A single Leptospira strain (designated Bejo-Iso9(T)) was isolated from a soil sample taken in Johor, Malaysia. The isolate showed motility and morphology typical of the genus Leptospira under dark-field microscopy. Cells were found to be 10–13 um in length and 0.2 um in diameter, with a wavelength of 0.5 um and an amplitude of approximately 0.2 um. Phenotypically, strain Bejo-Iso9(T) grew in Ellinghausen-McCullough-Johnson-Harris medium at 13, 30 and 37 degrees C, and also in the presence of 8-azaguanine. Serologically, strain Bejo-Iso9(T) produced titres towards several members of the Tarassovi serogroup, but was found to be serologically unique by cross-agglutinin absorption test and thus represented a novel serovar. The proposed name for this serovar is Malaysia. Phylogenetic analysis of 16S rRNA gene sequences placed this novel strain within the radiation of the genus Leptospira, with sequence similarities within the range 90.4–99.5% with respect to recognized Leptospira species. DNA-DNA hybridization against the three most closely related Leptospira species was used to confirm the results of the 16S rRNA gene sequence analysis. The G+C content of the genome of strain Bejo-Iso9(T) was 36.2 mol%. On the basis of phenotypic, serological and phylogenetic data, strain Bejo-Iso9(T) represents a novel species of the genus Leptospira, for which the name Leptospira kmetyi sp. nov. is proposed. The type strain is Bejo-Iso9(T) (=WHO LT1101(T)=KIT Bejo-Iso9(T)).
* Slack AT, Khairani-Bejo S, Symonds ML, Dohnt MF, Galloway RL, Steigerwalt AG, Bahaman AR, Craig S, Harrower BJ, Smythe LD. Leptospira kmetyi sp. nov., isolated from an environmental source in Malaysia. Int J Syst Evol Microbiol 59, 2009, 705–8
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;
* 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.