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International Journal of Environmental... Aug 2012This study assessed the antimicrobial susceptibility of 51 Listeria ivanovii and 33 Enterobacter cloacae strains isolated from various ready-to-eat foods sold in Alice,...
This study assessed the antimicrobial susceptibility of 51 Listeria ivanovii and 33 Enterobacter cloacae strains isolated from various ready-to-eat foods sold in Alice, South Africa. Isolates were identified using standard microbiological tests and further confirmed using API 20E and API Listeria kits. The disc diffusion technique was used to screen for antimicrobial susceptibility against 15 antimicrobials; minimum inhibitory concentration of five antibiotics was determined by the broth dilution method. All the strains of E. cloacae (100%) and 96% of L. ivanovii isolates were resistant to at least four or more of the antibiotics; nineteen antibiotypes were obtained based on the antibiotics used in the study. Antibiotype A5: AR PGR VAR ER APR was predominant in both L. ivanovii (23.5%) and E. cloacae (57.5%) isolates. Marked susceptibility of Listeria ivanovii was observed against chloramphenicol, ciprofloxacin, streptomycin and trimethoprim/sulfamethoxazole (100%) each while E. cloacae registered 100% susceptibility to ciprofloxacin only. Various percentages of susceptibility was reported to chloramphenicol and gentamicin (91%) each, nalidixic acid (97%) and streptomycin (94%). The MIC(90 )ranged from 0.004-7.5 µg/mL( )with E. cloacae being the most susceptible organism. The study demonstrated the presence of multi-resistant strains of bacteria in ready-to-eat-foods and speculates that these foods could serve as important vehicles transmitting multi-resistant bacteria to humans.
Topics: Bacteriological Techniques; Drug Resistance, Multiple, Bacterial; Enterobacter cloacae; Fast Foods; Food Microbiology; Listeria; Microbial Sensitivity Tests; South Africa
PubMed: 23202673
DOI: 10.3390/ijerph9093101 -
Journal of Food Protection Mar 2022Reference methods developed for detection of Listeria monocytogenes are commonly used for detection of Listeria at the genus level. Improved method performance data are...
Assessment of Reference Method Selective Broth and Plating Media with 19 Listeria Species Highlights the Importance of Including Diverse Species in Listeria Method Evaluations.
ABSTRACT
Reference methods developed for detection of Listeria monocytogenes are commonly used for detection of Listeria at the genus level. Improved method performance data are needed because this genus has expanded from 6 to 26 species and now includes several Listeria sensu lato species, which can have phenotypes distinct from those of Listeria sensu stricto. We evaluated growth of 19 Listeria species, including 12 recently described Listeria sensu lato species, using the media specified by (i) the U.S. Food and Drug Administration (FDA) Bacteriological Analytical Manual, (ii) the U.S. Department of Agriculture (USDA) Microbiology Laboratory Guidebook, and (iii) the International Organization for Standardization (ISO). The FDA broth enrichment procedure allowed all species to grow to detectable levels (≥4 log CFU/mL), yielded the highest mean growth (7.58 log CFU/mL), and was the only procedure with which no Listeria sensu lato species yielded significantly higher growth than did a comparison Listeria sensu stricto species. With the USDA and ISO broth enrichment procedures, several Listeria sensu lato species yielded significantly higher growth than did either Listeria seeligeri or Listeria ivanovii, suggesting that these two Listeria sensu stricto species could be outgrown by Listeria sensu lato species. On selective and differential agar media, L. seeligeri, L. ivanovii, and Listeria grayi produced colonies with atypical morphology and/or growth of these species was inhibited (which may lead to incorrect classification of a sample as negative), whereas several newly described Listeria sensu lato species grew to high levels and produced colonies with typical morphology. Overall, our study results indicate that the ability to detect various Listeria species can be impacted by the specific broth and selective and differential agar used. Our data can help guide selection of appropriate media and detection methods for environmental Listeria monitoring programs and methods that are most likely to detect the targeted Listeria groups (e.g., Listeria sensu stricto, which appear to be the most appropriate index organisms for the pathogen L. monocytogenes).
Topics: Culture Media; Food Microbiology; Listeria; Listeria monocytogenes
PubMed: 34855940
DOI: 10.4315/JFP-21-293 -
Poultry Science Apr 2014The aims of this study were to determine the prevalence and antimicrobial resistance of Listeria, Salmonella, and Yersinia spp. isolated from duck and goose intestinal...
The aims of this study were to determine the prevalence and antimicrobial resistance of Listeria, Salmonella, and Yersinia spp. isolated from duck and goose intestinal contents. A total of 471 samples, including 291 duck and 180 goose intestinal contents, were purchased from wet markets between November 2008 and July 2010. Listeria, Salmonella, and Yersinia spp. were isolated from 58 (12.3%), 107 (22.7%), and 80 (17%) of the samples, respectively. It was concluded that Listeria ivanovii, Salmonella Thompson, and Yersinia enterocolitica were the predominant serovars among Listeria, Salmonella, and Yersinia spp., respectively. Moreover, resistance to tetracycline was common in Listeria (48.3%) and Salmonella spp. (63.6%), whereas 51.3% of the Yersinia spp. isolates were resistant to cephalothin. Therefore, continued surveillance of the prevalence of the pathogens and also of emerging antibiotic resistance is needed to render possible the recognition of foods that may represent risks and also ensure the effective treatment of listeriosis, salmonellosis, and yersiniosis.
Topics: Animals; Anti-Bacterial Agents; Colony Count, Microbial; Drug Resistance, Bacterial; Ducks; Foodborne Diseases; Geese; Gram-Positive Bacterial Infections; Intestines; Iran; Listeria; Meat; Microbial Sensitivity Tests; Poultry Diseases; Prevalence; Salmonella; Salmonella Infections, Animal; Yersinia; Yersinia Infections
PubMed: 24706981
DOI: 10.3382/ps.2013-03699 -
Genome Announcements Jan 2015We present the complete genomes of Listeria ivanovii subsp. ivanovii WSLC 3010 (ATCC 19119(T)), Listeria ivanovii subsp. londoniensis WSLC 30151 (SLCC 8854), and...
We present the complete genomes of Listeria ivanovii subsp. ivanovii WSLC 3010 (ATCC 19119(T)), Listeria ivanovii subsp. londoniensis WSLC 30151 (SLCC 8854), and Listeria ivanovii subsp. londoniensis WSLC 30167 (SLCC 6032), representing the type strain of the species and two strains of the same serovar but different properties, respectively.
PubMed: 25614561
DOI: 10.1128/genomeA.01440-14 -
Molecules (Basel, Switzerland) Dec 2022The main target of this work is to discover new protein fractions from natural resources with high antibacterial action. The 7S and 11S globulin fractions, as well as...
The main target of this work is to discover new protein fractions from natural resources with high antibacterial action. The 7S and 11S globulin fractions, as well as the basic subunit (BS), were isolated from lupine seeds (), chemically characterized, and screened for antibacterial activity against seven pathogenic bacteria. SDS-PAGE revealed molecular weights ranging from 55 to 75 kDa for 7S globulin, 20-37 kD for 11S globulin, and 20 kD for the BS. 11S globulin and the BS migrated faster on Urea-PAGE toward the cathode compared to 7S globulin. FTIR and NMR showed different spectral patterns between the 7S and 11S globulins but similar ones between 11S globulin and the BS. The MICs of the BS were in the range of 0.05-2 μg/mL against , , , , , , and compared to higher values for 11S globulin. The BS surpassed 11S globulin in antibacterial action, while 7S globulin showed no effect. The MICs of 11S globulin and the BS represented only 5% and 2.5% of the specific antibiotic against , respectively. Scanning electron microscopy (SEM) demonstrated different signs of cellular deformation and decay in the protein-treated bacteria, probably due to interaction with the bacterial cell wall and membranes. 11S globulin and the BS can be nominated as effective food biopreservatives.
Topics: Lupinus; Globulins; Vegetables; Anti-Bacterial Agents; Seeds
PubMed: 36615230
DOI: 10.3390/molecules28010035 -
Microbes and Infection May 2023Two species of Listeria are pathogenic, Listeria monocytogenes and Listeria ivanovii. Although studies have shown that dairy ruminants shed Listeria spp. in feces, there...
Two species of Listeria are pathogenic, Listeria monocytogenes and Listeria ivanovii. Although studies have shown that dairy ruminants shed Listeria spp. in feces, there is little information about ruminants that do not shed Listeria spp. in their feces but asymptomatically carry them in organs. We evidence that ruminants can asymptomatically carry L. ivanovii in udders and L. monocytogenes and L. ivanovii in tonsils without fecal shedding. Whole-genome sequence of L. monocytogenes and L. ivanovii contained known core genes involved in virulence and antibiotic resistance. This work highlights tonsils and udders as a Listeria intra-host site of colonization.
Topics: Animals; Listeriosis; Mammary Glands, Animal; Spain; Palatine Tonsil; Listeria; Ruminants; Listeria monocytogenes; Genomics; Feces
PubMed: 36464197
DOI: 10.1016/j.micinf.2022.105079 -
Scientific Reports Jan 2020We have previously demonstrated that a recombinant Listeria ivanovii (LI) strain expressing the ESAT-6 or Ag85C protein of Mycobacterium tuberculosis (Mtb) as a...
We have previously demonstrated that a recombinant Listeria ivanovii (LI) strain expressing the ESAT-6 or Ag85C protein of Mycobacterium tuberculosis (Mtb) as a tuberculosis (TB) vaccine candidates induced antigen-specific cellular immune responses after intravenous immunization of mice. However, whether such recombinant strains could induce desired immune responses in the lung, where TB infection occurs, is not clear. In this paper, C57BL/6 J mice were intranasally vaccinated with attenuated LIΔactAplcB-Rv3875 (Δ refers to gene deletion in the bacterial genome) or LIΔactAplcB-Rv0129c, the two vaccine candidates that utilize LI as an antigen delivery vector. Bacterial load in the target organs, histological changes in the infected organs, the percentage of specific cytokine-secreting T cells in the lung and spleen, IgG levels in the serum and secretory IgA (SIgA) levles in bronchoalveolar lavage (BAL) fluid were determined at specific days post inoculation (dpi). The results showed that both strains were mainly confined to the lung and were eliminated at 10 dpi. The histological damage caused by the infection in the lung was slight and recovered by day 5. Intranasal vaccination of the mice twice at an interval of 4 weeks notably elicited TB antigen-specific CD4 and CD8 T cell responses in the lung and SIgA secretion in the pulmonary mucosa, and significantly enhanced the percentage of double-functional CD8 T cells (IFN-γ TNF-α CD8). To our knowledge, this is the first report regarding the used of LI vector vaccines to induce promising lung-localized cellular and humoral immune responses by intranasal vaccination. These data suggest that LI could be a novel and promising live vector to construct an intranasal vaccine against respiratory diseases.
Topics: Administration, Intranasal; Animals; Antigens, Bacterial; Bacterial Load; Bronchoalveolar Lavage Fluid; CD4-Positive T-Lymphocytes; CD8-Positive T-Lymphocytes; Female; Immunity, Cellular; Immunity, Humoral; Immunoglobulin A; Immunoglobulin G; Interferon-gamma; Listeria; Lung; Mice; Mice, Inbred C57BL; Tuberculosis Vaccines; Tumor Necrosis Factor-alpha; Vaccination
PubMed: 31942003
DOI: 10.1038/s41598-019-57245-6 -
Journal of Dairy Science Nov 1996Samples of caprine milk from bulk tanks of 405 farms in central Spain were analyzed for Listeria spp. once per season over a 1-yr period. Listeria monocytogenes and...
Samples of caprine milk from bulk tanks of 405 farms in central Spain were analyzed for Listeria spp. once per season over a 1-yr period. Listeria monocytogenes and Listeria innocua were detected in 2.56 and 1.73% of the 1445 samples, respectively. Listeria ivanovii (0.21% samples) and Listeria seeligeri (0.07% samples) were rarely isolated. Only 6 milk samples were contaminated by more than one Listeria species. Most farms (92.59%) produced milk that was apparently free from L. monocytogenes throughout the sampling period, and 88.40% produced milk that was apparently free from Listeria spp. Milk contamination by Listeria spp. was seasonal; incidence in autumn (9.33%) and winter (5.14%) samples was higher than incidence in spring (0.85%) and summer (0.85%) samples. Occurrence of Listeria spp. was lower in samples from mountain farms (1.25%) than in samples from plateau farms (7.03%).
Topics: Animals; Female; Goats; Listeria; Listeria monocytogenes; Milk; Seasons; Spain
PubMed: 8961100
DOI: 10.3168/jds.S0022-0302(96)76563-3 -
MBio Feb 2024Since 2010, the genus has had the addition of 22 new species that more than tripled the number of species identified until 2010. Sixteen of these 22 new species are... (Review)
Review
Since 2010, the genus has had the addition of 22 new species that more than tripled the number of species identified until 2010. Sixteen of these 22 new species are distantly related to the type species, , and several of these present phenotypes that distinguish them from classical species (, , , , and ). These 22 newly described species also show that is more genetically diverse than previously estimated. While future studies and surveys are needed to clarify the distribution of these species, at least some of these species may not be widely spread, while other species may be frequently found spread to human-related settings (e.g., farms and processing facilities), and others may be adapted to specific environmental habitats. Here, we review the taxonomic, phylogenetic, and ecological characteristics of these new species identified since 2010 and re-iterate the suggestion of re-classification of some species into three new genera: , , and . We also provide a review of current detection issues and the relevance to food safety related to the identification of these new species. For example, several new non-pathogenic species could be misidentified as the pathogen , based on methods that do not target -specific virulence genes/factors, leading to unnecessary product recalls. Moreover, eight species in the proposed new genus are not good indicators of environmental conditions that could allow to grow since species are unable to grow at low temperatures.
Topics: Humans; Phylogeny; Listeria; Listeria monocytogenes; Virulence Factors; Food Safety
PubMed: 38126771
DOI: 10.1128/mbio.00938-23 -
Revue Scientifique Et Technique... Sep 1991There is general agreement that listeriosis has a significant impact on Man as well as on animals. Listeria monocytogenes has been isolated from the faeces of healthy... (Review)
Review
There is general agreement that listeriosis has a significant impact on Man as well as on animals. Listeria monocytogenes has been isolated from the faeces of healthy human and animal carriers and from various environmental sources. L. monocytogenes is the pathogenic species most responsible for abortion, septicaemia and meningitis in animals and Man. Listeria ivanovii is a primary cause of abortion in animals. Owing to a number of epidemics and single cases caused by food contaminated with L. monocytogenes, listeriosis has received more attention in the past ten years than ever before. Entry of the organism into food-processing plants is primarily caused by animals which excrete Listeria in their faeces. Other sources of entry are raw foods of animal origin and personnel in food establishment. Proliferation of Listeria is promoted by high humidity and nutrient waste in certain food production plants. Removal of Listeria is almost impossible by routine disinfection. Listeria-contaminated sites pose a serious risk of recontamination of food-processing equipment and processed foods. Moreover, such sites represent an inexhaustible source of entry for Listeria in plant effluents. There is no denying that effluents from food-processing plants increase the spread of Listeria in the environment. However, considering the existence of other sources of entry, such as human and animal husbandry wastes, and that circulation and recontamination within the environment itself are also possible, this may not be a particularly important risk.
Topics: Animals; Food Microbiology; Food-Processing Industry; Humans; Listeria; Listeria monocytogenes; Listeriosis; Waste Disposal, Fluid
PubMed: 1782429
DOI: 10.20506/rst.10.3.567