LETTERS

Roseomonas sp. plates containing Luria-Bertani agar. genus Roseomonas. A phylogenetic were gram-negative, plump, tree based on 16S r RNA genes (Fig- Isolated from Ticks, coccoid rods, in pairs or short chains. ure) showed that the Roseomonas sp. China Electron microscopy showed that each identifi ed in this study (representa- organism was ≈0.7 × 1.1 μm. tive strain XTD 510, GenBank acces- To the Editor: Roseomonas, The 9 isolates showed identical sion no. EU742165) was in the same which produces pink colonies, is a phenotypic and biochemical character- branch as R. cervicalis ATCC 49957 newly described genus of gram-neg- istics, which were similar to those of (GenBank accession no. AY150047). ative bacteria (1). Human infections previously reported Roseomonas spp. The new isolate was not genetically with Roseomonas spp. have been re- (1). However, the isolates required a related to R. fauriae and R. genespe- ported in the past decade, mostly in lower salt concentration (<4% NaCl) cies 6, which have been reported as immunocompromised persons with and a higher temperature (37°C instead not belonging to the genus Roseomo- underlying diseases such as acute of <35°C) for optimal growth than nas (8). The new isolate was also dis- leukemia, cancer, and rheumatoid ar- other Roseomonas spp. Antimicrobial tinct from 2 other from China, thritis (2–5). A healthy woman was re- drug susceptibility tests showed that R. lacus TH-G33 (GenBank accession ported to be infected by R. gilardii af- the isolates were susceptible to amin- no. AJ 78600), which was isolated ter being bitten by a spider (6), which oglycosides (amikacin, gentamicin, from freshwater lake sediment (9), indicated possible transmission by an and tobramycin), tetracycline, and a and Roseomonas sp. JS018 (GenBank arthropod. β-lactam (imipenem) and resistant to accession no. DQ 010108), which was As a part of an investigation of tick- cephalosporins (similar to R. cervi- isolated from soil (10). borne diseases, we collected actively calis) (1) and sulfamethoxazole. We isolated a novel Roseomonas questing and feeding ticks in Xinjiang To further characterize the sp. from adult D. nuttalli ticks and their Autonomous Region, People’s Repub- Roseomonas sp. isolated in this study, larval progeny and obtained evidence lic of China, in the summers of 2007 we amplifi ed and sequenced the 16S of transovarial transmission. Although and 2008 (7). Ticks were washed in rRNA gene. Sequences of the 9 iso- we cannot conclude that ticks are vec- 75% ethanol, 30% hydrogen peroxide, lates were identical to each other tors or reservoirs of Roseomonas spp., and sterile distilled water. Five ticks and showed 98%–99.1% similar- their roles in transmitting the bacteria of the same species, sex, and develop- ity with reported species within the deserve further study. D. nuttalli ticks mental stage were pooled and ground in 1 mL of saline. A 0.1-mL suspen- sion was placed on cysteine heart agar plates containing chocolate and 9% sheep blood (Becton Dickinson Micro- biology Systems, Cockeysville, MD, USA) and supplemented with colistin, amphotericin, lincomycin, trimetho- prim, and ampicillin. Eggs laid by en- gorged female ticks were collected and kept at room temperature. Fourteen days after hatching, lar- val ticks were processed as a batch by using the same methods described above. After 2–3 days of incubation at 37°C, pink colonies were observed in 9 cultures, 8 of which originated from engorged female Dermacentor nut- talli ticks. The other culture originated from larval ticks, the progeny of an Figure. Unrooted phylogenetic tree based on 16S rRNA gene sequences of Roseomonas engorged female D. nuttalli tick. Col- spp. Tree was constructed by using MEGA 4.0 software (www.megasoftware.net) and the onies were pinpoint, pale pink, shiny, neighbor-joining method with 1,000 bootstrap replicates. Genetic distances were calculated raised, and mucoid. The pink color of by using the Kimura 2-parameter correction at the nucleotide level. Bootstrap values >50% the colonies became pronounced when are shown. The isolate obtained in this study is shown in boldface. GenBank accession numbers of reference strains are marked after each strain name. Scale bar indicates the bacteria were transferred onto nucleotide substitutions per site.

Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 16, No. 7, July 2010 1177 LETTERS are a dominant species in the study (J. Yang, F. Tang); and Chinese National Address for correspondence: Wu-Chun area and usually parasitize a variety Human Genome Center, Beijing (Z.-T. Xin) Cao, Beijing Institute of Microbiology and of wild and domestic animals. These Epidemiology, State Key Laboratory of DOI: 10.3201/eid1607.090166 ticks often feed on humans as alterna- Pathogen and Biosecurity, 20 Dong-Da St, tive hosts. Because this Roseomonas Fengtai District, Beijing 100071, People’s References sp. is not a common pathogen, its role Republic of China; email: [email protected]. in public health and veterinary medi- 1. Rihs JD, Brenner DJ, Weaver RE, Steiger- ac.cn cine is unkown. walt AG, Hollis DG, Yu VL. Roseomonas, Phenotypic characterization of a new genus associated with bacteremia and other human infections. J Clin Micro- the isolates indicated similarities with biol. 1993;31:3275–83. previously reported Roseomonas spp. 2. Christakis GB, Perlorentzou S, Alexaki P, Phylogenetic analysis showed that the Megalakaki A, Zarkadis IK. Central line– novel Roseomonas sp. is closely relat- related bacteraemia due to in a neutropenic patient with acute ed to R. cervicalis, which was isolated myeloid leukaemia in Piraeus, Greece. J Misindentifi cation from a cancer patient. Our isolates also Med Microbiol. 2006;55:1153–6. DOI: differed from 2 reported strains iso- 10.1099/jmm.0.46634-0 of Mycobacterium lated from freshwater lake sediment in 3. De I, Rolston KV, Han XY. Clinical sig- nifi cance of Roseomonas species isolated kumamotonense Jiangsu Province, China (9) and from from catheter and blood samples: analy- as M. tuberculosis soil in Fujian Province, China (10). sis of 36 cases in patients with cancer. This result indicated the species diver- Clin Infect Dis. 2004;38:1579–84. DOI: To the Editor: Because of slow sity of the genus Roseomonas, which 10.1086/420824 4. McLean TW, Rouster-Stevens K, Woods growth of mycobacteria, use of rapid might be related to different bacterial CR, Shetty AK. Catheter-related bacte- tests to identify them is strongly rec- origins. Because of the unique bio- remia due to Roseomonas species in pe- ommended; rapid tests are widely chemical characteristics, antimicro- diatric hematology/oncology patients. Pe- used as an advanced diagnostic tool in bial drug susceptibilities, and novel diatr Blood Cancer. 2006;46:514–6. DOI: 10.1002/pbc.20339 clinical laboratories (1,2). These tests isolation source of our isolates, the 5. Sipsas NV, Papaparaskevas J, Stefanou I, are particularly useful for diagnos- pathogenesis of this organism should Kalatzis K, Vlachoyiannopoulos P, Avla- ing extrapulmonary mycobacterioses be investigated. mis A. Septic arthritis due to Roseomonas and identifying unusual mycobacteria mucosa in a rheumatoid arthritis patient receiving infl iximab therapy. Diagn Mi- as etiologic agents (3). Commercial Acknowledgment crobiol Infect Dis. 2006;55:343–5. DOI: probes are frequently used for rapid We are grateful to Xiang Y. Han for 10.1016/j.diagmicrobio.2006.01.028 and specifi c identifi cation of myco- critically reading the manuscript. 6. Shokar NK, Shokar GS, Islam J, Cass bacteria, especially Mycobacterium AR. Roseomonas gilardii infection: tuberculosis complex. However, cross- This study was supported by Nation- case report and review. J Clin Micro- biol. 2002;40:4789–91. DOI: 10.1128/ reactivity of DNA probes between al Natural Science Foundation of China JCM.40.12.4789-4791.2002 mycobacterial species could result in (grant 30600506), the National Science 7. Qiu EC, Zhang F, Liu W, Wu XM, Cao incorrect diagnosis and treatment of Fund for Distinguished Young Scholars WC. Isolation and identifi cation of patients (4,5). Misidentifi cation could (grant 30725032), and Beijing Technology Roseomonas spp. from ticks [in Chinese]. Chung Hua Wei Sheng Wu Hsueh Ho be a problem if a newly described spe- New Star (grant 2007A066). Mieh I Hsueh Tsa Chih. 2009;29:29–32. cies, such as M. kumamotonense (6), 8. Bibashi E, Sofi anou D, Kontopoulou were an etiologic agent of a disease. Wei Liu,1 Fang Zhang,1 K, Mitsopoulos E, Kokolina E. Peri- tonitis due to Roseomonas fauriae in a In July 2006, we obtained a fi ne- Er-Chen Qiu, Jun Yang, patient undergoing continuous ambula- needle, puncture aspiration biopsy Zhong-Tao Xin, Xiao-Ming tory peritoneal dialysis. J Clin Microbiol. specimen from a cervical lymph node Wu, Fang Tang, Hong Yang, 2000;38:456–7. of a 30-year-old man at Doce de Oc- and Wu-Chun Cao 9. Jiang CY, Dai X, Wang BJ, Zhou YG, Liu SJ. Roseomonas lacus sp. nov., iso- tubre Hospital (Madrid, Spain). The Author affi liations: Beijing Institute of Micro- lated from freshwater lake sediment. Int J patient was a recent immigrant from biology and Epidemiology, Beijing, People’s Syst Evol Microbiol. 2006;56:25–8. DOI: Paraguay and was HIV positive (C2 Republic of China (W. Liu, F. Zhang, E.-C. 10.1099/ijs.0.63938-0 stage of infection). A biopsy speci- 10. Jiang YJ, Deng YJ, Liu XR, Xie BG, Hu Qiu, X.-M. Wu, H. Yang, W.-C. Cao); Chi- FP. Isolation and identifi cation of a bacte- men from a cervical lymph node nese People’s Armed Police Force Center rial strain JS018 capable of degrading sev- showed necrotizing granulomatous for Disease Control and Prevention, Beijing eral kinds of organophosphate pesticides lymphadenopathy. A computed to- 1These authors contributed equally to this [in Chinese]. Wei Sheng Wu Xue Bao. mographic scan showed cervico-tho- 2006;46:463–6. article. raco-abdominal, multiple cervical,

1178 Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 16, No. 7, July 2010