic acid and N-glycolyl muramic acid were present in the cell-wall peptidoglycan, the whole-cell sugars were of pattern D, the phospholipids were of type II and the cellular fatty acids were of type 3b. Phylogenetic analysis of the 16S rRNA gene sequences revealed a close relationship between strains MC5-1T, MC7-1 and R1-1 (99.8 % sequence similarity) and Micromonospora auratinigra JCM 12357T (99.3 %). The three novel strains were clearly distinguishable from M. auratinigra JCM 12357T from the low DNA–DNA relatedness (≤43.4 %). On the basis of the data presented, strain MC5-1T represents a novel species of the genus Micromonospora, for which the name Micromonospora chaiyaphumensis is proposed. The type strain is MC5-1T (=KCTC 19332T=JCM 12873T=PCU 267T=TISTR 1564T).
A novel actinomycete strain, designated HSW-1T, was isolated from seawater collected from Hwasun Beach on the coast of Jeju Island, Republic of Korea. The cells were aerobic, Gram-positive, oxidase-negative, catalase-positive, non-motile rods. The colonies were circular, smooth, convex and yellow in colour. The cell-wall peptidoglycan of this organism contained ll-diaminopimelic acid as the diagnostic diamino acid. The polar lipids included phosphatidylinositol, diphosphatidylglycerol, phosphatidylglycerol and three unknown phospholipids. The predominant menaquinone was MK-9(H4). The major fatty acids were C18 : 1 ω9c, C16 : 0, C16 : 0 2-OH and 10-methyl C18 : 0. The DNA G+C content was 74.0 mol%. A neighbour-joining tree based on 16S rRNA gene sequences showed that this organism falls within the radiation of the genus Aeromicrobium. The closest phylogenetic neighbours were the type strains of Aeromicrobium erythreum (98.2 % 16S rRNA gene sequence similarity), Aeromicrobium alkaliterrae (97.9 %), Aeromicrobium marinum (97.3 %) and Aeromicrobium fastidiosum (97.0 %). The DNA–DNA relatedness values between the novel isolate and its closest relative, A. erythreum DSM 8599T, ranged between 32 and 36 %. On the basis of the phenotypic and DNA–DNA hybridization data, strain HSW-1T represents a novel species of the genus Aeromicrobium, for which the name Aeromicrobium ponti sp. nov. is proposed. The type strain is HSW-1T (=DSM 19178T=KACC 20565T).
A bacterial strain isolated from sewage sludge compost, strain SC-083T, was characterized. The isolate was a motile, Gram-positive, short rod, forming coryneform V-shaped cells during the early stages of growth. The organism was strictly aerobic and able to grow between 22 and 36 °C and between pH 5.5 and 8.0. The predominant fatty acids were cyclohexyl-C17 : 0, anteiso-C17 : 0 and iso-C16 : 0, the major respiratory quinones were menaquinone 11 (MK-11) and 12 (MK-12), and the genomic DNA G+C content was 68 mol%. The peptidoglycan contained the diagnostic diamino acids ornithine and 2,4-diaminobutyric acid and was of acetyl type. The 16S rRNA gene sequence analysis indicated that this isolate belongs to the family Microbacteriaceae with the type strains of the species Leifsonia xyli (96 % gene sequence similarity), Leifsonia shinshuensis (96 %), Leifsonia naganoensis (95 %), Leifsonia aquatica (95 %), Agromyces ramosus (95 %) and Curtobacterium citreum (95 %) among the closest phylogenetic neighbours. The phylogenetic analysis and phenetic characteristics support the proposal of a new genus and a novel species, with the name Humibacter albus gen. nov., sp. nov. The type strain of Humibacter albus is SC-083T (=DSM 18994T =CCUG 54538T =LMG 23996T).
Strain KV-677T, a Gram-positive, aerobic, motile, rod-shaped bacterium, was isolated from park soil in Tokyo, Japan, and characterized. It grew well at 15–30 °C on nutrient agar and colonies were pale yellow. The cell-wall peptidoglycan contained diaminobutyric acid, glycine, alanine and glutamic acid and the muramic acid acyl type was acetyl. The predominant menaquinone was MK-12. Mycolic acids were not detected. The DNA G+C content was 70 mol%. 16S rRNA gene sequence analysis revealed that strain KV-677T fell within the cluster of the family Microbacteriaceae and formed a separate lineage joining the genera Salinibacterium, Rhodoglobus, Subtercola and Agreia, showing 95.5–96.9 % sequence similarities with the type strains of the type species of the above genera. However, strain KV-677T clearly differed from these and other genera with relatively high sequence similarity in its chemotaxonomic characteristics. Therefore, it is proposed that strain KV-677T represents a novel species in a new genus, Microterricola viridarii gen. nov., sp. nov., in the family Microbacteriaceae. The type strain of Microterricola viridarii is KV-677T (=NRRL B-24538T =NBRC 102123T).
Streptomyces griseus strain 45H, isolated in 1960 during a mutagenesis programme on the industrial streptomycin producer S. griseus 52-1, encodes an extracellular, pleiotropic autoregulatory signalling protein, factor C, which stimulates sporulation of S. griseus 52-1 in submerged culture. The facC gene, which codes for factor C, is present in very few streptomycetes and is not present in S. griseus 52-1. Based on 16S rRNA gene sequencing and other molecular data, S. griseus 45H, the factor C producer, is here shown to be related to the original laboratory strain of Streptomyces flavofungini, which was being studied in the same laboratory in 1960, and to Streptomyces albidoflavus. Southern blotting revealed that three out of four independently isolated strains of S. albidoflavus possess facC. Both the original strain of S. flavofungini and S. griseus 45H are therefore identified as members of the species Streptomyces albidoflavus, and we propose that S. griseus 45H should be renamed Streptomyces albidoflavus 45H.