Occurrence, virulence gene and antimicrobial susceptibility profiles of Arcobacter sp. isolated from catla (Catla catla) in India

Arcobacter species isolated from human stool samples, animal products, ready-to-eat salad mixes, and ambient water: prevalence, antimicrobial susceptibility, and virulence gene profiles

INTRODUCTION

Arcobacter species are emerging foodborne pathogens increasingly associated with human illness worldwide. They are commonly found in the gastrointestinal tracts of animals and are frequently isolated from various food sources, including raw meat, poultry, and seafood. The aim of this study is to investigate the antimicrobial resistance patterns of Arcobacter spp. isolated from human stool samples, animal products, ready-to-eat salad mixes, and ambient water, assess the presence of resistance genes, and explore their potential implications for public health.

METHODS

In this study, a total of 683 samples were collected from the Shahrekord area over a 12-month period. Samples were obtained from human stool, chicken meat, raw cow milk, RTE salad mixes, and environmental water sources. Two different methods were used to detect Arcobacter, depending on the sample type: bacteriological isolation and identification, and molecular identification. After identification, antimicrobial susceptibility testing was conducted. Polymerase chain reaction (PCR) was used to identify ten putative Arcobacter virulence and resistance genes.

FINDINGS

The results revealed that Arcobacter spp. were present in 26.06% (178 out of 683) of the tested samples, with varying isolation rates across different sample types. A. butzleri being the most commonly isolated species across all sample types, while A. cryaerophilus was restricted to RTE salads, surface waters, and chicken meat. Notably, A. skirrowii was only isolated from chicken meat and environmental water. The differences of Arcobacter spp. in prevalence between the sample types were statistically significant (p < 0.05), and no significant seasonal variation was found across the sampling periods (p > 0.05). PCR analysis for ten putative virulence genes indicated that the cadF gene was present in all Arcobacter isolates. Similarly, 83.33% of the tested strains harbored the ciaB gene, while other genes were less frequently detected. Regarding resistance genes, tet(O) (7.69%) was the most identified gene, followed by blaOXA-61 (4.37%).

CONCLUSION

In conclusion, this study highlights the alarming prevalence of antimicrobial resistance in Arcobacter spp. Monitoring Arcobacter spp. resistance can be achieved through surveillance, risk assessments, antibiotic stewardship in agriculture, public education, research collaborations, rapid diagnostics, and harmonized policies, all aimed at reducing contamination and safeguarding public health effectively.

Arcobacteraceae: An Exploration of Antibiotic Resistance Featuring the Latest Research Updates

The Arcobacteraceae bacterial family includes species isolated from animals and related food products. Moreover, these species have been found in other ecological niches, including water. Some species, particularly Arcobacter butzleri and Arcobacter cryaerophilus, have been isolated from human clinical cases and linked to gastrointestinal symptoms. The presence of antibiotic-resistant strains is a concern for public health, considering the possible zoonoses and foodborne infections caused by contaminated food containing bacteria resistant to antibiotic treatments. This review aims to highlight the importance of antibiotic resistance in Arcobacter spp. isolates from several sources, including information about antibiotic classes to which this bacterium has shown resistance. Arcobacter spp. demonstrated a wide spectrum of antibiotic resistance, including several antibiotic resistance genes. Antibiotic resistance genomic traits include efflux pumps and mutations in antibiotic target proteins. The literature shows a high proportion of Arcobacter spp. that are multidrug-resistant. However, studies in the literature have primarily focused on the evaluation of antibiotic resistance in A. butzleri and A. cryaerophilus, as these species are frequently isolated from various sources. These aspects underline the necessity of studies focused on several Arcobacter species that could potentially be isolated from several sources.

Profile of Aliarcobacter spp. from edible giblets: Genetic diversity, antibiotic resistance, biofilm formation

Aliarcobacter spp. are recognized as emerging foodborne pathogens and consumption of foods contaminated with them can be a hazard to human and animal health. This study was conducted to investigate the prevalence of Aliarcobacter spp. in edible internal organs of different animal species from retail markets and giblet sellers. Additionally, this study was focused on the antimicrobial resistance, virulence profiles, biofilm-forming capabilities, and phylogenetic relationships of obtained isolates. A total of 270 samples were analyzed from which, 28 (10.4 %) were isolated as Aliarcobacter spp. by conventional methods. Within the 28 Aliarcobacter spp. isolates, 17 (60.7 %) were identified as A. butzleri, 10 (35.7 %) were A. cryaerophilus and one (3.5 %) was A. skirrowii by PCR method. The disc diffusion method showed that the highest resistance rate of Aliarcobacter spp. was seen against oxacillin (78.5 %), and 20 (71.4 %) out of the 28 isolates exhibited multidrug resistance (MDR). Out of the 28 isolates, mviN, pldA, tlyA, and hecB virulence genes were detected in 85.7 %, 46.4 %, 46.4 %, and 3.5 %, respectively, but irgA, Cj1349, ciaB, cadF, and hecA genes were not detected. According to the microplate test, 27 (96.4 %) isolates had weak biofilm ability while one A. cryaerophilus isolate (3.6 %) exhibited strong biofilm formation. ERIC-PCR band patterns suggested that isolated Aliarcobacter spp. from giblets, have different contamination sources. The presence of pathogenic and multidrug-resistant Aliarcobacter spp. in food poses a potential risk to public health and control measures throughout the food chain are necessary to prevent the spread of these strains.

Seasonal variation significantly affected bacterioplankton and eukaryoplankton community composition in Xijiang River, China

Both bacterioplankton and eukaryoplankton communities play important roles in the geochemical cycles and energy flows of river ecosystems. However, whether a seasonal change in bacterioplankton and eukaryoplankton communities is synchronous remains unclear. To test the synchronicity and analyze how physical and chemical environmental factors affect these communities, we compared bacterioplankton and eukaryoplankton communities in surface water samples between March (dry season) and June (rainfall season) considering water environmental factors. Our results showed that there was no significant difference in operational taxonomic unit number, Shannon index, and Chao1 index in bacterioplankton and eukaryoplankton communities between March and June. However, principal component analysis showed that the communities were significantly different between the sampling times and sampling sites. Water temperature (WT), oxidation-reduction potential (ORP), water transparency (SD), NO₃-N, and NH₃ significantly influenced bacterioplankton communities, and WT, SD, ORP, and NH₄-N significantly influenced eukaryoplankton communities in the river. These results implied that compared with the sampling sites, sampling times more significantly affected the bacterioplankton and eukaryoplankton river communities by influencing WT, ORP, SD, and nitrogen forms.

Detection of β-Lactamase-Producing Proteus mirabilis Strains of Animal Origin in Andhra Pradesh, India and Their Genetic Diversity

ABSTRACT

Proteus mirabilis is abundant in soil and water. Although this bacterium is part of the normal human intestinal flora, it can cause serious infections in humans, including complicated urinary tract infections. This pathogen is also commonly associated with multidrug resistance. In the present study, analysis of 1,093 samples from foods of animal origin and animal intestinal samples recovered 232 P. mirabilis isolates identified by PCR assay. Of these 232 isolates, 72 produced β-lactamase (determined by both phenotypic and genotypic methods), with the highest prevalence in poultry cloacal swabs (11.82%) followed by mutton (9.18%), khoa (6.32%), pork (5.63%), pig rectal swabs (5.52%), beef (5.45%), and chicken (5.13%) but none from sheep rectal swabs and bovine rectal swabs. Among β-lactamase genes, blaTEM was the predominant gene detected (59 isolates) followed by blaOXA (11 isolates), blaSHV (5 isolates), blaFOX (5 isolates), blaCIT (4 isolates), blaCTX-M1 and blaCTX-M9 (2 isolates each) and blaCTX-M2, blaDHA, and blaEBC (1 isolate each). None of the isolates carried blaACC, blaMOX, or carbapenemase genes (blaVIM, blaIMP, blaKPC, and blaNDM-1). Dendrogram analysis of enterobacterial repetitive intergenic consensus sequences and repetitive extragenic palindromic sequences obtained with PCR analysis of β-lactamase-producing isolates revealed 63 isolates, but 9 isolates did not yield bands. The analysis revealed that 6.58% of the samples had β-lactamase-producing P. mirabilis isolates that may affect food safety and contaminate the environment. Further genotyping revealed the genetic relationships between isolates of different origin. These findings emphasize the need for careful use of antibiotics to control the spread of β-lactamase-producing bacteria.

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