Construction of cell factories for production of valencene in Saccharomyces cerevisiae / 药学学报

Valencene, a kind of sesquiterpenoid with a citrus flavor, is mainly found in Valencia orange and is commonly used in cosmetics and food additives, as well as industrial synthetic nootkatone. In this study, synthetic biology was used to create a Saccharomyces cerevisiae cell factory to produce valencene. Fistly, valencene synthase gene (CnVS) from Callitropsis nootkatensis was inserted into the chromosome of the chassis strain YTT-T5. The resulting strain VAL-01 could produce 1.1 mg·L-1 valencene. Protein fusion technique was used, different valencene synthases were compared and the copy number of key genes was adjusted, yielding valencene to 436.4 mg·L-1. Then, knocking-out the transcription factor ROX1 resulted in valencene improvement by 17.4%. Moreover, the induction system of galactose was regulated, transcription factor PDR3 and INO2 were overexpressed. The engineered strain VAL-10 could produce 2 798.6 mg·L-1 valencene by high cell density fermentation method (nearly 2 500 times higher than VAL-01). This study provides a basis for green production of valencene.

Construction of cell factories for production of patchoulol in Saccharomyces cerevisiae / 中国中药杂志

Patchoulol is an important sesquiterpenoid in the volatile oil of Pogostemon cablin, and is also considered to be the main contributing component to the pharmacological efficacy and fragrance of P. cablin oil, which has antibacterial, antitumor, antioxidant, and other biological activities. Currently, patchoulol and its essential oil blends are in high demand worldwide, but the traditional plant extraction method has many problems such as wasting land and polluting the environment. Therefore, there is an urgent need for a new method to produce patchoulol efficiently and at low cost. To broaden the production method of patchouli and achieve the heterologous production of patchoulol in Saccharomyces cerevisiae, the patchoulol synthase(PS) gene from P. cablin was codon optimized and placed under the inducible strong promoter GAL1 to transfer into the yeast platform strain YTT-T5, thereby obtaining strain PS00 with the production of(4.0±0.3) mg·L~(-1) patchoulol. To improve the conversion rate, this study used protein fusion method to fuse SmFPS gene from Salvia miltiorrhiza with PS gene, leading to increase the yield of patchoulol to(100.9±7.4) mg·L~(-1) by 25-folds. By further optimizing the copy number of the fusion gene, the yield of patchoulol was increased by 90% to(191.1±32.7) mg·L~(-1). By optimizing the fermentation process, the strain was able to achieve a patchouli yield of 2.1 g·L~(-1) in a high-density fermentation system, which was the highest yield so far. This study provides an important basis for the green production of patchoulol.

Construction of cell factories for high production of ginsenoside Rh_2 in Saccharomyces cerevisiae / 中国中药杂志

Ginsenoside Rh_2 is a rare active ingredient in precious Chinese medicinal materials such as Ginseng Radix et Rhizoma, Notoginseng Radix et Rhizoma, and Panacis Quinquefolii Radix. It has important pharmacological activities such as anti-cancer and improving human immunity. However, due to the extremely low content of ginsenoside Rh_2 in the source plants, the traditional way of obtaining it has limitations. This study intended to apply synthetic biological technology to develop a cell factory of Saccharomyces cerevisiae to produce Rh_2 by low-cost fermentation. First, we used the high protopanaxadiol(PPD)-yielding strain LPTA as the chassis strain, and inserted the Panax notoginseng enzyme gene Pn1-31, together with yeast UDP-glucose supply module genes[phosphoglucose mutase 1(PGM1), α-phosphoglucose mutase(PGM2), and uridine diphosphate glucose pyrophosphorylase(UGP1)], into the EGH1 locus of yeast chromosome. The engineered strain LPTA-RH2 produced 17.10 mg·g~(-1) ginsenoside Rh_2. This strain had low yield of Rh_2 while accumulated much precursor PPD, which severely restricted the application of this strain. In order to further improve the production of ginsenoside Rh_2, we strengthened the UDP glucose supply module and ginsenoside Rh_2 synthesis module by engineered strain LPTA-RH2-T. The shaking flask yield of ginsenoside Rh_2 was increased to 36.26 mg·g~(-1), which accounted for 3.63% of the dry weight of yeast cells. Compared with those of the original strain LPTA-RH2, the final production and the conversion efficiency of Rh_2 increased by 112.11% and 65.14%, respectively. This study provides an important basis for further obtaining the industrial-grade cell factory for the production of ginsenoside Rh_2.

Dynamic control of ERG20 expression to improve production of monoterpenes by engineering Saccharomyces cerevisiae / 中国中药杂志

Monoterpenes are widely used in cosmetics, food, medicine, agriculture and other fields. With the development of synthetic biology, it is considered as a potential way to create microbial cell factories to produce monoterpenes. Engineering Saccharomyces cerevisiae to produce monoterpenes has been a research hotspot in synthetic biology. In S. cerevisiae, the production of geranyl pyrophosphate(GPP) and farnesyl pyrophosphate(FPP) is catalyzed by a bifunctional enzyme farnesyl pyrophosphate synthetase(encoded by ERG20 gene) which is inclined to synthesize FPP essential for yeast growth. Therefore, reasonable control of FPP synthesis is the basis for efficient monoterpene synthesis in yeast cell factories. In order to achieve dynamic control from GPP to FPP biosynthesis in S. cerevisiae, we obtained a novel chassis strain HP001-pERG1-ERG20 by replacing the ERG20 promoter of the chassis strain HP001 with the promoter of cyclosqualene cyclase(ERG1) gene. Further, we reconstructed the metabolic pathway by using GPP and neryl diphosphate(NPP), cis-GPP as substrates in HP001-pERG1-ERG20. The yield of GPP-derived linalool increased by 42.5% to 7.6 mg·L~(-1), and that of NPP-derived nerol increased by 1 436.4% to 8.3 mg·L~(-1). This study provides a basis for the production of monoterpenes by microbial fermentation.

Prescription Research and Clinical Application of Yiguanjian / 中国实验方剂学杂志

By systematically sorting out the ancient medical books and modern clinical literature of Yiguanjian， the historical evolution of this formula， including its source， composition， origin， processing， dosage， preparation and usage， functions and indications， evolution of prescription meaning， is textual so as to clarify the historical evolution and clinical application of Yiguanjian. On the basis of fully considering the actual demand of development of famous classical formula preparation and the usage habit of modern clinical practice， the feasible development suggestions were put forward. Yiguanjian is composed of six herbs， which is derived from Yifang Jiedu (《医方絜度》) . It is an ancient book of traditional Chinese medicine edited by QIAN Min-jie in Qing dynasty. The original medicinal plants and medicinal parts of the formula were basically the same as those recorded in the 2020 edition of Chinese Pharmacopoeia. The raw products should be selected for decoction pieces and processed according to the methods recorded in the 2020 edition of Chinese Pharmacopoeia. The reference dose of the medicine in this formula is set out in Yifang Jiedu. According to dosage of one Qian（钱）=3.73 g， the dosages of Glehniae Radix， Ophiopogonis Radix and Angelicae Sinensis Radix were 5.60 g， the dosages of Lycii Fructus and Rehmanniae Radix were 11.19 g， the dosage of Toosendan Fructus was 7.46 g. These decoction pieces were boiled and warm decoction was taken. According to ancient medical records， the formula always has the effect of nourishing Yin and relieving Qi of liver. It is used to treat syndrome of stagnation of liver-Qi and deficiency of liver-Yin and kidney-Yin， which can be seen with pain in chest， stomach and flank， acerbity and vomiting， dry throat and mouth， red tongue， weak pulse or deficiency of string and hernia. Here， the source， processing and others of Yiguanjian were clarified， providing a literature reference for the development and application of this famous classical formula.

Comprehensive profiling and characterization of the absorbed components and metabolites in mice serum and tissues following oral administration of Qing-Fei-Pai-Du decoction by UHPLC-Q-Exactive-Orbitrap HRMS / 中国天然药物

Qing-Fei-Pai-Du decoction (QFPDD) is a Chinese medicine compound formula recommended for combating corona virus disease 2019 (COVID-19) by National Health Commission of the People's Republic of China. The latest clinical study showed that early treatment with QFPDD was associated with favorable outcomes for patient recovery, viral shedding, hospital stay, and course of the disease. However, the effective constituents of QFPDD remain unclear. In this study, an UHPLC-Q-Orbitrap HRMS based method was developed to identify the chemical constituents in QFPDD and the absorbed prototypes as well as the metabolites in mice serum and tissues following oral administration of QFPDD. A total of 405 chemicals, including 40 kinds of alkaloids, 162 kinds of flavonoids, 44 kinds of organic acids, 71 kinds of triterpene saponins and 88 kinds of other compounds in the water extract of QFPDD were tentatively identified via comparison with the retention times and MS/MS spectra of the standards or refereed by literature. With the help of the standards and in vitro metabolites, 195 chemical components (including 104 prototypes and 91 metabolites) were identified in mice serum after oral administration of QFPDD. In addition, 165, 177, 112, 120, 44, 53 constituents were identified in the lung, liver, heart, kidney, brain, and spleen of QFPDD-treated mice, respectively. These findings provided key information and guidance for further investigation on the pharmacologically active substances and clinical applications of QFPDD.

Clinical features of 76 Chinese patients with paroxysmal nocturnal haemoglobinuria / 中华血液学杂志

<p><b>OBJECTIVE</b>To further analyse the relationship between the new technology and clinical characteristics in paroxysmal nocturnal haemoglobinuria (PNH) patients, and summarize the data of PNH during the past 15 years in China.</p><p><b>METHODS</b>76 consecutive patients with PNH diagnosed in Peking Union Medical Colleague Hospital from 1997 - 2011 retrospectively.</p><p><b>RESULTS</b>Most of the patients were diagnosed based on flow cytometric data. There were 46 male and 30 female patients. The median age at diagnosis was 40 (10 - 74). 46 (60.5%) patients presented with classical PNH, 16 (21.1%) pancytopenia, and 14 (18.4%) thrombosis. Anatomic locations of first thrombosis were intra abdominal in 7 patients, lower extremities in 3 patients, intracerebral in 2 patients, and pulmonary thrombosis in 2 patients. The size of PNH clone at first determination (shown by CD55 and CD59 negative percentage) was (61.23 ± 27.47)% and (60.24 ± 25.59)% on neutrophils; (34.24 ± 25.50)% and (32.22 ± 23.12)% on erythrocytes, respectively. The mean LDH level was (1199.2 ± 893.5) U/L. In our cohort, 13(17.0%) patients suffered from renal deficiency, 12 (15.8%) patients cholecystolithiasis, 10 (13.2%) patients hemorrhage and 9 (11.8%) patients infections. In a median of 7-year (range 0.5 - 20 years) follow-up (68 patients), 2 (2.9%) patients developed into myelodysplastic syndromes/ acute myeloid leukemia, 1(1.5%) patient ovary cancer, 11(14.5%) patients died. Patients with thrombosis had higher percentage of CD59 negative neutrophils \[(73.45 ± 22.32)%\] compared with those without thrombosis \[(58.3 ± 20.2)%\] (P < 0.05).</p><p><b>CONCLUSIONS</b>The cohort had higher percentage of classical hemolysis, thrombosis and renal dysfunction compared with previous reports in China. Patients with thrombotic events had higher percentages of CD55 and CD59 negative neutrophils.</p>

Erythroleukemia - a subtype of myelodysplastic syndrome? / 中国实验血液学杂志

In order to study whether erythroleukemia was really a subtype of acute leukemia, the clinical laboratory characteristics and development of disease in 21 cases of erythroleukemia were analyzed. The results indicated that the percentage of patients with leucocytopenia, anemia and thrombocytopenia were 42.9%, 81% and 81% respectively at the time of diagnosis. These were 85.7% of patients with myelocytes and premonocyte, 52.4% of patients with erythroblast in their blood smear respectively. All of the bone marrow showed active or significantly active proliferation. The median percentage of erythro-lineage, myeloblast of NEC and displasia were (58.3 +/- 8.0)%, (58.0 +/- 18.4)% and 66.7% respectively, that is different from typical AML. 52.4% of M(6) patients transferred to RAEB/RAEB-T and AML-M(2) subtype in the disease progression. 11/19 cases (57.4%) achieved remission (CR 10; PR 1) after chemotherapy. The median remission length were 6 months for CR patients and 2 months for PR patients, but most of CR patients displayed obvious displasia of bone marrow and cytopenia of blood in the period of CR. The median survival length of M(6) and MDS-->M(6) from time of diagnosis were 13.0 +/- 13.2 and 2.3 +/- 1.3 months respectively. It is concluded that there are differences between M(6) and typical AML. Most of M(6) patients would rather be classified MDS RAEB and RAEB-t with over-hyperplasia of erythron lineage than a subtype of AML.

Expressions of MIP-1alpha, MCP-1 and their receptors CCR-1, CCR-2 in chronic myeloid leukemia cells / 中国实验血液学杂志

This study was aimed to explore the expression of MIP-1alpha, MCP-1 and their receptors CCR-1, CCR-2 in bcr/abl fusion gene positive CML cells, and to study the effects of P210(bcr/abl) fusion protein tyrosine kinase on expression of MIP-1alpha, MCP-1 and their receptors CCR-1, CCR-2 mRNAs in chronic myeloid leukemia cells. The expression levels of MIP-1alpha, MCP-1 and their receptors CCR-1, CCR-2 mRNA were detected by semi-quantitative RT-PCR in bcr/abl negative cells, bcr/abl positive cells, and P210(bcr/abl)-Rb-C-Box positive cells. The results showed that MIP-1alpha and CCR-1 mRNAs were expressed in bcr/abl negative cells, but not in positive cells. Both MCP-1 and CCR-2 mRNA cannot be detected in both bcr/abl positive and negative cells. After inhibiting P210(bcr/abl) tyrosine kinase activity by Rb-C-Box, expressions of MIP-1alpha and CCR-1 mRNAs were restored to normal (similar to P210(bcr/abl) negative cells). It is concluded that P210(bcr/abl) fusion protein inhibits the expression of MIP-1alpha and CCR-1 in chronic myeloid leukemia cells, but does not inhibit MCP-1 and CCR-2 mRNA expressions in these leukemia cells.

Low dose all-trans retinoic acid and androgen therapy for patients with myelodysplastic syndrome / 中国实验血液学杂志

To explore therapeutic efficacy of androgens and low dose all-trans retinoic acid (ATRA) for myelodysplastic syndrome (MDS) patients, 55 patients of MDS were observed, including 41 cases of refractory anemia (RA), 11 cases of refractory anemia with excess of blasts (RAEB), 2 cases of refractory anemia with excess of blasts in transformation (RAEB-t) and 1 case of chronic myeloic-monocytic leukemia (CMML). These patients received danazol (600 mg/day) or stanazol (6 mg/day) and ATRA (10 mg/day) for at least 3 months. The results showed that according to MDS international working group response criteria, at the end of three months,complete remission (CR) was seen in 1 patient, partial remission (PR) was found in 2 patients. Hematologic improvement: major response (MaR) were seen in 15 patients, minor response (MiR) were seen in 4 patients. The total response rate was 35.8%. In conclusion, danazol or stanazol in combination with low dose ATRA are partialy effective in therapy for patients with low-risk myelodysplastic syndrome.

Effects of bcr/abl fusion gene on expression of beta1 integrin and L-selectin in mouse chronic myeloid leukemia cells / 中华血液学杂志

<p><b>OBJECTIVES</b>To explore the effects of p210 bcr/abl fusion gene on expression of beta1 integrin and L-selectin mRNAs in mouse chronic myeloid leukemia (CML) cells.</p><p><b>METHODS</b>Comparisons of beta1 integrin and L-selectin mRNA levels among p210 bcr/abl negative, p210 bcr/abl positive, and p210 bcr/abl-Rb-C-Box positive cells were undertaken by quantity RT-PCR.</p><p><b>RESULTS</b>In p210 bcr/abl positive cells, L-selectin mRNA level was decreased, but beta1 integrin mRNA expression had no change as compared to those in p210 bcr/abl negative cells. When inhibition of bcr-abl tyrosine kinase activity by Rb-C-Box, the L-selectin mRNA expression restored to normal (similar to p210 bcr/abl negative cells).</p><p><b>CONCLUSION</b>p210 bcr/abl oncoprotein inhibits expression of L-selectin mRNA, but not of beta1 integrin mRNA.</p>

Analysis of caspases activity of hematopoietic progenitor cells and its significance in myelodysplastic syndromes / 中华血液学杂志

<p><b>OBJECTIVE</b>To investigate the changes of apoptosis and the activity of caspases 3 and 9 in bone marrow hematopoietic progenitor cells in myelodysplastic syndromes (MDS).</p><p><b>METHODS</b>Bone marrow hematopoietic progenitor cells (including both CD(34)(+) and CD(34)(-) cells) were collected by negative selection in 34 patients with MDS. Apoptosis was measured with Annexin V assay and activities of caspases 3 and 9 by spectrophotometer.</p><p><b>RESULTS</b>1. Apoptosis was significantly increased in MDS-RA (39.5%, P < 0.01) and MDS-RAEB (31.0%, P < 0.05), but was not different statistically in MDS-RAEBt/AML (18.8%) compared with that of control. 2. Activities of caspases 3 and 9 increased 45 and 20 fold in MDS-RA, increased 14 and 2 fold in MDS-RAEB, respectively and was not increased in MDS-RAEBt/AML compared with that of control. 3. Apoptosis and activities of caspases 3 and 9 reduced in 3 cases of MDS-RAEB group who progressed into AML.</p><p><b>CONCLUSION</b>Increased activities of caspases 3 and 9 may be one of causes of excessive apoptosis in MDS. With progress to AML, activities of caspases 3 and 9 and apoptosis reduced. Reduced activity of caspase 9 may result in apoptosis "escape" and progression into AML.</p>