Mutagenesis studies on the sensitivity of Escherichia coli acetohydroxyacid synthase II to herbicides and valine

Lee, Yu-Ting; Duggleby, Ronald G.

doi:10.1042/bj3500069

Cited by 14 publications

(1 citation statement)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Terefore, they transferred the imidazolinonetolerant AHAS-large subunit (csr1-2) gene obtained from Arabidopsis thaliana in soybean. Tis helps in the synthesis of valine, leucine, and isoleucine branched-chain essential amino acids [157]. Te Embrapa (the Brazilian Agricultural Research Corporation) researcher group developed imidazolinone chemical class herbicide-tolerant soybean cultivar CV127 (Cultivance) having csr1-2 gene which was approved for commercial release by National Technical Commission on Biosecurity in Brazil [120].…”

Section: Enhancement Of Herbicide Resistance Using a Transgenic Approachmentioning

confidence: 99%

Improvement of Soybean Crop for Yield, Stress Tolerance, and Value-Added Products Using a Transgenic Approach

Shelke

Chambhare

Nikalje

et al. 2023

Advances in Agriculture

View full text Add to dashboard Cite

Soybean (Glycine max) is an economically important crop, ranking first among the edible oilseed crops in the world due to its oil content and nutritional value. Besides, it is used as a dietary supplement and a source of pharmaceuticals. The recent rapid climate changes and increasing global population have led to increasing demand for vegetable oil. In the recent past, advances in the field of plant biotechnology have revolutionized agricultural practices at a global level to enhance the yield of crops. This technology not only makes an impact on the agricultural market but also opens up new corridors for agriculture-related industrial applications of this important crop. Therefore, in the last two decades, soybean has gained attention for genetic improvement with remarkable developments in the manipulations of genes for the induction of desired characteristics. In this review, we introduced the transgenic approach as a promising tool for the improvement of soybean oilseed quality and productivity. Then, the enhancement of nutritional and pharmaceutical value together with biotic and abiotic stress-resistant ability was summarized and compared. The methods and strategies for achieving soybean crops with improved abiotic stress tolerance, productivity, and pharmaceutics are categorized to help with future research.

show abstract

Section: Enhancement Of Herbicide Resistance Using a Transgenic Approachmentioning

confidence: 99%

Improvement of Soybean Crop for Yield, Stress Tolerance, and Value-Added Products Using a Transgenic Approach

Shelke

Chambhare

Nikalje

et al. 2023

Advances in Agriculture

View full text Add to dashboard Cite

show abstract

Arginine 26 and Aspartic Acid 69 of the Regulatory Subunit are Key Residues of Subunits Interaction of Acetohydroxyacid Synthase Isozyme III from E. coli

et al. 2012

View full text Add to dashboard Cite

Acetohydroxyacid synthase (AHAS), which catalyzes the first step in the biosynthesis of branched-chain amino acids, is composed of catalytic and regulatory subunits. The enzyme exhibits full activity only when the regulatory subunit (RSU) binds to the catalytic subunit (CSU). However, the crystal structure of the holoenzyme has not been reported yet, and the molecular interaction between the CSU and RSU is also unknown. Herein, we introduced a global-surface, site-directed labeling scanning method to determine the potential interaction region of the RSU. This approach relies on the insertion of a bulky fluorescent probe at the designated site on the surface of the RSU to cause a dramatic change in holoenzyme activity by perturbing subunit interaction. Then, the key amino acid residues in the potential interaction regions were identified by site-directed mutagenesis. Compared to the wild-type, the single-point mutants R26A and D69A showed 54 and 64 % activity, respectively, whereas the double mutant (R26A+D69A) gave 14 %, thus suggesting that residues Arg26 and Asp69 are the key residues of subunit interaction with cooperative action. Additionally, the results of GST pull-down assays and pH-dependence experiments suggested that polar interaction is the main force for subunits interaction. A plausible protein-protein interaction model of the holoenzyme of Escherichia coli AHAS III is proposed, based on the mutagenesis and protein docking studies. The protocol established here should be useful for the identification of the molecular interactions between proteins.

show abstract

An easy and sensitive assay for acetohydroxyacid synthases based on the simultaneous detection of substrates and products in a single step

Engelhardt,

Ebeling,

Kaltenegger

et al. 2024

Anal Bioanal Chem

View full text Add to dashboard Cite

Acetohydroxyacid synthase (AHAS, EC 2.2.1.6) catalyzes the first step in the synthesis of the branched-chain amino acids valine, leucine, and isoleucine, pathways being present in plants and microorganisms, but not in animals. Thus, AHAS is an important target for numerous herbicides and, more recently, for the development of antimicrobial agents. The need to develop new and optimized herbicides and pharmaceuticals requires a detailed understanding of the biochemistry of AHAS. AHAS transfers an activated two-carbon moiety derived from pyruvate to either pyruvate or 2-oxobutyrate as acceptor substrates, forming 2-acetolactate or 2-acetohydroxy-2-butyrate, respectively. Various methods have been described in the literature to biochemically characterize AHAS with respect to substrate preferences, substrate specificity, or kinetic parameters. However, the simultaneous detection and quantification of substrates and unstable products of the AHAS-catalyzed reaction have always been a challenge. Using AHAS isoform II from Escherichia coli, we have developed a sensitive assay for AHAS-catalyzed reactions that uses derivatization with ethyl chloroformate to stabilize and volatilize all reactants in the aqueous solution and detect them by gas chromatography coupled to flame ionization detection or mass spectrometry. This assay allows us to characterize the product formation in reactions in single and dual substrate reactions and the substrate specificity of AHAS, and to reinterpret previous biochemical observations. This assay is not limited to the AHAS-catalyzed reactions, but should be applicable to studies of many metabolic pathways. Graphical Abstract

show abstract

Mutagenesis studies on the sensitivity of Escherichia coli acetohydroxyacid synthase II to herbicides and valine

Cited by 14 publications

References 23 publications

Improvement of Soybean Crop for Yield, Stress Tolerance, and Value-Added Products Using a Transgenic Approach

Improvement of Soybean Crop for Yield, Stress Tolerance, and Value-Added Products Using a Transgenic Approach

Arginine 26 and Aspartic Acid 69 of the Regulatory Subunit are Key Residues of Subunits Interaction of Acetohydroxyacid Synthase Isozyme III from E. coli

An easy and sensitive assay for acetohydroxyacid synthases based on the simultaneous detection of substrates and products in a single step

Contact Info

Product

Resources

About