Bartonella DNA

Mhamphi, Ginethon G., Msoffe, Venance T., Lyimo, Charles M., Katakweba, Abdul S., Massawe, Apia W., Komba, Erick V. G. & Mnyone, Ladslaus L., 2024, Detection and characterization of zoonotic Bartonella spp. in rodents and shrews ectoparasites from Kigoma and Morogoro regions, Tanzania, Mammalia (Warsaw, Poland) 88 (1), pp. 41-51 : 45

3.2 Detection of Bartonella DNA in ectoparasite pools

Bartonella DNA was amplified in 49 pools (34.8 %) out of the 141 pools of all ectoparasites. For individual types of ectoparasite pools, Bartonella DNA was detected in 25 (32.9 %) out of 76 pools of mite, 22 (40 %) out of 55 pools of flea species, 1 (12.5 %) out of eight pools of ticks and 1 (50 %) out of two pools of lice (Table 2). Among the habitat variables, the farm habitat detected 39.6 % slightly higher than 33.3 % of the indoor habitat. The natural habitat detected 22.2 % and the peridomestic habitat detected 7.1 %. Statistically, there were significant differences in the prevalence of Bartonella DNA among two variables, namely habitats (χ 2 = 8.589, df = 3, p = 0.035) and ectoparasites species (χ 2 = 16.5646, df = 7, p = 0.0243).

3.3 Phylogenetic analysis of gltA sequences

Out of 49 Bartonella DNA confirmed by sequencing, 22 sequences were recovered, however, only 16 consensus sequences were successfully assembled. After being submitted to BLAST in the NCBI database, seven sequences; five from mites’ pools and two from fleas’ pools showed low similarities (75–85 %) when compared to other Bartonella spp. in the GenBank database. Therefore, only nine DNA sequences were submitted and accepted to the GenBank database (NCBI) with accession numbers (OQ382888-OQ382892 and OQ504174-OQ504177). The phylogenetic tree of the Bartonella sequences and the previous identified Bartonella genotypes retrieved from the NCBI GeneBank were used to evaluate the evolutionary relationship ( Figure 4 ). Based on the maximum likelihood phylogeny and reference sequences of the gltA Bartonella gene obtained from the GenBank database; phylogenetic analysis identified one B. elizabethae (accession number OQ504174) from Xenopsylla brasiliensis with 98.71 % similar to previously identified B. elizabethae from Thailand with accession number JX158353.1. Bartonella sp. , with accession number OQ 504177 in this study, is phylogenetically related to B. tribocorum with accession number OP382454.1 previously identified from China. Five genotypes with accession numbers OQ382891; OQ382888; OQ382889; OQ382890 and OQ382892 from flea species ( Dinopsylla lypusus , and Ctenophthalmus calceatus ) were closely related to Ugandan and Kenyan Bartonella spp. with accession numbers JX428746.1, MF443361.1, and KM233491.1 with more than 99 % identity from blasting. Phylogenetically, Ugandan and Kenyan Bartonella genotypes were closely related to the South African Bartonella genotypes with GeneBank accession number AJ583114.1 as described in Figure 4 . Bartonella genotype from lice (OQ504175) phylogenetically is related to JX428760.1 from Uganda and is closely related to genotype FJ686050.1 from Israel with 98.89 % similarity to Bartonella elizabathae with accession number LR134527.1 from the GenBank database. Bartonella genotype (OQ504176) from Haemophisalis tick detected in this study showed 98.94 % similarity to Bartonella strain with accession number AJ583115.1 from South Africa. Furthermore, the Medianjoining network ( Figure 5 ) showed five clades, among them four clades form different clusters, with different lineages and unique haplotypes. Five genotypes related to Bartonella spp. discovered in Ugandan, Kenyan and South African Bartonella spp. formed one haplogroup/clade, different lineages with independent haplotypes.

Figures

Figure 4: Phylogenetic tree showing the relatedness of the Bartonella gltA gene sequences detected from rodents and shrews ectoparasites; fleas (FTZ), lice (LTZ), and ticks (TTZ) along with reference sequences from the GenBank database. The phylogenetic tree was constructed using the maximum likelihood method. The tree with the highest log likelihood (−1773.15) is shown. Evolutionary analyses were conducted in MEGA 11 (2021). The detected Bartonella genotypes and their sources in this study are indicated by nodes of different colors.

Figure 5: Median-joining network showing the evolutionary relationships and likely ancestral networks among Bartonella haplotypes based on the 379-bp sequence of gltA gene from fleas (FTZ), ticks (TTZ), and lice (LTZ) hosts.