A representative genomic 16S rRNA sequence of
S. azurea NA-128
T was compared using NCBI BLAST [
16,
17] under default settings (e.g., considering only the high-scoring segment pairs (HSPs) from the best 250 hits) with the most recent release of the Greengenes database [
18] and the relative frequencies of taxa and keywords (reduced to their stem [
19]) were determined, weighted by BLAST scores. The most frequently occurring genera were
Saccharomonospora (47.9%),
Kocuria (17.7%),
Corynebacterium (9.4%),
Kibdelosporangium (6.0%) and
Prauserella (5.5%) (176 hits in total). Regarding the eight hits to sequences from members of the species, the average identity within HSPs was 99.5%, whereas the average coverage by HSPs was 99.8%. Regarding the 42 hits to sequences from other members of the genus, the average identity within HSPs was 97.0%, whereas the average coverage by HSPs was 98.3%. Among all other species, the one yielding the highest score was
Saccharomonospora xinjiangensis (AJ306300), which corresponded to an identity of 98.9% and an HSP coverage of 100.1%. (Note that the Greengenes database uses the INSDC (= EMBL/NCBI/DDBJ) annotation, which is not an authoritative source for nomenclature or classification.) The highest-scoring environmental sequence was FN667533 'stages composting process pilot scale municipal drum compost clone PS3734', which showed an identity of 100.0% and a HSP coverage of 97.9%. The most frequently occurring keywords within the labels of all environmental samples that produced hits were 'feedlot' (7.9%), 'top' (4.1%), 'beef, cattl, coli, escherichia, habitat, marc, neg, pen, primari, secondari, stec, surfac, synecolog' (3.9%), 'feedbunk' (2.3%) and 'compost' (1.7%) (74 hits in total). Environmental samples that yielded hits of a higher score than the highest scoring species were not found.
shows the phylogenetic neighborhood of S. azurea in a 16S rRNA based tree. The sequences of the three identical 16S rRNA gene copies in the genome do not differ from the previously published 16S rRNA sequence (Z38017).
| Table 1Classification and general features of S. azurea AN-128 T according to the MIGS recommendations [30]. |
Cells of
S. azurea NA-128
T form an irregularly branched vegetative mycelium of 0.3 to 0.4
μm diameter () [
1]. The monopodally branching aerial mycelium has a diameter of 0.3 to 0.6 μm [
1]; the mature mycelium and the spores are azure to cyaneus when grown on Oatmeal agar (ISP3) or on Czapek sucrose agar [
1]. Smooth, round spores are 0.8 to 1.0 mM long, mostly found on the aerial mycelium, but rarely on the substrate mycelium [
1]. No distinct soluble pigment was detectable [
1]. The growth range of strain NA-128
T spans from 24-40°C, with an optimum at 28-37°C [
1]. Strain NA-128
T grows well in up to 7% NaCl containing medium, but is inhibited at 10% NaCl [
1]. Physiological characteristics such as growth substrates, gelatin formation and peptonization of milk are described in detail by Runmao (1987) [
1].
Chemotaxonomy
The cell wall of strain AN-128
T contains
meso-diaminopimelic acid. Galactose and arabinose are present, indicating a type IV cell wall / type A whole cell sugar pattern [
1]. The fatty acids spectrum is dominated by almost 80% hexadecanoic acids:
iso-C
16:0 (27.0%), C
16:1 cis-9 (17.0%),
iso-C
16:0 2-OH (14.0%), C
16:0 (palmitic acid, 13.0%),
iso-C
16:1 H (7.0%),
anteiso-C
16:0 (1.0%) [
42]. There are no data available for polar lipids and quinines of this strain.