ABSTRACT
The facultative intracellular Gram-negative bacterium Brucella melitensis causes brucellosis in domestic and wild mammals, and it is a dominant pathogen responsible for human disease. This study reports the whole-genome sequencing of B. melitensis strain QY1, isolated from sheep suffering from abortion and arthritis in 2015 in Gansu, China.
GENOME ANNOUNCEMENT
Brucella spp. are Gram-negative and intracellular pathogens that cause animal brucellosis, a disease that leads to abortion and infertility in livestock, resulting in severe economic losses and threats to human health (1, 2). In recent years, brucellosis has reemerged in animals in China. Brucella melitensis not only causes the most cases of brucellosis in sheep but is also an important pathogen responsible for human disease (3, 4).
Here, we present the genome sequence of B. melitensis QY1, which was isolated in China from the spleen of an aborted sheep fetus. B. melitensis QY1 is an epidemic isolate causing typical clinical symptoms (e.g., arthritis and abortion) and histopathologic changes (e.g., significant necrosis in the placenta villi and slight congestion in spleen, with white myeloid lymphocyte density).
Genomic DNA was extracted with the DNeasy blood and tissue kit (Qiagen, Valencia, CA). This genome was sequenced by PacBio technology after PacBio RSII and Illumina HiSeq DNA libraries were constructed to determine the complete genomic sequence of B. melitensis QY1. The annotation was performed using GeneMarkS (5), Repeat Masker (6), Tandem Repeats Finder (7), tRNAscan-SE (8), and rRNAmmer (9).
The whole-genome sequence of B. melitensis QY1 was found to be 3,311,252 bp in size and composed of two circular chromosomes, with 2,125,648 bp in chromosome I and 1,185,604 bp in chromosome II. The G+C content of this strain is 58.34%. About 86.47% (2,863,398 bp) of the nucleotide sequences are predicted to be coding sequences containing 3,559 genes, and the average gene length is 805 bp. This strain has two small RNAs (sRNAs), 55 tRNAs, and three each of 23S, 16S, and 5S rRNAs.
Functional annotation of B. melitensis QY1 genes within the GO database (performed using protein BLAST, E value, ≤1e-5) showed that 2,368 (66.5%) out of 3,559 protein-coding genes had at least some biological function assigned, with some of the genes assigned to more than one category (10).
Accession number(s).
This whole-genome sequence of B. melitensis QY1 has been deposited at DDBJ/EMBL/GenBank under the accession numbers CP022204 and CP022205, and the versions cited in this paper are CP022204.1 and CP022205.1, respectively.
ACKNOWLEDGMENTS
Xiaoan Cao, Zhizhong Jing, and Jizhang Zhou designed this project, and Xiaoan Cao and Zhaocai Li grew the isolate, purified it, and conducted DNA genomics. Xiaoan Cao analyzed the sequence, and Zhongzi Lou, Baoquan Fu, Yongsheng Liu, and Youjun Shang performed the experiments.
The study was financially supported by grants from the Ministry of Science and Technology (no. 2016YFD0500907 and 1610312017014) and by the Gansu Province Scientific and Technical Supporting Program (no. 1304NKCA162) and the Gansu Province Agricultural Biotechnology Research and Application Development Project (no. GNSW-2013-27).
Footnotes
Citation Cao X, Li Z, Lou Z, Fu B, Liu Y, Shang Y, Jing Z, Zhou J. 2017. Whole-genome sequences of Brucella melitensis strain QY1, isolated from sheep in Gansu, China. Genome Announc 5:e00896-17. https://doi.org/10.1128/genomeA.00896-17.
REFERENCES
- 1.Franco MP, Mulder M, Gilman RH, Smits HL. 2007. Human brucellosis. Lancet Infect Dis 7:775–786. doi: 10.1016/S1473-3099(07)70286-4. [DOI] [PubMed] [Google Scholar]
- 2.Mailles A, Garin-Bastuji B, Lavigne JP, Jay M, Sotto A, Maurin M, Pelloux I, O’Callaghan D, Mick V, Vaillant V, De Valk H. 2016. Human brucellosis in France in the 21st century: results from national surveillance 2004–2013. Med Mal Infect 46:411–418. doi: 10.1016/j.medmal.2016.08.007. [DOI] [PubMed] [Google Scholar]
- 3.Li YJ, Li XL, Liang S, Fang LQ, Cao WC. 2013. Epidemiological features and risk factors associated with the spatial and temporal distribution of human brucellosis in China. BMC Infect Dis 13:547. doi: 10.1186/1471-2334-13-547. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 4.Shi YJ, Lai SJ, Chen QL, Mu D, Li Y, Li XX, Yin WW, Yu HJ. 2017. Analysis on the epidemiological features of human brucellosis in northern and southern areas of China, 2015–2016. Zhonghua Liu Xing Bing Xue Za Zhi 38:435–440. (In Chinese.) [DOI] [PubMed] [Google Scholar]
- 5.Besemer J, Lomsadze A, Borodovsky M. 2001. GeneMarkS: a self-training method for prediction of gene starts in microbial genomes. Implications for finding sequence motifs in regulatory regions. Nucleic Acids Res 29:2607–2618. doi: 10.1093/nar/29.12.2607. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 6.Saha S, Bridges S, Magbanua ZV, Peterson DG. 2008. Empirical comparison of ab initio repeat finding programs. Nucleic Acids Res 36:2284–2294. doi: 10.1093/nar/gkn064. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 7.Benson G. 1999. Tandem Repeats Finder: a program to analyze DNA sequences. Nucleic Acids Res 27:573–580. doi: 10.1093/nar/27.2.573. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 8.Lowe TM, Eddy SR. 1997. tRNAscan-SE: a program for improved detection of transfer RNA genes in genomic sequence. Nucleic Acids Res 25:955–964. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 9.Lagesen K, Hallin P, Rødland EA, Staerfeldt HH, Rognes T, Ussery DW. 2007. RNAmmer: consistent and rapid annotation of ribosomal RNA genes. Nucleic Acids Res 35:3100–3108. doi: 10.1093/nar/gkm160. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 10.Ashburner M, Ball CA, Blake JA, Botstein D, Butler H, Cherry JM, Davis AP, Dolinski K, Dwight SS, Eppig JT, Harris MA, Hill DP, Issel-Tarver L, Kasarskis A, Lewis S, Matese JC, Richardson JE, Ringwald M, Rubin GM, Sherlock G. 2000. Gene ontology: tool for the unification of biology. The Gene Ontology Consortium. Nat Genet 25:25–29. doi: 10.1038/75556. [DOI] [PMC free article] [PubMed] [Google Scholar]