75 research outputs found
ΠΠΈΠ½Π³Π²ΠΈΡΡΠΈΡΠ΅ΡΠΊΠ°Ρ ΠΌΠΎΠ΄Π΅Π»Ρ Π²ΡΠ΅ΠΌΠ΅Π½ΠΈ Π² ΠΏΡΠ΅Π΄ΡΡΠ°Π²Π»Π΅Π½ΠΈΠΈ Π½ΠΎΡΠΈΡΠ΅Π»Π΅ΠΉ Π½Π΅Π±Π»ΠΈΠ·ΠΊΠΎΡΠΎΠ΄ΡΡΠ²Π΅Π½Π½ΡΡ ΡΠ·ΡΠΊΠΎΠ²
Π ΡΡΠ°ΡΡΠ΅ ΡΠ°ΡΡΠΌΠ°ΡΡΠΈΠ²Π°Π΅ΡΡΡ Π²ΠΎΠ·ΠΌΠΎΠΆΠ½ΠΎΡΡΡ ΡΡΡΠ΅ΡΡΠ²ΠΎΠ²Π°Π½ΠΈΡ Π΅Π΄ΠΈΠ½ΠΎΠΉ ΡΠ΅ΠΌΠΏΠΎΡΠ°Π»ΡΠ½ΠΎΠΉ ΠΌΠΎΠ΄Π΅Π»ΠΈ, ΡΠ²ΠΎΠΉΡΡΠ²Π΅Π½Π½ΠΎΠΉ Π½Π΅Π±Π»ΠΈΠ·ΠΊΠΎΡΠΎΠ΄ΡΡΠ²Π΅Π½Π½ΡΠΌ Π΅Π²ΡΠΎΠΏΠ΅ΠΉΡΠΊΠΈΠΌ ΡΠ·ΡΠΊΠ°ΠΌ. ΠΡΠ΅Π΄ΡΡΠ°Π²Π»Π΅Π½ΠΈΡ ΠΎ ΠΏΡΠΎΡΡΡΠ°Π½ΡΡΠ²Π΅ ΠΈ Π²ΡΠ΅ΠΌΠ΅Π½ΠΈ ΡΠ»Π΅Π΄ΡΠ΅Ρ ΡΡΠΈΡΠ°ΡΡ ΡΠΈΠ½ΠΊΡΠ΅ΡΠΈΡΠ½ΡΠΌΠΈ.Π£ ΡΡΠ°ΡΡΡ ΡΠΎΠ·Π³Π»ΡΠ΄Π°ΡΡΡΡΡ ΠΌΠΎΠΆΠ»ΠΈΠ²ΡΡΡΡ ΡΡΠ½ΡΠ²Π°Π½Π½Ρ Ρ Π½Π΅Π±Π»ΠΈΠ·ΡΠΊΠΎΡΠΏΠΎΡΡΠ΄Π½Π΅Π½ΠΈΡ
ΡΠ²ΡΠΎΠΏΠ΅ΠΉΡΡΠΊΠΈΡ
ΠΌΠΎΠ²Π°Ρ
ΡΠ΄ΠΈΠ½ΠΎΡ ΡΠ΅ΠΌΠΏΠΎΡΠ°Π»ΡΠ½ΠΎΡ ΠΌΠΎΠ΄Π΅Π»Ρ. Π£ΡΠ²Π»Π΅Π½Π½Ρ ΠΏΡΠΎ ΡΠ°Ρ Ρ ΠΏΡΠΎΡΡΡΡ ΡΠ»ΡΠ΄ Π²Π²Π°ΠΆΠ°ΡΠΈ ΡΠΈΠ½ΠΊΡΠ΅ΡΠΈΡΠ½ΠΈΠΌΠΈ.The article deals with the problem of the universal temporal model that exists in European languages. The main idea is that time and distance are visualized as syncretic notions
Fungal Automata
We study a cellular automaton (CA) model of information dynamics on a single
hypha of a fungal mycelium. Such a filament is divided in compartments (here
also called cells) by septa. These septa are invaginations of the cell wall and
their pores allow for flow of cytoplasm between compartments and hyphae. The
septal pores of the fungal phylum of the Ascomycota can be closed by organelles
called Woronin bodies. Septal closure is increased when the septa become older
and when exposed to stress conditions. Thus, Woronin bodies act as
informational flow valves. The one dimensional fungal automata is a binary
state ternary neighbourhood CA, where every compartment follows one of the
elementary cellular automata (ECA) rules if its pores are open and either
remains in state `0' (first species of fungal automata) or its previous state
(second species of fungal automata) if its pores are closed. The Woronin bodies
closing the pores are also governed by ECA rules. We analyse a structure of the
composition space of cell-state transition and pore-state transitions rules,
complexity of fungal automata with just few Woronin bodies, and exemplify
several important local events in the automaton dynamics
Computational universality of fungal sandpile automata
Hyphae within the mycelia of the ascomycetous fungi are compartmentalised by
septa. Each septum has a pore that allows for inter-compartmental and
inter-hyphal streaming of cytosol and even organelles. The compartments,
however, have special organelles, Woronin bodies, that can plug the pores. When
the pores are blocked, no flow of cytoplasm takes place. Inspired by the
controllable compartmentalisation within the mycelium of the ascomycetous fungi
we designed two-dimensional fungal automata. A fungal automaton is a cellular
automaton where communication between neighbouring cells can be blocked on
demand. We demonstrate computational universality of the fungal automata by
implementing sandpile cellular automata circuits there. We reduce the Monotone
Circuit Value Problem to the Fungal Automaton Prediction Problem. We construct
families of wires, cross-overs and gates to prove that the fungal automata are
P-complete
Attachment of Streptomyces coelicolor is mediated by amyloidal fimbriae that are anchored to the cell surface via cellulose
P>The chaplin proteins ChpA-H enable the filamentous bacterium Streptomyces coelicolor to form reproductive aerial structures by assembling into surface-active amyloid-like fibrils. We here demonstrate that chaplins also mediate attachment of S. coelicolor to surfaces. Attachment coincides with the formation of fimbriae, which are connected to the cell surface via spike-shaped protrusions. Mass spectrometry, electron microscopy and Congo red treatment showed that these fimbriae are composed of bundled amyloid fibrils of chaplins. Attachment and fimbriae formation were abolished in a strain in which the chaplin genes chpA-H were inactivated. Instead, very thin fibrils emerged from the spike-shaped protrusions in this mutant. These fibrils were susceptible to cellulase treatment. This enzymatic treatment also released wild-type fimbriae from the cell surface, thereby abolishing attachment. The reduced attachment of a strain in which the gene of a predicted cellulose synthase was inactivated also indicates a role of cellulose in surface attachment. We propose that the mechanism of attachment via cellulose-anchored amyloidal fimbriae is widespread in bacteria and may function in initiation of infection and in formation of biofilms
A broader role for AmyR in Aspergillus niger: regulation of the utilisation of d-glucose or d-galactose containing oligo- and polysaccharides
AmyR is commonly considered a regulator of starch degradation whose activity is induced by the presence of maltose, the disaccharide building block of starch. In this study, we demonstrate that the role of AmyR extends beyond starch degradation. Enzyme activity assays, genes expression analysis and growth profiling on d-glucose- and d-galactose-containing oligo- and polysaccharides showed that AmyR regulates the expression of some of the Aspergillus niger genes encoding alpha- and beta-glucosidases, alpha- and beta- galactosidases, as well as genes encoding alpha-amlyases and glucoamylases. In addition, we provide evidence that d-glucose or a metabolic product thereof may be the inducer of the AmyR system in A. niger and not maltose, as is commonly assumed
LaeA-dependent production of small molecules of Aspergillus niger that compete with specific antibodies that bind to human immune receptors
Microorganisms secrete a variety of compounds into their environment such as proteins, carbohydrates, and secondary metabolites. These molecules play diverse roles in the interaction of microbes with their abiotic and biotic environment. Little is known about secreted fungal molecules mediating immune evasion. Here we screened culture media of three Aspergilli to assess whether these fungi secrete molecules that can compete with specific antibodies that bind to human immune receptors. Culture media of Aspergillus fumigatus Af293, Aspergillus tubingensis CBS 133792 and the non-acidifying mutant strain Aspergillus niger D15#26 contained components that showed competition for binding to a total of 13 receptors, of which PSGL-1, CXCR1, and CXCR2, were shared between the three species. Filtration experiments showed that most, if not all, interacting components were [≤] 3 kDa. Production of the components that competed with antibodies to bind to CD88 and CXCR2 was shown to be regulated by LaeA. The component(s) that competed for binding to CXCR1 was not only produced in the non-acidifying strain Aspergillus niger D15#26 but also in the non-acidifying oahA deletion strain of Aspergillus niger. Together, these data show that Aspergillus species might produce small molecules that interact with human immune receptors
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