1.Cloning and application of a novel hydroxylase in lovastatin conversion.
Xiaoyu HUO ; Bin ZHUGE ; Huiying FANG ; Hong ZONG ; Jian SONG ; Jian ZHUGE
Chinese Journal of Biotechnology 2013;29(11):1590-1598
Wuxistatin, a novel and potent statin, is converted from lovastatin by Amycolatopsis sp. CGMCC1149. In the bioconversion, lovastatin is firstly hydroxylated by a hydroxylase. To obtain the critical hydroxylase, a novel hydroxylase gene was isolated from Amycolatopsis sp. CGMCC1149 by Degenerate PCR and Self-Formed Adaptor PCR and expressed in Escherichia coli. BLAST sequence analysis revealed that the gene belonged to cytochrome P450 gene superfamily and could encode a 403-amino-acid protein with a molecular weight of 44.8 kDa. The secondary structure prediction result showed that this protein contained many typical functional regions of P450, such as oxygen binding site, ion-pair region and heme binding region. Meanwhile, a catalytic function verification system was constructed by NADH, ferredoxin and ferredoxin reductase which could catalyze lovastatin hydroxylation into the target product. These would be helpful for further studies in large-scale production of wuxistatin.
Actinomycetales
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enzymology
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genetics
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Amino Acid Sequence
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Butyrates
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metabolism
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Cloning, Molecular
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Cytochrome P-450 Enzyme System
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genetics
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metabolism
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Hydroxylation
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Industrial Microbiology
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Lovastatin
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metabolism
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Molecular Sequence Data
2.Current LC-MS-based strategies for characterization and quantification of antibody-drug conjugates
Xiaoyu ZHU ; Shihan HUO ; Chao XUE ; Bo AN ; Jun QU
Journal of Pharmaceutical Analysis 2020;10(3):209-220
The past few years have witnessed enormous progresses in the development of antibody-drug conju-gates (ADCs). Consequently, comprehensive analysis of ADCs in biological systems is critical in sup-porting discovery, development and evaluation of these agents. Liquid chromatography-mass spectrometry (LC-MS) has emerged as a promising and versatile tool for ADC analysis across a wide range of scenarios, owing to its multiplexing ability, rapid method development, as well as the capability of analyzing a variety of targets ranging from small-molecule payloads to the intact protein with a high, molecular resolution. However, despite this tremendous potential, challenges persist due to the high complexity in both the ADC molecules and the related biological systems. This review summarizes the up-to-date LC-MS-based strategies in ADC analysis and discusses the challenges and opportunities in this rapidly-evolving field.
3.Effects, status and problems of liver transplantation in the treatment of portal hypertension
Feng HUO ; Jianxiong CHEN ; Yujian ZHENG ; Xiaoyu TAN
Chinese Journal of Digestive Surgery 2018;17(10):976-980
Liver transplantation is the only effective treatment for portal hypertension (PHT) and end-stage liver disease.However,great therapeutic needs are far from satisfaction due to extreme shortage of donated livers.Good timing and indicator selection for PHT liver transplantation,and appropriate management of complications before or during on the waiting list,can avoid unnecessary liver transplantation and decrease the mortality rate of patients on waiting list.There are some particularities and issues worthy of attention.Understanding these particularities and handling these issues properly are extremely important to increase the success rate of PHT liver transplantation,enhance the recovery after surgery,and decrease the operative mortality.
4.Attaching importance to mechanical perfusion of donor liver and promoting high-quality development of liver transplantation
Qing OUYANG ; Xiaoyu TAN ; Feng HUO
Organ Transplantation 2021;12(1):1-
With the increasing quantity of organ donors and the continual expansion of the definition of extended criteria donor (ECD) livers, the quality of donor liver has become a prominent issue affecting the high-quality development of liver transplantation, which is also the study focus in related fields. Resolving the shortage of organs to the maximal extent and promoting the high-quality development of organ transplantation lead the development direction of organ donation and transplantation in China. In recent years, the application of mechanical perfusion (MP) for the perfusion, preservation, evaluation and repair of donor liver has become a hot topic to improve the quality of liver transplantation within the international community. In this article, according to different conditions of the application of ECD livers in liver transplantation at home and abroad in combination with the research progress on MP in the international community and relevant research experience of our center, the feasibility of establishing an organ intensive care unit (ICU) with integrated organ protection techniques was discussed, aiming to promote the high-quality development of organ transplantation in China and further expand the technical connotation of the "Chinese model" of organ donation and transplantation.