-
International Journal of Systematic and... Jul 2023During our studies on spoilage microbiomes of modified atmosphere packaged broiler meat, we isolated three strains (PNs007, STAA11 and STAA25) of unknown identity. In...
During our studies on spoilage microbiomes of modified atmosphere packaged broiler meat, we isolated three strains (PNs007, STAA11 and STAA25) of unknown identity. In this present polyphasic taxonomy study, including genome-based analyses, we discovered that these isolates represent two novel species belonging to the genus . In all phylogenetic analyses, PNs007 was positioned very close to but both the average nucleotide identity (ANI; 89.5 %) and digital DNA-DNA hybridization (dDDH; 38.3 %) values distinguished it as a novel vagococcal species. STAA11 and STAA25 were genetically highly similar (16S rRNA, ANI and dDDH 100 %). The phylogenetic position of STAA11 was adjacent to but out of the cluster containing , and PNs007. According to the ANI (76.2-76.4 %) and dDDH (<22.6 %) values it also represented a novel vagococcal species. Phenotypic characteristics and chemotaxonomic properties of both novel species were typical for vagococci and they contained C (25.5-30.1 %) and C ω9 (67.3-73.0 %) as the major cellular fatty acids. The streptomycin-resistant genotype of STAA11 and STAA25 allowing the growth on streptomycin thallous acetate actidione medium was considered to result from a modification in codon 104 of the gene leading to P104A substitution. The ability of STAA11 and STAA25 to produce ammonia from arginine separated them from PNs007, which did not show arginine deiminase activity. We propose the names sp. nov. (type strain PNs007=DSM 115185=CCUG 76696) and sp. nov. (type strain STAA11=DSM 115183=CCUG 76697) for these novel species.
Topics: Animals; Fatty Acids; Phylogeny; RNA, Ribosomal, 16S; Base Composition; Sequence Analysis, DNA; DNA, Bacterial; Bacterial Typing Techniques; Chickens; Meat; Enterococcaceae; Nucleic Acid Hybridization; Atmosphere
PubMed: 37462470
DOI: 10.1099/ijsem.0.005963 -
Foods (Basel, Switzerland) Jun 2023In this study, the quality (sensory evaluation, microbial enumerate, color, tvb-n (total volatile basic nitrogen), tca-soluble peptide (trichloroacetic acid-soluble...
In this study, the quality (sensory evaluation, microbial enumerate, color, tvb-n (total volatile basic nitrogen), tca-soluble peptide (trichloroacetic acid-soluble peptide), muscle glucose, lactate, total sugar, Bas (Biogenic amines), VOCs (volatile organic compounds) and the microbial dynamic structure in samples stored at 4 °C were evaluated, and the relationship between VOCs and the diversity structure of microorganisms was also discussed. It was determined by sensory evaluation that the shelf life of samples was around 8 days. Protein and sugar were detected in large quantities by microorganisms in the later stage. At the same time, this also caused a large amount of Bas (biogenic amines) (tyramine, cadaverine, and putrescine). According to high-throughput amplicon sequencing, the initial microbiota of samples was mainly composed of , , , , , , , and . Among them, was the most advantageous taxon of samples at the end of the shelf life. The minor fraction of the microbial consortium consisting of , and was detected. The substances 3-methyl-1-butanol, ethyl acetate, and acetone were the main volatile components. The glucose, lactic acid, and total sugar were negatively correlated with , , , and ; the proportion of these microorganisms was relatively high in the early stage. TVB-N and TCA-soluble peptides were positively correlated with , , , , and , and these microorganisms increased greatly in the later stage. The substance 3-methyl-1-butanol was positively correlated with and negatively correlated with . Ethyl acetate was associated with , and . Acetone was positively correlated with .
PubMed: 37444217
DOI: 10.3390/foods12132479 -
3 Biotech Aug 2023In the present study, attempts have been made to isolate reductive acetogens from the rumen fluid samples of Murrah buffaloes (). Out of 32 rumen samples 51 isolates...
In the present study, attempts have been made to isolate reductive acetogens from the rumen fluid samples of Murrah buffaloes (). Out of 32 rumen samples 51 isolates were isolated, and based on autotrophic growth for production of acetate and presence of formyltetrahydrofolate synthetase gene (FTHFS) 12 isolates were confirmed as reductive acetogens. Microscopic observations showed that ten isolates as Gram-positive rods (ACB28, ACB29, ACB66, ACB73, ACB81, ACB91, ACB133, ACB229, ACB52, ACB95) and two isolates as Gram-positive cocci (ACB19, ACB89). All isolates tested negative for catalase, oxidase, and gelatin liquefaction, whereas the production of HS was detected for two (ACB52 and ACB95) of the above isolates. All these isolates showed autotrophic growth from H and CO, and heterotrophic growth with different fermentable sugars, viz., d-glucose, D-fructose, and D-trehalose but failed to grow on salicin, raffinose, and l-rhamnose. Out of the isolates, two showed amylase activity (ACB28 and ACB95), five showed CMCase activity (ACB19, ACB28, ACB29, ACB73 and ACB91), three showed pectinase activity (ACB29, ACB52 and ACB89), whereas none of the isolates was found positive for avicellase and xylanase activity. Based on 16S rDNA gene sequence analysis, the isolates showed their phylogenetic relationship with maximum similarity up to 99% to different strains of earlier reported known acetogens of clostridia group including sp. (6), (1), sp. (1) and (1) except one, i.e., . The results indicate that reductive acetogens isolated from the rumen fluid samples of Murrah buffalos are both autotrophic and heterotrophic in nature and further investigations are required to exploit and explore their potential as an alternate hydrogen sink.
PubMed: 37415727
DOI: 10.1007/s13205-023-03688-8 -
Frontiers in Microbiology 2023Linezolid is a critically important oxazolidinone antibiotic used in human medicine. Although linezolid is not licensed for use in food-producing animals, the use of...
BACKGROUND
Linezolid is a critically important oxazolidinone antibiotic used in human medicine. Although linezolid is not licensed for use in food-producing animals, the use of florfenicol in veterinary medicine co-selects for oxazolidinone resistance genes.
OBJECTIVE
This study aimed to assess the occurrence of , and in florfenicol-resistant isolates from beef cattle and veal calves from different herds in Switzerland.
METHODS
A total of 618 cecal samples taken from beef cattle and veal calves at slaughter originating from 199 herds were cultured after an enrichment step on a selective medium containing 10 mg/L florfenicol. Isolates were screened by PCR for , and which are genes known to confer resistance to oxazolidinones and phenicols. One isolate per PCR-positive species and herd was selected for antimicrobial susceptibility testing (AST) and whole-genome sequencing (WGS).
RESULTS
Overall, 105 florfenicol-resistant isolates were obtained from 99 (16%) of the samples, corresponding to 4% of the beef cattle herds and 24% of the veal calf herds. Screening by PCR revealed the presence of in 95 (90%) and in 22 (21%) of the isolates. None of the isolates contained . Isolates included for AST and WGS analysis were (.) ( = 14), ( = 12), ( = 1), ( = 2), ( = 1), (.) ( = 2), (.) ( = 1), and (.) ( = 1). Thirteen isolates exhibited phenotypic linezolid resistance. Three novel OptrA variants were identified. Multilocus sequence typing identified four ST18 belonging to hospital-associated clade A1. There was a difference in the replicon profile among and -harboring plasmids, with rep9 (RepA_) plasmids dominating in -harboring and rep2 (Inc18) and rep29 (Rep_3) plasmids in -carrying .
CONCLUSION
Beef cattle and veal calves are reservoirs for enterococci with acquired linezolid resistance genes and . The presence of ST18 highlights the zoonotic potential of some bovine isolates. The dispersal of clinically relevant oxazolidinone resistance genes throughout a wide variety of species including spp., , and the probiotic in food-producing animals is a public health concern.
PubMed: 37389336
DOI: 10.3389/fmicb.2023.1150070 -
International Journal of Microbiology 2023Zambia has seen rapid development in aquaculture, and in recent years, the industry has experienced disease outbreaks where fish have increasingly become a potential...
Zambia has seen rapid development in aquaculture, and in recent years, the industry has experienced disease outbreaks where fish have increasingly become a potential contributor to emerging bacterial zoonotic diseases. The aim of this study was to identify bacterial pathogens with zoonotic potential in apparently healthy fish and water from their habitat. A total of sixty-three fish were sampled, and fifty-nine water samples were collected from the habitats of these fish. Bacteria were cultured from the internal organs of fish and water, and these were identified through standard bacteriological methods comprising morphological characterization, Gram-staining, and a panel of biochemical tests. The following bacterial pathogens with zoonotic potential were identified at a farm prevalence of (13.2%), (2.1%), (2.1%), (0.7%), (6.9%), (2.1%), (0.7%), (18.1%), and (0.7). Other bacteria with varying significance as fish pathogens identified included (2.1%), (1.4%), (1.4%), (2.1%), (10.4%), (3.5%), (1.4%), (1.4%), (2.1%), (4.2%), (6.9%), (1.4%), (1.4%), (6.3%), (1.4%), (1.4%), (0.7%), and (0.7%). The current study provides baseline information for future reference and the implementation of public health guidelines with regard to potential zoonotic diseases in fish.
PubMed: 37333886
DOI: 10.1155/2023/6650378 -
BioRxiv : the Preprint Server For... May 2023Beetles are ubiquitous cave invertebrates worldwide that adapted to scarce subterranean resources when they colonized caves. Here, we investigated the potential role of...
Beetles are ubiquitous cave invertebrates worldwide that adapted to scarce subterranean resources when they colonized caves. Here, we investigated the potential role of gut microbiota in the adaptation of beetles to caves from different climatic regions of the Carpathians. The beetles' microbiota was host-specific, reflecting phylogenetic and nutritional adaptation. The microbial community structure further resolved conspecific beetles by caves suggesting microbiota-host coevolution and influences by local environmental factors. The detritivore species hosted a variety of bacteria known to decompose and ferment organic matter, suggesting turnover and host cooperative digestion of the sedimentary microbiota and allochthonous-derived nutrients. The cave Carabidae, with strong mandibulae adapted to predation and scavenging of animal and plant remains, had distinct microbiota dominated by symbiotic lineages or . All beetles had relatively high levels of fermentative and involved in lipid accumulation and a reduction of metabolic activity, and both features characterize adaptation to caves.
PubMed: 37214959
DOI: 10.1101/2023.05.12.540564 -
Animals : An Open Access Journal From... Apr 2023Doxycycline is a therapeutic veterinary antibiotic commonly used in pig breeding. In this study, 27 fattening pigs of 33.5 ± 0.72 kg were divided equally into 3 groups....
Doxycycline is a therapeutic veterinary antibiotic commonly used in pig breeding. In this study, 27 fattening pigs of 33.5 ± 0.72 kg were divided equally into 3 groups. Doxycycline at 0, 3, and 5 mg/kg body weight was added to the feed in groups CK, L and H. The medication and withdrawal periods were set at 5 and 28 days. The results showed that the doxycycline average concentrations in groups L and H during the medication period were 117.63 ± 13.54 and 202.03 ± 24.91 mg/kg dry matter, respectively. Doxycycline levels were lower than the detection limit after 20 days. Doxycycline did not affect the diversity of the intestinal microbial community structure. The relative abundances of were significantly higher in treatment groups than that in group CK, and , , , and abundances were significantly positively correlated with doxycycline concentration. Interestingly, the microbiota cooccurrence network suggested that high doxycycline concentration weakened the interactions among bacteria until day 33. Functional prediction showed that doxycycline significantly altered metabolic pathways related to the cell membrane. The results revealed that the use of doxycycline during pig breeding can affect bacterial abundance during the withdrawal period, and it may affect interactions among bacteria and change the intestinal metabolic pathways.
PubMed: 37106856
DOI: 10.3390/ani13081293 -
PeerJ 2023Sodium hypochlorite is generally used as a disinfectant in washing of freshwater fishes where the safety aspect of health is of concern. Although plant-based essential...
Sodium hypochlorite is generally used as a disinfectant in washing of freshwater fishes where the safety aspect of health is of concern. Although plant-based essential oils and synthetic chemical agents have been applied, they might contain toxic substances, are expensive and can cause undesirable quality. This research aims to fill the knowledge gap necessary to validate juice as a disinfecting agent for preserving striped catfish steaks at -20 °C for 28 days. Fifty (50) ppm sodium hypochlorite was used as a commercial disinfectant (control). The results showed that a negative color characteristic (higher a* and increased b*) was found in the control but not in striped catfish steaks immersed in juice (TM) on days 14 and 28. No significant differences were found in the peroxide value among the treatments on days 14 and 28 ( > 0.05). A lower accumulation of trichloroacetic acid soluble peptides was detected in TM but not in control, while total volatile basic nitrogen of all treatments was up to standard of fish quality during storage. Contrastingly, the total viable count of both treatments increased to >7.0 log CFU/g on day 28 which did not meet the edible limit of standard for freshwater fishes. The spoilage microbial community was observed on days 0 and 28 of storage which showed a decrease in relative abundance of , and as found in TM on day 28, when compared to the control. Thus, these results implied that juice could replace sodium hypochlorite as an alternative disinfecting agent to control the microbiological spoilage and physico-chemical quality of striped catfish steaks.
Topics: Animals; Sodium Hypochlorite; Catfishes; Disinfectants; Plant Oils; Citrus
PubMed: 37065691
DOI: 10.7717/peerj.15168 -
Frontiers in Pharmacology 2023Non-alcoholic fatty liver disease (NAFLD) has gradually become the primary cause of fatty liver disease. Betel nuts have been used to treat gastrointestinal diseases....
Non-alcoholic fatty liver disease (NAFLD) has gradually become the primary cause of fatty liver disease. Betel nuts have been used to treat gastrointestinal diseases. In the present study, we analyzed the pathology, serology, gut flora, and metabolites in a rat model of NAFLD, with and without betel nut alkaloid treatment, using an integrated approach involving pathology, serological testing, 16S rRNA gene sequencing, and ultra-performance liquid chromatography-mass spectrometry metabolomics. Two rats were used for model validation. Thirty SD rats were included and divided into the normal group (C group), NAFLD model group (M group), low-dose group, medium-dose group (T group), and high-dose group with intraperitoneal injection of arecoline. The expression of blood lipids was significantly downregulated at all three arecoline concentrations ( < 0.05). Alpha-diversity analysis of the intestinal flora showed significant differences among the three groups, with a significant reduction in population diversity in the M group and a recovery of population diversity after arecoline treatment. At the phylum level, the relative abundance of was significantly higher in the T group and in the M group. The KEGG metabolic pathways included polyketide sugar unit biosynthesis and hypertrophic cardiomyopathy. Thirty-three significantly different metabolites were identified among the groups. Significantly different metabolites between groups T and M included indolepyruvate, 2-deoxystreptamine, sakuranetin, glycyl-leucine, and riboflavin. The KEGG metabolic pathway suggested a potential role for arachidonic acid metabolism, serotonergic synapses, neuroactive ligand-receptor interactions, tyrosine metabolism, and regiomelanin. Vitamin digestion and absorption, as well as regulation of lipolysis in adipocytes, were the main metabolic pathways that distinguished the T vs. M groups. PGE2 is involved in several metabolic pathways. Correlation analysis showed that 29 bacterial species were significantly associated with PGE2 levels in the M and T groups. , , , unidentified , unidentified , and five other bacterial groups are unique in the PGE2 metabolic pathway regulated by arecoline. Arecoline has lipid-lowering effects and may exert therapeutic effects in NAFLD through intestinal metabolites and intestinal flora, as well as through the //-COX2/PGE2 pathway. Thus, arecoline may represent a potential drug or target for NAFLD treatment.
PubMed: 37050898
DOI: 10.3389/fphar.2023.1132026 -
Journal of Agricultural and Food... Apr 2023Germs associated with insect eggs can profoundly mediate interactions between host plants and herbivores, with the potential to coordinate plant physiological reactions...
Germs associated with insect eggs can profoundly mediate interactions between host plants and herbivores, with the potential to coordinate plant physiological reactions with cascading effects on insect fitness. An experimental system was established including the oriental fruit fly (OFF, ) and tomato to examine the functions of egg-associated germs in mediating plant-herbivore interactions. OFF feeding resulted in significantly increased tannins, flavonoids, amino acids, and salicylic acid in the host tomato. These defensive responses of tomato were induced by the egg-associated germs, including , , and sp. Tannins and flavonoids had no significant feedback effects on the pupal weight of OFF, while pupal biomass was significantly decreased by tannins and flavonoids in the germ-free treatment. Metabolome analysis showed that OFF mainly induced metabolic changes in carboxylic acid derivatives. Phenylalanine significantly induced downstream metabolic changes associated with phenylpropanoid accumulation. Finally, we conclude that the effects of egg-associated germs played an important role in facilitating OFF population adaptation and growth by mediating plant defenses, which provides a new paradigm for exploring the interaction of plant-pest and implementing effective pest biocontrol.
PubMed: 37021960
DOI: 10.1021/acs.jafc.3c00427