Leishmania (Viannia) lainsoni occupies a unique niche within the subgenus Viannia

Abstract

Leishmania lainsoni has recently been recognized as a new peripylarian species belonging to the subgenus Viannia and the L. braziliensis complex. It has been isolated from its sandfly vector, reservoir host and cutaneous lesions of human patients. Microscopical examination has shown characteristics which are different from those of other members of the L. braziliensis complex. Nuclear deoxyribonucleic acid (DNA) hybridization patterns with a beta tubulin probe and kinetoplast DNA buoyant density measurements show close similarities with other species of the L. braziliensis complex. However, kinetoplast DNA restriction enzyme fragment patterns of L. (V.) lainsoni isolates show similarities to L. mexicana complex species as well as weak cross hybridization. L. (V.) lainsoni is also amplified with L. braziliensis complex specific polymerase chain reaction (PCR) primers but it requires a lower annealing temperature and gives a 300 base pair PCR product. A possible model for the binding of PCR primers to the L. (V.) lainsoni kinetoplast DNA minicircle is proposed.

Leishmania (Viannia) lainsoni (Kinetoplastida: Trypanosomatidae), a divergent Leishmania of the Viannia subgenus: a mini review

“…On the other hand, amplification of kDNA from species from the Viannia subgenus usually generates a product of 750 base pairs. Thus, these data show that L. (Viannia) lainsoni is an isolated species inside the Viannia subgenus (Eresh et al 1995).…”

“…Although the Leishmania species grouped in the Viannia subgenus presented very similar banding profiles, L. (Viannia) lainsoni presented a profile more similar to L. (Leishmania) amazonensis, a typical representative of the Leishmania subgenus (Eresh et al 1995). However, hybridization of L. (Viannia) lainsoni nuclear DNA with a β-tubulin probe, followed by measurement of the kDNA density, suggested a molecular proximity between L. (Viannia) lainsoni and Leishmania species belonging to the L. (Viannia) braziliensis species complex (Eresh et al 1995).…”

“…Sequencing of the minicircle kDNA from L. (Viannia) lainsoni was performed (McCann et al 1999), in an attempt to explain the small fragment (300 base pairs) previously observed during the amplification of this DNA with universal Viannia primers (Eresh et al 1995). The results showed the existence in minicircles of L. (Viannia) lainsoni kDNA of specific sequences.…”

“…Members from the Leishmania subgenus grow at the pyloric and midgut regions (suprapylarian development), while Viannia species grow at the hindgut region (peripylarian development) (Lainson & Shaw 1979 , Eresh et al 1995, Fernandes et al 1995, McCann et al 1999), but the available data are still not sufficient for an unequivocal taxonomic placement of this species. Characteristic features of L. (Viannia) lainsoni are its exuberant amastigote growth in skin lesions and the easy of cultivation in simple axenic culture media, which are typical of parasites belonging to the Leishmania subgenus.…”

Genetic Data Showing Evolutionary Links between Leishmania and Endotrypanum

“…schaudinni and other Leishmania species. Leishmania (V.) lainsoni represents a very divergent monophyletic Viannia species, which was clustered as an independent complex (Thomaz-Soccol et al 1993, Cupolillo et al 1994, Fernandes et al 1995, Eresh et al 1995. The internal transcribed spacers of the rRNA gene were amplified by PCR and the product digested with several restriction enzymes (Cupolillo et al 1995).…”