Tick-borne rickettsial diseases (TBRD) are commonly encountered in medical and veterinary clinical settings. The control of these diseases is difficult, requiring disruption of a complex transmission chain involving a vertebrate host and ticks. The geographical distribution of the diseases is related to distribution of the vector, which is an indicator of risk for the population. A total of 1,107 ticks were collected by tick dragging from forests, ecotourism parks and hosts at 101 sites in 22 of the 32 states of Mexico. Collected ticks were placed in 1.5 mL cryovials containing 70% ethanol and were identified to species. Ticks were pooled according to location/host of collection, date of collection, sex, and stage of development. A total of 51 ticks were assayed by polymerase chain reaction (PCR) to confirm species identification using morphological methods. A total of 477 pools of ticks were assayed using PCR techniques for selected tick-borne pathogens. Anaplasma phagocytophilum was the most commonly detected pathogen (45 pools), followed by, Ehrlichia (E.) canis (42), Rickettsia (R.) rickettsii (11), E. chaffeensis (8), and R. amblyommii (1). Rhipicephalus sanguineus was the tick most frequently positive for selected pathogens. Overall, our results indicate that potential tick vectors positive for rickettsial pathogens are distributed throughout the area surveyed in Mexico.
Anaplasma phagocytophilum ; Animals* ; Ehrlichia ; Ehrlichia canis ; Ehrlichia chaffeensis ; Ethanol ; Forests ; Humans* ; Mexico* ; Polymerase Chain Reaction ; Rhipicephalus sanguineus ; Rickettsia ; Ticks* ; Vertebrates

Ehrlichia sennetsu is the causative agent of human Sennetsu ehrlichiosis. Ehrlichiosis is an acute and occasionally chronic infectious disease caused by obligate intracellular bacteria in the family Rickettsiaceae. To understand the seroepidemiological patterns of ehrlichiosis in Korea, a total of 2,625 patients with acute febrile episode reported from 1990 to 1992 were surveyed using an indirect fluorescent antibody assay (IFA). The result was as follows. Seropositivity for ehrlichiosis was 3.23% by excluding highly cross-reacted sera with other rickettsial antigens. Sera reacted to E. sennetsu showed the cross reaction with other rickettsia as in the order of R. typhi 49.6%, R. conorii 31.6%, R. japonica 28.1%, C. burnetii 26.4%, R. sibirica 25.8%, O. tsutsugamushi 25.8%, R. akari 25.4%, and R. prowazekii 25.4%. Sexual difference in the seropositivity was not noted. The age groups of fifties and under the tenth showed higher prevalence than others. Seropositivity was most prevalent in July and August. As for regional distribution, Chonbuk (10.5%) showed the highest seropositive rate. Geographical distribution of the seropositivity covered most area except Cheju province in Korea.
Bacteria ; Communicable Diseases ; Cross Reactions ; Ehrlichiosis* ; Humans ; Jeju-do ; Jeollabuk-do ; Korea ; Neorickettsia sennetsu ; Prevalence ; Rickettsia ; Rickettsiaceae

Coxiella burnetii is the etiological agent of Q fever, that may occur either acutely or the chronically. To understand the seroepidemiological patterns of C. burnetii infection in Korea, we examined a total of 3,178 sera from patients with acute febrile episodes by using indirect immunofluorescence assay (IFA) for detectable antibodies to C. burnetii and other eight rickettsial antigens. The IFA seropositivity>or=1:20 for C. burnetii phase II was 11.5% (368 out of 3,178 sera). The co-existence of antibodies to other rickettsial antigens was found in 216 out of the 368 positive sera. Thirty-seven point five percent (n=138) had antibodies to R. tsutsugamushi (cutoff>or=1:20), 16% (n=59) to Ehrlichia sennetsu, 14.9% (n=55) to Rickettsia typhi, 13.5% (n=50) to R. akari, 11.4% (n=42) to R. japonica, 8.9% (n=33) to R. prowazekii, 7.6% (n=28) to R. sibirica, and 6.7% (n=25) to R. conorii by IFA, respectively. These results are consistent with previous reports documenting diverse serum cross-reactivity in chronic Q fever. Therefore we excluded the samples that reacted to other rickettsial antigens at same or higher titers than to C. burnetii, resulting in the seropositive rate of 4.1%. The serological prevalence was 2% (n=64) when the conventional cut-off titer of 1:80 was used. Our results suggest that infections with C. burnetii are more prevalent than expected previously and should be differentially diagnosised for febrile illness occurring after exposure to ticks or other vectors.
Antibodies ; Coxiella burnetii* ; Coxiella* ; Diagnosis ; Fluorescent Antibody Technique, Indirect ; Humans ; Korea ; Neorickettsia sennetsu ; Prevalence ; Q Fever ; Rickettsia ; Rickettsia typhi ; Seroepidemiologic Studies* ; Ticks

To detect Rickettsia, we have developed a nested PCR method amplifying the groEL gene. Rickettsia strains were successfully amplified by this PCR method but the microorganisms causing other febrile diseases, such as Orientia tsutsugamushi, Coxiella burnetii, Ehrlichia sennetsu, Borrelia burgdorferi sensu lato, Borrelia hermsii, and Leptospira interrogans were not amplified. This PCR assay was applied to detect Rickettsia DNA from 100 ticks. Sixteen Haemaphysalis longicornis ticks were positive by this PCR assay. These results suggest that the new nested PCR method might be sensitive and useful for discrimination between Rickettsia and other febrile disease-causing microorganisms.
Borrelia ; Borrelia burgdorferi Group ; Coxiella burnetii ; Discrimination (Psychology) ; DNA ; Leptospira interrogans ; Neorickettsia sennetsu ; Orientia tsutsugamushi ; Polymerase Chain Reaction* ; Rickettsia* ; Ticks

In a one-step fermentation system of vitamin C production with Gluconobacter oxydans and Ketogulonicigenium vulgare, a functional module of α-lipoic acid biosynthesis was constructed in G. oxydans. The engineered G. oxydans was co-cultured with K. vulgare to enhance the growth and 2-keto-L-gulonic acid (2-KGA) production of K. vulgare. This one-step fermentation system alleviated the growth inhibition during the mono-culture of K. vulgare and strengthened the interaction between the two bacteria. Moreover, the yield of vitamin C precursor (2-KGA) increased to 73.34 g/L (the control group was 59.09 g/L), and the conversion of D-sorbitol to 2-KGA increased to 86.0%. This study provides a new idea for further optimizing the one-step fermentation system of vitamin C production.
Ascorbic Acid ; Fermentation ; Gluconobacter oxydans ; Rhodobacteraceae ; Thioctic Acid ; biosynthesis

A total of 1,395 Haemaphysalis longicornis ticks collected from Jeju Island of Korea were examined by 16S rRNA gene-based nested PCR for the presence of infection with Anaplasma and Ehrlichia species. Template DNAs to detect the tick-borne pathogens were prepared from a total 506 tick pools. Eight genera of Anaplasma and six Ehrlichia by 16S rRNA gene PCR and sequencing analysis were identified. A. phagocytophilum was the most prevalent (27 [1.9%]) by nested PCR, followed by A. bovis (5 [0.4%]), E. chaffeensis (4 [0.2%]), and A. centrale (1 [0.1%]). In the phylogenetic analysis based on 16S rRNA sequences, eight genera of Anaplasma group (> 99.4% homology) and six Ehrlichia group (> 99.5% homology) were close to deposited A. marginale strains (AF309867, AF414874, and FJ226454) and Ehrlichia sp. (DQ324547), respectively. Three Anaplasma species groups A. phagocytophilum (group A), A. bovis (group B), and A. centrale (group C) and one Ehrlichia species E. chaffeensis (group D) were determined by comparing with Anaplasma and Ehrlichia related sequences. First, twenty-eight A. phagocytophilum clones belonging to group A were divided into 7 genotypes. The sequence similarity among genotypes A1 to A4 was very high (> 99.6%). Genotype B2 was close to A. bovis from Korea (99.7%). Genotype D1 was close to known E. chaffeensis strains (M73222, AF147752, and AY350424) and their similarity value was 99.7%. In conclusion, the genera of Anaplasma/Ehrlichia, A. phagocytophilum, and E. chaffeensis identified in predominant H. longicornis ticks were ubiquitous throughout the Jeju Island. The various native groups have been found through sequence identities and phylogenetic analysis.
Anaplasma ; Anaplasma phagocytophilum ; Clone Cells ; DNA ; Ehrlichia ; Ehrlichia chaffeensis ; Genes, rRNA ; Genotype ; Korea ; Polymerase Chain Reaction ; Ticks

The study of canine vector-borne diseases in the Philippines started in the 1970s but only gained interest in the past decade. Characterization of such diseases in the Philippines remains incomplete, thus, it is necessary to obtain additional information on the prevalence and diversity of canine tick-borne diseases in the country. In this study, blood samples were obtained at two veterinary clinics in Metro Manila, Philippines from 114 dogs suspected of having canine tick-borne pathogens. Polymerase chain reaction (PCR) was performed on whole blood DNA extracts followed by sequencing, and the following pathogens were detected: Hepatozoon (H.) canis (5.26%), Babesia (B.) vogeli (5.26%), Ehrlichia (E.) canis (4.39%), and Anaplasma platys (3.51%). Additionally, a set of multiplex PCR primers were developed to detect H. canis, Babesia spp. (B. canis and B. vogeli), and E. canis in canine blood. Multiplex and conventional single-reaction PCR results for the 114 dog blood samples were similar, except for one H. canis sample. Multiplex PCR is, therefore, a useful tool in screening infected dogs in veterinary clinics. This study's results, together with those of previous studies in the country, show that canine vector-borne pathogens are an emerging veterinary concern in the Philippines.
Anaplasma* ; Animals ; Babesia* ; DNA ; Dogs* ; Ehrlichia canis* ; Ehrlichia* ; Hospitals, Animal ; Mass Screening ; Multiplex Polymerase Chain Reaction ; Philippines* ; Polymerase Chain Reaction ; Prevalence ; Tick-Borne Diseases

Bioremediation is one of the most effective ways to treat and dispose of chlorinated hydrocarbons, and methanotrophs are potentially useful to do so. Recent studies found that facultative methanotrophs can use compounds containing C-C bond as sources of carbon and energy, thus overcoming the limitation that obligate methanotrophsone uses only C1 compounds for this process. This is a unique metabolic approach that is becoming increasingly attractive in the field of contaminant biodegradation. Here, we summarized the bioremediation of chlorinated hydrocarbons by obligate and facultative methanotrophs. This process involves the degradation of various chlorinated hydrocarbons by diverse strains, including pure cultures and mixed cultures. We also compare the activity expression and catalytic properties of different types of methane monooxygenases in various substrates. We furthermore summarize the kinetic characteristics of the degradation of chlorinated hydrocarbons using the model strain Methylosinus trichosporium OB3b, and outline the degradation and potential of chlorinated hydrocarbons by facultative methanotrophs. Lastly, we discuss current problems and future research directions for degradation of chlorinated hydrocarbons by methanotrophs.
Biodegradation, Environmental ; Hydrocarbons, Chlorinated ; metabolism ; Methylosinus trichosporium ; metabolism ; Oxygenases ; metabolism

No abstract available.
Rickettsia typhi* ; Rickettsia*

Rodents are well-known reservoirs and vectors of many emerging and re-emerging infectious diseases, but little is known about their role in zoonotic disease transmission in Bhutan. In this study, a cross-sectional investigation of zoonotic disease pathogens in rodents was performed in Chukha district, Bhutan, where a high incidence of scrub typhus and cases of acute undifferentiated febrile illness had been reported in people during the preceding 4–6 months. Twelve rodents were trapped alive using wire-mesh traps. Following euthanasia, liver and kidney tissues were removed and tested using PCR for Orientia tsutsugamushi and other bacterial and rickettsial pathogens causing bartonellosis, borreliosis, human monocytic ehrlichiosis, human granulocytic anaplasmosis, leptospirosis, and rickettsiosis. A phylogenetic analysis was performed on all rodent species captured and pathogens detected. Four out of the 12 rodents (33.3%) tested positive by PCR for zoonotic pathogens. Anaplasma phagocytophilum, Bartonella grahamii, and B. queenslandensis were identified for the first time in Bhutan. Leptospira interrogans was also detected for the first time from rodents in Bhutan. The findings demonstrate the presence of these zoonotic pathogens in rodents in Bhutan, which may pose a risk of disease transmission to humans.
Anaplasma ; Anaplasma phagocytophilum ; Anaplasmosis ; Animals ; Bartonella ; Bartonella Infections ; Bhutan ; Communicable Diseases, Emerging ; Ehrlichiosis ; Euthanasia ; Humans ; Incidence ; Kidney ; Leptospira ; Leptospira interrogans ; Leptospirosis ; Liver ; Orientia tsutsugamushi ; Polymerase Chain Reaction ; Rodentia ; Scrub Typhus ; Zoonoses