Numerical and chemical classification of Actinoplanes and some related actinomycetes

Abstract

Sixty-eight Actinoplanes isolates from freshwater sediments were compared through 89 unit characters with marker strains of the genera Actinoplanes, Ampullariella, Dactylosporangium, Micromonospora, Planobispora, Spirillospora and Streptosprangium. The data were examined using the simple matching, Jaccard and pattern coefficients and clustering was achieved using the unweighted pair group method with arithmetic averages algorithm. The numerical classification was only marginally affected by the statistics used or by test error, estimated at 5%. Most of the environmental isolates were recovered in five major clusters that were equated with taxospecies. Seven major, nine minor and 29 single-member clusters defined by the SSM coefficient at the 83% similarity (S-) level, were assigned to two aggregate groups circumscribed at the 68% S-level. The first cluster group was composed of strains belonging to the genera Actinoplanes (including Ampullariella), Dactylosporangium and Micromonospora and the second included representatives of the genera Planobispora, Planomonospora, Spirillospora and Streptosporangium. Selected Actinoplanes strains subjected to chemical analyses contained complex mixtures of straight-and branched-chain fatty acids, tetrahydrogenated menaquinones with nine isoprene units as the predominant isoprenologue, and major amounts of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylinositol; the representative environmental isolates were also shown to contain meso-and hydroxydiaminopimelic acid; the principal wall sugars were arabinose, galactose, glucose, mannose and xylose. The chemical and numerical taxonomic data support the integrity of established species of Actinoplanes, with the exception of Actinoplanes caeruleus, and show that the five major clusters encompassing environmental isolates merit the rank of species. It is proposed that the five novel taxa be assigned to the genus Actinoplanes as Actinoplanes consettensis sp. nov., Actinoplanes derwentensis sp. nov., Actinoplanes durhamensis sp. nov., Actinoplanes humidus sp. nov., and Actinoplanes palleronii sp. nov. Similarly, the genera Actinoplanes, Dactylosporangium, Micromonospora and Pilimelia have many properties in common and it is proposed that they be classified in the family Micromonosporaceae Krassilnikov 1938; an emended description of this taxon is given. The family Streptosporangiaceae fam. nov. is proposed to accommodate organisms assigned to the genera Microbispora, Microtetraspora, Planobispora, Planomonospora and Streptosporangium.

Phylogenetic analysis of the genus Actinoplanes and transfer of Actinoplanes minutisporangius Ruan et al. 1986 and 'Actinoplanes aurantiacus' to Cryptosporangium minutisporangium comb. nov. and Cryptosporangium aurantiacum sp. nov.

“…However, in their physiological characteristics, these species are distinguishable by the reduction of nitrate (Goodfellow et al, 1990). DNA-DNA hybridization studies may be required to confirm that they are phenotypically defined species.…”

“…Actinoplanes humidus and Actinoplanes consettensis, which were isolated from sediments of the River Derwent in the UK (Goodfellow et al, 1990), had 100 % sequence similarity. However, in their physiological characteristics, these species are distinguishable by the reduction of nitrate (Goodfellow et al, 1990).…”

“…Actinoplanes missouriensis IFO 13243 T and Actinoplanes auranticolor IFO 12245 T had 99n8% sequence similarity. However, these species have many differences in physiological characteristics (Goodfellow et al, 1990).…”

“…Actinoplanes caeruleus (Horan & Brodsky, 1986) was transferred to the genus Couchioplanes as Couchioplanes caeruleus (Tamura et al, 1994) on the basis of its morphology, chemotaxonomy and phylogeny. Goodfellow et al (1990) determined the chemotaxonomic and phenotypic characteristics of species of Actinoplanes and reported that the chemical and numerical taxonomic data supported the integrity of the genus. Koch et al (1996) analysed a 500 nt stretch of 16S rDNA from 17 valid species of the genus Actinoplanes and reported that two major phylogenetic groups were detected.…”

Catellatospora koreensis sp. nov., a novel actinomycete isolated from a gold-mine cave.

“…The family Micromonosporaceae forms a coherent group in the actinobacterial phylogenetic tree and has been placed in the suborder Micromonosporineae of the order Actinomycetales (Stackebrandt et al, 1997), with description of the family-specific 16S rDNA signatures. The genera of this family are readily differentiated from each other on the basis of chemotaxonomic, morphological and physiological properties (Asano & Kawamoto, 1986 ;Goodfellow et al, 1990 ;Rheims et al, 1998 ;Tamura et al, 1994Tamura et al, , 1997Yokota et al, 1993).…”