1.Cloning and expression of a beta-glucosidase gene umcel3G from metagenome of buffalo rumen and characterization of the translated product.
Hong GUO ; Yi FENG ; Xinchun MO ; Chengjie DUAN ; Jiliang TANG ; Jiaxun FENG
Chinese Journal of Biotechnology 2008;24(2):232-238
Metagenomic cosmid libraries containing 1.26 x 10(5) clones, covering about 4.8 x 10(6) kb metagenomic DNA of uncultured microorganisms from the contents of buffalo rumens were constructed, and 118 independent clones expressing beta-glucosidase activity were isolated from the libraries. Screening of these clones showed that eight clones expressed relatively higher beta-glucosidase activity at pH 5.0 and 37 degrees C. One out of the eight clones was subcloned. Sequencing analysis showed that an open reading frame (ORF) of 2223 bp, termed umcel3G, potentially encodes a beta-glucosidase. The encoded product shared highest homology with a beta-glucosidase from Bacillus sp. at 60% identity and 73% similarity. The umcel3G was over-expressed in Escherichia coli and the size of the translated product Umcel3G on SDS-PAGE was in agreement with the predicted molecular mass. Zymogram analysis showed that Umcel3G exhibited beta-glucosidase activity, confirming that this ORF encodes a beta-glucosidase. The Umcel3G, purified with Ni-NTA column, exhibited optimal activity at pH 6.0-6.5 and 45 degrees C. Certain ions such as Ca2+, Zn2+ had significant positive effect on the activity of Umcel3G. However, some ions such as Fe3+, Cu2+ gave significant inhibitory effect on the enzyme. The Ni-NTA purified recombinant beta-glucosidase Umcel3G had a specific activity of 22.8 IU/mg at pH4.5, 35 degrees C and at the presence of 5 mmol/L Ca2+, indicating that this enzyme has potential applications in the fermentative production of ethanol by simultaneous saccharification and cofermentation (SSCF) of lignocelluloses.
Animals
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Bacteria
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enzymology
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genetics
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Buffaloes
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Cloning, Molecular
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Escherichia coli
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genetics
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metabolism
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Open Reading Frames
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genetics
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Recombinant Proteins
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biosynthesis
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genetics
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isolation & purification
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metabolism
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Rumen
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microbiology
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beta-Glucosidase
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biosynthesis
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genetics
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isolation & purification
2.Latent profile analysis of fear of childbirth in late pregnancy women and its relationship with sense of coherence
Hailin LI ; Jing ZHANG ; Yaping FENG ; Jiaxun YANG ; Rui CHEN ; Yisha NI ; Xin LI
Chinese Journal of Modern Nursing 2024;30(33):4551-4557
Objective:To explore the latent classes of fear of childbirth in late pregnancy women and its relationship with sense of coherence, providing reference for precise support interventions in clinical practice.Methods:From January to September 2023, convenience sampling was used to select 304 pregnant women who underwent antenatal examination at the Obstetrics Clinic of Affiliated Hospital of Hangzhou Normal University as participants. The General Information Questionnaire, Childbirth Attitudes Questionnaire, and the Sense of Coherence Scale-13 (SOC-13) were used for questionnaire survey. Latent profile analysis was used to explore the categories of fear of childbirth in late pregnancy women, and analyzed differences of SOC-13 scores among women with different categories of fear of childbirth.Results:Fear of childbirth in 304 late pregnant women was divided into three latent classes, including low-level fear group of (50.0%, 152/304), moderate-level fear group of (35.2%, 107/304), and high-level fear group of (14.8%, 45/304). ANOVA analysis showed that there were statistically significant differences in total score and dimension scores of SOC-13 among late pregnancy women with three different classes of fear of childbirth ( P<0.05) . Conclusions:There are three latent classes of fear of childbirth in late pregnancy women. The sense of coherence among pregnant women affects their fear of childbirth. Nursing staff should address the heterogeneity of fear of childbirth in late pregnancy women, starting from sense of coherence, and take targeted intervention measures to reduce the fear of childbirth in late pregnancy women.