Natural plant-derived diterpenoids are a class of compounds with diverse structures and functions. These compounds are widely used in pharmaceuticals, cosmetics and food additives industries because of their pharmacological properties such as anticancer, anti-inflammatory and antibacterial activities. In recent years, with the gradual discovery of functional genes in the biosynthetic pathway of plant-derived diterpenoids and the development of synthetic biotechnology, great efforts have been made to construct a variety of diterpenoid microbial cell factories through metabolic engineering and synthetic biology, resulting in gram-level production of many compounds. This article summarizes the construction of plant-derived diterpenoid microbial cell factories through synthetic biotechnology, followed by introducing the metabolic engineering strategies applied to improve plant-derived diterpenoids production, with the aim to provide a reference for the construction of high-yield plant-derived diterpenoid microbial cell factories and the industrial production of diterpenoids.
Diterpenes/metabolism* ; Biotechnology ; Metabolic Engineering ; Biosynthetic Pathways/genetics* ; Plants/genetics* ; Synthetic Biology

Objective To construct a Type 1 diabetes model in miniature pigs and explore postoperative care strategies for effectively prolonging the survival time of the model pigs. Methods Seven Banna miniature pigs were selected for pancreatectomy. Glucose, vitamins, and antibiotics were administered for 3-5 days after surgery to aid recovery. Blood glucose and urine glucose levels were measured twice a day in the morning and evening to adjust insulin supplementation accordingly. The model pigs were observed daily and records were kept, including orexis, psychosis, weakness, skin ulcer, and feces and urine. Body weight was measured weekly until the death of the model animals. Based on the model pigs' condition, glucose injection and Ringer's lactate solution were administered to supplement nutrition and correct electrolyte imbalances. Results All seven Banna miniature pigs showed typical symptoms of diabetes: random blood glucose levels higher than 11.1 mmol/L after pancreatectomy, far exceeding the average blood glucose level of 6.0 mmol/L in normal pigs; positive urine glucose; and progressive weight loss. These features indicated the successful construction of Type 1 diabetes model. Additionally, Type 1 diabetic pigs that survived more than 8 weeks showed progressive hair loss and skin ulceration. Euthanasia was performed on model pigs when they were unable to stand or even eat independently, and pathological examination and HE staining were conducted on tissues collected from affected organs such as the liver, kidneys, and skin. Pathological sections revealed liver congestion, massive glycogen accumulation, ballooning degeneration of hepatocytes, and progressive liver fibrosis, along with glomerular congestion, vacuolar degeneration in renal tubular epithelial cells, proteinuria, dermal congestion, thinning of vascular walls, and varying degrees of parakeratosis and dyskeratosis in the liver, kidneys, and skin tissues due to prolonged hyperglycemia. The average survival time of the constructed Banna miniature pig diabetes model was 44 d, with a maximum survival time of 121 d. Conclusion Type 1 diabetes model can be constructed successfully in Banna miniature pigs through pancreatectomy. With meticulous postoperative care, a long-term Type 1 diabetes model with significant complications can be achieved, providing a stable large-animal model for Type 1 diabetes treatment strategies.

Danshen, the dried roots and rhizomes of Salvia miltiorrhiza Bunge (S. miltiorrhiza), is widely used in the treatment of cardiovascular and cerebrovascular diseases. Tanshinones, the bioactive compounds from Danshen, exhibit a wide spectrum of pharmacological properties, suggesting their potential for future therapeutic applications. Tanshinone biosynthesis is a complex process involving at least six P450 enzymes that have been identified and characterized, most of which belong to the CYP76 and CYP71 families. In this study, CYP81C16, a member of the CYP71 clan, was identified in S. miltiorrhiza. An in vitro assay revealed that it could catalyze the hydroxylation of four para-quinone-type tanshinones, namely neocryptotanshinone, deoxyneocryptotanshinone, and danshenxinkuns A and B. SmCYP81C16 emerged as a potential broad-spectrum oxidase targeting the C-18 position of para-quinone-type tanshinones with an impressive relative conversion rate exceeding 90%. Kinetic evaluations andin vivo assays underscored its highest affinity towards neocryptotanshinone among the tested substrates. The overexpression of SmCYP81C16 promoted the accumulation of (iso)tanshinone in hairy root lines. The characterization of SmCYP81C16 in this study accentuates its potential as a pivotal tool in the biotechnological production of tanshinones, either through microbial or plant metabolic engineering.
Humans ; Salvia miltiorrhiza/metabolism* ; Biosynthetic Pathways ; Quinones/metabolism* ; Plant Roots/metabolism* ; Gene Expression Regulation, Plant