2.Biochemical properties of Scedosporium aurantiacum extracellular elastase-like protease.
Yuanhuai PENG ; Xin GE ; Jianzhi YE ; Bei JIN ; Zhiping HAN
Chinese Journal of Biotechnology 2023;39(9):3800-3813
Extracellular elastase-like protease is one of the key virulence proteases of Scedosporium aurantiacum. To date, little is known about this enzyme in terms of genetic information, structure, properties and virulence mechanism due to the difficulties in purification caused by its low secretion amount, high specific activity, uncompleted genome sequencing and annotation. This work investigated the gene, structure and enzymatic properties of this enzyme. The S. aurantiacum elastase-like protease from the fungal culture supernatant was analyzed through tandem mass spectrometry (MS/MS) approach, illustrating its primary structure. Bioinformatics tools were employed to predict the conserved domain and tertiary structure, the enzymatic properties were also studied. It turned out that S. aurantiacum extracellular elastase-like protease demonstrated well hydrolysis towards elastin and bovine achilles tendon collagen, with Vmax of 18.14 μg/s and 17.57 μg/s respectively, better than fish scale gelatin, with the lowest hydrolysis effect on casein. Its activity towards elastin was lower than that of the elastase from porcine pancreas, with values of Kcat/Km of 3.541 (μg/s) and 4.091 (μg/s), respectively. It was an alkaline protease, with optimal pH 8.2 and temperature 37 oC. Zn2+ promoted the enzymatic activity while Ca2+, Mg2+, Na+, elastatinal and PMSF inhibited its activity. Its sequence was similar to Paecilomyces lilacinus secreted serine protease (PDB Entry: c3f7oB_) with multiple conserved fractions each containing more than 7 amino acids, thus suitable for design of PCR primer. This study increased our knowledge on S. aurantiacum extracellular elastase-like protease in terms of structure and enzymatic properties, and may facilitate later studies on protein expression and virulence mechanism.
Animals
;
Cattle
;
Pancreatic Elastase/genetics*
;
Elastin/genetics*
;
Tandem Mass Spectrometry
;
Serine Proteases/genetics*
3.Production and antigenicity analysis of a recombinant insulinoma associated protein-2 in HEK293 cells.
Jingwen QIAN ; Pengbo WANG ; Yuanxing ZHANG ; Qin LIU
Chinese Journal of Biotechnology 2023;39(10):4246-4257
Insulinoma-associated protein-2 (IA-2) is a transmembrane glycoprotein belonging to the tyrosine phosphatase-like protein family as well as an important autoantigen in the diagnosis of type 1 diabetes. IA-2 products have been marketed in Europe and the United States. At present, commercially available IA-2 antigens are either the recombinant IA-2ic domain or the IA-2 naturally extracted from bovine islets. However, the recombinant IA-2 antigen displays weak positive in clinic practice, which often results in occasional detection failures, thus cannot completely replace the naturally extracted IA-2 antigen. In this study, an HEK293 expression system was used to explore the production of recombinant IA-2. An IA-2 transmembrane fragment (IA-2 TMF) located at amino acid position 449-979, also known as the natural membrane protein form of IA-2, was produced in HEK293 through transfection, and both the expression conditions and dissolution conditions of the membrane protein were also optimized. The purified membrane protein yield was 0.78 mg/L cell culture. Subsequently, the antigen activity of IA-2 TMF was compared with RSR rhIA-2 through enzyme linked immunosorbent assay. The serum of 77 type 1 diabetes patients and 32 healthy volunteers were detected. Receiver operating characteristic curve (ROC) curve was used to characterize the sensitivity and specificity of the test results. The results showed that the sensitivity of IA-2 TMF was 71.4% (55/77), while the sensitivity of RSR rhIA-2 was 63.6% (49/77), and the specificity of both antigens were all 100%. There was no significant difference in specificity between the two antigens, but the sensitivity of IA-2 TMF was appreciably better than that of the imported gold standard RSR rhIA-2 antigen. In conclusion, the recombinant IA-2 TMF produced in HEK293 cells can be used as a raw material to develop in vitro diagnostic reagents for type 1 diabetes.
Humans
;
Animals
;
Cattle
;
HEK293 Cells
;
Insulinoma
;
Diabetes Mellitus, Type 1/genetics*
;
Recombinant Proteins
;
Membrane Proteins
;
Pancreatic Neoplasms
4.Adaptation of the electron transport chain improves the biocatalytic efficiency of progesterone 17α hydroxylation.
Lanlan WANG ; Xin ZHAO ; Jie LI ; Jiaying AI ; Jing SUN ; Shuhong MAO
Chinese Journal of Biotechnology 2023;39(11):4608-4620
17α hydroxylase is a key enzyme for the conversion of progesterone to prepare various progestational drug intermediates. To improve the specific hydroxylation capability of this enzyme in steroid biocatalysis, the CYP260A1 derived from cellulose-mucilaginous bacteria Sorangium cellulosum Soce56 and the Fpr and bovine adrenal-derived Adx4-108 derived from Escherichia coli str. K-12 were used to construct a new electron transfer system for the conversion of progesterone. Selective mutation of CYP260A1 resulted in a mutant S276I with significantly enhanced 17α hydroxylase activity, and the yield of 17α-OH progesterone reached 58% after optimization of the catalytic system in vitro. In addition, the effect of phosphorylation of the ferredoxin Adx4-108 on 17α hydroxyl activity was evaluated using a targeted mutation technique, and the results showed that the mutation Adx4-108T69E transferred electrons to S276I more efficiently, which further enhanced the catalytic specificity in the C17 position of progesterone, and the yield of 17α-OH progesterone was eventually increased to 74%. This study provides a new option for the production of 17α-OH progesterone by specific transformation of bacterial-derived 17α hydroxylase, and lays a theoretical foundation for the industrial production of progesterone analogs using biotransformation method.
Animals
;
Cattle
;
Progesterone/metabolism*
;
Hydroxylation
;
Biocatalysis
;
Electron Transport
;
Mixed Function Oxygenases/metabolism*
5.Enzyme production mechanism of anaerobic fungus Orpinomyces sp. YF3 in yak rumen induced by different carbon source.
Xue'er DU ; Linlin ZHOU ; Fan ZHANG ; Yong LI ; Congcong ZHAO ; Lamei WANG ; Junhu YAO ; Yangchun CAO
Chinese Journal of Biotechnology 2023;39(12):4927-4938
In order to investigate the enzyme production mechanism of yak rumen-derived anaerobic fungus Orpinomyces sp. YF3 under the induction of different carbon sources, anaerobic culture tubes were used for in vitro fermentation. 8 g/L of glucose (Glu), filter paper (Flp) and avicel (Avi) were respectively added to 10 mL of basic culture medium as the sole carbon source. The activity of fiber-degrading enzyme and the concentration of volatile fatty acid in the fermentation liquid were detected, and the enzyme producing mechanism of Orpinomyces sp. YF3 was explored by transcriptomics. It was found that, in glucose-induced fermentation solution, the activities of carboxymethyl cellulase, microcrystalline cellulase, filter paper enzyme, xylanase and the proportion of acetate were significantly increased (P < 0.05), the proportion of propionate, butyrate, isobutyrate were significantly decreased (P < 0.05). The results of transcriptome analysis showed that there were 5 949 differentially expressed genes (DEGs) between the Glu group and the Flp group, 10 970 DEGs between the Glu group and the Avi group, and 6 057 DEGs between the Flp group and the Avi group. It was found that the DEGs associated with fiber degrading enzymes were significantly up-regulated in the Glu group. Gene ontology (GO) function enrichment analysis identified that DEGs were mainly associated with the xylan catabolic process, hemicellulose metabolic process, β-glucan metabolic process, cellulase activity, endo-1,4-β-xylanase activity, cell wall polysaccharide metabolic process, carbohydrate catabolic process, glucan catabolic process and carbohydrate metabolic process. Moreover, the differentially expressed pathways associated with fiber degrading enzymes enriched by Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were mainly starch and sucrose metabolic pathways and other glycan degradation pathways. In conclusion, Orpinomyces sp. YF3 with glucose as carbon source substrate significantly increased the activity of cellulose degrading enzyme and the proportion of acetate, decreased the proportion of propionate, butyrate and isobutyrate. Furthermore, the degradation ability and energy utilization efficiency of fungus in the presence of glucose were improved by means of regulating the expression of cellulose degrading enzyme gene and participating in starch and sucrose metabolism pathway, and other glycan degradation pathways, which provides a theoretical basis for the application of Orpinomyces sp. YF3 in practical production and facilitates the application of Orpinomyces sp. YF3 in the future.
Animals
;
Cattle
;
Neocallimastigales/metabolism*
;
Anaerobiosis
;
Rumen/microbiology*
;
Propionates/metabolism*
;
Isobutyrates/metabolism*
;
Cellulose/metabolism*
;
Fungi
;
Starch/metabolism*
;
Glucose/metabolism*
;
Acetates
;
Sucrose/metabolism*
;
Cellulases
;
Cellulase
6.Prokaryotic expression and biological activities of the hemolysin BL subunit of a pathogenic Bacillus cereus of cattle origin.
Yunjiao CHEN ; Yunjiang HE ; Qinglei MENG ; Zhilin LIU ; Xin ZHANG ; Zelin JIA ; Jiayu CUI ; Xueli WANG
Chinese Journal of Biotechnology 2023;39(12):4939-4949
Bacillus cereus belongs to Gram-positive bacteria, which is widely distributed in nature and shows certain pathogenicity. Different B. cereus strains carry different subsets of virulence factors, which directly determine the difference in their pathogenicity. It is therefore important to study the distribution of virulence factors and the biological activity of specific toxins for precise prevention and control of B. cereus infection. In this study, the hemolysin BL triayl was expressed, purified, and characterized. The results showed that the bovine pathogenic B. cereus hemolysin BL could be expressed and purified in the prokaryotic expression system, and the bovine pathogenic B. cereus hemolysin BL showed hemolysis, cytotoxicity, good immunogenicity and certain immune protection in mice. In this study, the recombinant expression of hemolysin BL triayl was achieved, and the biological activity of hemolysin BL of bovine pathogenic ceroid spore was investigated. This study may facilitate further investigating the pathogenic mechanism of B. cereus hemolysin BL and developing a detection method for bovine pathogenic B. cereus disease.
Cattle
;
Animals
;
Mice
;
Bacterial Proteins/metabolism*
;
Bacillus cereus/metabolism*
;
Hemolysin Proteins/metabolism*
;
Virulence Factors/metabolism*
;
Enterotoxins/metabolism*
7.Research progress on active ingredients of animal-derived traditional Chinese medicine in treatment of allergic rhinitis.
Xiang CHAO ; He LI ; Tie-Shan WANG ; Yan-Shu PAN
China Journal of Chinese Materia Medica 2023;48(18):4884-4892
Allergic rhinitis(AR) is a common chronic inflammatory disease of the upper respiratory tract. Due to its high prevalence, high recurrence rate, and lack of a definitive cure, it is considered a global health issue by the World Health Organization. The pathogenesis of AR is complex and mainly involves B cells, helper T cells, eosinophils, basophils, macrophages, as well as the cytokines and inflammatory mediators they secrete. Clinical treatment primarily focuses on inhibiting inflammatory mediators such as histamine and leukotrienes. In recent years, active ingredients of animal-derived traditional Chinese medicine(TCM) have shown unique advantages and potential in AR treatment thanks to their high safety, specificity, selectivity, and biopotency. This study systematically reviewed the therapeutic effects and mechanisms of active ingredients and mixed extracts from animal-derived TCM, such as bovine spleen, honeycomb, bee venom, maggot, and human placenta, which have been shown by modern pharmacological research to regulate the immune function in AR, providing a reference for further exploration and clinical development of active ingredients from animal-derived TCM. Studies have found that the active ingredients from animal-derived TCM can produce definite therapeutic effects in AR by modulating multiple immune balances in the body, with great clinical prospects. However, their mechanisms of action still require further investigation, and the quality control techniques for effective ingredients need to be improved. Currently, the research on active ingredients from animal-derived TCM in China has adopted an interactive system consisting of "traditional medical experience-based research, bioinformatics and artificial intelligence predictions, and validation and development through new experimental techniques". Based on this system, animal-derived TCM can combine modern scientific and technological means to maximize the therapeutic effects of active ingredients and serve the clinical application of AR in a more efficient and innovative manner.
Animals
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Cattle
;
Humans
;
Medicine, Chinese Traditional
;
Drugs, Chinese Herbal/therapeutic use*
;
Artificial Intelligence
;
Rhinitis, Allergic/drug therapy*
;
Porifera
;
Inflammation Mediators
8.Design and validation of a novel knee biomechanical test method.
Junrui WANG ; Zhiping ZHAO ; Chengteng JIANG ; Chuang NIE ; Quanxing SHI ; Meng LIU ; Jianwen GU
Journal of Biomedical Engineering 2023;40(6):1185-1191
A novel structural dynamics test method and device were designed to test the biomechanical effects of dynamic axial loading on knee cartilage and meniscus. Firstly, the maximum acceleration signal-to-noise ratio of the experimental device was calculated by applying axial dynamic load to the experimental device under unloaded condition with different force hammers. Then the experimental samples were divided into non-specimen group (no specimen loaded), sham specimen group (loaded with polypropylene samples) and bovine knee joint specimen group (loaded with bovine knee joint samples) for testing. The test results show that the experimental device and method can provide stable axial dynamic load, and the experimental results have good repeatability. The final results confirm that the dynamic characteristics of experimental samples can be distinguished effectively by this device. The experimental method proposed in this study provides a new way to further study the biomechanical mechanism of knee joint structural response under axial dynamic load.
Animals
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Cattle
;
Biomechanical Phenomena
;
Knee Joint/physiology*
;
Meniscus
;
Mechanical Phenomena
;
Weight-Bearing
9.Development of a flow cytometry method for detection of bovine multi-cytokines.
Zhaocheng ZHU ; Aihong XIA ; Zhaoli CAO ; Xin LI ; Xiang CHEN ; Zhengzhong XU ; Xin An JIAO
Chinese Journal of Biotechnology 2023;39(1):347-358
This study aims to develop a method to detect bovine multi-cytokines based on flow cytometry. Previously we have prepared and screened monoclonal antibodies against bovine cytokines IFN-γ, IL-2, TNF-α, IP-10 and MCP-1. These bovine cytokine monoclonal antibodies were fluorescently labeled, and the combination of antibody and cell surface molecules were used to develop the method for detecting bovine multi-cytokines. Subsequently, the developed method was used to determine the cytokine expression profile of Mycobacterium bovis BCG infected bovine peripheral blood mononuclear cells in vitro, and evaluate the cytokine expression level of peripheral blood CD4+ T cells of tuberculosis-positive cattle. The bovine multi-cytokine flow cytometry detection method can effectively determine the cytokine expression of BCG-infected bovine peripheral blood T lymphocytes. Among them, the expression levels of IFN-γ, IL-2, and TNF-α continue to increase after 40 hours of infection, while the expression levels of IP-10 and MCP-1 decreased. The combined detection of IFN-γ, IL-2, and TNF-α on CD4+ T lymphocytes in peripheral blood of cattle can effectively distinguish tuberculosis-positive and tuberculosis-negative samples. This method may facilitate evaluating the level of cellular immune response after bovine pathogen infection and vaccine injection.
Cattle
;
Animals
;
Cytokines
;
BCG Vaccine/metabolism*
;
Tumor Necrosis Factor-alpha/metabolism*
;
Interleukin-2
;
Flow Cytometry/methods*
;
Chemokine CXCL10/metabolism*
;
Leukocytes, Mononuclear
;
CD4-Positive T-Lymphocytes/metabolism*
;
Tuberculosis
;
Antibodies, Monoclonal/metabolism*
10.Intake of allergenic foods at 1.5 years and 3 years of age in a general child population in Japan: a cross-sectional study.
Takafumi TAKASE ; Mizuho NAGAO ; Rei KANAI ; Takahiro NISHIDA ; Tomoyuki ARIMA ; Fumiko IWAI ; Shingo YAMADA ; Makiko NAKAMOTO ; Masahiro HIRAYAMA ; Takao FUJISAWA
Environmental Health and Preventive Medicine 2023;28():6-6
BACKGROUND:
Recent studies indicate that the timing of introduction of potentially allergenic food is crucial for the development of food allergy in children. This cross-sectional study aimed to clarify the reality of allergen food intake in a general population of young children in Japan.
METHODS:
A questionnaire survey of caregivers was conducted at health checkups for 1.5-year (18-month)-old and 3-year-old children in the fall of 2020. The caregivers were asked about (1) the presence/absence of allergic disease symptoms based on the ISAAC questionnaire, and (2) foods that caregivers avoided giving their children. Ordinal logistic regression analyses were periformed to determine factors associated with food avoidance.
RESULTS:
Questionnaires were distributed to 1720 caregivers, and 1603 (93%) responded. The responders consisted of 771 and 832 caregivers who participated in 1.5-year-old and 3-year-old checkups, respectively. The prevalence of allergic diseases was comparable to recent epidemiological studies in Japan, indicating that the population may be representative. At 1.5 years old, more than 50% of the children were not exposed to peanuts, tree nuts, fish eggs, shellfish, and buckwheat. At 3 years old, the avoidance rates of the foods had decreased but were still between 18.8% and 32.0%. On the other hand, the avoidance rates of chicken egg and cow's milk, the top 2 common allergenic foods in Japan, were much lower at 2.8% and 1.5% at 1.5 years, and they decreased to 1.4% and 0.7% at 3 years old, respectively. Ordinal logistic analysis showed that avoidance of chicken egg, cow's milk, and wheat was associated with food allergy diagnosis and chicken egg avoidance with eczema, but avoidance of other foods showed no associations with any risk factors for food allergy.
CONCLUSION
Caregivers avoided giving various foods, independent of allergy risk factors, to their young children. Since delayed introduction of an allergenic food has been reported to increase the risk of developing an allergy to the food, the results warrant future investigation of the development of food allergies in relation to current eating habits and recommendations.
Female
;
Animals
;
Cattle
;
Humans
;
Cross-Sectional Studies
;
Japan/epidemiology*
;
Food Hypersensitivity/complications*
;
Risk Factors
;
Food
;
Allergens

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