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Scientific Reports Aug 2017Aeromonas sobria is opportunistic pathogen frequently found in environment and food. Interfering with its quorum sensing (QS) system could be a promising way to...
Aeromonas sobria is opportunistic pathogen frequently found in environment and food. Interfering with its quorum sensing (QS) system could be a promising way to alleviate its virulence. In this study, curcumin liposomes were prepared and their characteristics like particle size, zeta potential, PDI (Polymey Disperse Index), encapsulation efficiency and loading capacity were measured. The quorum sensing inhibitory effect of curcumin liposomes under sub-MIC (Minimum Inhibitory Concentration) on siderophore production, swimming and swarming motility, extracellular proteases, biofilm formation and AHLs (N-acylhomoserine lactones) production of A. sobria were also determined. The results showed that, the curcumin liposomes with high encapsulation capacity (84.51 ± 0.58%) were stable and homogeneous. QS-regulated phenotypes of the pathogen were significantly inhibited by curcumin liposomes. The in silico analysis revealed that the QS system of A. sobria may be inhibited by released curcumin from curcumin liposomes through interacting with the built LuxI type protein and blocking the production of AHLs.
Topics: Acyl-Butyrolactones; Aeromonas; Amino Acid Sequence; Bacterial Proteins; Biofilms; Curcumin; Liposomes; Microbial Sensitivity Tests; Microscopy, Electron, Scanning; Molecular Docking Simulation; Particle Size; Protein Binding; Protein Conformation; Quorum Sensing; Sequence Homology, Amino Acid
PubMed: 28819178
DOI: 10.1038/s41598-017-08986-9 -
Journal, Genetic Engineering &... Oct 2021Mining for precious metals is detrimental to the composition of soil structure and microbial diversity distribution and is a health risk to human communities around the...
BACKGROUND
Mining for precious metals is detrimental to the composition of soil structure and microbial diversity distribution and is a health risk to human communities around the affected communities. This study was aimed at determining the physical and chemical characteristics and diversity of bacteria in the soil of local mining sites for biosorption of heavy metals.
RESULTS
Results of physical and chemical characteristics showed mean pH values and percentage organic carbon to range from 7.1 to 8.2 and 0.18 to 1.12% respectively with statistical significance between sampling sites (P ≤ 0.05). Similarly, cation exchange capacity, electrical conductivity, moisture, total nitrogen, and carbon/nitrogen ratio (C:N) in the soil ranged between 1.52 to 3.57 cmol/kg, 0.15 to 0.32 ds/m, 0.14 to 0.82%, 0.10 to 0.28%, and 1.7 to 4.8 respectively. The highest heavy metal concentration of 59.01 ppm was recorded in soils obtained from site 3. The enumeration of viable aerobic bacteria recorded the highest mean count of 4.5 × 10 cfu/g observed at site 2 with statistical significance (P ≤ 0.05) between the sampled soils. Alcaligenes faecalis strain UBI, Aeromonas sp. strain UBI, Aeromonas sobria, and Leptothrix ginsengisoli that make up 11.2% of total identified bacteria were able to grow in higher amended concentrations of heavy metals. The evolutionary relationship showed the four heavy metal-tolerant bacteria identified belonged to the phylum Proteobacteria of class Betaproteobacteria in the order Burkholderiales. Heavy metal biosorption by the bacteria showed Alcaligenes faecalis strain UBI having the highest uptake capacity of 73.5% for Cu.
CONCLUSION
In conclusion, Alcaligenes faecalis strain UBI (MT107249) and Aeromonas sp. strain UBI (MT126242) identified in this study showed promising capability to withstand heavy metals and are good candidates in genetic modification for bioremediation.
PubMed: 34633566
DOI: 10.1186/s43141-021-00251-x -
Food Safety (Tokyo, Japan) Jun 2021Colistin (CST) is considered the last resort for the treatment of infectious diseases due to multidrug-resistant bacteria. Since the r-1 gene has been reported in...
Colistin (CST) is considered the last resort for the treatment of infectious diseases due to multidrug-resistant bacteria. Since the r-1 gene has been reported in isolated from food, animals, and humans in China, the prevalence of CST-resistant bacteria has been of great concern. Here, we investigated the prevalence of CST resistance and plasmid-mediated colistin-resistance genes () in gram-negative bacteria isolated among retail meats in Japan. CST-resistant bacteria were isolated from 310 domestic retail meats (103 chicken meat, 103 pork, and 104 beef) purchased between May 2017 and July 2018 from retail shops in Japan using CST-containing media and antimicrobial susceptibility testing. The gene was investigated in isolates with a CST minimum inhibitory concentration of ≥1 μg/mL. Excluding the intrinsically CST-resistant isolates, CST-resistant bacteria were isolated from 39 of the total chicken meats (37.9%), 19 of the pork samples (18.4%), and 18 of the beef samples (17.3%). A total of 459 isolates were identified, out of which 99 were CST-resistant. CST resistance (resistance breakpoints: , >4 μg/mL; others, >2 μg/mL) was found in spp. (48/206, 23.3%), spp. (5/112, 4.5%), (23/39, 59%), spp. (4/26, 15.4%), spp. (2/23, 8.7%), spp. (2/16, 12.5%), spp. (7/14, 50%), spp. (1/8, 12.5%), spp. (5/7, 71.4%), spp. (1/4, 25%), and spp. (1/2, 50%). The gene was detected in 16 isolates: -1 in 14 isolates of from 10 chicken samples (9.7%), and -3 in two isolates of from pork and chicken samples (each 1.0%). The findings of this study highlight the necessity of surveillance of CST resistance and resistance genes in bacteria that contaminate retail meats.
PubMed: 34249589
DOI: 10.14252/foodsafetyfscj.D-21-00002 -
Frontiers in Immunology 2021Bacterial infection presents severe challenge to tilapia farming, which is largely influenced by water temperature. However, how water temperature determines tilapias'...
Bacterial infection presents severe challenge to tilapia farming, which is largely influenced by water temperature. However, how water temperature determines tilapias' survival to infection is not well understood. Here, we address this issue from the perspective of metabolic state. Tilapias were more susceptible to infection at 33°C than at 18°C, which is associated with differential metabolism of the fish. Compared to the metabolome of tilapia at 18°C, the metabolome at 33°C was characterized with increased an tricarboxylic acid cycle and a reduced level of -inositol which represent the most impactful pathway and crucial biomarker, respectively. These alterations were accompanied with the elevated transcriptional level of 10 innate immune genes with infection time, where , , , and exhibited a higher expression at 33°C than at 18°C and was attenuated by exogenous -inositol in both groups. Interestingly, exogenous -inositol inactivated the elevated TCA cycle inhibiting the enzymatic activity of succinate dehydrogenase and malate dehydrogenase. Thus, tilapias showed a higher survival ability at 33°C. Our study reveals a previously unknown relationship among water temperature, metabolic state, and innate immunity and establishes a novel approach to eliminate bacterial pathogens in tilapia at higher water temperature.
Topics: Animals; Biomarkers; Disease Resistance; Energy Metabolism; Fish Diseases; Host-Pathogen Interactions; Immunity, Innate; Inositol; Metabolome; Metabolomics; Temperature; Tilapia; Water
PubMed: 34566956
DOI: 10.3389/fimmu.2021.682724 -
Environmental Research Apr 2023The global decline in amphibian populations is a major environmental issue. Chytridiomycosis, Ranaviruses and the red-leg syndrome have been identified in unusual...
The global decline in amphibian populations is a major environmental issue. Chytridiomycosis, Ranaviruses and the red-leg syndrome have been identified in unusual mortality events. However, these infections do not account for all causes of declining amphibian populations. Moreover, several cases of amphibian mortality are difficult to solve without resorting to an interdisciplinary approach. Two cases of unusual mortality in Rana temporaria occurred at two high-mountain ponds (northwest Italy) in April and May 2021. Water and frog samples were analysed to understand the possible causes responsible for the unusual mortalities. Results of the main physicochemical (pH, conductivity, dissolved oxygen, chemical and biochemical oxygen demand) and nutrient (ammonia/ammonium, nitrite, nitrate, total phosphorus) parameters revealed a good condition of the water quality, with the absence of the main cyanotoxins (microcystins/nodularins). However, unseasonably high spring water temperatures were recorded in both ponds (12.73 °C and 14.21 °C for Frog Pond and Selleries Pond, respectively). Frogs (n = 50; snout-vent length: 7.0-9.8 cm; body mass: 85-123 g) collected from Frog Pond mainly presented bumps on the ventral cavity and dermal ulceration associated with the isolation of Carnobacterium maltaromaticum. On the other hand, frogs (n = 5; snout-vent length: 8.0-9.1 cm; body mass: 87-92 g) from Selleries Pond presented petechiae and dermal ulcerations on the rear limbs associated with the isolation of Aeromonas salmonicida and A. sobria. In both mortality events, the interdisciplinary approach revealed an association between frog mortalities and the isolation of bacteria. Isolated bacteria are considered opportunistic pathogens, and the high values of the water temperature has certainly led a stress on the frogs, favouring the spread of bacteria and the death of the frogs. Further studies are needed to assess the pathophysiological effects of the opportunistic bacteria here isolated, clarifying the interactions between emerging pathogens and climate change.
Topics: Animals; Rana temporaria; Ponds; Climate Change; Amphibians; Ranavirus
PubMed: 36736753
DOI: 10.1016/j.envres.2023.115411 -
Anais Da Academia Brasileira de Ciencias 2021In this study, it was determinated the essential oil of cultivated apple mint, Mentha suaveolens Ehrh. composition and in vitro antibacterial activity of against 11 fish...
In this study, it was determinated the essential oil of cultivated apple mint, Mentha suaveolens Ehrh. composition and in vitro antibacterial activity of against 11 fish pathogen bacteria including Gram-positive (Staphylococcus warneri, Staphylococcus sp., Lactococcus garvieae, Vagococus salmoninarum) and Gram-negative (Aeromonas hydrophila, Aeromonas sobria Aeromonas cavieae, Vibrio anguillarum, Pseudomonas aeroginosa, Yersinia ruckeri, Edwardsiella tarda) by using agar diffusion assay. The main component of M. suaveolence oil was obtained as piperitenone oxide. The essential oil exhibited strong inhibitory activity such as inhibition zone sizes: 30-50mm at 250-1000 µL mL-1 concentrations against V. anguillarum; 16-20mm at 31.25-125 µL mL-1 concentrations against P. aeroginosa; 15-18mm at 500-1000 µL mL-1 concentrations against A. sobria. However, it was found to be moderately effective against E. tarda (8-15 mm), Y. ruckeri (9-12mm), S. warneri (9-10mm), V. salmoninarum (9mm) and Staphylococcus sp. (8-9mm). The essential oil showed weak inhibitory activity against A. cavieae (5-8), A. hydrophila (6-7mm), L. garvieae (5-7mm). Thus, effect of essential oil of M. suaveolens on immune response and disease resistance against Vibrio anguillarum, A. sobria and P. aeroginosa should be investigated in vivo in cultured fish species in future studies.
Topics: Aeromonas; Animals; Anti-Bacterial Agents; Fish Diseases; Lactococcus; Mentha; Oils, Volatile; Staphylococcus; Vibrio
PubMed: 34468488
DOI: 10.1590/0001-3765202120190478 -
Archives of Razi Institute Dec 2021The current study aimed to isolate and identify the bacteria associated with burn wounds and investigate the antimicrobial susceptibility pattern against a group of most...
The current study aimed to isolate and identify the bacteria associated with burn wounds and investigate the antimicrobial susceptibility pattern against a group of most commonly prescribed antibiotics. In total, 105 burn wound swabs were collected from burn patients admitted to the burn unit of Al-Sadr Teaching Hospital in Misan City, Iraq. The swabs had been cultured on different media; the colonies were diagnosed based on the phenotypic and culture characteristics. The bacteria were identified through cultural characters and Gram staining diagnosed by VITEK 2 Compact Automated Systems. In total, there were nine distinct bacterial isolations, of which, was the most common pathogen [20%] followed by [17.14%], .[16.19%], [13.33%], [10.47%], [7.6%], [6.6%], and at last, and , which had the same percentage [4.7%]. Most isolates showed high resistance to Tobramycin, Trimethoprim, Cephalothin, and Imipenem while isolates mostly had high susceptibility to Amikacin, Cefotaxime, and Ciprofloxacin. Wound burn infection still represents a serious problem for burn patients with many bacteria developing different degrees of resistance to most known antibiotics.
Topics: Anti-Bacterial Agents; Bacteria; Iraq; Microbial Sensitivity Tests; Pseudomonas aeruginosa; Humans
PubMed: 35546990
DOI: 10.22092/ari.2021.356367.1833 -
Veterinaria Italiana 2015The rapid rise in the number of pet chelonians and their illegal trade can modify the ecology, involving exotic pets, humans, and microbiological agents. Therefore,...
The rapid rise in the number of pet chelonians and their illegal trade can modify the ecology, involving exotic pets, humans, and microbiological agents. Therefore, different epidemiological situations and the related risk to introduce and spread infectious diseases, especially zoonotic agents, have to be considered. The aim of this study was to investigate the microbiological and parasitological situation in 2 chelonian facilities (a private breeding of tortoises and a shelter for turtles) collecting oral/cloacal swabs and cloacal flushes to research viruses, bacteria, and parasites. No Chelonian Herperviruses, Cryptosporidium spp., and Giardia spp. infections were found. Salmonella spp. were detected in 8% of tortoises and in 37.5% of turtles and oxyurid eggs in 23.7% of tortoises and 15% of turtles; ascarid eggs were present only in tortoises. Moreover, 6 turtles showed cutaneous lesions, where Aeromonas sobria was isolated as main pathogen. Further studies should be performed to understand the zoonotic and infectious risk in each chelonian facility and to characterize the variables that could influence the microbiological patterns.
Topics: Animals; Italy; Turtles
PubMed: 26344661
DOI: 10.12834/VetIt.7.21.3 -
Frontiers in Veterinary Science 2022The pharmacokinetics and tissue distribution of enrofloxacin were determined in Yellow River carp () reared at 20°C after single oral administration of enrofloxacin at...
The pharmacokinetics and tissue distribution of enrofloxacin were determined in Yellow River carp () reared at 20°C after single oral administration of enrofloxacin at 10 mg·kg body weight (BW). Plasma, bile, and different tissue samples, including liver, kidney, gill, gut, and skin-muscle, were collected at predetermined times points. An HPLC method was developed to simultaneously determine the concentrations of enrofloxacin and its metabolite, ciprofloxacin. However, ciprofloxacin was only detectable in some liver samples with trace levels. Then the average enrofloxacin concentrations vs. time data were subjected to a non-compartmental analysis using WinNonLin 5.2 software. Multiple peaking profiles were observed in all enrofloxacin concentration-time curves. The peak concentration (C) values were observed as 0.79, 1.01, 2.09, 2.85, 4.34, 10.78, and 13.07 μg·ml (or g) in plasma, skin-muscle, gill, kidney, liver, bile, and gut, respectively, and the corresponding time to reach peak concentration (T) was 8, 8, 1, 8, 1, 72, and 4 h, respectively. The values of elimination half-life (T ) of enrofloxacin in different tissues was in the following order: gill (291.13 h) > liver (222.29 h) > kidney (157.22 h) > plasma (129.44 h) > gut (91.47 h) > skin-muscle (87.77 h) > bile (86.22 h). The present results showed that enrofloxacin had a wide distribution in different tissues, however slow absorption and elimination in Yellow River carp. Additionally, enrofloxacin exhibited large distribution in bile, indicating that bile excretion might be the primary elimination route of enrofloxacin in Yellow River carp. A withdrawal period was calculated as 379.2 °C-day for single oral dosing of enrofloxacin at 10 mg/kg BW. Based on the calculated PK/PD indices of AUC/MIC or C/MIC, the current enrofloxacin dosing regimen might have a positive therapeutic effect on the infection of , or . However, the depletion study following multiple oral doses should be carried out in Yellow River carp reared at lower temperatures, and the withdrawal period should also be further calculated.
PubMed: 35187147
DOI: 10.3389/fvets.2022.822032 -
Aquatic Biosystems 2014Seabirds have been historically used to monitor environmental contamination. The aim of the present study was to test the suitability of a species belonging to the...
INTRODUCTION
Seabirds have been historically used to monitor environmental contamination. The aim of the present study was to test the suitability of a species belonging to the Procellariiformes group, the Manx shearwater, Puffinus puffinus, as a sentinel of environmental health, by determining contaminant levels (trace metals and organochlorine compounds) from carcass tissues and by isolating Vibrio spp. and Aeromonas spp. from live specimens. To this end, 35 Puffinus puffinus carcasses wrecked on the north-central coast of the state of Rio de Janeiro, Brazil, and two carcasses recovered in Aracruz, on the coast of the state of Espírito Santo, Brazil, were sampled, and fragments of muscle and hepatic tissues were collected for contaminant analyses. Swabs from eleven birds found alive at the north-central coast of Rio de Janeiro were collected for isolation of the aforementioned bacteria.
RESULTS
THE AVERAGE CONCENTRATION IN DRY WEIGHT (DW) OF THE TRACE METALS WERE: mercury 7.19 mg kg(-1)(liver) and 1.23 mg kg(-1) (muscle); selenium 34.66 mg kg(-1) (liver) and 7.98 mg kg(-1) (muscle); cadmium 22.33 mg kg(-1) (liver) and 1.11 mg kg(-1) (muscle); and lead, 0.1 mg kg(--1) (liver) and 0.16 mg kg(-1) (muscle). Organochlorine compounds were detected in all specimens, and hexachlorbiphenyls, heptachlorbiphenyls and DDTs presented the highest levels. Regarding microbiological contamination, bacteria from the Vibrio genus were isolated from 91% of the analyzed specimens. Vibrio harveyi was the predominant species. Bacteria from the Aeromonas genus were isolated from 18% of the specimens. Aeromonas sobria was the only identified species.
CONCLUSIONS
The results indicate that Puffinus puffinus seems to be a competent ocean health sentinel. Therefore, the monitoring of contaminant levels and the isolation of public health interest bacteria should proceed in order to consolidate this species importance as a sentinel.
PubMed: 25191536
DOI: 10.1186/2046-9063-10-6