Flavoprotein monooxygenases(FPMOs) and cytochrome P450(CYP450) oxygenases are pivotal monooxygenases in nature, catalyzing crucial redox reactions in diverse biological processes and contributing to the synthesis of highly complex natural products. While CYP450 enzymes have been extensively reported and studied, numerous FPMOs have also been discovered in past research endeavors, yet their classification, catalytic reactions, and catalytic mechanisms remain to be systematically analyzed. This paper comprehensively reviews the latest advancements in FPMOs research, initiating with a classification based on sequence similarities and distinct structural features. It delves into the catalytic characteristics of three subfamilies(FMO, BVMO, and NMO) within Class B FPMOs of plants, which are integral to biosynthetic pathways of natural products. Class B FPMOs encompass two canonical Rossmann fold motifs(FAD-binding GxGxxG and NADPH-binding GxGxxA), along with a central FMO recognition motif FxGxxxHxxxF/Y/W. These enzymes play a key role in regulating various metabolic routes and precisely modulate plant growth and development. Furthermore, the review summarizes the applications of Class B FPMOs of plants, showcasing through concrete examples their potential in synthesizing natural products such as auxins, indigo, and cyanogenic glycosides. These insights will broaden and deepen our understanding of FPMOs, fostering their transition from fundamental research to practical applications. More optimized biosynthetic pathways can be devised by leveraging FPMOs, conducive to the development of novel strategies and tools for agriculture, plant protection, natural product biosynthesis, and synthetic biology.
Biological Products/metabolism* ; Mixed Function Oxygenases/chemistry* ; Flavoproteins/chemistry* ; Plants/metabolism* ; Plant Proteins/chemistry* ; Cytochrome P-450 Enzyme System/genetics*

This study investigates the pharmacokinetics and metabolic characteristics of three marine-derived piericidins as potential drug leads for kidney disease: piericidin A (PA) and its two glycosides (GPAs), glucopiericidin A (GPA) and 13-hydroxyglucopiericidin A (13-OH-GPA). The research aims to facilitate lead selection and optimization for developing a viable preclinical candidate. Rapid absorption of PA and GPAs in mice was observed, characterized by short half-lives and low bioavailability. Glycosides and hydroxyl groups significantly enhanced the absorption rate (13-OH-GPA > GPA > PA). PA and GPAs exhibited metabolic instability in liver microsomes due to Cytochrome P450 enzymes (CYPs) and uridine diphosphoglucuronosyl transferases (UGTs). Glucuronidation emerged as the primary metabolic pathway, with UGT1A7, UGT1A8, UGT1A9, and UGT1A10 demonstrating high elimination rates (30%-70%) for PA and GPAs. This rapid glucuronidation may contribute to the low bioavailability of GPAs. Despite its low bioavailability (2.69%), 13-OH-GPA showed higher kidney distribution (19.8%) compared to PA (10.0%) and GPA (7.3%), suggesting enhanced biological efficacy in kidney diseases. Modifying the C-13 hydroxyl group appears to be a promising approach to improve bioavailability. In conclusion, this study provides valuable metabolic insights for the development and optimization of marine-derived piericidins as potential drug leads for kidney disease.
Animals ; Male ; Mice ; Aquatic Organisms/chemistry* ; Biological Availability ; Cytochrome P-450 Enzyme System/metabolism* ; Glucuronosyltransferase/metabolism* ; Microsomes, Liver/metabolism* ; Molecular Structure ; Biological Products/pharmacokinetics* ; Pyridines/pharmacokinetics*

Benzylisoquinoline alkaloids (BIAs) are a structurally diverse group of plant metabolites renowned for their pharmacological properties. However, sustainable sources for these compounds remain limited. Consequently, researchers are focusing on elucidating BIA biosynthetic pathways and genes to explore alternative sources using synthetic biology approaches. CYP80B, a family of cytochrome P450 (CYP450) enzymes, plays a crucial role in BIA biosynthesis. Previously reported CYP80Bs are known to catalyze the 3'-hydroxylation of (S)-N-methylcoclaurine, with the N-methyl group essential for catalytic activity. In this study, we successfully cloned a full-length CYP80B gene (StCYP80B) from Stephania tetrandra (S. tetrandra) and identified its function using a yeast heterologous expression system. Both in vivo yeast feeding and in vitro enzyme analysis demonstrated that StCYP80B could catalyze N-methylcoclaurine and coclaurine into their respective 3'-hydroxylated products. Notably, StCYP80B exhibited an expanded substrate selectivity compared to previously reported wild-type CYP80Bs, as it did not require an N-methyl group for hydroxylase activity. Furthermore, StCYP80B displayed a clear preference for the (S)-configuration. Co-expression of StCYP80B with the CYP450 reductases (CPRs, StCPR1, and StCPR2), also cloned from S. tetrandra, significantly enhanced the catalytic activity towards (S)-coclaurine. Site-directed mutagenesis of StCYP80B revealed that the residue H205 is crucial for coclaurine catalysis. Additionally, StCYP80B exhibited tissue-specific expression in plants. This study provides new genetic resources for the biosynthesis of BIAs and further elucidates their synthetic pathway in natural plant systems.
Cytochrome P-450 Enzyme System/chemistry* ; Benzylisoquinolines/chemistry* ; Hydroxylation ; Plant Proteins/chemistry* ; Alkaloids/metabolism* ; Stephania tetrandra/genetics*

Tripterifordin and neotripterifordin are important ent-kaurane diterpenoids in the Chinese medicinal herb Tripterygium wilfordii, possessing significant anti-HIV(human immunodeficiency virus) activity. On the basis of elucidating the natural biosynthetic pathways of these compounds, heterologous production with microbial cell factories can help to alleviate the reliance on plant resources and provide abundant raw materials for sustainable production. TwKO is the first CYP450 enzyme involved in the biosynthesis of tripterifordin and neotripterifordin. This study aimed to enhance the catalytic activity of TwKO by site-directed mutagenesis to benefit the production of tripterifordin and neotripterifordin in yeast. The AlphaFold DB established based on the AlphaFold 2 was employed to obtain the protein model of TwKO. According to multiple sequence alignments and principles of natural evolution, the key residues influencing the binding of TwKO to the substrate were identified. Subsequently, functional characterization of the mutants were conducted in Saccharomyces cerevisiae. A total of 71 mutants were obtained, among which 11 and 11 mutants had the abilities of enhancing the production of 16α-hydroxy-ent-kaurenol and 16α-hydroxy-ent-kaurenoic acid, respectively. In addition, 10 mutants could increase the proportion of the oxidation product of 16α-hydroxy-ent-kaurenol. In particular, R304 was identified as a key residue affecting the catalytic specificity of TwKO, the mutation of which led to the specific prodiction of 16α-hydroxy-ent-kaurenol. This study was the first to reveal the key residue affecting the catalytic activity of TwKO and obtained the mutants with increased TwKO activity, lay a foundation for the biosynthesis of tripterifordin and neotripterifordin.
Tripterygium/chemistry* ; Mutagenesis, Site-Directed ; Diterpenes, Kaurane/chemistry* ; Plant Proteins/chemistry* ; Cytochrome P-450 Enzyme System/chemistry* ; Saccharomyces cerevisiae/metabolism*

Insufficient catalytic efficiency of flavonoid 6-hydroxylases in the fermentative production of scutellarin leads to the formation of at least about 18% of by-products. Here, the catalytic mechanisms of two flavonoid 6-hydroxylases, CYP82D4 and CYP706X, were investigated by molecular dynamics simulations and quantum chemical calculations. Our results show that CYP82D4 and CYP706X have almost identical energy barriers at the rate-determining step and thus similar reaction rates, while the relatively low substrate binding energy of CYP82D4 may facilitate product release, which is directly responsible for its higher catalytic efficiency. Based on the study of substrate entry and release processes, the catalytic efficiency of the L540A mutation of CYP82D4 increased by 1.37-fold, demonstrating the feasibility of theoretical calculations-guided engineering of flavonoid 6-hydroxylase. Overall, this study reveals the catalytic mechanism of flavonoid 6-hydroxylases, which may facilitate the modification and optimization of flavonoid 6-hydroxylases for efficient fermentative production of scutellarin.
Cytochrome P-450 Enzyme System/metabolism* ; Apigenin ; Glucuronates

Gukang Capsules are often used in combination with drugs to treat fractures, osteoarthritis, and osteoporosis. Cytochrome P450(CYP450) mainly exists in the liver and participates in the oxidative metabolism of a variety of endogenous and exogenous substances and serves as an important cause of drug-metabolic interactions and adverse reactions. Therefore, it is of great significance to study the effect of Gukang Capsules on the activity and expression of CYP450 for increasing its clinical rational medication and improving the safety of drug combination. In this study, the Cocktail probe method was used to detect the changes in the activities of CYP1A2, CYP3A2, CYP2C11, CYP2C19, CYP2D4, and CYP2E1 in rat liver after treatment with high-, medium-and low-dose Gukang Capsules. The rat liver microsomes were extracted by the calcium chloride method, and protein expression of the above six CYP isoform enzymes was detected by Western blot. The results showed that the low-dose Gukang Capsules could induce CYP3A2 and CYP2D4 in rats, medium-dose Gukang Capsules had no effect on them, and high-dose Gukang Capsules could inhibit them in rats. The high-dose Gukang Capsules did not affect CYP2C11 in rats, but low-and medium-dose Gukang Capsules could induce CYP2C11 in rats. Gukang Capsules could inhibit CYP2C19 in rats and induce CYP1A2 in a dose-independent manner, but did not affect CYP2E1. If Gukang Capsules were co-administered with CYP1A2, CYP2C19, CYP3A2, CYP2C11, and CYP2D4 substrates, the dose should be adjusted to avoid drug interactions.
Rats ; Animals ; Cytochrome P-450 CYP1A2/metabolism* ; Cytochrome P-450 CYP2C19 ; Cytochrome P-450 CYP2E1/pharmacology* ; Rats, Sprague-Dawley ; Cytochrome P-450 Enzyme System/metabolism* ; Microsomes, Liver ; Liver ; Cytochrome P-450 CYP3A/metabolism*

Primary human hepatocytes (PHH) are the gold standard of in vitro human liver model for drug screening. However, a problem of culturing PHH in vitro is the rapid decline of cytochrome P450 (CYP450) activity, which plays an important role in drug metabolism. In this study, thermo-responsive culture dishes were used to explore the conditions for murine embryonic 3T3-J2 fibroblasts to form cell sheet. Based on the cell sheet engineering technology, a three-dimensional (3D) "sandwich" co-culture system of 3T3-J2 cell sheet/PHH/collagen gel was constructed. The tissue structure and protein expression of the model section were observed by hematoxylin eosin staining and immunofluorescence staining respectively. Phenacetin and bupropion were used as substrates to determine the activity of CYP450. The contents of albumin and urea in the system were determined by enzyme linked immunosorbent assay (ELISA). The results showed that the complete 3T3-J2 cell sheet could be obtained when the cell seeding density was 1.5×10⁶ /dish (35 mm dish) and the incubation time at low temperature was 60 min. Through cell sheet stacking, a 3D in vitro liver model was developed. Compared with the two-dimensional (2D) model, in the 3D model, the cell-cell and cell-matrix connections were tighter, the activities of cytochrome P450 CYP1A2 and cytochrome P450 CYP2B6 were significantly increased, and the secretion levels of albumin and urea were increased. These indexes could be maintained stably for 21 d. Therefore, cell sheet stacking is helpful to improve the level of liver function of 3D liver model. This model is expected to be used to predict the metabolism of low-clearance drugs in preclinical, which is of great significance for drug evaluation and other studies.
Albumins/metabolism* ; Animals ; Cytochrome P-450 Enzyme System/metabolism* ; Hepatocytes/metabolism* ; Humans ; Liver ; Mice ; Urea/metabolism*

Tripterygium hypoglaucum (Levl.) Hutch, a traditional Chinese medicinal herb with a long history of use, is widely distributed in China. One of its main active components, celastrol, has great potential to be developed into anti-cancer and anti-obesity drugs. Although it exhibits strong pharmacological activities, there is a lack of sustainable sources of celastrol and its derivatives, making it crucial to develop novel sources of these drugs through synthetic biology. The key step in the biosynthesis of celastrol is considered to be the cyclization of 2,3-oxidosqualene into friedelin under the catalysis of 2,3-oxidosqualene cyclases. Friedelin was speculated to be oxidized into celastrol by cytochrome P450 oxidases (CYP450s). Here, we reported a cytochrome P450 ThCYP712K1 from Tripterygium hypoglaucum (Levl.) Hutch that catalyzed the oxidation of friedelin into polpuonic acid when heterologously expressed in yeast. Through substrate supplementation and in vitro enzyme analysis, ThCYP712K1 was further proven to catalyze the oxidation of friedelin at the C-29 position to produce polpunonic acid, which is considered a vital step in the biosynthesis of celastrol, and will lay a foundation for further analysis of its biosynthetic pathway.
Anti-Obesity Agents ; Cytochrome P-450 Enzyme System/metabolism* ; Pentacyclic Triterpenes ; Squalene/analogs & derivatives* ; Tripterygium/metabolism* ; Triterpenes/metabolism*

OBJECTIVE: This study aimed to assess the associations between maternal drug use, cytochrome P450 ( CYP450) genetic polymorphisms, and their interactions with the risk of congenital heart defects (CHDs) in offspring. METHODS: A case-control study involving 569 mothers of CHD cases and 652 controls was conducted from November 2017 to January 2020. RESULTS: After adjusting for potential confounding factors, the results show that mothers who used ovulatory drugs (adjusted odds ratio [a OR] = 2.12; 95% confidence interval [ CI]: 1.08-4.16), antidepressants (a OR = 2.56; 95% CI: 1.36-4.82), antiabortifacients (a OR = 1.55; 95% CI: 1.00-2.40), or traditional Chinese drugs (a OR = 1.97; 95% CI: 1.26-3.09) during pregnancy were at a significantly higher risk of CHDs in offspring. Maternal CYP450 genetic polymorphisms at rs1065852 (A/T vs. A/A: OR = 1.53, 95% CI: 1.10-2.14; T/T vs. A/A: OR = 1.57, 95% CI: 1.07-2.31) and rs16947 (G/G vs. C/C: OR = 3.41, 95% CI: 1.82-6.39) were also significantly associated with the risk of CHDs in offspring. Additionally, significant interactions were observed between the CYP450genetic variants and drug use on the development of CHDs. CONCLUSIONS In those of Chinese descent, ovulatory drugs, antidepressants, antiabortifacients, and traditional Chinese medicines may be associated with the risk of CHDs in offspring. Maternal CYP450 genes may regulate the effects of maternal drug exposure on fetal heart development.
Adult ; Cytochrome P-450 Enzyme System/genetics* ; Female ; Genotype ; Heart Defects, Congenital/genetics* ; Humans ; Infant, Newborn ; Polymorphism, Genetic ; Pregnancy ; Pregnancy Complications/drug therapy*

Aconiti Kusnezoffii Radix Cocta is one of the most commonly used medicinal materials in Mongolian medicine. Due to the strong toxicity of Aconiti Kusnezoffii Radix Cocta, Mongolian medicine often uses Chebulae Fructus, Glycyrrhizae Radix et Rhizoma to reduce the toxicity, so as to ensure the curative effect of Aconiti Kusnezoffii Radix Cocta while ensuring its clinical curative effect, but the mechanism is not clear. The aim of this study was to investigate the effects of Chebulae Fructus, Glycyrrhizae Radix et Rhizoma and Aconiti Kusnezoffii Radix Cocta on the mRNA transcription and protein translation of cytochrome P450(CYP450) in the liver of normal rats. Male SD rats were randomly divided into negative control(NC) group, phenobarbital(PB) group(0.08 g·kg~(-1)·d~(-1)), Chebulae Fructus group(0.254 2 g·kg~(-1)·d~(-1)), Glycyrrhizae Radix et Rhizoma group(0.254 2 g·kg~(-1)·d~(-1)), Aconiti Kusnezoffii Radix Cocta group(0.254 2 g·kg~(-1)·d~(-1))and compatibility group(0.254 2 g·kg~(-1)·d~(-1),taking Aconiti Kusnezoffii Radix Cocta as the standard). After continuous administration for 8 days, the activities of total bile acid(TBA), alkaline phosphatase(ALP), amino-transferase(ALT) and aspartate aminotransferase(AST)in serum were detected, the pathological changes of liver tissue were observed, and the mRNA and protein expression levels of CYP1 A2, CYP2 C11 and CYP3 A1 were observed. Compared with the NC group, the serum ALP, ALT and AST activities in the Aconiti Kusnezoffii Radix Cocta group were significantly increased, and the ALP, ALT and AST activities were decreased after compatibility. At the same time, compatibility could reduce the liver injury caused by Aconiti Kusnezoffii Radix Cocta. The results showed that Aconiti Kusnezoffii Radix Cocta could inhibit the expression of CYP1 A2, CYP2 C11 and CYP3 A1, and could up-regulate the expression of CYP1 A2, CYP2 C11 and CYP3 A1 when combined with Chebulae Fructus and Glycyrrhizae Radix et Rhizoma. The level of translation was consistent with that of transcription. The compatibility of Chebulae Fructus and Glycyrrhizae Radix et Rhizoma with Aconiti Kusnezoffii Radix Cocta could up-regulate the expression of CYP450 enzyme, reduce the accumulation time of aconitine in vivo, and play a role in reducing toxicity, and this effect may start from gene transcription.
Animals ; Cytochrome P-450 Enzyme System/genetics* ; Drugs, Chinese Herbal ; Glycyrrhiza ; Liver ; Male ; Plant Extracts ; Rats ; Rats, Sprague-Dawley ; Terminalia