Description of Actinomycetospora chibensis sp. nov., Actinomycetospora chlora sp. nov., Actinomycetospora cinnamomea sp. nov., Actinomycetospora corticicola sp. nov., Actinomycetospora lutea sp. nov., Actinomycetospora straminea sp. nov. and Actinomycetospora succinea sp. nov. and emended description of the genus Actinomycetospora

Abstract

Eight actinomycete strains that form bud-like spore chains were isolated from various samples collected in Japan. Phylogenetically, the isolates formed a single clade with the type strain of Actinomycetospora chiangmaiensis according to 16S rRNA gene sequence analysis. The isolates contained meso-diaminopimelic acid, d-glutamic acid and d- and l- alanine in the cell-wall peptidoglycan, arabinose and galactose as characteristic sugars, phosphatidylcholine and phosphatidylethanolamine as diagnostic phospholipids, MK-8(H4) as the predominant isoprenoid quinone, iso-C16 : 0 as the major cellular fatty acid and DNA G+C contents of 72–74 mol%. Actinomycetospora chiangmaiensis, the type species of the genus Actinomycetospora, was also found to contain MK-8(H4) predominantly in our study, although it was earlier reported to contain MK-9(H4) as the predominant isoprenoid quinone. On the basis of the morphological, physiological, chemotaxonomic, phylogenetic and DNA–DNA hybridization data, we concluded that the isolates can be accommodated in the genus Actinomycetospora with emendation of the description of the genus and are assigned to the following seven novel species: Actinomycetospora chibensis sp. nov. (type strain TT04-21T  = NBRC 103694T  = KACC 14256T), Actinomycetospora chlora sp. nov. (type strain TT07I-57T  = NBRC 105900T  = KACC 14252T), Actinomycetospora cinnamomea sp. nov. (type strain IY07-53T  = NBRC 105527T  = KACC 14250T), Actinomycetospora corticicola sp. nov. (type strain 014-5T  = NBRC 103689T  = KACC 14253T), Actinomycetospora lutea sp. nov. (type strain TT00-04T  = NBRC 103690T  = KACC 14254T), Actinomycetospora straminea sp. nov. (type strain IY07-55T  = NBRC 105528T  = KACC 14251T) and Actinomycetospora succinea sp. nov. (type strain TT00-49T  = NBRC 103691T  = KACC 14255T).