98%
921
2 minutes
20
3-Hydroxypropionic acid (3-HP) is an important platform chemical proposed by the United States Department of Energy. 3-HP can be converted to a series of bulk chemicals. Biological production of 3-HP has made great progress in recent years. However, low yield of 3-HP restricts its commercialization. In this study, systematic optimization was conducted towards high-yield production of 3-HP in Klebsiella pneumoniae. We first investigated appropriate promoters for the key enzyme (aldehyde dehydrogenase, ALDH) in 3-HP biosynthesis, and found that IPTG-inducible tac promoter enabled overexpression of an endogenous ALDH (PuuC) in K. pneumoniae. We optimized the metabolic flux and found that blocking the synthesis of lactic acid and acetic acid significantly increased the production of 3-HP. Additionally, fermentation conditions were optimized and scaled-up cultivation were investigated. The highest 3-HP titer was observed at 83.8 g/L with a high conversion ratio of 54% on substrate glycerol. Furthermore, a flux distribution model of glycerol metabolism in K. pneumoniae was proposed based on in silico analysis. To our knowledge, this is the highest 3-HP production in K. pneumoniae. This work has significantly advanced biological production of 3-HP from renewable carbon sources.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4882505 | PMC |
http://dx.doi.org/10.1038/srep26932 | DOI Listing |
J Biotechnol
August 2025
Carl and Melinda Helwig Department of Biological and Agricultural Engineering, Kansas State University, Manhattan, KS 66506, USA. Electronic address:
3-Hydroxypropionic acid (3-HP) is a versatile platform chemical with wide-ranging industrial applications. This study presents a proof-of-concept approach for producing 3-HP from brewer's spent grain (BSG) using a novel one-pot CaO pretreatment method and an engineered, acid-tolerant Issatchenkia orientalis IoDY01H strain. The effects of acid type for pH adjusting of pretreated slurry, nitrogen supplementation, NaHCO addition, and BSG deproteinization were evaluated.
View Article and Find Full Text PDFACS Synth Biol
August 2025
Leiden Institute of Chemistry, Leiden University, Leiden 2300 RA, The Netherlands.
3-Hydroxypropionic acid (3-HP) serves as a crucial platform chemical with diverse applications across various industries. In this study, the oxaloacetate pathway was utilized for 3-HP production. This pathway involves the decarboxylation of oxaloacetate into malonic semialdehyde, catalyzed by branched-chain α-keto acid decarboxylase (KdcA), which is subsequently reduced to 3-HP by dehydrogenases.
View Article and Find Full Text PDFAppl Environ Microbiol
August 2025
School of Life Sciences, Shandong Province Key Laboratory of Applied Mycology, and Qingdao International Center on Microbes Utilizing Biogas, Qingdao Agricultural University, Qingdao, Shandong, People's Republic of China.
Unlabelled: AM1, a native formate-utilizing bacterium, has exhibited limited capacity to tolerate formate. In this study, we employed an adaptive laboratory evolution (ALE) strategy to develop an evolved strain FT3 derived from AM1, with enhanced formate tolerance. When cultivated with a mixture of carbon sources containing 90 mM formate and 30 mM methanol, the FT3 strain exhibited 5.
View Article and Find Full Text PDFAdv Sci (Weinh)
August 2025
Innovative Center of Cell Signaling Transduction and Synthetic Biology,Guangdong Provincial Key Laboratory of Plant Adaptation and Molecular Design, School of Life Sciences, Guangzhou University, 230 Wai Huan Xi Road, Guangzhou, Guangdong, 510006, P. R. China.
Enhancing microbial tolerance to target chemicals through conventional adaptive laboratory evolution (ALE) is time-consuming, labor-intensive, and further constrained by the challenge of balancing improved tolerance with maintaining optimal biosynthetic efficiency. Here, this work proposes a refined ALE strategy that combines initial mutagenesis with an automated microdroplet cultivation (MMC) system, thereby expediting the acquisition of tolerance phenotypes. Integrating a biosensor-assisted high-throughput screening platform enables identification of strains exhibiting advantageous "win-win" phenotypes, characterized by simultaneous improvements in both tolerance and biosynthetic capacity.
View Article and Find Full Text PDFBioresour Technol
December 2025
Department of Food Science, Purdue University, West Lafayette, IN 47907, USA; Whistler Center for Carbohydrate Research, Purdue University, West Lafayette, IN 47907, USA. Electronic address:
Efficient bioconversion of acetate-rich lignocellulosic biomass into value-added chemicals remains a major challenge due to the toxicity of acetic acid. In this study, we developed an acid-tolerant Issatchenkia orientalis strain (IoDY01H) capable of producing 3-hydroxypropionic acid (3-HP), a key bioplastic precursor, from glucose, xylose, and acetate. Using a Cas9-based genome editing system with a hygromycin B resistance marker, we introduced heterologous genes encoding xylose utilization and β-alanine-based 3-HP biosynthetic pathways into the I.
View Article and Find Full Text PDF