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Frontiers in Microbiology 2023Diels et Gilg, commonly known as Sanyeqing (SYQ), is an important traditional Chinese medicine. The content of bioactive constituents varies in different cultivars of...
Diels et Gilg, commonly known as Sanyeqing (SYQ), is an important traditional Chinese medicine. The content of bioactive constituents varies in different cultivars of SYQ. In the plant growth related researches, rhizosphere microbiome has gained significant attention. However, the role of bacterial communities in the accumulation of metabolites in plants have not been investigated. Herein, the composition of bacterial communities in the rhizosphere soils and the metabolites profile of different SYQ cultivars' roots were analyzed. It was found that the composition of microbial communities varied in the rhizosphere soils of different SYQ cultivars. The high abundance of , and other bacteria was found to be associated with the metabolites profile of SYQ roots. The findings suggest that the upregulation of rutin and hesperetin may contribute to the high bioactive constituent in SYQ roots. These results provide better understanding of the metabolite accumulation pattern in SYQ, and also provide a solution for enhancing the quality of SYQ by application of suitable microbial consortia.
PubMed: 38163074
DOI: 10.3389/fmicb.2023.1292896 -
Frontiers in Microbiology 2024While spent mushroom substrate (SMS) has shown promise in increasing soil organic carbon (SOC) and improving soil quality, research on the interplay between SOC...
While spent mushroom substrate (SMS) has shown promise in increasing soil organic carbon (SOC) and improving soil quality, research on the interplay between SOC components and microbial community following the application of diverse SMS types remains scant. A laboratory soil incubation experiment was conducted with application of two types of SMSs from cultivation of (PE) and (AB), each at three application rates (3, 5.5, and 8%). Advanced techniques, including solid-state C nuclear magnetic resonance (NMR) and high-throughput sequencing, were employed to investigate on SOC fractions and chemical structure, microbial community composition and functionality. Compared to SMS-AB, SMS-PE application increased the relative abundances of carbohydrate carbon and O-alkyl C in SOC. In addition, SMS-PE application increased the relative abundance of the bacterial phylum Proteobacteria and those of the fungal phyla Basidiomycota and Ascomycota. The relative abundances of cellulose-degrading bacterial (e.g., and ) and fungal genera (e.g., , , and ) were increased as well. The application of SMS-AB increased the aromaticity index of SOC, the relative abundance of aromatic C, and the contents of humic acid and heavy fraction organic carbon. In addition, SMS-AB application significantly increased the relative abundances of the bacterial phyla Firmicutes and Actinobacteria. Notably, the genera , , and , which were positively correlated with humic acid, experienced an increase in relative abundance. Functional prediction revealed that SMS-PE application elevated carbohydrate metabolism and reduced the prevalence of fungal pathogens, particularly . The application of high-rate SMS-AB (8%) enhanced bacterial amino acid metabolism and the relative abundances of plant pathogenic fungi. Our research provides strategies for utilizing SMS to enrich soil organic carbon and fortify soil health, facilitating the achievement of sustainable soil management.
PubMed: 38827156
DOI: 10.3389/fmicb.2024.1351921 -
Metabolites Aug 2023Actinomycetia are known for their ability to produce a wide range of bioactive secondary metabolites having significant therapeutic importance. This study aimed to...
Actinomycetia are known for their ability to produce a wide range of bioactive secondary metabolites having significant therapeutic importance. This study aimed to explore the potential of actinomycetia as a source of bioactive compounds with antimicrobial properties against multi-drug-resistant (MDR) clinical pathogens. A total of 65 actinomycetia were isolated from two unexplored forest ecosystems, namely the Pobitora Wildlife Sanctuary (PWS) and the Deepor Beel Wildlife Sanctuary (DBWS), located in the Indo-Burma mega-biodiversity hotspots of northeast India, out of which 19 isolates exhibited significant antimicrobial activity. 16S rRNA gene sequencing was used for the identification and phylogenetic analysis of the 19 potent actinomycetia isolates. The results reveal that the most dominant genus among the isolates was (84.21%), followed by rare actinomycetia genera such as , , and . Furthermore, seventeen of the isolates tested positive for at least one antibiotic biosynthetic gene, specifically type II polyketide synthase (PKS-II) and nonribosomal peptide synthetases (NRPSs). These genes are associated with the production of bioactive compounds with antimicrobial properties. Among the isolated strains, three actinomycetia strains, namely sp. PBR1, sp. PBR36, and sp. DBR11, demonstrated the most potent antimicrobial activity against seven test pathogens. This was determined through in vitro antimicrobial bioassays and the minimum inhibitory concentration (MIC) values of ethyl acetate extracts. Gas chromatography-mass spectrometry (GS-MS) and whole-genome sequencing (WGS) of the three strains revealed a diverse group of bioactive compounds and secondary metabolite biosynthetic gene clusters (smBGCs), respectively, indicating their high therapeutic potential. These findings highlight the potential of these microorganisms to serve as a valuable resource for the discovery and development of novel antibiotics and other therapeutics with high therapeutic potential.
PubMed: 37623855
DOI: 10.3390/metabo13080911 -
Plant Disease Jan 2024Root-knot nematodes ( spp.) are one of the most economically important plant parasitic nematodes, infecting almost all cultivated plants and resulting in severe yield...
Root-knot nematodes ( spp.) are one of the most economically important plant parasitic nematodes, infecting almost all cultivated plants and resulting in severe yield losses every year. Plant growth-promoting rhizobacteria (PGPR) have been extensively used to prevent and control root-knot diseases and increase yield. In this study, the effect of a consortium of three PGPR strains ( AR156, SM21, and sp. XY21; hereafter "BBS") on root-knot disease of cucumber was evaluated. The application of BBS significantly reduced the severity of root-knot disease by 56 to 72%, increased yield by 36 to 55%, and improved fruit quality by 14 to 90% and soil properties by 1 to 90% relative to the control in the cucumber fields of the Nanjing suburb, Jiangsu Province, from 2015 to 2018. BBS altered the rhizosphere bacterial community. Compared with the control group, it significantly (false discovery rate, < 0.05) increased the abundance of 14 bacterial genera that were negatively correlated with disease severity. Additionally, the redundancy analysis suggested that BBS-treated rhizosphere soil samples were dominated by disease-suppressive bacteria, including the genera , , , , , , , , , , , , , , , and , which were positively related to total organic carbon, total nitrogen, total organic matter, dissolved organic carbon, [Formula: see text]-N, and available phosphorus contents. This suggests that BBS suppresses root-knot nematodes and improves the soil chemical properties of cucumber by altering the rhizosphere microbial community.
Topics: Rhizosphere; Microbiota; Soil; Bacillus cereus; Actinomycetales; Cucumis sativus; Carbon
PubMed: 37467122
DOI: 10.1094/PDIS-09-22-2196-RE -
Antonie Van Leeuwenhoek Jan 2024During the course of development plants form tight interactions with microorganisms inhabiting their root zone. In turn, rhizosphere bacteria, in particular members of...
During the course of development plants form tight interactions with microorganisms inhabiting their root zone. In turn, rhizosphere bacteria, in particular members of the phylum Actinomycetota, positively influence the host plant by increasing access to essential nutrients and controlling the pathogenic microorganism's population. Herein, we report the characterisation of the rhizosphere associated actinobacteria community of Phyllostachys viridiglaucescens growing in the Nikitsky Botanical Garden (Crimean Peninsula, Ukraine). The overall composition of the bacterial community was elucidated by 16S rRNA gene amplicon sequencing followed by isolation of culturable microorganisms with the focus on actinomycetes. The metagenomic approach revealed that the representatives of phylum Actinomycetota (57.1%), Pseudomonadota (20.0%), and Acidobacteriota (12.2%) were dominating in the studied microbiome with Ilumatobacter (phylum Actinomycetota) (13.1%) being the dominant genus. Furthermore, a total of 159 actinomycete isolates, belonging to eight genera of Streptomyces, Micromonospora, Nonomuraea, Arthrobacter, Actinomadura, Kribbella, Cellulosimicrobium, and Mumia, were recovered from P. viridiglaucescens rhizosphere. The isolated species were tested for antimicrobial activity. 64% of isolates were active against at least one bacterial test-culture and 7.5% against fungal test culture. In overall, the rhizosphere bacterial communities act as a great source of actinobacterial diversity with the high potential for production of new bioactive compounds.
Topics: Actinobacteria; Actinomyces; Rhizosphere; RNA, Ribosomal, 16S; Actinomycetales; Streptomyces; Poaceae; Soil Microbiology
PubMed: 38170239
DOI: 10.1007/s10482-023-01906-0 -
Environmental Research Jul 2024The aim of this study was to assess effects of MnO addition (CK-0%, T1-2% and T2-5%) on humification and bacterial community during municipal sludge (MS) composting. The...
The aim of this study was to assess effects of MnO addition (CK-0%, T1-2% and T2-5%) on humification and bacterial community during municipal sludge (MS) composting. The results suggested that MnO addition inhibited the growth of Nitrospira but stimulated Nonomuraea, Actinomadura, Streptomyces and Thermopolyspora, facilitating the lignocellulose degradation and humification with the increase in organic matter degradation by 13.8%-19.2% and humic acid content by 10.9%-20.6%. Compared to CK, the abundances of exoglucanase (EC:3.2.1.91), endo-1,4-beta-xylanase (EC:3.2.1.136) and endomannanase (EC:3.2.1.78) increased by 88-99, 52-66 and 4-15 folds, respectively. However, 5%-MnO induced the enrichment of Mizugakiibacter that harms the environment of agricultural production. The addition of 2%-MnO was recommended for MS composting. Furthermore, metabolic function analysis indicated that MnO addition altered amino acid and carbohydrate metabolism, especially enhancing propanoate metabolism and butanoate metabolism but inhibiting citrate cycle. Structural equation modeling revealed that Nonomuraea and Actinomadura were the main drivers for lignocellulose degradation. This study provided theoretical guidance in regulating humification via MnO for MS composting.
Topics: Composting; Waste Disposal, Fluid; Soil Microbiology; Biodegradation, Environmental; Soil; Actinobacteria; Actinomadura; Streptomyces; Humic Substances
PubMed: 38754608
DOI: 10.1016/j.envres.2024.119151 -
Bioresource Technology Feb 2024Phenol-rich wine grape pomace (WGP) improves the conversion of pig manure (PM) into humic acid (HA) during composting. However, the impact of using combinations of FeO...
Phenol-rich wine grape pomace (WGP) improves the conversion of pig manure (PM) into humic acid (HA) during composting. However, the impact of using combinations of FeO and biochar known to promote compost maturation remains uncertain. This research explored the individual and combined influence of biochar and FeO during the co-composting of PM and WGP. The findings revealed that FeO boosts microbial network symbiosis (3233 links), augments the HA yield to 3.38 by promoting polysaccharide C-O stretching, and improves the germination index to 124.82 %. Limited microbial interactions, increased by biochar, resulted in a lower HA yield (2.50). However, the combination weakened the stretching of aromatics and quinones, which contribute to the formation of HA, resulting in reduced the humification to 2.73. In addition, Bacillus and Actinomadura were identified as pivotal factors affecting HA content. This study highlights FeO and biochar's roles in phenol-rich compost humification, but combined use reduces efficacy.
Topics: Animals; Swine; Soil; Manure; Composting; Vitis; Humic Substances; Phenols; Microbial Interactions; Phenol; Charcoal
PubMed: 38029803
DOI: 10.1016/j.biortech.2023.130120 -
Frontiers in Plant Science 2023() is an economically important forest tree species, often cultivated in continuous monoculture as a coastal protection forest. Continuous planting has gradually...
Metagenomics-based exploration of key soil microorganisms contributing to continuously planted growth inhibition and their interactions with soil nutrient transformation.
() is an economically important forest tree species, often cultivated in continuous monoculture as a coastal protection forest. Continuous planting has gradually affected growth and severely restricted the sustainable development of the industry. In this study, we analyzed the effects of continuous planting on growth and explored the rhizosphere soil microecological mechanism from a metagenomic perspective. The results showed that continuous planting resulted in dwarfing, shorter root length, and reduced seedling root system. Metagenomics analysis showed that 10 key characteristic microorganisms, mainly , , and , were responsible for continuously planted trees. Quantitative analysis showed that the number of microorganisms in these three genera decreased significantly with the increase of continuous planting. Gene function analysis showed that continuous planting led to the weakening of the environmental information processing-signal transduction ability of soil characteristic microorganisms, and the decrease of trees against stress. Reduced capacity for metabolism, genetic information processing-replication and repair resulted in reduced microbial propagation and reduced microbial quantity in the rhizosphere soil of trees. Secondly, amino acid metabolism, carbohydrate metabolism, glycan biosynthesis and metabolism, lipid metabolism, metabolism of cofactors and vitamins were all significantly reduced, resulting in a decrease in the ability of the soil to synthesize and metabolize carbon and nitrogen. These reduced capacities further led to reduced soil microbial quantity, microbial carbon and nitrogen, microbial respiration intensity, reduced soil enzyme nutrient cycling and resistance-related enzyme activities, a significant reduction in available nutrient content of rhizosphere soils, a reduction in the ion exchange capacity, and an impediment to growth. This study provides an important basis for the management of continuously planted plantations.
PubMed: 38126014
DOI: 10.3389/fpls.2023.1324184 -
Environmental Science and Pollution... Nov 2023Brevibacillus laterosporus ZR-11, a bio-control strain, was innovatively inoculated at maturity stage of composting to clarify its effect on physicochemical parameters...
Inoculating exogenous bacterium Brevibacillus laterosporus ZR-11 at maturity stage accelerates composting maturation by regulating physicochemical parameters and indigenous bacterial community succession.
Brevibacillus laterosporus ZR-11, a bio-control strain, was innovatively inoculated at maturity stage of composting to clarify its effect on physicochemical parameters and indigenous bacterial community structure in compost pile. Results revealed that ZR-11 inoculum rapidly increased pile temperature to 52 ºC and raised germination index (GI) value to beyond 85% on day 3, thereby achieving higher pile temperature and GI in the inoculated group than the non-inoculated group almost along maturity stage, and also decreased C/N ratio of the inoculated group to below 20 by composting end (day 8). Also, ZR-11 succeeded in colonizing compost pile along maturity stage. These suggested that ZR-11 as inoculum at maturity stage could accelerate compost maturation and have a potential to participate in bio-fertilizer production. High-throughput sequencing indicated that bacterial community structure experienced substantial succession in the inoculated and non-inoculated groups, and Firmicutes, Proteobacteria, and Actinobacteria were the dominant phyla in the two groups during maturity stage, with their abundances higher in the inoculated group. Saccharomonospora and Ammoniibacillus abundance increased on day 3 while Actinomadura abundance increased on day 6 in the inoculated group. As verified statistically, pile temperature and pH were key factors closely linked to dominant genera abundance, where Saccharomonospora and Ammoniibacillus abundance were positively correlated to pile temperature, while Actinomadura abundance was positively correlated to pile pH. Thus, it was inferred that ZR-11 inoculum could improve parameters such as temperature and pH to modify dominant genera abundance, thus regulating indigenous bacterial community succession, which might in turn promote compost maturation.
Topics: Composting; Brevibacillus; Bacillus; Firmicutes; Actinomycetales; Soil; Manure
PubMed: 37796351
DOI: 10.1007/s11356-023-30091-w -
Sheng Wu Gong Cheng Xue Bao = Chinese... Aug 2023Polyhydroxyalkanoate depolymerase (PHAD) can be used for the degradation and recovery of polyhydroxyalkanoate (PHA). In order to develop a PHAD with good stability under...
Polyhydroxyalkanoate depolymerase (PHAD) can be used for the degradation and recovery of polyhydroxyalkanoate (PHA). In order to develop a PHAD with good stability under high temperature, PHAD from (TumPHAD) was heterelogously expressed in BL21(DE3). At the same time, a mutant A190C/V240C with enhanced stability was obtained rational design of disulfide bonds. Characterization of enzymatic properties showed that the mutant A190C/V240C had an optimum temperature of 60 ℃, which was 20 ℃ higher than that of the wild type. The half-life at 50 ℃ was 7 hours, at 50 ℃ which was 21 times longer than that of the wild type. The mutant A190C/V240C was used for the degradation of polyhydroxybutyrate (PHB), one of the typical PHA. At 50 ℃, the degradation rate of PHB being treated for 2 hours and 12 hours was 2.1 times and 3.8 times higher than that of the wild type, respectively. The TumPHAD mutant A190C/V240C obtained in this study shows tolerance to high temperature resistance, good thermal stability and strong PHB degradation ability, which may facilitate the degradation and recovery of PHB.
Topics: Thermomonospora; Actinomycetales; Escherichia coli; Polyhydroxyalkanoates
PubMed: 37622365
DOI: 10.13345/j.cjb.220996