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Enhanced cobalamin biosynthesis in Ensifer adhaerens by regulation of key genes with gradient promoters

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Synthetic and Systems Biotechnology 2022年第3期7卷 941-948页

作者： Sha Xu Zhiqiang Xiao Shiqin Yu Weizhu Zeng Yongming Zhu Jingwen Zhou National Engineering Laboratory for Cereal Fermentation Technology Jiangnan University1800 Lihu RoadWuxiJiangsu214122China School of Biotechnology and Key Laboratory of Industrial Biotechnology Ministry of EducationJiangnan University1800 Lihu RoadWuxiJiangsu214122China Science Center for Future Foods Jiangnan University1800 Lihu RoadWuxiJiangsu214122China Jiangsu Provisional Research Center for Bioactive Product Processing Technology Jiangnan University1800 Lihu RoadWuxiJiangsu214122China Hunan Hongying Biotechnology Co.Ltd. 10 Hongying RoadJinshiHunan415400China

cobalamin is an essential human vitamin widely used in the pharmaceutical,food,and feed additive industries and currently produced by bacteria or *** adhaerens HY-1 is an industrial strain that also produces *** production outputs are poor and the specific synthesis pathways require *** this study,the whole genome sequence of *** HY-1 was generated and annotated,and genes associated with cobalamin biosynthesis were ***,three genes,CobSV,CobQ,and CobW were identified as the most efficient ones for enhancing cobalamin *** transcriptome sequencing of *** HY-1 cells at different growth stages,65 endogenous promoters with different gradient strengths were *** combined expression of different strength promoters and key genes,a high cobalamin-producing recombinant strain,‘hmm’(genotype:PmetH-CobSV-PibpA-CobQ-Pmdh-CobW),was *** production was 143.8 mg/L in shaking flasks,which was 41.0%higher than the original *** production was further enhanced to 171.2 mg/L using fed-batch ***,our data and novel approach provide important references for the analysis of cobalamin synthesis and other metabolites in complex metabolic pathways.

关键词： Ensifer adhaerens cobalamin Genome sequence Transcriptome sequence Promoter Overexpression Combinations

Effects of ionic impurities on crystallization of cobalamin

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Frontiers of Chemical Science and Engineering 2010年第1期4卷 70-74页

作者： Baoli SHAO Hui CHEN Shuang WANG Haijun WANG Shenmin XU School of Chemistry and Chemical Engineering Tianjin University of TechnologyTianjin 300384China School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China

In this paper,the influence of two typical ionic impurities(Na_(+)and Mg_(2+))is investigated with the focused beam reflectance measurement(FBRM)*** this system,the on-line FBRM is used as a tool for monitoring the crystallization process of cobalamin by measuring the chord length distribution of particles and the particle *** is noted that impurity Mg_(2+)has a more significant effect than Na_(2+)in crystal growth of the whole crystallization *** the microscopic observation of crystals,Mg_(2+)has an obvious effect on the crystal habit,while Na_(2+)has little *** addition,the crystal habit changes can be monitored by particle vision measurement(PVM).Understanding these effects is helpful to aid optimization and improve process control.

关键词： ionic impurities crystallization cobalamin FBRM PVM

Dodecylamine Derivative of Hydroxocobalamin Acts as a Potent Inhibitor of cobalamin-Dependent Methionine Synthase in Mammalian Cultured COS-7 Cells

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Food and Nutrition Sciences 2014年第14期5卷 1318-1325页

作者： Tomohiro Bito Mariko Yasui Toshio Iwaki Yukinori Yabuta Tsuyoshi Ichiyanagi Ryoichi Yamaji Yoshihisa Nakano Hiroshi Inui Fumio Watanabe Department of Clinical Nutrition Osaka Prefecture University Habikino Japan Division of Applied Biological Chemistry Graduate School of Life and Environmental Sciences Osaka Prefecture University Sakai Japan Division of Applied Biological Chemistry Graduate School of Life and Environmental Sciences Osaka Prefecture University Sakai Japan Department of Clinical Nutrition Osaka Prefecture University Habikino Japan Division of Applied Biological Chemistry Graduate School of Life and Environmental Sciences Osaka Prefecture University Sakai Japan Department of Life Science Osaka Women’s Junior College Fujiidera Japan Division of Applied Bioresources Chemistry The United Graduate School of Agricultural Sciences Tottori University Tottori Japan

We evaluated whether the dodecylamine derivative of hydroxocobalamin acts as a potent inhibitor of cobalamin-dependent enzymes in an African green monkey kidney cell, COS-7. When the dodecylamine derivative (1.0 μmol/L) did not show any cytotoxicity in the cultured cells, the derivative could not affect methylmalonyl-CoA mutase (holo-enzyme) activity, but significantly inhibit methionine synthase (holo-enzyme) activity in the cell homogenates of COS-7 grown in 1.0 μmol/L hydroxocobalamin-supplemented medium. An immunoblot analysis indicated that the dodecylamine derivative could not decrease the protein level of methionine synthase, but significantly inhibit the enzyme activity.

关键词： Dodecylamine Derivative cobalamin COS-7 Cell Enzyme Inhibitor Hydroxocobalamin

Preparation and spectroscopic properties of 2',5'-dideoxynucleosidylcobalamins

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Chinese Journal of Chemistry 1994年第1期12卷 33-42页

作者： YAN, Hong CHEN, Hui-Lan SUN, Hong-Zhe XIE, De-Ping TANG, Wen-XiaDepartment of Chemistry and State Key Laboratory of Coordination Chemistry, Nanjing University, Nanjing, Jiangsu 210008, China Department of Chemistry and State Key Laboratory of Coordination Chemistry Nanjing University Nanjing Jiangsu 210008 China

Two new coenzyme B12 analogues, 2',5'-dideoxycytidylcobalamin (2a) and 2',5'-dide-oxyuridinylcobalamin (2b), and two others, 2',5'-dideoxyadenosylcobalamin (2c), and 5'-deoxy-thymidylcobalamin (2d) were prepared by an improved method. All the four analogues were investigated by UV-vis and 2D 1H NMR spectroscopy. The comparisons and discussion about their spectroscopic properties were done.

关键词： Coenzyme B12 analogues cobalamin 2'-deoxynucleoside UV-vis spectra 2D 1H NMR.

Saporin Conjugated Monoclonal Antibody to the Transcobalamin Receptor TCblR/CD320 Is Effective in Targeting and Destroying Cancer Cells

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Journal of Cancer Therapy 2013年第6期4卷 1074-1081页

作者： Edward V. Quadros Yasumi Nakayama Jeffrey M. Sequeira Department of Medicine SUNY-Downstate Medical Center Brooklyn USA

cobalamin uptake into cells is mediated by the CD320 receptor for transcobalamin-bound cobalamin. Optimum receptor expression is associated with proliferating cells and therefore, in many cancers this receptor expression is up regulated. Delivering drugs or toxins via this receptor provides increased targeting to cancer cells while minimizing toxicity to the normal tissues. Saporin conjugated monoclonal antibodies to the extracellular domain of TCblR were effectively internalized to deliver a toxic dose of Saporin to some cancer cell lines propagating in culture. Antibody concentration of 2.5 nM was effective in producing optimum inhibition of cell proliferation. The cytotoxic effect of mAb-Saporin appears to be dictated primarily by the level of receptor expression and therefore normal primary cells expressing low levels of CD320 were spared while tumor cell lines with higher CD320 expression were destroyed. Targeting the pathway for cellular uptake of vitamin B12 via the CD320 receptor with toxin-antibody conjugates appears to be a viable treatment strategy for certain cancers that over expresses this receptor.

关键词： Transcobalamin Receptor CD320 Gene cobalamin Cancer Toxin

Association of comorbidities with increasing severity of peripheral neuropathy in diabetes mellitus

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World Journal of Diabetes 2013年第4期4卷 135-144页

作者： Shafna Sachedina Cory Toth School of Medicine Royal College of Surgeons IrelandCo. Department of Clinical Neurosciences the University of Calgary

AIM: To analyze a large population of patients with diabetes and peripheral neuropathy(PN) to determine other meaningful comorbid etiologies for ***: Peripheral Neuropathy is a common complication of type 1 and 2 diabetes mellitus;however,other potential causes for PN may be co-existing in patients with diabetes.A prospective cohort study was performed to assess patients with diabetes and *** compared patients having PN due solely to diabetes with patients possessing co-existing comorbidities,performing clinical(Toronto Clinical Scoring System and the Utah Early Neuropathy Scale),laboratory and electrophysiological assessments in all ***: Patients with either type 1 or 2 diabetes mellitus and co-existing comorbidities did not have more severe clinical or electrophysiological PN phenotypes ***,in patients with type 1 diabetes,presence of a lipid disorder was associated with greater PN *** type 2 diabetes patients,both a lipid disorder and cobalamin deficiency were associated with greater PN *** was no additive effect upon PN severity with presence of three or more comorbid ***: The presence of specific,and not general,comorbidities in patients with type 1 or 2 diabetes corresponds with greater PN severity.

关键词： Diabetic peripheral neuropathy Comorbidities Lipidemia cobalamin Methylmalonic acid

Determination of Vitamin B<sub>12</sub>in Chinese Black Tea Leaves

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Food and Nutrition Sciences 2014年第14期5卷 1326-1332页

作者： Fei Teng Tomohiro Bito Shigeo Takenaka Yukinori Yabuta Fumio Watanabe Department of Veterinary Science Graduate School of Life and Environmental Sciences Osaka Prefecture University Osaka Japan Division of Applied Bioresources Chemistry The United Graduate School of Agricultural Sciences Tottori University Tottori Japan

We determined vitamin B12 content of Chinese black tea leaves using a microbiological assay based on Lactobacillus delbrueckii ATCC 7830. Trace levels (0.25 - 0.69 μg/100g dry weight) of vitamin B12 were detected in Pu’er, Fu, and Brick tea leaves. However, vitamin B12 content (0.06 - 1.37 μg/100g dry weight) of Ryubao tea leaves significantly varied. To determine whether Chinese black tea leaves contain vitamin B12 or other corrinoid compounds that are inactive in humans, corrinoid compounds were purified from Ryubao tea by an immunoaffinity column chromatography and vitamin B12 was identified by liquid chromatography-electrospray ionization/tandem mass spectrometry. Vitamin B12 content in the tea drink prepared from Ryubao tea leaves was very low (0.8 ng/100mL). Our results indicate that Chinese black tea is usually not a good source of B12, although Ryubao tea leaves with the highest B12 content may be utilized as a source of this vitamin for vegerarians.

关键词： Chinese Black Tea Leaves cobalamin Ryubao Tea Vitamin B12

Vitamin B12 Screening in Cervical Spine Surgery Patients

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Neuroscience & Medicine 2011年第2期2卷 149-153页

作者： Abdullah Tolaymat Moataz Abbara M. Sami Walid Mohammed Ajjan Joe Sam Robinson Jr 不详

Introduction Vitamin B12 is very vital for the nervous system. Its deficiency can manifest with neurological symptoms like pain and paresthesias and in severe cases may cause not completely restorable neurological damage, especially in elderly patients. Methods The charts of 702 patients who underwent cervical spine surgery retrospectively reviewed and data collected . All patients were preoperatively seen by an internist who ordered Vit B12 levels for some of them. We used two thresholds for the diagnosis of vitamin B12 deficiency, 200 and 300 pg/mL as recommended by Yao et al. 1992. Data were also collected on gender, payor status, myelopathy, hemoglobin level, corpuscular parameters and glycosylated hemoglobin level (HbA1c). Vitamin B12 levels were compared between patients with HbA1c levels ≥ 6.1% and cobalamin deficiency by age and found an increase in cobalamin deficiency after 40 from 0% to 7.4% (200 threshold). Uninsured patients (25%) using the 200 pg/mL threshold and workers’ compensation (54.5%) and uninsured patients (50.0%) had the highest rate of Vit B12 deficiency using the 300 pg/mL threshold

关键词： Vitamin B12 cobalamin Cervical Spine Surgery