scholarly journals β-glucosidase genes differentially expressed during composting

2020 ◽  
Author(s):  
Xinyue Zhang ◽  
Xiehui Chen ◽  
Shanshan Li ◽  
Erlie Su ◽  
Jiawen Liu ◽  
...  
Keyword(s):  
Microbial Community ◽  
Cellulose Degradation ◽  
Degradation Mechanism ◽  
Microbial Community Composition ◽  
Global Scale ◽  
High Concentration ◽  
Down Regulation ◽  
Expression Of Genes ◽  
Glucose Tolerant ◽  
Functional Microbial Community

Abstract Background: Cellulose degradation by cellulase is brought about by complex communities of interacting microorganism, which significantly to the cycling of carbon on a global scale. β-Glucosidase is the rate-limiting enzyme of degradation of cellulose. Thus, analysis of expression of genes involved in cellulose degradation and regulation of β-glucosidase gene expression in composting is beneficial to a better understanding of cellulose degradation mechanism. According to our previous researches, we present the hypothesis that “microbial functional communities differentially regulate the expression of glucose-tolerant β-glucosidase and glucose sensitive β-glucosidase (up or down regulation) to adapt to the changes in cellulose degradation.” Results: Here, the functional microbial community structure and function change in association with cellulose degradation during the process of natural and inoculated composts was investigated by metatranscriptome and DNA clone library. Compared with inoculated compost, cellulose degradation was obviously inhibited during natural composting. Especially, the cooling phase of natural compost exhibited carbon catabolite repression (CCR) effect due to high concentration of glucose and cellobiose. The expression of genes encoding endoglucanase and exoglucanase were significantly down-regulation, while the CCR has no effect on β-glucosidase genes expression levels. But functional microbial community composition changed significantly, the composition of glucose-tolerant β-glucosidase increased. Conclusions: These results indicated that microbial functional communities differentially regulate the expression of glucose tolerant β-glucosidase (up regulation) and non-glucose tolerant β-glucosidase (down regulation) under CCR. This work provides a frame work to predict how functional microbial communities will respond to cellulose degradation conditions changes.

scholarly journals β-Glucosidase genes differentially expressed during composting

2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Xinyue Zhang ◽  
Bo Ma ◽  
Jiawen Liu ◽  
Xiehui Chen ◽  
Shanshan Li ◽  
...  
Keyword(s):  
Microbial Communities ◽  
Environmental Changes ◽  
Cellulose Degradation ◽  
Degradation Mechanism ◽  
Degradation Process ◽  
Global Scale ◽  
Expression Of Genes ◽  
Glucose Tolerant ◽  
Cooling Phase ◽  
And Function

Abstract Background Cellulose degradation by cellulase is brought about by complex communities of interacting microorganisms, which significantly contribute to the cycling of carbon on a global scale. β-Glucosidase (BGL) is the rate-limiting enzyme in the cellulose degradation process. Thus, analyzing the expression of genes involved in cellulose degradation and regulation of BGL gene expression during composting will improve the understanding of the cellulose degradation mechanism. Based on our previous research, we hypothesized that BGL-producing microbial communities differentially regulate the expression of glucose-tolerant BGL and non-glucose-tolerant BGL to adapt to the changes in cellulose degradation conditions. Results To confirm this hypothesis, the structure and function of functional microbial communities involved in cellulose degradation were investigated by metatranscriptomics and a DNA library search of the GH1 family of BGLs involved in natural and inoculated composting. Under normal conditions, the group of non-glucose-tolerant BGL genes exhibited higher sensitivity to regulation than the glucose-tolerant BGL genes, which was suppressed during the composting process. Compared with the expression of endoglucanase and exoglucanase, the functional microbial communities exhibited a different transcriptional regulation of BGL genes during the cooling phase of natural composting. BGL-producing microbial communities upregulated the expression of glucose-tolerant BGL under carbon catabolite repression due to the increased glucose concentration, whereas the expression of non-glucose-tolerant BGL was suppressed. Conclusion Our results support the hypothesis that the functional microbial communities use multiple strategies of varying effectiveness to regulate the expression of BGL genes to facilitate adaptation to environmental changes.

scholarly journals Mechanism of differential expression of β-glucosidase genes in functional microbial communities in response to carbon catabolite repression

2022 ◽  
Vol 15 (1) ◽  
Author(s):  
Xinyue Zhang ◽  
Xiehui Chen ◽  
Shanshan Li ◽  
Ayodeji Bello ◽  
Jiawen Liu ◽  
...  
Keyword(s):  
Microbial Community ◽  
Microbial Communities ◽  
Differential Expression ◽  
Carbon Metabolism ◽  
Catabolite Repression ◽  
Carbon Catabolite Repression ◽  
Regulatory Mechanism ◽  
Glucose Tolerant ◽  
And Function ◽  
Functional Microbial Community

Abstract Background β-Glucosidase is the rate-limiting enzyme of cellulose degradation. It has been stipulated and established that β-glucosidase-producing microbial communities differentially regulate the expression of glucose/non-glucose tolerant β-glucosidase genes. However, it is still unknown if this differential expression of functional microbial community happens accidentally or as a general regulatory mechanism, and of what biological significance it has. To investigate the composition and function of microbial communities and how they respond to different carbon metabolism pressures and the transcriptional regulation of functional genes, the different carbon metabolism pressure was constructed by setting up the static chamber during composting. Results The composition and function of functional microbial communities demonstrated different behaviors under the carbon metabolism pressure. Functional microbial community up-regulated glucose tolerant β-glucosidase genes expression to maintain the carbon metabolism rate by enhancing the transglycosylation activity of β-glucosidase to compensate for the decrease of hydrolysis activity under carbon catabolite repression (CCR). Micrococcales play a vital role in the resistance of functional microbial community under CCR. The transcription regulation of GH1 family β-glucosidase genes from Proteobacteria showed more obvious inhibition than other phyla under CCR. Conclusion Microbial functional communities differentially regulate the expression of glucose/non-glucose tolerant β-glucosidase genes under CCR, which is a general regulatory mechanism, not accidental. Furthermore, the differentially expressed β-glucosidase gene exhibited species characteristics at the phylogenetic level.

Microbial Community Composition During Artificial Frosting of Dried Persimmon Fruits

LWT ◽  
2021 ◽  
pp. 111694
Author(s):  
Xiaoxi Chen ◽  
Qin Chen ◽  
Yaxin Liu ◽  
Bin Liu ◽  
Xubo Zhao ◽  
...  
Keyword(s):  
Microbial Community ◽  
Community Composition ◽  
Microbial Community Composition

scholarly journals Benchmarking laboratory processes to characterise low-biomass respiratory microbiota

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Raiza Hasrat ◽  
Jolanda Kool ◽  
Wouter A. A. de Steenhuijsen Piters ◽  
Mei Ling J. N. Chu ◽  
Sjoerd Kuiling ◽  
...  
Keyword(s):  
Microbial Community ◽  
Community Composition ◽  
Microbial Community Composition ◽  
Positive Control ◽  
Rrna Gene ◽  
Elution Buffer ◽  
Community Profile ◽  
Microbial Community Profile ◽  
Microbial Dna ◽  
Pcr Conditions

AbstractThe low biomass of respiratory samples makes it difficult to accurately characterise the microbial community composition. PCR conditions and contaminating microbial DNA can alter the biological profile. The objective of this study was to benchmark the currently available laboratory protocols to accurately analyse the microbial community of low biomass samples. To study the effect of PCR conditions on the microbial community profile, we amplified the 16S rRNA gene of respiratory samples using various bacterial loads and different number of PCR cycles. Libraries were purified by gel electrophoresis or AMPure XP and sequenced by V2 or V3 MiSeq reagent kits by Illumina sequencing. The positive control was diluted in different solvents. PCR conditions had no significant influence on the microbial community profile of low biomass samples. Purification methods and MiSeq reagent kits provided nearly similar microbiota profiles (paired Bray–Curtis dissimilarity median: 0.03 and 0.05, respectively). While profiles of positive controls were significantly influenced by the type of dilution solvent, the theoretical profile of the Zymo mock was most accurately analysed when the Zymo mock was diluted in elution buffer (difference compared to the theoretical Zymo mock: 21.6% for elution buffer, 29.2% for Milli-Q, and 79.6% for DNA/RNA shield). Microbiota profiles of DNA blanks formed a distinct cluster compared to low biomass samples, demonstrating that low biomass samples can accurately be distinguished from DNA blanks. In summary, to accurately characterise the microbial community composition we recommend 1. amplification of the obtained microbial DNA with 30 PCR cycles, 2. purifying amplicon pools by two consecutive AMPure XP steps and 3. sequence the pooled amplicons by V3 MiSeq reagent kit. The benchmarked standardized laboratory workflow presented here ensures comparability of results within and between low biomass microbiome studies.

Sign in / Sign up

Export Citation Format

Share Document