Bartonella spp. infections are often chronic or asymp- tomatic in their reservoir hosts. Bacteria have been shown to infect erythrocytes, endothelial cells, macro- phages and even human stem cells [8–17]. The infection of erythroctyes is host-specific and mediated by the so- called “Trw”-type 4 secretion system which facilitates host-restricted adhesion to erythrocytes . Localized tissue manifestations may occur in reservoir and inci- dental hosts and the growth of bacteria in vascular tissue can lead to angioproliferative tumors and inflammation [5, 6, 12, 19]. The ability of Bartonella spp. to persist within immunoprivileged intracellular habitats is prob- ably a key factor contributing to the establishment of chronic infections; however, the cyclic release of bacteria to the blood stream or the hemolytic activity of some species can also result in dramatic illnesses such as trench fever or Oroya fever, respectively . The pres- ence of Bartonella spp. in the blood stream of infected hosts or within the erythrocytes also facilitates their transfer via ingestion along with the blood meal of arthropod vectors [5, 21].
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A recent study revealed that the most common tick species found on cats in the UK were (in decreasing order of prevalence) Ixodes ricinus, Ixodes hexagonus and Ixodes trianguliceps, with an overall prevalence of tick attachment on cats of 6.6% . A similar study of ticks found on dogs in the UK revealed the presence of I. ricinus and I. hexagonus, but Ixodes canisuga, Haema- physalis punctata and Dermacentor reticulatus were also reported, together with a much higher prevalence (30%) of tick infestation on dogs . In line with the lower prevalence of tick infestation in cats compared to dogs, it is also thought that transmission of tick-borne patho- gens is likely to be less common in cats than in dogs, although there is a lack of publications in this field . Possible explanations for the species discrepancies are: differences in lifestyle, behaviour (e.g. increased self- grooming in cats compared to dogs) and in immunity to tick-borne infections . Nevertheless, tick-borne patho- gens are reported in cats and can be problematic; the pathogen species reported include Babesia spp., Hepato- zoon spp., Borrelia spp., Ehrlichia spp., Anaplasma spp., haemoplasma species and Bartonella spp. .
As expected, a high B. henselae seroprevalence was found in this veterinary worker population (37.1%). This Bartonella has a worldwide distribution, cats are the main reservoirs and vectors, and fleas (Ctenocephalides felis and C. canis) are considered the primary arthropod vectors for infecting cats and other animals. B. henselae is the primary or sole causative agent of CSD and in- duces other clinical syndromes in humans . Docu- mentation of human Bartonella infections is scarce in Spain. Nevertheless, clinical descriptions [5, 17, 26] and seroepidemiological studies about the prevalence of B. henselae/B. quintana [27 – 29] have been reported. In our previous studies carried out in La Rioja (North of Spain), B. henselae seroprevalences in cat owners, HIV-infected patients and blood donors were 28.9%, 17.3% and 5.9%, respectively, using a commercial kit [30, 31]. These lower percentages most likely reflect differences in the antigens used for testing, and exposure risks among the study populations, with veterinary personnel, most likely having the highest exposure risk. As previously reported, serological tests may not reliably distinguish between antibody responses to Bartonella spp. moreover, other infectious agents . Contact with cats and their fleas are the main epidemiological risk factors that contribute to acquiring B. henselae infection, and this species has also been involved in disease in dogs from Spain . In a molecular study carried out in fleas from La Rioja, 3.4% and 6.8% C. felis were infected with B. henselae and B. clarridgeiae, respectively . Importantly, cats and dogs are frequently infested with numerous fleas, rather than a single or few fleas. Both B. henselae and B. clar- ridgeiae have been isolated from healthy human blood donors in Brazil [9, 34]. To our knowledge, no studies have attempted to culture Bartonella from the blood of healthy humans in Spain. Although a study from the United States found a statistical association between Bartonella spp. bacteremia and symptomatology , that study, the study presented here, and the Brazilian blood donor study indicate that B. henselae bacteremia can be documented in asymptomatic individuals. Table 4 IFA serological results for bacteremic veterinary personnel that were Bartonella-positive by BAPGM enrichment PCR testing
Bartonella sp. 4 (MF580655) is very similar (99.7%) to Bartonella sp. isolates collected from Japanese sika deer (AB703146, see Fig. 1) and in our phylogenetic analyses these isolates are associated with other Bartonella sp. isolates from Japanese sika deer and formed a distinct clade with Bartonella spp. isolated from Japanese sika deer. Probably “japanese” Bartonella isolates were intro- ducted to Poland. This observation suggests that the strain of Bartonella sp. bacteria identified in the present study is derived from Japanese sika deer introduced to Europe by vectors to environment, indicating that this Asian strains could be spread by L. cervi to European red deer (Cervus elaphus).
Recent research has demonstrated the utility of ENM to predict disease in distant novel areas (8), but it remains rare for these predictive models to be validated using independent data, which is particularly true for models of pathogens in wildlife. We tackle this problem using a unique dataset of two pathogens, Toxoplasma gondii and Bartonella spp., isolated from wild felids across North America. Specifically, we analyzed samples from bobcats (Lynx rufus) and puma (Puma concolor), two secre- tive carnivores that are widespread in North America and are adaptable to a wide array of habitats where they are exposed to pathogens acquired from their environment (10–12). T. gondii is an intracellular protozoan parasite found in warm-blooded animals, including birds and mammals, and is transmitted via consumption of sporulated oocysts in feces, water, and soil or bradyzoites in tissues of prey species (13); in these wild felids, T. gondii is likely transmitted via consumption of infected prey such as rodents, lagomorphs, and cervids (10). The Bartonella genus includes gram negative anaerobic facultative intracellular bacteria species that cause an array of diseases affecting mam- mals; contact with arthropod vectors, particularly fleas, is the primary route of transmission of Bartonella henselae, Bartonella koehlerae, and Bartonella clarridgeiae (hereafter Bartonella spp.) (14, 15). Both, T. gondii and Bartonella spp., require other organ- isms to persist; thus, here we define them as micro-parasites or simply parasites (7).
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Results: The following prevalences were detected: Babesia spp.: 0.4% (n = 17, including one pool of two larvae) in 2009 and 0.5 to 0.7% (n = 11, including one pool of five larvae) in 2010; Rickettsia spp.: 6.4 to 7.7% (n = 285, including 16 pools of 76 larvae) in 2009. DNA of Bartonella spp. in I. ricinus in Bavarian public parks could not be identified. Sequence analysis revealed the following species: Babesia sp. EU1 (n = 25), B. divergens (n = 1), B. divergens/capreoli (n = 1), B. gibsoni-like (n = 1), R. helvetica (n = 272), R. monacensis IrR/Munich (n = 12) and unspecified R. monacensis (n = 1). The majority of coinfections were R. helvetica with A. phagocytophilum (n = 27), but coinfections between Babesia spp. and A. phagocytophilum, or Babesia spp. and R. helvetica were also detected. Conclusions: I. ricinus ticks in urban areas of Germany harbor several tick-borne pathogens and coinfections were also observed. Public parks are of particularly great interest regarding the epidemiology of tick-borne pathogens, because of differences in both the prevalence of pathogens in ticks as well as a varying species arrangement when compared to woodland areas. The record of DNA of a Babesia gibsoni-like pathogen detected in I. ricinus suggests that I. ricinus may harbor and transmit more Babesia spp. than previously known. Because of their high recreational value for human beings, urban green areas are likely to remain in the research focus on public health issues.
test included negative (water) and positive controls con- taining the DNA of B. afzelii, B. garini, B. henselae, C. bur- netii Henzerling strain and Rickettsia conori H24 strain, all from the collection of the National Institute of Pub- lic Heath – National Institute of Hygiene. For B. burg- dorferi and Rickettsia spp. the cycling conditions were as follows: 3 min at 95°C, followed by 40 cycles of 1 min denaturation at 95°C, annealing for 1 min at 55°C, elon- gation for 1 min at 72°C and final elongation for 7 min at 95°C. For Bartonella spp. the cycling conditions were as follows: 10 min at 94°C, followed by 45 cycles of 1 min at 94°C, 1 min at 57°C, 2 min at 72°C and finally 10 min at 72°C. For C. burnetii the cycling conditions were as fol- lows: 3 min at 95°C, followed by 40 cycles of 1 min at 95°C, 1 min at 57°C, 1 min at 72°C, and finally 7 min at 95°C. Polymerase chain reactions were performed in a Master- cycler EP Gradient PCR/thermal cycler (Eppendorf AG, Hamburg, Germany).
Bartonella spp. are emerging pathogens, as new Bartonella species have been identified in humans and a wide range of mammals in recent years (5, 17, 18, 20–23, 27, 28; B. B. Chomel, R. W. Kasten, C. C. Chang, K. Yamamoto, R. Heller, S. Maruyama, H. Ueno, D. Simpson, S. S. Swift, Y. Piemont, and N. C. Pedersen, Abstr. Int. Conf. Emerg. Infect. Dis., p. 21.10, 1998; R. Heller, M. Kubina, G. Delacour, I. Mahoudeau, F. Lamarque, M. Artois, H. Monteil, B. Jaulhac, and Y. Pi- emont, Abstr. 97th Gen. Meet. Am. Soc. Microbiol., abstr. B-505, p. 115, 1997; R. Heller, M. Kubina, G. Delacour, F. Lamarque, G. Van Laere, R. Kasten, B. Chomel, and Y. Pi- emont, Abstr. Int. Conf. Emerg. Infect. Dis., p. 21.18, 1998). Several Bartonella species and subspecies are important human pathogens that cause a variety of clinical syndromes, and most Bartonella organisms are arthropod borne. Bartonella bacilli- formis is the agent of Carrio´n’s disease, which is mainly found in the Andes mountains, and is transmitted by sand flies (3). B. bacilliformis infection is characterized by a biphasic process. The acute form of the infection, Oroya fever, causes severe and life-threatening hemolytic anemia, and the chronic form, ver- ruga peruana, results in vascular proliferative lesions of the skin (12). B. quintana, the agent of trench fever, is transmitted by the human body louse (36). B. quintana was also identified as one of two agents causing bacillary angiomatosis (26). In urban centers, human cases of this infection were recently observed in homeless people and alcohol abusers. Cat scratch disease (CSD), caused by B. henselae, is an important zoonosis with cats serving as the major reservoir (25) and cat fleas (Ctenocephalides felis) as the vector (16). Although CSD is
Isolation and identification of Bartonella. Three blood cul- tures for aerobic and anaerobic bacteria failed to grow bacte- ria. However, blood collected from the dog at the same time and cultured from the frozen-thawed EDTA tube grew a non- hemolytic gram-negative organism after 8 days, with only a few (seven), small (0.5 to 1 mm) white colonies. The colony growth characteristics and morphology were suggestive of Bartonella spp., based on time to appear, size, and color. Microscopic examination demonstrated elongated, slightly curved, gram- negative rods. PCR amplification with gltA primers produced a 400-bp fragment strongly suggestive of Bartonella. Digestion
be low to moderate in Europe . In previous Euro- pean studies, Bartonella spp. were reported with high prevalences (16–70.6%) in Apodemus and Myodes from Sweden, Germany and Poland [6, 34, 35]. The preva- lences for both rodent genera fall in line with findings from the present study. The prevalence in M. glareolus is expected to be lower because bank voles are known to have an immune-mediated clearance of the infec- tion within a few months . This is why it is not surprising that the prevalence in M. glareolus was sig- nificantly lower than in Apodemus and Microtus in the present study. Thus far, prevalences in Microtus voles from Poland and Austria have ranged between 14–18%; however, only a low number of individuals were tested [7, 9]. In the present study, a very high prevalence (74.7%) was detected in Microtus spp. which is line with recent studies from Poland and Spain (47–66.8%) [36, 37]. Individuals belonging to the genus Microtus were thus far not examined for immunity or the abil- ity to resolve Bartonella infections. However, regard- ing the prevalence from the present study it seems highly unlikely that they have the ability to resolve an infection with Bartonella or the duration of resolving the infections seems rather long. The Bartonella spe- cies found in this study were likewise present in small mammals from a former study on small mammals . Most Bartonella-positive samples yielded similarity to uncultured Bartonella spp. with unknown pathogenic- ity. This observation is in line with previous findings in other small mammals from Germany . In our study, the species variety of Bartonella spp. was higher in rodents than in shrews. However, B. taylorii was found in all examined small mammal genera. This Bartonella species is known to be strongly associated with rodent hosts and fleas adapted to rodents such as Ctenophthal- mus nobilis . Closely related B. taylorii-associated strains which form in a cluster were found earlier in Sorex shrews from Sweden . Additionally, a moder- ate prevalence (14.5%) for these B. taylorii-associated strains was detected in S. araneus from the UK . Our study supports this hypothesis of host-specificity of B. taylorii-strains adapted to Sorex spp. as the col- lected specimens were solely positive for B. taylorii. Bartonella grahamii is the only Bartonella species of proven human-pathogenicity  found in rodents from the present study. Although only a small num- ber of Microtus spp. originated in Germany, B. doshiae could exclusively be detected in these individuals, hint- ing that B. doshiae may have a rather focal distribution pattern in comparison to all other Bartonella species which were detected likewise in voles of both exam- ined countries. Sex and age could not be confirmed as significant demographic factors determining individual
During the last decade, studies with dogs have provided evidence that B. vinsonii subsp. berkhoffii can cause endocar- ditis (2, 3), granulomatous lymphadenitis, and granulomatous rhinitis (21). In contrast, B. henselae DNA has been amplified and sequenced from only one dog that died of peliosis hepatis (16). To date, B. henselae is the only Bartonella sp. that has been implicated as a cause of peliosis hepatis in dogs (16) and in humans (17). In 1993, Breitschwerdt et al. isolated a novel Bartonella species, eventually named B. vinsonii subspecies berkoffii, from the blood of a dog with vegetative valvular endocarditis (3, 18). Subsequently, B. vinsonii subsp. berkoffii DNA was amplified and sequenced from blood and/or heart valves of three additional dogs with endocarditis (2). Epidemi- ologic evidence suggested tick exposure as a risk factor for Bartonella infection in dogs (22). Recently, 5 of 18 dogs (28%) with endocarditis, including three dogs infected with B. vinsonii subsp. berkoffii, examined at the Veterinary Medicine Teaching Hospital, University of California, Davis, were seroreactive to Bartonella spp. antigens and PCR positive for Bartonella spp. (B. Chomel, Abstr. Second Workshop on Comparative Medi- cine, Lyon, France, p. 61, 2001). These results prompted a study of archived cardiac valves from U.S. Army working dogs, which led to the addition of six more PCR-positive cases of B. vinsonii subsp. berkoffii to the literature (B. Chomel, Abstr. Second Workshop on Comparative Medicine, Lyon, France). Most recently, B. clarridgeiae, which was first described after its isolation from a cat in 1995, was amplified and sequenced from the heart valve of a young Boxer dog with vegetative endocar- ditis at the University of California, Davis (6).
Although cats are considered the primary reservoir host, B. henselae DNA has been PCR amplified from cows, dogs, horses, feral swine, marine mammals, and sea turtles (4, 12). Similarly, although cat fleas (Ctenocephalides felis) are considered the pri- mary vector for transmission to reservoir and potentially nonres- ervoir hosts, such as dogs and humans, B. henselae DNA has also been amplified from Ixodes ticks (24), woodlouse hunter spiders (25), and most recently tropical rat mites (26). Based upon the dog’s medical history, flea infestation while on vacation was the presumed source of infection. Assuming this mode of transmis- sion, exposure to fleas resulted in a persistent B. henselae infection that precipitated a diagnostically challenging disease process, two major surgical interventions, substantial medical care, a long-du- ration antibiotic regimen, and medical and surgical costs in excess of $15,000. Historically, C. felis was considered a relatively benign ectoparasite that induced itching and flea allergy dermatitis in dogs and was responsible for intestinal Dipylidium caninum infec- tions. An emerging paradigm indicates that C. felis and other ar- thropod vectors are responsible for the transmission of several Bartonella spp. to animals and humans throughout much of the world (4, 27). Therefore, it is important for physicians and veter-
were collected in the Estación Experimental Fátima (ESPOCH), Cantón Puyo, in Pastaza Province (01°24’34.6”S; 77°59’57.5”W), and 27 specimens (all P. irritans) were collected in Cantón Guamote, in Chimborazo Province (02°00’25.0”S; 78°47’09.3”W). The study areas had alti- tudes of 1,034 m and 3,657 m, respectively. After iden- tification at the species level, samples were kept in 70% ethanol at room temperature before being tested. DNA of each arthropod was extracted by lysis with 0.7 M ammonium hydroxide and tested by PCR with the universal primers fD1 and rp2 . This primer pair amplifies the main part of the 16S rRNA gene and has been used for the identification of Y. pestis as the causative agent of plague in India . Samples were also screened for the presence of Rickettsia spp. with PCR assays targeting rickettsial citrate synthase (gltA) and 17 kDa antigen (htrA) genes [10,11]. In accordance with the taxonomic scheme , additional rickettsial genes (ompB, sca4 and ompA) were tested to properly identify Rickettsia-positive specimens [13-17]. More- over, Bartonella spp. was tested using RNA polymerase β-subunit–encoding gene (rpoB), gltA and intergenic spacer region gene (ITS) PCR primers, which amplify fragments of Bartonella genes [18-20].
In this work, no cat had evidence of FeLV infection and FIV infection was not correlated to infection with Bartonella spe- cies; this latter point is in accordance with the results formerly published by Chomel et al. (6). In fact, stray cats usually die before becoming immunocompromised because their life span is about 4 to 5 years and the asymptomatic period of FIV infection is about 3 to 5 years (25). In contrast to FIV infection, which is more frequently observed in males because it is pref- erentially transmitted by bites or scratches during fights (9), Bartonella sp. infection did not appear to be associated with the sex of the cats. This suggests that Bartonella spp. and FIV have distinct transmission routes and that scratches and bites are not the preferential means of transmission of Bartonella infec- tion. Intercat transmission of B. henselae is therefore more likely to occur by another route, such as via cat fleas (7).
In this report, 22.8% of the samples tested positive for Bartonella spp. via PCR amplification of the 16S rRNA subunit. This molecular test has a sensitivity and speci- ficity of 100% . Genetic sequencing confirmed that the genome of all the positive samples belonged to B. bacilliformis. However, 77.2% of the samples that were interpreted as positive with a peripheral blood smear, were negative with PCR. Furthermore, authors reported a sensitivity of 36% during an outbreak in Urubamba in 1998  and a sensitivity of 24% in Ancash . On the other hand, the samples positive for B. bacilliformis were unable to grow in selective culture mediums. This could be explained due to the complex nutritional requirement and the high risk of contamination associated to this pro- cedure attributing to its reported low sensitivity .
Bartonella spp. are typical examples for vector-borne pathogens. These Gram-negative, facultative intracellular bacteria cause long-lasting intraerythrocytic infections in their respective reservoir hosts and are usually transmit- ted by blood sucking arthropods [13–15]. For example, rodents and bats serve as primary reservoirs for various Bartonella spp., including species with medical relevance for humans [16, 17]. Today, Bartonella henselae is the most common pathogenic representative of the genus Bartonella. Its reservoir host is the cat from which it is transmitted to humans (causing cat-scratch disease and other diseases) and dogs (causing endocarditis, fever of unknown origin and peliosis hepatis) [13, 18–20]. Barto- nella schoenbuchensis was isolated first from the blood of wild roe deer in 1999  and it turned out that sev- eral ruminant species serve as a reservoir hosts for this particular pathogen [22–29]. In animal reservoir hosts, asymptomatic infections with Bartonella spp. are common, although their pathogenicity remains unclear [30, 31]. Bartonella schoenbuchensis has been suggested to cause deer ked dermatitis in humans  and was isolated from a patient with a history of tick bites who suffered from fatigue, muscle pain and fever . Cur- rently, at least 37 Bartonella spp. are known to infect humans and animals .
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Several laboratories have participated in research efforts with the goal of creating an isolation medium that will enhance the growth and maintenance of Bartonella species. Despite these efforts, isolation of Bartonella species from nonimmuno- compromised individuals remains a highly insensitive diagnos- tic method. This finding suggests that additional optimization of the biochemical constituents of a liquid medium is required in order to obtain isolates from patients. To date, no liquid- or solid-phase medium has proven to be reliable for the isolation of single or multiple Bartonella species from naturally infected animals or humans (3, 13). Although some blood-free media have shown good potential for the growth of B. henselae or B. quintana (13, 49), supplementation with blood, erythrocyte membranes, or an erythrocyte membrane component seems to be required for initial growth and to achieve the full growth- promoting effect of the culture medium (33, 46). In addition, the use of hemin as a blood or erythrocyte substitute repre- sents a real challenge, which could compromise the use of these media when the infecting Bartonella species is not known or when polymicrobial Bartonella infection is present in the patient. Research has shown that optimal hemin concentra- tions differ among Bartonella species (46). Bartonella quintana required a hemin concentration of 40 g/ml for growth, while B. henselae required approximately 250 g/ml of hemin for ideal growth. In fact, hemin concentrations in excess of these established for optimal growth became toxic to each Bartonella species tested, resulting in decreased growth (i.e., ideal hemin concentrations for the growth of B. henselae are toxic to B. quintana) (46). It should be noted that only B. henselae (from culture and clinical samples) and B. quintana (from culture samples) have been evaluated in order to establish the poten- tial isolation and growth support/enhancement role of blood- free media (13, 46, 49). Also, the development of optimal cul- ture techniques and improvements in isolation media may have
Bacteriological examination of abattoir site at Mami market in Abakpa, Enugu State of Nigeria was carried out. Samples from table, dung, knife, skin and carcass were collected with the aid of a sterile swab stick. Total of 50 samples were examined for bacterial isolates using spread plate method on nutrient agar and MacConky agar. After 24h of incubation at 37 o C, the isolation frequency showed that Staphylococcus spp, Escherichia spp and Bacillus spp were more frequently isolated, followed by Pseudomonas spp. The isolates obtained from the results had an average of 147cfu for Table, 165cfu for Dung, 92cfu for Knife, 89cfu for Carcass and 148cfu for skin. Proper hygiene and management in our abattoir is highly recommended in order to prevent bacterial contamination.
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Present study represents an attempt to isolate grape rhizosphere microflora from soil samples of two different regions of Nasik district. Plant growth promoting rhizospheric microorganisms such as Azotobacter spp and Pseudomonas spp, Phosphate solubilizing fungi Aspergillus spp and Trichoderma spp. were isolated from different grape growing They were screened for their biochemial traits like Indole (IAA) production. Biochemical characterization were done using IMViC test, Gram staining, Catalase test and Urease test and others. Both Azotobacter spp and Pseudomonas spp is IAA producer and both are Gram – ve in nature. Both Azotobacter spp and Pseudomonas spp possesses Urease production capability and both of them can help to plants for urea utilization. In morphological studies using light microscope shows that both Azotobacter spp and Pseudomonas spp are immotile in nature and morphological studies of fungi revels that Aspergillus spp are black and brown spore forming while Trichoderma spp are dark green spores and thread like structure. Molecular characterization reveals the strong presence of Azotobacter venelandii as reveled by 16s rDNA analysis. Further detail molecular studies of grape rhizosphere are required to understand rhizospheric plant growth promoting bacteria and their specific roles.
This study reports the development of species-specific PCR assays for the differentiation of B. bacilliformis, B. clarridgeiae, B. henselae, and B. quintana based on sequence information for genes encoding enzymes involved in riboflavin synthesis. The riboflavin synthesis genes were chosen because they are, due to their evolutionary conservation and their absence in humans (3), excellent targets for the diagnosis of invasive pathogens. Their usefulness is further supported by the fact that the ge- netic organization of riboflavin synthesis genes differs remark- ably among bacterial species, which increases the specificity of PCR-based techniques. The ribC gene was isolated from B. henselae, and the functional complementation of a ribC-defi- cient mutant of E. coli confirmed that the encoded protein has the activity of riboflavin synthase (alpha chain), which is in- volved in the catalysis of the terminal step of riboflavin bio- synthesis (13). The ribC gene of B. henselae is flanked by the genes ribD and ribE, which encode homologues of the ribofla- vin synthesis proteins RibD and RibE. In E. coli, the RibE and RibC proteins form the multienzyme complex riboflavin syn- thase, which catalyzes the terminal step in riboflavin synthesis (3). The gene order of ribD, ribC, and ribE is conserved in B. henselae, B. quintana, B. clarridgeiae, and B. bacilliformis. The clustering suggests that the genes are organized as an operon, which is also the case for riboflavin synthesis genes in the gram-positive bacterium B. subtilis and in gram-negative bac- teria, like Actinobacillus spp. and Photobacterium spp. (15, 35). In the latter species, the rib genes are part of the lux operon (26). Within these operons, the gene order of ribD, ribC, and ribE homologues is different from that in Bartonella species. In other gram-negative organisms, e.g., E. coli, H. pylori, and H. influenzae, the rib genes are randomly distributed in the chro- mosome (3, 5, 14).