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Journal of Hand Surgery Global Online Mar 2023Necrotizing fasciitis is a soft-tissue infection associated with significant morbidity and mortality. The bacteria most associated with necrotizing fasciitis include...
Necrotizing fasciitis is a soft-tissue infection associated with significant morbidity and mortality. The bacteria most associated with necrotizing fasciitis include (group A), species, species, and species. (), formerly known as , is a halophilic, gram-negative bacillus known to infect marine organisms in warm coastal waters. Necrotizing fasciitis associated with has been reported to have higher rates of serious complications and mortality because of an atypical presentation and a rapidly progressive course. This report presents a case of successfully treated necrotizing fasciitis of the upper extremity and the nuances of management that led to a favorable outcome in which the patient was discharged for home without complications.
PubMed: 36974285
DOI: 10.1016/j.jhsg.2022.10.004 -
RSC Advances Mar 2023In this work, a visible light-driven La/TiO@g-CN photocatalyst was synthesized for the photodegradation of tetracycline hydrochloride (TCH) in the presence of...
In this work, a visible light-driven La/TiO@g-CN photocatalyst was synthesized for the photodegradation of tetracycline hydrochloride (TCH) in the presence of peroxydisulfate (PDS) in an internal loop-lift reactor. The surface morphology and structure of La/TiO@g-CN have been characterized by XRD, SEM-EDS, FTIR, XPS, and UV/vis DRS. La/TiO@g-CN displays outstanding photocatalytic performance and reusability. After four reuse cycles of the vis/La/TiO@g-CN/PDS system, the TCH degradation rate and efficiency still reached 0.083 min and 97.68%, respectively. Reactive species in this system included free radicals SO˙, ˙OH, and ˙O , as well as non-radicals e, and h, as established from the results of chemical quenching experiments. Moreover, a mechanism of action of the vis/La/TiO@g-CN/PDS system for TCH degradation was proposed. The acute toxicity of the reaction solution towards T3 spp. in the vis/La/TiO@g-CN/PDS process increased during the first 60 min and then decreased, illustrating that vis/La/TiO@g-CN/PDS provided an effective and safe method for the removal of TCH.
PubMed: 36926009
DOI: 10.1039/d3ra00729d -
Microbiology Spectrum Mar 2023Emerging evidence confirms using probiotics in promoting growth and immunity of farmed fish. However, the molecular mechanisms underlying the host-microbiome...
Emerging evidence confirms using probiotics in promoting growth and immunity of farmed fish. However, the molecular mechanisms underlying the host-microbiome interactions mediated by probiotics are not fully understood. In this study, we used rainbow trout (Oncorhynchus mykiss) as a model to investigate the internal mechanisms of host-microbiome interactions influenced by two probiotic bacteria, Bacillus velezensis and Lactobacillus sakei. We carried out experiments, including intestinal histology, serum physiology, and transcriptome and combined intestinal microbiome and metabolite profiling. Our results showed that both probiotics had a positive effect on growth, immunity, serum enzyme activity, the gut microbiome, and resistance to Aeromonas salmonicida in rainbow trout. Moreover, the intestinal microbial structure was reshaped with increased relative abundance of potential beneficial bacteria, such as , , , Bacillus coagulans, , , and in the group and and Eubacterium hallii in the group. Metabolomic profiling and transcriptome analysis revealed upregulated metabolites as biomarkers, i.e., sucrose and l-malic acid in the group, and -acetyl-l-phenylalanine, -acetylneuraminic acid, and hydroxyproline in the group. Additionally, a multiomics combined analysis illustrated significant positive correlations between the relative abundance of microflora, metabolites, and gene expression associated with immunity and growth. This study highlights the significant role of probiotics as effectors of intestinal microbial activity and shows that different probiotics can have a species-specific effect on the physiological regulation of the host. These findings contribute to a better understanding of the complex host-microbiome interactions in rainbow trout and may have implications for the use of probiotics in aquaculture. Probiotics are kinds of beneficial live microbes that impart beneficial effects on the host. Recent studies have proven that when given supplementation with probiotics, farmed fish showed improved disease prevention and growth promotion. However, the underlying metabolic functions regarding their involvement in regulating growth phenotypes, nutrient utilization, and immune response are not yet well understood in the aquaculture field. Given the active interactions between the gut microbiota and fish immune and growth performance, we conducted the supplementation experiments with the probiotics Bacillus velezensis and Lactobacillus sakei. The results showed that probiotics mediated intestinal microbiome- and microbiota-derived metabolites regulating the growth and immunity of fish, and different probiotics participated in the species-specific physiological regulation of the host. This study contributed to a better understanding of the functional interactions associated with host health and gut microbiota species.
PubMed: 36916965
DOI: 10.1128/spectrum.03980-22 -
Detection, Identification, and Inactivation of Histamine-forming Bacteria in Seafood: A Mini-review.Journal of Food Protection Mar 2023Seafood is one of the essential sources of nutrients for the human diet. However, they can be subject to contamination and can cause foodborne illnesses, including... (Review)
Review
Seafood is one of the essential sources of nutrients for the human diet. However, they can be subject to contamination and can cause foodborne illnesses, including scombroid fish poisoning caused by histamine. Many microorganisms can produce enzymes that eventually decompose endogenous histidine to histamine in postmortem fish muscles and tissues. One of these is histamine-forming bacteria (HFB), primarily found in the gills, gut, and skin of fishes. Previous studies linked a plethora of Gram-negative HFB including Morganella spp. and Photobacterium spp. to scombroid fish poisoning from many types of seafood, especially the Scombridae family. These bacteria possess the hdc gene to produce histidine decarboxylase enzyme. It was reported that Gram-negative HFB produced 6345 ppm in tuna and 1223 ppm in Spanish mackerel. Interestingly, Gram-positive HFB have been isolated in the seafood samples with lower histamine levels. It suggests that Gram-negative HFB are the major contributor to the accumulation of histamine in seafood. Several analytical methods are available to detect and identify HFB and their histamine metabolites from seafood substrates. Rapid test kits can be used in food production settings for early detection of histamine to avoid food intoxication. Furthermore, high hydrostatic pressure and irradiation treatment could prevent the proliferation of HFB and inactivate the existing histidine decarboxylase (HDC) activity. As demonstrated in different seafood model systems, the HDC activity was deactivated at a maximum high hydrostatic pressure level of 400 MPa. The complete inactivation of HFB was achieved by gamma irradiation at a dose of 4.0 kGy. Other postharvest treatments, like enzymatic degradation and electrolyzed oxidizing water, were studied as sustainable methods for bacterial growth prevention and enzyme inactivation. However, other HFB react differently to these treatment conditions, and further studies are recommended.
Topics: Animals; Humans; Histamine; Histidine Decarboxylase; Bacteria; Seafood; Tuna; Gram-Negative Bacteria; Fishes; Foodborne Diseases
PubMed: 36916556
DOI: 10.1016/j.jfp.2023.100049 -
Nature Communications Feb 2023In bacteria and archaea, tripartite ATP-independent periplasmic (TRAP) transporters uptake essential nutrients. TRAP transporters receive their substrates via a secreted...
In bacteria and archaea, tripartite ATP-independent periplasmic (TRAP) transporters uptake essential nutrients. TRAP transporters receive their substrates via a secreted soluble substrate-binding protein. How a sodium ion-driven secondary active transporter is strictly coupled to a substrate-binding protein is poorly understood. Here we report the cryo-EM structure of the sialic acid TRAP transporter SiaQM from Photobacterium profundum at 2.97 Å resolution. SiaM comprises a "transport" domain and a "scaffold" domain, with the transport domain consisting of helical hairpins as seen in the sodium ion-coupled elevator transporter VcINDY. The SiaQ protein forms intimate contacts with SiaM to extend the size of the scaffold domain, suggesting that TRAP transporters may operate as monomers, rather than the typically observed oligomers for elevator-type transporters. We identify the Na and sialic acid binding sites in SiaM and demonstrate a strict dependence on the substrate-binding protein SiaP for uptake. We report the SiaP crystal structure that, together with docking studies, suggest the molecular basis for how sialic acid is delivered to the SiaQM transporter complex. We thus propose a model for substrate transport by TRAP proteins, which we describe herein as an 'elevator-with-an-operator' mechanism.
Topics: N-Acetylneuraminic Acid; Membrane Transport Proteins; Biological Transport; Archaea; Adenosine Triphosphate
PubMed: 36849793
DOI: 10.1038/s41467-023-36590-1 -
Microorganisms Feb 2023Caribbean sea urchins are marine invertebrates that have experienced a decline over the years. Studies on sea urchins have focused primarily on the microbiome of the...
Caribbean sea urchins are marine invertebrates that have experienced a decline over the years. Studies on sea urchins have focused primarily on the microbiome of the coelomic fluid or the gut microbiota. In this study, the epibiota community associated with four wild Caribbean sea urchin species, , , , and , was characterized for the first time. Using 57 sea urchin animal samples, we evaluated the influence of animal species, trophic niches, and geographical location on the composition of the epibiotic microbiota. We found significant differences in the bacterial biota among species and trophic niches, but not among geographical locations. exhibited the highest alpha diversity with high dominance of Fusobacteria, Planctomycetes, and Cyanobacteria, whereas and were dominated by Firmicutes. inhabiting the seagrass biotope dominated by meadows had mostly In contrast, samples located in the reef (dominated by corals and other reef builders) had a higher abundance of and Our findings confirm that the epibiotic microbiota is species-specific, but also niche-dependent, revealing the trophic networks emerging from the organic matter being recycled in the seagrass and reef niches. As echinoids are important grazers of benthic communities, their microbiota will likely influence ecosystem processes.
PubMed: 36838357
DOI: 10.3390/microorganisms11020391 -
Life (Basel, Switzerland) Feb 2023Marketed fish and shellfish are a source of multidrug-resistant and biofilm-forming foodborne pathogenic microorganisms.
BACKGROUND
Marketed fish and shellfish are a source of multidrug-resistant and biofilm-forming foodborne pathogenic microorganisms.
METHODS
Bacteria isolated from and collected from a local market in Hail region (Saudi Arabia) were isolated on selective and chromogenic media and identified by using 16S RNA sequencing technique. The exoenzyme production and the antibiotic susceptibility patterns of all identified bacteria were also tested. All identified bacteria were tested for their ability to form biofilm by using both qualitative and quantitative assays.
RESULTS
Using 16S RNA sequencing method, eight genera were identified dominated by (42.85%), (23.80%), and (9.52%). The dominant species were (23.8%) and (23.80%). All the identified strains were able to produce several exoenzymes (amylases, gelatinase, haemolysins, lecithinase, DNase, lipase, and caseinase). All tested bacteria were multidrug-resistant with a high value of the multiple antibiotic index (MARI). The antibiotic resistance index (ARI) was about 0.542 for spp. and 0.553 for spp. On Congo red agar, six morphotypes were obtained, and 33.33% were slime-positive bacteria. Almost all tested microorganisms were able to form a biofilm on glass tube. Using the crystal violet technique, the tested bacteria were able to form a biofilm on glass, plastic, and polystyrene abiotic surfaces with different magnitude.
CONCLUSIONS
Our findings suggest that marketed and harbor various bacteria with human interest that are able to produce several related-virulence factors.
PubMed: 36836905
DOI: 10.3390/life13020548 -
International Journal of Molecular... Feb 2023Galectins are proteins that are involved in the innate immune response against pathogenic microorganisms. In the present study, the gene expression pattern of (named as...
Galectins are proteins that are involved in the innate immune response against pathogenic microorganisms. In the present study, the gene expression pattern of (named as ) and its function in mediating the defense response to bacterial attack were investigated. The tertiary structure of Gal-1 protein consists of homodimers and each subunit has one carbohydrate recognition domain. Quantitative RT-PCR analysis indicated that was ubiquitously distributed in all the detected tissues and highly expressed in the swim-bladder of , and its expression could be upregulated by the pathogenic attack in the brain. Expression of Gal-1 protein in HEK 293T cells was distributed in the cytoplasm as well as in the nucleus. The recombinant Gal-1 protein by prokaryotic expression could agglutinate red blood cells from rabbit, , and . The agglutination of red blood cells by the recombinant Gal-1 protein was inhibited by peptidoglycan, lactose, D-galactose, and lipopolysaccharide in certain concentrations. In addition, the recombinant Gal-1 protein agglutinated and killed some gram-negative bacteria including , , , , , and . These results set the stage for further studies of Gal-1 protein in the innate immunity of .
Topics: Animals; Rabbits; Galectin 1; Amino Acid Sequence; Galectins; Perciformes; Immunity, Innate; Cloning, Molecular; Phylogeny; Fish Proteins
PubMed: 36834706
DOI: 10.3390/ijms24043298 -
Frontiers in Microbiology 2023Gut microbiota play important roles in fish health and growth performance and the microbiome in fish has been shown to be a biomarker for stress. In this study, we...
Gut microbiota play important roles in fish health and growth performance and the microbiome in fish has been shown to be a biomarker for stress. In this study, we surveyed the change of Chinook salmon () gut and water microbiota in freshwater recirculating aquaculture systems (RAS) for 7 months and evaluated how gut microbial communities were influenced by fish health and growth performance. The gut microbial diversity significantly increased in parallel with the growth of the fish. The dominant gut microbiota shifted from a predominance of to while constantly dominated the water microbiota. sp. was persistently the major gut microbial community member during the whole experiment and was identified as the core gut microbiota for freshwater farmed Chinook salmon. No significant variation in gut microbial diversity and composition was observed among fish with different growth performance. At the end of the trial, 36 out of 78 fish had fluid in their swim bladders. These fish had gut microbiomes containing elevated proportions of , and . Our study supports the growing body of knowledge about the beneficial microbiota associated with modern salmon aquaculture systems and provides additional information on possible links between dysbiosis and gut microbiota for Chinook salmon.
PubMed: 36825086
DOI: 10.3389/fmicb.2023.1065823 -
Chemical Science Feb 2023All -GalNAc glycans are derived from 8 cores with 2 or 3 monosaccharides linked α- or β-glycosidic bonds. While chemical and chemoenzymatic syntheses of β-linked...
All -GalNAc glycans are derived from 8 cores with 2 or 3 monosaccharides linked α- or β-glycosidic bonds. While chemical and chemoenzymatic syntheses of β-linked cores 1-4 and 6 and derived glycans have been well developed, the preparation of α-linked rare cores 5, 7, and 8 is challenging due to the presence of this 1,2-cis linkage. Meanwhile, the biosynthesis and functional roles of these structures are poorly understood. Herein, we synthesize 3 α-linked rare cores with exclusive α-configuration from a versatile precursor through multifaceted chemical modulations. Efficient regioselective α2-6sialylion of the rare cores was then achieved by α2-6sialyltransferase-catalyzed reactions. These structures, together with β-linked cores 1-4 and 6, and their sialylated forms, were fabricated into a comprehensive -GalNAc core microarray to profile the binding of clinically important GalNAc-specific lectins. It is found that only Tn, (sialyl-)core 5, and core 7 are the binders of WFL, VVL, and SBA, while DBA only recognized (sialyl-)core 5, and Jacalin is the only lectin that binds core 8. In addition, activity assays of human α--acetylgalactosaminide α2-6sialyltransferases (ST6GalNAcTs) towards the cores suggested that ST6GalNAc1 may be involved in the biosynthesis of previously identified sialyl-core 5 and sialyl-core 8 glycans. In conclusion, we provide efficient routes to access α-linked -GalNAc rare cores and derived structures, which are valuable tools for functional glycomics studies of mucin -glycans.
PubMed: 36819867
DOI: 10.1039/d2sc06925c