10 results on '"Zhou, Wenjuan"'
Search Results
2. Case Report: Novel Mutation of F5 With Maternal Uniparental Disomy Causes Severe Congenital Factor V Deficiency
- Author
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Cheng, Lin, Li, Ying, Zhou, Wenjuan, and Bo, Tao
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Pediatrics, Perinatology and Child Health - Abstract
We summarized two cases of congenital factor V deficiency (FVD) associated with a novel F5 mutation, and analyzed the relationship of the clinical features and genetic characteristics in congenital FVD. Case 1 was a female newborn infant with remarkable bleeding who died of severe intracranial hemorrhage on day 42 after birth. She had significant prolongation of prothrombin time (PT) and activated partial thromboplastin time (APTT). The percentage activity of FV (PFV) was lower than 3% in case 1. The mother of case 1 showed no tendency to bleed. She had mild prolongation of PT and APTT. The PFV was only 43%. Both cases were found to have the same novel mutation in F5, which was c.5419G>A (p.Ala1807Thr) in exon 16. The variant in case 1 was inherited from the mother of case 1. Whole-exome sequencing (WES) also found a splice site mutation: a 103 Mb maternal uniparental disomy (UPD) of 1q21.1-qter in case 1, in which the F5 gene is located in this segment. So case 1 was homozygote and the mother of case 1 was heterozygote. The novel mutation of F5 was predicted to be harmful by bioinformatics software including Sorting Intolerant From Tolerant (SIFT), Polyphen2, LRT, and Mutation Taster. In summary, c.5419G>A (p.Ala1807Thr) in exon 16 of F5 is a pathogenic mutation, which causes severe congenital FVD in homozygote patients.
- Published
- 2022
3. Growth-coupled evolution of phosphoketolase to improve l-glutamate production by Corynebacterium glutamicum
- Author
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Dele-Osibanjo Taiwo Adeolu, Jibin Sun, Ping Zheng, Guo Xuan, Zhou Wenjuan, Qinggang Li, Jinhui Feng, Zhang Xiaoli, Jiao Liu, Xue Sun, Xiaowei Wang, and Yanhe Ma
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Mutant ,Phosphoketolase ,Glutamic Acid ,Applied Microbiology and Biotechnology ,Corynebacterium glutamicum ,03 medical and health sciences ,Enzyme kinetics ,Selection, Genetic ,Aldehyde-Lyases ,030304 developmental biology ,chemistry.chemical_classification ,0303 health sciences ,biology ,030306 microbiology ,Wild type ,Active site ,General Medicine ,Bifidobacterium adolescentis ,Recombinant Proteins ,Kinetics ,Enzyme ,chemistry ,Biochemistry ,Mutation ,Mutagenesis, Site-Directed ,biology.protein ,Specific activity ,Directed Molecular Evolution ,Biotechnology - Abstract
The introduction of the key non-oxidative glycolytic (NOG) pathway enzyme, phosphoketolases (PKTs), into heterologous hosts can improve the yield of a variety of acetyl CoA-derived products of interest. However, the low specific activity of existing PKTs compared with that of 6-phosphofructokinase (PFK), the key EMP pathway enzyme, largely limits their potential applications. To improve PKT activity, previous attempts have focused on increasing intracellular PKT concentration via the use of strong promoters. Herein, we report the establishment of a growth-coupled evolution strategy for the enrichment and selection of PKT mutants with improved specific activity in Corynebacterium glutamicum hosts with defective PFK. Five mutants from 9 Bifidobacterium adolescentis-source PKT (BA-PKT) mutant libraries were obtained. Site-directed mutagenesis analysis revealed 11 mutant sites which contributed to improved BA-PKT specific activity. Further structural analysis revealed that the mutant sites were located far away from the enzyme active site, which makes them almost unpredictable using a rational design approach. Mutant site recombination led to the construction of a novel mutant, PKTT2A/I6T/H260Y, with Vmax 29.77 ± 1.58 U/mg and Kcat/Km 0.32 ± 0.01 s−1/mM, which corresponds to 73.27 ± 3.25% and 80.16 ± 3.38% improvements, respectively, compared with the wildtype (Vmax; 17.17 ± 0.59 U/mg, Kcat/Km; 0.17 ± 0.01 s−1/mM). Expression of PKTT2A/I6T/H260 in C. glutamicum Z188 resulted in 16.67 ± 2.24% and 18.19 ± 0.53% improvement in l-glutamate titer and yield, respectively, compared with the wildtype BA-PKT. Our findings provide an efficient approach for improving the activity of PKTs. Furthermore, the novel mutants could serve as useful tools in improving the yield of l-glutamate and other acetyl CoA-associated products.
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- 2019
4. Additional file 1 of Predictors for HIV testing among Chinese workers in infrastructure construction enterprises in Kenya
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Zhou, Wenjuan, Deng, Wenyu, Luo, Junfei, Bai, Yin, He, Zeyi, and Wang, Honghong
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Data_FILES - Abstract
Additional file 1:.
- Published
- 2021
- Full Text
- View/download PDF
5. Isoleucyl-tRNA synthetase mutant based whole-cell biosensor for high-throughput selection of isoleucine overproducers
- Author
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Zhou Wenjuan, Yanmei Guo, Yu Wang, Jibin Sun, Qinggang Li, Ping Zheng, Xue Sun, Yanhe Ma, and Jiuzhou Chen
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Isoleucine-tRNA Ligase ,Mutant ,Biomedical Engineering ,Biophysics ,macromolecular substances ,02 engineering and technology ,Biosensing Techniques ,medicine.disease_cause ,01 natural sciences ,Amino Acyl-tRNA Synthetases ,chemistry.chemical_compound ,Sense (molecular biology) ,Electrochemistry ,medicine ,Amino Acids ,Isoleucine ,Escherichia coli ,chemistry.chemical_classification ,Aminoacyl tRNA synthetase ,010401 analytical chemistry ,technology, industry, and agriculture ,General Medicine ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Amino acid ,Kinetics ,chemistry ,Biochemistry ,0210 nano-technology ,Biosensor ,Intracellular ,Biotechnology - Abstract
Whole-cell amino acid biosensors can sense the concentrations of certain amino acids and output easily detectable signals, which are important for construction of microbial producers. However, many reported biosensors have poor specificity because they also sense non-target amino acids. Besides, biosensors for many amino acids are still unavailable. In this study, we proposed a new strategy for constructing whole-cell biosensors based on aminoacyl-tRNA synthetases (aaRSs), which take the advantage of their universality and intrinsically specific binding ability to corresponding amino acids. Taking isoleucine biosensor as an example, we first mutated the isoleucyl-tRNA synthetase in Escherichia coli to dramatically decrease its affinity to isoleucine. The engineered cells specifically sensed isoleucine and output isoleucine dose-dependent cell growth as an easily detectable signal. To further expand the sensing range, an isoleucine exporter was overexpressed to enhance excretion of intracellular isoleucine. Since cells equipped with the optimized whole-cell biosensor showed accelerated growth when cells produced higher concentrations of isoleucine, the biosensor was successfully applied in high-throughput selection of isoleucine overproducers from random mutation libraries. This work demonstrates the feasibility of engineering aaRSs to construct a new kind of whole-cell biosensors for amino acids. Considering all twenty proteinogenic and many non-canonical amino acids have their specific aaRSs, this strategy should be useful for developing biosensors for various amino acids.
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- 2020
6. Efficient bioproduction of 5-aminolevulinic acid, a promising biostimulant and nutrient, from renewable bioresources by engineered Corynebacterium glutamicum
- Author
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Yu Wang, Zhou Wenjuan, Yanhe Ma, Guo Xuan, Deming Rao, Jiuzhou Chen, Jibin Sun, and Ping Zheng
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5-Aminolevulinic acid ,0106 biological sciences ,Bioconversion ,lcsh:Biotechnology ,Management, Monitoring, Policy and Law ,01 natural sciences ,Applied Microbiology and Biotechnology ,lcsh:Fuel ,Hydrolysate ,Corynebacterium glutamicum ,Metabolic engineering ,03 medical and health sciences ,lcsh:TP315-360 ,lcsh:TP248.13-248.65 ,010608 biotechnology ,Cassava bagasse ,Bioreactor ,Food science ,030304 developmental biology ,0303 health sciences ,Renewable bioresource ,Renewable Energy, Sustainability and the Environment ,Chemistry ,Bioproduction ,General Energy ,Fermentation ,Bagasse ,Biotechnology - Abstract
Background 5-Aminolevulinic acid (5-ALA) is a promising biostimulant, feed nutrient, and photodynamic drug with wide applications in modern agriculture and therapy. Considering the complexity and low yield of chemical synthesis methods, bioproduction of 5-ALA has drawn intensive attention recently. However, the present bioproduction processes use refined glucose as the main carbon source and the production level still needs further enhancement. Results To lay a solid technological foundation for large-scale commercialized bioproduction of 5-ALA, an industrial workhorse Corynebacterium glutamicum was metabolically engineered for high-level 5-ALA biosynthesis from cheap renewable bioresources. After evaluation of 5-ALA synthetases from different sources, the 5-ALA biosynthetic pathway and anaplerotic pathway were rebalanced by regulating intracellular activities of 5-ALA synthetase and phosphoenolpyruvate carboxylase. The engineered biocatalyst produced 5.5 g/L 5-ALA in shake flasks and 16.3 g/L in 5-L bioreactors with a one-step fermentation process from glucose. To lower the cost of feedstock, cheap raw materials were used to replace glucose. Enzymatically hydrolyzed cassava bagasse was proven to be a perfect alternative to refined sugars since the final 5-ALA titer further increased to 18.5 g/L. Use of corn starch hydrolysate resulted in a similar 5-ALA production level (16.0 g/L) with glucose, whereas use of beet molasses caused seriously inhibition. The results obtained here represent a new record of 5-ALA bioproduction. It is estimated that replacing glucose with cassava bagasse will reduce the carbon source cost by 90.1%. Conclusions The high-level biosynthesis of 5-ALA from cheap bioresources will brighten the prospects for industrialization of this sustainable and environment-friendly process. The strategy for balancing metabolic flux developed in this study can also be used for improving the bioproduction of other value-added chemicals.
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- 2020
7. Enhancing thermostability and removing hemin inhibition of Rhodopseudomonas palustris 5-aminolevulinic acid synthase by computer-aided rational design
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Jibin Sun, Jiuzhou Chen, Jing Zhao, Deming Rao, Zhou Wenjuan, Zijian Tan, Ping Zheng, Yanhe Ma, and Ning Chen
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0106 biological sciences ,0301 basic medicine ,Hot Temperature ,Bioengineering ,01 natural sciences ,Applied Microbiology and Biotechnology ,Corynebacterium glutamicum ,03 medical and health sciences ,chemistry.chemical_compound ,Bacterial Proteins ,Sequence Analysis, Protein ,010608 biotechnology ,Enzyme Stability ,Fatty Acid Synthase, Type II ,Computer Simulation ,Thermostability ,biology ,Chemistry ,Rational design ,General Medicine ,biology.organism_classification ,Bioproduction ,Rhodopseudomonas ,030104 developmental biology ,Biochemistry ,Amino Acid Substitution ,Aminolevulinic acid synthase ,biology.protein ,Hemin ,Fermentation ,Rhodopseudomonas palustris ,Biotechnology - Abstract
To enhance the thermostability and deregulate the hemin inhibition of 5-aminolevulinic acid (ALA) synthase from Rhodopseudomonas palustris (RP-ALAS) by a computer-aided rational design strategy. Eighteen RP-ALAS single variants were rationally designed and screened by measuring their residual activities upon heating. Among them, H29R and H15K exhibited a 2.3 °C and 6.0 °C higher melting temperature than wild-type, respectively. A 6.7-fold and 10.3-fold increase in specific activity after 1 h incubation at 37 °C was obtained for H29R (2.0 U/mg) and H15K (3.1 U/mg) compared to wild-type (0.3 U/mg). Additionally, higher residual activities in the presence of hemin were obtained for H29R and H15K (e.g., 64% and 76% at 10 μM hemin vs. 27% for wild-type). The ALA titer was increased by 6% and 22% in fermentation using Corynebacterium glutamicum ATCC 13032 expressing H29R and H15K, respectively. H29R and H15K showed high thermostability, reduced hemin inhibition and slightly high activity, indicating that these two variants are good candidates for bioproduction of ALA.
- Published
- 2018
8. Developing a high-throughput screening method for threonine overproduction based on an artificial promoter
- Author
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Jibin Sun, Qinggang Li, Ping Zheng, Ya’nan Liu, Yongfei Liu, Zhidan Zhang, Yanhe Ma, Cunmin Sun, Tongcun Zhang, Zhou Wenjuan, Guoqiang Cao, Dawei Zhang, and Xiaowei Wang
- Subjects
Proteomics ,Threonine ,High-throughput screening ,Mutant ,Industrial fermentation ,Bioengineering ,Biology ,medicine.disease_cause ,Applied Microbiology and Biotechnology ,Bioreactors ,medicine ,Escherichia coli ,Overproduction ,Promoter Regions, Genetic ,chemistry.chemical_classification ,Research ,Flow Cytometry ,Molecular biology ,Amino acid ,High-Throughput Screening Assays ,Biochemistry ,chemistry ,Threonine production ,Threonine biosensor ,Genetic Engineering ,Biotechnology - Abstract
l-Threonine is an important amino acid for animal feed. Though the industrial fermentation technology of threonine achieved a very high level, there is still significant room to further improve the industrial strains. The biosensor-based high-throughput screening (HTS) technology has demonstrated its powerful applications. Unfortunately, for most of valuable fine chemicals such as threonine, a HTS system has not been established mainly due to the absence of a suitable biosensor. In this study, we developed a HTS method to gain high-yielding threonine-producing strains. Novel threonine sensing promoters including cysJp and cysHp were discovered by proteomic analyses of Escherichia coli in response to extracellular threonine challenges. The HTS method was constructed using a device composed of the fused cysJp and cysHp as a promoter and a linked enhanced green fluorescent protein gene as a reporter. More than 400 strains were selected with fluorescence activated cell sorting technology from a library of 20 million mutants and tested within 1 week. Thirty-four mutants have higher productivities than the starting industrial producer. One mutant produced 17.95 % more threonine in a 5-L jar fermenter. This method should play a functional role for continuous improvement of threonine industry. Additionally, the threonine sensor construction using promoters obtained by proteomics analyses is so convenient that it would be easily extended to develop HTS models for other biochemicals.
- Published
- 2015
9. Complete genome sequence of Corynebacterium glutamicum B253, a Chinese lysine-producing strain
- Author
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Zhou Wenjuan, Li Pengpeng, Ning Chen, Yong Wu, Ping Zheng, and Jibin Sun
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Genetics ,Comparative genomics ,Whole genome sequencing ,Circular bacterial chromosome ,Lysine ,Molecular Sequence Data ,Bioengineering ,General Medicine ,Sequence Analysis, DNA ,Biology ,Applied Microbiology and Biotechnology ,Genome ,Corynebacterium glutamicum ,Plasmid ,Mutation ,bacteria ,Gene ,Genome size ,Genome, Bacterial ,Biotechnology - Abstract
We disclosed the complete genome sequence of Corynebacterium glutamicum B253, an important lysine-producing strain in China. The genome consists a circular chromosome (3,159,203bp) and a plasmid (24,775bp), encoding 2767 protein coding genes in total. The genome contains all genes for lysine biosynthesis, and some mutations potentially relevant to lysine production were detected in comparison with sequence of other C. glutamicum.
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- 2015
10. Enhanced extracellular production of α-amylase in Bacillus subtilis by optimization of regulatory elements and over-expression of PrsA lipoprotein
- Author
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Zhou Wenjuan, Fu Gang, Jianping Wen, Jingqi Chen, Dawei Zhang, and Yuanming Gai
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Signal peptide ,Lipoproteins ,Heterologous ,Gene Expression ,Bioengineering ,Bacillus subtilis ,Biology ,Protein Sorting Signals ,Applied Microbiology and Biotechnology ,Metabolic engineering ,Bacterial Proteins ,Gene expression ,Extracellular ,Secretion ,Promoter Regions, Genetic ,Membrane Proteins ,Promoter ,General Medicine ,Gene Expression Regulation, Bacterial ,biology.organism_classification ,Recombinant Proteins ,Biochemistry ,Metabolic Engineering ,alpha-Amylases ,Biotechnology - Abstract
α-Amylase was used as a heterologous model protein to investigate the effects of promoters, signal peptides and over-expression of an extra-cytoplasmic molecular chaperone, PrsA lipoprotein, on enhancing the secretion of α-amylase in Bacillus subtilis. Four promoters and six signal peptides were compared, successively, and the highest yield of α-amylase was achieved under the promotion mediated by PAprE, a strong constitutive promoter, and secretion by SPnprE, a signal peptide from B. subtilis. Moreover, under conditions of overexpressed PrsA lipoprotein, the secretion production and activity of α-amylase increased to 2.5-fold. The performance of the recombinant B. subtilis 1A751PL31 was evaluated with a fed-batch fermentation in a 7.5 l fermentor. Optimization of regulatory elements and over-expression of PrsA lipoprotein had a significant effect on enhancing the production of α-amylase in B. subtilis.
- Published
- 2014
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