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SLC7A11 plays a pivotal role in tumour development by facilitating cystine import to enhance glutathione synthesis and counteract oxidative stress. Disulphidptosis, an emerging form of cell death observed in cells with high expression of SLC7A11 under glucose deprivation, is regulated through reduction-oxidation reactions and disulphide bond formation. This process leads to contraction and collapse of the F-actin cytoskeleton from the plasma membrane, ultimately resulting in cellular demise. Compared to other forms of cell death, disulphidptosis exhibits distinctive characteristics and regulatory mechanisms. This mechanism provides novel insights and innovative strategies for cancer treatment while also inspiring potential therapeutic approaches for other diseases. Our review focuses on elucidating the molecular mechanism underlying disulphidptosis and its connection with the actin cytoskeleton, identifying alternative metabolic forms of cell death, as well as offering insights into disulphidptosis-based cancer therapy. A comprehensive understanding of disulphidptosis will contribute to our knowledge about fundamental cellular homeostasis and facilitate the development of groundbreaking therapies for disease treatment.
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The understanding of activated sludge microbial status and roles is imperative for improving and enhancing the performance of wastewater treatment plants (WWTPs). In this study, we conducted a deep analysis of activated sludge microbial communities across five compartments (inflow, effluent, and aerobic, anoxic, anaerobic tanks) over temporal scales, employing high-throughput sequencing of 16S rRNA amplicons and metagenome data. Clearly discernible seasonal patterns, exhibiting cyclic variations, were observed in microbial diversity, assembly, co-occurrence network, and metabolic functions. Notably, summer samples exhibited higher α-diversity and were distinctly separated from winter samples. Our analysis revealed that microbial community assembly is influenced by both stochastic processes (66%) and deterministic processes (34%), with winter samples demonstrating more random assembly compared to summer. Co-occurrence patterns were predominantly mutualistic, with over 96% positive correlations, and summer networks were more organized than those in winter. These variations were significantly correlated with temperature, total phosphorus and sludge volume index. However, no significant differences were found among microbial community across five compartments in terms of ß diversity. A core community of keystone taxa was identified, playing key roles in eight nitrogen and eleven phosphorus cycling pathways. Understanding the assembly mechanisms, co-occurrence patterns, and functional roles of microbial communities is essential for the design and optimization of biotechnological treatment processes in WWTPs.
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Intervertebral disc degeneration (IVDD) is a leading cause of degenerative spinal disorders, involving complex biological processes. This study investigates the role of the kallikrein-kinin system (KKS) in IVDD, focusing on the protective effects of bradykinin (BK) on nucleus pulposus cells (NPCs) under oxidative stress. Clinical specimens were collected, and experiments were conducted using human and rat primary NPCs to elucidate BK's impact on tert-butyl hydroperoxide (TBHP)-induced oxidative stress and damage. The results demonstrate that BK significantly inhibits TBHP-induced NPC apoptosis and restores mitochondrial function. Further analysis reveals that this protective effect is mediated through the BK receptor 2 (B2R) and its downstream PI3K/AKT pathway. Additionally, BK/PLGA sustained-release microspheres were developed and validated in a rat model, highlighting their potential therapeutic efficacy for IVDD. Overall, this study sheds light on the crucial role of the KKS in IVDD pathogenesis and suggests targeting the B2R as a promising therapeutic strategy to delay IVDD progression and promote disc regeneration.
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Apoptosis , Bradiquinina , Degeneración del Disco Intervertebral , Núcleo Pulposo , Estrés Oxidativo , terc-Butilhidroperóxido , Animales , Femenino , Humanos , Masculino , Ratas , Apoptosis/efectos de los fármacos , Bradiquinina/farmacología , Células Cultivadas , Modelos Animales de Enfermedad , Degeneración del Disco Intervertebral/tratamiento farmacológico , Degeneración del Disco Intervertebral/patología , Microesferas , Núcleo Pulposo/efectos de los fármacos , Núcleo Pulposo/patología , Núcleo Pulposo/metabolismo , Estrés Oxidativo/efectos de los fármacos , Fosfatidilinositol 3-Quinasas/metabolismo , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas Sprague-Dawley , Receptor de Bradiquinina B2/metabolismo , Transducción de Señal/efectos de los fármacos , terc-Butilhidroperóxido/toxicidadRESUMEN
A yellow pigmented, Gram-stain-positive, motile, facultatively anaerobic and irregular rod-shaped bacteria (strain M0-14T) was isolated from a till sample collected from the foreland of a high Arctic glacier near the settlement of Ny-Ålesund in the Svalbard Archipelago, Norway. Phylogenetic analysis based on 16S rRNA gene sequence comparisons revealed that M0-14T formed a lineage within the family Cellulomonadaceae, suborder Micrococcineae. M0-14T represented a novel member of the genus Pengzhenrongella and had highest 16S rRNA gene sequence similarity to Pengzhenrongella sicca LRZ-2T (97.3â%). Growth occurred at 4-25â°C (optimum 4-18â°C), at pH 6.0-9.0 (optimum pH 7.0), and in the presence of 0-5â% (w/v) NaCl. The predominant menaquinone was MK-9(H4) and the major fatty acids were anteiso-C15â:â0, C16â:â0 and summed feature 3 (comprising C16â:â1ω7c and/or C16â:â1ω6c). The major polar lipids were phosphatidylglycerol, phosphatidylinositol mannosides, phosphatidylinositol, one undefined phospholipid and five undefined phosphoglycolipids. The cell-wall diamino acid was l-ornithine whereas rhamnose and mannose were the cell-wall sugars. Polyphosphate particles were found inside the cells of M0-14T. Polyphosphate kinase and polyphosphate-dependent glucokinase genes were detected during genomic sequencing of M0-14. In addition, the complete pstSCAB gene cluster and phnCDE synthesis genes, which are important for the uptake and transport of phosphorus in cells, were annotated in the genomic data. According to the genomic data, M0-14T has a metabolic pathway related to phosphorus accumulation. The DNA G+C content of the genomic DNA was 70.8â%. On the basis of its phylogenetic relationship, phenotypic properties and chemotaxonomic distinctiveness, strain M0-14T represents a novel species of the genus Pengzhenrongella, for which the name Pengzhenrongella phosphoraccumulans sp. nov. is proposed. The type strain is M0-14T (= CCTCC AB 2012967T = NRRL B-59105T).
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Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano , Ácidos Grasos , Cubierta de Hielo , Filogenia , ARN Ribosómico 16S , Análisis de Secuencia de ADN , Vitamina K 2 , ARN Ribosómico 16S/genética , Regiones Árticas , Ácidos Grasos/química , Vitamina K 2/análogos & derivados , ADN Bacteriano/genética , Cubierta de Hielo/microbiología , Fosfolípidos , SvalbardRESUMEN
Intervertebral disc degeneration (IDD) is a prevalent musculoskeletal degenerative disorder worldwide, and ~40% of chronic low back pain cases are associated with IDD. Although the pathogenesis of IDD remains unclear, the reduction in nucleus pulposus cells (NPCs) and degradation of the extracellular matrix (ECM) are critical factors contributing to IDD. Notochordal cells (NCs), derived from the notochord, which rapidly degrades after birth and is eventually replaced by NPCs, play a crucial role in maintaining ECM homeostasis and preventing NPCs apoptosis. Current treatments for IDD only provide symptomatic relief, while lacking the ability to inhibit or reverse its progression. However, NCs and their secretions possess anti-inflammatory properties and promote NPCs proliferation, leading to ECM formation. Therefore, in recent years, NCs therapy targeting the underlying cause of IDD has emerged as a novel treatment strategy. This article provides a comprehensive review of the latest research progress on NCs for IDD, covering their biological characteristics, specific markers, possible mechanisms involved in IDD and therapeutic effects. It also highlights significant future directions in this field to facilitate further exploration of the pathogenesis of IDD and the development of new therapies based on NCs strategies.
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Degeneración del Disco Intervertebral , Disco Intervertebral , Núcleo Pulposo , Humanos , Degeneración del Disco Intervertebral/metabolismo , Notocorda/metabolismo , Notocorda/patología , Núcleo Pulposo/metabolismo , Proliferación Celular , Apoptosis , Disco Intervertebral/patologíaRESUMEN
The dysregulation of intracellular and extracellular environments as well as the aberrant expression of ion channels on the cell membrane are intricately linked to a diverse array of degenerative disorders, including intervertebral disc degeneration. This condition is a significant contributor to low back pain, which poses a substantial burden on both personal quality of life and societal economics. Changes in the number and function of ion channels can disrupt the water and ion balance both inside and outside cells, thereby impacting the physiological functions of tissues and organs. Therefore, maintaining ion homeostasis and stable expression of ion channels within the cellular microenvironment may prove beneficial in the treatment of disc degeneration. Aquaporin (AQP), calcium ion channels, and acid-sensitive ion channels (ASIC) play crucial roles in regulating water, calcium ions, and hydrogen ions levels. These channels have significant effects on physiological and pathological processes such as cellular aging, inflammatory response, stromal decomposition, endoplasmic reticulum stress, and accumulation of cell metabolites. Additionally, Piezo 1, transient receptor potential vanilloid type 4 (TRPV4), tension response enhancer binding protein (TonEBP), potassium ions, zinc ions, and tungsten all play a role in the process of intervertebral disc degeneration. This review endeavors to elucidate alterations in the microenvironment of the nucleus pulposus during intervertebral disc degeneration (IVDD), with a view to offer novel insights and approaches for exploring therapeutic interventions against disc degeneration.
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Degeneración del Disco Intervertebral , Disco Intervertebral , Núcleo Pulposo , Humanos , Núcleo Pulposo/metabolismo , Degeneración del Disco Intervertebral/metabolismo , Calidad de Vida , Disco Intervertebral/metabolismo , Canales Iónicos/metabolismo , Homeostasis/fisiología , Iones/metabolismo , Agua/metabolismoRESUMEN
The propagation of antibiotic resistance genes (ARGs) in environments has evoked many attentions, however, how to identify their host pathogenic bacteria in situ remains a great challenge. Here we explored the bacterial host distribution and dissemination of a typical ARG, sul1 gene, in agricultural soils through the simultaneous detection of sul1 and its host 16S rRNA gene by emulsion paired isolation and concatenation PCR (epicPCR). Compared to chemical fertilizer, organic fertilizer (chicken manure) led to a higher prevalence of sul1 gene in the soil, and dominant bacterial hosts of sul1 gene were classified into Proteobacteria and Bacteroidetes phyla. Additionally, significant higher diversity of antibiotic resistance bacteria (ARB), higher rate of horizontal gene transfer (HGT), higher rate of mobile genetic elements (MGE) and higher proportion of pathogens were all observed in the treatment of organic fertilizer. This study alerts potential health risks of manure applications in agricultural soils.
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Fertilizantes , Estiércol , Antagonistas de Receptores de Angiotensina , Inhibidores de la Enzima Convertidora de Angiotensina , Antibacterianos/farmacología , Bacterias/genética , Farmacorresistencia Microbiana/genética , Fertilizantes/análisis , Genes Bacterianos , Estiércol/microbiología , ARN Ribosómico 16S/genética , Suelo , Microbiología del SueloRESUMEN
Global warming is likely to affect the underground microbial communities in various ecosystems, but the response of soil microbial communities along a vertical depth profile to global warming has been elusive. Herein, we leveraged a warming field experiment in Qinghai-Tibet Plateau grassland and investigated the community structure of prokaryotes and fungi from the upper (0-15 cm) and lower (15-30 cm) strata under ambient and elevated temperature treatments. Three-years continual warming only significantly shifted the prokaryotic community within the upper strata and there was no significant effect observed for the fungal community. Additionally, under ambient temperature, there were significant differences between the two strata in both the prokaryotic and fungal communities, but under warming, this effect was alleviated. Next, the prokaryotic and fungal community assembly processes were measured by a phylogenetic-bin-based null approach (iCAMP). Though deterministic and stochastic processes dominated the assembly of prokaryotic and fungal communities, respectively, the deterministic processes were strengthened under warming for both communities. Specifically, the increased portion of homogeneous selection, contributing to a homogenous state, led to a smaller difference between prokaryotic communities of the two soil strata under warming. The smaller difference in the stochastic process component, i.e., dispersal limitation, contributed to the similar fungal community structures between the two strata under warming. This study deepens our understanding of warming effects on grassland microbial communities and gives greater insights on the underlying mechanisms for microbial assembly between upper and lower soil strata under warming scenarios.
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Although autotrophic phytoplankton and heterotrophic zooplankton both play important roles in the food web of marine ecosystem, their comprehensive interactions and spatial patterns at continental scale remain poorly studied. Here, we collected 251 seawater samples along 13,000 km of Chinese coastline, and microscopically investigated the latitudinal gradients of planktonic diversities. In total, 307 phytoplanktonic and 311 zooplanktonic species were visually identified. Using the newly developed Inter-Domain Ecological Networks (IDENs) approach, the phytoplankton-zooplankton interaction networks were constructed. We found that the phyto-zooplankton network structure was varied across three regions, more complex and numerous connections along the southern coast than in the north. In addition, some particular associations between zooplanktonic and phytoplanktonic groups were found to be localized in specific regions. Furthermore, the seawater temperature and salinity were the major driving force for shaping planktonic interaction networks. These results provide a deeper understanding of planktonic biogeography and phytoplankton-zooplankton interaction patterns.
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Fitoplancton , Zooplancton , Animales , Ecosistema , Cadena Alimentaria , PlanctonRESUMEN
Biological foaming (or biofoaming) is a frequently occurring problem in wastewater treatment plants (WWTPs) and is attributed to the overwhelming growth of filamentous bulking and foaming bacteria (BFB). Biological foaming has been intensively investigated, with BFB like Microthrix and Skermania having been identified from WWTPs and implicated in foaming. Nevertheless, studies are still needed to improve our understanding of the microbial diversity of WWTP biofoams and how microbial activities contribute to foaming. In this study, sludge foaming at the Qinghe WWTP of China was monitored, and sludge foams were investigated using culture-dependent and culture-independent microbiological methods. The foam microbiomes exhibited high abundances of Skermania, Mycobacterium, Flavobacteriales, and Kaistella. A previously unknown bacterium, Candidatus Kaistella beijingensis, was cultivated from foams, its genome was sequenced, and it was phenotypically characterized. Ca. K. beijingensis exhibits hydrophobic cell surfaces, produces extracellular polymeric substances (EPS), and metabolizes lipids. Ca. K. beijingensis abundances were proportional to EPS levels in foams. Several proteins encoded by the Ca. K. beijingensis genome were identified from EPS that was extracted from sludge foams. Ca. K. beijingensis populations accounted for 4 to 6% of the total bacterial populations in sludge foam samples within the Qinghe WWTP, although their abundances were higher in spring than in other seasons. Cooccurrence analysis indicated that Ca. K. beijingensis was not a core node among the WWTP community network, but its abundances were negatively correlated with those of the well-studied BFB Skermania piniformis among cross-season Qinghe WWTP communities. IMPORTANCE Biological foaming, also known as scumming, is a sludge separation problem that has become the subject of major concern for long-term stable activated sludge operation in decades. Biological foaming was considered induced by foaming bacteria. However, the occurrence and deterioration of foaming in many WWTPs are still not completely understood. Cultivation and characterization of the enriched bacteria in foaming are critical to understand their genetic, physiological, phylogenetic, and ecological traits, as well as to improve the understanding of their relationships with foaming and performance of WWTPs.
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Flavobacteriaceae , Aguas del Alcantarillado , Purificación del Agua , China , Flavobacteriaceae/clasificación , Flavobacteriaceae/aislamiento & purificación , Filogenia , Aguas del Alcantarillado/microbiologíaRESUMEN
The spread of antibiotic resistance genes (ARGs) has gained much attention worldwide, while the contribution of vertical gene transfer (VGT) and horizontal gene transfer (HGT) is still elusive. Here, we improved an emerging high-throughput single-cell-based technology, emulsion, paired isolation, and concatenation polymerase chain reaction (epicPCR), by lengthening the sequence of ARG in the fused ARG-16S rRNA fragments to cover the variance of both ARG and its hosts. The improved epicPCR was applied to track the hosts of a widely detected ARG, sul1 gene, in five urban wastewater treatment plants (UWTPs) during two seasons. The sul1 host bacteria were highly diverse and mostly classified as Proteobacteria and Bacteroidetes. Clear seasonal divergence of α-diversity and interaction networks were present in the host community. The consensus phylogenetic trees of the sul1 gene and their host demonstrated incorrespondence on the whole and regularity on abundant groups, suggesting the important role of both HGT and VGT, respectively. The relative importance of these two ways was further measured; HGT (54%) generally played an equal or even more important role as VGT (46%) in UWTPs. The application of the improved epicPCR technology provides a feasible approach to quantify the relative contributions of VGT and HGT in environmental dissemination of ARGs.
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Transferencia de Gen Horizontal , Purificación del Agua , Antibacterianos/farmacología , Farmacorresistencia Microbiana/genética , Filogenia , ARN Ribosómico 16S/genética , TecnologíaRESUMEN
An efficient strategy for the synthesis of pharmaceutically important and synthetically useful cyanoimines, as well as cyanamides, has been described. This strategy is enabled by dual photoredox/copper-catalyzed cyanation of O-acyl oximes or O-acyl hydroxamides. This state of the art protocol for cyanoimines and cyanamides features readily available starting materials, mild reaction conditions, good functional group tolerance, and operational simplicity. The resultant cyanoimines can be transformed into structurally diverse and functionally important N-containing heterocycles.
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The survey of microbial diversity in various environments has relied upon the widespread use of well-evaluated amplification primers for taxonomic marker genes (e.g., prokaryotic 16S and fungal ITS). However, it is urgent to develop a fast and accurate bioinformatic program to design primers for microbial functional genes to explore more mechanisms in the microbial community. Here, we provide a rapid degenerate primer design pipeline (ARDEP) based on the k-mer algorithm, which can bypass the time-consuming step of sequence alignment to greatly reduce run times while ensuring accuracy. In addition, we developed an open-access platform for the implementation of primer design projects that could also calculate the amplification product length, GC content, Annealing Temperature (Tm), and ΔG of primer self-folding, and identify covered species and functional groups. Using this new platform, we designed primers for several functional genes in the nitrogen cycle, including napA and amoA. Our newly designed primers achieved higher coverage than the commonly used primers for all tested genes. The program and the associated platform that applied the k-mer algorithm could greatly enhance the design and evaluation of primers for environmental microbiome studies.
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Microbiota , Biología Computacional , Cartilla de ADN , Hongos , Microbiota/genética , Reacción en Cadena de la PolimerasaRESUMEN
The intestinal protozoan parasite, Giardia duodenalis, infects a large number of people in the world annually. Giardia infection has been considered a negative effect on intestinal epithelial cell growth, while the underlying mechanisms remain to be explored. Here we evaluated reactive oxygen species (ROS) production and apoptotic events in Giardia trophozoites-stimulated Caco-2 cells via fluorescence microscopy, transmission electron microscopy, flow cytometry, western blot, and cell counting kit-8 analyses. The results showed that Giardia trophozoite treatment could induce lactate dehydrogenase release and Caco-2 cell apoptosis. The ROS levels were increased post treatment. The observed typical characteristics of mitochondria damage include significant swelling and degeneration of matrix and cristae. After trophozoite treatment, the level of Bax protein expression was increased, while Bcl-2 protein decreased. Trophozoite stimulation also led to reduction of mitochondrial membrane potential and release of cytochrome c from the mitochondria to the cytoplasm, and this process was accompanied by activation of caspase-9 and caspase-3 and poly (ADP-ribose) polymerase 1 cleavage. Pretreatment with N-acetyl-L-cysteine, a ROS inhibitor, reversed G. duodenalis-induced Caco-2 cell apoptosis. Taken together, we indicated that G. duodenalis could induce Caco-2 cell apoptosis through a ROS- and mitochondria-mediated caspase-dependent pathway. This study furthers our understanding of the cellular mechanism of the interaction between Giardia trophozoites and host cells.
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Blastocystis is of public health concern due to its global distribution in diverse animals including humans. Here, fecal specimens sampled from human and nonhuman primates were examined for Blastocystis by PCR and sequence analysis of the small subunit ribosomal RNA gene. Among age cohorts, the parasite was positive only for three of 126 (2.4%) adults admitted to a hospital in Harbin, Heilongjiang province, with a less common human subtype (ST), ST5, determined. Blastocystis was identified in 7.0% of nonhuman primates (NHPs), giving an infection rate of 6.8% (4/59) to zoo NHPs in Harbin and 7.1% (9/126) to lab NHPs in Beijing. No significant prevalence differences by macaque species, age, gender, and sample source were observed. Among the subtypes found in NHPs, seven belonged to ST1, three to ST2, one to ST3, and the remaining two to mixed ST1/ST3 and ST2/ST3. Although the data here showed no direct evidence linking human infections to Blastocystis of NHP origin, individuals might acquire colonization of ST5 from livestock sources judged by occurrence of this subtype also in cattle in Harbin and pigs and sheep in unspecified cities of Heilongjiang as noted in previous reports. In addition, given the nonrigid (but sometimes, perhaps cryptic) host specificity of ST1, ST2, and ST3 and their dominant role in human affections globally as discussed in a previous NHP report by Alfellani et al. (Parasitology 140:966-971, 2013a), precautions should be taken to minimize the possible transmission of those subtypes from NHPs to humans in North China.
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Infecciones por Blastocystis/epidemiología , Infecciones por Blastocystis/parasitología , Blastocystis/genética , Primates/parasitología , Animales , Blastocystis/clasificación , Blastocystis/aislamiento & purificación , Infecciones por Blastocystis/transmisión , China/epidemiología , Heces/parasitología , Variación Genética , Genotipo , Humanos , PrevalenciaRESUMEN
Giardia duodenalis is one of main causative agents of diarrhea that affects the health of millions of people on a global scale per year. It has been clear that attachment of G. duodenalis trophozoites to intestinal epithelium cells (IECs) can induce cell death, while the underlying cellular and molecular mechanisms remain to be explored. It was shown in this study that treatment of Caco-2 cells with Giardia trophozoites could result in reduced cell viability. RNA sequencing analysis demonstrated that expressions of many apoptosis-related genes and some deubiquitinase genes displayed marked changes in trophozoite-treated cells. Trophozoites activated the death-signaling receptor TNFR1 on the IEC surface and caspase-3/8 (CASP3/8) signaling pathways in Caco-2 cells. K63 ubiquitination level of RIP1 was reduced upon stimulation with trophozoites, in parallel, the expressions of deubiquitinases CYLD and A20 were increased. The caspase inhibitor Q-VD-OPH could rescue trophozoite-induced cell apoptosis. Likewise, TNFR1, CYLD, and A20 silencing decreased the levels of cleaved CASP3/8 in trophozoite-treated cells and reversed the pro-apoptosis induction effect of trophozoites. These data suggest that Giardia trophozoite stimulation can activate CASP3/8 signaling pathways via activation of TNFR1 and K63 de-ubiquitination of RIP1 caused by up-regulated expressions of CYLD and A20, and promote Caco-2 cell apoptosis. The present study deepens our understanding of the mechanism of interaction between Giardia and IECs.
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Apoptosis , Células Epiteliales , Giardia lamblia , Proteínas de Complejo Poro Nuclear/metabolismo , Proteínas de Unión al ARN/metabolismo , Receptores Tipo I de Factores de Necrosis Tumoral/metabolismo , Células CACO-2 , Células Epiteliales/metabolismo , Células Epiteliales/parasitología , Humanos , UbiquitinaciónRESUMEN
Biodiversity is the foundation of all ecosystems across the planet, and having a better understanding of its global distribution mechanism could be important for biodiversity conservation under global change. A niche width model, combined with metabolic theory, has successfully predicted the increase of α-diversity and decrease of ß-diversity in the below-ground microbial community along an altitudinal mountain gradient. In this study, we evaluated this niche width model of above-ground plants (mainly trees and shrubs) and below-ground bulk soil microbial communities (i.e., bacteria and archaea) along a latitudinal gradient of forests in China. The niche widths of both plants and microbes increased with increasing temperature and precipitation, and with proximity to circumneutral pH. However, the α- and ß-diversities (observed richness and Bray-Curtis dissimilarity, respectively) could not be accurately predicted by a single niche width model alone, either temperature, precipitation or pH. Considering the interactions among different niche width models, all three niche width models were combined to predict biodiversity at the community level using structural equation modelling. The results showed that the niche width model of circumneutral pH was most important in predicting diversity profiling (i.e., α- and ß-diversity) for both plants and microbes, while niche width of precipitation and temperature showed both direct and indirect importance for microbe and plant biodiversity, respectively. Because the current niche width model neglects several scenarios related to taxon and environmental attributes, it still needs to be treated with caution in predicting biodiversity trends.
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Biodiversidad , Ecosistema , Microbiología del Suelo , China , Bosques , Plantas , SueloRESUMEN
A novel strain, designated AQ6-296T, was isolated from a soil sample collected in Fildes Peninsula, Antarctic. Cells were Gram-stain-negative, non-endospore-forming, non-motile, strictly aerobic and rod-shaped. Growth occurred at 4-28 °C (optimum, 20 °C) and at pH 6.0-7.0 (optimum, pH 7.0). NaCl was not obligatory for growth. Colonies were pale yellow after growth for 3 days at 20 °C on Reasoner's 2A agar. The strain was weakly positive for oxidase and the catalase test was negative. The only respiratory quinone was Q-8. The predominant cellular fatty acids were iso-C16â:â0, iso-C15â:â0, iso-C11â:â0 3OH, summed feature 3 (comprising C16â:â1ω7c and/or C16â:â1ω6c) and summed feature 9 (comprising iso-C17â:â1ω9c and/or C16â:â010-methyl). The major polar lipids were phosphatidylethanolamine, unknown aminolipids, phosphatidylglycerol and diphosphatidylglycerol. The results of phylogenetic analysis based on 16S rRNA gene sequences (the highest similarity at 92.4â% to Lysobacter dokdonensis) indicated that strain AQ6-296T is within the family Xanthomonadaceae. The DNA G+C content of the type strain was 58.6 mol%. On the basis of phenotypic, chemotaxonomic and phylogenetic data, strain AQ6-296T is considered to represent a novel genus and species in the family Xanthomonadaceae, for which the name Pseudolysobacter antarcticus gen. nov., sp. nov. is proposed. The type strain is AQ6-296T (CCTCC AB 2016313T=KCTC 52744T).
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Filogenia , Microbiología del Suelo , Xanthomonadaceae/clasificación , Regiones Antárticas , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Ubiquinona/química , Xanthomonadaceae/aislamiento & purificaciónRESUMEN
In the original publication, the deposit number of strain sh-6T was incorrectly published as "CCTCC AB 2016064" throughout the article.
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Strain YZ-8T, isolated from soil sampled at Fildes Peninsula, Antarctica, was found to be a Gram-stain-negative, yellow-pigmented, oxidase- and catalase-positive, non-motile, non-spore-forming, rod-shaped and aerobic bacterium. Strain YZ-8T grewoptimally at pH 7.0 and 20 °C. Tolerance to NaCl was up to 0.3â% (w/v) with optimum growth in the absence of NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain YZ-8T belonged to the family Sphingomonas. Strain YZ-8T showed the highest sequence similarities to Sphingomonas molluscorum KMM 3882T (94.4â%), Sphingomonas oligophenolica JCM 12082T (94.4â%), Sphingomonas gotjawalisoli SN6-9T (94.3â%) and Sphingomonas aquatica W1-2-1T (94.3â%). The predominant respiratory isoprenoid quinone and polyamine components were identified as ubiquinone Q-10 and sym-homospermidine, respectively. In addition, carotenoid were also found. The polar lipid profile of the strain YZ-8T was found to contain one phosphatidylethanolamine, an unidentified phospholipid, one diphosphatidylglycerol, one phosphatidylglycerol, two sphingophosphonolipids, one phosphatidylcholine and two unidentified alkali-stable lipids. The G+C content of the genomic DNA was determined to be 58.8 mol%. The main fatty acids were summed feature 8 (comprising C18â:â1ω7c and/or C18â:â1ω6c; 35.4â%), summed feature 3 (comprising C16â:â1ω7c and/or C16â:â1ω6c; 32.6â%) and C14â:â0 2-OH (7.7â%). On the basis of the evidence presented in this study, a novel species of the genus Sphingomonas, Sphingomonaspaeninsulae sp. nov., is proposed, with the type strain YZ-8T (=CCTCC AB 2017137T=LMG 31027T).