Expression of sorghum gene <Emphasis Type="Italic">SbSGL</Emphasis> enhances grain length and weight in rice

Grain weight is a major determining factor of rice (Oryza sativa L.) yield and the comprehensive embodiment of grain length, width, and thickness. Here, we describe the molecular and functional characterization of SbSGL (Sorghum bicolor L. stress tolerance and grain length), a sorghum gene that encodes a putative member of the DUF1645 protein family of unknown function. Expression of SbSGL in rice promoted cell division and grain filling, which affected an array of traits of rice, including grain length, grain weight, and seed setting rate. Expression of SbSGL also affected the expression of genes related to the plant cell cycle and grain size.     

Global insight into the distribution of velvet-like B protein in <Emphasis Type="Italic">Cochliobolus</Emphasis> species and implication in pathogenicity and fungicide resistance

The Cochliobolus genus consist of over 55 species among which the 5 most devastating are Cochliobolus carbonum, Cochliobolus heterostrophus, Cochliobolus miyabeanus, Crocus sativus and Cochliobolus lunatus causing damages in sorghum, wheat, rice, maize, cassava and soybean estimated at over 10 billion USD per annum worldwide. The dynamic pathogenicity of Cochliobolus species and the plethora of infected hosts is determined by the evolution of virulence determinants such as the velvet-like B protein (VelB). Nonetheless, the knowledge on the distribution of Cochliobolus VelB and its implication in pathogenicity and fungicide resistance are often lacking. By scanning through the annotated genomes of C. lunatus, C. heterostrophus, C. carbonum, C. victoriae, C. sativus and C. miyabeanus, it is revealed that the numbers of ortholog VelB and cognates vary. By using the phylogenetic approach, it is established that the diversification rates among velvet-domain-containing proteins for phytopathogenic Cochliobolus species could impact differently on their oxidant and fungicide resistance potentials, ability to form appressoria-like structures and infection pegs during infection. This study provides new insights into the pathogenicity evolution of Cochliobolus species at the VelB locus which is relevant for designing effective strategies for durable management of Cochliobolus diseases.     

Biotechnological potential of a rhizosphere <Emphasis Type="Italic">Pseudomonas</Emphasis><Emphasis Type="Italic">aeruginosa</Emphasis> strain producing phenazine-1-carboxylic acid and phenazine-1-carboxamide

Bacterial phenazine metabolites belong to a group of nitrogen-containing heterocyclic compounds with antimicrobial activities. In this study, a rhizosphere Pseudomonas aeruginosa strain PA1201 was isolated and identified through 16S rDNA sequence analysis and fatty acid profiling. PA1201 inhibited the growth of various pathogenic microorganisms, including Rhizotonia solani, Magnaporthe grisea, Fusarium graminearum, Xanthomonas oryzae pv. oryzae, Xanthomonas oryzae pv. oryzicola, and Staphylococcus aureus. High Performance Liquid Chromatography showed that PA1201 produced high levels of phenazine-1-carboxylic acid (PCA), a registered green fungicide ‘Shenqinmycin’ with the fermentation titers of 81.7 mg/L in pigment producing medium (PPM) and 926.9 mg/L in SCG medium containing soybean meal, corn steep liquor and glucose. In addition, PA1201 produced another antifungal metabolite, phenazine-1-carboxaminde (PCN), a derivative of PCA, with the fermentation titers of 18.1 and 489.5 mg/L in PPM and SCG medium respectively. To the best of our knowledge, PA1201 is a rhizosphere originating P. aeruginosa strain that congenitally produces the highest levels of PCA and PCN among currently reported P. aeruginosa isolates, which endows it great biotechnological potential to be transformed to a biopesticide-producing engineering strain.     

The Peptide-Mediated Interactions Between Human Osteoclast-Stimulating Factor and Its Partner Proteins in Osteoporosis: Which Binds to Which?

Human osteoclast-stimulating factor (hOSF) is an intracellular protein produced by osteoclasts that induces osteoclast formation and bone resorption in osteoporosis by recruiting multiple signaling complexes with its diverse biological partners through peptide-mediated interactions (PMIs). The protein contains a modular peptide-recognition domain of Src homology 3 (SH3), which can recognize and bind to the polyproline regions of its partner proteins, as well as two N-terminal polyproline segments, which can be recognized and bound by the SH3 domains of its partner proteins. Here, we attempted to elucidate the complicated PMIs between the different SH3 domains and different polyprolines of hOSF and its three known interacting partners, i.e. proto-oncogene tyrosine-protein kinase (c-Src), survival motor neuron (SMN) and Src-associated in mitosis, 68 kD (Sam68). A total of 29 peptide segments containing the SH3-binding motif PXXP were extracted from these partner proteins, which are potential binding sites of hOSF SH3 domain, while the c-Src kinase also possesses a SH3 domain that may recognize and bind the two polyproline peptides at hOSF N-terminus. Structural bioinformatics analysis identified a number of biologically functional PMI candidates between these SH3 domains and these polyproline peptides, which were then tested in vitro using fluorescence spectroscopy assays. Consequently, it is found that (i) hOSF SH3 domain exhibits strong binding potency to two Sam68 peptides ³⁶RQPPLPHR⁴³ (K _d = 13.7 μM) and ⁴²⁵APPARPVK⁴³² (K _d = 3.2 μM) as well as moderate affinity to three SMN peptides ¹⁹³FLPPPPPM²⁰⁰ (K _d = 56.2 μM), ²³⁵PFPSGPPI²⁴² (K _d = 28.4 μM) and ²⁴⁶PPPICPDS²⁵³ (K _d = 74.5 μM), but has only weak or no binding to c-Src peptides. Instead, a proline-rich region at hOSF N-terminal that contains two overlapping peptides (³KPPPKPVK¹⁰ and ⁶PKPVKPGQ¹³) can be bound tightly by c-Src SH3 domain with high and moderate affinity (K _d = 5.8 and 39.6 μM, respectively).     

Elemental composition and flavonol content of <Emphasis Type="Italic">Pentaphylloides fruticosa</Emphasis> (L.) O. Schwarz in connection with plant age

The elemental composition and flavonol content of Pentaphylloides fruticosa (L.) O. Schwartz under the conditions of the Altai mountains are investigated. Some differences in the concentrations of elements and flavonols were detected in the leaves of P. fruticosa plants of different age classes corresponding to two periods of development: pregenerative (immature and virginal plants) and generative (young, middle-aged and old generative individuals). The maximum content of flavonols, in particular quercetin, in the leaves of P. fruticosa corresponds to the young generative age. A very high correlation between the flavonol content and the concentrations of Mn, Zn, Mo, and Se was revealed.     

Genome-wide identification and characterization of the RIO atypical kinase family in plants

Members of the right open reading frame (RIO) atypical kinase family are present in all three domains of life. In eukaryotes, three subfamilies have been identified: RIO1, RIO2, and RIO3. Studies have shown that the yeast and human RIO1 and RIO2 kinases are essential for the biogenesis of small ribosomal subunits. Thus far, RIO3 has been found only in multicellular eukaryotes. In this study, we systematically identified members of the RIO gene family in 37 species representing the major evolutionary lineages in Viridiplantae. A total of 84 RIO genes were identified; among them, 41 were classified as RIO1 and 43 as RIO2. However, no RIO3 gene was found in any of the species examined. Phylogenetic trees constructed for plant RIO1 and RIO2 proteins were generally congruent with the species phylogeny. Subcellular localization analyses showed that the plant RIO proteins were localized mainly in the nucleus and/or cytoplasm. Expression profile analysis of rice, maize, and Arabidopsis RIO genes in different tissues revealed similar expression patterns between RIO1 and RIO2 genes, and their expression levels were high in certain tissues. In addition, the expressions of plant RIO genes were regulated by two drugs: mycophenolic acid and actinomycin D. Function prediction using genome-wide coexpression analysis revealed that most plant RIO genes may be involved in ribosome biogenesis. Our results will be useful for the evolutionary analysis of the ancient RIO kinase family and provide a basis for further functional characterization of RIO genes in plants.     

Towards the mode of action of <Emphasis Type="Italic">Strobilanthes crispus</Emphasis> through integrated computational and experimental analyses

Bioactive sub-fractions from the tropical herbal plant Strobilanthes crispus (S. crispus) has been shown to induce apoptosis of breast cancer cells in vitro and reduce tumor size in vivo by our earlier studies. We have recently isolated five major compounds from S. crispus sub-fraction, namely lutein, β-sitosterol, campesterol, stigmasterol and pheophytin a. In this study, we set out to investigate each compound’s protein targets and mechanism of action through prediction of protein targets via a ligand-based target prediction protocol, Prediction IncluDinG INactives, and radioligand binding assays. The three phytosterol molecules (β-sitosterol, campesterol, stigmasterol) showed enrichment of hormone signaling GO terms [average ratio (AR) <0.01], while the SMAD signaling pathway was associated with pheophytin a (AR < 0.01). GO terms associated with retinoic acid receptor (RAR) and retinoid X receptor (RXR) were distinctly represented by protein targets of lutein (AR < 0.01). All members of the RAR/RXR family of proteins were predicted to be targeted by lutein, a feature that was not present in the other four S. crispus-derived compounds. Radioligand binding assay in vitro validated that lutein showed higher binding affinity with RXRα (IC₅₀: 5.74 µM; K_i: 4.55 µM) than RARα (IC₅₀: 25.1 µM; K_i: 14 µM). Molecular docking analysis demonstrated that lutein could occupy a large hydrophobic cavity of the hRXRα-LBP crystal structure mainly through hydrophobic interactions with leucine and isoleucine residues, and also hydrogen bond between a hydroxyl group of lutein with Glu²³⁹. Our findings suggest that lutein-RXRα interaction might play a role in the anti-breast cancer effects rendered by S. crispus.     

Nucleotide Correspondence between Protein-Coding Sequences of <Emphasis Type="Italic">Helicobacter pylori</Emphasis> Strains 26695 and J99

Comparison of ORFs between H. pylori strains 26695 and J99 showed that transitions (more than 3%) prevail over transversions (less than 1%). The predominance of transitions was explained by the high rates of cytosine replacement by thymine in the coding (3.5–5.3%) and noncoding (2.9–3.9%) DNA strands. The proportion of transversion-type correspondences (A → C, A → T, C → A, C → G, G → C, G → T, T → A, and T → G) did not exceed 0.84%. The highest proportion (28.3%) was observed for correspondences between C and T in ACGT-ATGT, the target site of active methyltransferase of H. pylori J99 (M.Hpy99XI). It was assumed that C → T mutations due to cytosine methylation-deamination are prevalent in H. pylori.     

Pathogenicity of<Emphasis Type="Underline">Fusarium</Emphasis><Emphasis Type="Underline">SPP</Emphasis>. contributing to the stalk rot of Maize in Poland

During 1985–1989 a stalk rot of early maturity hybrids of maize was studied in Radzikow (Central Poland). It was found thatFusarium species were dominant on plants with stalk rot symptoms. Spectrum ofFusarium spp. had changed within the years. The most frequently isolated were:F.subglutinans,F.culmorum andF.crookwellense. When the disease developed early in the seasonF.graminearum was also present.Predominant species were examined for their pathogenicity according to the modified method of Molot, Simone (1967). Isolates ofF.graminearum andF.culmorum were found to be strong pathogens,F.crookwellense andF.subglutinans — moderate andF.oxysporum andF.eguiseti were the weak ones     

Karyo-taxonomic study of the genus<Emphasis Type="Italic">Pseudolysimachion</Emphasis> (<Emphasis Type="Italic">Scrophulariaceae</Emphasis>) in the Czech Republic and Slovakia

Flow cytometry was used to determine ploidy levels in the Czech and Slovak taxa of the genusPseudolysimachion (W.D.J. Koch)Opiz (=Veronica auct. p.p.,Scrophulariaceae). In total, 123 populations from the Czech Republic, Slovakia, Ukraine (one locality), Austria (one locality) and Hungary (one locality) were analyzed. InP. maritimum (L.)Á. Löve etD. Löve andP. spicatum (L.)Opiz, two cytotypes were found: diploid (2n=2x=34) and tetraploid (2n=4x=68). In both species the tetraploid cytotype predominated (P. maritimum: 41 tetraploid populations out of 45;P. spicatum: 57 tetraploid populations out of 58). The two cytotypes ofP. maritimum have no taxonomic significance because ploidy level is not obviously correlated with morphology, distribution pattern or ecology. Tetraploid populations ofP. spicatum belong to two morphologically different subspecies, subsp.spicatum and subsp.fischeri Trávní?ek. The diploid cytotype (one population only) should be provisionally classified as a third subspecies ofP. spicatum, which is morphologically similar to the Asian subsp.porphyrianum (Pavlov)Trávní?ek. Only diploid plants (2n=2x=34) ofP. orchideum (Crantz)Wraber were found; all 13 populations that were analyzed belong toP. orchideum s.str. One diploid population sample ofP. spurium subsp.foliosum (Waldst. etKit.)Holub (2n=2x=34) and one tetraploid sample ofP. incanum subsp.pallens (Host)Trávní?ek (2n=4x=68) were also analyzed. In addition, three tetraploid populations of hybrid origin were investigated:P. maritimum ×P. spicatum subsp.spicatum (one population) andP. maritimum ×P. spurium subsp.foliosum (two populations). While hybrid plants ofP. maritimum ×P. spicatum arose from tetraploid parental species, plants ofP. maritimum ×P. spurium probably resulted from a cross between tetraploidP. maritimum and diploidP. spurium. The putative origin and evolutionary importance of polyploids in thePseudolysimachion are discussed.     

Studies in the taxonomy of the Polypores II

The following genera are redefined:Albatrellus S. F. Gray,Heterobasidion Bref.,Haploporus Bond. et Sing. ex Sing.,Fomitopsis P. Karst. andRigidoporus Murrill two new subgenera are described:Polyporus subgen.Dendropolyporus Pouz. (type:Polyporus umbellatus) andRigidoporus subgen.Neooxyporus Pouz. (type:Polyporus latemarginatus); the genusOxyporus (Bourd. etGalz.)Donk is classified as a subgenus of the genusRigidoporus,Murrill and the generaBjerkandera P. Karst. andLeptoporus quél. are classified as subgenera of the genusTyromyces P. Karst. The new subfamilyAlbatrelloideae Pouz. (genera:Albatrellus andGrifola) is described and 14 new specific combinations are made. The new genusIrpicodon Pouz. (type:Irpex pendulus) is proposed.     

Functional expression of a human GDP-<Emphasis Type="SmallCaps">l</Emphasis>-fucose transporter in <Emphasis Type="Italic">Escherichia coli</Emphasis>

Objectives

To investigate the translocation of nucleotide-activated sugars from the cytosol across a membrane into the endoplasmatic reticulum or the Golgi apparatus which is an important step in the synthesis of glycoproteins and glycolipids in eukaryotes.

Results

The heterologous expression of the recombinant and codon-adapted human GDP-l-fucose antiporter gene SLC35C1 (encoding an N-terminal OmpA-signal sequence) led to a functional transporter protein located in the cytoplasmic membrane of Escherichia coli. The in vitro transport was investigated using inverted membrane vesicles. SLC35C1 is an antiporter specific for GDP-l-fucose and depending on the concomitant reverse transport of GMP. The recombinant transporter FucT1 exhibited an activity for the transport of ³H-GDP-l-fucose with a V_max of 8 pmol/min mg with a K_m of 4 µM. The functional expression of SLC35C1 in GDP-l-fucose overproducing E. coli led to the export of GDP-l-fucose to the culture supernatant.

Conclusions

The export of GDP-l-fucose by E. coli provides the opportunity for the engineering of a periplasmatic fucosylation reaction in recombinant bacterial cells.

     

Infection ability of mycelium and spores of<Emphasis Type="Underline">Microdochium</Emphasis><Emphasis Type="Underline">nivale</Emphasis> (Fr) samuels hallett to<Emphasis Type="Underline">Lolium</Emphasis><Emphasis Type="Underline">Perenne</Emphasis> L.

Mycelium and spores ofMicrodochium nivale /Syn.Fusarium nivale/ were compared according to their ability to infect plants ofLolium perenne. The experiments were carried out according to the “cold chamber” method (Cormack, Lebeau 1956 modified by Pronczuk 1987). Between these two types of inoculum significant differences were found. The spore inoculum did not give any symptoms while the mycelial inoculum incited a severe disease in plants ofLolium perenne during one month of incubation.Under laboratory conditions it was found that the spore cultures ofMicrodochium nivale grew very slowly at 0 – 1°C, whereas their growth at 18 – 20°C was very fast. Growth of the mycelial cultures was not as profoundly affected by temperatures studied as the spore ones.It was concluded that to incite a disease the spore inoculum require longer incubation time than mycelial ones. The mycelial inoculum is more useful for screening of plants for resistsance.     

First record of <Emphasis Type="Italic">Pojetaia runnegari</Emphasis> Jell, 1980 and <Emphasis Type="Italic">Fordilla</Emphasis> Barrande, 1881 from the Middle East (Taurus Mountains,Turkey) and critical review of Cambrian bivalves

Cambrian bivalves from the Middle East are reported here for the first time. They come from early “Middle Cambrian” and latest “Early Cambrian” limestones of the lower Çal Tepe Formation at the type locality (near Seydi?ehir, western Taurides). The majority of the new findings consists of Pojetaia runnegari Jell, 1980, but a few specimens of Fordilla sp. represent the first report of this genus from “Middle Cambrian” strata. Based on a compilation of the hitherto reported, but mostly revised Cambrian bivalves, the today widely accepted taxa are discussed. The genera Pojetaia Jell, 1980 and Fordilla Barrande, 1881 are critically evaluated, and three valid species are included in Pojetaia: P. runnegari Jell, 1980, P. sarhroensis Geyer and Streng, 1998, and—with limitations—P. ostseensis Hinz-Schallreuter, 1995. Fordilla also includes three species: F. troyensis Barrande, 1881, F. sibirica Krasilova, 1977, and F. germanica Elicki, 1994. The Cambrian genera Tuarangia MacKinnon, 1982, Camya Hinz-Schallreuter, 1995, and Arhouriella Geyer and Streng, 1998 most probably belong to the class Bivalvia. Palaeoecologically, the Cambrian bivalves of the Western Perigondwanan shelf seem to occur in a relatively small window of low-energy, subtidal, open-marine, warm-water conditions on a muddy carbonate ramp or platform with reduced sedimentation rate. The frequently interpreted infaunal mode of life of Pojetaia and Fordilla is questioned by observations of similarly organized modern bivalves. The palaeogeographical distribution of Pojetaia and Fordilla is discussed with respect to their early ontogeny and to differences in the recent state of knowledge on shelly fossils from Cambrian carbonate successions of Perigondwana.     

Characterization of aspartate kinase and homoserine dehydrogenase from <Emphasis Type="Italic">Corynebacterium glutamicum</Emphasis> IWJ001 and systematic investigation of <Emphasis Type="SmallCaps">l</Emphasis>-isoleucine biosynthesis

Previously we have characterized a threonine dehydratase mutant TD^F383V (encoded by ilvA1) and an acetohydroxy acid synthase mutant AHAS^{P176S, D426E, L575W} (encoded by ilvBN1) in Corynebacterium glutamicum IWJ001, one of the best l-isoleucine producing strains. Here, we further characterized an aspartate kinase mutant AK^A279T (encoded by lysC1) and a homoserine dehydrogenase mutant HD^G378S (encoded by hom1) in IWJ001, and analyzed the consequences of all these mutant enzymes on amino acids production in the wild type background. In vitro enzyme tests confirmed that AK^A279T is completely resistant to feed-back inhibition by l-threonine and l-lysine, and that HD^G378S is partially resistant to l-threonine with the half maximal inhibitory concentration between 12 and 14 mM. In C. glutamicum ATCC13869, expressing lysC1 alone led to exclusive l-lysine accumulation, co-expressing hom1 and thrB1 with lysC1 shifted partial carbon flux from l-lysine (decreased by 50.1 %) to l-threonine (4.85 g/L) with minor l-isoleucine and no l-homoserine accumulation, further co-expressing ilvA1 completely depleted l-threonine and strongly shifted carbon flux from l-lysine (decreased by 83.0 %) to l-isoleucine (3.53 g/L). The results demonstrated the strongly feed-back resistant TD^F383V might be the main driving force for l-isoleucine over-synthesis in this case, and the partially feed-back resistant HD^G378S might prevent the accumulation of toxic intermediates. Information exploited from such mutation-bred production strain would be useful for metabolic engineering.     

Contamination of freshly harvested maize kernels with<Emphasis Type="Underline">Fusarium</Emphasis> mycotoxins on Bihar state,India

Freshly harvested maize samples, collected from different fields of Bhagalpur during January-March, 1989, were analysed for the presence of Fusarium species and their toxins.F. moniliforme was most common followed byF. roseum,F. sporotrichioides,F. graminearum andF. equiseti. Different strains of these species produced zearalenone (11.2–28.2 μ/g), DON (0.3–2.9 μg/g) and T-2 (5.2–20.6 μg/g) toxins on mostrice medium. Fifteen per cent, out of 86 maize samples analysed, were found to be contaminated with various levels of above toxins, which occurred either alone or in groups. Toxin concentration in contaminated samples varied from 0.76–1.5 μg/g (ZEN), 0.41–202 μg/g (DON) and 0.55–2.92 μg/g (T-2).     

Flechtensystematische Studien IV. Die GattungGyalidea Lett

Im Artikel wird die ursprüngliche Gattungsdiagnose derGyalidea Lett. um die Merkmale der Pilzkomponente ergänzt. Die angenommenen verwandtschaftlichen Beziehungen derGyalidea zu der FamilieAsterothyriaceae werden diskutiert. Alle bisher festgestellten Arten mit Übersichten der revidierten Proben werden kurz beschrieben. Neue Taxa und Kombinationen:Gyalidea dodgei spec. n.,G. epiphylla spec. n.,G. mayaguezensis spec. n.,G. portoricensis spec. n.,G. fritzei (Stein) comb. n.,G. fritzei var.rivularis (Eitn.) comb. n.,G. hyalinescens (Nyl.) comb. n.,G. lecideopsis var.convarians (Nyl.) comb. n.,G. lecideopsis var.stigmatoides (Nyl.) comb. n.,G. mexicana (B. de Lesd.) comb. n. undG. subscutellaris (Vězda) comb. n.