Construction of 5-aminolevulinic acid synthase variants by cysteine-targeted mutation to release heme inhibition.

J Biosci Bioeng

Key Laboratory of Systems Bioengineering (Ministry of Education), Frontier Science Center for Synthetic Biology (Ministry of Education), Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China. Electronic address:

Published: November 2022

5-Aminolevulinic acid (5-ALA), a vital precursor for the biosynthesis of tetrapyrrole compounds, has been widely applied in agriculture and medicine, while extremely potential for the treatment of cancers, corona virus disease 2019 (COVID-19) and metabolic diseases in recent years. With the development of metabolic engineering and synthetic biology, the biosynthesis of 5-ALA has attracted increasing attention. 5-Aminolevulinic acid synthase (ALAS), the key enzyme for 5-ALA synthesis in the C4 pathway, is subject to stringent feedback inhibition by heme. In this work, cysteine-targeted mutation of ALAS was proposed to overcome this drawback. ALAS from Rhodopseudomonas palustris (RP-ALAS) and Rhodobacter capsulatus (RC-ALAS) were selected for mutation and eight variants were generated. Variants RP-C132A and RC-C201A increased enzyme activities and released hemin inhibition, respectively, maintaining 82.5% and 81.9% residual activities in the presence of 15 μM hemin. Moreover, the two variants exhibited higher stability than that of their corresponding wild-type enzymes. Corynebacterium glutamicum overexpressing RP-C132A and RC-C201A produced 14.0% and 21.6% higher titers of 5-ALA than the control, respectively. These results strongly suggested that variants RP-C132A and RC-C201A obtained by utilizing cysteine-targeted mutation strategy released hemin inhibition, broadening their applications in 5-ALA biosynthesis.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jbiosc.2022.07.019DOI Listing

Publication Analysis

Top Keywords

5-aminolevulinic acid
12
cysteine-targeted mutation
12
rp-c132a rc-c201a
12
acid synthase
8
variants rp-c132a
8
released hemin
8
hemin inhibition
8
variants
5
5-ala
5
construction 5-aminolevulinic
4

Similar Publications

Background: Strawberry (Fragaria × annanasa Duch.) is an important economic fruit worldwide, whose growth and development are often hindered by water deficiency. 5-Aminolevulinic acid (ALA), a natural plant growth regulator, has been suggested to mitigate the osmotic damages by promoting root water absorption, osmotic adjustment, photosynthetic capacity, and antioxidant improvement.

View Article and Find Full Text PDF

Standardisation of the radiological definition of supramaximal resection in glioblastoma.

J Clin Neurosci

January 2025

Department of Neurosurgery, The Royal Melbourne Hospital, Victoria, Australia; Department of Surgery, The University of Melbourne, Victoria, Australia. Electronic address:

Glioblastoma remains the most common and lethal primary malignant brain tumour, with high rates of recurrence and progression despite gross-total resection of the contrast-enhancing region based on T1-weighted MRI. There has been growing interest in exploring "supramaximal" resections that extend beyond contrast-enhancing borders, with initial retrospective data suggesting survival benefit, but there is currently no consensus definition. In this systematic review, we explore the evolution of supramaximal resection in glioblastoma, dissect the incongruencies in the literature regarding its definition, qualitatively appraise each definition and discuss the results of various studies that have explored its impacts on patient outcomes.

View Article and Find Full Text PDF

Manipulating stomatal aperture by silencing StSLAC1 affects potato plant-herbivore-parasitoid tritrophic interactions under drought stress.

New Phytol

January 2025

State Key Laboratory of Rice Biology, Ministry of Agricultural and Rural Affairs Key Laboratory of Molecular Biology of Crop Pathogens and Insect Pests, Institute of Insect Sciences, Zhejiang University, Hangzhou, 310058, China.

The effects of drought stress on stomatal opening dynamics, plant volatile organic compound (VOC) emissions and plant-insect interactions have been well-documented individually, but how they interact mechanistically remains poorly studied. Here, we studied how drought-triggered stomatal closure affects VOC emission and plant-trophic interactions by combining RNAi silencing, molecular biological and chemical analyses (GC-MS) of a potato-tuber moth-egg parasitoid tritrophic system. Drought stress attenuated stomatal apertures and VOC emissions, which made the potato (Solanum tuberosum L.

View Article and Find Full Text PDF

Sonodynamic therapy is an emerging therapeutic approach against brain tumours. However, the treatment scheme and ultrasound parameters have yet to be explored for clinical translation. Our study aimed to optimize ultrasound parameters for sonodynamic therapy (SDT) with 5-ALA as a sonosensitizing agent and to evaluate its therapeutic outcome on the rodent 9L gliosarcoma and the human U87 glioblastoma models.

View Article and Find Full Text PDF

This study investigated whether intravenous administration of tumor cells killed by photodynamic therapy (PDT) with 5-aminolevulinic acid (5-ALA) had antitumor effects on distal tumors. Furthermore, a novel extracorporeal blood circulating 5-ALA/PDT system was developed. 5-ALA/PDT- (low or high irradiation) or anticancer drug-treated cells were intravenously administered to rats in a glioma cancer model.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!