ACS Sustainable Chemistry & Engineering
·
2023
·
IF 8.4
Zhihao Zhang,Jiayu Xue,Zewen Sun,Jiale Wang,Guochao Xu,Ye Ni
Hydrogen-borrowing redox-neutral cascade reactions are promising for the synthesis of lactones from the perspective of sustainable chemistry. In this study, a novel NADPH-dependent Baeyer–Villiger monooxygenase AjBVMO was identified from Acinetobacter johnsonii with a specific activity of 0.96 U·mg–1 in the oxidation of cyclohexanone into ε-caprolactone. To achieve cofactor matching, NADP+-dependent KpADHT215V and CgKR1 with high oxidative activities toward cyclohexanol and 1,6-hexanediol were constructed for developing “substrate-supplied” and “product-convergent” hydrogen-borrowing redox-neutral cascade reactions. The effects of buffer systems on the activities and spontaneous hydrolysis of ε-caprolactone and the ratios of ADHs and BVMO on the conversion rates were explored. In the “substrate-supplied” system employing KpADHT215V and AjBVMO, as high as 68.6 mM ε-caprolactone could be obtained from 100 mM cyclohexanol, with a maximum TOF of 7.2 min–1 and a TTN of 337. In the “product-convergent” system employing CgKR1 and AjBVMO, 115.1 mM ε-caprolactone was produced from 100 mM cyclohexanone, with a maximum TOF of 5.7 min–1 and a TTN of 757. The product-convergent system is more efficient than the substrate-supplied system. Moreover, these two redox-neutral cascade systems could also be applied in the synthesis of lactones with different chain lengths such as γ-butyrolactone and δ-valerolactone. This study established efficient redox-neutral cascade systems for the synthesis of lactones featuring a high atomic economy with only H2O as a byproduct.
研究领域:
生物化学
·
可持续化学
·
酶工程
✓ 已验证
产品关联
DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2020
·
IF 7.539
Yuan-Yuan Li,Qing Li,Peng-Qi Zhang,Cui-Luan Ma,Jian-He Xu,Yu-Cai He
In this study, tin-loaded sulfonated zeolite (Sn-zeolite) catalyst was synthesized for catalysis of raw corncob (75.0 g/L) to 103.0 mM furfural at 52.3% yield in water (pH 1.0) at 170 °C. This corncob-derived furfural was subsequently biotransformed with recombinant E. coli CG-19 cells coexpressing NADPH-dependent reductase and glucose dehydrogenase at 35 °C by supplementary of glucose (1.5 mol glucose/mol furfural), sodium dodecyl sulfate (0.50 mM) and NADP + (1.0 μmol NADP + /mmol furfural) in the aqueous catalytic media (pH 7.5). Both sodium dodecyl sulfate (0.50 mM) and Sn 4+ (1.0 mM) could promote reductase activity by 1.4-folds. Within 3 h, furfural was wholly catalyzed into furfuryl alcohol. By combining chemical catalysis with Sn-zeolite and biocatalysis with CG-19 cells in one-pot, an effective and sustainable process was established for tandemly catalyzing renewable biomass into furfuryl alcohol under environmentally-friendly way.
研究领域:
生物化学
·
催化化学
·
可再生资源转化
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOCHEMICAL ENGINEERING JOURNAL
·
2015
·
IF 2.467
Qin Xu,Wei-Yi Tao,He Huang,Shuang Li
An NADPH-dependent carbonyl reductase (YlCR2) from Yarrowia lipolytica was discovered by genome mining, overexpressed in Escherichia coli BL21 and purified to homogeneity. To efficiently synthesize ethyl ( S )-4-chloro-3-hydroxybutanoate (( S )-CHBE) (99%, e.e), the highly stereoselective bioreduction of ethyl 4-chloro-3-oxobutanoate (COBE) into ( S )-CHBE with the recombinant E. coli BL21/pETYlCR2 was successfully demonstrated in an n -butyl acetate-water biphasic system (1:1, v/v) with NADPH self-regeneration by substrate-coupled system using sorbitol or mannitol as co-substrate. The optimum reaction condition for the biotransformation of COBE in the biphasic system were 3000 mM COBE, (1.2 or 1.3 mmol/mmol COBE) mannitol or sorbitol, 0.2 mM or 0.4 mM NADP + , 0.12 or 0.14 g (wet weight)/ml cell dosage, pH 5.0, 30 °C; ( S )-CHBE with yield of 90% and e.e of 99% was obtained after 10 h reaction. Furthermore, 3000 mM COBE could also be completely biotransformed after 20 h without addition of expensive cofactor NADP + . Significantly, E. coli BL21/pETYlCR2 shows the high potential in the industrial production of ( S )-CHBE.
研究领域:
生物化学
·
合成生物学
·
酶工程
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Shuo Wang,Guochao Xu,Ye Ni
A novel carbonyl reductase from Hyphopichia burtoni ( Hb KR) was discovered by gene mining. Hb KR is a NADPH-dependent dual function enzyme with reduction and oxidation activity belonging to SDR superfamily. Hb KR strictly follows Prelog priority in the reduction of long-chain aliphatic keto acids/esters containing remote carbonyl groups, such as 4-oxodecanoic acid and 5-oxodecanoic acid, producing ( S )- γ -decalactone and ( S )- δ -decalactone in >99 % e.e. Tailor-made engineering of Hb KR was conducted to improve its catalytic efficiency . Variant F207A/F86M was obtained with specific activity of 8.37 U/mg toward 5-oxodecanoic acid, which was 9.7-fold of its parent. Employing F207A/F86M, 100 mM 5-oxodecanoic acid could be reduced into optically pure ( S )- δ -decalactone. Molecular docking analysis indicates that substitution of aromatic Phe with smaller residues renders sufficient space for accommodating substrates in a more stable conformation. This study offers an efficient biocatalyst for the biosynthesis of ( S )-lactones, and provides guidance for engineering carbonyl reductases toward structurally hindered substrates.
研究领域:
生物化学
·
生物技术
·
酶工程
·
有机化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL RESEARCH IN TOXICOLOGY
·
2019
·
IF 3.274
Xiucai Guo,Wei Li,Qingmei Li,Yan Chen,Guode Zhao,Ying Peng,Jiang Zheng
Tofacitinib (TFT) is an oral JAK inhibitor which has been approved for the treatment of moderately and severely active rheumatoid arthritis. TFT was found to show concentration-, time-, and NADPH-dependent inhibition of CYP3A4, and irreversibility of the inactivation was also observed. Incubation (40 min, 37 °C) of recombinant CYP3A4 with TFT at 200 μM resulted in >70% loss of CYP3A4 activity. Estimated kinact and KI were 0.037 min–1 and 93.2 μM, respectively. GSH and superoxide dismutase/catalase revealed minor or little protection against the CYP3A4 inactivation. Furthermore, ketoconazole attenuated TFT-mediated CYP3A4 inactivation. Epoxide and α-keto-aldehyde intermediates of TFT were trapped and characterized in microsomal incubations, respectively. The aldehyde intermediate is believed to be the key for the enzyme inactivation. Multiple P450 enzymes, including CYPs2C19, 3A4, 2D6, and 1A2, participated in the metabolism of TFT to the epoxide, while the formation of the aldehyde was mainly catalyzed by CYP3A4. In conclusion, TFT was proven to be a mechanism-based inactivator of CYP3A4.
研究领域:
药理学
·
药物代谢
·
酶学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
NEW PHYTOLOGIST
·
2023
·Vol. 240
·期 2
·676-693
·
IF 9.4
Daili Ji,Manfei Luo,Yinjie Guo,Qiuxin Li,Lingxi Kong,Haitao Ge,Qi Wang,Qiulai Song,Xiannan Zeng,Jinfang Ma,Yingchun Wang,Jörg Meurer,Wei Chi
Summary Reactive carbonyl species (RCS) derived from lipid peroxides can act as critical damage or signaling mediators downstream of reactive oxygen species by modifying target proteins. However, their biological effects and underlying mechanisms remain largely unknown in plants. Here, we have uncovered the mechanism by which the RCS 4-hydroxy-(E)-2-nonenal (HNE) participates in photosystem II (PSII) repair cycle of chloroplasts, a crucial process for maintaining PSII activity under high and changing light conditions. High Light Sensitive 1 (HLT1) is a potential NADPH-dependent reductase in chloroplasts. Deficiency of HLT1 had no impact on the growth of Arabidopsis plants under normal light conditions but increased sensitivity to high light, which resulted from a defective PSII repair cycle. In hlt1 plants, the accumulation of HNE-modified D1 subunit of PSII was observed, which did not affect D1 degradation but hampered the dimerization of repaired PSII monomers and reassembly of PSII supercomplexes on grana stacks. HLT1 is conserved in all photosynthetic organisms and has functions in overall growth and plant fitness in both Arabidopsis and rice under naturally challenging field conditions. Our work provides the mechanistic basis underlying RCS scavenging in light acclimation and suggests a potential strategy to improve plant productivity by manipulating RCS signaling in chloroplasts.
研究领域:
植物生物学
·
分子生物学
·
光合作用
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
·
2024
·Vol. 90
·期 8
·
IF 3.9
Yating Li,Tong Xu,Yanqin Tu,Tong Li,Yifeng Wei,Yan Zhou
Phloroglucinol (1,3,5-trihydroxybenzene) is a key intermediate in the degradation of polyphenols such as flavonoids and hydrolysable tannins and can be used by certain bacteria as a carbon and energy source for growth. The identification of enzymes that participate in the fermentation of phloroglucinol to acetate and butyrate in Clostridia was recently reported. In this study, we present the discovery and characterization of a novel metabolic pathway for phloroglucinol degradation in the bacterium Collinsella sp. zg1085, from marmot respiratory tract. In both the Clostridial and Collinsella pathways, phloroglucinol is first reduced to dihydrophoroglucinol by the NADPH-dependent phloroglucinol reductase (PGR), followed by ring opening to form (S)-3-hydroxy-5-oxohexanoate by a Mn2+-dependent dihydrophloroglucinol cyclohydrolase (DPGC). In the Collinsella pathway, (S)-3-hydroxy-5-oxohexanoate is then cleaved to form malonate semialdehyde and acetone by a newly identified aldolase (HOHA). Finally, a NADP+-dependent malonate-semialdehyde dehydrogenase converts malonate semialdehyde to CO2 and acetyl-CoA, an intermediate in carbon and energy metabolism. Recombinant expression of the Collinsella PGR, DPGC, and HOHA in E. coli enabled the conversion of phloroglucinol into acetone, providing support for the proposed pathway. Experiments with Olsenella profusa, another bacterium containing the gene cluster of interest, show that the PGR, DPGC, HOHA, and MSDH are induced by phloroglucinol. Our findings add to the variety of metabolic pathways for the degradation of phloroglucinol, a widely distributed phenolic compound, in the anaerobic microbiome.
研究领域:
微生物学
·
生物化学
·
代谢途径
·
酶学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）