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Int J Syst Evol Microbiol 55 (2005), 2113-2117; DOI  10.1099/ijs.0.63806-0
© 2005 International Union of Microbiological Societies

Dyadobacter hamtensis sp. nov., from Hamta glacier, located in the Himalayas, India

P. Chaturvedi, G. S. N. Reddy and S. Shivaji

Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500 007, India

Correspondence
S. Shivaji
shivas{at}ccmb.res.in


   ABSTRACT
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Strain HHS 11T was isolated from a water sample collected from the snout of Hamta glacier located in the Himalayan mountain ranges of India. Phenotypic, chemotaxonomic and phylogenetic analyses established the affiliation of the isolate to the genus Dyadobacter. HHS 11T possessed 96 and 95 % 16S rRNA gene sequence similarity with respect to Dyadobacter crusticola and Dyadobacter fermentans, respectively. Furthermore, strain HHS 11T differs from D. crusticola and D. fermentans in a number of phenotypic characteristics. These data suggest that strain HHS 11T represents a novel species of the genus Dyadobacter, for which the name Dyadobacter hamtensis sp. nov. is proposed. The type strain is HHS 11T (=JCM 12919T=MTCC 7023T).

The GenBank/EMBL/DDBJ accession number for the 16S rRNA gene sequence of strain HHS 11T is AJ619979.


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The genus Dyadobacter Chelius and Triplett 2000Go was created within the Flexibacter group to include Gram-negative rods that occur in pairs in young cultures but form chains of coccoid cells in older cultures. The cells are non-motile, oxidase- and catalase-positive, aerobic, capable of fermenting glucose and sucrose, do not hydrolyse cellulose or starch and produce a flexirubin-like pigment. These micro-organisms have a DNA G+C content of 48 mol% and are phylogenetically closely related to the genera Runella and Microscilla (Chelius & Triplett, 2000Go). To date, only two species of the genus, namely Dyadobacter fermentans, isolated from surface-sterilized Zea mays stems (Chelius & Triplett, 2000Go), and Dyadobacter crusticola, from biological soil crusts (Reddy and Garcia-Pichel, 2005Go), have been described. In this report, strain HHS 11T, an isolate from the Hamta glacier in the Himalayan mountain ranges in India, has been identified, on the basis of phenotypic, chemotaxonomic and phylogenetic analyses, as representing a novel species of the genus Dyadobacter.

Strain HHS 11T was isolated from a water sample collected from the ‘snout’ of the Hamta glacier located at a height of 4270 m above sea level. The sample was processed as described previously (Shivaji et al., 2005bGo) and pure colonies of bacteria were isolated by repeated streaking on plates containing nutrient agar [0·5 %, w/v, peptone (HiMedia); 0·3 %, w/v, beef extract (HiMedia); 0·5 %, w/v, NaCl; 1·5 %, w/v, agar; pH 7·0]. The plates were incubated at 22 °C for 3 days.

Nutrient agar medium was used for maintaining strain HHS 11T and for the determination of growth at various temperatures, at different pH values and in the presence of various concentrations of NaCl (Shivaji et al., 1989Go). Phenotypic characteristics such as colony morphology, cell morphology, motility, various enzyme activities and gas production (Hugh & Leifson, 1953Go), growth in various media, such as Ayers' and R2A (Ayers et al., 1919Go; Chelius & Triplett, 2000Go), and sensitivity to antibiotics at 22 °C were ascertained as described previously (Shivaji et al., 2004Go, 2005aGo) by using standard methods (Lanyi, 1987Go; Smibert & Krieg, 1994Go). Minimal medium [K2HPO4, 1·05 %, w/v; KH2PO4, 0·45 %, w/v; (NH4)2SO4, 0·1 %, w/v; agar, 1·5 %, w/v] was used to evaluate the ability of the culture to assimilate various carbon compounds (0·5 %, w/v) when provided as the only carbon source. The presence of a flexirubin-like pigment was tested according to the method of Weeks (1981)Go. Fatty acid methyl esters were prepared according to the method of Sato & Murata (1988)Go and analysed by GC (Shivaji et al., 2004Go; 2005aGo). The G+C content of the DNA was determined by the spectrophotometric method (Shivaji et al., 1989Go). D. fermentans NS 114T was used as a reference strain in studies relating to morphology, biochemical tests and the identification of fatty acids.

To establish the phylogenetic position of strain HHS 11T, DNA was purified and the 16S rRNA gene was amplified and sequenced as described previously (Shivaji et al., 2000Go). The almost-complete sequence of 1466 bases was manually aligned against the sequences of closely related species of Dyadobacter and other related genera using CLUSTAL W (Thompson et al., 1994Go) (Fig. 1Go) and phylogenetic affiliations were inferred using SEQBOOT, DNADIST, FITCH, DNAPARS and neighbour-joining, according to PHYLIP (Felsenstein, 1993Go). The Kimura two-parameter method was used for DNA distance calculation (Kimura, 1980Go), and bootstrap values were generated for 1000 replications of the data. In all cases, the input order of species added to the topology being constructed was randomized with the jumble option with a random seed of 7 and 10 replications. Majority rule (50 %) consensus trees were constructed (Page, 1996Go).



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  		Fig. 1. Neighbour-joining tree, based on 16S rRNA gene sequences (1455 bases), showing the phylogenetic relationship between D. hamtensis sp. nov. and species of the genera Dyadobacter, Runella, Spirosoma, Flectobacillus and Cytophaga and other closely related genera.

 
Strain HHS 11T conforms to the characteristics of the genus Dyadobacter in that it is Gram-negative, rod-shaped in both exponential and stationary phases, appears in pairs, is non-motile, aerobic, oxidase- and catalase-positive, ferments glucose but not sucrose, does not hydrolyse starch, has a DNA G+C content of 49 mol% and is phylogenetically related to Runella and Microscilla (see Fig. 1Go, Table 1Go and the species description for more details). In addition, HHS 11T produces a flexirubin-like yellow-coloured pigment, a characteristic feature of the genus Dyadobacter. The pigment was extracted according to the method of Weeks (1981)Go and the spectrum was obtained using a UV-visible spectrophotometer (UV-1601; Shimadzu): the pigment exhibited peaks at 422, 458 and 476 nm when extracted in ethanol. The addition of alkali (20 % KOH) changed the colour of the pigment to orange and also broadened the peak, thus confirming that it is a flexirubin-type pigment (Weeks, 1981Go).


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  		Table 1. Phenotypic characteristics that differentiate D. hamtensis sp. nov., D. crusticola and D. fermentans

All three species have the same colony shape and all stain Gram-negative, are non-motile, rod-shaped, positive for catalase, oxidase and {beta}-galactosidase, tolerate 1 % NaCl, grow at pH 6–8, grow at 25 and 30 °C, grow in R2A medium, utilize D-glucose, D-cellobiose, sucrose, D-trehalose, D-raffinose, D-lactose and inulin and are resistant to bacitracin (10 µg), nitrofurantoin (300 µg), penicillin (10 µg), vancomycin (10 µg) and erythromycin (15 µg). All are negative for urease, gelatinase, starch hydrolysis, citrate utilization, H2S production, nitrate reduction, the methyl red test, indole production, the Voges–Proskauer test, arginine dihydrolase, acid production from D-lactose, D-galactose, D-ribose, growth at pH 4 and pH 10, and the utilization of sodium succinate, starch and pyruvate. All are sensitive to doxycyline (30 µg) and tetracycline (30 µg). Symbols: +, positive; –, negative; –/+, variable; W, weak reaction; NA, data not available. Data for HHS 11T and D. fermentans NS-114T were obtained in the present study; data for D. crusticola C183-8T were taken from Reddy & Garcia-Pichel (2005Go).

 
The affiliation of strain HHS 11T to the genus Dyadobacter is further supported by the phylogenetic analysis based on the 16S rRNA gene sequence, which indicates that HHS 11T is related to the type strains of Dyadobacter species with validly published names, namely D. fermentans NS114T and D. crusticola C183-8T. At the 16S rRNA gene level, strain HHS 11T exhibits only 96 % similarity to D. crusticola C183-8T and 95 % similarity to D. fermentans NS114T. This difference of >4 % at the 16S rRNA gene sequence level between HHS 11T and the nearest phylogenetic neighbour suggests that strain HHS 11T represents a novel species, according to the accepted criteria (Stackebrandt & Goebel, 1994Go). DNA–DNA hybridization between strain HHS 11T and the nearest phylogenetic neighbours was not attempted since strains differing by >2·5 % at the 16S rRNA gene level are unlikely to exhibit >70 % similarity at whole-genome level (Stackebrandt & Goebel, 1994Go). The assignment of novel species status to HHS 11T is further strengthened on the basis of the differences the strain exhibits with respect to both of the Dyadobacter species with validly published names (Table 1Go). Distinct differences are also observed in the fatty acid composition of strain HHS 11T, D. crusticola CP183-8T and D. fermentans NS114T. In strain HHS 11T, the predominant fatty acids are iso-C15 : 1, iso-C15 : 0, C16 : 1{omega}5c, C16 : 1{omega}7c, C16 : 0 and iso-C17 : 0 3-OH. In D. crusticola CP183-8T, these fatty acids were also present; however, the level of iso-C15 : 0 was lower and the level of C16 : 1{omega}7c was higher. The fatty acid composition of D. fermentans NS114T was very similar to that of strain HHS 11T except that it contains iso-C15 : 0 3-OH and lacks C18 : 1 (Table 2Go). Thus, on the basis of the above phenotypic, chemotaxonomic and phylogenetic differences, it is proposed that strain HHS 11T be assigned as the type strain of a novel species of the genus Dyadobacter, for which the name Dyadobacter hamtensis sp. nov. is proposed.


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  		Table 2. Fatty acid composition (%) of D. hamtensis sp. nov. HHS 11T, D. crusticola CP183-8T and D. fermentans NS-114T

D. hamtensis sp. nov. HHS 11T and D. fermentans NS-114T were grown in R2A medium at 25 °C for the determination of the fatty acid composition. Data for D. crusticola CP183-8T are from Reddy & Garcia-Pichel (2005Go). –, Fatty acid not present.

 
Description of Dyadobacter hamtensis sp. nov.
Dyadobacter hamtensis (ham.ten'sis. N.L. masc. adj. hamtensis pertaining to the Hamta glacier).

Colonies of strain HHS 11T on nutrient agar medium are round (2–3 mm in diameter) and light yellow. Cells are aerobic, Gram-negative rods and are non-motile. Growth occurs between 10 and 37 °C and at pH 6–8, but not at pH 10. The optimum temperature and pH for growth are 22 °C and pH 7. Growth occurs in the presence of 11·6 % NaCl. Growth occurs on nutrient agar medium, Ayers' agar and R2A medium. The strain is positive for catalase, oxidase, phosphatase, arginine decarboxylase and {beta}-galactosidase, but negative for gelatinase, urease, lipase, lysine decarboxylase, arginine dihydrolase, utilization of citrate, H2S production, the methyl red test, the indole test, the Voges–Proskauer test, hydrolysis of aesculin, hydrolysis of starch and reduction of nitrate to nitrite. Acid is produced from D-xylose, D-arabinose and D-glucose, but not from D-ribose, D-fructose, D-galactose, L-rhamnose, sucrose, D-lactose, D-maltose or D-mannose. Utilizes L-arabinose, D-glucose, D-galactose, L-sorbose, sucrose, N-acetylglucosamine, methyl {alpha}-D-mannoside, methyl {alpha}-D-glucoside, L-fucose, melezitose, D-cellobiose, D-trehalose, D-lactose, D-raffinose, cellulose, amygdalin, dextran, glycogen, arbutin, salicin, glycerol, D-erythritol, D-adonitol, citrate, malonate, lactic acid, citric acid, 2-ketogluconate, inulin, sodium formate, sodium fumarate, sodium malate, sodium tartrate, sodium acetate, PEG, L-glycine, L-alanine, L-valine, L-leucine, L-isoleucine, L-serine, L-threonine, L-lysine, L-arginine, L-glutamic acid, L-aspartic acid, L-glutamine, L-asparagine, L-methionine, L-cysteine, L-tyrosine, L-phenylalanine, L-tryptophan, L-proline, L-histidine and L-creatinine as sole carbon sources. Does not utilize D-rhamnose, D-arabinose, L-melibiose, D-fructose, D-mannose, D-mannitol, D-xylose, L-xylose, D-ribose, D-maltose, D-sorbitol, dulcitol, myo-inositol, gluconate, hydroxybutyric acid, sodium succinate, sodium pyruvate, thioglycolate, starch, methanol or agar as sole carbon sources. Cells are sensitive to (µg per disc) ciprofloxacin (30), cefoperazone (75), cephotaxime (10), doxycycline (30), colistin (10), sulphamethazole (50), kanamycin (30), tetracycline (30), nalidixic acid (30), chloramphenicol (25), rifampicin (25), streptomycin (10), trimethoprim (25), norfloxacin (10), lomefloxacin (30), tobramycin (15) and amikacin (30), but resistant to cotrimoxazole (25), roxithromycin (30), nitrofurantoin (300), penicillin (10), cefuroxime (20), lincomycin (20), cefazolin (30), novobiocin (30), ampicillin (25 µg µl–1), amoxicillin (30), bacitracin (10), vancomycin (10) and erythromycin (15). The pigment is flexirubin-like. The G+C content of the DNA is 49 mol%. The major cellular fatty acids are C14 : 0, iso-C15 : 0, iso-C15 : 1, C16 : 1{omega}5c, C16 : 0, C16 : 1{omega}7c, C16 : 0 3-OH, C18 : 1 and iso-C17 : 0 3-OH.

The type strain, HHS 11T (=JCM 12919T=MTCC 7023T), was isolated from a glacial water sample.


   ACKNOWLEDGEMENTS
 
We thank the Department of Biotechnology, Government of India, New Delhi, India, for funding. Our special thanks go to Sri Deepak Srivastava, Sri Siddhartha Swaroop and his team from the Glaciology Department of Geological Survey of India, Faridabad, India, for their help with collection of the samples.


   REFERENCES
TOP
 ABSTRACT
 MAIN TEXT
 REFERENCES
 
Ayers, S. H., Rupp, P. & Johnson, W. T. (1919). A study of the alkali forming bacteria in milk. U S Dep Agric Bull 782.

Chelius, M. K. & Triplett, W. E. (2000). Dyadobacter fermentans gen. nov., sp. nov., a novel Gram-negative bacterium isolated from surface-sterilized Zea mays stems. Int J Syst Evol Microbiol 50, 751–758.[Abstract]

Felsenstein, J. (1993). PHYLIP (phylogeny inference package), version 3.5c. Distributed by the author. Department of Genome Sciences, University of Washington, Seattle, USA.

Hugh, R. & Leifson, E. (1953). The taxonomic significance of fermentative versus oxidative metabolism of carbohydrates by various gram negative bacteria. J Bacteriol 66, 24–26.[Free Full Text]

Kimura, M. (1980). A simple method for estimating evolutionary rates of base substitutions through comparative studies of nucleotide sequences. J Mol Evol 16, 111–120.[CrossRef][Medline]

Lanyi, B. (1987). Classical and rapid identification methods for medically important bacteria. Methods Microbiol 19, 1–67.

Page, R. D. M. (1996). TreeView: an application to display phylogenetic trees on personal computers. Comput Appl Biosci 12, 357–358.[Free Full Text]

Reddy, G. S. N. & Garcia-Pichel, F. (2005). Dyadobacter crusticola sp. nov., from biological soil crusts in the Colorado Plateau, USA, and an emended description of the genus Dyadobacter Chelius and Triplett 2000Go. Int J Syst Evol Microbiol 55, 1295–1299.[Abstract/Free Full Text]

Sato, N. S. & Murata, N. (1988). Membrane lipids. Methods Enzymol 167, 251–259.[CrossRef]

Shivaji, S., Rao, N. S., Saisree, L., Sheth, V., Reddy, G. S. & Bhargava, P. M. (1989). Isolation and identification of Pseudomonas spp. from Schirmacher Oasis, Antarctica. Appl Environ Microbiol 55, 767–770.[Abstract/Free Full Text]

Shivaji, S., Bhanu, N. V. & Aggarwal, R. K. (2000). Identification of Yersinia pestis as the causative organism of plague in India as determined by 16S rDNA sequencing and RAPD-based genomic fingerprinting. FEMS Microbiol Lett 189, 247–252.[CrossRef][Medline]

Shivaji, S., Reddy, G. S. N., Raghavan, P. U. M., Sarita, N. B. & Delille, D. (2004). Psychrobacter salsus sp. nov. and Psychrobacter adeliensis sp. nov. isolated from fast ice from Adelie Land, Antarctica. Syst Appl Microbiol 27, 628–635.[CrossRef][Medline]

Shivaji, S., Reddy, G. S. N., Suresh, K., Gupta, P., Chintalapati, S., Schumann, P., Stackebrandt, E. & Matsumoto, G. I. (2005a). Psychrobacter vallis sp. nov. and Psychrobacter aquaticus sp. nov., from Antarctica. Int J Syst Evol Microbiol 55, 757–762.[Abstract/Free Full Text]

Shivaji, S., Chaturvedi, P., Reddy, G. S. & Suresh, K. (2005b). Pedobacter himalayensis sp. nov., from the Hamta glacier located in the Himalayan mountain ranges of India. Int J Syst Evol Microbiol 55, 1083–1088.[Abstract/Free Full Text]

Smibert, R. M. & Krieg, N. R. (1994). Phenotypic characterization. In Methods for General and Molecular Bacteriology, pp. 607–654. Edited by P. Gerhardt. Washington, DC: American Society for Microbiology.

Stackebrandt, E. & Goebel, B. M. (1994). A place for DNA-DNA reassociation and 16S rRNA sequence analysis in the present species definition in bacteriology. Int J Syst Bacteriol 44, 846–849.[Abstract/Free Full Text]

Thompson, J. D., Higgins, D. G. & Gibson, T. J. (1994). CLUSTAL W: improving the sensitivity of progressive multiple sequence alignment through sequence weighting, position-specific gap penalties and weight matrix choice. Nucleic Acids Res 22, 4673–4680.[Abstract/Free Full Text]

Weeks, O. B. (1981). Preliminary studies of the pigments of Flavobacterium breve NCTC 11099 and Flavobacterium odoratum NCTC 11036. In The Flavobacterium–Cytophaga Group, pp. 108–114. Edited by H. Reichenbach & O. B. Weeks. Weinheim: Gesellschaft fur Biotechnologische forschung.




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