Article
Chemistry, Multidisciplinary
Eve M. Carter, Esther Ambrose-Dempster, John M. Ward, Tom D. Sheppard, Helen C. Hailes
Summary: Mechanochemical reactions have emerged as a green synthetic method due to their rapidity and lower solvent usage compared to traditional approaches. This study describes the first mechanoenzymatic reactions using transaminases for amination of aldehydes and ketones, resulting in the production of amines with significantly less aqueous medium. The use of whole cells and shorter reaction times also led to high yields and stereoselectivities.
Article
Chemistry, Multidisciplinary
Laura Edit Barabas, Diana Maria Scrob, Andrea Varga, Lorand Kiss, Monica Ioana Tosa, Csaba Paizs
Summary: This study developed a bi-enzymatic transaminase cascade using Pseudomonas psychrotolerans (PpS-TA) and human carbonic anhydrase II (hCAII) for efficient conversion of various (+/-)-1-phenylethan-1-amines to enantiopure (R)-amines and (S)-1-phenylethan-1-ols. The reaction medium, HEPES-DMSO, and a DMSO content of 30% were found to be suitable, improving solubilization of substrates and allowing for complete reduction of acetophenone. The cellular cascade showed improved viability compared to soluble enzymes, allowing for gram-scale conversion of (+/-)-1-phenylethan-1-amine to enantiopure products in high yields.
REACTION CHEMISTRY & ENGINEERING
(2023)
Article
Chemistry, Applied
Jinhai Yu, Weilu Zong, Yingying Ding, Junzhong Liu, Lina Chen, Hongjuan Zhang, Qingcai Jiao
Summary: The study focused on investigating ten omega-transaminases for synthesizing eighteen aromatic amines with high conversion rates and yields. Furthermore, the immobilized Bm-STA/UiO-66-NH2 composites showed excellent enzyme loading, storage stability, and other beneficial properties for industrial applications.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Multidisciplinary
Senjie Ma, Yumeng Xi, Haoyu Fan, Sven Roediger, John F. Hartwig
Summary: Asymmetric alkene hydroamination reactions often have limited synthetic value due to the requirement of excess alkene, limited enantioselectivity, and low tolerance towards functional groups. In this study, an enantioselective and intermolecular hydroamination reaction of unactivated terminal alkenes was developed, which occurs with equimolar amounts of alkene and amine, shows high tolerance towards functional groups, and yields products with high enantioselectivity and turnover numbers.
Article
Chemistry, Multidisciplinary
Jun Zhang, Daohong Liao, Rongchang Chen, Fangfang Zhu, Yaqing Ma, Lei Gao, Ge Qu, Chengsen Cui, Zhoutong Sun, Xiaoguang Lei, Shu-Shan Gao
Summary: In this study, a concise strategy combining rational design and engineering techniques was developed to enhance the substrate scope and catalytic efficiency of imine reductases (IREDs). The variant M5 exhibited superior performance and broad substrate scope for the synthesis of diverse azacycloalkylamines. This study provides exciting opportunities in medicinal and process chemistry as well as synthetic biology.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Arnau Rue Casamajo, Yuqi Yu, Christian Schnepel, Charlotte Morrill, Rhys Barker, Colin W. Levy, James Finnigan, Victor Spelling, Kristina Westerlund, Mark Petchey, Robert J. Sheppard, Richard J. Lewis, Francesco Falcioni, Martin A. Hayes, Nicholas J. Turner
Summary: In this study, a biocatalytic process was developed to access a specific diastereomer of a chiral amine building block used in drug discovery. The engineered biocatalyst showed high efficiency in producing the target chiral molecule and has the potential for further process development.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Biochemistry & Molecular Biology
Chao Xiang, Yu-Fei Ao, Matthias Hoehne, Uwe T. Bornscheuer
Summary: Amine transaminases (ATAs) are efficient biocatalysts for the synthesis of chiral amines, but wild-type ATAs have low catalytic activity under physiological conditions. Researchers have developed a variant, E49Q, of ATA that shows higher catalytic activity at pH 7.5 compared to the wild-type enzyme. This variant has been successfully used for the asymmetric synthesis of (R)-1-phenylethylamine.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Chemistry, Physical
Fulong Li, Yan Du, Youxiang Liang, Yuwen Wei, Yukun Zheng, Huimin Yu
Summary: This study redesigned a trans-aminase enzyme to enhance its catalytic efficiency towards bulky N-heterocyclic compounds. A variant with significant activity enhancement was obtained by fine-tuning the substrate-binding pocket with a simplified amino acid alphabet. The most active variant exhibited 1064-fold greater catalytic efficiency and improved activity towards a series of cyclic and bulky heterocyclic ketones. It also showed successful gram-scale synthesis of a chiral N-heterocyclic amine.
Article
Chemistry, Multidisciplinary
Jade Dussart-Gautheret, Julie Yu, Krithika Ganesh, Gaikwad Rajendra, Fabrice Gallou, Bruce H. Lipshutz
Summary: This study describes the surfactant-enabled asymmetric ATA-catalyzed reductive aminations in water, which enhance the conversion levels and enable 1-pot chemoenzymatic catalysis. The modified conditions involving both biocatalysis and chemocatalysis are environmentally responsible, indicating the potential of using chemistry in water.
Article
Chemistry, Multidisciplinary
Donglei Wang, Ying-Bo Shao, Yunrong Chen, Xiao-Song Xue, Xiaoyu Yang
Summary: An efficient method for the asymmetric synthesis of planar-chiral macrocycles (paracyclophanes) has been developed using chiral phosphoric acid catalysis for enantioselective electrophilic aromatic aminations with azodicarboxylates. This method allows for the synthesis of a wide range of chiral macrocycles with varying ring sizes and functional groups, achieving high yields and enantioselectivities. The mechanism and origins of the stereoselectivities of these reactions were investigated through experimental studies and computational calculations. Preliminary utilization of the planar-chiral macrocycle as a chiral organocatalyst demonstrated the potential applications of these novel chiral skeletons.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Lin Yang, Kaiyue Zhang, Meng Xu, Youyu Xie, Xiangqi Meng, Hualei Wang, Dongzhi Wei
Summary: In this study, the catalytic efficiency of omega-Transaminases (omega-TAs) was improved through a computational enzyme design strategy, leading to enhanced synthesis of chiral amines.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Review
Chemistry, Physical
Jianqiao Liu, Weixi Kong, Jing Bai, Yongxing Li, Lele Dong, Liya Zhou, Yunting Liu, Jing Gao, Ruth T. Bradshaw Allen, Nicholas J. Turner, Yanjun Jiang
Summary: This review discusses the importance and challenges of AmDHs in chiral-amine synthesis, as well as recent advances and engineering design strategies. By exploring the structures, mechanisms, and mutation studies of AmDHs, as well as the development of optimized reaction systems, guidance and direction are provided for improving the performance and efficiency of AmDHs.
Article
Chemistry, Multidisciplinary
Hua-Hua Wang, Hui Shao, Guanglong Huang, Jianqiang Fan, Wai-Pong To, Li Dang, Yungen Liu, Chi-Ming Che
Summary: In this study, chiral iron porphyrin complexes were found to catalyze the asymmetric intramolecular C(sp(3))-H amination of aryl and arylsulfonyl azides, providing chiral indolines and benzofused cyclic sulfonamides, respectively. The reactions exhibited high enantioselectivity (up to 93% ee) and high yields (up to 99%) under mild conditions with 410 nm light.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Applied
Feng Cheng, Jia-Min Zhang, Zhen-Tao Jiang, Xiao-Hu Wu, Ya-Ping Xue, Yu-Guo Zheng
Summary: Chiral amino acids have extensive applications in various industries. It has been shown that by gene mining and protein engineering, an NADH-dependent biocatalyst with high catalytic activity can be obtained, which allows the construction of an efficient and low-cost NAD(H)-driven biocatalytic system for the synthesis of chiral amino acids.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Multidisciplinary
Zhaofeng Gao, Jingwen Liu, Haizhou Huang, Huiling Geng, Mingxin Chang
Summary: The research reports on efforts to merge two asymmetric reductive amination reactions into a single-step transformation, utilizing specific catalyst and acid additives to successfully synthesize enantiopure secondary amine products.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Applied
Hong-Gon Kim, Sang-Woo Han, Jong-Shik Shin
ADVANCED SYNTHESIS & CATALYSIS
(2019)
Article
Biochemistry & Molecular Biology
Sang-Woo Han, Jong-Shik Shin
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
(2020)
Article
Biochemistry & Molecular Biology
Sung-Min Kang, Chenglong Jin, Do-Hee Kim, Sung Jean Park, Sang-Woo Han, Bong-Jin Lee
Summary: This study reveals a novel antimicrobial agent that activates HigB toxin to degrade mRNA as an antibacterial strategy against antibiotic-resistant Streptococcus pneumoniae, with a mechanism different from current antibiotics. Additionally, the structure of the HigBA complex and potential catalytic residues of HigB were identified, providing insights into the transcriptional regulation mechanisms and allosteric inhibition of HigB activity.
Article
Biochemistry & Molecular Biology
Sung-Min Kang, Heejo Moon, Sang-Woo Han, Hee Kim, Byeong Moon Kim, Bong-Jin Lee
ACS CHEMICAL BIOLOGY
(2020)
Article
Biotechnology & Applied Microbiology
Sang-Woo Han, Jong-Shik Shin
BIOCHEMICAL ENGINEERING JOURNAL
(2020)
Article
Biotechnology & Applied Microbiology
Yeri Choi, Sang-Woo Han, Jun-Sung Kim, Youngho Jang, Jong-Shik Shin
Summary: The study demonstrates that AADC-BA from Bacillus atrophaeus has a broad substrate specificity, allowing for efficient synthesis of various aromatic biogenic amines, including neurotransmitters. Experimental results show that AADC-BA can be used for the production of serotonin and other substances.
APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
(2021)
Article
Biotechnology & Applied Microbiology
Jung-Hun Kim, Yu-Ri Oh, Sang-Woo Han, Young-Ah Jang, Soon Ho Hong, Jung Hoon Ahn, Gyeong Tae Eom
Summary: By optimizing the culture medium composition and utilizing fed-batch fermentation, production of Sophorolipids from C. batistae was significantly increased, with successful separation and purification of the SLs achieved.
BIOPROCESS AND BIOSYSTEMS ENGINEERING
(2021)
Article
Chemistry, Physical
Sang-Woo Han, Ye-Ri Choi, Jong-Shik Shin
Summary: A novel biocatalytic process using AADC was developed for the preparative-scale production of biogenic amines, with broad substrate specificity and high conversion rates achieved under an ISPR strategy. The implementation of an open reactor system and cation exchange resin enabled efficient removal of reaction products, leading to high conversions within short reaction times.
Article
Microbiology
Sung-MM Kang, Heejo Moon, Sang-Woo Han, Byeong Wook Kim, Do-Hee Kim, Byeong Moon Kim, Bong-Jin Lee
Summary: Optimizing candidate peptides based on structural information from TA systems can lead to novel and effective antimicrobial agents targeting Mycobacterium tuberculosis, exhibiting enhanced activity and cell permeability. This approach opens a new era for developing TB therapies by utilizing structural and biochemical information for new antibiotic targets.
Article
Agriculture, Multidisciplinary
Hee Jeong Han, Yu-Ri Oh, Sang-Woo Han, Seung Soo Lee, Gyeong Tae Eom
Summary: This study successfully produced Lactobionic acid (LBA) using E. coli by coexpressing heterologous enzymes, without additional supplementation of cofactors. By optimizing culture conditions, the production titer and productivity of LBA were improved, providing a simple method for efficient LBA production in E. coli.
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
(2022)
Article
Biotechnology & Applied Microbiology
Sang-Woo Han, Yeri Choi, Youngho Jang, Jun-Sung Kim, Jong-Shik Shin
Summary: In this study, we employed an enzyme called aromatic L-amino acid decarboxylase (AADC) to achieve the kinetic resolution of diverse aromatic amino acids and successfully produce enantiopure D-amino acids and neuroactive monoamines. By using AADC from Bacillus atrophaeus, which has broad substrate specificity and excellent enantioselectivity, we achieved >99% enantiomeric excess for D-amino acid products. Furthermore, we developed an in situ product removal (ISPR) strategy to remove inhibitory monoamines, facilitating the kinetic resolution process.
BIOCHEMICAL ENGINEERING JOURNAL
(2022)
Review
Biotechnology & Applied Microbiology
Sang-Woo Han, Jong-Shik Shin
Summary: Aromatic L-amino acid decarboxylases (AADCs) catalyze the conversion of aromatic L-amino acids into aromatic monoamines. Microbial AADCs have limited distribution but hold significant potential for biomedical applications.
APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
(2022)
Review
Microbiology
Sang-Woo Han, Yasuo Yoshikuni
Summary: Plants benefit from symbiotic relationships with their microbiomes, but efforts to modify these microbiomes for enhanced plant growth and stress tolerance have had limited success. Synthetic biology, with its practical successes in other industries, could accelerate research in this area and hold promise for sustainable agriculture.
CURRENT OPINION IN MICROBIOLOGY
(2022)
Review
Biochemistry & Molecular Biology
Kaan Koper, Sang-Woo Han, Delia Casas Pastor, Yasuo Yoshikuni, Hiroshi A. Maeda
Summary: This review summarizes the evolutionary history, diverse metabolic roles, reaction mechanisms, and structure-function relationships of the Aminotransferases (ATs) enzyme family, with a special emphasis on their substrate promiscuity and multifunctionality.
JOURNAL OF BIOLOGICAL CHEMISTRY
(2022)
Article
Computer Science, Hardware & Architecture
Sangwoo Han, Minjung Cho, Gi Lee, Eui-Young Chung
Summary: Read disturb is a phenomenon where unselected wordlines in a block are affected while reading a selected wordline, causing errors. To address this, read reclaim operations migrate deteriorated block data to a new free block when a preset threshold is exceeded. However, these operations result in decreased performance and reliability. To mitigate this, we propose a Page Type-aware Data Migration technique (PTDM) that migrates pages within blocks based on their vulnerability to read disturb. Shifting from block-level to page-level read reclaim improves memory efficiency, and distributing read-hot data across multiple blocks reduces read disturb impact. Experimental results show a significant reduction in RR data migration and overall erasure counts using our proposed method.
IEEE TRANSACTIONS ON VERY LARGE SCALE INTEGRATION (VLSI) SYSTEMS
(2023)