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1.
Artículo en Inglés | MEDLINE | ID: mdl-38713185

RESUMEN

An aerobic, Gram-stain-negative and short rod-shaped bacterial strain, designated M6-31T, was isolated from rice paddy soil sampled in Miryang, Republic of Korea. Growth was observed at 4-35 °C (optimum, 28 °C), pH 6.0-9.0 (optimum, pH 7.0-8.0) and in the presence of 0-4 % (w/v) NaCl (optimum, 0 % w/v). Phylogenetic analysis based on 16S rRNA gene sequences grouped strain M6-31T with Sphingobacterium bambusae IBFC2009T, Sphingobacterium griseoflavum SCU-B140T and Sphingobacterium solani MLS-26-JM13-11T in the same clade, with the 16S rRNA gene sequence similarities ranging from 95.8 to 96.6 %. A genome-based phylogenetic tree reconstructed by using all publicly available Sphingobacterium genomes placed strain M6-31T with S. bambusae KACC 22910T, 'Sphingobacterium deserti' ACCC 05744T, S. griseoflavum CGMCC 1.12966T and Sphingobacterium paludis CGMCC 1.12801T. Orthologous average nucleotide identity and digital DNA-DNA hybridization values between strain M6-31T and its closely related strains were lower than 74.6 and 22.0 %, respectively. The respiratory quinone was menaquinone-7, and the major polar lipid was phosphatidylethanolamine. The major fatty acids (>10 %) were C15 : 0 iso, C17 : 0 iso 3OH and summed feature 3. The phenotypic, chemotaxonomic and genotypic data obtained in this study showed that strain M6-31T represents a novel species of the genus Sphingobacterium, for which the name Sphingobacterium oryzagri sp. nov. (type strain M6-31T=KACC 22765T=JCM 35893T) is proposed.


Asunto(s)
Técnicas de Tipificación Bacteriana , ADN Bacteriano , Ácidos Grasos , Hibridación de Ácido Nucleico , Oryza , Filogenia , ARN Ribosómico 16S , Análisis de Secuencia de ADN , Microbiología del Suelo , Sphingobacterium , Vitamina K 2 , Vitamina K 2/análogos & derivados , Oryza/microbiología , ARN Ribosómico 16S/genética , Ácidos Grasos/química , Sphingobacterium/genética , Sphingobacterium/aislamiento & purificación , Sphingobacterium/clasificación , ADN Bacteriano/genética , República de Corea , Vitamina K 2/análisis , Composición de Base , Fosfatidiletanolaminas
2.
Artículo en Inglés | MEDLINE | ID: mdl-38578275

RESUMEN

As required by Rule 54 of the International Code of Nomenclature of Prokaryotes, the authors propose the replacement specific epithet 'allocomposti' for the illegitimate prokaryotic name Sphingobacterium composti Yoo et al. 2007, the replacement subspecific epithet 'bovistauri' for Mycobacterium chelonae subsp. bovis Kim et al. 2017 and the replacement subspecific epithet 'allosunkii' for Lactobacillus delbrueckii subsp. sunkii Kudo et al. 2012. Meanwhile, new combinations Christiangramia oceanisediminis and Christiangramia crocea are also proposed as replacements for the illegitimate prokaryotic names Gramella oceanisediminis Yang et al. 2023 and Gramella crocea Zhang et al. 2023, respectively.


Asunto(s)
Lactobacillus delbrueckii , Lactobacillus , Mycobacteriaceae , Mycobacterium chelonae , Sphingobacterium , Análisis de Secuencia de ADN , ADN Bacteriano/genética , Filogenia , Técnicas de Tipificación Bacteriana , ARN Ribosómico 16S/genética , Composición de Base , Ácidos Grasos/química
3.
Chemosphere ; 355: 141806, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38548087

RESUMEN

Environmental challenges arising from organic pollutants pose a significant problem for modern societies. Efficient microbial resources for the degradation of these pollutants are highly valuable. In this study, the bacterial community structure of sludge samples from Taozi Lake (polluted by urban sewage) was studied using 16S rRNA sequencing. The bacterial phyla Proteobacteria, Bacteroidetes, and Chloroflexi, which are potentially important in organic matter degradation by previous studies, were identified as the predominant phyla in our samples, with relative abundances of 48.5%, 8.3%, and 6.6%, respectively. Additionally, the FAPROTAX and co-occurrence network analysis suggested that the core microbial populations in the samples may be closely associated with organic matter metabolism. Subsequently, sludge samples from Taozi Lake were subjected to enrichment cultivation to isolate organic pollutant-degrading microorganisms. The strain Sphingobacterium sp. GEMB-CSS-01, tolerant to sulfanilamide, was successfully isolated. Subsequent investigations demonstrated that Sphingobacterium sp. GEMB-CSS-01 efficiently degraded the endocrine-disrupting compound 17ß-Estradiol (E2). It achieved degradation efficiencies of 80.0% and 53.5% for E2 concentrations of 10 mg/L and 20 mg/L, respectively, within 10 days. Notably, despite a reduction in degradation efficiency, Sphingobacterium sp. GEMB-CSS-01 retained its ability to degrade E2 even in the presence of sulfanilamide concentrations ranging from 50 to 200 mg/L. The findings of this research identify potential microbial resources for environmental bioremediation, and concurrently provide valuable information about the microbial community structure and patterns within Taozi Lake.


Asunto(s)
Contaminantes Ambientales , Sphingobacterium , Aguas del Alcantarillado/microbiología , Sphingobacterium/genética , Sphingobacterium/metabolismo , Lagos/microbiología , ARN Ribosómico 16S/genética , ARN Ribosómico 16S/metabolismo , Estradiol/metabolismo , Biodegradación Ambiental , Contaminantes Ambientales/metabolismo , Sulfanilamidas
4.
J Hazard Mater ; 468: 133485, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38377898

RESUMEN

Biodegradation is an efficient and cost-effective approach to remove residual penicillin G sodium (PGNa) from the environment. In this study, the effective PGNa-degrading strain SQW1 (Sphingobacterium sp.) was screened from contaminated soil using enrichment technique. The effects of critical operational parameters on PGNa degradation by strain SQW1 were systematically investigated, and these parameters were optimized by response surface methodology to maximize PGNa degradation. Comparative experiments found the extracellular enzyme to completely degrade PGNa within 60 min. Combined with whole genome sequencing of strain SQW1 and LC-MS analysis of degradation products, penicillin acylase and ß-lactamase were identified as critical enzymes for PGNa biodegradation. Moreover, three degradation pathways were postulated, including ß-lactam hydrolysis, penicillin acylase hydrolysis, decarboxylation, desulfurization, demethylation, oxidative dehydrogenation, hydroxyl reduction, and demethylation reactions. The toxicity of PGNa biodegradation intermediates was assessed using paper diffusion method, ECOSAR, and TEST software, which showed that the biodegradation products had low toxicity. This study is the first to describe PGNa-degrading bacteria and detailed degradation mechanisms, which will provide new insights into the PGNa biodegradation.


Asunto(s)
Penicilina Amidasa , Sphingobacterium , Sphingobacterium/genética , Sphingobacterium/metabolismo , Penicilina Amidasa/metabolismo , Penicilina G , Biodegradación Ambiental
5.
J Biol Chem ; 300(3): 105728, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38325740

RESUMEN

Serine palmitoyltransferase (SPT) catalyzes the pyridoxal-5'-phosphate (PLP)-dependent decarboxylative condensation of l-serine and palmitoyl-CoA to form 3-ketodihydrosphingosine (KDS). Although SPT was shown to synthesize corresponding products from amino acids other than l-serine, it is still arguable whether SPT catalyzes the reaction with d-serine, which is a question of biological importance. Using high substrate and enzyme concentrations, KDS was detected after the incubation of SPT from Sphingobacterium multivorum with d-serine and palmitoyl-CoA. Furthermore, the KDS comprised equal amounts of 2S and 2R isomers. 1H-NMR study showed a slow hydrogen-deuterium exchange at Cα of serine mediated by SPT. We further confirmed that SPT catalyzed the racemization of serine. The rate of the KDS formation from d-serine was comparable to those for the α-hydrogen exchange and the racemization reaction. The structure of the d-serine-soaked crystal (1.65 Å resolution) showed a distinct electron density of the PLP-l-serine aldimine, interpreted as the racemized product trapped in the active site. The structure of the α-methyl-d-serine-soaked crystal (1.70 Å resolution) showed the PLP-α-methyl-d-serine aldimine, mimicking the d-serine-SPT complex prior to racemization. Based on these enzymological and structural analyses, the synthesis of KDS from d-serine was explained as the result of the slow racemization to l-serine, followed by the reaction with palmitoyl-CoA, and SPT would not catalyze the direct condensation between d-serine and palmitoyl-CoA. It was also shown that the S. multivorum SPT catalyzed the racemization of the product KDS, which would explain the presence of (2R)-KDS in the reaction products.


Asunto(s)
Serina C-Palmitoiltransferasa , Serina , Sphingobacterium , Dominio Catalítico , Cristalización , Medición de Intercambio de Deuterio , Electrones , Hidrógeno/metabolismo , Palmitoil Coenzima A/metabolismo , Serina/análogos & derivados , Serina/metabolismo , Serina C-Palmitoiltransferasa/química , Serina C-Palmitoiltransferasa/metabolismo , Sphingobacterium/enzimología , Sphingobacterium/metabolismo , Esfingosina/análogos & derivados , Esfingosina/biosíntesis , Esfingosina/metabolismo , Estereoisomerismo , Especificidad por Sustrato
6.
Environ Sci Pollut Res Int ; 31(3): 3495-3511, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38085488

RESUMEN

With the accelerated modernization of agriculture and industry, sulfides have been released into the environment as a by-products of various production processes. Elevated levels of sulfide pose a threat to organisms' health and disrupt ecosystem equilibrium. This study successfully isolated two highly efficient sulfur-oxidizing strains, namely Pseudomonas aeruginosa GHWS3 and Sphingobacterium sp. GHWS5. Neither strain exhibited hemolytic activity or pathogenicity. Additionally, GHWS3 inhibited the common aquaculture pathogen Vibrio anguillarum, while GHWS5 exhibited inhibitory effects against Vibrio harveyi. GHWS3 and GHWS5 demonstrated effective removal of sulfide under the following conditions: temperature range of 20-40 °C, pH level of 4.5-8.5, salinity range of 0-50‰, C/N ratio of 5-15, and sulfide concentration of 20-200 mg/L. By amplifying the key functional genes of the sulfur-oxidizing Sox and rDsr systems in both GHWS3 and GHWS5 strains, potential desulfurization pathways were analyzed. Furthermore, both strains displayed high efficiency in removing sulfides from actual aquaculture pond substrate mixtures. The findings of this study provide two promising candidate strains for sulfides removal from farm tailwater, industrial wastewater, and domestic wastewater.


Asunto(s)
Sphingobacterium , Aguas Residuales , Sphingobacterium/metabolismo , Pseudomonas/metabolismo , Ecosistema , Reactores Biológicos/microbiología , Oxidación-Reducción , Azufre/metabolismo , Sulfuros/metabolismo
7.
Water Res ; 243: 120397, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37499542

RESUMEN

As an emerging pollutant, the antibiotic tetracycline (TC) has been consistently detected in wastewater and activated sludge. Biodegradation represents a potentially crucial pathway to dissipate TC contamination. However, few efficient TC-degrading bacteria have been isolated and a comprehensive understanding of the molecular mechanisms underlying TC degradation is still lacking. In this study, a novel TC-degrading bacterium, designated as Sphingobacterium sp. WM1, was successfully isolated from activated sludge. Strain WM1 exhibited a remarkable performance in degrading 50 mg/L TC within 1 day under co-metabolic conditions. Genomic analysis of the strain WM1 unveiled the presence of three functional tetX genes. Unraveling the complex molecular mechanisms, transcriptome analysis highlighted the role of upregulated transmembrane transport and accelerated electron transport in facilitating TC degradation. Proteomics confirmed the up-regulation of proteins involved in cellular biosynthesis/metabolism and ribosomal processes. Crucially, the tetX gene-encoding protein showed a significant upregulation, indicating its role in TC degradation. Heterologous expression of the tetX gene resulted in TC dissipation from an initial 51.9 mg/L to 4.2 mg/L within 24 h. The degradation pathway encompassed TC hydroxylation, transforming into TP461 and subsequent metabolites, which effectively depleted TC's inhibitory activity. Notably, the tetX genes in strain WM1 showed limited potential for horizontal gene transfer. Collectively, strain WM1's potent TC degradation capacity signals a promise for enhancing TC clean-up strategies.


Asunto(s)
Aguas del Alcantarillado , Sphingobacterium , Aguas del Alcantarillado/microbiología , Sphingobacterium/metabolismo , Multiómica , Antibacterianos/metabolismo , Tetraciclina/metabolismo , Bacterias/metabolismo , Biodegradación Ambiental
8.
Saudi Med J ; 44(6): 544-559, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37343981

RESUMEN

OBJECTIVES: To develop a candidate vaccine aginst the Sphingobacterium spiritivorum. METHODS: Since there is currently no vaccine against this pathogen, we employed in-silico methods to extensively explore the outer membrane toxin-producing proteins found specifically in S. spiritivorum to forecast a multi-epitope chimeric vaccine design. This computational study was conducted in Saudi Arabia in 2022 (study design: computational; ethical approval not applicable). RESULTS: TThe vaccine peptide comprises multiple linear and conformational B-cell epitopes, which have the potential to elicit humoral immunity. Projected B-cell- derived T-cell epitopes for outer membrane proteins are present in the produced protein. The docking and molecular dynamic simulation results indicating that the chimeric vaccine had adequate binding stability with TLR-4. Following the immunological simulation, significant levels of immune cell expression were observed as immunoglobulin (Ig) M and IgG, IgM, IgM1, and IgM2, and independently IgG1 and IgG2. CONCLUSION: The developed vaccine candidate is suitable for further testing and can assist experimental vaccinologists in developing an effective vaccine against S. spiritivorum.


Asunto(s)
Sphingobacterium , Vacunología , Humanos , Vacunología/métodos , Epítopos de Linfocito B/química , Arabia Saudita
9.
J Biol Chem ; 299(5): 104684, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37030501

RESUMEN

Serine palmitoyltransferase (SPT) is a key enzyme of sphingolipid biosynthesis, which catalyzes the pyridoxal-5'-phosphate-dependent decarboxylative condensation reaction of l-serine (l-Ser) and palmitoyl-CoA (PalCoA) to form 3-ketodihydrosphingosine called long chain base (LCB). SPT is also able to metabolize l-alanine (l-Ala) and glycine (Gly), albeit with much lower efficiency. Human SPT is a membrane-bound large protein complex containing SPTLC1/SPTLC2 heterodimer as the core subunits, and it is known that mutations of the SPTLC1/SPTLC2 genes increase the formation of deoxy-type of LCBs derived from l-Ala and Gly to cause some neurodegenerative diseases. In order to study the substrate recognition of SPT, we examined the reactivity of Sphingobacterium multivorum SPT on various amino acids in the presence of PalCoA. The S. multivorum SPT could convert not only l-Ala and Gly but also l-homoserine, in addition to l-Ser, into the corresponding LCBs. Furthermore, we obtained high-quality crystals of the ligand-free form and the binary complexes with a series of amino acids, including a nonproductive amino acid, l-threonine, and determined the structures at 1.40 to 1.55 Å resolutions. The S. multivorum SPT accommodated various amino acid substrates through subtle rearrangements of the active-site amino acid residues and water molecules. It was also suggested that non-active-site residues mutated in the human SPT genes might indirectly influence the substrate specificity by affecting the hydrogen-bonding networks involving the bound substrate, water molecules, and amino acid residues in the active site of this enzyme. Collectively, our results highlight SPT structural features affecting substrate specificity for this stage of sphingolipid biosynthesis.


Asunto(s)
Serina C-Palmitoiltransferasa , Sphingobacterium , Humanos , Palmitoil Coenzima A/química , Palmitoil Coenzima A/metabolismo , Serina/química , Serina C-Palmitoiltransferasa/genética , Serina C-Palmitoiltransferasa/metabolismo , Sphingobacterium/enzimología , Esfingolípidos/metabolismo , Especificidad por Sustrato
11.
Gene ; 855: 147118, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36521669

RESUMEN

Sphingobacterium is a class of Gram-negative, non-fermentative bacilli that have received widespread attention due to their broad ecological distribution and oil degradation ability, but are rarely involved in infections. In this manuscript, a novel Sphingobacterium strain isolated from wildfire-infected tobacco leaves was named Sphingobacterium sp. CZ-2. NGS and TGS sequencing results showed a whole genome of 3.92 Mb with 40.68 mol% GC content and containing 3,462 protein-coding genes, 9 rRNA-coding genes and 50 tRNA-coding genes. Phylogenetic analysis, ANI and dDDH calculations all supported that Sphingobacterium sp. CZ-2 represented a novel species of the genus Sphingobacterium. Analysis of the specific genes of Sphingobacterium sp. CZ-2 by comparative genomics revealed that metal transport proteins encoded by the troD and cusA genes could maintain the balance of heavy metal ion concentrations in the internal environment of bacteria and avoid heavy metal toxicity while meeting the needs of growth and reproduction, and transport proteins encoded by the malG gene could keep nutrients required for the survival of bacteria. Synteny and genome evolutionary analyses of Sphingobacterium strains implicated that the gene family contraction as a major process in genome evolution, with insertional sequences leading to mutations, deletions and reversals of genes that help bacteria to withstand complex environmental changes. Complete genome sequencing and systematic comparative genomic analysis will contribute new insights into the adaptive evolution of this novel species and the genus Sphingobacterium.


Asunto(s)
Ácidos Grasos , Sphingobacterium , Filogenia , Sphingobacterium/genética , Análisis de Secuencia de ADN , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética , ARN Ribosómico 16S/genética , Genómica
12.
Indian J Med Microbiol ; 43: 36-38, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36328828

RESUMEN

Sphingobacterium species are ubiquitous and are abundant in nature and rarely involved in causing human infections. A 62-year-old man presented with recurrent episodes of high fever up to 40 â€‹°C accompanied by rigors, sweating, and malaise for the past 4 weeks. After a thorough workup, only elevated C-reactive protein with a leucocytosis was evident. Blood culture showed growth of Gram-negative bacilli which was identified as spingobacterium spiritivorum. Although S. spiritivorum is rare, with limited cases reported in the literature, it must be considered as a causative organism in patients with persistent fevers with sepsis.


Asunto(s)
Fiebre de Origen Desconocido , Sepsis , Sphingobacterium , Masculino , Humanos , Persona de Mediana Edad , Sepsis/diagnóstico , Sepsis/complicaciones , Fiebre de Origen Desconocido/diagnóstico , Fiebre de Origen Desconocido/etiología
13.
Food Microbiol ; 109: 104126, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36309436

RESUMEN

Foodborne norovirus (NoV) outbreaks linked to leafy greens are common due to a lack of efficient strategies to prevent NoV spread from contaminated surfaces. We previously found that Sphingobacterium sp. SC015 in lettuce phyllosphere expresses histo-blood group antigen (HBGA)-like substances in soluble extracellular polymeric substances (SEPS) that contribute to NoV adherence on lettuce. Here, we extracted SEPS from bacterium SC015 (SEPS-SC015), analyzed their chemical composition, and examined their roles in the survival and protection of NoV and surrogates [murine norovirus (MNV-1) and Tulane virus (TuV)] on lettuce. Presence of SEPS-SC015 significantly increased survival and persistence of human NoV (HuNoV), MNV-1, and TuV at days 7 and 14, compared with virus alone. HuNoV, TuV, and MNV-1 seeded with SEPS-SC015 were more resistant to heat (70 °C, 2 min) than these viruses alone. SEPS-SC015 also increased viral resistance to sodium hypochlorite inactivation by treatment with 30 and 300 ppm bleach at 26 °C for 10 min. However, SEPS-SC015 was not effective at protecting these viruses under UV inactivation. Binding of TuV to SC015 bacteria and SEPS-SC015, visualized using transmission electron microscopy, suggests that protection might be related to direct interaction between SEPS-SC015 and viral particles. This study provides important insights that will help inform strategies to improve food safety.


Asunto(s)
Antígenos de Grupos Sanguíneos , Norovirus , Sphingobacterium , Humanos , Ratones , Animales , Lactuca , Matriz Extracelular de Sustancias Poliméricas , Bacterias
14.
Glycobiology ; 33(1): 47-56, 2023 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-36036828

RESUMEN

Sialic acid (Sia) is a group of acidic sugars with a 9-carbon backbone, and classified into 3 species based on the substituent group at C5 position: N-acetylneuraminic acid (Neu5Ac), N-glycolylneuraminic acid (Neu5Gc), and deaminoneuraminic acid (Kdn). In Escherichia coli, the sialate aldolase or N-acetylneuraminate aldolase (NanA) is known to catabolize these Sia species into pyruvate and the corresponding 6-carbon mannose derivatives. However, in bacteria, very little is known about the catabolism of Kdn, compared with Neu5Ac. In this study, we found a novel Kdn-specific aldolase (Kdn-aldolase), which can exclusively degrade Kdn, but not Neu5Ac or Neu5Gc, from Sphingobacterium sp., which was previously isolated from a Kdn-assimilating bacterium. Kdn-aldolase had the optimal pH and temperature at 7.0-8.0 and 50 °C, respectively. It also had the synthetic activity of Kdn from pyruvate and mannose. Site-specific mutagenesis revealed that N50 residue was important for the Kdn-specific reaction. Existence of the Kdn-aldolase suggests that Kdn-specific metabolism may play a specialized role in some bacteria.


Asunto(s)
Sphingobacterium , Sphingobacterium/genética , Sphingobacterium/metabolismo , Azúcares Ácidos/metabolismo , Fructosa-Bifosfato Aldolasa , Manosa , Ácido N-Acetilneuramínico/metabolismo , Bacterias/metabolismo , Aldehído-Liasas/genética , Piruvatos
15.
Microbiol Spectr ; 10(6): e0142221, 2022 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-36314920

RESUMEN

Sphingobacterium sp. is a yellowish Gram-negative bacterium that is usually characterized by high concentrations of sphingophospholipids as lipid components. As microbial enzymes have been in high demand in industrial fields in the past few decades, this study hopes to provide significant information on lipase activities of Sphingobacterium sp., since limited studies have been conducted on the Sphingobacterium sp. lipase. A microbe from one collected Artic soil sample, ARC4, was identified as psychrotolerant Sphingobacterium sp., and it could grow in temperatures ranging from 0°C to 24°C. The expression of Sphingobacterium sp. lipase was successfully performed through an efficient approach of utilizing mutated group 3 late embryogenesis abundant (G3LEA) proteins developed from Polypedilum vanderplanki. Purified enzyme was characterized using a few parameters, such as temperature, pH, metal ion cofactors, organic solvents, and detergents. The expressed enzyme is reported to be cold adapted and has the capability to work efficiently under neutral pH (pH 5.0 to 7.0), cofactors like Na+ ion, and the water-like solvent methanol. Addition of nonionic detergents greatly enhanced the activity of purified enzyme. IMPORTANCE The mechanism of action of LEA proteins has remained unknown to many; in this study we reveal their presence and improved protein expression due to the molecular shielding effect reported by others. This paper should be regarded as a useful example of using such proteins to influence an existing expression system to produce difficult-to-express proteins.


Asunto(s)
Lipasa , Sphingobacterium , Lipasa/genética , Lipasa/química , Lipasa/metabolismo , Sphingobacterium/metabolismo , Detergentes/metabolismo , Temperatura , Solventes/metabolismo , Péptidos/metabolismo , Concentración de Iones de Hidrógeno , Filogenia
16.
Nature ; 608(7924): 803-807, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35859168

RESUMEN

Stimulator of interferon genes (STING) is an antiviral signalling protein that is broadly conserved in both innate immunity in animals and phage defence in prokaryotes1-4. Activation of STING requires its assembly into an oligomeric filament structure through binding of a cyclic dinucleotide4-13, but the molecular basis of STING filament assembly and extension remains unknown. Here we use cryogenic electron microscopy to determine the structure of the active Toll/interleukin-1 receptor (TIR)-STING filament complex from a Sphingobacterium faecium cyclic-oligonucleotide-based antiphage signalling system (CBASS) defence operon. Bacterial TIR-STING filament formation is driven by STING interfaces that become exposed on high-affinity recognition of the cognate cyclic dinucleotide signal c-di-GMP. Repeating dimeric STING units stack laterally head-to-head through surface interfaces, which are also essential for human STING tetramer formation and downstream immune signalling in mammals5. The active bacterial TIR-STING structure reveals further cross-filament contacts that brace the assembly and coordinate packing of the associated TIR NADase effector domains at the base of the filament to drive NAD+ hydrolysis. STING interface and cross-filament contacts are essential for cell growth arrest in vivo and reveal a stepwise mechanism of activation whereby STING filament assembly is required for subsequent effector activation. Our results define the structural basis of STING filament formation in prokaryotic antiviral signalling.


Asunto(s)
Proteínas Bacterianas , Microscopía por Crioelectrón , Proteínas de la Membrana , Receptores de Interleucina-1 , Sphingobacterium , Receptores Toll-Like , Animales , Antivirales/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/inmunología , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/ultraestructura , Bacteriófagos/inmunología , Fosfatos de Dinucleósidos/metabolismo , Humanos , Inmunidad Innata , Proteínas de la Membrana/química , Proteínas de la Membrana/inmunología , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/ultraestructura , Operón/genética , Receptores de Interleucina-1/química , Receptores de Interleucina-1/inmunología , Receptores de Interleucina-1/metabolismo , Receptores de Interleucina-1/ultraestructura , Sphingobacterium/química , Sphingobacterium/genética , Sphingobacterium/ultraestructura , Sphingobacterium/virología , Receptores Toll-Like/química , Receptores Toll-Like/inmunología , Receptores Toll-Like/metabolismo , Receptores Toll-Like/ultraestructura
17.
J Infect Chemother ; 28(10): 1419-1423, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35718261

RESUMEN

INTRODUCTION: Sphingobacterium is an aerobic, glucose non-fermenting, Gram-negative rod bacterium that has been isolated from soil, plants, food, and water sources, including in hospitals. Reports of systemic infections caused by Sphingobacterium multivorum (S. multivorum) are rare, and their clinical and microbiological characteristics remain unclear. Moreover, conventional microbiological methods have limited ability to identify S. multivorum. We report the first case of obstructive cholangitis with bacteremia caused by S. multivorum in a patient with gastric cancer. CASE REPORT: A 68-year-old woman with advanced gastric cancer, hypertension, and hyperlipidemia was admitted with obstructive jaundice, and subsequently developed obstructive cholangitis during the hospital stay. S. multivorum were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and 16S ribosomal RNA sequencing of the patient's blood samples. Based on the antibiotic susceptibility results of the isolates, cefepime was administered intravenously for 14 days, with good therapeutic outcomes. CONCLUSIONS: S. multivorum infection is rare, and its microbiology and pathogenicity in humans is mostly unknown. Therefore, multiple diagnostic approaches should be used to identify S. multivorum, and antimicrobial therapy should be selected based on the in vitro susceptibility. This report provides clinicians with novel information on the clinical manifestations and diagnostic methods for an accurate diagnosis of S. multivorum.


Asunto(s)
Bacteriemia , Colangitis , Sphingobacterium , Neoplasias Gástricas , Acinetobacter , Anciano , Bacteriemia/diagnóstico , Bacteriemia/tratamiento farmacológico , Colangitis/complicaciones , Colangitis/tratamiento farmacológico , Femenino , Humanos , ARN Ribosómico 16S/genética , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Sphingobacterium/genética , Neoplasias Gástricas/complicaciones
18.
Environ Pollut ; 305: 119299, 2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35430309

RESUMEN

Contamination by tetracycline residues has adverse influences on the environment and is considered a pressing issue. Biodegradation is regarded as a promising way to treat tetracycline residues in the environment. Here, strain Sphingobacterium mizutaii S121, which could degrade 20 mg/L tetracycline completely within 5 days, was isolated from contaminated soil. The characteristics of tetracycline degradation by strain S121 were investigated under various culture conditions. Response surface methodology was used to predict the maximum tetracycline degradation ratio, which can be obtained under the following conditions: 31.36 °C, pH of 7.15, and inoculum volume of 5.5% (v/v). Furthermore, extracellular tetracycline biodegradation products and intracellular metabolic pathways of S121 were detected by ultraperformance liquid chromatography-quadrupole-time-of-flight-mass spectrometry (UPLC-Q-TOF-MS) and UHPLC-quadrupole electrospray (QE)-MS, respectively. The results identified eight possible degradation products, and three putative degradation pathways were proposed. In addition, exposure to tetracycline produced significant influences on metabolic pathways such as pyrimidine, purine, taurine and hypotaurine metabolism and lysine degradation. Consequently, the intracellular metabolic pathway response of S121 in the presence of tetracycline was proposed. These findings are presented for the first time, which will facilitate a comprehensive understanding of the mechanism of tetracycline degradation. Moreover, strain S121 can be a promising bacterium for tetracycline bioremediation.


Asunto(s)
Sphingobacterium , Tetraciclina , Antibacterianos/metabolismo , Biodegradación Ambiental , Metabolómica , Sphingobacterium/metabolismo , Tetraciclina/análisis
19.
World J Microbiol Biotechnol ; 38(5): 78, 2022 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-35325312

RESUMEN

A lignocellulolytic microbial consortium holds promise for the in situ biodegradation of crop straw and the comprehensive and effective utilization of agricultural waste. In this study, we applied metagenomics technology to comprehensively explore the metabolic functional potential and taxonomic diversity of the microbial consortia CS (cultured on corn stover) and FP (cultured on filter paper). Analyses of the data on metagenomics taxonomic affiliations revealed considerable differences in the taxonomic composition and carbohydrate-active enzymes profile of the microbial consortia CS and FP. Pseudomonas, Dysgonomonas and Sphingobacterium in CS and Cellvibrio and Pseudomonas in FP had a much wider distribution of lignocellulose degradative ability. The genes for more lignocellulose degradative enzymes were detected when the relatively simple substrate filter paper was used as the carbon source. Clusters of Orthologous Groups (COG) and Kyoto Encyclopedia of Genes and Genomes (KEGG) annotation analyses revealed considerable levels of similarity, and carbohydrate metabolic and amino acid metabolic pathways were the most enriched in CS and FP, respectively. The mechanism used by the two microbial consortia to degrade lignocellulose was similar, but the annotation of quantity of genes indicated that they are diverse and vary greatly. These data underlie the interactions between microorganisms and the synergism of enzymes during the degradative process of lignocellulose under different substrates and suggest the development of potential microbial resources.


Asunto(s)
Consorcios Microbianos , Sphingobacterium , Bacterias/metabolismo , Carbono/metabolismo , Metagenómica , Consorcios Microbianos/genética
20.
Curr Microbiol ; 79(3): 92, 2022 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-35129696

RESUMEN

A novel bacterium designated WQ 366 T was isolated from the faeces of Bos taurus, foraging on the slopes of the Baima Snow Mountain in Yunnan, China. The isolate grew optimally at 30 â„ƒ and pH 7.0-8.0 without NaCl. The cells were Gram-stain-negative, aerobic, rod-shaped, non-gliding, catalase-positive, and produced yellow color colonies on Columbia Agar. A polyphasic study was applied to clarify its taxonomic position through 16S rRNA gene and genome sequence analysis, and other extensive biological typing. Phylogenetic analysis revealed that the isolate was affiliated to the genus Sphingobacterium and its 16S rRNA gene sequence was closely related to Sphingobacterium bovisgrunnientis YK2 T (97.3%), Sphingobacterium composti T5-12 T (96.4%), and Sphingobacterium cavernae 5.0403-2 T (96.4%). The calculated whole genome average nucleotide identity (ANI) and the digital DNA-DNA hybridization values between strain WQ 366 T and the three related strains were 78.3, 78.6, 73.9 and 21.2, 21.2, 21.0%, respectively. The predominant fatty acids (>10%) were iso-C15:0, iso-C17:0 3-OH, Summed Feature 3 (C16:1 ω7c and/or C16:1 ω6c), and Summed feature 9 (iso-C17:1 ω9c and 10-methyl C16:0). The main polar lipids were PE, GPL, GL, and PL. MK-7 was the major menaquinone. The genome size and the G + C content of WQ 366 T was 4.1 Mb and 34.6%, respectively. All these results indicated that strain WQ 366 T represents a novel species of the Sphingobacterium genus. Therefore, the name Sphingobacterium bovistauri sp. nov. is proposed, and the type strain is WQ 366 T (= CCTCC AA 2020029 T = KCTC 82395 T).


Asunto(s)
Sphingobacterium , Animales , Técnicas de Tipificación Bacteriana , Bovinos , China , ADN Bacteriano/genética , Ácidos Grasos , Heces , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Sphingobacterium/genética , Vitamina K 2
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