Wheat streak mosaic virus Infects Systemically despite Extensive Coat Protein Deletions: Identification of Virion Assembly and Cell-to-Cell Movement Determinants

Viral coat proteins function in virion assembly and virus biology in a tightly coordinated manner with a role for virtually every amino acid. In this study, we demonstrated that the coat protein (CP) of Wheat streak mosaic virus (WSMV; genus Tritimovirus, family Potyviridae) is unusually tolerant of extensive deletions, with continued virion assembly and/or systemic infection found after extensive deletions are made. A series of deletion and point mutations was created in the CP cistron of wild-type and/or green fluorescent protein-tagged WSMV, and the effects of these mutations on cell-to-cell and systemic transport and virion assembly of WSMV were examined. Mutants with overlapping deletions comprising N-terminal amino acids 6 to 27, 36 to 84, 85 to 100, 48 to 100, and 36 to 100 or the C-terminal 14 or 17 amino acids systemically infected wheat with different efficiencies. However, mutation of conserved amino acids in the core domain, which may be involved in a salt bridge, abolished virion assembly and cell-to-cell movement. N-terminal amino acids 6 to 27 and 85 to 100 are required for efficient virion assembly and cell-to-cell movement, while the C-terminal 65 amino acids are dispensable for virion assembly but are required for cell-to-cell movement, suggesting that the C terminus of CP functions as a dedicated cell-to-cell movement determinant. In contrast, amino acids 36 to 84 are expendable, with their deletion causing no obvious effects on systemic infection or virion assembly. In total, 152 amino acids (amino acids 6 to 27 and 36 to 100 and the 65 amino acids at the C-terminal end) of 349 amino acids of CP are dispensable for systemic infection and/or virion assembly, which is rare for multifunctional viral CPs.     

New anticancer bastadin alkaloids from the sponge Dendrilla cactos

Two new bastadin alkaloids, bastadins-22 (1) and 23 (2), together with six known bastadins, bastadins-6 (3), -12 (4) (formerly basatadin-9), -14 (5), -15 (6), -16 (7), -19 (8), and a common steroid cholesterol were isolated from the sponge Dendrilla cactos. The structures of the isolates were established by the study of extensive spectroscopic analysis (1D and 2D NMR and MS data). Anticancer activity of the isolates has been carried out against Sup-T(1) cancer cells (T cell lymphoma).     

Amelioration in Growth and Phosphorus Assimilation of Poultry Birds Using Cell-Bound Phytase of Pichia Anomala

Summary Cell-bound phytase of Pichia anomala was produced in glucose–beef extract medium in shake flasks and in a laboratory fermenter at 25 °C for 24 h at 250 rev/min. In the fermenter the biomass production increased and the fermentation time was reduced from 24 to 16 h. Two-week-old broiler chicks were fed with the biomass-supplemented feed [at 100 g/7.5 kg; 50-phytase units/bird/day]. The overall weight gain in the biomass-fed chicks was higher (90.2%) than that of the control group (77.7%). The biomass incorporation in the feed of broiler chicks also resulted in a better phosphorus retention (29% in the control, and 73.68% in the biomass-fed) in the body, consequently an improved growth. There was a decrease in the excretion of phosphorus in the faeces of the chicks fed with phytase-supplemented diet (188.9 mg/g dry matter) as compared to the chicks fed on unsupplemented broiler finisher ration (509.4 mg/g dry matter). This eliminated the need to supplement phosphorus in their diet and also reduced phosphorus pollution. The feed conversion ratio was also lowered for chicks, which were biomass-fed as compared to the control.     

Development of Diagnostic Microscopic and Chemical Markers of Some Euphorbia Latexes

The latexes of the three Euphorbia species, namely E. antiquorum L., E. nerifolia L., and E. tirucalli L., are highly valued in the Indian system of medicine as purgatives, in addition to their specific and distinct therapeutic activities. In order to distinguish these latexes and develop their diagnostic microscopic and chemical markers, we performed extensive chemical and microscopic studies. The three latexes differ significantly in their microscopic features by exhibiting characteristic starch grain patterns. Although amoebic structures were found to be characteristic of E. antiquorum, dumb-bell and oval structures are characteristic of E. nerifolia and E. tirucalli, respectively. In addition, these latexes showed bone-shaped structures as a common feature, but these differed considerably in their length （10-60, 30-55, and 50-70 μm in length in E. antiquorum, E. nerifolia, and E. tirucalli, respectively）. The chemical markers nerifoliene and euphol were found to be common to both E. antiquorum and E. nerifolia, whereas euphol is the only marker for E. tirucalli. A reverse-phase high-performance thin-layer chromatographic （HPTLC） method was developed to distinguish these three latexes and to generate their standard fingerprinting patterns. Most significantly, the markers nerifoliene and euphol could be resolved by RP-18 F254s precoated aluminium plates and the latexes have been quantitatively estimated with respect to these markers. The developed microscopic, chemical and HPTLC patterns can be used to distinguish the three latexes.     

Xylose metabolism in a thermophilic mouldMalbranchea pulchella var.sulfurea TMD-8

The thermophilic mouldMalbranchea pulchella var.sulfurea TMD-8 produced extracellular xylanases in wheat straw hemicellulose as well as wheat straw. This mould utilized xylose less efficiently than glucose. Mycelial extracts contained xylose isomerase, xylose reductase, and xylitol dehydrogenase. Xylose isomerase was less thermostable than that from other microorganisms. However, xylitol dehydrogenase and xylose reductase were relatively more thermostable in comparison with these enzymes from other microorganisms. The affinity of xylose isomerase for xylose was very high (Km 10mM), while that of xylose reductase was low (Km 23.5mM). The xylitol dehydrogenase exhibited relatively high affinity for xylitol (Km 0.02mM). The activity of this enzyme, however, declined steeply, in the alkaline range. This is the first report on the occurrence of three intracellular enzymes, xylose isomerase, xylose reductase, and xylitol dehydrogenase in a thermophilic mould, which play an important role in xylose metabolism.     

Characteristics of thermostable endoxylanase and β-xylosidase of the extremely thermophilic bacterium Geobacillus thermodenitrificans TSAA1 and its applicability in generating xylooligosaccharides and xylose from agro-residues

An extremely thermophilic bacterial isolate that produces a high titer of thermostable endoxylanase and β-xylosidase extracellularly in an inducible manner was identified as Geobacillus thermodenitrificans TSAA1. The distinctive features of this strain are alkalitolerance and halotolerance. The endoxylanase is active over a broad range of pH (5.0–10.0) and temperatures (30–100 °C) with optima at pH 7.5 and 70 °C, while β-xylosidase is optimally active at pH 7.0 and 60 °C. The T _1/2 values of the endoxylanase and β-xylosidase are 30 min at 80 °C, and 180 min at 70 °C, respectively. The endoxylanase activity is stimulated by dithiothreitol, but inhibited strongly by EDAC and Woodward’s reagent K. N-BS and DEPC strongly inhibited β-xylosidase. MALDI-ToF (MS/MS) analysis of tryptic digest of β-xylosidase revealed similarity with that of G. thermodenitrificans NG 80-2, and suggested that this belongs to the GH 52 glycosyl hydrolase super family. The action of endoxylanase on birch wood xylan and agro-residues such as wheat bran and wheat straw liberated xylooligosaccharides similar to endoxylanases of the family 10 glycoside hydrolases, while the enzyme preparation having both endoxylanase and β-xylosidase liberated xylose as main hydrolysis product.     

In silico structural homology modeling of nif A protein of rhizobial strains in selective legume plants

Symbiosis is a complex genetic regulatory biological evolution which is highly specific pertaining to plant species and microbial strains. Biological nitrogen fixation in legumes is a functional combination of nodulation by nod genes and regulation by nif, fix genes. Three rhizobial strains (Rhizobium leguminosarum, Bradyrhizobium japonicum, and Mesorhizobium ciceri) that we considered for in silico analysis of nif A are proved to be the best isolates with respect to N₂ fixing for ground nut, chick pea and soya bean (in vitro) out of 47 forest soil samples. An attempt has been made to understand the structural characteristics and variations of nif genes that may reveal the factors influencing the nitrogen fixation. The primary, secondary and tertiary structure of nif A protein was analyzed by using multiple bioinformatics tools such as chou-Fasman, GOR, ExPasy ProtParam tools, Prosa -web. Literature shows that the homology modeling of nif A protein have not been explored yet which insisted the immediate development for better understanding of nif A structure and its influence on biological nitrogen fixation. In the present predicted 3D structure, the nif A protein was analyzed by three different software tools (Phyre2, Swiss model, Modeller) and validated accordingly which can be considered as an acceptable model. However further in silico studies are suggested to determine the specific factors responsible for nitrogen fixing in the present three rhizobial strains.     

Genetics of plantar interdigital ridge counts

The genetics of interdigital ridge counts of soles has been studied in a homogeneous Brahmin population of Andhra pradesh, India. The parameters considered are a-b, b-c and c-d ridge counts. A new measure - total plantar interdigital ridge counts (TPtIRC) - has been defined and an attempt has been made to evaluate the mode of inheritance of this trait. The results of the present study do not fully support the earlier conclusions regarding the genetics of a-b, b-c and c-d ridge counts.