The application of rational design in reallocating metabolic flux to accumulate desired chemicals is always restricted by the native regulatory network. In this study, recombinant Pichia pastoris was constructed for malic acid production from sole methanol through rational redistribution of metabolic flux. Different malic acid accumulation modules were systematically evaluated and optimized in P. pastoris. The recombinant PP-CM301 could produce 8.55 g/L malic acid from glucose, which showed a 3.45-fold increase compared to the parent strain. To improve the efficiency of site-directed gene knockout, NHEJ-related protein Ku70 was destroyed, whereas leading to the silencing of heterogenous genes. Hence, genes related to by-product generation were deleted via a specially designed FRT/FLP system, which successfully reduced succinic acid and ethanol production. Furthermore, a key node in the methanol assimilation pathway, glucose-6-phosphate isomerase was knocked out to liberate metabolic fluxes trapped in the XuMP cycle, which finally enabled 2.79 g/L malic acid accumulation from sole methanol feeding with nitrogen source optimization. These results will provide guidance and reference for the metabolic engineering of P. pastoris to produce value-added chemicals from methanol.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1002/bit.27575 | DOI Listing |
Food Chem
December 2024
BIOLAFFORT, 11 rue Aristide Berges, 33270 Floirac, France; UMR OENO, Université de Bordeaux, INRAE, INP, BSA, ISVV, 210 Chemin de Leysotte, 33882 Villenave d'Ornon, France. Electronic address:
The alcoholic fermentation of wine is mostly achieved by the species Saccharomyces cerevisiae that display a large variability for their ability to consume or produce malic acid. To better characterize the metabolism of such group of strains we explored their non-volatile metabolome using an untargeted LC-HRMS approach. The chemical classes and the putative structures of several hundred compounds where annotated using MS2 spectra using the SIRIUS software.
View Article and Find Full Text PDFPhytomedicine
January 2025
Zhejiang Provincial International S&T Cooperation Base for Active Ingredients of Medicinal and Edible Plants and Health, Zhejiang Provincial Key TCM Laboratory for Chinese Resource Innovation and Transformation, School of Pharmaceutical Sciences, Jinhua Academy, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, 310053, China. Electronic address:
Background: Acute pharyngitis (AP) is a common condition marked by inflammation of the oropharynx, which can lead to severe throat swelling, breathing difficulties, and even suffocation, significantly impacting quality of life. Despite the beneficial anti-inflammatory activity of Glycyrrhizae Radix Et Rhizoma (GRER) and Isoliquiritigenin (ISL), their pharmacological mechanisms against AP remain unclear.
Purpose: This study explores the mechanisms by which GRER treats AP, utilizing both transcriptomics and metabolomics approaches.
J Hazard Mater
January 2025
College of Chemical and Environmental Engineering, Hanjiang Normal University, Shiyan 442000, China. Electronic address:
Anal Chem
January 2025
The Jiangxi Province Key Laboratory for Diagnosis, Treatment, and Rehabilitation of cancer in Chinese Medicine, Jiangxi University of Chinese Medicine, Nanchang 330004, P. R. China.
An online reactive internal extraction electrospray ionization (iEESI) method was developed for the rapid determination of organic and inorganic speciation information for selenium in poultry tissue samples without complex sample pretreatment. The addition of citric acid as a reducing agent to the internal extraction solvent of methanol/acetic acid (99:1, V/V) for iEESI resulted in the reduction of selenate in the sample to selenite, accompanied by the production of malic acid as an oxidation product. The quantitative analysis of selenate was conducted by using malic acid.
View Article and Find Full Text PDFFoods
December 2024
Institute of Bioengineering, Research Center of Biotechnology of the Russian Academy of Sciences, 119071 Moscow, Russia.
In winemaking, malolactic fermentation (MLF), which converts L-malic acid to L-lactic acid, is often applied after the alcoholic fermentation stage to improve the sensory properties of the wine and its microbiological stability. MLF is usually performed by lactic acid bacteria, which, however, are sensitive to the conditions of alcoholic fermentation. Therefore, the development of wine yeast strains capable of both alcoholic fermentation and MLF is an important task.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!