Background: Higher plants possess several mechanisms of defense against plant pathogens. Proteins actively synthesized in response to those stresses are called defense-related proteins which, among others, include certain protease inhibitors. It is of particular relevance to investigate plant natural defense mechanisms for pathogen control which include cystatins-specific inhibitors of cysteine proteases.
Results: In this study, a cysteine proteinase inhibitor (CPI), 11 kDa in size, was purified from green kiwifruit to homogeneity. Immuno-tissue print results indicated that CPI is most abundant in the outer layer of pericarp, near the peel, and the inner most part of the pulp-sites where it could act as a natural barrier against pathogens entering the fruit. The purified protein (15 µmol L(-1)) showed antifungal activity against two phytopathogenic fungi (Alternaria radicina and Botrytis cinerea) by inhibiting fungal spore germination. In vivo, CPI (10 µmol L(-1)) was able to prevent artificial infection of apple and carrot with spore suspension of B. cinerea and A. radicina, respectively. It also exerted activity on both intracellular and fermentation fluid proteinases.
Conclusion: Identification and characterization of plant defense molecules is the first step towards creation of improved methods for pathogen control based on naturally occurring molecules.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1002/jsfa.5728 | DOI Listing |
Viruses
January 2025
Department of Biochemistry and Molecular Biotechnology, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA.
Enterovirus-D68 (EV68) continues to present as a global health issue causing respiratory illness and outbreaks associated with long-lasting neurological disease, with no antivirals or specific treatment options. The development of antiviral therapeutics, such as small-molecule inhibitors that target conserved proteins like the enteroviral 3C protease, remains to be achieved. While various 3C inhibitors have been investigated, their design does not consider the potential emergence of drug resistance mutations.
View Article and Find Full Text PDFViruses
December 2024
Scientific Research Institute for Biological Safety Problems, Ministry of Health of Kazakhstan, Almaty 080409, Kazakhstan.
The global burden of COVID-19 continues to rise, and despite significant progress in vaccine development, there remains a critical need for effective treatments for the severe inflammation and acute lung injury associated with SARS-CoV-2 infection. In this study, we explored the antiviral properties of a plant-derived complex consisting of flavonol and hydroxyorganic acid compounds. Our research focused on the ability of the flavonol and hydroxyorganic acid complex to suppress the activity of several key proteins involved in the replication and maturation of SARS-CoV-2.
View Article and Find Full Text PDFViruses
December 2024
Department of Medicine, Division of Nephrology, Hypertension, and Renal Transplantation, University of Florida College of Medicine, Gainesville, FL 32608, USA.
The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is responsible for causing the Coronavirus disease 2019 (COVID-19) outbreak. While mutations cause the emergence of new variants, the ancestral SARS-CoV-2 strain is unique among other strains. Various clinical parameters, the activity of cathepsin proteases, and the concentration of various proteins were measured in urine samples from COVID-19-negative participants and COVID-19-positive participants.
View Article and Find Full Text PDFMolecules
January 2025
Department of Chemistry, Technical University of Denmark, 206 Kemitorvet, 2800 Kgs Lyngby, Denmark.
A human epidermal growth factor receptor 2 (HER2)-specific nanobody called 2Rs15d, containing a His3LysHis6 segment at the C-terminus, was recombinantly produced. Subsequent site-selective acylation on the C-terminally activated lysine residue allowed installation of the cytotoxin monomethyl auristatin E-functionalized cathepsin B-sensitive payload to provide a highly homogenous nanobody-drug conjugate (NBC), which demonstrated high potency and selectivity for HER2-positive breast cancer models.
View Article and Find Full Text PDFMolecules
January 2025
Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Southwest Medical University, Luzhou 646000, China.
The three-year COVID-19 pandemic 'has' caused a wide range of medical, social, political, and financial implications. Since the end of 2020, various mutations and variations in SARS-CoV-2 strains, along with the immune escape phenomenon, have emerged. There is an urgent need to identify a relatively stable target for the development of universal vaccines and drugs that can effectively combat both SARS-CoV-2 strains and their mutants.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!