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Background: Saccharomyces cerevisiae is often used as a cell factory for the production of S-adenosyl-L-methionine (SAM) for diverse pharmaceutical applications. However, SAM production by S. cerevisiae is negatively influenced by glucose repression, which is regulated by a serine/threonine kinase SNF1 complex. Here, a strategy of alleviating glucose repression by deleting REG1 (encodes the regulatory subunit of protein phosphatase 1) and overexpressing SNF1 (encodes the catalytic subunit of the SNF1 complex) was applied to improve SAM production in S. cerevisiae. SAM production, growth conditions, glucose consumption, ethanol accumulation, lifespan, glycolysis and amino acid metabolism were analyzed in the mutant strains.
Results: The results showed that the multiple effects of REG1 deletion and/or SNF1 overexpression exhibited a great potential for improving the SAM production in yeast. Enhanced the expression levels of genes involved in glucose transport and glycolysis, which improved the glucose utilization and then elevated the levels of glycolytic intermediates. The expression levels of ACS1 (encoding acetyl-CoA synthase I) and ALD6 (encoding aldehyde dehydrogenase), and the activity of alcohol dehydrogenase II (ADH2) were enhanced especially in the presence of excessive glucose levels, which probably promoted the conversion of ethanol in fermentation broth into acetyl-CoA. The gene expressions involved in sulfur-containing amino acids were also enhanced for the precursor amino acid biosynthesis. In addition, the lifespan of yeast was extended by REG1 deletion and/or SNF1 overexpression. As expected, the final SAM yield of the mutant YREG1ΔPSNF1 reached 8.28 g/L in a 10-L fermenter, which was 51.6% higher than the yield of the parent strain S. cerevisiae CGMCC 2842.
Conclusion: This study showed that the multiple effects of REG1 deletion and SNF1 overexpression improved SAM production in S. cerevisiae, providing new insight into the application of the SNF1 complex to abolish glucose repression and redirect carbon flux to nonethanol products in S. cerevisiae.
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http://dx.doi.org/10.1186/s12934-022-01900-7 | DOI Listing |
J Enzyme Inhib Med Chem
December 2025
Department of Pharmaceutical Sciences and Natural Products, Central University of Punjab, Bathinda, India.
The mitogen-activated protein kinase (MAPK) pathway-also known as the RAS/RAF/MEK/ERK pathway-is a critical signalling cascade involved in regulating cell growth, proliferation, and survival. First discovered in the early 1980s, the pathway's extracellular signal-regulated kinase (ERK) subfamily was identified in the 1990s. The ERK family includes several isoforms-ERK1, ERK2, ERK3, ERK5, and ERK6-with ERK1 (MAPK3) and ERK2 (MAPK1) being the most well-characterised and playing central roles in MAPK signalling.
View Article and Find Full Text PDFDalton Trans
September 2025
Department of Chemistry, Indian Institute of Technology Guwahati, Assam 781039, India.
Motivated by copper's essential role in biology and its wide range of applications in catalytic and synthetic chemistry, this work aims to understand the effect of heteroatom substitution on the overall stability and reactivity of biomimetic Cu(II)-alkylperoxo complexes. In particular, we designed a series of tetracoordinated ligand frameworks based on iso-BPMEN = (,-bis(2-pyridylmethyl)-','-dimethylethane-1,2-diamine) with varying the primary coordination sphere using different donor atoms (N, O, or S) bound to Cu(II). The copper(II) complexes bearing iso-BPMEN and their modified heteroatom-substituted ligands were synthesized and structurally characterized.
View Article and Find Full Text PDFComput Med Imaging Graph
August 2025
Beijing Huilongguan Hospital, Peking University Huilongguan Clinical Medical School, Beijing 100096, China. Electronic address:
Bipolar disorder (BD) is a debilitating mental illness characterized by significant mood swings, posing a substantial challenge for accurate diagnosis due to its clinical complexity. This paper presents CS2former, a novel approach leveraging a dual channel-spatial feature extraction module within a Transformer model to diagnose BD from resting-state functional MRI (Rs-fMRI) and T1-weighted MRI (T1w-MRI) data. CS2former employs a Channel-2D Spatial Feature Aggregation Module to decouple channel and spatial information from Rs-fMRI, while a Channel-3D Spatial Attention Module with Synchronized Attention Module (SAM) concurrently computes attention for T1w-MRI feature maps.
View Article and Find Full Text PDFAdv Mater
September 2025
Guangdong Provincial Key Laboratory of Optical Information Materials and Technology & Institute of Electronic Paper Displays, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou, 510006, P. R. China.
Establishing a low-resistance perovskite/ITO contact using self-assembled molecules (SAMs) is crucial for efficient hole transport in perovskite solar cells (PSCs) without a pre-deposited hole-transporting layer. However, SAMs at the buried interface often encounter issues like nonuniform distribution and molecular aggregation during the extrusion process, leading to significant energy loss. Herein, a molecular hybrid bridging strategy by incorporating a novel small molecule is proposed, (2-aminothiazole-4-yl)acetic acid (ATAA), featuring a thiazole ring and carboxylic acid group, along with the commonly used SAM, 4-(2,7-dibromo-9,9-dimethylacridin-10(9H)-yl)butyl)phosphonic acid (DMAcPA), into the perovskite precursor to synergistically optimize the buried interface.
View Article and Find Full Text PDFDigit Health
September 2025
Department of Respiratory and Critical Care Medicine, The Sixth Affiliated Hospital of Xinjiang Medical University, Urumqi, China.
Objective: Accurate segmentation of breast lesions, especially small ones, remains challenging in digital mammography due to complex anatomical structures and low-contrast boundaries. This study proposes DVF-YOLO-Seg, a two-stage segmentation framework designed to improve feature extraction and enhance small-lesion detection performance in mammographic images.
Methods: The proposed method integrates an enhanced YOLOv10-based detection module with a segmentation stage based on the Visual Reference Prompt Segment Anything Model (VRP-SAM).