In Neurospora crassa, histidine starvation of histidine mutants resulted in derepression of histidine, tryptophan, and arginine biosynthetic enzymes. The same tripartite derepression occurred in wild-type strain 74A when it was grown in medium supplemented with 3-amino-1,2,4-triazole, an inhibitor of histidine biosynthesis. Histidine-mediated derepression of tryptophan and arginine biosynthetic enzymes was not due to a lowered intracellular concentration of tryptophan or arginine, respectively. A discussion of possible mechanisms and of similar studies in prokaryotic and eukaryotic organisms is presented.
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http://dx.doi.org/10.1128/jb.119.3.893-898.1974 | DOI Listing |
Physiol Plant
January 2025
Institute for Plant Biochemistry and Photosynthesis, Consejo Superior de Investigaciones Científicas, Seville, Spain.
In the context of climate changing environments, microalgae can be excellent organisms to understand molecular mechanisms that activate survival strategies under stress. Chlamydomonas reinhardtii signalling mutants are extremely useful to decipher which strategies photosynthetic organisms use to cope with changeable environments. The mutant vip1-1 has an altered profile of pyroinositol polyphosphates (PP-InsPs), which are signalling molecules present in all eukaryotes and have been connected to P signalling in other organisms including plants, but their implications in other nutrient signalling are still under evaluation.
View Article and Find Full Text PDFAntibiotics (Basel)
January 2025
Center for Targeted Drug Delivery, Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Harry and Diane Rinker Health Science Campus, Irvine, CA 92618, USA.
We have previously reported peptides composed of sequential arginine (R) residues paired with tryptophan (W) or 3,3-diphenyl-L-alanine residues (Dip), such as cyclic peptides [RW] and [R(Dip)], as antibacterial agents. Herein, we report antibacterial and antifungal activities of five linear peptides, namely ((DipR)(WR)), ((DipR)(WR)), ((DipR)(WR)), ((DipR)(WR)), and (DipR)R, and five cyclic peptides [(DipR)(WR)], [(DipR)(WR)], [(DipR)(WR)], [(DipR)(WR)], and [DipR], containing alternate positively charged R and hydrophobic W and Dip residues against fungal, Gram-positive, and Gram-negative bacterial pathogens. The minimum inhibitory concentrations (MICs) of all peptides were determined by the micro-broth dilution method against , , , , , , , , and .
View Article and Find Full Text PDFVet Med Sci
January 2025
Animal Disease Diagnosis Division, Animal and Plant Quarantine Agency (APQA), Ministry of Agriculture, Food and Rural Affairs, Gimcheon-si, Republic of Korea.
Background: Amino acid supplements are crucial for animal health and productivity. Traditional analysis methods face limitations like complexity, long testing times and toxic reagents. Therefore, a more efficient and reliable method is needed.
View Article and Find Full Text PDFFront Bioeng Biotechnol
January 2025
Department of Periodontology, School and Hospital of Stomotology, Tianjin Key Laboratory of Oral Soft and Hard Tissues Restoration and Regeneration, Tianjin Medical University, Tianjin, China.
The combination of hydrophilic arginine residues and hydrophobic tryptophan residues is considered to be the first choice for designing short-chain antimicrobial peptides (AMPs) due to their potent antibacterial activity. Based on this, we designed an arginine- and tryptophan-rich short peptide, VR-12. Peri-implantitis is a significant microbial inflammatory disorder characterized by the inflammation of the soft tissues surrounding an implant, which ultimately leads to the progressive resorption of the alveolar bone.
View Article and Find Full Text PDFAnal Chem
January 2025
Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China.
Designing single-template molecularly imprinted chiral sensors for the enantioselective recognition of various chiral amino acids (AAs) is of great importance for chiral analysis. Here, a dummy template-based chiral sensor is developed by using l-alanine (l-Ala) as the dummy template and poly(-phenylenediamine) as the imprinting layer, which can be used for the enantioselective recognition of various chiral AAs such as Ala, tryptophan (Trp), tyrosine (Tyr), cysteine (Cys), and arginine (Arg). Compared with conventional single-template molecularly imprinted chiral sensors, the designed single-template chiral sensor shows great universality for the recognition of chiral AAs since all chiral AAs possess an Ala-analogous segment.
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