Antifungal Activity of Chitosan Oligomers–Amino Acid Conjugate Complexes against Fusarium culmorum in Spelt (Triticum spelta L.)

Fusarium head blight (FHB) is a complex disease of cereals caused by Fusarium species, which causes severe damages in terms of yield quality and quantity worldwide, and which produces mycotoxin contamination, posing a serious threat to public health. In the study presented herein, the antifungal activity against Fusarium culmorum of chitosan oligomers (COS)–amino acid conjugate complexes was investigated both in vitro and in vivo. The amino acids assayed were cysteine, glycine, proline and tyrosine. In vitro tests showed an enhancement of mycelial growth inhibition, with EC50 and EC90 effective concentration values ranging from 320 to 948 µg·mL−1 and from 1107 to 1407 µg·mL−1 respectively, for the conjugate complexes, as a result of the synergistic behavior between COS and the amino acids, tentatively ascribed to enhanced cell membrane damage originating from lipid peroxidation. Tests on colonies showed a maximum percentage reduction in the number of colonies at 1500 µg·mL−1 concentration, while grain tests were found to inhibit fungal growth, reducing deoxynivalenol content by 89%. The formulation that showed the best performance, i.e., the conjugate complex based on COS and tyrosine, was further investigated in a small-scale field trial with artificially inoculated spelt (Triticum spelta L.), and as a seed treatment to inhibit fungal growth in spelt seedlings. The field experiment showed that the chosen formulation induced a decrease in disease severity, with a control efficacy of 83.5%, while the seed tests showed that the treatment did not affect the percentage of germination and resulted in a lower incidence of root rot caused by the pathogen, albeit with a lower control efficacy (50%). Consequently, the reported conjugate complexes hold enough promise for crop protection applications to deserve further examination in larger field trials, with other Fusarium spp. pathogens and/or Triticum species.

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On the Applicability of Chitosan Oligomers-Amino Acid Conjugate Complexes as Eco-Friendly Fungicides against Grapevine Trunk Pathogens

Agronomy ◽

10.3390/agronomy11020324 ◽

2021 ◽

Vol 11 (2) ◽

pp. 324

Author(s):

Laura Buzón-Durán ◽

Natalia Langa-Lomba ◽

Vicente González-García ◽

José Casanova-Gascón ◽

Jesús Martín-Gil ◽

...

Keyword(s):

Amino Acid ◽

Wood Decay ◽

Field Trials ◽

Fungal Species ◽

In Vitro Tests ◽

In Planta ◽

Management Culture ◽

Amino Acid Conjugate ◽

Acid Conjugate

In a context in which the incidence and severity of grapevine fungal diseases is increasing as a result of both climate change and modern management culture practices, reducing the excessive use of phytosanitary products in viticulture represents a major challenge. Specifically, grapevine trunk diseases (GTDs), caused by several complexes of wood decay or xylem-inhabiting fungi, pose a major challenge to vineyard sustainability. In this study, the efficacy of chitosan oligomers (COS)–amino acid conjugate complexes against three fungal species belonging to the Botryosphaeriaceae family (Neofusicoccum parvum, Diplodia seriata, and Botryosphaeria dothidea) was investigated both in vitro and in planta. In vitro tests led to EC50 and EC90 effective concentrations in the 254.6−448.5 and 672.1−1498.5 µg·mL−1 range, respectively, depending on the amino acid involved in the conjugate complex (viz. cysteine, glycine, proline or tyrosine) and on the pathogen assayed. A synergistic effect between COS and the amino acids was observed against D. seriata and B. dothidea (synergy factors of up to 2.5 and 2.8, respectively, according to Wadley’s method). The formulations based on COS and on the conjugate complex that showed the best inhibition rates, COS−tyrosine, were further investigated in a greenhouse trial on grafted vines of two varieties (”Tempranillo” on 775P and “Garnacha” on 110R rootstock), artificially inoculated with the mentioned three Botryosphaeriaceae species. The in planta bioassay revealed that the chosen formulations induced a significant decrease in disease severity against N. parvum and B. dothidea. In summary, the reported conjugate complexes may be promising enough to be worthy of additional examination in larger field trials.

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ANTIFUNGAL ACTIVITY OF SOME AMINO ACIDS COMPLEXES AGAINST CANDIDA ALBICANS

Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca Agriculture ◽

10.15835/buasvmcn-agr:1599 ◽

1970 ◽

Vol 62 ◽

Author(s):

Cornelia Braicu ◽

Andeea Stanila ◽

Ancuta Mihaela Rotar ◽

Mariana Petran ◽

Carmen Socaciu

Keyword(s):

Amino Acids ◽

Candida Albicans ◽

Amino Acid ◽

Antifungal Activity ◽

Antifungal Agent ◽

Antibacterial Agents ◽

Antifungal Agents ◽

Proliferation Rate ◽

End Points

The development of antifungal agents has lagged behind that of antibacterial agents, because fungi generally grow slowly and often in multicellular forms, they are more difficult to quantify than bacteria. This experiment was designed to evaluate the in vitro properties of the amino acids complexes as potential antifungal agent. We tested 4 amino acid complexes: Cu-lysine, Cu-methionine, Co-lysine and Co-methionine, at different concentrations. The end-points for cytotoxicity evaluation are: proliferation rate, lactate dehidrogenase activity (LDH). These two end-points gave similar results with the proliferation rate but the last methods seem to be more sensible. Cupper complexes especially those with methionine proved to have the higher activity against Candida albicans from all the amino acids complexes.

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FRUCTOSE-AMINO ACIDS IN LIVER: STIMULI OF AMINO ACID INCORPORATION IN VITRO

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)66021-1 ◽

1955 ◽

Vol 215 (1) ◽

pp. 111-124 ◽

Cited By ~ 3

Author(s):

Henry Borsook ◽

Adolph Abrams ◽

Peter H. Lowy

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Amino Acid Incorporation ◽

Acid Incorporation

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Transdermal Delivery Systems for Ibuprofen and Ibuprofen Modified with Amino Acids Alkyl Esters Based on Bacterial Cellulose

International Journal of Molecular Sciences ◽

10.3390/ijms22126252 ◽

2021 ◽

Vol 22 (12) ◽

pp. 6252

Author(s):

Paula Ossowicz-Rupniewska ◽

Rafał Rakoczy ◽

Anna Nowak ◽

Maciej Konopacki ◽

Joanna Klebeko ◽

...

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Bacterial Cellulose ◽

Acid Ester ◽

Active Pharmaceutical Ingredient ◽

Amino Acid Ester ◽

Isopropyl Ester ◽

Isopropyl Esters ◽

Transdermal Application

The potential of bacterial cellulose as a carrier for the transport of ibuprofen (a typical example of non-steroidal anti-inflammatory drugs) through the skin was investigated. Ibuprofen and its amino acid ester salts-loaded BC membranes were prepared through a simple methodology and characterized in terms of structure and morphology. Two salts of amino acid isopropyl esters were used in the research, namely L-valine isopropyl ester ibuprofenate ([ValOiPr][IBU]) and L-leucine isopropyl ester ibuprofenate ([LeuOiPr][IBU]). [LeuOiPr][IBU] is a new compound; therefore, it has been fully characterized and its identity confirmed. For all membranes obtained the surface morphology, tensile mechanical properties, active compound dissolution assays, and permeation and skin accumulation studies of API (active pharmaceutical ingredient) were determined. The obtained membranes were very homogeneous. In vitro diffusion studies with Franz cells were conducted using pig epidermal membranes, and showed that the incorporation of ibuprofen in BC membranes provided lower permeation rates to those obtained with amino acids ester salts of ibuprofen. This release profile together with the ease of application and the simple preparation and assembly of the drug-loaded membranes indicates the enormous potentialities of using BC membranes for transdermal application of ibuprofen in the form of amino acid ester salts.

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Phylogenetic analysis and predicted functional effect of protein mutations of E6 and E7 HPV16 strains isolated in Indonesia

Medical Journal of Indonesia ◽

10.13181/mji.v24i4.1197 ◽

2015 ◽

Vol 24 (4) ◽

pp. 197-205

Author(s):

Dwi Wulandari ◽

Lisnawati Rachmadi ◽

Tjahjani M. Sudiro

Keyword(s):

Amino Acids ◽

Phylogenetic Analysis ◽

Amino Acid ◽

Asian American ◽

Protein Function ◽

Single Amino Acid ◽

Hpv16 E6 ◽

E6 And E7 ◽

Neutral Mutations

Background: E6 and E7 are oncoproteins of HPV16. Natural amino acid variation in HPV16 E6 can alter its carcinogenic potential. The aim of this study was to analyze phylogenetically E6 and E7 genes and proteins of HPV16 from Indonesia and predict the effects of single amino acid substitution on protein function. This analysis could be used to reduce time, effort, and research cost as initial screening in selection of protein or isolates to be tested in vitro or in vivo.Methods: In this study, E6 and E7 gene sequences were obtained from 12 samples of Indonesian isolates, which were compared with HPV16R (prototype) and 6 standard isolates in the category of European (E), Asian (As), Asian-American (AA), African-1 (Af-1), African-2 (Af-2), and North American (NA) branch from Genbank. Bioedit v.7.0.0 was used to analyze the composition and substitution of single amino acids. Phylogenetic analysis of E6 and E7 genes and proteins was performed using Clustal X (1.81) and NJPLOT softwares. Effects of single amino acid substitutions on protein function of E6 and E7 were analysed by SNAP.Results: Java variants and isolate ui66* belonged to European branch, while the others belonged to Asian and African branches. Twelve changes of amino acids were found in E6 and one in E7 proteins. SNAP analysis showed two non neutral mutations, i.e. R10I and C63G in E6 proteins. R10I mutations were found in Af-2 genotype (AF472509) and Indonesian isolates (Af2*), while C63G mutation was found only in Af2*.Conclusion: E6 proteins of HPV16 variants were more variable than E7. SNAP analysis showed that only E6 protein of African-2 branch had functional differences compared to HPV16R.

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Synthetic Histidine-Rich Peptides Inhibit Candida Species and Other Fungi In Vitro: Role of Endocytosis and Treatment Implications

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00411-06 ◽

2006 ◽

Vol 50 (8) ◽

pp. 2797-2805 ◽

Cited By ~ 26

Author(s):

Jingsong Zhu ◽

Paul W. Luther ◽

Qixin Leng ◽

A. James Mixson

Keyword(s):

Nucleic Acid ◽

Antifungal Activity ◽

Antifungal Agents ◽

Fungal Growth ◽

Nucleic Acid Delivery ◽

Histatin 5 ◽

Ph Buffering ◽

Endosomal Acidification

ABSTRACT A family of histidine-rich peptides, histatins, is secreted by the parotid gland in mammals and exhibits marked inhibitory activity against a number of Candida species. We were particularly interested in the mechanism by which histidine-rich peptides inhibit fungal growth, because our laboratory has synthesized a variety of such peptides for drug and nucleic acid delivery. In contrast to naturally occurring peptides that are linear, peptides made on synthesizers can be varied with respect to their degrees of branching. Using this technology, we explored whether histidine-lysine (HK) polymers of different complexities and degrees of branching affect the growth of several species of Candida. Polymers with higher degrees of branching were progressively more effective against Candida albicans, with the four-branched polymer, H2K4b, most effective. Furthermore, H2K4b accumulated efficiently in C. albicans, which may indicate its ability to transport other antifungal agents intracellularly. Although H2K4b had greater antifungal activity than histatin 5, their mechanisms were similar. Toxicity in C. albicans induced by histatin 5 or branched HK peptides was markedly reduced by 4,4′-diisothiocyanato-stilbene-2,2′-disulfonate, an inhibitor of anion channels. We also determined that bafilomycin A1, an inhibitor of endosomal acidification, significantly decreased the antifungal activity of H2K4b. This suggests that the pH-buffering and subsequent endosomal-disrupting properties of histidine-rich peptides have a role in their antifungal activity. Moreover, the ability of the histidine component of these peptides to disrupt endosomes, which allows their escape from the lysosomal pathway, may explain why these peptides are both effective antifungal agents and nucleic acid delivery carriers.

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Identification in skeletal muscle of a distinct extracellular pool of amino acids, and its role in protein synthesis

Biochemical Journal ◽

10.1042/bj1210817 ◽

1971 ◽

Vol 121 (5) ◽

pp. 817-827 ◽

Cited By ~ 74

Author(s):

R. C. Hider ◽

E. B. Fern ◽

D. R. London

Keyword(s):

Skeletal Muscle ◽

Amino Acids ◽

Protein Synthesis ◽

Amino Acid ◽

Incubation Medium ◽

Extensor Digitorum Longus ◽

Extensor Digitorum ◽

Longus Muscle ◽

Kinetics Of

1. The kinetics of radioactive labelling of extra- and intra-cellular amino acid pools and protein of the extensor digitorum longus muscle were studied after incubations with radioactive amino acids in vitro. 2. The results indicated that an extracellular pool could be defined, the contents of which were different from those of the incubation medium. 3. It was concluded that amino acids from the extracellular pool, as defined in this study, were incorporated directly into protein.

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Effect of Cycloheximide on In Vitro and In Vivo Protein Synthesis by Certain Tissues of Rats and Pigeons with Special Reference to Muscle

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y73-141 ◽

1973 ◽

Vol 51 (12) ◽

pp. 933-941 ◽

Cited By ~ 2

Author(s):

Njanoor Narayanan ◽

Jacob Eapen

Keyword(s):

Amino Acids ◽

Body Weight ◽

Protein Synthesis ◽

Amino Acid ◽

Amino Acid Incorporation ◽

Contrast Administration ◽

Acid Incorporation ◽

Tissue Homogenates

The effect of cycloheximide in vitro and in vivo on the incorporation of labelled amino acids into protein by muscles, liver, kidneys, and brain of rats and pigeons was studied. In vitro incorporation of amino acids into protein by muscle microsomes, myofibrils, and myofibrillar ribosomes was not affected by cycloheximide. In contrast, administration of the antibiotic into intact animals at a concentration of 1 mg/kg body weight resulted in considerable inhibition of amino acid incorporation into protein by muscles, liver, kidneys, and brain. This inhibition was observed in all the subcellular fractions of these tissues during a period of 10–40 min after the administration of the precursor. Tissue homogenates derived from in vivo cycloheximide-treated animals did not show significant alteration in in vitro amino acid incorporation with the exception of brain, which showed a small but significant enhancement.

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The immunosuppressant FK506 inhibits amino acid import in Saccharomyces cerevisiae

Molecular and Cellular Biology ◽

10.1128/mcb.13.8.5010-5019.1993 ◽

1993 ◽

Vol 13 (8) ◽

pp. 5010-5019 ◽

Cited By ~ 1

Author(s):

J Heitman ◽

A Koller ◽

J Kunz ◽

R Henriquez ◽

A Schmidt ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Amino Acids ◽

Amino Acid ◽

Cyclosporin A ◽

Secretory Pathway ◽

Yeast Cells ◽

Amino Acid Transporters ◽

Yeast Saccharomyces Cerevisiae ◽

Eukaryotic Microorganisms

The immunosuppressants cyclosporin A, FK506, and rapamycin inhibit growth of unicellular eukaryotic microorganisms and also block activation of T lymphocytes from multicellular eukaryotes. In vitro, these compounds bind and inhibit two different types of peptidyl-prolyl cis-trans isomerases. Cyclosporin A binds cyclophilins, whereas FK506 and rapamycin bind FK506-binding proteins (FKBPs). Cyclophilins and FKBPs are ubiquitous, abundant, and targeted to multiple cellular compartments, and they may fold proteins in vivo. Previously, a 12-kDa cytoplasmic FKBP was shown to be only one of at least two FK506-sensitive targets in the yeast Saccharomyces cerevisiae. We find that a second FK506-sensitive target is required for amino acid import. Amino acid-auxotrophic yeast strains (trp1 his4 leu2) are FK506 sensitive, whereas prototrophic strains (TRP1 his4 leu2, trp1 HIS4 leu2, and trp1 his4 LEU2) are FK506 resistant. Amino acids added exogenously to the growth medium mitigate FK506 toxicity. FK506 induces GCN4 expression, which is normally induced by amino acid starvation. FK506 inhibits transport of tryptophan, histidine, and leucine into yeast cells. Lastly, several genes encoding proteins involved in amino acid import or biosynthesis confer FK506 resistance. These findings demonstrate that FK506 inhibits amino acid import in yeast cells, most likely by inhibiting amino acid transporters. Amino acid transporters are integral membrane proteins which import extracellular amino acids and constitute a protein family sharing 30 to 35% identity, including eight invariant prolines. Thus, the second FK506-sensitive target in yeast cells may be a proline isomerase that plays a role in folding amino acid transporters during transit through the secretory pathway.

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Action of growth hormone in vitro on the net uptake and incorporation into protein of amino acids in muscle from intact rabbits given protein-deficient diets

British Journal Of Nutrition ◽

10.1079/bjn19760003 ◽

1976 ◽

Vol 35 (1) ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

M. R. Turner ◽

P. J. Reeds ◽

K. A. Munday

Keyword(s):

Amino Acids ◽

Growth Hormone ◽

Protein Synthesis ◽

Amino Acid ◽

De Novo ◽

Amino Acid Uptake ◽

Acid Uptake ◽

Amino Acid Incorporation ◽

Acid Incorporation

1. Net amino acid uptake, and incorporation into protein have been measured in vitro in the presence and absence of porcine growth hormone (GH) in muscle from intact rabbits fed for 5 d on low-protein (LP), protein-free (PF) or control diets.2. In muscle from control and LP animals GH had no effect on the net amino acid uptake but stimulated amino acid incorporation into protein, although this response was less in LP animals than in control animals.3. In muscle from PF animals, GH stimulated both amino acid incorporation into protein and the net amino acid uptake, a type of response which also occurs in hypophysectomized animals. The magnitude of the effect of GH on the incorporation of amino acids into protein was reduced in muscle from PF animals.4. The effect of GH on the net amino acid uptake in PF animals was completely blocked by cycloheximide; the uptake effect of GH in these animals was dependent therefore on de novo protein synthesis.5. It is proposed that in the adult the role of growth hormone in protein metabolism is to sustain cellular protein synthesis when there is a decrease in the level of substrate amino acids, similar to that which occurs during a short-term fast or when the dietary protein intake is inadequate.

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