L. wolffii

Abstract:

A single Leptospira strain (designated Khorat-H2(T)) was isolated from the urine of an adult male patient with suspected leptospirosis from the province of Nakornrachasima, Thailand. The isolate showed typical Leptospira motility and morphology under dark-field microscopy. Cells were 10–13 um long and 0.2 um in diameter, with a wavelength of 0.5 um and an amplitude of approximately 0.3 um. Phenotypically, strain Khorat-H2(T) did not grow at 13 degrees C but grew at 30 and 37 degrees C and in the presence of 8-azaguanine. Serological identification using the microscopic agglutination test revealed that strain Khorat-H2(T) had no cross-reaction with any recognized Leptospira serogroups. Phylogenetic analysis of the 16S rRNA gene sequence placed the novel strain within the radiation of the genus Leptospira, with sequence similarities of 88.1-97.7 % to recognized Leptospira species. DNA-DNA hybridization against the type strains of the three most closely related Leptospira species was used to confirm the results of the 16S rRNA sequence analysis. The G+C content of strain Khorat-H2(T) was 41.8 mol%. On the basis of phenotypic, serological and phylogenetic data, strain Khorat-H2(T) represents a novel species of the genus Leptospira, for which the name Leptospira wolffii sp. nov. is proposed. The type strain is Khorat-H2(T) (=WHO LT1686(T) =KIT Khorat-H2(T)).

* Slack AT, Kalambaheti T, Symonds ML, Dohnt MF, Galloway RL, Steigerwalt AG, Chaicumpa W, Bunyaraksyotin G, Craig S, Harrower BJ, Smythe LD. Leptospira wolffii sp. nov., isolated from a human with suspected leptospirosis in Thailand. Int J Syst Evol Microbiol 58, 2008, 2305–8
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Conventionally, Leptospira were separated into two valid species, Leptospira interrogans for pathogenic leptospires and Leptospira biflexa for saprophytic ones (Brenner et al., 1999).
Current Leptospira speciation is based on DNA heterogeneity as determined by hybridization experiments.
The first of such studies was by Yasuda et al., 1987 followed by Ramadass et al., 1992.
The most complete study, also summarizing the observation of the previous two studies is by Brenner et al., 1999. Brenner and co-workers described 17 DNA hybridization groups (species), representing the 12 previously describes species and five new ‘genomospecies’, including Leptospira alexanderi.
Smythe et al., 2012 re-named the four remaining ‘genomospecies’ 1, 3, 4 and 5 later on to Leptospira alstonii, L. vanthielii , L. terpstrae and L. yanagawae, respectively.
To date, speciation is increasingly based on other molecular techniques, mainly DNA sequences of the rrs gene or multilocus sequence genotyping, which likely will completely replace the DNA hybridization method.

* Yasuda PH, Steigerwalt AG, Sulzer KR, Kaufmann AF, Rogers F, Brenner DJ. Deoxyribonucleic acid relatedness between serogroups and serovars in the family Leptospiroceae with proposals for seven Leptospira species. Int J Syst Bacteriol 1987, 37, 407-415

* Ramadass P, Jarvis BDW, Corner RJ, Penny D, Marshall RB. Genetic characterization of pathogenic Leptospira species by DNA hybridization. Int J Syst Bacteriol 1992, 42, 215-219

* Brenner DJ, Kaufmann AF, Sulzer KR, Steigerwalt AG, Rogers F, Weyant RS. Further determination of DNA relatedness between serogroups and serovars in the family Leptospiroceae with a proposal for Leptospira alexanderi sp. nov. and four new Leptospira genomospecies. Int J Syst Bacteriol 1999, 49, 839-858

* Smythe L, Adler B, Hartskeerl RA, Galloway RL, Turenne CY, Levett PN. Classification of Leptospira genomospecies 1, genomospecies 3, genomospecies 4 and genomospecies 5 as Leptospira alstonii sp. nov., Leptospira vanthielii sp. nov., Leptospira terpstrae sp. nov., Leptospira yanagawae sp. nov., respectively. Int J Syst Evol Microbiol 2012;

Recommended literature

* Ahmed A, Grobusch MP, Klatser P, Hartskeerl RA. Molecular Approaches in the Detection and Characterization of Leptospira. J Bacteriol Parasitol 2012, 3:2 http://dx.doi.org/10.4172/2155-9597.1000133

* Adler, B., & de la Peña Moctezuma, A. (2010). Leptospira and leptospirosis. Veterinary microbiology 140, 287-296.

* Cerqueira, G.M. & Picardeau, M. (2009). A century of Leptospira strain typing. Infection, Genetics and Evolution 9, 760-768.