Original Article

Isolation of a novel halothermophilic strain of the genus Gracilibacillus from Howz-e Sultan hypersaline lake in Iran

Abstract

Background and Objectives: Halothermophilic bacteria are adapted to high osmolarity and can grow in high saline environments and high temperatures. This study was aimed at the isolation of halothermophilic bacteria from Howz-e Sultan hypersaline lake in the central desert zone in Iran.
Materials and Methods: Samples were collected and after preparing dilutions, the samples were cultured on Molten haloid agar with different salt concentrations (5-35%), then the plates were incubated at 35-70ºC in both aerobic and anaerobic conditions. Biochemical characterizations, utilization of carbon sources, production of exoenzymes and antibiotic susceptibility were investigated. Taxonomic and phylogenetic analyses were performed using 16S rRNA gene sequences.
Results: One of the isolated bacteria was found to be Gram-positive, hyperhalophilic, thermophilic, endospore-forming, and was named as 1-9 h isolate. The bacterial cells were bacilli-shaped, which produced endospores at a subterminal position. This isolate was an aerobe and facultative anaerobe and grew between pH 5.0 and 10.0 (optimal growth at pH 7.0-7.5), at temperature between 15°C and 65°C (optimal growth at 40-45°C) and at salinity of 9-32% (w/v) NaCl, growing optimally at 18% (w/v) NaCl. On the basis of 16S rRNA gene sequence analysis, isolate 1-9 h belongs to the genus Bacillus within the phylum Firmicutes and showed the closest phylogenetic similarity to Gracilibacillus sp. IBP-V003 (99.0%).
Conclusion: Based on the results of its phenotypic and genotypic properties, strain 1-9 h represents a novel strain of the genus Gracilibacillus. It can be used in various fields of industry and biotechnology.

1. Vreeland RH, Rosenzweig WD, Powers DW. Isolation of a 250 million-year-old halotolerant bacterium from a primary salt crystal. Nature 2000;407:897-900.
2. Banciu HL, Enache M, Montalvo Rodriguez RM, Oren A, Ventosa A. Ecology and physiology of halophilic microorganisms-thematic issue based on papers presented at halophiles 2019-12th international conference on halophilic microorganisms, Cluj-Napoca, Romania, 24-28 June, 2019. FEMS Microbiol Lett 2019; 366:fnz250.
3. Deutch CE. Characterization of a salt‐tolerant extracellular a‐amylase from Bacillus dipsosauri. Lett Appl Microbiol 2002;35:78-84.
4. Carrasco IJ, Marquez MC, Yanfen X, Ma Y, Cowan DA, Jones BE, et al. Gracilibacillus orientalis sp. nov., a novel moderately halophilic bacterium isolated from a salt lake in Inner Mongolia, China. Int J Syst Evol Microbiol 2006;56:599-604.
5. Jeon CO, Lim JM, Jang HH, Park DJ, Xu LH, Jiang CL, et al. Gracilibacillus lacisalsi sp. nov., a halophilic gram-positive bacterium from a salt lake in China. Int J Syst Evol Microbiol 2008;58:2282-2286.
6. Tang SK, Wang Y, Lou K, Mao PH, Jin X, Jiang CL, et al. Gracilibacillus saliphilus sp. nov., a moderately halophilic bacterium isolated from a salt lake. Int J Syst Evol Microbiol 2009;59:1620-1624.
7. Ahmed I, Yokota A, Fujiwara T. Gracilibacillus boraciitolerans sp. nov., a highly boron-tolerant and moderately halotolerant bacterium isolated from soil. Int J Syst Evol Microbiol 2007;57:796-802.
8. Chen YG, Cui XL, Zhang YQ, Li WJ, Wang YX, Xu LH, et al. Gracilibacillus halophilus sp. nov., a moderately halophilic bacterium isolated from saline soil. Int J Syst Evol Microbiol 2008;58:2403-2408.
9. Chen YG, Cui XL, Zhang YQ, Li WJ, Wang YX, Xu LH, et al. Gracilibacillus quinghaiensis sp. nov., isolated from salt-lake sediment in the Qaidam Basin, north-west China. Syst Appl Microbiol 2008;31:183-189.
10. Mimura H, Nagata S. Isolation of halotolerant microorganisms from seawater around the Inland sea in western Japan. Microbes Environ 2000;15:217- 221.
11. Fendrihan S, Legat A, Pfaffenhuemer M, Gruber C, Weidler G, Gerbl F, et al. Extremely halophilic archaea and the issue of long-term microbial survival. Rev Environ Sci Biotechnol 2006;5:203-218.
12. Goyal N, Gupta JK, Soni SK. A novel raw starch digesting thermostable α-amylase from Bacillus sp.I-3 and its use in the direct hydrolysis of raw potato starch. Enzyme Microb Tech 2005;37:723-734.
13. Chakraborty S, Khopade A, Kokare C, Mahadik K, Chopade B. Isolation and characterization of novel α-amylase from marine Streptomyces sp. D1. J Mol Catal B: Enzymatic 2009;58:17-23.
14. Namwong S, Tanasupawat S, Smitinont T, Visessanguan W, Kudo T, Itoh T. Isolation of Lentibacillus salicampi strains and Lentibacillus juripiscarius sp. nov. from fish sauce in Thailand. Int J Syst Evol Microbiol 2005;55:315-320.
15. Amoozegar MA, Bagheri M, Makhdoumi-Kakhki A, Didari M, Schumann P, Nikou MM, et al. Aliicoccus persicus gen. nov., sp. nov., a halophilic member of the firmicutes isolated from a hypersaline lake. Int J Syst Evol Microbiol 2014;64:1964-1969.
16. Mata JA, Martínez-Cánovas J, Quesada E, Béjar V. A detailed phenotypic characterization of the type strains of halomonas species. Syst Appl Microbiol 2002;25:360-375.
17. Oren A, Larimer F, Richardson P, Lapidus A, Csonka LN. How to be moderately halophilic with broad salt tolerance: clues from the genome of Chromohalobacter salexigens. Extremophiles 2005;9:275-279.
18. Orcutt BN, Sylvan JB, Knab NJ, Edwards KJ. Microbial ecology of the dark ocean above, at, and below the seafloor. Microbiol Mol Biol Rev 2011;75:361-422.
19. Bozal N, Montes MJ, Tudela E, Guinea J. Characterization of several Psychrobacter strains isolated from Antarctic environments and description of Psychrobacter luti sp. nov. and Psychrobacter fozii sp. nov. Int J Syst Evol Microbiol 2003;53:1093-1100.
20. Grossart HP, Steward GF, Martinez J, Azam F. A simple, rapid method for demonstrating bacterial flagella. Appl Environ Microbiol 2000;66:3632-3636.
21. Barrow GI, Feltham RKA (2004). Cowan and Steel's manual for the identification of medical bacteria. 3rd ed. Cambridge University Press. Cambridge.
22. Tindall BJ, Sikorski J, Smibert RA, Krieg NR (2007). Phenotypic characterization and the principles of comparative systematics. In: Methods for general and molecular microbiology. Eds, CA Reddy, TJ Beveridge, JA Breznak, GA Marzluf, M Schmidt, LR Snyder. 3rd ed. ASM Press, Washington DC, pp.330-393.
23. Bagheri M, Amoozegar MA, Schumann P, Didari M, Mehrshad M, Sproer C, et al. Ornithinibacillus halophilus sp. nov., a moderately halophilic, gram-stain-positive, endospore-forming bacterium from a hypersaline lake. Int J Syst Evol Microbiol 2013;63:844-848.
24. Jorgensen JH, Ferraro MJ. Antimicrobial susceptibility testing: a review of general principles and contemporary practices. Clin Infect Dis 2009;49:1749-1755.
25. Tamura K, Dudley J, Nei M, Kumar S. MEGA 4: molecular evolutionary genetics analysis (MEGA) software version 4.0. Mol Biol Evol 2007;24:1596-1599.
26. Amoozegar MA, Didari M, Bagheri M, Fazeli SAS, Schumann P, Sproer C, et al. Bacillus salsus sp. nov., a halophilic bacterium from a hypersaline lake. Int J Syst Evol Microbiol 2013;63:3324-3329.
27. Andrei AS, Robeson MS 2nd, Baricz A, Coman C, Muntean V, Lonescu A, et al. Contrasting taxonomic stratification of microbial communities in two hypersaline meromictic lakes. ISME J 2015;9:2642-2656.
28. Chua MJ, Campen RL, Wahl L, Grzymski JJ, Mikucki JA. Genomic and physiological characterization and description of Marinobacter gelidimuriae sp. nov., a psychrophilic, moderate halophile from blood falls, an Antarctic subglacial brine. FEMS Microbiol Ecol 2018;94: 10.1093/femsec/fiy021.
29. Wolters M, Borst A, Pfeiffer F, Soppa J. Bioinformatic and genetic characterization of three genes localized adjacent to the major replication origin of Haloferax volcanii. FEMS Microbiol Lett 2019;366:fnz238.
Files
IssueVol 13 No 3 (2021) QRcode
SectionOriginal Article(s)
Published2021-06-05
Keywords
Bacillaceae; Halobacteriales; Salinity; Extreme environments

Rights and permissions
Creative Commons License This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
How to Cite
1.
Mahmoudnia F. Isolation of a novel halothermophilic strain of the genus Gracilibacillus from Howz-e Sultan hypersaline lake in Iran. Iran J Microbiol. 13(3):399-406.