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Hypothesis The widespread and prolonged use of antifungal antibiotics has led to the rapid emergence of multidrug resistant Candida species that compromise current treatments. Natural and synthetic antimicrobial peptides (AMPs) offer potential alternatives but require further development to overcome some of their current drawbacks. AMPs kill pathogenic fungi by permeabilising their membranes but it remains unclear how AMPs can be designed to maximise their antifungal potency whilst minimising their toxicity to host cells. Experiments We have designed a group of short (IIKK)3 AMPs via selective terminal modifications ending up with different amphiphilicities. Their antifungal performance was assessed by minimum inhibition concentration (MICs) and dynamic killing to 4 Candida strains and Cryptococcus neoformans, and the minimum biofilm-eradicating concentrations to kill 95% of the C. albicans biofilms (BEC95). Different antifungal actions were interpreted on the basis of structural disruptions of the AMPs to small unilamellar vesicles from fluorescence leakage, Zeta potential, small angle neutron scattering (SANS) and molecular dynamics simulations (MD). Finding AMPs possess high antifungal activities against the Candida species and Cryptococcus neoformans; some of them displayed faster dynamic killing than antibiotics like amphotericin B. G(IIKK)3I-NH2 and (IIKK)3II-NH2 were particularly potent against not only planktonic microbes but also fungal biofilms with low cytotoxicity to host cells. It was found that their high selectivity and fast action were well correlated to their fast membrane lysis, evident from data measured from Zeta potential measurements, SANS and MD, and also consistent with the previously observed antibacterial and anticancer performance. These studies demonstrate the important role of colloid and interface science in further developing short, potent and biocompatible AMPs towards clinical treatments via structure design and optimization.

Fungal infections cause serious problems in many aspects of human life, in particular infections in immunocompromised patients present serious problems. Current anti-fungal antibiotics target various metabolic pathways, predominantly the cell wall or cellular membrane metabolism. Numerous compounds are available to combat fungal infections, but their efficacy is far from satisfactory and some of them display high toxicity. The emerging antibiotic resistance represents a serious issue as well. Hence, there is a considerable need for new anti-fungal compounds with lower toxicity and higher effectiveness. One of the unique anti-fungal antibiotics is sordarin, the only known compound that acts on the fungal translational machinery per se. Sordarin inhibits protein synthesis at the elongation step of the translational cycle, acting on eukaryotic translation elongation factor 2. In this review, we deliver a robust scientific platform promoting the development of anti-fungal compounds, in particular focusing on the molecular action of sordarin.

Gut fungi is known to play many important roles in human health regulations. Herein, we investigate the anti-obesity efficacy of the antifungal antibiotics (amphotericin B, fluconazole and 5-fluorocytosine) in the high fat diet-fed (HFD) mice. Supplementation of amphotericin B or fluconazole in water can effectively inhibit obesity and its related disorders, whereas 5-fluorocytosine exhibit little effects. The gut fungus Candida parapsilosis is identified as a key commensal fungus related to the diet-induced obesity by the culture-dependent method and the inoculation assay with C. parapsilosis in the fungi-free mice. In addition, the increase of free fatty acids in the gut due to the production of fungal lipases from C. parapsilosis is confirmed as one mechanism by which C. parapsilosis promotes obesity. The current study demonstrates the gut C. parapsilosis as a causal fungus for the development of diet-induced obesity in mice and highlights the therapeutic strategy targeting the gut fungi., Shanshan Sun, Li Sun, Kai Wang, et al. report that the gut commensal Candida parapsilosis is a causative fungus for the development of high fat-diet induced obesity in mice. Their results suggest that fungi could represent possible targets for combating obesity.

Background: Natamycin belongs to a large group of naturally occurring polyene antifungal antibiotics derived from Streptomyces natalensis. Natamycin has a restrictive pharmaceutical role because of its extremely low aqueous solubility, which severely reduces the bioavailability of the drug. To improve the absorption of the drug, nanocrystals of natamycin were prepared and incorporated into in situ gel. Aim: To improve the solubility and absorption of natamycin nanocrystals by preparing nanocrystal in situ gel of natamycin for ophthalmic delivery Methodology: Natamycin nanocrystal was prepared using Sono-Precipitation method. Box-Behnken approach was employed to assess the influence of independent variables, namely concentration of stabilizer, sonication time and amplitude on particle size and zeta potential of the prepared nanocrystal. Optimized natamycin nanocrystal in situ gel formulations was characterized for various parameters like pH, viscosity, drug content, in vitro drug release and ex vivo permeation studies. Results: The optimized formulation of natamycin nanocrystal with a particle size of 293.9nm and zeta potential -14.6mV was incorporated into in situ gels. The pH triggered in situ gel was prepared using Carbopol and Hydroxypropyl methylcellulose (HPMC)., which showed clear preparation, pH of the formulation was closed to the pH of tear fluid, i.e., 7.4, viscosity showed pseudoplastic behaviour with immediate gelation remained for an extended period, and the drug content was around 99.70%. From the characterizations given above, PF-4 was optimized and evaluated for In vitro drug release showing slow and sustained release when compared to the marketed formulation and followed first-order kinetics with the diffusion-controlled mechanism. Ex vivo permeation through goat's cornea of PF-4 showed better permeation than marketed formulation. The stability studies of PF-4 showed that formulation was stable at the appropriate condition. Conclusion: Nanocrystals formulations of natamycin was successfully formulated and incorporated into in situ gels. Further in vivo studies need to be carried out for confirmation of pharmacological activity

Aims Echinocandin B (ECB) is a kind of lipopeptide antifungal antibiotic, as well as the key precursor of antifungal drug Anidulafungin. Its efficient bioproduction plays an important role in promoting the industrial production of Anidulafungin. Methods and results In this study, methyl oleate and Tween 80 were firstly used to enhance the ECB fermentation by Aspergillus nidulans, the results showed that the ECB titre was significantly enhanced with the addition of methyl oleate and Tween 80. Among the lipids, methyl oleate was found to play a pivotal role in increasing the ECB titre to 2123 mg l-1 , which was more than five times higher than that of the control. The addition of Tween 80 in the medium resulted in ECB titre increased to 2584 mg l-1 . The scanning electron microscope (SEM) and N-phenyl-1-naphthylamine (NPN) assay indicated that Tween 80 could influence the cell membrane permeability of A. nidulans, and enhance the intracellular and extracellular substance exchange, therefore lead to the increasing of ECB titre. Conclusions Methyl oleate and Tween 80 are optimal carbon sources and surfactants for efficient ECB biosynthesis respectively. Significance and impact of the study Surfactant was used in ECB fermentation for the first time, which provided feasible ideas for optimizing the fermentation process of other fungi.

Objective(s): Azole antifungal agents, which are widely used as antifungal antibiotics, inhibit cytochrome P450 sterol 14α-demethylase (CYP51). Nearly all azole antifungal agents are Nsubstituted azoles. In addition, an azolylphenalkyl pharmacophore is uniquely shared by all azole antifungals. Due to the importance of nitrogen atom of azoles (N-3 of imidazole and N-4 of triazole) in coordination with heme in the binding site of the enzyme, here a group of N- un-substituted azoles in which both nitrogen are un-substituted was reported. Materials and Methods: Designed compounds were synthesized by reaction of imidazole-4-carboxaldehyde with appropriate arylamines and subsequently reduced to desired amine derivatives. Antifungal activity against Candida albicans and Saccharomyces cervisiae were done using a broth micro-dilution assay. Docking studies were done using AutoDock. Results: Antimicrobial evaluation revealed that some of these compounds exhibited moderate antimicrobial activities against tested pathogenic fungi, wherein compounds 3, 7, and 8 were potent. Docking studies propose that all of the prepared azoles interacted with 14α-DM, wherein azoleheme coordination played the main role in drug-receptor interaction. Conclusion: Our results offer some useful references for molecular design performance or modification of this series of compounds as a lead compound to discover new and potent antimicrobial agents.

In the soil gammaproteobacterium Lysobacter enzymogenes, a natural fungal predator, the response regulator PilR controls type IV pili (T4P)‐mediated twitching motility as well as synthesis of the heat‐stable antifungal factor (HSAF). Earlier we showed that PilR acts via the second messenger, c‐di‐GMP; however, the mechanism remained unknown. Here, we describe how PilR, c‐di‐GMP signalling, and HSAF synthesis are connected. We screened genes for putative diguanylate cyclases (c‐di‐GMP synthases) and found that PilR binds to the promoter region of lchD and down‐regulates its transcription. The DNA‐binding affinity of PilR, and therefore its repressor function, are enhanced by phosphorylation by its cognate histidine kinase, PilS. The lchD gene product is a diguanylate cyclase, and the decrease in LchD levels shifts the ratio of c‐di‐GMP‐bound and c‐di‐GMP‐free transcription factor Clp, a key activator of the HSAF biosynthesis operon expression. Furthermore, Clp directly interacts with LchD and enhances its diguanylate cyclase activity. Therefore, the PilS–PilR two‐component system activates T4P‐motility while simultaneously decreasing c‐di‐GMP levels and promoting HSAF production via the highly specific LchD–c‐di‐GMP–Clp pathway. Coordinated increase in motility and secretion of the “long‐distance” antifungal weapon HSAF is expected to ensure safer grazing of L. enzymogenes on soil or plant surfaces, unimpeded by fungal competitors, or to facilitate bacterial preying on killed fungal cells. This study uncovered the mechanism of coregulated pili‐based motility and production of an antifungal antibiotic in L. enzymogenes, showcased the expanded range of functions of the PilS–PilR system, and highlighted exquisite specificity in c‐di‐GMP‐mediated circuits., PilR phosphorylation mediated by PilS down‐regulates lchD expression via DNA binding to lower c‐di‐GMP synthesis and thus accumulate c‐di‐GMP‐free Clp, which activates heat‐stable antifungal factor production via DNA binding.

In this work we present a software system that enables antifungal antibiotic drug candidate toxicity and likelihood of drug binding prediction. The system is composed of a number of machine learning models and deterministic algorithms. Its implementation utilizes modern software development practices including a client-server architecture with a thin web-client. Testing showed the models’ accuracy and viability for predicting antifungal antibiotics’ properties.

Introduction.Amphotericin B remains the drug of first choice in the treatment of most severe systemic fungal infections. However, it is characterized by very low solubility and high toxicity. Amphamide – semisynthetic derivative of Amphotericin B – have been prepared at the Gause Institute of New Antibiotics. It showed several advantages over amphotericin B in vivo.Objective.The aim of the study was to investigate the toxicological safety of amphamide drug formulation in chronic experiment on rats.Materials and methods.The study was performed in male and female Wistar rats. Amphamide drug formulation was injected intraperitonealy at the total doses of MTD and LD50(30 × 0,07 mg/kg or 30 × 0,17 mg/kg with 24-h interval). During the experiment body weight, hematological parameters, blood biochemical parameters, electrocardiography and urinalysis were performed. Animals were sacrificed on 1st and 30th day after the end of treatment. At necropsy, the mass coefficients of heart, liver, kidneys, spleen and thymus were calculated. The internal organs were subjected to histological evaluation.Results.It has been shown that the treatment with total dose of amphamide produces an increase of urea and creatinine level in serum, changes in urine composition and its specific gravity. Microscopic pathology observation showed dose-dependent structure abnormalities in kidneys, liver, lungs, stomach, and testes. Multiple administration of low dose of the drug produces transient toxic effects completely reversible within 30 days. When amphamide was used in a high dose, morphological signs of toxic cardiomyopathy were found.Conclusion.The results of the clinical and laboratory studies and microscopic pathology observation of kidneys demonstrate that nephrotoxicity is the main limiting type of drug toxicity. Dose dependence and reversibility within a month of toxic effects of amphamide allows us to recommend it to further advance.

Mucormycosis is a rare, life-threatening, and opportunistic fungal infection that usually occurs in immunocompromised patients. Rhinocerebral and pulmonary manifestations are the common form. The rare form of gastrointestinal mucormycosis occur in all parts of the alimentary tract, with emphasis on the stomach being the most common site. Primary gastric mucormycosis following traumatic injury is an extremely rare form that is usually lethal; thus, only a few cases of survival have been reported even after early diagnosis and aggressive surgical resection, combined with antifungal treatment. We herein report a case of delayed-onset gastric mucormycosis in a polytrauma patient without predisposing factors, which was successfully treated by antifungal medical therapy alone with no surgical debridement.

Lysobacter enzymogenes is a non-flagellated, soil proteobacterium that secretes a diffusible antibiotic known as heat-stable antifungal factor (HSAF) to kill nearby fungi for food. The genome of the model strain OH11 encodes a homologous Wsp system, which is generally deployed by flagellated bacteria to achieve flagella-dependent outputs via a c-di-GMP-FleQ complex, in which c-di-GMP is a ubiquitous dinucleotide second messenger and FleQ is a transcription factor (TF). Here, we show that the Wsp system in the non-flagellated OH11 participates in a unique c-di-GMP-dependent signalling pathway and forms a WspR-CdgL binary complex to alter HSAF production, in which WspR and CdgL act as a c-di-GMP diguanylate cyclase (DGC) and a non-TF binding protein respectively. We found that the phosphorylation of WspR activates its DGC activity and enhances c-di-GMP production while inhibiting HSAF biosynthesis. The phosphorylation of WspR also plays a key role in weakening WspR-CdgL binding and HSAF generation. Interestingly, c-di-GMP binding to CdgL did not seem to induce the disassociation of the WspR-CdgL complex. These observations, along with our earlier findings, lead us to propose a model in which L. enzymogenes re-programs the Wsp system via c-di-GMP signalling to regulate HSAF biosynthesis for the benefit of ecological adaptation.

Microwave (MW) assisted synthetic technique was applied for the preparation of chalcone derivatives 5-7 employing Claisen-Schmidt condensation between 2-hydroxyacetophenone and aromatic aldehydes. These chalcones were further subjected to oxidative cyclization via MW irradiation and furnished the related flavones 8-10 which were characterized by FT-IR, 1H and 13CNMR spectra. The use of these MW assisted reactions provided higher productivity (92-98%) in shorter reaction time (2-6 min) with eco-friendly mild reaction conditions and hence found to be a convenient method as compared to conventional synthesis. These chalcones 5-7, and flavones 8-10 were screened for in vitro antimicrobial activities against five bacterial and three fungal pathogens. The study indicated that they were more active against fungal pathogens than that of bacterial organisms and comparable to the standard antifungal antibiotic nystatin. Interestingly, the prediction of activity spectra for substances (PASS) was also found in agreement with the in vitro results. Some of the compounds were found to have good ADMET properties.

Small molecules are able to regulate numerous cellular processes through binding to various bacterial receptor proteins, but the mechanisms and functions by which these chemicals coordinate and execute remain poorly understood. 4-hydroxybenzoic acid (4-HBA) and cyclic di-GMP (c-di-GMP) are two such molecules with distinct structures that are produced in Lysobacter enzymogenes to synergistically affect the secretion of an antifungal antibiotic, known as heat-stable antifungal factor (HSAF). In our earlier studies, we showed that CdgL, a YajQ-like protein without DNA-binding domain, was able to physically interact with LysR, a transcription factor, to enhance its binding affinity toward the upstream region of the HSAF biosynthesis operon promoter, hence increasing the HSAF biosynthesis. Interestingly, 4-HBA or c-di-GMP can bind to its cognate receptor of LysR or CdgL, respectively, to regulate the HSAF biosynthesis. Further, c-di-GMP acts by binding to CdgL to induce the dissociation of the CdgL-LysR complex, leading to decreased downstream expression. We now showed that CdgL controlled the transcription of lenB2, which encodes an oxygenase to convert chorismate to 4-HBA. Notably, overexpression of cdgL was found to stimulate lenB2 transcription, which likely increased the intracellular 4-HBA content. Also, 4-HBA could bind to LysR to interrupt the LysR-CdgL complex formation and release of CdgL, which caused a lower affinity of LysR toward DNA and hence decreased HSAF operon expression. These findings, along with our earlier report, allow us to propose a coordination mechanism demonstrating how the HSAF biosynthesis is co-regulated by 4-HBA and c-di-GMP through interactions with their cognate receptors. This new mechanism shall shed light on improving the HSAF yield for practical usage.

The pharmacokinetics of amphamide, a new semisynthetic antifungal antibiotic, are studied after intravenous injection to rats and rabbits. The amphamide concentration in biological samples was determined by HPLC. Amphamide pharmacokinetics in rabbits were nonlinear. Amphamide levels in animal blood plasma decreased in a triphasic manner. The total clearance and steady-state distribution volume were greater in rats than in rabbits (0.85 vs. 0.3 – 0.5 mL ∙ min–1 ∙ kg–1 and 1.5 vs. 0.6 – 0.9 L/kg, respectively). The mean residence times of amphamide in rats and rabbits were similar (30 vs. 27 – 43 h, respectively). The elimination half-lives calculated using a three-compartment model were 24 h for rats and 31 h for rabbits. The availability of rat tissue for amphamide ranged from 100% (brain) to 1700% (kidneys).

Candida albicans is currently the fourth-leading cause of hospital-acquired bloodstream infections, reaching a mortality rate of up to 35–40% for systemic or disseminated infections. Systemic mycoses can occur in patients with severely impaired immune systems (AIDS), with organ or bone marrow transplants, cancer patients undergoing chemotherapy, and patients in ICU (neonates and elderly). It is, therefore, obvious that there is a substantial need for fast, effective antifungal antibiotics to combat fungal infections. The present investigation has been proposed to screen effective fungal metabolites for the control of Candida albicans by evaluating the potential of fungal bioactive compounds, its purification and characterization

Heat-stable antifungal factor (HSAF) is a broad-spectrum antifungal antibiotic produced by the biological control agent, Lysobacter enzymogenes. In our earlier works, we have applied HSAF to effectively control wheat and pear fungal disease. However, a major bottleneck in its practical application is the low HSAF production level; therefore, boosting its production is essential for its wide application. In the past, we find that c-di-GMP, a universal bacterial second messenger, is inhibitory to HSAF production. In this work, we further identified eight active diguanylate cyclases (DGCs) responsible for c-di-GMP synthesis in Lysobacter enzymogenes via both bioinformatics and genetic analyses. We generated a strain lacking seven active DGC genes and found that this DGC-modified strain, OH11LC, produced a higher HSAF amount in a c-di-GMP concentration-dependent manner. Subsequently, by employing OH11LC as the host fermentation strain, we could even produce a much higher HSAF amount (> 200-fold). After improving the HSAF production, we further developed a technique of seed coating method with HSAF, which turned out to be effective in fighting against the maize seed-borne filamentous pathogen, Pythium gramineacola. Overall, via combining strain modification and fermentation optimization, we demonstrated a good example of translating fundamental knowledge of bacterial c-di-GMP signaling into biological control application in which we relieved the inhibitory effect of c-di-GMP on HSAF biosynthesis by deleting a bunch of potentially active L. enzymogenes DGC genes to improve HSAF yield and to expand its usage in antifungal seed coating.

(1,3)-β-D-Glucan synthase (GS) catalyzes formation of the linear (1,3)-β-D-glucan in the fungal cell wall, and is a target of clinically approved antifungal antibiotics. The catalytic subunit of GS, FKS protein, does not exhibit significant sequence homologies to other glycosyltransferases, and thus a significant ambiguity remains about its catalytic mechanism. One of the major technical barriers in studying GS is the absence of activity assay methods that allow characterization of the lengths and amounts of (1,3)-β-D-glucan due to its poor solubility in water and organic solvents. Here, we report a successful development of a novel GS activity assay based on size-exclusion chromatography coupled with pulsed-amperometric detection and radiation counting (SEC-PAD-RC), which allows for the simultaneous characterization of the amount and length of the polymer product. The assay revealed that the purified yeast GS produces glucan with a length of 6,550 ± 760 mer, consistent with the reported degree of polymerization of (1,3)-β-D-glucan isolated from intact cells. Pre-steady state kinetics analysis revealed a highly efficient but rate-determining chain elongation rate of 51.5 ± 9.8 sec(−1), which represents the first observation of chain elongation by a nucleotide-sugar dependent polysaccharide synthase. Coupling the SEC-PAD-RC method with substrate analog mechanistic probes provided the first unambiguous evidence that GS catalyzes non-reducing end polymerization. Based on these observations, we propose a detailed model for the catalytic mechanism of GS. The approaches described here can be used to determine the mechanism of catalysis of other polysaccharide synthases.

Honeys originating from Sidr (Ziziphus spina‐christi L.) and Talh (Acacia gerrardii Benth.) trees in Saudi Arabia exhibited substantial antimicrobial activity against pathogenic gram‐positive bacteria (Bacillus cereus, Staphylococcus aureus), gram‐negative bacteria (Escherichia coli, Salmonella enteritidis), and a dermatophytic fungus (Trichophyton mentagrophytes). The diameter of zones of inhibition represents the level of antimicrobial potency of the honey samples. Precisely, Talh honey showed significantly higher antibacterial activity against all tested bacteria than Sidr honey. The antifungal activity of Talh and Sidr honey types was significantly at par against a dermatophytic fungus. The water‐diluted honey types (33% w/v) significantly induced a rise in the antimicrobial activity from that of the natural nondiluted honeys. Microbial strains displayed differential sensitivity; gram‐positive bacteria were more sensitive and presented larger inhibition zones than gram‐negative bacteria and the fungus. The sensitivity was highest in B. cereus and S. aureus, followed by T. mentagrophytes, E. coli, and S. enteritidis. The antimicrobial activity of water‐diluted honeys (Sidr and Talh) was high than that of broad‐spectrum antibacterial antibiotics (tetracycline and chloramphenicol) against bacterial strains, but these honeys were relativity less potent than antifungal antibiotics (flucoral and mycosat) against a fungal strain. Our findings indicate the antimicrobial potential of Saudi honeys to be considered in honey standards, and their therapeutic use as medical‐grade honeys needs further investigations.

Background: Cancer is the second leading cause of death globally. Hydrazone and hydrazone derivatives have high activity, and for this reason, these compound are greatly used by researchers to synthesize new anti-cancer drug. The aim of this research work is to synthesize novel anticancer agents. Methods: New hydrazone derivatives were synthesized via a reaction between 3-formylphenyl methyl carbonate and benzhydrazide, 4-methylbenzoic hydrazide, 4-tert-butylbenzoic hydrazide, 4-nitrobenzoic hydrazide and 3- methoxybenzoic hydrazide, and were successfully characterized using elemental analysis, 1H-NMR, 13C-NMR, FT-IR and LC-MS techniques. The synthesized compounds were evaluated for their antimicrobial (some grampositive and -negative bacteria, filamentous fungi and yeasts), anti-proliferative (T47D and HCC1428-breast cancer cells) and anti-angiogenic (HUVEC-endothelial cells) activities. The anti-proliferative activities of the hydrazone compounds R1-R5 were studied on these cell lines by MTT assay. The anti-angiogenic potential of the compounds was determined by the endothelial tube formation assay. To identify structural features related to the anti-proliferative activity of these compounds, 2D-QSAR was performed. Results: The results indicated that compound R3 exhibited strong anti-angiogenic and anti-proliferative activity on breast cancer cell lines and healthy cell lines. Also, this compound; possessing a tertiary butyl moiety on the hydrazine, exhibited the highest inhibitory effect against all tested microorganisms; in particular, it inhibited Candida albicans at a lower concentration than ketoconazole. Among the investigated compounds, those bearing methyl, tertiary butyl (compound R2, R3) and methoxy (compound R5) moiety were found to be more successful anticandidal derivatives than standard antifungal antibiotics. The QSAR analysis suggested that the tumor specificity of the hydrazone correlated with their molecular weight, lipophilicity, molar refractivity, water solubility, DipolHybrid:(MOPAC) and ExchangeEnergy:(MOPAC). Absorption, Distribution, Metabolism and Elimination (ADME) analysis of the hydrazone compounds showed that they have favorable pharmacokinetic and drug-likeness properties. The ADME results clarify that R3 is the best compound in terms of pharmacokinetic properties. In contrast to other compounds; target prediction analysis of the compound R3 showed inhibitory activity on estrogen-related receptor alpha transcription factor (ESRRA). The target prediction analysis was supported by molinspiration bioactivity score. Conclusion: The R3 compound is considered to be an important candidate for future studies with its suitability for the Lipinski’s rule of five for drug-likeness, and effective in vitro and in silico results.

Echinocandin B deacylase (EBDA), from Actinoplanes utahensis ZJB-08196, is capable of cleaving the linoleoyl group from echinocandin B (ECB), forming the echinocandin B nucleus (ECBN), which is a key precursor of semisynthetic antifungal antibiotics. In the present study, molecular evolution of AuEBDA by random mutagenesis combined with site-directed mutagenesis (SDM) and screening was performed. Random mutagenesis on the wild-type (WT) AuEBDA generated two beneficial substitutions of G287Q, R527V. The "best" variant AuEBDA-G287Q/R527V was obtained by combining G287Q with R527V through SDM, which was most active at 35 °C, pH 7.5, with Km and vmax values of 0.68 mM and 395.26 U/mg, respectively. Mutation of G287Q/R527V markedly increased the catalytic efficiency kcat/Km by 290% compared with the WT-AuEBDA.

Resume— Cet article est une revue des antifongiques systemiques communement utilises. Sont presentes les origines des diverses substances, leur pharmacocinetique, leur mode d'action, leurs effets secondaires et enfin, leurs indications en medecine veterinaire. [Hill, P.B., Moriello, K.A., Shaw, S.E. A review of systemic antifungal agents (Antifongiques systemiques: une revue). Abstract— This paper is a review of commonly used systemic antifungal antibiotics. Included is a review of the origins of the drugs, pharmacokinetics, modes of action, adverse effects and clinical uses in veterinary medicine.

A biologically active microbial strain, designated as “LS462,” was isolated from a soil sample collected from Yaoli Virgin Forest of Jiangxi Province, China. The strain was able to produce a high yield of echinomycin (172 mg/l) even under nonoptimized culture conditions and is proposed to serve as a promising source of echinomycin. In this study, echinomycin exhibited strong anti-Mycobacterium tuberculosis H37Rv activity and synergistic antifungal effect with a greatly reduced dosage of posaconazole on Candida albicans SC5314. The strain belongs to the genus Streptomyces according to its morphological and 16S rDNA phylogenetic analysis. The 16S rDNA was found to have the highest sequence identity with Streptomyces fuscichromogenes (99.37% similarity). Extensive nuclear magnetic resonance and mass spectroscopic data were used to determine the structure of echinomycin. The strain S. fuscichromogenes has not been previously reported to produce echinomycin. Strain LS462 may be exploited as a new potential source for the commercial production of echinomycin. Also, this work is the first to report the new synergistic antifungal activity of echinomycin and further study of the synergistic mechanism will be helpful to guide the development of antifungal agents.

Three aromatic heptaene macrolide antifungal antibiotics, Candicidin D, Partricin A (Gedamycin) and Partricin B (Vacidin) were subjected to controlled cis-trans→ all trans photochemical isomerization. The obtained all-trans isomers demonstrated substantially improved in vitro selective toxicity in the Candida albicans cells: human erythrocytes model. This effect was mainly due to the diminished hemotoxicity. The molecular modeling studies on interactions between original antibiotics and their photoisomers with ergosterol and cholesterol revealed some difference in free energy profiles of formation of binary antibiotic/sterol complexes in respective membrane environments. Moreover, different geometries of heptaene: sterol complexes and variations in polyene macrolide molecule alignment in cholesterol-and ergosterol-containing membranes were found. None of these effects are of the crucial importance for the observed improvement of selective toxicity of aromatic heptaene antifungals but each seems to provide a partial contribution.

Background: The widespread use of antibiotics has resulted in a high incidence of antibiotic-associated diarrhea (AAD); moreover, the AAD-associated mortality rates have also increased. The effect of combined antibiotic administration on AAD in critically ill patients was analyzed to assist in antibiotic selection for AAD prevention. Methods: Clinical data of patients hospitalized were retrospectively analyzed. Patients were either assigned to the combined-use group (CG) or the monotherapy group (MG). Age, sex, albumin levels, proton pump inhibitors, the type antibiotics, occurrence of AAD were collected. All relevant data were analyzed using SPSS version 18.0 (IBM Inc., Armonk, NY, USA), and significance was set at P

Series of semi-synthetic polyene macrolide antibiotics (PMAs) that were prepared by chemical modification in original research by the authors are reviewed. Chemical modification, in particular phosphorylation, was shown to produce highly efficacious PMAs with low toxicities and extended spectra of biological activity. The prospects of using liposomal and nano-derivatives of these antifungal antibiotics are discussed. Crucial issues related to the resistance of pathogenic fungi and the expanding distribution of invasive mycoses are identified. Semi-synthetic PMAs are shown to be highly effective at preventing and treating invasive mycoses and opportunistic fungal infections occurring in AIDS patients. Special attention is paid to structure—activity relationships for the semi-synthetic PMAs. Possible mechanisms of action of these compounds on pathogenic fungi are discussed. An automated intellectual information system was developed for selecting the optimal conditions for development, synthesis, and application in medical practice of new PMAs.

An increase in the number of severe candidiasis, the growing incidence of antimicrobial resistance of the pathogens responsible for these infections, as well as their harmful side effects, necessitate developing new and more effective antifungal agents. In this context, the elaboration and utilization of functional fermented milk products with microorganisms harbouring antifungal activity and thus promoting the elimination of opportunistic Candida yeasts from the body, could be of great interest. The microbiota of Kazakh national sour-milk beverages derived from mare's and camel's milk has a multidirectional health effect on the human body, but the antagonistic activity of members of these microbiota against yeast species responsible for candidiasis have not yet been studied. The aim of this work was to isolate microorganisms, with antagonistic activity against Candida yeast species from Kazakh national fermented milk beverages. The study of antagonistic activities of various dairy products of local (both domestic and commercial) production against C. albicans using well-diffusion assays showed effective suppression of yeast growth with homemade koumiss samples. Associations of microorganisms from various koumiss samples also showed antagonistic activities after performing successive inoculations and fermentations of cow's milk and whey. When cultured in cow's milk, these associations had an increased activity against C. krusei 25. The highest antagonistic activity against C. glabrata 589 was found for three associations cultured in whey. After plating the most promising associations on MRS media, 41 bacteria with were isolated from selected associations based on their colony morphotype, 28 of which were lactic acid bacteria, while the other were presumptive acetic bacteria. Thirty-four yeast isolates were also selected. In the present study, autochthonous strains of microorganisms that inhibited Candida spp. growth, including Candida strains exhibiting a high resistance to both lactic acid bacteria metabolites (intestinal and vaginal isolates of C. albicans) and antifungal antibiotic fluconazole (C. glabrata 589 and S. krusei 25), were selected for the first time. The isolated microorganisms will be used to create consortia and apply as starters to develop new functional beverages with antifungal activity against opportunistic Candida yeast species. Key words/phrases: koumiss, lactic acid bacteria, Candida yeast antagonists.

Background: India is facing a gruesome epidemic-like scenario of chronic, extensive and recalcitrant dermatophytosis for the past 5-6 years. Dermatophytosis, also commonly known as tinea, used to be considered as trivial infection and was easy to treat. Unethical and irrational mixing of antibacterial and topical corticosteroid with antifungal agents has been instrumental for this extremely challenging situation. Applying such topical preparations for the treatment of dermatophytosis, without any oral antifungal agents can result in extensive lesions and also, fungal resistance. Objective: To find out the cause and dermatophyte species associated with the extensive lesions of tinea corporis. Patients and methods: A study was carried out in the tertiary care centre by the Department of Dermatology and Microbiology during the period starting from October 2016 to April 2017. A total of 158 patients were consented. Any patient with clinical findings of Tinea corporis and KOH and/or culture positive was enrolled in the study. A detailed history was taken. Samples were collected after cleaning the part with 70% alcohol and all KOH positive or negative samples were inoculated on Sabouraud’s dextrose agar supplemented with chloramphenicol and cycloheximide. The culture plates were incubated at 25°C and were observed for four weeks. Lacto Phenol Cotton Blue (LPCB) mounts were prepared to study the microscopic structures in detail. Other tests like urease and in vitro hair perforation tests were also set up to differentiate Trichophyton interdigitale from Trichophyton rubrum. Results: A total of 149(94.30%) were KOH and 158 (100%) were culture positive. We isolated only Trichophyton interdigitale from 158 patients. None of the patients was HIV positive, 6patients (4%) had diabetes. About 70% of the patients gave history of using various combinations of antifungal, antibiotic and topical steroid creams and nearly 10% used pure steroid creams. Rest did not know the name of the cream they applied. Limitations: Molecular characterization was not done to see genetic relatedness. Conclusion: Topical steroid lowers the local immunity and contribute to the extensive and atypical lesions. Dermatophytosis has acquired epidemic proportions in this region of western UP. Misuse of unregulated combinations of steroid is rampant in this region.

В обзорной статье обобщены результаты исследований авторов, касающиеся получения целого ряда полусинтетических производных полиеновых макролидных антибиотиков с помощью химической модификации. Показано, что химическая модификация, и в частности фосфорилирование, приводит к получению малотоксичных высокоэффективных производных полиеновых макролидных антибиотиков с расширенным спектром биологического действия. Обсуждены перспективы использования липосомальных производных и нанопроизводных этих антифунгальных антибиотиков. Рассмотрены актуальные вопросы, связанные с резистентностью патогенных грибковых микроорганизмов, возрастающим распространением инвазивных микозов. Показана высокая эффективность полусинтетических производных полиеновых макролидных антибиотиков для предотвращения и лечения инвазивных микозов и оппортунистических грибковых инфекций, возникающих у больных СПИД. Особое внимание уделено анализу взаимосвязи между структурой полусинтетических производных полиеновых макролидных антибиотиков и их биологической активностью, а также обсуждению возможных механизмов действия этих соединений на патогенные грибковые микроорганизмы. Разработана интеллектуальная автоматизированная информационная система для оптимального выбора условий разработки, синтеза и применения в медицинской практике новых производных полиеновых макролидных антибиотиков.

The influence of aryl-substituted xylose derivatives on fermentation of nonmedical antifungal antibiotic imbricin was evaluated. It was shown that, though unsuitable as additional carbohydrate sources in the growth medium for microorganism-producer development, these compounds can be used as biosynthesis regulators stimulating the antibiotic production. Biological tests showed that the aryl-substituted xylose derivatives possess antibacterial activity and, when added to the initial fermentation medium, protect the imbricin fermentation process against possible contamination.

Background The polyene macrocyclic compound amphotericin B (AmB) is an important antifungal antibiotic for the clinical treatment of invasive fungal infections. To rationally guide the improvement of AmB production in the main producing strain Streptomyces nodosus, comparative metabolomics analysis was performed to investigate the intracellular metabolic changes in wild-type S. nodosus ZJB20140315 with low-yield AmB production and mutant S. nodosus ZJB2016050 with high-yield AmB production, the latter of which reached industrial criteria on a pilot scale. Results To investigate the relationship of intracellular metabolites, 7758 metabolites were identified in mutant S. nodosus and wildtype S. nodosus via LC–MS. Through analysis of metabolism, the level of 26 key metabolites that involved in carbon metabolism, fatty acids metabolism, amino acids metabolism, purine metabolism, folate biosynthesis and one carbon pool by folate were much higher in mutant S. nodosus. The enrichment of relevant metabolic pathways by gene overexpression strategy confirmed that one carbon pool by folate was the key metabolic pathway. Meanwhile, a recombinant strain with gene metH (methionine synthase) overexpressed showed 5.03 g/L AmB production within 120 h fermentation, which is 26.4% higher than that of the mutant strain. Conclusions These results demonstrated that comparative metabolomics analysis was an effective approach for the improvement of AmB production and could be applied for other industrially or clinically important compounds as well.

Exploration of endophytic bacteria with multiple plant growth promoting (PGP) attributes is considered as an eco-friendly and cost-effective alternative to agricultural chemicals for increasing crop productivity. In the present endeavor, healthy chickpea plants (Cicer arietinum L.) collected from district Birbhum, West Bengal, India were subjected for the isolation of endophytic bacteria having multifarious PGP properties. One potent endophytic Gram positive bacterial strain CNE6 was isolated from the nodule of chickpea and was identified as Bacillus siamensis based on 16S rDNA sequence homologies. The isolate showed a number of PGP properties like phosphate solubilization, IAA production, nitrogen fixation, hydroxamate type of siderophore production and ACC deaminase activities. The isolate CNE6 produced 33.27 ± 2.16 μg/mL of IAA in the presence of tryptophan. Production of IAA was also confirmed by HPLC analysis and it was found effective for inducing lateral root branching in chickpea. In addition, the isolate displayed significant antagonistic activity against a number of plant pathogenic fungi when tested by dual culture overlay and agar well diffusion assay. 50 % cell free supernatant of CNE6 was found effective for 60–80 % inhibition of radial growth of pathogenic fungi tested. Scanning electron microscopic observation revealed massive degradation of pathogenic fungal mycelia by the antifungal metabolites of CNE6. LC–MS analysis of bacterial lipopeptides suggested the production of antifungal antibiotics like surfactin, fengycin and iturin by the isolate. The presence of genes encoding antifungal lipopeptides was also confirmed by PCR amplification using specific primers. Green fluorescent protein (GFP) tagging of CNE6 using broad host range plasmid vector (pDSK-GFPuv) followed by colonization study indicated very good host colonization potential of the isolate and its probable movement through xylem vessels. Enhanced shoot and root length and chlorophyll content upon treatment with CNE6 as observed in in vivo pot experiments also supported the positive role of the endophytic isolate on overall development and growth of the chickpea plants. This is the first report of Bacillus siamensis as an endophyte of Cicer arietinum L. which can be successfully applied for improving the productivity of this crop plant.

Various fungal diseases are responsible for significant losses in harvested fruits and vegetables. Traditionally, synthetic fungicides are primarily used to control postharvest spoilage losses. Among the suggested several eco-friendly alternatives, biological control of postharvest diseases of fruits using antagonistic microorganisms has been explored as one of the many promising substitute to chemical fungicides. Prospective of several microbial antagonists, isolated from a diversity of sources, including fruit surfaces, the phyllosphere, different soils, and sea water in postharvest disease suppression has been investigated. Several modes of action have been proposed for their fungistatic activities including competition for nutrients and space, mycoparasitism, secretion of antifungal antibiotics and volatile metabolites, and induction of host resistance. Compared to preharvest use, postharvest applications of microbial antagonists are more successful in efficient disease control. Attempts have also been made to improve their overall efficacy by combining them with various salt and food additives, surfactants, physical treatments like hot water dips, UV irradiation, and modified atmosphere storage, etc. The present chapter gives an overview on use of microbial antagonists as postharvest biocontrol agents and summarizes information on their source of isolation, mechanisms of action, application methods, efficacy enhancement, product formulation, and commercialization with future area of research.

(1,3)-β-d-Glucan synthase (GS) is an essential enzyme for fungal cell wall biosynthesis that catalyzes the synthesis of (1,3)-β-d-glucan, a major and vital component of the cell wall. GS is a proven target of antifungal antibiotics including FDA-approved echinocandin derivatives; however, the function and mechanism of GS remain largely uncharacterized due to the absence of informative activity assays. Previously, a radioactive assay and reducing end modification have been used to characterize GS activity. The radioactive assay determines only the total amount of glucan formed through glucose incorporation and does not report the length of the polymers produced. The glucan length has been characterized by reducing end modification, but this method is unsuitable for mechanistic studies due to the very high detection limit of millimolar amounts and the labor intensiveness of the technique. Consequently, fundamental aspects of GS catalysis, such as the polymer length specificity, remain ambiguous. We have developed a size exclusion chromatography (SEC)-based method that allows detailed functional and mechanistic characterization of GS. The approach harnesses the pH-dependent solubility of (1,3)-β-d-glucan, where (1,3)-β-d-glucan forms water-soluble random coils under basic pH conditions, and can be analyzed by SEC using pulsed amperometric detection (PAD) and radioactivity counting (RC). This approach allows quantitative characterization of the total amount and length of glucan produced by GS with minimal workup and a d-glucose (Glc) detection limit of ~100 pmol. Consequently, this approach was successfully used for the kinetic characterization of GS, providing the first detailed mechanistic insight into GS catalysis. Due to its sensitivity, the assay is applicable to the characterization of GS from any fungi and can be adapted to study other polysaccharide synthases.

Ethnopharmacological relevance Artemisia annua L. is a traditional Chinese medicine used for the treatment of malaria, jaundice and intense fever. Aim of the study The aim of the present study was to investigate the phytochemicals, antioxidants, antimicrobial and synergistic potential of methanolic and petroleum ether extracts of A. annua against bacterial and fungal pathogens. Method Antioxidant activity of different concentrations of methanolic and petroleum ether extracts of A. annua was determined by DPPH free radical scavenging assay. Antimicrobial activity was determined by agar well diffusion, whereas MIC and synergistic activity was done by broth dilution method.TLC and GC-MS were done to identify active phytocompounds present in methanolic and petroleum ether extracts. Results Methanolic extract of A. annua showed higher antioxidant potential (IC50 37 0.75 ± 0.34 μg ml−1) as compared to petroleum ether extract. In antimicrobial analysis, methanolic and petroleum ether extracts of A. annua produced potent inhibitory activity against Candida strains as compared to bacterial strains. Methanolic and petroleum ether extracts of A. annua produced synergistic potential with decrease in MIC from 4 to 264 folds against bacterial (S. aureus and E. coli) and Candida strains in combination with antibacterial and antifungal antibiotics. Sub fraction I of methanolic and petroleum ether extracts was isolated through silica TLC and showed 10-fold more antimicrobial activity as compared to crude extract. GC-MS analysis of sub-fraction I of A. annua revealed 13 major phytocompounds with area more than 1%. Interestingly, 2-Propenoic acid and ridecyl ester (25.88%) were the major phytocompounds. Conclusion Phytocompounds of A. annua can be used as bioenhancer of antibacterial and antifungal agents to control drug resistance.

Understanding the biosynthetic and regulatory mechanisms of heat-stable antifungal factor (HSAF) could improve the yield in Lysobacter enzymogenes. Here, we report that RpfB1 and RpfB2 encode acyl coenzyme A (CoA) ligases. Our research shows that RpfB1 and RpfB2 affect free fatty acid metabolism via fatty acyl-CoA ligase (FCL) activity to reduce the substrate for HSAF synthesis and, thereby, block HSAF production in L. enzymogenes. Furthermore, these findings reveal new roles for the fatty acyl-CoA ligases RpfB1 and RpfB2 in antibiotic biosynthesis in L. enzymogenes. Importantly, the novelty of this work is the finding that RpfB2 lies outside the Rpf gene cluster and plays a key role in HSAF production, which has not been reported in other diffusible signaling factor (DSF)/Rpf-producing bacteria., In Lysobacter enzymogenes OH11, RpfB1 and RpfB2 were predicted to encode acyl coenzyme A (CoA) ligases. RpfB1 is located in the Rpf gene cluster. Interestingly, we found an RpfB1 homolog (RpfB2) outside this canonical gene cluster, and nothing is known about its functionality or mechanism. Here, we report that rpfB1 and rpfB2 can functionally replace EcFadD in the Escherichia coli fadD mutant JW1794. RpfB activates long-chain fatty acids (n-C16:0 and n-C18:0) for the corresponding fatty acyl-CoA ligase (FCL) activity in vitro, and Glu-361 plays critical roles in the catalytic mechanism of RpfB1 and RpfB2. Deletion of rpfB1 and rpfB2 resulted in significantly increased heat-stable antifungal factor (HSAF) production, and overexpression of rpfB1 or rpfB2 completely suppressed HSAF production. Deletion of rpfB1 and rpfB2 resulted in increased L. enzymogenes diffusible signaling factor 3 (LeDSF3) synthesis in L. enzymogenes. Overall, our results showed that changes in intracellular free fatty acid levels significantly altered HSAF production. Our report shows that intracellular free fatty acids are required for HSAF production and that RpfB affects HSAF production via FCL activity. The global transcriptional regulator Clp directly regulated the expression of rpfB1 and rpfB2. In conclusion, these findings reveal new roles of RpfB in antibiotic biosynthesis in L. enzymogenes. IMPORTANCE Understanding the biosynthetic and regulatory mechanisms of heat-stable antifungal factor (HSAF) could improve the yield in Lysobacter enzymogenes. Here, we report that RpfB1 and RpfB2 encode acyl coenzyme A (CoA) ligases. Our research shows that RpfB1 and RpfB2 affect free fatty acid metabolism via fatty acyl-CoA ligase (FCL) activity to reduce the substrate for HSAF synthesis and, thereby, block HSAF production in L. enzymogenes. Furthermore, these findings reveal new roles for the fatty acyl-CoA ligases RpfB1 and RpfB2 in antibiotic biosynthesis in L. enzymogenes. Importantly, the novelty of this work is the finding that RpfB2 lies outside the Rpf gene cluster and plays a key role in HSAF production, which has not been reported in other diffusible signaling factor (DSF)/Rpf-producing bacteria.

The protein–polysaccharide fraction (AAF) isolated from the coelomic fluid of the earthworm Dendrobaena veneta destroys C. albicans cells by changing their morphology, disrupting cell division, and leading to cell death. Morphological changes in C. albicans cells induced by treatment with AAF were documented using DIC, SEM, and AFM. Congo Red staining showed that the fungal wall structure was changed after incubation with AAF. The effect on C. albicans cell walls was shown by AFM analysis of the surface roughness of fungal cell walls and changes in the wall thickness were visualized using Cryo-SEM. The FTIR analysis of C. albicans cells incubated with AAF indicated attachment of protein or peptide compounds to the fungal walls. The intact LC–ESI–MS analysis allowed accurate determination of the masses of molecules present in AAF. As shown by the chromatographic study, the fraction does not cross biological membranes. The Cryo-TEM analysis of AAF demonstrated the ability of smaller subunits to combine into larger agglomerates. AAF is thermally stable, which was confirmed by Raman spectroscopy. AAF can be considered as a potential antifungal antibiotic with activity against clinical C. albicans strains.

YajQ, a binding protein of the universal bacterial second messenger cyclic di-GMP (c-di-GMP), affects virulence in several bacterial pathogens, including Xanthomonas campestris. In this bacterium, YajQ interacts with the transcription factor LysR. Upon c-di-GMP binding, the whole c-di-GMP-YajQ-LysR complex is found to dissociate from DNA, resulting in virulence gene regulation. Here, we identify a YajQ-LysR-like system in the bacterial biocontrol agent Lysobacter enzymogenes OH11 that secretes an antifungal antibiotic, heat-stable antifungal factor (HSAF) against crop fungal pathogens. We show that the YajQ homologue, CdgL (c-di-GMP receptor interacting with LysR) affects expression of the HSAF biosynthesis operon by interacting with the transcription activator LysR. The CdgL-LysR interaction enhances the apparent affinity of LysR to the promoter region upstream of the HSAF biosynthesis operon, which increases operon expression. Unlike the homologues CdgL (YajQ)-LysR system in X. campestris, we show that c-di-GMP binding to CdgL seems to weaken CdgL-LysR interactions and promote the release of CdgL from the LysR-DNA complex, which leads to decreased expression. Together, this study takes the YajQ-LysR-like system from bacterial pathogens to a crop-protecting bacterium that is able to regulate antifungal HSAF biosynthesis via disassembly of the c-di-GMP receptor-transcription activator complex. Published version

Enzymes controlling intracellular second messengers in bacteria, such as c-di-GMP, often affect some but not other targets. How such specificity is achieved is understood only partially. Here, we present a novel mechanism that enables specific c-di-GMP-dependent inhibition of the antifungal antibiotic production. Expression of the biosynthesis operon for Heat-Stable Antifungal Factor, HSAF, in Lysobacter enzymogenes occurs when the transcription activator Clp binds to two upstream sites. At high c-di-GMP levels, Clp binding to the lower-affinity site is compromised, which is sufficient to decrease gene expression. We identified a weak c-di-GMP phosphodiesterase, LchP, that plays a disproportionately high role in HSAF synthesis due to its ability to bind Clp. Further, Clp binding stimulates phosphodiesterase activity of LchP. An observation of a signaling complex formed by a c-di-GMP phosphodiesterase and a c-di-GMP-binding transcription factor lends support to the emerging paradigm that such signaling complexes are common in bacteria, and that bacteria and eukaryotes employ similar solutions to the specificity problem in second messenger-based signaling systems.

Background The antifungal antibiotic UK-2A strongly inhibits mitochondrial electron transport at the Qi site of the cytochrome bc1 complex. Previous reports have described semi-synthetic modifications of UK-2A to explore the structure-activity relationship (SAR), but efforts to replace the picolinic acid moiety have been limited. Results Nineteen UK-2A analogs were prepared and evaluated for Qi site (cytochrome c reductase) inhibition and antifungal activity. While the majority are weaker Qi site inhibitors than UK-2A (IC50 , 3.8 nM), compounds 2, 5, 13 and 16 are slightly more active (IC50 , 3.3, 2.02, 2.89 and 1.55 nM, respectively). Compared to UK-2A, compounds 13 and 16 also inhibit growth of Zymoseptoria tritici and Leptosphaeria nodorum more strongly, while 2 and 13 provide stronger control of Z. tritici and Puccinia triticina in glasshouse tests. The relative activities of compounds 1-19 are rationalized based on a homology model constructed for the Z. tritici Qi binding site. Physical properties of compounds 1-19 influence translation of intrinsic activity to antifungal growth inhibition and in planta disease control. Conclusions The 3-hydroxy-4-methoxy picolinic acid moiety of UK-2A can be replaced by a variety of o-hydroxy-substituted arylcarboxylic acids that retain strong activity against Z. tritici and other agriculturally relevant fungi. © 2018 Society of Chemical Industry.