Quality and methods of adulteration of meat and fish products on the Polish market in 2010-2020.

Background: Globalisation is the direct or indirect source and cause of many economic, social, political and cultural processes and phenomena. These processes also affect agribusiness and food production. One of the important developments in recent decades is the ever-increasing scale of food adulteration.

[Effector proteins of phytopathogens recognized by intracellular immune receptors NB-LRR/NLR that activate second line of defence of the plant immune system].

The effector proteins employ common as well as pathogen-specific strategies to disturb plant immunity and to promote pathogen survival and favor their multiplication. However, in some cases, pathogen effectors are recognized by plant intracellular immune receptors NB-LRR/NLR that identify effector proteins, either directly by physical interaction or indirectly through monitoring of host proteins modification. NB-LRR immune receptors are characterized by the central nucleotide binding domain NB-ARC, C-terminal Leucine-Rich Repeats (LRRs) domain, and N-terminal TIR, CC or CCR domain.

[Suppression of PAMP-triggered immunity (PTI) by effector proteins synthesized by phytopathogens and delivered into cells of infected plant].

Plant immunity is constituted by multilayered system involving two intertwined lines of defence: a first level of immunity termed PAMP-triggered immunity (PTI) or basal resistance, and a second layer of plant defence, called effector-triggered immunity (ETI). The second line of defence depends on the ability of the plant to recognize phytopathogen-synthesized effector proteins delivered into host plant cells. The effector proteins employ common as well as pathogen-specific strategies to disturb plant immunity and to promote pathogen survival and favor their multiplication.

[Membrane receptors recognizing MAMP/PAMP and DAMP molecules that activate first line of defence in plant immune system].

Plants have evolved a multilevel immune system to protect them against infection by a diverse range of pathogens. The first line of plant defense consists of the integral plasma membrane receptors, known as pattern-recognition receptors (PRRs), which recognize MAMP/PAMP or DAMP molecules. PRRs activate downstream signaling cascades that culminate in generation of the innate immune response, called PAMP-triggered immunity (PTI).

[Plant signaling peptides. Cysteine-rich peptides].

Recent bioinformatic and genetic analyses of several model plant genomes have revealed the existence of a highly abundant group of signaling peptides that are defined as cysteine-rich peptides (CRPs). CRPs are usually in size between 50 and 90 amino acid residues, they are positively charged, and they contain 4-16 cysteine residues that are important for the correct conformational folding. Despite the structural differences among CRP classes, members from each class have striking similarities in their molecular properties and function.

Authenticity of food products in the Polish market checked during 2005-2012.

Background: Food fraud/adulteration has ever increasingly become a dominant food issue of the modern world in both developed and developing countries. It is presumed that globalisation is mainly one of the underlying reasons.

Objectives: To assess and analyse the occurrence of food fraud on the Polish market during 2005-2012.

[Plant signaling peptides. Small post-translationally modified peptides].

Recent genetic, bioinformatic and biochemical analyses have revealed that many secretory peptides are important components in intercellular signaling that coordinate and specify cellular functions in plants. The signaling peptides discovered in plants thus far can be considered to fall into two broad groups. Peptides from the first group are undergo post-translational modification, such as proline hydroxylation, hydroxyproline arabinosylation or tyrosine sulfation.

[Small, monomeric G proteins in plants].

The superfamily of small, monomeric GTP-binding proteins, in Arabidopsis thaliana comprising 93 members, is classified into four families: Arf/Sar, Rab, Rop/Rac, and Ran families. All monomeric G proteins function as molecular switches that are activated by GTP and inactivated by the hydrolysis of GTP to GDP. GTP/GDP cycling is controlled by three classes of regulatory protein: guanine-nucleotide-exchange factors (GEFs), GTPase-activating proteins (GAPs), and guanine-nucleotide-dissociation inhibitors (GDIs).

Nucleoside diphosphate kinase isoforms regulated by phytochrome A isolated from oat coleoptiles.

Nucleoside diphosphate kinase (NDPK) (EC 2.7.4.

[G-protein-coupled receptors, heterotrimeric G-proteins and protein effectors in plants].

The superfamily of G-protein-coupled receptors (GPCRs) is one of the largest and most diverse family of proteins in mammals. Plants, in contrast to animals, have a greatly simplified repertoire of GPCRs. To date, only AtGCR1 and AtRGS1 have been shown to physically interacts with a plant G-protein.

[Plant receptor kinases].

Recent plant genome analyses have revealed a large number of genes encoding receptor-like kinases (RLKs) in plants. Theyare transmembrane proteins structurally related to the animal tyrosine and serin/threonine families with differences in their extracellular domains. There are more than 20 classes of plant RLKs, distinguished according to their extracellular domains, which can potentially bind an array of molecules.

[Plant ubiquitylation and proteolytic systems, the key elements in hormonal signaling pathways].

The general function of the ubiquitylation systems is to conjugate ubiquitin to lysine residues within substrate proteins, thus targeting them for degradation by the proteasome. In Arabidopsis thaliana more than 1300 genes (approximately 5% of the proteome) encode components of the ubiquitin/26S proteasome pathway. Approximately 90% of these genes encode subunits of the E3 ubiquitin ligases, which confer substrate specificity to the ubiquitin/26S proteasome pathway.

A specific enzyme hydrolyzing 6-O(4-O)-indole-3-ylacetyl-beta-D-glucose in immature kernels of Zea mays.

The purification of 6-O(4-O)-indole-3-ylacetyl-beta-D-glucose (IAGlc) hydrolase from immature kernels of maize (Zea mays) was undertaken to separate this enzyme from 1-O-IAGlc hydrolase and beta-glucosidase. Partially purified 6-O(4-O)-IAGlc hydrolase was found to be the specific enzyme catalyzing hydrolysis of stable esters of IAA and glucose. Among a range of ester conjugates tested as substrates, only 6-O(4-O)-IAA-glucose and IBA-glucose isomers were effectively hydrolyzed.

The auxin conjugate 1-O-indole-3-acetyl-beta-D-glucose is synthesized in immature legume seeds by IAGlc synthase and may be used for modification of some high molecular weight compounds.

Immature seeds of some dicotyledonous plants contain IAGlc synthase catalysing the synthesis of 1-O-IAGlc. This enzyme activity is comparable with 1-O-IAGlc synthase activity investigated earlier in liquid endosperm of Zea mays. Polyclonal antibodies against maize 1-O-IAGlc synthase cross-react with partially purified 1-O-IAGlc synthase from immature pea and rape seeds.