40 research outputs found
Are cysteine and its derivatives applicable for the prevention of fungal diseases?
Many filamentous fungi are destructive pathogens of plants and are thus responsible for
enormous crop losses worldwide. Therefore, there is a substantial demand for safely
applicable, new compounds with extensive antifungal activity. Cysteine and its derivatives
are interesting from this respect, as they have effective inhibitory potential against
microorganisms and do not harmful effect on animal and plant cells.
Cysteine is a non-essential amino acid, which is an important structural and functional
component of many proteins and enzymes. Previous studies demonstrated that cysteine and
N-acetyl-cysteine have also been shown to exert antifungal activity.
A number of members of the class Zygomycetes are important as postharvest pathogens of
agricultural products; Rhizopus, Mucor and Gilbertella species are among the most
frequently isolated causative agents of fungal rots.
In this study we investigated the in vitro antifungal activity of cysteine (D- and L-cysteine)
and its 4 derivatives (L-cysteine-methyl-ester, N-acetyl-cysteine, N-isobutyryl-D-cysteine
and N-isobutyryl-L-cysteine) against 20 zygomyceteous fungal isolates representing 16
genera (Actinomucor, Backusella, Gilbertella, Lichtheimia, Micromucor, Mortierella,
Mucor, Mycotypha, Phycomyces, Rhizomucor, Rhizopus, Saksenaea, Syncephalastrum,
Thamnostylum, Umbellopsis and Zygorynchus).
The inhibitory potential of different concentrations (ranging from 0.625 to 10 mM) of the
cysteine and its derivatives were investigated on the germination of sporangiospores and
on hyphal extension by broth microdilution method and agar plate test. Cysteine and its
derivatives showed a strong inhibitory effect against the most studied strains. Treatment
with 10 mM of compounds resulted total growth inhibition in case of some isolates. Severe
changes in colony morphology and hyphal growth were observed in presence of 10 mM Lcysteine,
N-acetyl-cysteine and N-isobutyryl-L-cysteine when a strain was sensitive to
them. Ten mM N-acetyl-cysteine induced dramatic modifications in the structural
organization of the hyphae in case of Rhizopus stolonifer.
The above mentioned features of the investigated compounds could make them favourable
antifungal agents against Zygomycetes in agricultural respect in the future, but it is needed
further studies to prove their practical efficiency, for example in plant model experiments
A hĆkezelĂ©s alkalmazĂĄsi lehetĆsĂ©gei a kriminalisztikai ĂŒvegvizsgĂĄlatokban
Aim: In this paper, our primary aim is to present the results of our experiments, carried out at the Hungarian Institute for Forensic Sciences, as well as the possible applications of annealing in the forensic investigation of glasses.Methodology: The question that typically arises and requires forensic examinations in connection with crimes involving the breaking of glasses (e. g. burglary, vandalism) is whether the glass fragments recovered from the suspectâs garment can originate from any of the broken samples found on the scene of the crime. A common method for forensic investigation of glass microfragments is the refractive index measurement. In cases when the refractive index of the recovered fragments and the reference is the same, it is probable that they originate from the same source. These investigations can be supplemented by the heat treatment of the glass samples under controlled conditions followed by the measurement of the refractive index. In this work we present this method via examples, comparing the results with previous literature data.Findings: As a result of annealing, a structural rearrangement takes place inside the glass fragments and the refractive index changes. The extent of this change is characteristic of the glass types due to the different internal stress present in the different types. Besides establishing a more precise relationship of origin, this method also makes it possible to determine glasses by type. Annealing has also been successfully applied in cases where direct comparison of the recovered fragments with the reference sample would have given false results due to the significant heat effect (e. g. fire) on the control sample after the crime.Value: We have successfully applied annealing to determine the type of glasses, to examine the possibilities of origin, and to analyze glasses exposed to heat, thus helping to answer forensic questions in criminal cases.CĂ©l: Az alĂĄbbiakban cĂ©lunk bemutatni a Nemzeti SzakĂ©rtĆi Ă©s KutatĂł Központban vĂ©gzett, ĂŒvegek hĆkezelĂ©sĂ©vel kapcsolatos kĂsĂ©rletek eredmĂ©nyeit, valamint a hĆkezelĂ©s alkalmazĂĄsi lehetĆsĂ©geit a kriminalisztikai vizsgĂĄlatokban.MĂłdszertan: Az ĂŒvegek törĂ©sĂ©vel is egyĂŒtt jĂĄrĂł bƱncselekmĂ©nyekkel (pĂ©ldĂĄul gĂ©pjĂĄrmƱfeltörĂ©s, betörĂ©ses lopĂĄs, rongĂĄlĂĄs) kapcsolatosan jellemzĆen felmerĂŒlĆ, szakĂ©rtĆi vizsgĂĄlatot igĂ©nylĆ kĂ©rdĂ©s, hogy a lefoglalt ruhĂĄzati tĂĄrgyon talĂĄlt ĂŒvegszemcse szĂĄrmazhat-e a bƱncselekmĂ©ny helyszĂnĂ©n eltört ĂŒvegtĂĄrgyak valamelyikĂ©bĆl. MikromĂ©retƱ ĂŒvegszemcsĂ©k kriminalisztikai vizsgĂĄlatĂĄnak elterjedt mĂłdszere az optikai törĂ©smutatĂł mĂ©rĂ©s. Az ĂŒvegmaradvĂĄny-szemcse Ă©s a referenciaminta törĂ©smutatĂłjĂĄnak azonossĂĄga esetĂ©n valĂłszĂnƱsĂthetĆ a szĂĄrmazĂĄsi kapcsolat. Az ilyen jellegƱ vizsgĂĄlatok kiegĂ©szĂtĂ©sekĂ©nt szolgĂĄl az ĂŒvegszemcsĂ©k kontrollĂĄlt körĂŒlmĂ©nyek között törtĂ©nĆ hĆkezelĂ©se Ă©s az azt követĆ optikai törĂ©smutatĂł mĂ©rĂ©s. Jelen munkĂĄnk sorĂĄn ezt a vizsgĂĄlati lehetĆsĂ©get mutatjuk be pĂ©ldĂĄkon keresztĂŒl, az eredmĂ©nyeket összevetve korĂĄbbi irodalmi adatokkal.MegĂĄllapĂtĂĄsok: HĆkezelĂ©s hatĂĄsĂĄra az ĂŒvegszemcsĂ©n belĂŒl szerkezeti ĂĄtrendezĆdĂ©s törtĂ©nik, melynek hatĂĄsĂĄra a szemcse optikai törĂ©smutatĂłja megvĂĄltozik. Ennek mĂ©rtĂ©ke a kĂŒlönbözĆ tĂpusĂș ĂŒvegekben jelen lĂ©vĆ, eltĂ©rĆ belsĆ feszĂŒltsĂ©g miatt ĂŒvegtĂpusonkĂ©nt kĂŒlönbözĆ Ă©s jellegzetes. Ez lehetĆsĂ©get nyĂșjt a pontosabb szĂĄrmazĂĄsi viszony megĂĄllapĂtĂĄsa mellett az ĂŒveg tĂpusĂĄnak meghatĂĄrozĂĄsĂĄra is. A hĆkezelĂ©st olyan esetekben is sikerrel alkalmaztuk, ahol a bƱncselekmĂ©nyt követĆen a referenciamintĂĄt Ă©rt jelentĆs hĆterhelĂ©s (pĂ©ldĂĄul tƱz) miatt az ĂŒvegmaradvĂĄny-szemcsĂ©kkel optikai törĂ©smutatĂł alapjĂĄn törtĂ©nĆ közvetlen összehasonlĂtĂĄs tĂ©ves eredmĂ©nyt adna.ĂrtĂ©k: Sikeresen alkalmaztuk a hĆkezelĂ©st ĂŒvegtĂpus megĂĄllapĂtĂĄsĂĄra, szĂĄrmazĂĄsi viszonyok vizsgĂĄlatĂĄra, valamint hĆterhelĂ©snek kitett ĂŒvegek analĂzisĂ©reis, ezzel segĂtve a bĂŒntetĆĂŒgyekben felmerĂŒlĆ szakkĂ©rdĂ©sek megvĂĄlaszolĂĄsĂĄt
A hĆkezelĂ©s alkalmazĂĄsi lehetĆsĂ©gei a kriminalisztikai ĂŒvegvizsgĂĄlatokban
CĂ©l: Az alĂĄbbiakban cĂ©lunk bemutatni a Nemzeti SzakĂ©rtĆi Ă©s KutatĂł Központban vĂ©gzett, ĂŒvegek hĆkezelĂ©sĂ©vel kapcsolatos kĂsĂ©rletek eredmĂ©nyeit, valamint a hĆkezelĂ©s alkalmazĂĄsi lehetĆsĂ©geit a kriminalisztikai vizsgĂĄlatokban. MĂłdszertan: Az ĂŒvegek törĂ©sĂ©vel is egyĂŒtt jĂĄrĂł bƱncselekmĂ©nyekkel (pĂ©ldĂĄul gĂ©pjĂĄrmƱfeltörĂ©s, betörĂ©ses lopĂĄs, rongĂĄlĂĄs) kapcsolatosan jellemzĆen felmerĂŒlĆ, szakĂ©rtĆi vizsgĂĄlatot igĂ©nylĆ kĂ©rdĂ©s, hogy a lefoglalt ruhĂĄzati tĂĄrgyon talĂĄlt ĂŒvegszemcse szĂĄrmazhat-e a bƱncselekmĂ©ny helyszĂnĂ©n eltört ĂŒvegtĂĄrgyak valamelyikĂ©bĆl. MikromĂ©retƱ ĂŒvegszemcsĂ©k kriminalisztikai vizsgĂĄlatĂĄnak elterjedt mĂłdszere az optikai törĂ©smutatĂł mĂ©rĂ©s. Az ĂŒvegmaradvĂĄny-szemcse Ă©s a referenciaminta törĂ©smutatĂłjĂĄnak azonossĂĄga esetĂ©n valĂłszĂnƱsĂthetĆ a szĂĄrmazĂĄsi kapcsolat. Az ilyen jellegƱ vizsgĂĄlatok kiegĂ©szĂtĂ©sekĂ©nt szolgĂĄl az ĂŒvegszemcsĂ©k kontrollĂĄlt körĂŒlmĂ©nyek között törtĂ©nĆ hĆkezelĂ©se Ă©s az azt követĆ optikai törĂ©smutatĂł mĂ©rĂ©s. Jelen munkĂĄnk sorĂĄn ezt a vizsgĂĄlati lehetĆsĂ©get mutatjuk be pĂ©ldĂĄkon keresztĂŒl, az eredmĂ©nyeket összevetve korĂĄbbi irodalmi adatokkal. MegĂĄllapĂtĂĄsok: HĆkezelĂ©s hatĂĄsĂĄra az ĂŒvegszemcsĂ©n belĂŒl szerkezeti ĂĄtrendezĆdĂ©s törtĂ©nik, melynek hatĂĄsĂĄra a szemcse optikai törĂ©smutatĂłja megvĂĄltozik. Ennek mĂ©rtĂ©ke a kĂŒlönbözĆ tĂpusĂș ĂŒvegekben jelen lĂ©vĆ, eltĂ©rĆ belsĆ feszĂŒltsĂ©g miatt ĂŒvegtĂpusonkĂ©nt kĂŒlönbözĆ Ă©s jellegzetes. Ez lehetĆsĂ©get nyĂșjt a pontosabb szĂĄrmazĂĄsi viszony megĂĄllapĂtĂĄsa mellett az ĂŒveg tĂpusĂĄnak meghatĂĄrozĂĄsĂĄra is. A hĆkezelĂ©st olyan esetekben is sikerrel alkalmaztuk, ahol a bƱncselekmĂ©nyt követĆen a referenciamintĂĄt Ă©rt jelentĆs hĆterhelĂ©s (pĂ©ldĂĄul tƱz) miatt az ĂŒvegmaradvĂĄny-szemcsĂ©kkel optikai törĂ©smutatĂł alapjĂĄn törtĂ©nĆ közvetlen összehasonlĂtĂĄs tĂ©ves eredmĂ©nyt adna. ĂrtĂ©k: Sikeresen alkalmaztuk a hĆkezelĂ©st ĂŒvegtĂpus megĂĄllapĂtĂĄsĂĄra, szĂĄrmazĂĄsi viszonyok vizsgĂĄlatĂĄra, valamint hĆterhelĂ©snek kitett ĂŒvegek analĂzisĂ©reis, ezzel segĂtve a bĂŒntetĆĂŒgyekben felmerĂŒlĆ szakkĂ©rdĂ©sek megvĂĄlaszolĂĄsĂĄt
Are cysteine and its derivatives applicable for the prevention of fungal diseases?
Many filamentous fungi are destructive pathogens of plants and are thus responsible for enormous crop losses worldwide. Therefore, there is a substantial demand for safely applicable, new compounds with extensive antifungal activity. Cysteine and its derivatives are interesting from this respect, as they have effective inhibitory potential against microorganisms and do not harmful effect on animal and plant cells. Cysteine is a non-essential amino acid, which is an important structural and functional component of many proteins and enzymes. Previous studies demonstrated that cysteine and N-acetyl-cysteine have also been shown to exert antifungal activity. A number of members of the class Zygomycetes are important as postharvest pathogens of agricultural products; Rhizopus, Mucor and Gilbertella species are among the most frequently isolated causative agents of fungal rots. In this study we investigated the in vitro antifungal activity of cysteine (D- and L-cysteine) and its 4 derivatives (L-cysteine-methyl-ester, N-acetyl-cysteine, N-isobutyryl-D-cysteine and N-isobutyryl-L-cysteine) against 20 zygomyceteous fungal isolates representing 16 genera (Actinomucor, Backusella, Gilbertella, Lichtheimia, Micromucor, Mortierella, Mucor, Mycotypha, Phycomyces, Rhizomucor, Rhizopus, Saksenaea, Syncephalastrum, Thamnostylum, Umbellopsis and Zygorynchus). The inhibitory potential of different concentrations (ranging from 0.625 to 10 mM) of the cysteine and its derivatives were investigated on the germination of sporangiospores and on hyphal extension by broth microdilution method and agar plate test. Cysteine and its derivatives showed a strong inhibitory effect against the most studied strains. Treatment with 10 mM of compounds resulted total growth inhibition in case of some isolates. Severe changes in colony morphology and hyphal growth were observed in presence of 10 mM Lcysteine, N-acetyl-cysteine and N-isobutyryl-L-cysteine when a strain was sensitive to them. Ten mM N-acetyl-cysteine induced dramatic modifications in the structural organization of the hyphae in case of Rhizopus stolonifer. The above mentioned features of the investigated compounds could make them favourable antifungal agents against Zygomycetes in agricultural respect in the future, but it is needed further studies to prove their practical efficiency, for example in plant model experiments
Taxonomic and metabolic investigation of bipolaris species
The ascomycetous genus Bipolaris (Euascomycetes, Pleosporales, Pleosporaceae) contains melanin producing filamentous fungal species. Teleomorphic stages belong to the genus Cochliobolus together with the members of the other anamorphic genus, Curvularia; however, sexual reproduction has been rarely observed in nature. These fungi are frequently associated to graminaceous hosts and may infect corn, wheat, barley and rice causing devastating epidemics from time to time, primarily in tropical and subtropical regions. Climate change favours the spreading of these species in temperate regions, which underlines the importance of their study. The symptoms of Bipolaris infections begin with small necrotic lesions on leafs, which extends and cause notable yield losses. Bipolaris species produce a series of biological active secondary metabolites, which have or may have role in the pathogenesis. They produce various terpenoid compounds, such as sesquiterpenes, diterpenes and sesterterpenes. The sesterterpene-type ophiobolins constitute one of the most remarkable groups of these bioactive metabolites. Apart from their phytotoxic effects, several ophiobolin analogues have antimicrobial, antiviral, cytotoxic, anticancer, or nematocidal activity. Besides plant pathogenicity, the genus is also known about their difficult species identification and confused taxonomy. Traditional morphology based methods are unsuitable for the precise species identification because of the similar characteristics, molecular identification based on the frequently used nuclear ribosomal ITS region is also problematic. In the present study, new markers potentially suitable for molecular identification were tested. Our study demonstrated that the ITS region, the calm, tub and tef gene sequences, which are routinely used for identification, are unsuitable to discern Bipolaris species. Instead of them the use of the intergenic spacer region (IGS) of the nuclear ribosomal RNA gene cluster is suggested, in which species specific motifs were determined to distinguish the Bipolaris isolates. Furthermore, ability of Bipolaris and Cochliobolus isolates representing 23 different species to produce ophiobolin A, the best known phytotoxin of these fungi, was also investigated. Six of the tested isolates produced remarkable amounts of ophiobolin A (>1 mg/g [dry weight]). The secretion kinetics of the examined strains has been determined by HPLC technique during a 12 days long cultivation and found to be aggregated in four different groups according to the results. This study forms part of the project TĂMOP-4.2.2.A-11/1/KONV-2012-0035, supported by the European Union, co-financed by the European Social Fund. For Cs.V: this research was realized in the frames of TĂMOP 4.2.4. A/2-11-1-2012-0001 âNational Excellence Program â Elaborating and operating an inland student and researcher personal support systemâ. The project was subsidized by the European Union and co-financed by the European Social Fund
New Species of the Genus Curvularia: C. tamilnaduensis and C. coimbatorensis from Fungal Keratitis Cases in South India
Experimental investigations on the pollen grains of Malva sylvestris L. and Hibiscus syriacus L. I.
Comparative genomics reveals the origin of fungal hyphae and multicellularity
Hyphae represent a hallmark structure of multicellular fungi. The evolutionary origins of hyphae and of the underlying genes are, however, hardly known. By systematically analyzing 72 complete genomes, we here show that hyphae evolved early in fungal evolution probably via diverse genetic changes, including co-option and exaptation of ancient eukaryotic (e.g. phagocytosis-related) genes, the origin of new gene families, gene duplications and alterations of gene structure, among others. Contrary to most multicellular lineages, the origin of filamentous fungi did not correlate with expansions of kinases, receptors or adhesive proteins. Co-option was probably the dominant mechanism for recruiting genes for hypha morphogenesis, while gene duplication was apparently less prevalent, except in transcriptional regulators and cell wall - related genes. We identified 414 novel gene families that show correlated evolution with hyphae and that may have contributed to its evolution. Our results suggest that hyphae represent a unique multicellular organization that evolved by limited fungal-specific innovations and gene duplication but pervasive co-option and modification of ancient eukaryotic functions