Phenylpyruvic acid (PPA) is used as a food and feed additive and has a wide range of applications in the pharmaceutical, chemical and other fields. At present, PPA is mainly produced by chemical synthesis. With the green transformation of the manufacturing industry, biotransformation will be a good alternative for PPA production. The L-amino acid deaminase (PmiLAAD) from Proteus mirabilis has been widely studied for the production of PPA. However, the low yield limits its industrial production. To further enhance the production of PPA and better meet industrial demands, a more efficient synthesis method for PPA was established. In this study, PmiLAAD was heterologously expressed in Escherichia coli. Subsequently, a colorimetric reaction method was established to screen the strains with high PPA production. The semi-rational design of PmiLAAD was carried out, and the obtained triple-site mutant V18 (V437I/S93C/E417A) showed a 35% increase in catalytic activity compared with the wild type. Meanwhile, the effect of N-terminal truncation on the catalytic activity of the V18 mutant was investigated. After the optimization of the whole-cell conditions for the obtained mutant V18-N7, fed-batch conversion was carried out in a 5-L fermenter, and 44.13 g/L of PPA was synthesized with a conversion rate of 88%, which showed certain potential for industrial application. This study lays foundation for the industrial production of phenylpyruvic acid and also offers insights into the biosynthesis of other chemicals.
Escherichia coli/metabolism* ; Proteus mirabilis/genetics* ; Phenylpyruvic Acids/metabolism* ; Protein Engineering/methods* ; Recombinant Proteins/biosynthesis* ; Bacterial Proteins/metabolism*

L-tyrosine is one of the 20 amino acids that make up proteins and is an essential amino acid for mammals, often used as a nutritional supplement. The conventional methods for synthesizing L-tyrosine have some problems such as the production of many by-products, high requirements for production conditions, and environmental pollution. In this study, we designed and constructed a multi-enzyme cascade for the synthesis of L-tyrosine with alanine, glutamate, ammonium chloride, and phenol as substrates. Initially, the sources of glutamate oxidase, alanine aminotransferase, and tyrosine phenol lyase were screened and analyzed, which was followed by the identification of the rate-limiting enzyme in the reaction process. A colorimetric screening method was established, and the rate-limiting enzyme DbAlaA was engineered to enhance its activity by 40.0%. Subsequently, the reaction conditions, including temperature, pH, cell concentration, and surfactant and coenzyme dosages, were optimized. After optimization, the yield of L-tyrosine reached 9.93 g/L, with a alanine conversion rate of 54.90%. Finally, a feed-batch fermentation strategy was adopted, and the yield of L-tyrosine reached 56.07 g/L after 24 h, with a alanine conversion rate of 65.22%. This study provides a reference for the whole-cell catalytic synthesis of L-tyrosine and its industrialization.
Tyrosine/biosynthesis* ; Escherichia coli/metabolism* ; Tyrosine Phenol-Lyase/genetics* ; Multienzyme Complexes/metabolism* ; Fermentation

AIM: To investigate the effect and mechanism of ursolic acid on high glucose and high-fat injury of human aortic endothelial cells. METHODS: MTT method was used to select the appropriate injury concentration of high glucose and sodium palmitate and UA pre incubation concentration. The levels of NO and ROS, the release rate of lactate dehydrogenase and the activities of antioxidant enzymes including total superoxide dismutase, catalase and glutathione peroxidase were detected by kit. The expression of endothelial nitric oxide synthase, intercellular adhesion molecule, vascular cell adhesion molecule caspase-1 and GSDMD were detected by Western blot. The protective effect of UA on HAEC was observed. Hoechst33342 combined with PI fluorescence staining was used to detect the whole state of cell membrane to explore the occurrence of pyroptosis. RESULTS: Pre-incubation with UA (1 and 5 μmol/L) could reduce the damage of HAEC caused by high glucose and high fat (30 mmol/L Glu + 0.1 mmol/L SPA), enhance HAEC activity, increase NO release and eNOS protein expression, alleviate oxidative stress injury, reduce the protein expression of adhesion molecules and reduce the occurrence of pyroptosis. CONCLUSION: UA may reduce the damage of endothelial cells by inhibiting the oxidative stress response and the occurrence of pyroptosis induced by high glucose and high fat.

OBJECTIVETo analyze the diseases and effects of the manipulations to promoteby filiform needles, with the help of data mining technique.

METHODSLiterature about different manipulations to promoteby filiform needles in recent 60 years was collected in China National Knowledge Infrastructure(CNKI). Then databases were established to mine the relativities among the diseases, subjects, acupoints selection law,routes and directions of meridianand effects.

RESULTS①Total 489 articles were included. The basic manipulations with the frequency of 630 were on the top. The auxiliary and four methods ofrespectively appeared 70 times. The diseases in the internal medicine were treated with the basic and auxiliary methods of the higher frequencies, 311 and 44 times separately. While the four methods ofwere mostly used in the surgical area, 37 timestotally. ②The diseases treated from high to low by lifting, thrusting and twirling represented retention of urine, sequelae of stroke, pain in waist and lower limbs, of which the effect for retention of urine was better than those of the other two, and the lifting and thrusting method was superior to twirling. ③As for the auxiliary methods, 25 times were found about vibration needling; 18 times, twisting. The highest frequency of 6 times for the vibration needling was on the sequelae of stroke; while 4 times for the twisting, stranguria. ④As to the four methods of,was most frequently applied, and its highest frequency of 18 was onsyndrome.

CONCLUSIONSManipulations to promoteby filiform needles are crucial to achieving the effects of acupuncture. The basic methods are widely used in clinic and have been seen good efficacy. While the auxiliary means assist to promoteto stimulate the body,among which the four methods ofare mainly to smooth the meridians and driveof patients with surgical diseases and take meridian blocking the priority.

Combining with the data based on data mining,to collect the clinical experimental research ralating to thermal moxibustion from June 2010 to March 2015, and extract the representative clinical experimental research of clinical diseases. To summarize advances in clinic study of Thermal Moxibustion in recent five years.