[Study on Bartonella vinsonii berkhoffii isolated from blood of native dogs in China].
ABSTRACT To isolate and identify Bartonella strains from native dogs in Shandong province in China.
EDTA-anticoagulated blood samples were collected from 71 native dogs in Yanggu county of Shandong province in March 2005. All isolates were grown on brain heart infusion agar plates containing 5% defibrinated rabbit blood. The agar plates were incubated at 37 degrees C in a humidified with 5% CO2 environment for 4 weeks or longer. All Bartonella-like isolates were examined by routine Gram and Giménez staining and then followed by polymerase chain reaction (PCR) and PCR-RFLP analysis for identification and differentiation of the isolates. Sequencing 16S rRNA, citrate synthase (gltA) gene and 16S-23S rRNA ITS were carried out and sequential similarities were calculated using the DNASTAR5 software package. The phylogenetic tree was inferred from each bootstrap sample, using the neighbor-joining methods as executed in the MEGA 3.1 software. The translation from DNA to protein were determined by DNASIS 2.5.
The two Bartonella-like organisms (strains Q52SHD and Q64SHD) were isolated from the blood of 71 dogs. Light microscopic examination of the Gram and Giménez-stained micro-organisms showed small, short and slightly curved pleomorphic gram-negative bacilli. Amplified products of the three pairs of Bartonella genus-specific primers carried the same size as the predicted of those Bartonella species. Data from PCR-RFLP analysis showed that the two strains that having the same profiles were all different from the B. henselae type strain-16S rRNA, gltA and 16S-23S rRNA ITS sequences from the two isolates were 100.0%, 99.7% and 97.2% homologous to B. vinsonii berkhoffii.
Based on these findings, the two isolates Q52SHD and Q64SHD were demonstrated as B. vinsonii berkhoffii. To our knowledge, this was the first report on the presence of Bartonella infection in native dogs from China, which constituted a large reservoir of Bartonella species in this country.
SourceAvailable from: Aurélie Lajus[Show abstract] [Hide abstract]
ABSTRACT: Adaptive radiation is the rapid origination of multiple species from a single ancestor as the result of concurrent adaptation to disparate environments. This fundamental evolutionary process is considered to be responsible for the genesis of a great portion of the diversity of life. Bacteria have evolved enormous biological diversity by exploiting an exceptional range of environments, yet diversification of bacteria via adaptive radiation has been documented in a few cases only and the underlying molecular mechanisms are largely unknown. Here we show a compelling example of adaptive radiation in pathogenic bacteria and reveal their genetic basis. Our evolutionary genomic analyses of the α-proteobacterial genus Bartonella uncover two parallel adaptive radiations within these host-restricted mammalian pathogens. We identify a horizontally-acquired protein secretion system, which has evolved to target specific bacterial effector proteins into host cells as the evolutionary key innovation triggering these parallel adaptive radiations. We show that the functional versatility and adaptive potential of the VirB type IV secretion system (T4SS), and thereby translocated Bartonella effector proteins (Beps), evolved in parallel in the two lineages prior to their radiations. Independent chromosomal fixation of the virB operon and consecutive rounds of lineage-specific bep gene duplications followed by their functional diversification characterize these parallel evolutionary trajectories. Whereas most Beps maintained their ancestral domain constitution, strikingly, a novel type of effector protein emerged convergently in both lineages. This resulted in similar arrays of host cell-targeted effector proteins in the two lineages of Bartonella as the basis of their independent radiation. The parallel molecular evolution of the VirB/Bep system displays a striking example of a key innovation involved in independent adaptive processes and the emergence of bacterial pathogens. Furthermore, our study highlights the remarkable evolvability of T4SSs and their effector proteins, explaining their broad application in bacterial interactions with the environment.PLoS Genetics 02/2011; 7(2):e1001296. DOI:10.1371/journal.pgen.1001296 · 8.17 Impact Factor
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ABSTRACT: Using pre-enrichment culture in Bartonella alpha-Proteobacteria growth medium (BAPGM) followed by PCR amplification and DNA sequence identification that targeted a fragment of the citrate synthase gene (gltA), we provide evidence of common bartonella infections and diverse Bartonella species in the blood of stray dogs from Bangkok and Khon Kaen, Thailand. The overall prevalence of all Bartonella species was 31.3% (60/192), with 27.9% (31/111) and 35.8% (29/81) in the stray dogs from Bangkok and Khon Kaen, respectively. Phylogenetic analyzes of gltA identified eight species/genotypes of Bartonella in the blood of stray dogs, including B. vinsonii subsp. arupensis, B. elizabethae, B. grahamii, B. quintana, B. taylorii, and three novel genotypes (BK1, KK1 and KK2) possibly representing unique species with ≤ 90.2% similarities to any of the known Bartonella species B. vinsonii subsp. arupensis was the only species detected in dogs from both sites, B. quintana and BK1 were found in the dogs from Bangkok, B. elizabethae, B. taylorii, KK1 and KK2 were found in the dogs from Khon Kaen. We conclude that stray dogs in Thailand are frequently infected with Bartonella species that vary with geographic region. As some Bartonella species detected in the present study are considered pathogenic for humans, stray dogs in Thailand may serve as possible reservoirs for Bartonella causing human illnesses. Further work is needed to determine the role of those newly discovered Bartonella genotypes/species in human and veterinary medicine.Veterinary Microbiology 12/2010; 146(3-4):314-9. DOI:10.1016/j.vetmic.2010.05.017 · 2.73 Impact Factor
Journal of Veterinary Internal Medicine 09/2010; 24(5):1229-32. DOI:10.1111/j.1939-1676.2010.0563.x · 2.22 Impact Factor