The Experts below are selected from a list of 14043 Experts worldwide ranked by ideXlab platform
Zhanfeng Liu - One of the best experts on this subject based on the ideXlab platform.
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faster recovery of Soil biodiversity in native species mixture than in eucalyptus monoculture after 60 years afforestation in tropical degraded coastal terraces
Global Change Biology, 2021Co-Authors: Luhui Kuang, Jun Wang, Zhijian Mou, Faming Wang, Jing Zhang, Hans Lambers, Jordi Sardans, Josep Penuelas, Stefan Geisen, Zhanfeng LiuAbstract:Afforestation is an effective method to restore degraded land. Afforestation methods vary in their effects on ecosystem multifunctionality, but their effects on Soil biodiversity have been largely overlooked. Here, we mapped the biodiversity and functioning of multiple Soil Organism groups resulting from diverse afforestation methods in tropical coastal terraces. Sixty years after afforestation from bare land (BL), plant species richness and the abundance of plant litter (398 ± 85 g m-2 ) and plant biomass (179 ± 3.7 t ha-1 ) in native tree species mixtures (MF) were restored to the level of native forests (NF; 287 ± 21 g m-2 and 243.0 ± 33 t ha-1 , respectively), while Eucalyptus monoculture (EP) only successfully restored the litter mass (388 ± 43 g m-2 ) to the level of NF. Soil fertility in EP and MF was increased but remained lower than in NF. For example, Soil nitrogen and phosphorus concentrations in MF (1.2 ± 0.2 g kg-1 and 408 ± 49 mg kg-1 , respectively; p < 0.05) were lower than in NF (1.8 ± 0.2 g kg-1 and 523 ± 24 mg kg-1 , respectively; p < 0.05). Soil biodiversity, abundance (except for nematodes), and community composition in MF were similar or greater than those in NF. In contrast, restoration with EP only enhanced the diversity of microbes and mites to the level of NF, but not for other Soil biota. Together, afforestation with native species mixtures can end up restoring vegetation and most aspects of the taxonomic and functional biodiversity in Soil whereas monoculture using fast-growing non-native species cannot. Native species mixtures show a greater potential to reach completely similar levels of Soil biodiversity in local natural forests if they are received some more decades of afforestation. Multifunctionality of Soil biotic community should be considered to accelerate such processes in future restoration practices.
Yunxia Luan - One of the best experts on this subject based on the ideXlab platform.
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a multi generational risk assessment of cry1f on the non target Soil Organism folsomia candida collembola based on whole transcriptome profiling
PeerJ, 2019Co-Authors: Chengwang Huang, Wanjun Chen, Xin Ke, Yunhe Li, Yunxia LuanAbstract:: The Bacillus thuringiensis toxin Cry1F has been used to develop insect-resistant genetically engineered crops. There has been great interest in evaluating its potential risk to non-target Organisms (NTOs). However, the majority of previous risk assessments only examined one generation of NTOs using several physiological indicators, which cannot comprehensively detect some potential sub-lethal effects at the molecular level. In this study, we conducted a laboratory-based, multi-generational risk assessment of Cry1F for the collembolan Folsomia candida, an important representative of Soil arthropods in terms of survival, reproduction, and differentially expressed genes (DEGs) identified from whole transcriptome profiles. Our results demonstrated that Cry1F was continuously ingested by collembolans over three consecutive generations, but it did not affect the survival or reproduction of F. candida. There were no significant differences in the global gene expression between F. candida-fed diets with and without Cry1F, and no consistent co-expressed DEGs over three generations. In addition, Cry1F did not obviously alter the expression profiles of seven sensitive biological markers. Our composite data indicates that Cry1F had no long-term harmful effects on collembolan F. candida.
Jun Wang - One of the best experts on this subject based on the ideXlab platform.
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faster recovery of Soil biodiversity in native species mixture than in eucalyptus monoculture after 60 years afforestation in tropical degraded coastal terraces
Global Change Biology, 2021Co-Authors: Luhui Kuang, Jun Wang, Zhijian Mou, Faming Wang, Jing Zhang, Hans Lambers, Jordi Sardans, Josep Penuelas, Stefan Geisen, Zhanfeng LiuAbstract:Afforestation is an effective method to restore degraded land. Afforestation methods vary in their effects on ecosystem multifunctionality, but their effects on Soil biodiversity have been largely overlooked. Here, we mapped the biodiversity and functioning of multiple Soil Organism groups resulting from diverse afforestation methods in tropical coastal terraces. Sixty years after afforestation from bare land (BL), plant species richness and the abundance of plant litter (398 ± 85 g m-2 ) and plant biomass (179 ± 3.7 t ha-1 ) in native tree species mixtures (MF) were restored to the level of native forests (NF; 287 ± 21 g m-2 and 243.0 ± 33 t ha-1 , respectively), while Eucalyptus monoculture (EP) only successfully restored the litter mass (388 ± 43 g m-2 ) to the level of NF. Soil fertility in EP and MF was increased but remained lower than in NF. For example, Soil nitrogen and phosphorus concentrations in MF (1.2 ± 0.2 g kg-1 and 408 ± 49 mg kg-1 , respectively; p < 0.05) were lower than in NF (1.8 ± 0.2 g kg-1 and 523 ± 24 mg kg-1 , respectively; p < 0.05). Soil biodiversity, abundance (except for nematodes), and community composition in MF were similar or greater than those in NF. In contrast, restoration with EP only enhanced the diversity of microbes and mites to the level of NF, but not for other Soil biota. Together, afforestation with native species mixtures can end up restoring vegetation and most aspects of the taxonomic and functional biodiversity in Soil whereas monoculture using fast-growing non-native species cannot. Native species mixtures show a greater potential to reach completely similar levels of Soil biodiversity in local natural forests if they are received some more decades of afforestation. Multifunctionality of Soil biotic community should be considered to accelerate such processes in future restoration practices.
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dynamics of community structure and bio thermodynamic health of Soil Organisms following subtropical forest succession
Journal of Environmental Management, 2021Co-Authors: Jun Wang, Yongbiao Lin, Daniel E Campbell, Hongyue Cai, Hai RenAbstract:Abstract Soil Organisms play essential roles in maintaining multiple ecosystem processes, but our understanding of the dynamics of these communities during forest succession remains limited. In this study, the dynamics of Soil Organism communities were measured along a 3-step succession sequence of subtropical forests (i.e., a conifer forest, CF; a mixed conifer and broad-leaved forest, MF; and a monsoon evergreen broad-leaved forest, BF). The eco-exergy evaluation method was used as a complement to the classic community structure index system to reveal the holistic dynamics of the bio-thermodynamic health of Soil Organism communities in a forest succession series. Association between the self-organization of Soil Organisms, Soil properties, and plant factors were explored through redundancy analyses (RDA). The results indicated that the biomass of Soil microbes progressively increased in the dry season, from 0.75 g m−2 in CF to 1.75 g m−2 in BF. Microbial eco-exergy showed a similar pattern, while the community structure and the specific eco-exergy remained constant. Different trends for the seasons were observed for the Soil fauna community, where the community biomass increased from 0.72 g m−2 to over 1.97 g m−2 in the dry season, but decreased from 3.94 g m−2 to 2.36 g m−2 in the wet season. Faunal eco-exergies followed a similar pattern. Consequently, the average annual biomass of the Soil faunal community remained constant (2.17–2.39 g m−2) along the forest succession sequence, while the significant seasonal differences in both faunal biomass and eco-exergy observed at the early successional stage (CF) were insignificant in the middle and late forest successional stages (MF and BF). Both the dynamics of Soil microbes and Soil fauna were tightly correlated with tree biomass and with Soil physicochemical properties, especially Soil pH, moisture, total nitrogen, nitrate nitrogen, and organic matter content.
Paul Babitzke - One of the best experts on this subject based on the ideXlab platform.
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NusG-Dependent RNA Polymerase Pausing and Tylosin-Dependent Ribosome Stalling Are Required for Tylosin Resistance by Inducing 23S rRNA Methylation in Bacillus subtilis
mBio, 2019Co-Authors: Helen Yakhnin, Alexander V. Yakhnin, Brandon L. Mouery, Zachary F. Mandell, Catherine Karbasiafshar, Mikhail Kashlev, Paul BabitzkeAbstract:ABSTRACT Macrolide antibiotics bind to 23S rRNA within the peptide exit tunnel of the ribosome, causing the translating ribosome to stall when an appropriately positioned macrolide arrest motif is encountered in the nascent polypeptide. Tylosin is a macrolide antibiotic produced by Streptomyces fradiae. Resistance to tylosin in S. fradiae is conferred by methylation of 23S rRNA by TlrD and RlmAII. Here, we demonstrate that yxjB encodes RlmAII in Bacillus subtilis and that YxjB-specific methylation of 23S rRNA in the peptide exit tunnel confers tylosin resistance. Growth in the presence of subinhibitory concentrations of tylosin results in increased rRNA methylation and increased resistance. In the absence of tylosin, yxjB expression is repressed by transcription attenuation and translation attenuation mechanisms. Tylosin-dependent induction of yxjB expression relieves these two repression mechanisms. Induction requires tylosin-dependent ribosome stalling at an RYR arrest motif at the C terminus of a leader peptide encoded upstream of yxjB. Furthermore, NusG-dependent RNA polymerase pausing between the leader peptide and yxjB coding sequences is essential for tylosin-dependent induction. Pausing synchronizes the position of RNA polymerase with ribosome position such that the stalled ribosome prevents transcription termination and formation of an RNA structure that sequesters the yxjB ribosome binding site. On the basis of our results, we are renaming yxjB as tlrB. IMPORTANCE Antibiotic resistance is a growing health concern. Resistance mechanisms have evolved that provide bacteria with a growth advantage in their natural habitat such as the Soil. We determined that B. subtilis, a Gram-positive Soil Organism, has a mechanism of resistance to tylosin, a macrolide antibiotic commonly used in the meat industry. Tylosin induces expression of yxjB, which encodes an enzyme that methylates 23S rRNA. YxjB-dependent methylation of 23S rRNA confers tylosin resistance. NusG-dependent RNA polymerase pausing and tylosin-dependent ribosome stalling induce yxjB expression, and hence tylosin resistance, by preventing transcription termination upstream of the yxjB coding sequence and by preventing repression of yxjB translation.
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NusG-Dependent RNA Polymerase Pausing and Tylosin-Dependent Ribosome Stalling Are Required for Tylosin Resistance by Inducing 23S rRNA Methylation in Bacillus subtilis
'American Society for Microbiology', 2019Co-Authors: Helen Yakhnin, Alexander V. Yakhnin, Brandon L. Mouery, Zachary F. Mandell, Catherine Karbasiafshar, Mikhail Kashlev, Paul BabitzkeAbstract:Antibiotic resistance is a growing health concern. Resistance mechanisms have evolved that provide bacteria with a growth advantage in their natural habitat such as the Soil. We determined that B. subtilis, a Gram-positive Soil Organism, has a mechanism of resistance to tylosin, a macrolide antibiotic commonly used in the meat industry. Tylosin induces expression of yxjB, which encodes an enzyme that methylates 23S rRNA. YxjB-dependent methylation of 23S rRNA confers tylosin resistance. NusG-dependent RNA polymerase pausing and tylosin-dependent ribosome stalling induce yxjB expression, and hence tylosin resistance, by preventing transcription termination upstream of the yxjB coding sequence and by preventing repression of yxjB translation.Macrolide antibiotics bind to 23S rRNA within the peptide exit tunnel of the ribosome, causing the translating ribosome to stall when an appropriately positioned macrolide arrest motif is encountered in the nascent polypeptide. Tylosin is a macrolide antibiotic produced by Streptomyces fradiae. Resistance to tylosin in S. fradiae is conferred by methylation of 23S rRNA by TlrD and RlmAII. Here, we demonstrate that yxjB encodes RlmAII in Bacillus subtilis and that YxjB-specific methylation of 23S rRNA in the peptide exit tunnel confers tylosin resistance. Growth in the presence of subinhibitory concentrations of tylosin results in increased rRNA methylation and increased resistance. In the absence of tylosin, yxjB expression is repressed by transcription attenuation and translation attenuation mechanisms. Tylosin-dependent induction of yxjB expression relieves these two repression mechanisms. Induction requires tylosin-dependent ribosome stalling at an RYR arrest motif at the C terminus of a leader peptide encoded upstream of yxjB. Furthermore, NusG-dependent RNA polymerase pausing between the leader peptide and yxjB coding sequences is essential for tylosin-dependent induction. Pausing synchronizes the position of RNA polymerase with ribosome position such that the stalled ribosome prevents transcription termination and formation of an RNA structure that sequesters the yxjB ribosome binding site. On the basis of our results, we are renaming yxjB as tlrB
Luhui Kuang - One of the best experts on this subject based on the ideXlab platform.
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faster recovery of Soil biodiversity in native species mixture than in eucalyptus monoculture after 60 years afforestation in tropical degraded coastal terraces
Global Change Biology, 2021Co-Authors: Luhui Kuang, Jun Wang, Zhijian Mou, Faming Wang, Jing Zhang, Hans Lambers, Jordi Sardans, Josep Penuelas, Stefan Geisen, Zhanfeng LiuAbstract:Afforestation is an effective method to restore degraded land. Afforestation methods vary in their effects on ecosystem multifunctionality, but their effects on Soil biodiversity have been largely overlooked. Here, we mapped the biodiversity and functioning of multiple Soil Organism groups resulting from diverse afforestation methods in tropical coastal terraces. Sixty years after afforestation from bare land (BL), plant species richness and the abundance of plant litter (398 ± 85 g m-2 ) and plant biomass (179 ± 3.7 t ha-1 ) in native tree species mixtures (MF) were restored to the level of native forests (NF; 287 ± 21 g m-2 and 243.0 ± 33 t ha-1 , respectively), while Eucalyptus monoculture (EP) only successfully restored the litter mass (388 ± 43 g m-2 ) to the level of NF. Soil fertility in EP and MF was increased but remained lower than in NF. For example, Soil nitrogen and phosphorus concentrations in MF (1.2 ± 0.2 g kg-1 and 408 ± 49 mg kg-1 , respectively; p < 0.05) were lower than in NF (1.8 ± 0.2 g kg-1 and 523 ± 24 mg kg-1 , respectively; p < 0.05). Soil biodiversity, abundance (except for nematodes), and community composition in MF were similar or greater than those in NF. In contrast, restoration with EP only enhanced the diversity of microbes and mites to the level of NF, but not for other Soil biota. Together, afforestation with native species mixtures can end up restoring vegetation and most aspects of the taxonomic and functional biodiversity in Soil whereas monoculture using fast-growing non-native species cannot. Native species mixtures show a greater potential to reach completely similar levels of Soil biodiversity in local natural forests if they are received some more decades of afforestation. Multifunctionality of Soil biotic community should be considered to accelerate such processes in future restoration practices.