Interaction of causative agents of sapronoses with the land plant Lithospermum erythrorhizon

Background. A significant role in the ecology of the sapronotic pathogens Yersinia pseudotuberculosis and Listeria monocytogenes and in the epidemiology of the infections they cause is played by land plants used for food. These microorganisms are often found on plant substrates, they multiply on various vegetable and root crops. In this regard, it is relevant to study the viability and biological activity of Y. pseudotuberculosis and L. monocytogenes in contact with various land plants, including those that are not eaten, but are used in medicine.Aim. Study of the interaction of sapronotic pathogens Y. pseudotuberculosis and L. monocytogenes with callus cultures of the land plant Lithospermum erythrorhizon Siebold et Zucc.Materials and methods. The studies included strains of Y. pseudotuberculosis 512 serotype 1b, pYV+, 82MD+ and L. monocytogenes NCTC (4b) 10527 from the Collection of Somov Institute of Epidemiology and Microbiology, and cell culture from the roots of red-root gromwell Lithospermum erythrorhizon line VC-39 (from the Collection of FSC of the East Asia Terrestrial Biodiversity FEB RAS).Before the study, Y. pseudotuberculosis and L . monocytogenes were cultured 18–20 hours on nutrient agar pH 7.1–7.2. A working dilution of microorganisms was prepared (106 micobial cells per 1 ml) and applied at a dose of 100 μl to the surface of plant calli. Material samples were taken in dynamics after 3 and 14 days and prepared for scanning electron microscopy.Results. Y. pseudotuberculosis and L. monocytogenes formed biofilms on the surface of plant cells within 3 days after the start of the experiment. It was noted that Y. pseudotuberculosis destroyed the components of the plant cell membrane.Conclusion. New data obtained during the study expand the understanding of environments and forms of habitation, as well as the potential for pathogenicity of sapronotic pathogens in the environment.

Thylakoid grana stacking revealed by multiplex genome editing of LHCII encoding genes

Land plant chloroplasts differ from algal ones for their thylakoid membranes being organized in grana: piles of vesicles paired by their stromal surface, forming domains including Photosystem (PS) II and its antenna while excluding PS I and ATPase to stroma membranes, connecting grana stacks. The molecular basis of grana stacking remain unclear. We obtained genotypes lacking the trimeric antenna complex (Lhcb1-2-3), the monomeric Lhcb4-5-6, or both. Full deletion caused loss of grana, while either monomers or trimers support 50% stacking. The expression of Lhcb5 alone restored stacking at 50%, while Lhcb2 alone produced huge grana which broke down upon light exposure. Cyclic electron transport was maintained in the lack of stacking, while excitation energy balance between photosystems and the repair efficiency of damaged Photosystem II were affected. We conclude that grana evolved for need of regulating energy balance between photosystems under terrestrial canopy involving rapid changes in photon spectral distribution.

Paleoenvironments and Hydrocarbon Potential of Upper Cretaceous Shales in Agbabu-1 Well, Dahomey Basin SW Nigeria

Upper Cretaceous shales partially exposed in the northern fringes of the Dahomey Basin are well developed in the subsurface in Southwestern part of the basin where Agbau-1 well is sited. These shales were evaluated in respect to their paleoenvironments and potentials for hydrocarbon using foraminiferal assemblages, biomarkers and Rock Eval pyrolysis studies. The dominance of benthonic foraminifera species suggests a shallow marine environment and high percentage of calcareous to arenaceous benthic www.eujournal.org 195foraminifera indicate high water salinity and hypersline environment. Dysoxic oxygen condition is also prevalent probably because most of the benthic foraminifera recovered are epifauna that live in a reduced oxygen condition. 1.90 wt%, 244 mgHC/gTOC and 429℃ average values of total organic carbon, hydrogen index and Tmax reveal that the Upper Cretaceous shales have relatively fair to good organic matter, predominantly Type II-III kerogen and currently immature. Though three is a trend of an increase in maturity down the hole. All the steranes have uniform distributions (C27>C28>C29), suggesting a relatively higher input from the marine red algae and a low level of land plant contribution to the source organic matter. Pristane/phytane ratios and C29/C27 steranes confirmed the organic matter type to be a Type II/III and anoxic source rock depositional condition as well as a reducing diagenetic system in the sediment water column. The Upper Cretaceous shales in Dahomey Basin can be targeted for exploration as an unconventional petroleum resource.

KARAKTERISTIK PENGELOLAAN HUTAN RAKYAT DALAM PERSPEKTIF SISTEM (Studi di Desa Semoyo Kabupaten Gunung Kidul)

. Community smallholder forests in various places in Indonesia have different characteristics that depend on many factors that cause the development of community smallholder forests. This study aims to determine the characteristics of community smallholder forest management, the components and the interrelationships between the components that constructed the community smallholder forest system. The study was conducted at Semoyo Village, Gunungkidul Regency. Data were collected by interviewing seventy-two respondents who were purposively chosen, then tabulated and analyzed in a descriptive qualitative manner. Diameter of tree measurements on the respondent's forest land are carried out by census. In the next stage, the construction of the community smallholder forest system is carried out in a causal loop diagram based on the management characteristics found. The results show that the community smallholder forest system is composed of the main components of cultivated land, plant resources, human resources, management activities, and the purpose of managing forests. The component of land resources and human resources determines the agroforestry planting patterns chosen. The activity components, which are planting, maintaining, and cutting, have a positive loop and form different stand structures in different agroforestry planting patterns

Identification of Partner Proteins of the Algae Klebsormidium nitens NO Synthases: Toward a Better Understanding of NO Signaling in Eukaryotic Photosynthetic Organisms

In animals, NO is synthesized from L-arginine by three isoforms of nitric oxide synthase (NOS) enzyme. NO production and effects have also been reported in plants but the identification of its sources, especially the enzymatic ones, remains one of the critical issues in the field. NOS-like activities have been reported, although there are no homologs of mammalian NOS in the land plant genomes sequenced so far. However, several NOS homologs have been found in algal genomes and transcriptomes. A first study has characterized a functional NOS in the chlorophyte Ostreococcus tauri and the presence of NOS homologs was later confirmed in a dozen algae. These results raise the questions of the significance of the presence of NOS and their molecular diversity in algae. We hypothesize that comparisons among protein structures of the two KnNOS, together with the identification of their interacting partner proteins, might allow a better understanding of the molecular diversification and functioning of NOS in different physiological contexts and, more generally, new insights into NO signaling in photosynthetic organisms. We recently identified two NOS homologs sequences in the genome of the streptophyte Klebsormidium nitens, a model alga in the study of plant adaptation to terrestrial life. The first sequence, named KnNOS1, contains canonical NOS signatures while the second, named KnNOS2, presents a large C-ter extension including a globin domain. In order to identify putative candidates for KnNOSs partner proteins, we draw the protein–protein interaction networks of the three human NOS using the BioGRID database and hypothesized on the biological role of K. nitens orthologs. Some of these conserved partners are known to be involved in mammalian NOSs regulation and functioning. In parallel, our methodological strategy for the identification of partner proteins of KnNOS1 and KnNOS2 by in vitro pull-down assay is presented.

Evolution of RGF/GLV/CLEL Peptide Hormones and Their Roles in Land Plant Growth and Regulation

Rooting is a key innovation during plant terrestrialization. RGFs/GLVs/CLELs are a family of secreted peptides, playing key roles in root stem cell niche maintenance and pattern formation. The origin of this peptide family is not well characterized. RGFs and their receptor genes, RGIs, were investigated comprehensively using phylogenetic and genetic analyses. We identified 203 RGF genes from 24 plant species, representing a variety of land plant lineages. We found that the RGF genes originate from land plants and expand via multiple duplication events. The lineage-specific RGF duplicates are retained due to their regulatory divergence, while a majority of RGFs experienced strong purifying selection in most land plants. Functional analysis indicated that RGFs and their receptor genes, RGIs, isolated from liverwort, tomato, and maize possess similar biological functions with their counterparts from Arabidopsis in root development. RGFs and RGIs are likely coevolved in land plants. Our studies shed light on the origin and functional conservation of this important peptide family in plant root development.

“Neptune Balls” Polysaccharides: Disentangling the Wiry Seagrass Detritus

Each year, high amounts of dead seagrass material are washed ashore at beaches world-wide. In the Mediterranean region, the seagrass Posidonia oceanica is responsible for huge agglomerates of ball-like seagrass litter. As these are often removed due to touristic reasons, a reuse method would be a step towards a more ecologically oriented society. In this study, the main polysaccharide components were analyzed, in order to propose possible usage options. To do this, different aqueous fractions were extracted, analyzed by classical carbohydrate analysis methods (GC-FID/MS, colorimetric assay and elemental analysis), and purified by ion-exchange chromatography, as well as selective precipitation with a detecting agent for highly glycosylated glycoproteins. The obtained purified fractions were analyzed in detail and a linkage-type analysis of the most promising extract was conducted via permethylation. Only low amounts of glycoproteins, as well as medium amounts of the characteristic apiogalacturonan were likely to be present, while xylan seemed to be the most abundant polysaccharide in most fractions. A partial structural proposal showed general accordance with land plant xylans, presenting reuse options in the field of biofuel and bioplastic generation.

Cytokinin Perception in Ancient Plants beyond Angiospermae

Cytokinins (CKs) control many plant developmental processes and responses to environmental cues. Although the CK signaling is well understood, we are only beginning to decipher its evolution. Here, we investigated the CK perception apparatus in early-divergent plant species such as bryophyte Physcomitrium patens, lycophyte Selaginella moellendorffii, and gymnosperm Picea abies. Of the eight CHASE-domain containing histidine kinases (CHKs) examined, two CHKs, PpCHK3 and PpCHK4, did not bind CKs. All other CHK receptors showed high-affinity CK binding (KD of nM range), with a strong preference for isopentenyladenine over other CK nucleobases in the moss and for trans-zeatin over cis-zeatin in the gymnosperm. The pH dependences of CK binding for these six CHKs showed a wide range, which may indicate different subcellular localization of these receptors at either the plasma- or endoplasmic reticulum membrane. Thus, the properties of the whole CK perception apparatuses in early-divergent lineages were demonstrated. Data show that during land plant evolution there was a diversification of the ligand specificity of various CHKs, in particular, the rise in preference for trans-zeatin over cis-zeatin, which indicates a steadily increasing specialization of receptors to various CKs. Finally, this distinct preference of individual receptors to different CK versions culminated in vascular plants, especially angiosperms.