A representative genomic 16S rRNA sequence of C. algicola
was compared using NCBI BLAST 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 [5
] and the relative frequencies, weighted by BLAST scores, of taxa and keywords (reduced to their stem [6
]) were determined. The five most frequent genera were Cellulophaga
(5.4%) and Formosa
(4.7%) (135 hits in total). Regarding the 21 hits to sequences from members of the species, the average identity within HSPs was 95.8%, whereas the average coverage by HSPs was 94.9%. Regarding the 16 hits to sequences from other members of the genus, the average identity within HSPs was 94.7%, whereas the average coverage by HSPs was 94.7%. Among all other species, the one yielding the highest score was C. baltica
, which corresponded to an identity of 98.1% and a HSP coverage of 97.8%. The highest-scoring environmental sequence was GU452686 ('sediments coast oil polluted Black Sea coastal sediment clone 70SZ2'), which showed an identity of 96.5% and a HSP coverage of 98.1%. The five most frequent keywords within the labels of environmental samples which yielded hits were 'marin' (4.7%), 'water' (4.3%), 'sediment' (4.3%), 'sea' (3.5%) and 'coastal' (2.6%) (115 hits in total). Environmental samples which yielded hits of a higher score than the highest scoring species were not found.
The environmental samples database (env_nt) contains the marine metagenome clone ctg_1101667042524 (AACY022635173) isolated from Sargasso Sea near Bermuda, sharing 92% identity with IC166T
] (as of January 2011).
shows the phylogenetic neighborhood of C. algicola IC166T in a 16S rRNA based tree. The sequences of the five 16S rRNA gene copies in the genome differ from each other by up to two nucleotides, and differ by up to 14 nucleotides from the previously published 16S rRNA sequence (AF001366), which contains nine ambiguous base calls.
Figure 1 Phylogenetic tree highlighting the position of C. algicola IC166T relative to the other type strains within the family Flavobacteriaceae. The tree was inferred from 1,458 aligned characters [8,9] of the 16S rRNA gene sequence under the maximum likelihood (more ...)
The cells of C. algicola
are generally rod-shaped with rounded or tapered ends with cell lengths and widths ranging from 1.5 to 4 and 0.4 to 0.5 µm, respectively ( and ). C. algicola
is motile by gliding [1
]. Colonies on marine 2216 agar have yellow-orange pigmentation and a compact center, with a spreading edge possessing lighter pigmentation. Their consistency is slimy and they are slightly sunken into the agar [1
]. Flexirubin pigments are not formed. C. algicola
grows between 0.5 and 10% NaCl, with the best growth in the presence of about 2% NaCl. The temperature range for growth is between -2°C and 28°C, with an optimum between 15-20°C on solid media and at about 20-25°C in liquid media [1
]. The optimal pH for growth is about 7.5 [1
Scanning electron micrograph of C. algicola IC166T
Table 1 Classification and general features of C. algicola IC166T according to the MIGS recommendations .
The organism is strictly aerobic and chemoorganotrophic [1
]. C. algicola
can hydrolyze agar, starch, gelatine, carboxymethylcellulose (CMC), casein, Tween 80, tributyrin and L-tyrosine, but not urate, xanthine or dextran, when grown in presence of 1% L-tyrosine a reddish-brown diffusible pigment is formed [1
]. Nitrate reduction is positive, whereas denitrification, H2
S production and indole production are negative [1
]. Acid is formed oxidatively from D-galactose, D-glucose, D-fructose, sucrose, cellobiose, lactose and mannitol. Strain IC166T
is sensitive to ampicillin, streptomycin and carbenicillin and shows resistance to tetracycline [3
The fatty acid profile of seven Antarctic strains, including strain IC166T
, was analyzed by Bowman in 2000 [1
]. The hypothetical median representative of the Antarctic isolates was published. The predominant cellular fatty acids of these seven strains were branched-chain saturated and unsaturated fatty acids and straight-chain saturated and mono-unsaturated fatty acids, namely iso
(6.5%) and iso
]. The isoprenoid quinones of C. algicola
were not determined, but for C
the presence of MK-6 as the major lipoquinone was described [3
]. Polar lipids not have been studied.