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Hypercholesterolemia is mainly caused by abnormal lipoprotein metabolism and can increase the risk of cardiovascular disease. Angiopoietin-like protein 3 (ANGPTL3) can increase low-density lipoprotein cholesterol (LDL-C) and other lipids by inhibiting lipoprotein lipase activity. Evinacumab is a monoclonal antibody against ANGPTL3, it can decrease levels of LDL-C and has shown potential benefit in patients with homozygous familial hypercholesterolemia (HoFH).A comprehensive literature search was conducted in PubMed (January 2000 to August 2021). Key search terms included ANGPTL3, evinacumab and HoFH. Other sources were derived from product labeling and ClinicalTrials.gov. All English-language articles identified from the data sources were reviewed and evaluated. Phase 1, 2 and 3 clinical trials were included. The pharmacological characteristics, clinical evidence, and safety of evinacumab were reviewed.Evinacumab is an ANGPTL3 inhibitor. Phase 3 clinical trials found that in patients with HoFH, evinacumab reduced LDL-C by 47%, but placebo increased by 2%. Evinacumab was well-tolerated. Common adverse events included nasopharyngitis, influenza-like illness, dizziness, rhinorrhea, and nausea. It has the potential to become a valuable treatment option for patients with HoFH.

Asymmetric reduction of electronically activated alkenes by ene reductases (ERs) is an attractive approach for the production of enantiopure chiral products.

Bioproduction of optical pure (R)-citronellal from (E/Z)-citral at high substrate loading remains challenging. Low catalytic efficiency of (R)-stereoselective ene reductases towards crude citral mixture is one of the major bottlenecks. Herein, a structure-based engineering strategy was adopted to enhance the catalytic efficiency and stereoselectivity of an ene reductase (OYE2p) from Saccharomyces cerevisiae YJM1341 towards (E/Z)-citral. On basis of homologous modelling, molecular docking analysis and alanine scanning at the binding pocket of OYE2p, a mutant Y84A was obtained with simultaneous increase in catalytic efficiency and stereoselectivity. Furthermore, site-saturation mutagenesis of Y84 yielded seven mutants with improved activity and stereoselectivity in the (E/Z)-citral reduction. Among them, the variant Y84V exhibited an 18.3% and 71.3% rise in catalytic efficiency (kcat /Km ) for (Z)-citral and (E)-citral respectively. Meanwhile, the stereoselectivity of Y84V was improved from 89.2% to 98.0% in the reduction in (E/Z)-citral. The docking analysis and molecular dynamics simulation of OYE2p and its variants revealed that the substitution Y84V enabled (E)-citral and (Z)-citral to bind with a smaller distance to the key hydrogen donors at a modified (R)-selective binding mode. The variant Y84V was then co-expressed with glucose dehydrogenase from Bacillus megaterium in E. coli D4, in which competing prim-alcohol dehydrogenase genes were deleted to prevent the undesired reduction in the aldehyde moiety of citral and citronellal. Employing this biocatalyst, 106 g l-1 (E/Z)-citral was completely converted into (R)-citronellal with 95.4% ee value and a high space-time yield of 121.6 g l-1 day-1 . The work highlights the synthetic potential of Y84V, which enabled the highest productivity of (R)-citronellal from (E/Z)-citral in high enantiopurity so far.

Background: D-xylonic acid is a versatile platform chemical with wide potential applications as the water reducer and disperser for cement and the precursor for 1,4-butanediol and 1,2,4-tributantriol. Microbial production of D-xylonic acid with bacteria like Gluconobacter oxydans from cheap lignocellulosic feedstock is generally regarded as one of the most promising and cost-effective methods to industrial production, but xylonic acid productivity is reduced by high substrate inhibition and hydrolysate inhibitors. Results: D-xylonic acid productivity of G. oxydans DSM2003 was improved by overexpressing the mGDH gene, which encoded the membrane-bound glucose dehydrogenase. Using the mutated plasmids based on pBBR1MCS-5 in our previous work, the recombinant strain G. oxydans/pBBR-R3510-mGDH with the significant improvement in D-xylonic acid production and the strengthened tolerance to hydrolysate inhibitors was obtained. The fed-batch biotransformation of D-xylose by this recombinant strain reached the record high titer (588.7 g/L), yield (99.4%), and space-time yield (8.72 g/L/h). Moreover, up to 246.4 g/L D-xylonic acid was produced directly from corn stover hydroxylates without detoxification at a yield of 98.9% and a space-time yield of 11.2 g/L/h. In addition, G. oxydans/pBBR-R3510-mGDH performed strong tolerance to typical inhibitors, i.e., formic acid, furfural, and 5-hydroxymethylfurfural. Conclusion: Through overexpression of mgdh in G. oxydans, we obtained a recombinant strain G. oxydans/pBBR-R3510-mGDH. It was capable to efficiently produce xylonic acid from the corn stover hydrolysate under high concentrations of inhibitors. The high D-xylonic acid productivity made G. oxydans/pBBR-R3510-mGDH an attractive choice for biotechnical production.

Objectives: 3,4-Dihydroxybutyric acid (3,4-DHBA) is a multi-functional C4 platform compound with wide applications in the synthesis of materials and pharmaceuticals. Currently, although the biosynthetic pathway for the production of 3,4-DHBA has been developed, low productivity still hampers its use on large scales. Here, a non-natural four-steps biosynthetic pathway was established in recombinant E. coli with a combinatorial strategy.Results: Firstly, several aldehyde dehydrogenases (ALDHs) were screened and characterized for catalyzing the dehydrogenation of 3,4-dihydroxybutanal (3,4-DHB) to 3,4-DHBA through in vitro enzyme assays. Secondly, a recombinant E. coli was successfully constructed to generate 3,4-DHBA from D-xylose by introducing the pathway containing BsGDH, YagF, PpMdlC and ALDH into E. coli with 3.04 g/L 3,4-DHBA obtained. Then, disruption of competing pathways by deleting xylA, ghrA, ghrB and adhP genes contributed to increase the accumulation of 3,4-DHBA by 87%. Final, fusion expression of PpMdlC and YagF resulted in an enhancement of 3,4-DHBA titer (7.71 g/L), as the highest titer reported so far.Conclusions: These results showed that deleting competing pathways and constructing fusion protein could significantly improve the 3,4-DHBA titer in engineered E. coli.

Background Photocontrol of protein activity has become a helpful strategy for regulating biological pathways. Herein, a method for the precise and reversible photocontrol of oxidase activity was developed by using the conformational change of the AsLOV2 domain. Results The AsLOV2 domain was inserted into the nonconserved sites exposed on the surface of the AdhP protein, and the alov9 fusion was successfully screened for subsequent optical experiments under the assumption that neither of these actions affected the original activity of AdhP protein. The activity of alov9 was noticeably inhibited when the fusion was exposed to 470 nm blue light and recovered within 30 min. As a result, we could precisely and reversibly photocontrol alov9 activity through the optimization of several parameters, including cofactor concentration, light intensity, and illumination time. Conclusions An efficient method was developed for the photoinhibition of enzymatic activity based on the insertion of the light-sensitive AsLOV2 domain, providing new ideas for photocontrolling metabolic pathways without carriers in the future.

Objective To review the pharmacological characteristics, clinical evidence, and place in therapy of satralizumab for the treatment of neuromyelitis optica spectrum disorders (NMOSDs). Data Sources A comprehensive literature search was conducted in PubMed (January 2000 to October 15, 2020). Key search terms included satralizumab and neuromyelitis optica spectrum disorders. Other sources were derived from product labeling and ClinicalTrials.gov. Study Selection and Data Extraction All English-language articles identified from the data sources were reviewed and evaluated. Phase I, II, and III clinical trials were included. Data Synthesis NMOSD is an autoimmune disease characterized by inflammatory lesions in the optic nerves and spinal cord. Interleukin-6 is involved in the pathogenesis of the disorder. Satralizumab is a humanized monoclonal antibody targeting the interleukin-6 receptor. Phase III trials showed that protocol-defined relapse was 30% for satralizumab and 50% for placebo ( P = 0.018) when patients with NMOSD were treated with satralizumab monotherapy; protocol-defined relapse was 20% for satralizumab and 43% for placebo ( P = 0.02) when satralizumab was added to immunosuppressant treatment. Satralizumab is generally well tolerated, with common adverse effects including injection-related reaction. Relevance to Patient Care and Clinical Practice Satralizumab has the potential to become a valuable treatment option for patients with NMOSD. Conclusion Satralizumab appears to be safe and effective as monotherapy or in combination with an immunosuppressant for patients with NMOSD and has the potential to become a valuable treatment option for these patients.

Additional file 1: Figure S1. Three-dimensional structure of alov1-10 fusions. Figure S2. SDS-PAGE analsysis of the purification of alov1-10. Figure S3. Screening unconservative sites from surface-exposed loops by sequence alignment. Figure S4. Circular dichroism spectra of the alov9 under dark and light conditions. Table S1. The primers of alov1-10 fusions.

A NAD(P)H-dependent enoate reductase (OYE2p) from Saccharomyces cerevisiae YJM1341 was discovered by genome data mining for asymmetric reduction of (E/Z)-citral to (R)-citronellal with high enantioselectivity. This enzyme was heterologously expressed in E. coli and characterized for its biocatalytic properties. OYE2p was identified with reduction activities toward a diverse range of ɑ,β-unsaturated compounds bearing conjugated aldehyde, ketone, imide, carboxylic acid and ester. OYE2p showed the highest specific activity at 40 °C and a pH optimum at 7.0–8.0. The stability of OYE2p was rather pH-independent, and the half-life time values of the enzyme at pH 6.0–8.0 were more than 257 h. With regard to the reduction of (E)-citral and (Z)-citral, OYE2p exhibited different selectivity patterns. (E)-citral was exclusively reduced to (R)-citronellal by OYE2p in ≥ 99% ee, which was independent on pH. OYE2p produced both enantiomers of citronellal from (Z)-citral, but showed (R)-citronellal formation tendency, and the ee value of (R)-citronellal was affected by pH in the reaction system. Accordingly, the ee values for (R)-citronellal formation increased with the increasing levels of E-isomer in the (E/Z)-citral mixture as well as the increase of pH. Under the reaction conditions (30 °C and pH 8.6), using purified OYE2p as catalyst, 200 mM (E/Z)-citral (an approximately 10:9 mixture of geometric E-isomer and Z-isomer) was efficiently converted to (R)-citronellal with 88.8% ee and 87.2% yield. All these positive features demonstrate high potential of OYE2p for practical synthesis of (R)-citronellal and in asymmetric reduction of activated alkenes.

A cytosolic medium-chain alcohol dehydrogenase Gox0313 from Gluconobacter oxydans DSM2003 was heterologously expressed in Escherichia coli BL21 (DE3) and the resulting proteins were purified and characterized. The recombinant enzyme was confirmed to have a good ability to selectively oxidize the terminal hydroxyl group of varied aliphatic and aromatic diols to the corresponding hydroxyl aldehydes, with no oxidative activities toward hydroxyl aldehydes in the presence of NAD+. This enzyme could not oxidize sec-alcohols. Among the primary diols, ethylene glycol was efficiently converted to glycolaldehyde by Gox0313 coupled with NADH oxidase-2 (NOX-2) from Lactobacillus brevis ATCC367 for NAD+ regeneration. Under the optimal conditions using this enzyme-coupled system (1 U/mL Gox0313 and 4 U/mL NOX-2), 42.32 mM glycolaldehyde was produced from 50 mM ethylene glycol in 8 h with a yield of 83.2%. When the enzyme concentration of Gox0313 was increased to 120 U/mL in the reaction, 500 mM of ethylene glycol was converted to 484.2 mM of glycolaldehyde in 14 h, resulting in a yield of 96.8%. With respect to the superior catalytic activity to primary diols, Gox0313 might be a potentially promising biocatalyst for bioproduction of glycolaldehyde and other hydroxyl aldehydes.

To characterize a novel ene-reductase from Meyerozyma guilliermondii and achieve the ene-reductase-mediated reduction of activated C=C bonds. The gene encoding an ene-reductase was cloned from M. guilliermondii. Sequence homology analysis showed that MgER shared the maximal amino acid sequence identity of 57 % with OYE2.6 from Scheffersomyces stipitis. MgER showed the highest specific activity at 30 °C and pH 7 (100 mM sodium phosphate buffer), and excellent stereoselectivities were achieved for the reduction of (R)-carvone and ketoisophorone. Under the reaction conditions (30 °C and pH 7.0), 150 mM (R)-carvone could be completely converted to (2R,5R)-dihydrocarvone within 22 h employing purified MgER as catalyst, resulting in a yield of 98.9 % and an optical purity of >99 % d.e. MgER was characterized as a novel ene-reductase from yeast and showed great potential for the asymmetric reduction of activated C=C bonds of α,β-unsaturated compounds.

Additional file 1: Figure S1. Amino acid sequence alignment of CR-1 (GenBank accession number: CP012832.1), CR-2 (AY267012.1), CR-3 (EU877965.1), and CR-4 (CP003119.1). The alignment was performed with the program DNAMAN (http://www.lynnon.com/). Gaps in the aligned sequences are indicated by dots. Highly similar residues are colored in red and framed in blue, while identical residues are in white and on a red background.

A novel phosphate-solubilizing bacterium HPP16 from plant rhizosphere of Shandong University of Science and Technology districts of Qingdao (China) was isolated and the effects on promoting growth of mung bean (Phaseolus radiatus) seedlings in Campus and Jinshatan; two kinds of acidic soils were studied. HPP16 was identified as Enterobacter asburiae on the basis of 16S rDNA sequencing. It was Indole-3-acetic acid producer, synthesized siderophores and showed acid phosphatase activity. After mung bean was inoculated with HPP16, the germination rate and healthy stand in A-2 (inoculated with fermentation liquid) increased by 26 and 25% compared to A-4 (inoculated with the distilled water; negative control), and were 26 and 31.7% in B-2 (inoculated with fermentation liquid) compared to B-4 (inoculated with the distilled water, negative control). The individual plant height, fresh weight and dry weight in A-2 increased by 7, 10 and 6% compared to A-4, and increased by 8.5, 24 and 9% in B-2 compared to B-4. Mung bean could also increase to absorb K(+), Na(+) and Mg(2+) and improve the production of endogenous indole acetic acid (IAA), and also it reduced the production of abscisic acid (ABA). Findings of this study suggest that HPP16 may be exploited for developing a potential source of biofertilizer.

Combustion characteristics of JA2 propellant were studied both experimentally and theoretically. Its steady-state burning behavior was investigated using an optical strand burner. The parameters measured were the regression rate, subsurface temperature profile, and burning surface temperature at different initial temperatures (-40

Spray combustion tests of gaseous oxygen atomized sprays of RP-1 gel propellants with ultra-fine aluminum particles were performed in a rocket engine. The addition of aluminum particles to RP-1 gel propellants has the potential to significantly increase the heat of reaction over neat RP-1 due to the high volumetric energy release of the aluminum. Alex® powders, which have an average particle size of 100 nanometers, are formed by exploding aluminum wires. The use of these nano-sized particles can, theoretically, lead to more complete combustion, and thus, lead to performance increases such as higher flame temperature, increased specific impulse, and greater c* combustion efficiency. The engine operating conditions were as follows: chamber pressures ranging from 1-2.8 MPa (150-400 psia); gel propellant mass flow rates ranging from 8-40 g/s; gaseous oxygen mass flow rates ranging from 14-60 g/s; and oxygen-tofuel (O/F) ratios ranging from 0.5-5.0. The percentage of Alex® particles in the RP-1 gel propellants ranged from 0-55% by weight. The c* combustion efficiency was found to range from 60-99%. Results show that among the formulations, the RP-1 gel propellant with 5% of Alex® powders by weight appears to be the best in terms of range of c* efficiencies and the least amount of data scatter.

Background (R)-[3,5-bis(trifluoromethyl)phenyl] ethanol [(R)-3,5-BTPE] is a valuable chiral intermediate for Aprepitant (Emend) and Fosaprepitant (Ivemend). Biocatalyzed asymmetric reduction is a preferred approach to synthesize highly optically active (R)-3,5-BTPE. However, the product concentration and productivity of reported (R)-3,5-BTPE synthetic processes remain unsatisfied. Results A NADPH-dependent carbonyl reductase from Lactobacillus kefir (LkCR) was discovered by genome mining for reduction of 3,5-bis(trifluoromethyl) acetophenone (3,5-BTAP) into (R)-3,5-BTPE with excellent enantioselectivity. In order to synthesize (R)-3,5-BTPE efficiently, LkCR was coexpressed with glucose dehydrogenase from Bacillus subtilis (BsGDH) for NADPH regeneration in Escherichia coli BL21 (DE3) cells, and the optimal recombinant strain produced 250.3 g/L (R)-3,5-BTPE with 99.9% ee but an unsatisfied productivity of 5.21 g/(L h). Then, four different linker peptides were used for the fusion expression of LkCR and BsGDH in E. coli to regulate catalytic efficiency of the enzymes and improved NADPH-recycling efficiency. Using the best strain (E. coli/pET-BsGDH-ER/K(10 nm)-LkCR), up to 297.3 g/L (R)-3,5-BTPE with enantiopurity >99.9% ee was produced via reduction of as much as 1.2 M of substrate with a 96.7% yield and productivity of 29.7 g/(L h). Conclusions Recombinant E. coli/pET-BsGDH-ER/K(10 nm)-LkCR was developed for the bioreduction of 3,5-BTAP to (R)-3,5-BTPE, offered the best results in terms of high product concentration and productivity, demonstrating its great potential in industrial manufacturing of (R)-3,5-BTPE. Electronic supplementary material The online version of this article (doi:10.1186/s12934-016-0585-5) contains supplementary material, which is available to authorized users.