|
|
||||||||
1 Korea Research Institute of Bioscience and Biotechnology (KRIBB), PO Box 115, Yusong, Taejon, Korea
2 National Research Laboratory of Molecular Ecosystematics, Institute of Probionic, Probionic Corporation, Bio-venture Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), PO Box 115, Yusong, Taejon, Korea
3 Department of Food and Life Science, Sungkyunkwan University, Chunchun-dong 300, Jangan-gu, Suwon, Korea
Correspondence
Yong-Ha Park
yhpark{at}kribb.re.kr
| ABSTRACT |
|---|
|
|
|---|
The GenBank/EMBL/DDBJ accession numbers for the 16S rDNA sequences of strains SW-72T and SW-93 are AF541966 and AF541965, respectively.
Electron micrographs and a full phylogenetic tree are available as supplementary material in IJSEM Online.
| MAIN TEXT |
|---|
|
|
|---|
In this study, we describe two Gram-positive or -variable, endospore-forming, slightly halophilic rods, strains SW-72T and SW-93, that were isolated from sea water of the East Sea and the Yellow Sea in Korea, respectively. The results of 16S rDNA sequence comparison indicated that these organisms are related phylogenetically to members of Bacillus rRNA group 6. Accordingly, the aim of the present work was to establish the exact taxonomic positions of strains SW-72T and SW-93 by using a combination of phenotypic characterization, detailed phylogenetic analysis based on 16S rDNA sequences and genomic relatedness.
Strains SW-72T and SW-93 were isolated by the dilution-plating technique on marine agar 2216 (MA) (Difco). Cell biomass of strains SW-72T and SW-93 for cell-wall and isoprenoid quinone analyses and for DNA extraction was obtained from cultures in marine broth 2216 (MB) (Difco) at 30 °C. For fatty acid methyl ester analysis, cell mass of strains SW-72T and SW-93 was obtained from agar plates after cultivation for 2 days at 30 °C on MA. Cell morphology was examined by light microscopy (using a Nikon E600 microscope) and transmission electron microscopy. Flagellation was examined by using transmission electron microscopy with cells from exponentially growing cultures. Gram-reaction was determined by using the bioMérieux Gram-stain kit according to the manufacturer's instructions. Catalase and oxidase activities, hydrolysis of casein and starch and phenylalanine deamination were determined as described by Cowan & Steel (1965)
. Aesculin hydrolysis and nitrate reduction were determined according to the method of Lanyi (1987)
, with the addition of 3 % (w/v) NaCl. Hydrolysis of gelatin and Tweens 20, 40, 60 and 80 was determined as described by Cowan & Steel (1965)
, with the modification that artificial sea water was used. Artificial sea water contained the following [(l distilled water)1]: 23·6 g NaCl, 0·64 g KCl, 4·53 g MgCl2.6H2O, 5·94 g MgSO4.7H2O and 1·3 g CaCl2.2H2O (Levring, 1946
). Hydrolysis of hypoxanthine, tyrosine and xanthine was performed on MA, with substrate concentrations as described by Cowan & Steel (1965)
. Acid production from carbohydrates was determined as described by Leifson (1963)
. Growth under anaerobic conditions was determined after incubation in an anaerobic chamber with MA that had been prepared anaerobically by using nitrogen. Growth in the absence of NaCl was investigated in trypticasesoy broth that lacked NaCl. pH range for growth was determined in MB that was adjusted to pH values 4·5, 5·0, 5·5, 6·0, 6·5, 7·0, 7·5, 8·0, 8·5, 9·0, 9·5 and 10·0. Growth at various NaCl concentrations was investigated in MB. Growth at various temperatures (450 °C) was measured on MA.
The isomer type of diamino acid of the cell-wall peptidoglycan was determined by the method of Komagata & Suzuki (1987)
. Menaquinones were analysed as described previously (Komagata & Suzuki, 1987
) by using reverse-phase HPLC. For quantitative analysis of cellular fatty acid compositions, a loop of cell mass was harvested and fatty acid methyl esters were prepared and identified by following the instructions of the Microbial Identification system (MIDI). Chromosomal DNA was isolated and purified according to a method described previously (Yoon et al., 1996
), with the exception that ribonuclease T1 was used together with ribonuclease A. DNA G+C content was determined by the method of Tamaoka & Komagata (1984)
. DNA was hydrolysed and the resultant nucleotides were analysed by reverse-phase HPLC. 16S rDNA was amplified by PCR using two universal primers, as described previously (Yoon et al., 1998
). Sequencing of the amplified 16S rDNA and phylogenetic analysis were performed as described by Yoon et al. (2003)
. DNADNA hybridization was performed fluorometrically by the method of Ezaki et al. (1989)
, using photobiotin-labelled DNA probes and microdilution wells. Hybridization was performed by using five replicates for each sample; the highest and lowest values obtained for each sample were excluded and the remaining three values were used to calculate similarity values. The DNADNA relatedness values quoted are means of these three values.
Strain SW-72T had no flagella, whereas strain SW-93 was motile by means of peritrichous flagella (see Supplementary Figure A, available in IJSEM Online). Maximum growth temperatures of strains SW-72T and SW-93 were 40 and 42 °C, respectively. Strain SW-72T grew at pH values in the approximate range 5·09·5, with an optimum at pH 6·07·0. Strain SW-93 grew better at pH 8·59·5 than at neutral pH. Strain SW-93 grew at pH 5·0, but not at pH 4·5. Neither strain showed any growth in the absence of NaCl. Strains SW-72T and SW-93 did not grow in the presence of >20 and >21 % (w/v) NaCl, respectively. Phenotypic properties of strains SW-72T and SW-93 are shown in Table 1
or are given in the species description (see below).
|
|
|
Analysis of 16S rDNA sequences reveals that strains SW-72T and SW-93 have a high degree of relatedness, there being only five 16S rDNA nucleotide sequence differences (99·7 % similarity) (Fig. 1
). However, the DNADNA relatedness value for strains SW-72T and SW-93 is much lower than 70 %, a value that has been recognized as the threshold for species delineation (Wayne et al., 1987
). The same result was obtained from repeated tests, as well as from cross-hybridization between DNA extracted from the two strains. The possibility of contamination of DNA from strains SW-72T and SW-93 was investigated by sequencing 16S rDNA that was amplified from DNA of each strain. However, there was no contamination of the DNA of the two strains. Strains SW-72T and SW-93 are similar in their phenotypic characteristics, although there are minor differences in some features. Therefore, it is better that these two are considered as members of genomic species that cannot be differentiated phenotypically from each other (Wayne et al., 1987
). The taxonomic positions of strains SW-72T and SW-93 within the genus Bacillus, particularly Bacillus rRNA group 6, become distinct from the results of 16S rDNA sequence comparison (Fig. 1
). 16S rDNA sequence similarity values obtained for strains SW-72T and SW-93 and the type strains of Bacillus species are low enough to exclude the possibility of assigning strains SW-72T and SW-93 to any existing Bacillus species (Stackebrandt & Goebel, 1994
).
On the basis of these data, we propose that strain SW-72T should be placed within the genus Bacillus as the type strain of a novel species, Bacillus hwajinpoensis sp. nov., and that strain SW-93 should be placed within the genus Bacillus as an unnamed Bacillus genomospecies.
Description of Bacillus hwajinpoensis sp. nov.
Bacillus hwajinpoensis (hwa.jin.po.en'sis. N.L. adj. hwajinpoensis of Hwajinpo, a beach of the East Sea in Korea, where the type strain was isolated).
Cells are aerobic rods, 1·01·3 µm wide and 2·54·0 µm long. Gram-positive, but Gram-variable in old cultures. Non-motile. Central or subterminal ellipsoidal endospores are observed in swollen sporangia. Colonies are smooth, circular to slightly irregular, slightly raised, light yellow in colour and 24 mm in diameter after 3 days cultivation at 30 °C on MA. Optimal growth temperature is 3035 °C. Growth occurs at 10 and 40 °C, but not at 4 °C or above 41 °C. Optimal pH for growth is 6·07·0. Growth is observed at pH 5·0, but not at pH 4·5. Optimal growth occurs in the presence of 25 % (w/v) NaCl. Growth occurs in the presence of 19 % (w/v) NaCl, but not without NaCl or in the presence of >20 % (w/v) NaCl. No growth occurs under anaerobic conditions on MA. Urease-negative. Aesculin is hydrolysed. Hypoxanthine, tyrosine and xanthine are not hydrolysed. Acid is produced from stachyose and D-mannitol. Cell-wall peptidoglycan contains meso-diaminopimelic acid. Predominant menaquinone is MK-7. Major fatty acid is anteiso-C15 : 0. DNA G+C content is 40·9 mol% (determined by HPLC). Other phenotypic properties are given in Table 1
.
The type strain, SW-72T (=KCCM 41641T=JCM 11807T), was isolated from sea water from Hwajinpo Beach, East Sea, Korea.
Description of unnamed Bacillus genomospecies
Cells are aerobic rods, 0·71·0 µm wide and 1·53·0 µm long. Motile by means of peritrichous flagella. Growth occurs at 10 and 42 °C, but not at 4 °C or above 43 °C. Optimal pH for growth is 8·59·5. Growth occurs in the presence of 20 % (w/v) NaCl, but not without NaCl or in the presence of >21 % (w/v) NaCl. Acid is not produced from stachyose. DNA G+C content is 41·0 mol% (determined by HPLC). Other phenotypic properties are identical to those of B. hwajinpoensis and are given in Table 1
.
Strain SW-93 (=KCCM 41640=JCM 11806) was isolated from sea water from Baekryung Island, Yellow Sea, Korea.
| ACKNOWLEDGEMENTS |
|---|
| REFERENCES |
|---|
|
|
|---|
Ash, C., Priest, F. G. & Collins, M. D. (1993). Molecular identification of rRNA group 3 bacilli (Ash, Farrow, Wallbanks and Collins) using a PCR probe test. Proposal for the creation of a new genus Paenibacillus. Antonie van Leeuwenhoek 64, 253260.[CrossRef][Medline]
Cowan, S. T. & Steel, K. J. (1965). Manual for the Identification of Medical Bacteria. London: Cambridge University Press.
Ezaki, T., Hashimoto, Y. & Yabuuchi, E. (1989). Fluorometric deoxyribonucleic acid-deoxyribonucleic acid hybridization in microdilution wells as an alternative to membrane filter hybridization in which radioisotopes are used to determine genetic relatedness among bacterial strains. Int J Syst Bacteriol 39, 224229.
Heyrman, J., Balcaen, A., Rodriguez-Diaz, M., Logan, N. A., Swings, J. & De Vos, P. (2003). Bacillus decolorationis sp. nov., isolated from biodeteriorated parts of the mural paintings at the Servilia tomb (Roman necropolis of Carmona, Spain) and the Saint-Catherine chapel (Castle Herberstein, Austria). Int J Syst Evol Microbiol 53, 459463.
Komagata, K. & Suzuki, K. (1987). Lipid and cell wall analysis in bacterial systematics. Methods Microbiol 19, 161206.
Lanyi, B. (1987). Classical and rapid identification methods for medically important bacteria. Methods Microbiol 19, 167.
Leifson, E. (1963). Determination of carbohydrate metabolism of marine bacteria. J Bacteriol 85, 11831184.
Levring, T. (1946). Some culture experiments with Ulva and artificial sea water. K Fysiogr Sällsk Lund Förh 16, 4556.
Li, Z., Kawamura, Y., Shida, O., Yamagata, S., Deguchi, T. & Ezaki, T. (2002). Bacillus okuhidensis sp. nov., isolated from the Okuhida spa area of Japan. Int J Syst Evol Microbiol 52, 12051209.[Abstract]
Nazina, T. N., Tourova, T. P., Poltaraus, A. B. & 8 other authors (2001). Taxonomic study of aerobic thermophilic bacilli: descriptions of Geobacillus subterraneus gen. nov., sp. nov. and Geobacillus uzenensis sp. nov. from petroleum reservoirs and transfer of Bacillus stearothermophilus, Bacillus thermocatenulatus, Bacillus thermoleovorans, Bacillus kaustophilus, Bacillus thermoglucosidasius and Bacillus thermodenitrificans to Geobacillus as the new combinations G. stearothermophilus, G. thermocatenulatus, G. thermoleovorans, G. kaustophilus, G. thermoglucosidasius and G. thermodenitrificans. Int J Syst Evol Microbiol 51, 433446.[Abstract]
Nielsen, P., Rainey, F. A., Outtrup, H., Priest, F. G. & Fritze, D. (1994). Comparative 16S rDNA sequence analysis of some alkaliphilic bacilli and the establishment of a sixth rRNA group within the genus Bacillus. FEMS Microbiol Lett 117, 6165.[CrossRef]
Nielsen, P., Fritze, D. & Priest, F. G. (1995). Phenetic diversity of alkaliphilic Bacillus strains: proposal for nine new species. Microbiology 141, 17451761.
Priest, F. G. (1981). DNA homology in the genus Bacillus. In The Aerobic Endospore-Forming Bacteria, pp. 3357. Edited by R. C. W. Berkeley & M. Goodfellow. London: Academic Press.
Rainey, F. A., Fritze, D. & Stackebrandt, E. (1994). The phylogenetic diversity of thermophilic members of the genus Bacillus as revealed by 16S rDNA analysis. FEMS Microbiol Lett 115, 205211.[CrossRef][Medline]
Schlesner, H., Lawson, P. A., Collins, M. D., Weiss, N., Wehmeyer, U., Völker, H. & Thomm, M. (2001). Filobacillus milensis gen. nov., sp. nov., a new halophilic spore-forming bacterium with Orn-D-Glu-type peptidoglycan. Int J Syst Evol Microbiol 51, 425431.[Abstract]
Shida, O., Takagi, H., Kadowaki, K. & Komagata, K. (1996). Proposal for two new genera, Brevibacillus gen. nov. and Aneurinibacillus gen. nov. Int J Syst Bacteriol 46, 939946.
Slepecky, R. A. & Hemphill, H. E. (1991). The genus Bacillus nonmedical. In The Prokaryotes, vol. 2, pp. 16631696. Edited by A. Balows, H. G. Trüper, M. Dworkin, W. Harder & K.-H. Schleifer. New York: Springer.
Spring, S., Ludwig, W., Marquez, M. C., Ventosa, A. & Schleifer, K.-H. (1996). Halobacillus gen. nov., with descriptions of Halobacillus litoralis sp. nov. and Halobacillus trueperi sp. nov., and transfer of Sporosarcina halophila to Halobacillus halophilus comb. nov. Int J Syst Bacteriol 46, 492496.
Stackebrandt, E. & Goebel, B. M. (1994). Taxonomic note: a place for DNA-DNA reassociation and 16S rRNA sequence analysis in the present species definition in bacteriology. Int J Syst Bacteriol 44, 846849.
Stackebrandt, E. & Liesack, W. (1993). Nucleic acids and classification. In Handbook of New Bacterial Systematics, pp. 152189. Edited by M. Goodfellow & A. G. O'Donnell. London: Academic Press.
Tamaoka, J. & Komagata, K. (1984). Determination of DNA base composition by reverse-phase high-performance liquid chromatography. FEMS Microbiol Lett 25, 125128.
Wainø, M., Tindall, B. J., Schumann, P. & Ingvorsen, K. (1999). Gracilibacillus gen. nov., with description of Gracilibacillus halotolerans gen. nov., sp. nov.; transfer of Bacillus dipsosauri to Gracilibacillus dipsosauri comb. nov., and Bacillus salexigens to the genus Salibacillus gen. nov., as Salibacillus salexigens comb. nov. Int J Syst Bacteriol 49, 821831.
Wayne, L. G., Brenner, D. J., Colwell, R. R. & 9 other authors (1987). International Committee on Systematic Bacteriology. Report of the ad hoc committee on reconciliation of approaches to bacterial systematics. Int J Syst Bacteriol 37, 463464.
Wisotzkey, J. D., Jurtshuk, P., Jr, Fox, G. E., Deinhard, G. & Poralla, K. (1992). Comparative sequence analyses on the 16S rRNA (rDNA) of Bacillus acidocaldarius, Bacillus acidoterrestris, and Bacillus cycloheptanicus and proposal for creation of a new genus, Alicyclobacillus gen. nov. Int J Syst Bacteriol 42, 263269.
Yoon, J.-H., Kim, H., Kim, S.-B., Kim, H.-J., Kim, W. Y., Lee, S. T., Goodfellow, M. & Park, Y.-H. (1996). Identification of Saccharomonospora strains by the use of genomic DNA fragments and rRNA gene probes. Int J Syst Bacteriol 46, 502505.
Yoon, J.-H., Lee, S. T. & Park, Y.-H. (1998). Inter- and intraspecific phylogenetic analysis of the genus Nocardioides and related taxa based on 16S rDNA sequences. Int J Syst Bacteriol 48, 187194.
Yoon, J.-H., Weiss, N., Lee, K.-C., Lee, I.-S., Kang, K. H. & Park, Y.-H. (2001). Jeotgalibacillus alimentarius gen. nov., sp. nov., a novel bacterium isolated from jeotgal with L-lysine in the cell wall, and reclassification of Bacillus marinus Rüger 1983 as Marinibacillus marinus gen. nov., comb. nov. Int J Syst Evol Microbiol 51, 20872093.[Abstract]
Yoon, J.-H., Kim, I.-G., Shin, D.-Y., Kang, K. H. & Park, Y.-H. (2003). Microbulbifer salipaludis sp. nov., a moderate halophile isolated from a Korean salt marsh. Int J Syst Evol Microbiol 53, 5357.
Yumoto, I., Yamaga, S., Sogabe, Y., Nodasaka, Y., Matsuyama, H., Nakajima, K. & Suemori, A. (2003). Bacillus krulwichiae sp. nov., a halotolerant obligate alkaliphile that utilizes benzoate and m-hydroxybenzoate. Int J Syst Evol Microbiol 53, 15311536.
This article has been cited by other articles:
![]() |
Y.-G. Chen, Y.-Q. Zhang, Y.-X. Wang, Z.-X. Liu, H.-P. Klenk, H.-D. Xiao, S.-K. Tang, X.-L. Cui, and W.-J. Li Bacillus neizhouensis sp. nov., a halophilic marine bacterium isolated from a sea anemone Int J Syst Evol Microbiol, December 1, 2009; 59(12): 3035 - 3039. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Liu, Y. Zhou, R. Liu, K.-Y. Zhang, and R. Lai Bacillus solisalsi sp. nov., a halotolerant, alkaliphilic bacterium isolated from soil around a salt lake Int J Syst Evol Microbiol, June 1, 2009; 59(6): 1460 - 1464. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. Cerritos, P. Vinuesa, L. E. Eguiarte, L. Herrera-Estrella, L. D. Alcaraz-Peraza, J. L. Arvizu-Gomez, G. Olmedo, E. Ramirez, J. L. Siefert, and V. Souza Bacillus coahuilensis sp. nov., a moderately halophilic species from a desiccation lagoon in the Cuatro Cienegas Valley in Coahuila, Mexico Int J Syst Evol Microbiol, April 1, 2008; 58(4): 919 - 923. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Albuquerque, I. Tiago, M. Taborda, M. F. Nobre, A. Verissimo, and M. S. da Costa Bacillus isabeliae sp. nov., a halophilic bacterium isolated from a sea salt evaporation pond Int J Syst Evol Microbiol, January 1, 2008; 58(1): 226 - 230. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. S. Borchert, P. Nielsen, I. Graeber, I. Kaesler, U. Szewzyk, T. Pape, G. Antranikian, and T. Schafer Bacillus plakortidis sp. nov. and Bacillus murimartini sp. nov., novel alkalitolerant members of rRNA group 6 Int J Syst Evol Microbiol, December 1, 2007; 57(12): 2888 - 2893. [Abstract] [Full Text] [PDF] |
||||
![]() |
Q.-f. Wang, W. Li, Y.-l. Liu, H.-h. Cao, Z. Li, and G.-q. Guo Bacillus qingdaonensis sp. nov., a moderately haloalkaliphilic bacterium isolated from a crude sea-salt sample collected near Qingdao in eastern China Int J Syst Evol Microbiol, May 1, 2007; 57(5): 1143 - 1147. [Abstract] [Full Text] [PDF] |
||||
![]() |
J.-H. Yoon, S.-J. Kang, and T.-K. Oh Donghicola eburneus gen. nov., sp. nov., isolated from seawater of the East Sea in Korea Int J Syst Evol Microbiol, January 1, 2007; 57(1): 73 - 76. [Abstract] [Full Text] [PDF] |
||||
![]() |
J.-M. Lim, C. O. Jeon, and C.-J. Kim Bacillus taeanensis sp. nov., a halophilic Gram-positive bacterium from a solar saltern in Korea Int J Syst Evol Microbiol, December 1, 2006; 56(12): 2903 - 2908. [Abstract] [Full Text] [PDF] |
||||
![]() |
J.-M. Lim, C. O. Jeon, S.-M. Lee, J.-C. Lee, L.-H. Xu, C.-L. Jiang, and C.-J. Kim Bacillus salarius sp. nov., a halophilic, spore-forming bacterium isolated from a salt lake in China Int J Syst Evol Microbiol, February 1, 2006; 56(2): 373 - 377. [Abstract] [Full Text] [PDF] |
||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| INT J SYST EVOL MICROBIOL | MICROBIOLOGY | J GEN VIROL |
| J MED MICROBIOL | ALL SGM JOURNALS | |