Abstract
Background: Arcobacters are important zoonotic pathogens and are transmitted through food and water. They are implicated in causing enteritis in animals and humans. Among the Arcobacter species, a wide genetic diversity has been documented, which reflects continuous evolving nature of these pathogens.
Objectives: To genotype and to know the genetic diversity of Arcobacter spp. (Arcobacter butzleri and Arcobacter cryaerophilus) isolated from different sources in India.
Methods: Enterobacterial repetitive intergenic consensus–polymerase chain reaction (ERIC-PCR) was performed using genomic DNA of 49 Arcobacter isolates (27 A. butzleri and 22 A. cryaerophilus), recovered from a total of 506 samples of chicken meat, poultry skin, dairy cow milk and human stool as template and employing published primers.
Results: ERIC sequence was found to be present in all the 27 A. butzleri isolates which were grouped into 18 subtypes, while it was present in 20 out of 22 A. cryaerophilus isolates which were grouped into 14 subtypes. Less variation was observed within sequences of both the Arcobacter species as revealed in dendrogram analysis. The genotyping of A. butzleri isolates showed the presence of 2–8 distinct bands (∼150 to ∼1600 bp), while A. cryaerophilus showed 1–10 distinct bands (∼120 to ∼2900 bp).
Conclusion:This study is the first report regarding genetic diversity of Indian Arcobacter isolates using ERIC-PCR. Close clustering between arcobacters of human and animal origin are indicative of probable zoonotic significance. So for these purposes, further explorative studies are suggested which would also help revealing the possibility of epidemiological relationships of different Arcobacter spp. as well as their public health concerns.
1. Introduction
Arcobacters are emerging food-borne pathogens having public health concerns and have been reported worldwide in recent years and reported from a variety of foods of animal origin, water and human stool (Snelling et al. 2006; Patyal et al. 2011; Dhama et al. 2013; Ferreira et al. 2013; Mohan et al. 2014). The genus Arcobacter falls under Campylobacteraceae family, the members of which have been associated with human diarrheal disorders and bacteremia. Arcobacters have been associated with enteritis, mastitis and metritis in livestock animals and poultry (Lerner et al. 1994; Houf et al. 2002; Collado & Figueras 2011; Ramees et al. 2014). To date, 18 species of arcobacters have been documented and among these a wide genetic diversity has been reported, which reflects continuous evolving and emerging nature of these pathogens (Collado & Figueras 2011; Figueras et al. 2012; Levican & Figueras 2013; Levican et al. 2013; Sasi Jyothsna et al. 2013; Figueras et al. 2014). For studying genetic diversities and genotyping of bacterial pathogens, several tools are available like Random amplification of polymorphic DNA (RAPD), Restriction fragment length polymorphism (RFLP), Amplified fragment length polymorphism (AFLP), Repetitive extragenic palindromic-PCR, multilocus sequence typing (MLST), pulsed-field gel electrophoresis (PFGE), enterobacterial repetitive intergenic consensus–polymerase chain reaction (ERIC-PCR), sequencing-based methods (Sanger method and pyrosequencing) and phylogenetic analysis (Rivas et al. 2004; Merga et al. 2011; Yıldırım et al. 2011; Bagalakote et al. 2014). Among these, ERIC sequences, also designated as intergenic repetitive units, have been used by many authors (Sharples & Lloyd 1990; Houf et al. 2002) for finding genetic diversity of different pathogenic bacterial species in the Enterobacteriaceae family, since varying sequences are present in different bacterial pathogens. The fingerprints generated with ERIC-PCR were more reproducible and complex than with that of RAPD-PCR (Houf et al. 2002). Recently, ERIC-PCR profiling revealed high genetic diversity amongst Arcobacter spp. recovered from different water sources and sewages (Collado et al. 2010). The molecular diversity in Arcobacter spp. has been reported both within and between the species (Suelam 2012).
ERIC-PCR was selected to study genetic diversity because this method has effectively been applied to Arcobacter isolates involved in gastro-intestinal disease (Vandamme et al. 1993). In comparison with other genotyping methods like sequencing, the ERIC-PCR gives faster results. The presence of multiple parent genotypes for the three most important Arcobacter spp. (A. butzleri, A. cryaerophilus and A. skirrowii) and high genetic recombinations between the progeny of parent genotypes may be the reasons for significant level of heterogeneity in arcobacters; this is indicative of the multiple source contamination events to be happening (Houf et al. 2002; Aydin et al. 2007). Also, depending on the isolation procedure used, different Arcobacter spp. can be isolated. Moreover, a large number of isolates should be characterized in order to identify as many different strains as possible. Compared to RFLP and RAPD technique, the ERIC-PCR has been proved to be the best technique (Houf et al. 2002).
This study was designed for evaluating genetic diversity and genotyping of two important Arcobacter spp., namely A. butzleri and A. cryaerophilus, recovered from chicken meat, poultry skin, dairy cow milk and human stool by using ERIC-PCR.
2. Materials and methods
2.1. Isolation, culture conditions and PCR confirmation of Arcobacter spp.
A total number of 506 samples were collected during the period of August 2012 to May 2013 from human hospitals [human stools (HS) from diarrheic patients, 102], retail meat shops [chicken meat (CM), 151 and poultry skin (PS), 153] and milk suppliers, vendors and dairy farm [dairy cow (DC) milk, 100] from in and around Bareilly region of Uttar Pradesh, India. Culture isolation of arcobacters out of the 506 samples was carried out as per Ramees et al. (2014) at the Division of Veterinary Public Health, Indian Veterinary Research Institute Izatnagar, Bareilly (UP). For this purpose, the samples were inoculated into Arcobacter enrichment broth with CAT (cefoperazone, amphotericin and teicoplanin) supplement (HIMEDIA, India) and incubated micro-aerobically at 30 ºC for 48 hrs. The enriched samples were filtered using 0.45 μm pore size polyethersulfone syringe filter directly on to blood agar plates and incubated under micro-aerobic condition at 30 °C for 48–72 hrs. A total number of 49 Arcobacter pure isolates (27 A. butzleri and 22 A. cryaerophilus) were recovered (Table 1) and maintained in brain heart infusion (BHI) broth enriched with defibrinized sheep blood at −20 °C.
Table 1. Arcobacter butzleri and Arcobacter cryaerophilus isolates used in the study.
All the isolates obtained were subjected to species specific PCR-based amplification assay for confirmation of the presence of DNA of the two Arcobacter species (A. butzleri and A. cryaerophilus) as per the method of Houf et al. (2000). Multiple identified colonies from one cultural isolate obtained from each food or stool sample were selected for DNA extraction and initial screening for species specific identification by PCR and also for further characterization for fingerprinting assay by ERIC-PCR. The genomic DNA for PCR was extracted from the colonies by using DNeasy Blood and Tissue Kit (QIAGEN, USA) following the manufacturer's protocol. Species specific PCR assays were performed for A. butzleri and A. cryaerophilus as reported by Houf et al. (2000). A reference strain of A. butzleri (LMG 10828) obtained from the Belgium Bacterial Collection Centre (BCCM/LMG) and a previously confirmed Indian isolate of A. cryaerophilus VPH/PI1/IVRI/2012 GenBank: KC520495.1 were used for standardization of the PCR assays.
2.2. ERIC-PCR profiling of Arcobacter isolates
ERIC-PCR was employed for evaluating genetic diversity and genotyping of the 49 isolates of the two Arcobacter spp. (A. butzleri and A. cryaerophilus). Before ERIC-PCR protocol, the genomic DNA was run on agarose gel to check DNA integrity with no smearing observed. ERIC-PCR assay using oligonucleotide primer pair was performed as previously described (Versalovic et al. 1991; Houf et al. 2002) with minor modification in order to obtain better band pattern and reproducibility of results. The PCR amplification reaction was carried out with a 25 μl PCR reaction mixture containing 3 μl (50–100 ng) of DNA template, 1.5 units of Taq DNA polymerase (Genetix Biotech Asia, New Dehli, India), 4 μl 10x Taq buffer with 2.5 μl of 2 mM each of the dNTPs, and 25 pmol of each primer of the forward ERIC 1R (5′-ATG AAG CTC CTG GGG ATT CAC- 3′) and reverse ERIC 2 (5′ -AAG TAA GTG ACT GGG GTG AGC G- 3′) primer pair (Eurofins, Banglore, India). The reaction volume was adjusted with nuclease-free water to obtain 25 μl. The amplification cycles included initial denaturation at 94 °C for 5 min, followed by 40 cycles of denaturation at 94 °C for 1 min, annealing at 25 °C for 1 min, and extension at 72 °C for 2 min. The final extension was carried out at 72 °C for 10 min. A thermal cycler (GenePro, Bioer Technology Co., Ltd., Hangzhou, China) was used for ERIC-PCR amplification. The ERIC-PCR products thus generated were characterized by gel electrophoresis on 1.5% agarose gel for 95 min at 80 volts. The interpretation of test results was done by pairwise binary band matching (Tenover et al. 1995). Only the distinct bands observed in ERIC-PCR were considered for analysis by binary scoring pattern, wherein a score of 1 for the presence and 0 for absence of a band was assigned to each Arcobacter isolate. The dendrogram was constructed using the software TREECON for Windows v1.3b (Bioinformatics and Evolutionary Genomics, Belgium) (Van De Peer & De Wachter 1994). Dendrograms were constructed and analyzed separately for the two Arcobacter spp. Numerical index of discrimination was calculated by Simpson's index of diversity (Hunter & Gaston 1988) using the following formula: 
where N = the total number of strains in the sample population; nj = the number of strains belonging to the jth type; and s = the total number of types defined.
3. Results
ERIC sequences were found to be present in all the 27 A. butzleri isolates. There was less variation in ERIC sequences with respect to the isolate of same origin and the typing revealed 2–8 distinct bands in A. butzleri isolates, ranging in sizes from ∼150 to ∼1600 bp (Figure 1). The ERIC-PCR amplified products were distributed in ∼150 bp, ∼160 bp, ∼200 bp, ∼250 bp, ∼310 bp, ∼400 bp, ∼430 bp, ∼500 bp, ∼550 bp, ∼700 bp, ∼750 bp, ∼950 bp, ∼1100 bp, ∼1350 bp and ∼1600 bp molecular weights. Distinct polymorphic bands at ∼450 bp were observed in CM36, CM74, CM133, CM142, DC5, PS66, PS71 and PS90 isolates. Dendogram analysis revealed that some of the A. butzleri isolates recovered from chicken meat and poultry skin from different animals were clustering in the same group, the isolate from dairy cow (DC) milk sample was not found to cluster with other isolates (Figure 3). Dendrogram was constructed from the binary scores of the fingerprint data and it was found that 18 different ERIC patterns were observed within 27 A. butzleri isolates (Table 2).
Table 2. Number fingerprint types generated for A. butzleri isolates with ERIC-PCR.
Published online:
14 November 2014Figure 1. ERIC-PCR profiling for A. butzleri isolates (n = 27). Lane M – molecular weight ladder (100 bp plus), 1-CM3, 2-CM36, 3-CM37, 4-CM54, 5-CM67, 6-CM69, 7- CM74, 8-CM77, 9-CM82, 10-CM 84, 11-CM88, 12-CM109, 13-CM111, 14-CM117, 15-CM133, 16-CM142, 17-CM147, 18-PS13, 19-PS35, 20-DC5, 21-PS66, 22-PS71, 23-PS84, 24-PS85, 25-PS90, 26-PS 141, 27-HS105. CM – chicken meat; PS – poultry skin; HS – human stool; DC – dairy cow milk.
![]({"type":"image","src":"/na101/home/literatum/publisher/tandf/journals/content/tveq20/2014/tveq20.v034.i04/01652176.2014.979511/20141215/images/medium/tveq_a_979511_f0001_b.gif"})
Figure 1. ERIC-PCR profiling for A. butzleri isolates (n = 27). Lane M – molecular weight ladder (100 bp plus), 1-CM3, 2-CM36, 3-CM37, 4-CM54, 5-CM67, 6-CM69, 7- CM74, 8-CM77, 9-CM82, 10-CM 84, 11-CM88, 12-CM109, 13-CM111, 14-CM117, 15-CM133, 16-CM142, 17-CM147, 18-PS13, 19-PS35, 20-DC5, 21-PS66, 22-PS71, 23-PS84, 24-PS85, 25-PS90, 26-PS 141, 27-HS105. CM – chicken meat; PS – poultry skin; HS – human stool; DC – dairy cow milk.
Published online:
14 November 2014Figure 2. ERIC-PCR profiling for A. cryaerophilus isolates (n = 22). M – molecular weight ladder (100 bp plus), 1-PS6, 2-PS15, 3-PS31, 4-PS32, 5-PS33, 6-PS36, 7-PS44, 8-PS46, 9-PS47, 10-PS57, 11-PS112, 12-CM2, 13-CM35, 14-CM39, 15-CM75, 16-CM81, 17-CM93, 18-CM98, 19-CM137, 20-CM139, 21-CM143, 22-HS145. CM – chicken meat, PS – poultry skin, HS – human stool.
![]({"type":"image","src":"/na101/home/literatum/publisher/tandf/journals/content/tveq20/2014/tveq20.v034.i04/01652176.2014.979511/20141215/images/medium/tveq_a_979511_f0002_b.gif"})
Figure 2. ERIC-PCR profiling for A. cryaerophilus isolates (n = 22). M – molecular weight ladder (100 bp plus), 1-PS6, 2-PS15, 3-PS31, 4-PS32, 5-PS33, 6-PS36, 7-PS44, 8-PS46, 9-PS47, 10-PS57, 11-PS112, 12-CM2, 13-CM35, 14-CM39, 15-CM75, 16-CM81, 17-CM93, 18-CM98, 19-CM137, 20-CM139, 21-CM143, 22-HS145. CM – chicken meat, PS – poultry skin, HS – human stool.
Published online:
14 November 2014Figure 3. Dendrogram analysis and a schematic diagram showing distinct band patterns of A. butzleri isolates obtained from ERIC-PCR assay.
![]({"type":"image","src":"/na101/home/literatum/publisher/tandf/journals/content/tveq20/2014/tveq20.v034.i04/01652176.2014.979511/20141215/images/medium/tveq_a_979511_f0003_b.gif"})
Figure 3. Dendrogram analysis and a schematic diagram showing distinct band patterns of A. butzleri isolates obtained from ERIC-PCR assay.
The ERIC sequence was present in 20 out of the 22 A. cryaerophilus isolates, with bands ranging in size from ∼120 to ∼2900 bp and smearing was noticed with the remaining two isolates in gel picture (Figure 2). Distinct polymorphic bands at ∼520 bp were observed in PS33, CM35, CM39, CM75, CM81, CM93 and CM98 isolates of A. cryaerophilus. Dendogram analysis revealed that some of the A. cryaerophilus isolates of chicken meat and poultry skin origin showed clustering in the same group (CM75, CM39 and PS31). Dendrogram was constructed from the binary scores of the fingerprint data and it was found that 14 ERIC-PCR subtypes were observed within all the isolates of A. cryaerophilus (Table 3). Discriminatory power of ERIC-PCR technique for A. butzleri and A. cryaerophilus isolates was found to be 0.9715 and 0.961, respectively. Dendogram analysis of A. butzleri showed poultry skin (PS) sample number 35 and human stool (HS) sample number 105 to be clustered together in the same group (Figure 3), while that of A. cryaerophilus showed poultry skin sample number 112 and human stool sample number 145 to be clustered together in the same group (Figure 4).
Table 3. Number of fingerprint types generated for A. cryaeophilus isolates with ERIC-PCR.
Published online:
14 November 2014Figure 4. Dendrogram analysis and a schematic diagram showing distinct band patterns of A. cryaerophilus isolates obtained from ERIC-PCR assay.
![]({"type":"image","src":"/na101/home/literatum/publisher/tandf/journals/content/tveq20/2014/tveq20.v034.i04/01652176.2014.979511/20141215/images/medium/tveq_a_979511_f0004_b.gif"})
Figure 4. Dendrogram analysis and a schematic diagram showing distinct band patterns of A. cryaerophilus isolates obtained from ERIC-PCR assay.
4. Discussion
ERIC-PCR revealed genomic diversity between the two Arcobacter spp. (A. butzleri and A. cryaerophilus) with ERIC sequences found in all the 27 isolates of A. butzleri with less variation (2–8 distinct bands) and in 20 A. cryaerophilus isolates (1–10 distinct bands). In dendogram analysis, the clustering pattern of some of the A. butzleri and A. cryaerophilus isolates of chicken meat (CM) and poultry skin (PS) origin in the same group indicated possible homogeneity and their phylogenic relationship. The A. butzleri isolate from dairy cow (DC) milk sample did not cluster with other isolates, indicating the possibility of heterogeneity as per the source of isolates. Fingerprint data by ERIC-PCR showed 18 genotypes of A. butzleri and 14 genotypes of A. cryaerophilus, which showed genomic diversity within the Arcobacter spp.
Earlier studies have also reported arcobacters to have high genetic diversity within and also between the species (Collado et al. 2010; Kayman et al. 2012). Using MLST, a high genetic diversity among Arcobacter spp. and their continuous evolving nature has been reported from United Kingdom (Merga et al. 2011). Subtyping of arcobacters, isolated from cattle faeces in Belgium, by using ERIC-PCR revealed a great degree of heterogeneity with the presence of 22 different subtypes (Van Driessche et al. 2005). In this study, ERIC-PCR revealed 18 subtypes of A. butzleri and 14 subtypes A. cryaerophilus, recovered from different sources. Houf et al. (2002) reported 91 genotypes of A. butzleri out of 182 isolates and 40 genotypes out of 42 isolates of A. cryaerophilus obtained from poultry products. Suelam (2012) reported nine genotypes out of 10 Arcobacter isolates from rabbit. Collado et al. (2010) reported 248 genotypes of A. butzleri out of 275 isolates and 60 genotypes out of 63 isolates of A. cryaerophilus obtained from treated drinking water. Other authors have also reported discrimination and diversity in Arcobacter spp. obtained from different sources from various countries (Vandamme et al. 1993; Van Driessche et al. 2004; Aydin et al. 2007). However, a study using PFGE reported homogeneity among the A. butzleri isolates from different meat species (chicken, lamb, beef and pork) obtained from the same setting up on the same day which is indicative of a common source of contamination (Rivas et al. 2004).
ERIC-PCR discriminatory powers of 0.9715 and 0.961 for A. butzleri and A. cryaerophilus isolates, respectively, indicated ERIC-PCR to be a highly desirable genotyping method since discriminatory powers above 0.90 are considered highly significant (Hunter & Gaston 1988). In dendogram analysis, clustering together of one sample each of both A. butzleri and A. cryaerophilus isolates of poultry skin and human stool in the same group indicated similarity in phylogeny and possibility of zoonotic nature of arcobacters.
The continuous emergence and evolution of arcobacters, new species and diversities being reported, and upcoming reports of detection and isolation from worldwide countries from different sources (animals, humans, variety of food sources) along with zoonotic concerns have placed this important food-borne pathogen at global scenario (Manke et al. 1998; Van Driessche et al. 2005; Aydin et al. 2007; Collado et al. 2010; De Smet et al. 2010; Patyal et al. 2011; Kayman et al. 2012; Mohan et al. 2014; Ramees et al. 2014). Thus, this study reporting for the first time genotyping and diversity of A. butzleri and A. cryaerophilus (recovered from chicken meat, dairy cow milk, poultry skin, and human stools) in India adds to the heterogeneity reports among Arcobacter spp. worldwide, supporting diversity among same species. The dendogram analysis also indicated the genetic similarity among Arcobacter isolates recovered from human and chicken meat/poultry skin, which reveals the possibility of epidemiological relationship and evolutionary pattern between Arcobacter isolates of human and animal origin and its feasible zoonotic significance. In this context, further extensive epidemiological surveillance along with molecular characterization, genotyping and finding diversities among arcobacters recovered from humans, animals and various food sources are indicated. This would altogether help in determining the possibility of evolutionary and epidemiological relationships of different Arcobacter spp. as well as their public health concerns. These attempts would overall help in designing and adapting appropriate prevention and control strategies to counter this important and emerging food-borne pathogen.
| Serial no. | Type of samples | No. of samples | Arcobacter spp. isolated | A. butzleri | A. cryaerophilus |
|---|---|---|---|---|---|
| (1) | Human stool (HS) | 102 | 2 | 1 | 1 |
| (2) | Food samples | ||||
| (1) Chicken meat (CM) | 151 | 27 | 17 | 10 | |
| (2) Dairy cow (DC) milk | 100 | 1 | 1 | – | |
| (3) | Poultry skin (PS) | 153 | 19 | 8 | 11 |
| Total | 506 | 49 | 27 | 22 |
| Origin | ||||
|---|---|---|---|---|
| Types | CM | PS | DC | HS |
| Type A | √(3) | – | – | – |
| Type B | – | √(2) | – | – |
| Type C | √(1) | √(1) | – | – |
| Type D | √(1) | – | – | – |
| Type E | √(1) | – | – | – |
| Type F | √(2) | – | – | – |
| Type G | – | √(1) | – | √(1) |
| Type H | √(1) | – | – | – |
| Type I | √(1) | – | – | – |
| Type J | √(2) | – | – | – |
| Type K | √(1) | – | – | – |
| Type L | √(2) | – | – | – |
| Type M | – | – | √(1) | – |
| Type N | √(1) | – | – | – |
| Type O | – | √(1) | – | – |
| Type P | – | √(1) | – | – |
| Type Q | √(1) | – | – | – |
| Type R | – | √(2) | – | – |
| Origin | ||||
|---|---|---|---|---|
| Types | CM | PS | DC | HS |
| Type A | – | √(1) | – | √(1) |
| Type B | √(1) | √(1) | – | – |
| Type C | – | √(1) | – | – |
| Type D | √(2) | – | – | – |
| Type E | √(1) | – | – | – |
| Type F | √(3) | – | – | – |
| Type G | – | √(1) | – | – |
| Type H | – | √(2) | – | – |
| Type I | √(1) | – | – | – |
| Type J | √(1) | – | – | – |
| Type K | – | √(2) | – | – |
| Type L | – | √(1) | – | – |
| Type M | – | √(2) | – | – |
| Type N | √(1) | – | – | – |
Acknowledgements
The authors are thankful to Indian Veterinary Research Institute for supporting this research.
References
- Aydin F, Gumussoy KS, Atabay HI, Ica T, Abay, S. 2007. Prevalence and distribution of Arcobacter species in various sources in Turkey and molecular analysis of isolated strains by ERIC-PCR. J Appl Microbiol. 103(1):27–35. [Crossref], [PubMed], [Web of Science ®], [Google Scholar]
- Bagalakote PS, Rathore RS, Ramees TP, Mohan HV, Sumankumar M, Agarwal RK, Kumar A, Dhama K. 2014. Molecular characterization of Arcobacter isolates using randomly amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR). Asian J Anim Vet Adv. 9(9):543–555. [Crossref], [Google Scholar]
- Collado L, Figueras MJ. 2011. Taxonomy, epidemiology and clinical relevance of the genus Arcobacter. Clin Microbiol Rev. 24:174–192. [Crossref], [PubMed], [Web of Science ®], [Google Scholar]
- Collado L, Kasimir G, Perez U, Bosch A, Pinto R, Saucedo G, Huguet JM, Figueras MJ. 2010. Occurrence and diversity of Arcobacter spp. along the Llobregat river catchment, at sewage effluents and in a drinking water treatment plant. Water Res. 44:3696–3702. [Crossref], [PubMed], [Web of Science ®], [Google Scholar]
- De Smet S, De Zutter L, Van Hende J, Houf K. 2010. Arcobacter contamination on pre- and post-chilled bovine carcasses and in minced beef at retail. J Appl Microbiol. 108(1):299–305. [Crossref], [PubMed], [Web of Science ®], [Google Scholar]
- Dhama K, Rajagunalan S, Chakraborty S, Verma AK, Kumar A, Tiwari R, Kapoor S. 2013. Food-borne pathogens of animal origin-diagnosis, prevention, control and their zoonotic significance: a review. Pakistan J Biol Sci. 16(20):1076–1085. [Crossref], [PubMed], [Google Scholar]
- Ferreira S, Fraqueza MJ, Queiroz JA, Domingues FC, Oleastro M. 2013. Genetic diversity, antibiotic resistance and biofilm-forming ability of Arcobacter butzleri isolated from poultry and environment from a Portuguese slaughterhouse. Int J Food Microbiol. 162:82–88. [Crossref], [PubMed], [Web of Science ®], [Google Scholar]
- Figueras MJ, Levican A, Collado L. 2012. Updated 16S rRNA-RFLP method for the identification of all currently characterized Arcobacter spp. BMC Microbiol. 12:292. doi:10.1186/1471-2180-12-292 [Crossref], [PubMed], [Web of Science ®], [Google Scholar]
- Figueras MJ, Levican A, Pujol I, Ballester F, Rabada Quilez MJ, Gomez-Bertomeu F. 2014. A severe case of persistent diarrhoea associated with Arcobacter cryaerophilus but attributed to Campylobacter sp. and a review of the clinical incidence of Arcobacter spp. New Microbes and New Infect. 2(2):31–37. [Crossref], [Google Scholar]
- Houf K, De Zutter L, Van Hoof J, Vandamme P. 2002. Assessment of the genetic diversity among arcobacters isolated from poultry products by using two PCR-based typing methods. Appl Environ Microbiol. 68(5):2172–2178. [Crossref], [PubMed], [Web of Science ®], [Google Scholar]
- Houf K, Tutenel A, De Zutter L, Van Hoof J, Vandamme P. 2000. Development of a multiplex PCR assay for the simultaneous detection and identification of Arcobacter butzleri, Arcobacter cryaerophilus and Arcobacter skirrowii. FEMS Immunol Med Microbiol. 49(3):337–345. [Google Scholar]
- Hunter PR, Gaston MA. 1988. Numerical index of the discriminatory ability of typing systems: an application of Simpson's index of diversity. J Clin Microbiol. 26:2465–2466. [Crossref], [PubMed], [Web of Science ®], [Google Scholar]
- Kayman T, Abay S, Hizlisoy H, Atabay HI, Diker KS, Aydin F. 2012. Emerging pathogen Arcobacter spp. in acute gastroenteritis: molecular identification, antibiotic susceptibilities and genotyping of the isolated arcobacters. J Med Microbiol. 61(10):1439–1444. [Crossref], [PubMed], [Web of Science ®], [Google Scholar]
- Lerner J, Brumberger V, Preac-Mursic V. 1994. Severe diarrhea associated with Arcobacter butzleri. Eur J Clin Microbiol Infect Dis. 13:660–662. [Crossref], [PubMed], [Web of Science ®], [Google Scholar]
- Levican A, Collado L, Figueras MJ. 2013. Arcobacter cloacae sp. nov. and Arcobacter suis sp. nov., two new species isolated from food and sewage. Syst Appl Microbiol. 36:22–27. [Crossref], [PubMed], [Web of Science ®], [Google Scholar]
- Levican A, Figueras MJ. 2013. Performance of five molecular methods for monitoring Arcobacter spp. BMC Microbiol. 13:220. doi: 10.1186/1471-2180-13-220 [Crossref], [PubMed], [Web of Science ®], [Google Scholar]
- Manke TR, Wesley IV, Dickson JS, Harmon KM. 1998. Prevalence and genetic variability of Arcobacter species in mechanically separated turkey. J Food Prot. 61(12):1623–1628. [PubMed], [Web of Science ®], [Google Scholar]
- Mohan HV, Rathore RS, Dhama K, Ramees TP, Patyal A, Bagalkot PS, Wani MY, Bhilegaonkar KN, Kumar A. 2014. Prevalence of Arcobacter spp. in humans, animals and foods of animal origin in India based on cultural isolation, antibiogram, PCR and multiplex PCR detection. Asian J Anim Vet Adv. 9(8):452–466. [Crossref], [Google Scholar]
- Merga JY, Leatherbarrow AJH, Winstanley C, Bennett M, Hart CA, Miller WG, Williams NJ. 2011. Comparison of Arcobacter isolation methods, and diversity of Arcobacter spp. in Cheshire, United Kingdom. Appl Environ Microbiol. 77(5):1646–1650. [Crossref], [PubMed], [Web of Science ®], [Google Scholar]
- Patyal A, Rathore RS, Mohan HV, Dhama K, Kumar A. 2011. Prevalence of Arcobacter spp. in humans, animals and foods of animal origin including sea food from India. Transboundary and Emerg Dis. 58:402–410. [Crossref], [PubMed], [Web of Science ®], [Google Scholar]
- Ramees TP, Rathore RS, Bagalkot PS, Mohan HV, Kumar A, Dhama K. 2014. Detection of Arcobacter butzleri and Arcobacter cryaerophilus in clinical samples of humans and foods of animal origin by cultural and multiplex PCR based methods. Asian J Anim Vet Adv. 9(4):243–252. [Crossref], [Google Scholar]
- Rivas L, Fegan N, Vanderlinde P. 2004. Isolation and characterisation of Arcobacter butzleri from meat. Int J Food Microbiol. 91(1):31–41. [Crossref], [PubMed], [Web of Science ®], [Google Scholar]
- Sasi Jyothsna TS, Rahul K, Ramaprasad EV, Sasikala Ch, Ramana ChV. 2013. Arcobacter anaerophilus sp. nov., isolated from an estuarine sediment and emended description of the genus Arcobacter. Int J Syst Evol Microbiol. 46:19–25. [Google Scholar]
- Sharples GJ, Lloyd RG. 1990. A novel repeated sequence located in the intergenic regions of bacterial chromosomes. Nucleic Acids Res. 18:6503–6508. [Crossref], [PubMed], [Web of Science ®], [Google Scholar]
- Snelling WJ, Matsuda M, Moore JE, Dooley JSG. 2006. Under the microscope: Arcobacter. Lett Appl Microbiol. 42:7–14. [Crossref], [PubMed], [Web of Science ®], [Google Scholar]
- Suelam IIA. 2012. Isolation and identification of Arcobacter species recovered from rabbits in Zagazig, Egypt. Int J Microbiol Res. 3(2):87–92. [Google Scholar]
- Tenover FC, Arbeit RD, Goering RV, Mickelsen PA, Murray BE, Persing DH, Swaminathan B. 1995. Interpreting chromosomal DNA restriction patterns produced by pulsed-field gel electrophoresis: criteria for bacterial strain typing. J Clin Microbiol. 33:2233–2239. [Crossref], [PubMed], [Web of Science ®], [Google Scholar]
- Vandamme P, Giesendorf BA, Van belkum A, Pierard D, Lauwers S, Kersters K, Butzler P, Goossens H, Quint WG. 1993. Discrimination of epidemic and sporadic isolates of Arcobacter butzleri by polymerase chain reaction-mediated DNA fingerprinting. J Clin Microbiol. 31(12):3317–3319. [PubMed], [Web of Science ®], [Google Scholar]
- Van De Peer Y, De Wachter Y. 1994. TREECON for Windows: a software package for the construction and drawing of evolutionary trees for the Microsoft Windows environment. Comput Appl Biosci. 10:569–70. [Crossref], [PubMed], [Google Scholar]
- Van Driessche E, Houf K, Vangroenweghe F, De Zutter L, Van Hoof J. 2005. Prevalence, enumeration and strain variation of Arcobacter species in the faeces of healthy cattle in Belgium. Vet Microbiol. 105(2):149–154. [Crossref], [PubMed], [Web of Science ®], [Google Scholar]
- Van Driessche E, Houf K, Vangroenweghe F, Nollet N, De Zutter L, Vandamme P, Van Hoof J. 2004. Occurence and strain diversity of Arcobacter species isolated from healthy Belgian pigs. Res Microbiol. 155:662–666. [Crossref], [PubMed], [Web of Science ®], [Google Scholar]
- Versalovic J, Koeuth T, Lupski JR. 1991. Distribution of repetitive DNA sequences in eubacteria and application to fingerprinting of bacterial genomes. Nucleic Acids Res. 19:6823–6831. [Crossref], [PubMed], [Web of Science ®], [Google Scholar]
- Yıldırım IH, Yıldırım SC, Koçak C. 2011. Molecular methods for bacterial genotyping and analyzed gene regions. J Microbiol Infect Dis. 1(1):42–46. [Crossref], [Google Scholar]