Glutamine synthetase (GS) is a critical enzyme in nitrogen metabolism regulation and plays an essential role in the metabolic pathways involved in microbial growth and development. Penicillium brevicompactum, known for its rich repertoire of secondary metabolites, including mycophenolic acid (MPA), lacks research on the regulatory mechanisms of GS within this species. This study aimed to investigate the influence of GS on the growth, sporulation, and secondary metabolism of P.
View Article and Find Full Text PDF()-Citronellal is a key chiral precursor of high-value chemicals, such as the best-selling flavor compound (-)-menthol; however, the conventional synthesis suffers from low yield and unsatisfactory enantioselectivity. In this study, we developed a highly atom-efficient hydrogen-borrowing cascade for the synthesis of ()-citronellal from geraniol using alcohol dehydrogenase from K12 (AdhP) and ene-reductase from YJM1341 (OYE2p). The key rate-limiting enzyme, AdhP, was subjected to structure-guided semirational engineering, and the triple mutant AdhP (M3) was obtained that demonstrated a 1.
View Article and Find Full Text PDFBackground: Escherichia coli is a frequently used host for heterologous protein expression, but its expression efficiency is hindered by several limitations, such as formation of inclusion bodies and proteolytic degradation.
Methods And Results: In this study, we employed high-density fermentation of heterologous protein production in a 5-L bioreactor, resulting in a yield 2.25 times higher than that of the control group.
Lysine cyclodeaminase (LCD)-mediated synthesis of l-pipecolic acid (l-PA) from l-lysine (l-Lys) is a promising approach. However, only one LCD has been reported, and its inadequate activity limits industrial applications. To address this problem, a substrate analogue-guided enzyme mining strategy was employed.
View Article and Find Full Text PDFProtein-based therapeutic agents currently used for targeted tumor therapy exhibit limited penetrability, nonspecific toxicity, and a short circulation half-life. Although targeting cell surface receptors improves cancer selectivity, the receptors are also slightly expressed in normal cells; consequently, the nonspecific toxicity of recombinant protein-based therapeutic agents has not been eliminated. In this study, an allosteric-regulated protein switch was designed that achieved cytoplasmic reorganization of engineered immunotoxins in tumor cells via interactions between allosteric self-splicing elements and cancer markers.
View Article and Find Full Text PDFCoproporphyrin III (CP III), a natural porphyrin derivative, has extensive applications in the biomedical and material industries. has previously been engineered to highly accumulate the CP III precursor 5-aminolevulinic acid (ALA) through the C4 pathway. In this study, a combination of cytoplasmic metabolic engineering and mitochondrial compartmentalization was used to enhance CP III production in .
View Article and Find Full Text PDF(R)-selective transaminases have the potential to act as efficient biocatalysts for the synthesis of important pharmaceutical intermediates. However, their low catalytic efficiency and unfavorable equilibrium limit their industrial application. Seven (R)-selective transaminases were identified using homologous sequence mining.
View Article and Find Full Text PDFHeme has attracted considerable attention due to its indispensable biological roles and applications in healthcare and artificial foods. The development and utilization of edible microorganisms instead of animals to produce heme is the most promising method to promote the large-scale industrial production and safe application of heme. However, the cytotoxicity of heme severely restricts its efficient synthesis by microorganisms, and the cytotoxic mechanism is not fully understood.
View Article and Find Full Text PDFThe bioderacemization of racemic phosphinothricin (D, L-PPT) is a promising route for the synthesis of l-phosphinothricin (L-PPT). However, the low activity and tolerance of wild-type enzymes restrict their industrial applications. Two stereocomplementary aminotransferases with high activity and substrate tolerance were identified in a metagenomic library, and a one-pot, two-stage artificial cascade biocatalytic system was developed to produce L-PPT through kinetic resolution and asymmetric amination.
View Article and Find Full Text PDFBiotechnol Biofuels Bioprod
May 2024
Background: Ergothioneine (EGT) is a distinctive sulfur-containing histidine derivative, which has been recognized as a high-value antioxidant and cytoprotectant, and has a wide range of applications in food, medical, and cosmetic fields. Currently, microbial fermentation is a promising method to produce EGT as its advantages of green environmental protection, mild fermentation condition, and low production cost. However, due to the low-efficiency biosynthetic process in numerous cell factories, it is still a challenge to realize the industrial biopreparation of EGT.
View Article and Find Full Text PDFSheng Wu Gong Cheng Xue Bao
March 2024
The biotechnology industry is a strategic emerging industry in our country, holding a crucial position in the national economy. The training of innovative high-quality professionals carries immense significance. As the cornerstone course in biotechnology, "Enzyme Engineering" directly impacts the students' caliber and industry development.
View Article and Find Full Text PDFObjectives: Although Geobacillus are significant thermophilic bacteria source, there are no reports of thermostable esterase gene in Geobacillus jurassicus or rational design strategies to increase the thermal stability of esterases.
Results: Gene gju768 showed a highest similarity of 15.20% to esterases from Geobacillus sp.
(R)-selective transaminases show promise as catalysts for the asymmetric synthesis of chiral amines, which are building blocks of various small molecule drugs. However, their application is limited by poor substrate acceptance and low catalytic efficiency. Here, a potential (R)-selective transaminase from Fodinicurvata sediminis (FsTA) was identified through a substrate truncating strategy, and used as starting point for enzyme engineering toward catalysis of 4-hydroxy-2-butanone, a substrate that poses challenges in catalysis.
View Article and Find Full Text PDFAppl Microbiol Biotechnol
February 2024
Komagataella phaffii, a nonconventional yeast, is increasingly attractive to researchers owing to its posttranslational modification ability, strict methanol regulatory mechanism, and lack of Crabtree effect. Although CRISPR-based gene editing systems have been established in K. phaffii, there are still some inadequacies compared to the model organism Saccharomyces cerevisiae.
View Article and Find Full Text PDFHydration, a secondary activity mediated by nitrilase, is a promising new pathway for amide production. However, low hydration activity of nitrilase or trade-off between hydration and catalytic activity hinders its application in the production of amides. Here, natural C-terminal-truncated wild-type nitrilase, mined from a public database, obtained a high-hydration activity nitrilase as a novel evolutionary starting point for further protein engineering.
View Article and Find Full Text PDFIn this study, Lactiplantibacillus plantarum X7022 was applied to ameliorate memory impairment of aging mice induced by D-galactose. The strain showed specific choloylglycine hydrolysis ability based on in vitro investigation. Morris water maze test showed L.
View Article and Find Full Text PDFPenicillium brevicompactum is a critical industrial strain for the production of mycophenolic acid (MPA). However, the genetic background of Penicillium brevicompactum is unclear, and there are few tools available for genetic manipulation. To investigate its gene function, we first verified the feasibility of a pair of citrate synthase promoter (Pcit) and terminator (Tcit) from P.
View Article and Find Full Text PDFInvestigation of a novel thermophilic esterase gene from Geobacillus subterraneus DSMZ 13552 indicated a high amino acid sequence similarity of 25.9% to a reported esterase from Geobacillus sp. A strategy that integrated computer-aided rational design tools was developed to select mutation sites.
View Article and Find Full Text PDFL-malic acid (MA) is a vital platform chemical with huge market demand because of its broad industrial applications. A cell factory for MA production was engineered by strengthening the intrinsic pathway without inserting foreign genes into Trichoderma reesei. The native MA transporter gene in the T.
View Article and Find Full Text PDFBackground: Harnessing engineered Mycolicibacteria to convert cheap phytosterols into valuable steroid synthons is a basic way in the industry for the production of steroid hormones. Thus, C-19 and C-22 steroids are the two main types of commercial synthons and the products of C17 side chain degradation of phytosterols. During the conversion process of sterols, C-19 and C-22 steroids are often produced together, although one may be the main product and the other a minor byproduct.
View Article and Find Full Text PDFAppl Microbiol Biotechnol
August 2023
The engineered probiotic Escherichia coli Nissle 1917 (EcN) is expected to be employed in the diagnosis and treatment of various diseases. However, the introduced plasmids typically require antibiotics to maintain genetic stability, and the cryptic plasmids in EcN are usually eliminated to avoid plasmid incompatibility which may change the inherent probiotic characteristics. Here, we provided a simple design to minimize the genetic change of probiotics by eliminating native plasmids and reintroducing the recombinants carrying functional genes.
View Article and Find Full Text PDFBackground: The conversion of phytosterols to steroid synthons by engineered Mycolicibacteria comprises one of the core steps in the commercial production of steroid hormones. This is a complex oxidative catabolic process, and taking the production of androstenones as example, it requires about 10 equivalent flavin adenine dinucleotide (FAD). As the high demand for FAD, the insufficient supply of FAD may be a common issue limiting the conversion process.
View Article and Find Full Text PDF