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1.
Nat Commun ; 12(1): 1732, 2021 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-33741980

RESUMEN

Macrolides are a class of antibiotics widely used in both medicine and agriculture. Unsurprisingly, as a consequence of their exensive usage a plethora of resistance mechanisms have been encountered in pathogenic bacteria. One of these resistance mechanisms entails the enzymatic cleavage of the macrolides' macrolactone ring by erythromycin esterases (Eres). The most frequently identified Ere enzyme is EreA, which confers resistance to the majority of clinically used macrolides. Despite the role Eres play in macrolide resistance, research into this family enzymes has been sparse. Here, we report the first three-dimensional structures of an erythromycin esterase, EreC. EreC is an extremely close homologue of EreA, displaying more than 90% sequence identity. Two structures of this enzyme, in conjunction with in silico flexible docking studies and previously reported mutagenesis data allowed for the proposal of a detailed catalytic mechanism for the Ere family of enzymes, labeling them as metal-independent hydrolases. Also presented are substrate spectrum assays for different members of the Ere family. The results from these assays together with an examination of residue conservation for the macrolide binding site in Eres, suggests two distinct active site archetypes within the Ere enzyme family.


Asunto(s)
Antibacterianos/química , Farmacorresistencia Bacteriana/efectos de los fármacos , Farmacorresistencia Bacteriana/genética , Esterasas/química , Esterasas/genética , Macrólidos/química , Antibacterianos/farmacología , Bacterias/enzimología , Bacterias/genética , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Sitios de Unión , Hidrolasas de Éster Carboxílico/química , Hidrolasas de Éster Carboxílico/genética , Hidrolasas de Éster Carboxílico/metabolismo , Eritromicina/química , Genes Bacterianos , Macrólidos/farmacología , Simulación del Acoplamiento Molecular , Conformación Proteica , Difracción de Rayos X
2.
Bioresour Technol ; 329: 124924, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33691205

RESUMEN

For exploring the impact of temperature on antibiotic resistant genes (ARGs) during sludge anaerobic digestion (AD), the dynamic variations of sludge ARGs, plasmid ARGs, and cell-free ARGs in mesophilic (25 °C and 35 °C) and thermophilic (55 °C) digesters were investigated. The study revealed that the abundance of sludge ARGs and plasmid ARGs in thermophilic sludge AD was significantly lower than that in mesophilic digesters, while the cell-free ARGs abundance of the thermophilic digesters was similar to mesophilic digesters. Higher archaea abundance, lower bacteria abundance, and different microbial community were found in thermophilic digesters compared to that of mesophilic ones. Firmicutes might be a main group of potential hosts of ARGs in sludge AD. The distinct microbial community was the main contributor to the low ARGs abundance in thermophilic sludge AD. Thermophilic operation at 55 °C rather than mesophilic operation is more conducive to control ARGs in sludge anaerobic digestion.


Asunto(s)
Antibacterianos , Aguas del Alcantarillado , Anaerobiosis , Antibacterianos/farmacología , Bacterias/genética , Farmacorresistencia Microbiana/genética , Temperatura
3.
Sci Total Environ ; 772: 145386, 2021 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-33770858

RESUMEN

Soil organic matter (SOM) is related to vegetation, soil bacteria, and soil properties; however, not many studies link all these parameters simultaneously, particularly in tundra ecosystems vulnerable to climate change. Our aim was to describe the relationships between vegetation, bacteria, soil properties, and SOM composition in moist acidic tundra by integrating physical, chemical, and molecular methods. A total of 70 soil samples were collected at two different depths from 36 spots systematically arranged over an area of about 300 m × 50 m. Pyrolysis-gas chromatography/mass spectrometry and pyrosequencing of the 16S rRNA gene were used to identify the molecular compositions of the SOM and bacterial community, respectively. Vegetation and soil physicochemical properties were also measured. The sampling sites were grouped into three, based on their SOM compositions: Sphagnum moss-derived SOM, lipid-rich materials, and aromatic-rich materials. Our results show that SOM composition is spatially structured and linked to microtopography; however, the vegetation, soil properties, and bacterial community composition did not show overall spatial structuring. Simultaneously, soil properties and bacterial community composition were the main factors explaining SOM compositional variation, while vegetation had a residual effect. Verrucomicrobia and Acidobacteria were related to polysaccharides, and Chloroflexi was linked to aromatic compounds. These relationships were consistent across different hierarchical levels. Our results suggest that SOM composition at a local scale is closely linked with soil factors and the bacterial community. Comprehensive observation of ecosystem components is recommended to understand the in-situ function of bacteria and the fate of SOM in the moist acidic tundra.


Asunto(s)
Ecosistema , Suelo , Alaska , Bacterias/genética , ARN Ribosómico 16S/genética , Microbiología del Suelo , Tundra
4.
Bioresour Technol ; 330: 124970, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33735726

RESUMEN

Currently, anaerobic sludge digestion (ASD) is considered not only for treating residual sewage sludge and energy recovery but also for the reduction of antibiotic resistance genes (ARGs). The current review highlights the reasons why antibiotic resistant bacteria (ARB) and ARGs exist in ASD and how ASD performs in the reduction of ARB and ARGs. ARGs and ARB have been detected in ASD with some reports indicating some of the ARGs can be completely removed during the ASD process, while other studies reported the enrichment of ARB and ARGs after ASD. This paper reviews the performance of ASD based on operational parameters as well as environmental chemistry. More studies are needed to improve the performance of ASD in reducing ARGs that are difficult to handle and also differentiate between extracellular (eARGs) and intracellular ARGs (iARGs) to achieve more accurate quantification of the ARGs.


Asunto(s)
Genes Bacterianos , Aguas del Alcantarillado , Anaerobiosis , Antagonistas de Receptores de Angiotensina , Inhibidores de la Enzima Convertidora de Angiotensina , Antibacterianos/farmacología , Bacterias/genética , Digestión , Farmacorresistencia Microbiana/genética , Aguas Residuales
5.
Bioresour Technol ; 330: 124990, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33756181

RESUMEN

The influence of three additives including Camellia oleifera meal, C. oleifera seed cake and goat dung during the C. oleifera shell composting was evaluated. The result of physic-chemical parameters indicated that compost of C. oleifera shell with one of additives could achieve the effect of maturity.16S rDNA sequencing suggested that Proteobacteria, Bacteroidetes, Firmicutes, Actinobacteria, Chloroflexi, Tenericutes, Deinococcus-Thermus, Patescibacteria, Fibrobacteres and Acidobacteria were the dominant microorganisms in all compost piles, and their abundances varied with compost additive and composting phase. Goat dung significantly increased the microbial diversity at the mesophilic phase. The microbial composition was most diverse at the end of composting for all piles. No pathogens were detected in the compost products of all three groups, and thus were safe for utilization in plant cultivation. This work considered that compost was best way to address the contamination problem of C. oleifera shell, where goat dung was best additive for compost.


Asunto(s)
Camellia , Compostaje , Animales , Bacterias/genética , Heces , Estiércol , Suelo , Microbiología del Suelo
6.
Huan Jing Ke Xue ; 42(4): 1923-1929, 2021 Apr 08.
Artículo en Chino | MEDLINE | ID: mdl-33742827

RESUMEN

The specific ammonia uptake rates (SAUR) and ammonia oxidizing bacteria (AOB) community of influent sewage and activated sludge in the 2nd wastewater treatment plant (WWTP) of Xi'an without the primary settling tank were analyzed over multiple years to explore the seasonal effects of the influent AOB on the activated sludge systems. During the experiment, the SAUR of the raw sewage and activated sludge were 0.48-3.02 mg·(g·h)-1 and 0.68-2.25 mg·(g·h)-1, respectively. Meanwhile, the correlation analysis indicated that the monthly SAUR of the raw sewage was highly correlated with that of the activated sludge of the following month (r=0.862,P<0.05), which indicated that influent nitrifiers had a significant effect on the nitrification performance of activated sludge. Considering that the estimated AOB seeding intensities based on the ammonia oxidizing activity were 0.21-0.92 g·(g·d)-1, the nitrifier immigration from the raw sewage should added to the design of WWTP and the activated sludge modeling. Moreover, the qPCR results revealed that the AOB abundance of activated sludge in winter decreased but remained at 1010 cells·g-1, indicating that the immigration of influent nitrifiers could partially compensate for the reduction of the AOB abundance in the activated sludge caused by decreasing temperatures. Finally, the Illumina MiSeq sequencing demonstrated that the shared dominant AOB between the raw sewage and activated sludge were Nitrosomonas sp. Nm58, Nitrosomonas sp. JL21, and bacterium CYCU-0253. These findings can provide theoretical support for the design and operation of a WWTP.


Asunto(s)
Aguas del Alcantarillado , Purificación del Agua , Amoníaco , Bacterias/genética , Reactores Biológicos , Nitrificación , Oxidación-Reducción , Estaciones del Año
7.
Science ; 371(6536)2021 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-33766858

RESUMEN

Microbial roles in cancer formation, diagnosis, prognosis, and treatment have been disputed for centuries. Recent studies have provocatively claimed that bacteria, viruses, and/or fungi are pervasive among cancers, key actors in cancer immunotherapy, and engineerable to treat metastases. Despite these findings, the number of microbes known to directly cause carcinogenesis remains small. Critically evaluating and building frameworks for such evidence in light of modern cancer biology is an important task. In this Review, we delineate between causal and complicit roles of microbes in cancer and trace common themes of their influence through the host's immune system, herein defined as the immuno-oncology-microbiome axis. We further review evidence for intratumoral microbes and approaches that manipulate the host's gut or tumor microbiome while projecting the next phase of experimental discovery.


Asunto(s)
Fenómenos Fisiológicos Bacterianos , Microbiota , Neoplasias/microbiología , Neoplasias/terapia , Inmunidad Adaptativa , Antibacterianos/uso terapéutico , Antineoplásicos/uso terapéutico , Bacterias/genética , Carcinogénesis , Microbioma Gastrointestinal , Ingeniería Genética , Interacciones Microbiota-Huesped , Humanos , Inmunomodulación , Inmunoterapia , Tejido Linfoide/inmunología , Neoplasias/inmunología , Viroterapia Oncolítica , Microambiente Tumoral , Fenómenos Fisiológicos de los Virus
8.
Nat Commun ; 12(1): 1926, 2021 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-33771992

RESUMEN

The stomach is inhabited by diverse microbial communities, co-existing in a dynamic balance. Long-term use of drugs such as proton pump inhibitors (PPIs), or bacterial infection such as Helicobacter pylori, cause significant microbial alterations. Yet, studies revealing how the commensal bacteria re-organize, due to these perturbations of the gastric environment, are in early phase and rely principally on linear techniques for multivariate analysis. Here we disclose the importance of complementing linear dimensionality reduction techniques with nonlinear ones to unveil hidden patterns that remain unseen by linear embedding. Then, we prove the advantages to complete multivariate pattern analysis with differential network analysis, to reveal mechanisms of bacterial network re-organizations which emerge from perturbations induced by a medical treatment (PPIs) or an infectious state (H. pylori). Finally, we show how to build bacteria-metabolite multilayer networks that can deepen our understanding of the metabolite pathways significantly associated to the perturbed microbial communities.


Asunto(s)
Microbioma Gastrointestinal/efectos de los fármacos , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori/efectos de los fármacos , Aprendizaje Automático , Microbiota/efectos de los fármacos , Inhibidores de la Bomba de Protones/uso terapéutico , Bacterias/clasificación , Bacterias/genética , Bacterias/metabolismo , Infecciones por Helicobacter/microbiología , Helicobacter pylori/fisiología , Humanos , Dinámica Poblacional , ARN Ribosómico 16S/genética , Estómago/microbiología
9.
Environ Sci Process Impacts ; 23(3): 491-500, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33647083

RESUMEN

The objective of this analysis was to examine and compare quantitative metrics of observed dampness and mold, including visible mold and moisture damage, and fungal and bacterial microbiomes. In-home visits were conducted at age 7 for children enrolled in the Cincinnati Childhood Allergy and Air Pollution Study. Trained study staff evaluated the primary residence and measured total areas of visible moisture and mold damage in the home. Floor dust was collected and archived. Archived dust samples collected from each home (n = 178) were extracted and analyzed using bacterial (16S rRNA gene) and fungal (internal transcribed spacer region) sequencing. Fungi were also divided into moisture requirement categories of xerophiles, mesophiles, and hydrophiles. Data analyses used Spearman's correlation, Kruskal-Wallis, Permanova, DESeq, and negative binomial regression models. Comparing high moisture or mold damage to no damage, five fungal species and two bacterial species had higher concentrations (absolute abundance) and six fungal species and three bacterial species had lower concentrations. Hydrophilic and mesophilic fungi showed significant dose-related increases with increasing moisture damage and mold damage, respectively. When comparing alpha or beta diversity of fungi and bacteria across mold and moisture damage levels, no significant associations or differences were found. Mold and moisture damage did not affect diversity of fungal and bacterial microbiomes. Instead, both kinds of damage were associated with changes in species composition of both bacterial and fungal microbiomes, indicating that fungal and bacterial communities in the home might be influenced by one another as well as by mold or moisture in the home.


Asunto(s)
Contaminación del Aire Interior , Microbiota , Contaminación del Aire Interior/análisis , Bacterias/genética , Niño , Polvo/análisis , Hongos/genética , Vivienda , Humanos , ARN Ribosómico 16S
10.
Environ Pollut ; 276: 116704, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33652188

RESUMEN

Antibiotic resistance genes (ARGs) are emerging contaminants in the environment and have been highlighted as a worldwide environmental and health concern. As important participants in the biogeochemical cycles, mangrove ecosystems are subject to various anthropogenic disturbances, and its microbiota may be affected by various contaminants such as ARGs. This study selected 13 transects of mangrove-covered areas in Hainan, China for sediment sample collection. The abundance and diversity of ARGs and mobile genetic elements (MGEs) were investigated using high-throughput quantitative polymerase chain reaction (HT-qPCR), and high-throughput sequencing was used to study microbial structure and diversity. A total of 179 ARGs belonging to 9 ARG types were detected in the study area, and the detection rates of vanXD and vatE-01 were 100%. The abundance of ARGs was 8.30 × 107-6.88 × 108 copies per g sediment (1.27 × 10-2-3.39 × 10-2 copies per 16S rRNA gene), which was higher than similar studies, and there were differences in the abundance of ARGs in these sampling transects. The multidrug resistance genes (MRGs) accounted for the highest proportion (69.0%), which indicates that the contamination of ARGs in the study area was very complicated. The ARGs significantly positively correlated with MGEs, which showed that the high level of ARGs was related to its self-enhancement. The dominant bacteria at the genus level were Desulfococcus, Clostridium, Rhodoplanes, Bacillus, Vibrio, Enterococcus, Sedimentibacter, Pseudoalteromonas, Paracoccus, Oscillospira, Mariprofundus, Sulfurimonas, Aminobacterium, and Novosphingobium. There was a significant positive correlation between 133 bacterial genera and some ARGs. Chthoniobacter, Flavisolibacter, Formivibrio, Kaistia, Moryella, MSBL3, Perlucidibaca, and Zhouia were the main potential hosts of ARGs in the sediments of Hainan mangrove area, and many of these bacteria are important participants in biogeochemical cycles. The results contribute to our understanding of the distribution and potential hosts of ARGs and provide a scientific basis for the protection and management of Hainan mangrove ecosystem.


Asunto(s)
Antibacterianos , Genes Bacterianos , Antibacterianos/farmacología , Bacterias/genética , China , Farmacorresistencia Microbiana/genética , Humanos , Islas , ARN Ribosómico 16S
11.
Water Res ; 196: 117037, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33751976

RESUMEN

The establishment of a sessile community is believed to occur in a sequence of steps where genetically distinct bacteria can become attached to partner cells via specific molecules, in a process known as coaggregation. The presence of bacteria with the ability to autoaggregate and coaggregate has been described for diverse aquatic systems, particularly freshwater, drinking water, wastewater, and marine water. In these aquatic systems, coaggregation already demonstrated a role in the development of complex multispecies sessile communities, including biofilms. While specific molecular aspects on coaggregation in aquatic systems remain to be understood, clear evidence exist on the impact of this mechanism in multispecies biofilm resilience and homeostasis. The identification of bridging bacteria among coaggregating consortia has potential to improve the performance of wastewater treatment plants and/or to contribute for the development of strategies to control undesirable biofilms. This study provides a comprehensive analysis on the occurrence and role of bacterial coaggregation in diverse aquatic systems. The potential of this mechanism in water-related biotechnology is further described, with particular emphasis on the role of bridging bacteria.


Asunto(s)
Bacterias , Adhesión Bacteriana , Bacterias/genética , Biopelículas , Agua Dulce
12.
Yi Chuan ; 43(3): 240-248, 2021 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-33724208

RESUMEN

As the most abundant biological entities on earth, bacteriophages (phages) were considered as the antagonists of bacteria. With the rapid development of genomics and molecular biology technologies, a subtle and complex relationship between phages and their host bacteria has been uncovered. Prophage refers to an intracellular form of a bacteriophage, which is usually integrated into the hereditary material of the host. Prophage is ubiquitously distributed in bacterial genomes. It reproduces when the host does and can affect important biological properties of their bacterial hosts, such as virulence, biofilm formation and host immunity. Interestingly, prophages were also involved in regulating the lysogeny-lytic state by "monitoring" the quorum sensing of bacteria. Recently, anti-CRISPR proteins encoded by prophages were found, which attracts a lot of attention. In this review, we summarized the prediction, distribution, classification and functions of prophages to lay a foundation for further studying interactions between phages and bacteria.


Asunto(s)
Bacteriófagos , Profagos , Bacterias/genética , Bacteriófagos/genética , Genoma Bacteriano , Lisogenia/genética , Profagos/genética
13.
Yi Chuan ; 43(2): 142-159, 2021 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-33724217

RESUMEN

Bacteria with the smallest genome contain genes necessary for self-sustaining replication only, giving the organisms advantages to serve as a potential industrial production platform. Many strains with reduced genomes have been constructed, owing to the development of high-throughput DNA sequencing and synthesis technology. This review first describes the concept of minimal genomes, summarizes the relevant research progress of bacterial essential genes, then systematically lists the work related to artificial reduction and synthesis of bacterial genomes, finally discusses the technical obstacles and limitations encountered in the process of designing and constructing reduced genomes, hoping to provide a theoretical basis for the experiment and application of artificially synthesized genomes.


Asunto(s)
Genes Esenciales , Genoma Bacteriano , Bacterias/genética , Genes Bacterianos , Genoma Bacteriano/genética
14.
Sheng Wu Gong Cheng Xue Bao ; 37(3): 874-910, 2021 Mar 25.
Artículo en Chino | MEDLINE | ID: mdl-33783156

RESUMEN

The development and implement of microbial chassis cells can provide excellent cell factories for diverse industrial applications, which help achieve the goal of environmental protection and sustainable bioeconomy. The synthetic biology strategy of Design-Build-Test-Learn (DBTL) plays a crucial role on rational and/or semi-rational construction or modification of chassis cells to achieve the goals of "Building to Understand" and "Building for Applications". In this review, we briefly comment on the technical development of the DBTL cycle and the research progress of a few model microorganisms. We mainly focuse on non-model bacterial cell factories with potential industrial applications, which possess unique physiological and biochemical characteristics, capabilities of utilizing one-carbon compounds or of producing platform compounds efficiently. We also propose strategies for the efficient and effective construction and application of synthetic microbial cell factories securely in the synthetic biology era, which are to discover and integrate the advantages of model and non-model industrial microorganisms, to develop and deploy intelligent automated equipment for cost-effective high-throughput screening and characterization of chassis cells as well as big-data platforms for storing, retrieving, analyzing, simulating, integrating, and visualizing omics datasets at both molecular and phenotypic levels, so that we can build both high-quality digital cell models and optimized chassis cells to guide the rational design and construction of microbial cell factories for diverse industrial applications.


Asunto(s)
Ingeniería Metabólica , Biología Sintética , Bacterias/genética
15.
Nat Commun ; 12(1): 1475, 2021 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-33674569

RESUMEN

Accurate measurements of promoter activities are crucial for predictably building genetic systems. Here we report a method to simultaneously count plasmid DNA, RNA transcripts, and protein expression in single living bacteria. From these data, the activity of a promoter in units of RNAP/s can be inferred. This work facilitates the reporting of promoters in absolute units, the variability in their activity across a population, and their quantitative toll on cellular resources, all of which provide critical insights for cellular engineering.


Asunto(s)
Bacterias/genética , Variaciones en el Número de Copia de ADN , Plásmidos , Escherichia coli/genética , Regulación Bacteriana de la Expresión Génica , Regiones Promotoras Genéticas , ARN Mensajero/metabolismo , Transcripción Genética
16.
J Environ Manage ; 287: 112279, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33706095

RESUMEN

Environment pollution is at its peak and is creating havoc for living beings. Industrial wastes containing toxic pollutants have contributed to a great extent in this disastrous environment pollution. Chromium (Cr3+/Cr6+) is highly toxic and one of the most common environmental pollutants because of its extensive use in industries especially tanneries. Lack of efficient treatment methods has resulted in extensive chromium pollution. Bioremediation of chromium using bacteria is very thoughtful due to its eco-friendly and cost-effective outcome. Bacteria possess numerous mechanisms such as biosorption, reduction, efflux or bioaccumulation, naturally or acquired to counter the toxicity of chromium. This review focuses on the bacterial responses against chromium toxicity and scope for their application in bioremediation. The differences and similarities between Gram negative and positive bacteria against chromium are also highlighted. Further, the knowledge gap and future prospects are also discussed in order to fill these gaps and overcome the problem associated with real-time applicability of bacterial bioremediation.


Asunto(s)
Cromo , Contaminantes Ambientales , Bacterias/genética , Biodegradación Ambiental , Cromo/análisis , Cromo/toxicidad , Contaminantes Ambientales/análisis , Residuos Industriales
17.
Animal ; 15(3): 100161, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33785185

RESUMEN

Feed efficiency is a highly important economic trait in sheep production and has a significant impact on the economic benefits of sheep farming. Microbial fermentation of the rumen has a vital role in the host's nutrition; the rumen microbiota might affect host feed efficiency. However, the relationship between the rumen microbiota and feed efficiency in sheep is unclear. In the present study, the microbiota of 195 Hu sheep was investigated and their residual feed intake (RFI), a commonly used measure of feed efficiency, was determined. From birth, all sheep were subjected to the same management practices. At slaughter, samples of liquid rumen contents were collected and subjected to amplicon sequencing for the 16S rDNA gene on the IonS5™XL platform. To identify the bacterial taxa differentially represented at the genus or higher taxonomy levels, we used linear discriminant analysis coupled with effect size and curve fitting. In the sheep rumen, the four most abundant phyla were Firmicutes, Bacteroidetes, Fibrobacteres, and Proteobacteria; and the dominant genera were unidentified Prevotellaceae, Fibrobacter, unidentified Lachnospiraceae, Saccharofermentans, and Succinivibrio. Pathway analysis of the 16S rDNA sequencing data from the rumen microbiota identified that carbohydrate metabolism was enriched. Using α-diversity analysis, we further identified that Observed species, ACE, Good's coverage, and Chao1 are more abundant (P < 0.01) in the low-RFI (L-RFI) group compared to the high-RFI (H-RFI) group. High-RFI sheep had a higher abundance of three bacterial taxa (Prevotellaceae, Negativicutes, and Selenomonadales), and one taxa was overrepresented in the L-RFI sheep (Succinivibrio), respectively. Furthermore, model fitting showed that Veillonellaceae, Sphaerochaeta, Negativibacillus, Saccharofermentans, and members of the Tenericutes, Kiritimatiellaeota, Deltaproteobacteria, and Campylobacterales were correlated with the sheep RFI classification and thus were indicative of a role in animal efficiency. Tax4Fun analysis revealed that metabolic pathways such as "energy metabolism," "metabolism of cofactors and vitamins," "poorly characterized," and "replication recombination and repair proteins" were enriched in the rumen from H-RFI sheep, and "genetic information processing" and "lipopolysaccharide biosynthesis" were overrepresented in L-RFI sheep rumen. In addition, six Kyoto Encyclopedia of Genes and Genomes orthology pathways were identified as different between H-RFI and L-RFI groups. In conclusion, the low RFI phenotype (efficient animals) consistently (or characteristically) exhibited a more abundant and diverse microbiome in sheep.


Asunto(s)
Microbiota , Rumen , Alimentación Animal/análisis , Animales , Bacterias/genética , Ingestión de Alimentos , Ovinos
18.
Zhongguo Zhong Yao Za Zhi ; 46(4): 915-922, 2021 Feb.
Artículo en Chino | MEDLINE | ID: mdl-33645097

RESUMEN

The wild resources of Paris polyphylla var. yunnanensis, a secondary endangered medicinal plant, are severely scarce. Introduction and cultivation can alleviate market demand. To screen phosphatolytic bacteria in the rhizosphere soil of P. polyphylla var. yunnanensis and provide data support for the development of high-efficiency microbial fertilizer, in this study, the dilution plate coating method was used to isolate and screen the phosphorus solubilizing bacteria with the ability of mineralizing organic phosphorus from the rhizosphere soil of wild and transplanted varieties of P. polyphylla var. yunnanensis in 10 different locations in Yunnan, Sichuan and Guizhou. After separation and purification, the phosphatolytic capacity was analyzed by qualitative and quantitative analysis. Combined with physiological and biochemical experiments, the strains were identified using 16 S rDNA sequencing analysis. Forty one strains were selected from the rhizosphere soil of P. polyphylla var. yunnanensis from 10 different habitats. Among them, 21 strains were obtained from the rhizosphere soil of the wild variety P. polyphylla var. yunnanensis and 20 strains were obtained from the rhizosphere soil of the transplanted variety. And significance analysis found that 41 organophosphate solubilizing strains had significant differences in their ability to solubilize phosphorus. The amount of phosphate solubilizing was 0.08-67.61 mg·L~(-1), the pH value was between 4.27 and 6.82. The phosphatolytic amount of strain Y3-5 was 67.61 mg·L~(-1), and the phosphorus increase amount was 57.57 mg·L~(-1). All 41 strains were identified as Gram-positive Bacillus. Combining physiological characteristic and phylogenetic trees, Bacillus mobilis Y3-5 was finally selected as the candidate rhizosphere phosphatolytic bacteria of P. polyphylla var. yunnanensis. The distribution of phosphorus solubilizing bacteria in the rhizosphere soil of P. polyphylla var. yunnanensis was different, and there were significant diffe-rences in phosphorus solubility. Organophosphate-dissolving strain Y3-5 is expected to be a candidate strain of P. polyphylla var. yunnanensis microbial fertilizer.


Asunto(s)
Liliaceae , Bacillus , Bacterias/genética , China , Filogenia
19.
Braz J Biol ; 82: e234471, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33681897

RESUMEN

High doses of antibiotics used in hospitals can affect the microbial composition of sewers, selecting resistant bacteria. In this sense, we evaluated the antibiotic resistance profile and the multiresistant phenotype of bacteria isolated in sewage from a tertiary hospital in the interior São Paulo state, Brazil. For bacteria isolation, 10 µL of sewage samples were sown in selective culture media and the isolates were identified using VITEK-2 automatized system. The antibiotic sensitivity test was performed by disk diffusion. High percentages of resistance were found for amoxicillin, ampicillin, ceftazidime, clindamycin, vancomycin and the multidrug-resistant phenotype (MDR) was attributed to 60.7% of the isolates. Our results show bacteria classified as critical/high priority by WHO List of Priority Pathogens (Enterococcus and Staphylococcus aureus resistant to vancomycin and Enterobacteriaceae resistant to carbapenems) in hospital sewage. Therefore, the implementation of disinfection technologies for hospital sewage would reduce the bacterial load in the sewage that will reach urban wastewater treatment plants, minimizing superficial water contamination and bacterial resistance spread in the environment.


Asunto(s)
Bacterias , Aguas del Alcantarillado , Bacterias/genética , Brasil , Pruebas de Sensibilidad Microbiana , Fenotipo , Centros de Atención Terciaria
20.
Sci Total Environ ; 771: 144880, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33736123

RESUMEN

Diet is an important factor in shaping and influencing both an insect's phenotype and gut bacterial community, which commonly establishes diversely symbiotic interactions with the host. Efforts to leverage the connection between diet, insects, and gut microbiome primarily focus on how diet alters insect's phenotype or gut microbial composition and relatively few studies have illuminated the link between the diet-induced insect phenotypic difference and variation of gut microbiota. Mirids bugs, Adelphocoris suturalis, are plant sap-feeding omnivores that sometimes complementarily prey on other insects, like aphids (the dietary regime is referred to hereafter as balanced diet). In this study, we found that an imbalanced diet (exclusive ingestion of aphids) induced significantly higher mortality in A. suturalis (86.66%). Further gut microbial community analysis showed that the dietary difference significantly changed both the abundance and composition of the bug's gut microbiome. Most notably, an abundance of entomopathogenic Serratia bacteria in the A. suturalis gut was positively correlated with the proportion of aphids in A. suturalis diet, and Serratia marcescens was found to transfer into the hemocoels of carnivorous bugs. Injection of S. marcescens to the hemocoels further confirmed its detrimental effect to the bugs. Collectively, our study suggests that the diet-altered variation of gut microbiota may be detrimental to host insect, advancing the knowledge of omnivorous insects' strategy in forage allocation of different foods.


Asunto(s)
Microbioma Gastrointestinal , Microbiota , Animales , Bacterias/genética , Dieta , ARN Ribosómico 16S
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